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Direct formate fuel cells (DFFCs) as promising energy technologies have been applied for portable and wearable devices. However, for the formate oxidation reaction (FOR), the deficiency of catalysts has prevented DFFCs from practical applications. Herein, we prepared a Pd-loaded CeO

Both LRF (

We develop a new factor selection methodology of spanning the space of hedge fund risk factors with all available exchange traded funds (ETFs). We demonstrate the efficacy of the methodology with out‐of‐sample individual hedge fund return replication by ETF clone portfolios. This is consistent with our interpretation of ETF returns as proxies to risk factors driving hedge fund returns. We further consider portfolios of “cloneable” and “noncloneable” hedge funds, defined as top and bottom in‐sample R2 matches, and demonstrate that our ETF clone portfolios slightly outperform cloneable hedge funds out of sample.

Two species of dictyostelids (Dictyostelium aureocephalum and Heterostelium filamentosum) new to China were isolated from samples of forest soils; and a second Chinese record of Coremiostelium polycephalum (previously recorded from Taiwan) was also isolated. Descriptions and illustrations based on these isolates are provided.

An NHC-catalyzed α-carbon amination of chloroaldehydes was developed. Cyclohexadiene-1,2-diimines are used as amination reagents and four-atom synthons. Our reaction affords optically enriched dihydroquinoxalines that are core structures in natural products and synthetic bioactive molecules. NRF (Natl Research Foundation, S’pore) ASTAR (Agency for Sci., Tech. and Research, S’pore) MOE (Min. of Education, S’pore) Accepted version

In this study, MoSi2/SiC coating with high infrared emissivity was fabricated by atmospheric plasma spray (APS) method, in view of the potential application in high temperature energy-saving area. The phase composition, microstructure, infrared emissivity and thermal shock resistance of the obtained coating were characterized. Compared with MoSi2 coating, the MoSi2/SiC coating exhibited a higher emissivity of 0.908 at 1400 °C, owing to the smaller band gap energy and the distortion of Mo4.8Si3C0.6. Moreover, high thermal shock resistance was validated, as no emissivity degradation or obvious spalling of coating was found and only a few microcracks could be observed in the surface after 50 thermal cycles with water-quenching from 1300 °C to 25 °C.

Summary Recent studies suggest that mitochondria can be transferred between cells to support the survival of metabolically compromised cells. However, whether intercellular mitochondria transfer occurs in white adipose tissue (WAT) or regulates metabolic homeostasis in vivo remains unknown. We found that macrophages acquire mitochondria from neighboring adipocytes in vivo and that this process defines a transcriptionally distinct macrophage subpopulation. A genome-wide CRISPR-Cas9 knockout screen revealed that mitochondria uptake depends on heparan sulfates (HS). High-fat diet (HFD)-induced obese mice exhibit lower HS levels on WAT macrophages and decreased intercellular mitochondria transfer from adipocytes to macrophages. Deletion of the HS biosynthetic gene Ext1 in myeloid cells decreases mitochondria uptake by WAT macrophages, increases WAT mass, lowers energy expenditure, and exacerbates HFD-induced obesity in vivo. Collectively, this study suggests that adipocytes and macrophages employ intercellular mitochondria transfer as a mechanism of immunometabolic crosstalk that regulates metabolic homeostasis and is impaired in obesity.

In order to improve the performance and speed of data storage, this paper designs a data mining system based on cloud computing. The basic structure, operation mode and programming principle of the cloud computing platform Spark are described in detail. The cloud computing platform Spark realizes the parallel design of decision tree C4.5 algorithm and K-medoids clustering algorithm, which greatly improves the operation speed, convergence speed and result stability of the algorithm. The experimental results show that the data mining system designed in this paper has faster operation speed and better classification efficiency when analyzing and processing massive data.

Summary The mevalonate pathway is essential for the synthesis of isoprenoids and cholesterol. Adipose tissue is known as a major site for cholesterol storage; however, the role of the local mevalonate pathway and its synthesized isoprenoids remains unclear. In this study, adipose-specific mevalonate pathway-disrupted (aKO) mice were generated through knockout of 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase (HMGCR). aKO mice showed serious lipodystrophy accompanied with glucose and lipid metabolic disorders and hepatomegaly. These metabolic variations in aKO mice were dramatically reversed after fat transplantation. In addition, HMGCR-disrupted adipocytes exhibited loss of lipid accumulation and an increase of cell death, which were ameliorated by the supplementation of mevalonate and geranylgeranyl pyrophosphate but not farnesyl pyrophosphate and squalene. Finally, we found that apoptosis may be involved in adipocyte death induced by HMGCR down-regulation. Our findings indicate that the mevalonate pathway is essential for adipocytes and further suggest that this pathway is an important regulator of adipocyte turnover., Graphical Abstract, Highlights • HMGCR deficiency in adipocytes causes lipodystrophy • HMGCR deficiency in adipocytes triggers several metabolic disorders • Cholesterol and pioglitazone cannot improve HMGCR-deficiency-induced lipodystrophy • GGPP is critical for adipocyte survival by regulating apoptosis, Pathophysiology; Molecular Mechanism of Behavior; Diabetology; Specialized Functions of Cells

The multilayered CoO-CoAl2O4 solar selective films were prepared on Co-WC coatings with different mole ratio of Co and Al by sol-gel process. The thin film has high and low refractive indices, respectively. The inner layer can improve surface condition of Co-WC coating as a high absorbing film and buffer lay, annealed at 650 °C in vacuum. The outer layer was annealed at the same condition. The absorptance ( α ) of the multilayer structure coating increased from 0.873 to 0.932. The properties of the sols were characterized by thermogravimetry-differential scanning calorimetry (TG-DSC). The phase compositions and structure of samples annealed at 650 °C were analyzed by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The microstructure and elements distribution of thin films were investigated by field emission scanning electron microscopy (FE-SEM) and energy dispersive spectrometer (EDS), respectively. The absorptance of coatings indirectly indicate the binding force between the Co-WC substrate, durability, long-time stability and corrosion resistance are fine. The results illustrated that defects on surface of the Co-WC coating gradually decrease with the deposition of sol films. And the good element gradients in multilayer structures and the structure of thin films might be the reasons for its improvement in absorptance.

Based on the outstanding high-temperature stability of WC-Co coating prepared by high-velocity oxy-fuel (HVOF) spraying, CuCoMnOx, CuCoMnOx-SiO2, and SiO2 sols synthesized by sol-gel method were deposited successively on the coating after grinding the surface of it. CuCoMnOx was used as sealing layer to fill the larger pores and grooves on the surface, then, the composition CuCoMnOx-SiO2 sol was deposited as the second sealing layer to eliminate the remaining smaller pores as well as transition layer to connect the sealing layer and the uppermost SiO2 anti-reflective layer. The absorptance (α) of the new multilayer structure coating obtained through this way increased from 0.821 to 0.915 and the emittance (e) decreased from 0.434 to 0.290. After being annealed for 50 h at 550 °C under non-vacuum environment, the α and e of the multilayered coatings stack changed to 0.901/0.320. The structural transformation of the coatings and mechanisms of its improvement were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and laser scanning confocal microscope (LSCM). The results indicated that with the deposition of sol films in turn, defects on the surface of WC-Co coating were gradually reduced and formed a compact surface eventually, in correspondence, roughness of it reduced. And the formation of good element gradients in multilayer structures might be the explanation for its substantial improvement in optical performance.

High infrared emissivity coating possesses great value in practical application, whether in the military or civilian areas. In this study, B-NiCr precursor powder containing NiO, Cr2O3 and ZrB2 was calcined at 1300 °C and then used to prepare a high infrared emissivity B-NiCr coating via atmospheric plasma spraying. A large number of test methods were employed to analyze the powder and coating, including TG-DSC, XRD, FE-SEM, infrared spectrometer and so on. The result of infrared emissivity measurement indicates that the coating possesses maximum infrared emissivity of 0.908 at 1000 °C while the infrared emissivity is 0.901 after thermal shock test. Comparing with NiCr coating, Ni2CrO2(BO3) formed during calcination may be the main factor to improve the infrared emissivity of B-NiCr coating. The B-NiCr coating possesses good thermal shock resistance and can withstand 50 times thermal shock at least without falling off, from 800 °C to room temperature.

We examine how natural disasters affect the corporate environmental, social, and governance (ESG) disclosure policies of firms located close to disaster areas. We study firms located in counties neighboring those affected by natural disasters and find that, on average, these firms increase their ESG disclosure transparency over the period subsequent to the disaster. Given that our sample firms are located outside of the area directly affected by the disaster, the changes in disclosure transparency after the disaster are consistent with managers increasing their preference for transparency as their risk salience increases. Further, we find that, though the disaster may be environmental by nature, nearby firms increase their social and governance disclosures in addition to their environmental disclosures. To investigate whether or not the increased transparency is a rational response to the disaster, we explore the costs of capital for the firms in our sample to study what impacts, if any, the increased transparency engenders for the firm. We find that increases in ESG disclosure are associated with reductions in the cost of debt after the disaster consistent with the notion that markets find the increased transparency to be value relevant.

Peroxisome proliferator-activated receptor α (PPARα) is important in the regulation of lipid metabolism and expressed at high levels in the liver. Although PPARα is also expressed in adipose tissue, little is known about the relationship between its activation and the regulation of glucose metabolism. In this study, we developed adipose tissue specific PPARα over-expression (OE) mice. Metabolomics and insulin tolerance tests showed that OE induces branched-chain amino acid (BCAA) profile and improvement of insulin sensitivity. Furthermore, LC-MS and PCR analyses revealed that OE changes free fatty acid (FFA) profile and reduces obesity-induced inflammation. These findings suggested that PPARα activation in adipose tissue contributes to the improvement of glucose metabolism disorders via the enhancement of BCAA and FFA metabolism.

Among dietary fatty acids with immunologic effects, ω-3 polyunsaturated fatty acids, such as α-linolenic acid (ALA), have been considered as factors that contribute to the differentiation of M2-type macrophages (M2 macrophages). In this study, we examined the effect of ALA and its gut lactic acid bacteria metabolites 13-hydroxy-9(Z),15(Z)-octadecadienoic acid (13-OH) and 13-oxo-9(Z),15(Z)-octadecadienoic acid (13-oxo) on the differentiation of M2 macrophages from bone marrow-derived cells (BMDCs) and investigated the underlying mechanisms. BMDCs were stimulated with ALA, 13-OH, or 13-oxo in the presence of IL-4 or IL-13 for 24 h, and significant increases in M2 macrophage markers CD206 and Arginase-1 (Arg1) were observed. In addition, M2 macrophage phenotypes were less prevalent following cotreatment with GPCR40 antagonists or inhibitors of PLC-β and MEK under these conditions, suggesting that GPCR40 signaling is involved in the regulation of M2 macrophage differentiation. In further experiments, remarkable M2 macrophage accumulation was observed in the lamina propria of the small intestine of C57BL/6 mice after intragastric treatments with ALA, 13-OH, or 13-oxo at 1 g/kg of body weight per day for 3 d. These findings suggest a novel mechanism of M2 macrophage differentiation involving fatty acids from gut lactic acid bacteria and GPCR40 signaling.-Ohue-Kitano, R., Yasuoka, Y., Goto, T., Kitamura, N., Park, S.-B., Kishino, S., Kimura, I., Kasubuchi, M., Takahashi, H., Li, Y., Yeh, Y.-S., Jheng, H.-F., Iwase, M., Tanaka, M., Masuda, S., Inoue, T., Yamakage, H., Kusakabe, T., Tani, F., Shimatsu, A., Takahashi, N., Ogawa, J., Satoh-Asahara, N., Kawada, T. α-Linolenic acid-derived metabolites from gut lactic acid bacteria induce differentiation of anti-inflammatory M2 macrophages through G protein-coupled receptor 40.

Gut microbiota can regulate the host energy metabolism; however, the underlying mechanisms that could involve gut microbiota-derived compounds remain to be understood. Therefore, in this study, we investigated the effects of KetoA [10-oxo-12(Z)-octadecenoic acid]-a linoleic acid metabolite produced by gut lactic acid bacteria-on whole-body energy metabolism and found that dietary intake of KetoA could enhance energy expenditure in mice, thereby protecting mice from diet-induced obesity. By using Ca2+ imaging and whole-cell patch-clamp methods, KetoA was noted to potently activate transient receptor potential vanilloid 1 (TRPV1) and enhance noradrenalin turnover in adipose tissues. In addition, KetoA up-regulated genes that are related to brown adipocyte functions, including uncoupling protein 1 (UCP1) in white adipose tissue (WAT), which was later diminished in the presence of a β-adrenoreceptor blocker. By using obese and diabetic model KK-Ay mice, we further show that KetoA intake ameliorated obesity-associated metabolic disorders. In the absence of any observed KetoA-induced antiobesity effect or UCP1 up-regulation in TRPV1-deficient mice, we prove that the antiobesity effect of KetoA was caused by TRPV1 activation-mediated browning in WAT. KetoA produced in the gut could therefore be involved in the regulation of host energy metabolism.-Kim, M., Furuzono, T., Yamakuni, K., Li, Y., Kim, Y.-I., Takahashi, H., Ohue-Kitano, R., Jheng, H.-F., Takahashi, N., Kano, Y., Yu, R., Kishino, S., Ogawa, J., Uchida, K., Yamazaki, J., Tominaga, M., Kawada, T., Goto, T. 10-oxo-12(Z)-octadecenoic acid, a linoleic acid metabolite produced by gut lactic acid bacteria, enhances energy metabolism by activation of TRPV1.

Obesity causes excess fat accumulation in white adipose tissues (WAT) and also in other insulin-responsive organs such as the skeletal muscle, increasing the risk for insulin resistance, which can lead to obesity-related metabolic disorders. Peroxisome proliferator-activated receptor-α (PPARα) is a master regulator of fatty acid oxidation whose activator is known to improve hyperlipidemia. However, the molecular mechanisms underlying PPARα activator-mediated reduction in adiposity and improvement of metabolic disorders are largely unknown. In this study we investigated the effects of PPARα agonist (fenofibrate) on glucose metabolism dysfunction in obese mice. Fenofibrate treatment reduced adiposity and attenuated obesity-induced dysfunctions of glucose metabolism in obese mice fed a high-fat diet. However, fenofibrate treatment did not improve glucose metabolism in lipodystrophic A-Zip/F1 mice, suggesting that adipose tissue is important for the fenofibrate-mediated amelioration of glucose metabolism, although skeletal muscle actions could not be completely excluded. Moreover, we investigated the role of the hepatokine fibroblast growth factor 21 (FGF21), which regulates energy metabolism in adipose tissue. In WAT of WT mice, but not of FGF21-deficient mice, fenofibrate enhanced the expression of genes related to brown adipocyte functions, such as Ucp1, Pgc1a, and Cpt1b. Fenofibrate increased energy expenditure and attenuated obesity, whole body insulin resistance, and adipocyte dysfunctions in WAT in high-fat-diet-fed WT mice but not in FGF21-deficient mice. These findings indicate that FGF21 is crucial for the fenofibrate-mediated improvement of whole body glucose metabolism in obese mice via the amelioration of WAT dysfunctions.

Obesity predisposes to cancer and a virtual universality of nonalcoholic fatty liver disease (NAFLD). However, the impact of hepatic steatosis on liver metastasis is enigmatic. We find that while control mice were relatively resistant to hepatic metastasis, those which were lipodystrophic or obese, with NAFLD, had a dramatic increase in breast cancer and melanoma liver metastases. NAFLD promotes liver metastasis by reciprocal activation initiated by tumor-induced triglyceride lipolysis in juxtaposed hepatocytes. The lipolytic products are transferred to cancer cells via fatty acid transporter protein 1, where they are metabolized by mitochondrial oxidation to promote tumor growth. The histology of human liver metastasis indicated the same occurs in humans. Furthermore, comparison of isolates of normal and fatty liver established that steatotic lipids had enhanced tumor-stimulating capacity. Normalization of glucose metabolism by metformin did not reduce steatosis-induced metastasis, establishing the process is not mediated by the metabolic syndrome. Alternatively, eradication of NAFLD in lipodystrophic mice by adipose tissue transplantation reduced breast cancer metastasis to that of control mice, indicating the steatosis-induced predisposition is reversible., Nonalcoholic fatty liver disease promotes liver metastasis in mice, likely due to lipid transfer to tumor cells.

We previously established that global deletion of the enhancer of trithorax and polycomb (ETP) gene, Asxl2, prevents weight gain. Because proinflammatory macrophages recruited to adipose tissue are central to the metabolic complications of obesity, we explored the role of ASXL2 in myeloid lineage cells. Unexpectedly, mice without Asxl2 only in myeloid cells (Asxl2(ΔLysM)) were completely resistant to diet-induced weight gain and metabolically normal despite increased food intake, comparable activity, and equivalent fecal fat. Asxl2(ΔLysM) mice resisted HFD-induced adipose tissue macrophage infiltration and inflammatory cytokine gene expression. Energy expenditure and brown adipose tissue metabolism in Asxl2(ΔLysM) mice were protected from the suppressive effects of HFD, a phenomenon associated with relatively increased catecholamines likely due to their suppressed degradation by macrophages. White adipose tissue of HFD-fed Asxl2(ΔLysM) mice also exhibited none of the pathological remodeling extant in their control counterparts. Suppression of macrophage Asxl2 expression, via nanoparticle-based siRNA delivery, prevented HFD-induced obesity. Thus, ASXL2 controlled the response of macrophages to dietary factors to regulate metabolic homeostasis, suggesting modulation of the cells’ inflammatory phenotype may impact obesity and its complications.

We explore the effect of home price appreciation on residential lending standards in the U.S. across different sample periods. Using housing supply elasticity measures as instrumental variables for home price changes, we find that rising home prices led to easing lending standards between 2001 and 2006. Mortgage acceptance rates increased more in MSAs that experienced higher home price appreciation, contributing to the credit boom. However, we find that home price appreciation is associated with tighter lending standards between 2012 and 2016, suggesting that banks took a more cautious view of home price appreciation after the financial crisis. To study the negative relationship between home price appreciation and lending standards during the post-crisis years, we examine loan acceptance rates of small and large banks separately. We find that it was the small banks who lowered loan acceptance rates in MSAs with higher home price appreciation, which caused the overall loan acceptance rates to decline.

Objective Obesity-induced inflammation plays a pivotal role in the pathogenesis of insulin resistance and type 2 diabetes. Xanthoangelol (XA) and 4-hydroxyderrcin (4-HD), phytochemicals extracted from Angelica keiskei, have been reported to possess various biological properties. Whether XA and 4-HD alleviate obesity-induced inflammation and inflammation-induced adipocyte dysfunction was investigated. Methods For the in vitro study, a co-culture system composed of macrophages and adipocytes and macrophages stimulated with conditioned medium derived from fully differentiated adipocytes was conducted. For the in vivo study, mice were fed a high-fat diet supplemented with XA for 14 weeks. Results XA and 4-HD suppressed inflammatory factors in co-culture system. Moreover, treatment of RAW macrophages with XA and 4-HD moderated the suppression of uncoupling protein 1 promoter activity and gene expression in C3H10T1/2 adipocytes, which was induced by conditioned medium derived from LPS-stimulated RAW macrophages. Also, XA and 4-HD inhibited c-Jun N-terminal kinase phosphorylation, nuclear factor-κB, and activator protein 1, the last two being transcription activators in activated macrophages. Furthermore, in mice fed the high-fat diet, XA reduced inflammatory factors within the white adipose tissue. Conclusions These results suggest that XA and 4-HD might be promising phytochemicals to suppress obesity-induced inflammation and inflammation-induced adipocyte dysfunction.

The diyne complex [Cp*Ir(CO)(η2-ArC≡CC≡CAr)] reacts with two-electron donor ligands to form the iridacyclobutenone [Cp*Ir(L){C(C≡CAr)=C(Ar)C=O}]. Kinetic measurements and computational studies support the proposal that the reaction pathway involves alkyne insertion followed by coordination of the two-electron donor ligand.

The bis(alkynyl) iridium complexes [Cp*Ir(L)(C CAr) 2 ] undergo an Arbuzov-type reaction with phosphites to give four-membered iridacyclic phosphonates [Cp*Ir(L){C(Ar) C[P( O)(OR) 2 ]C CHAr}]. These can isomerise to a five-membered iridafuran in the presence of a strong acid. In the absence of a phosphite, the bis(alkynyl) iridium complexes undergo acid-catalysed aerobic oxidation to form 1,2-diketone iridabenzofurans [Cp*Ir(L){C 6 H 4 - 1,2 -CH CC( O)C( O)Ar}]. A common reaction pathway involving initial protonation and alkynyl migration is proposed.

The design of a 13.56 MHz/402 MHz autonomous wireless sensor node with asynchronous ECG monitoring for near field communication is presented. The sensor node consists of an RF energy harvester (RFEH), a power management unit, an ECG readout, a data encoder and an RF backscattering transmitter. The energy harvester supplies the system with 1.25 V and offers a power conversion efficiency of 19% from a ${-}13$ dBm RF source at 13.56 MHz. The power management unit regulates the output voltage of the RFEH to supply the ECG readout with ${\rm V}_{\rm ECG} = 0.95$ V and the data encoder with ${\rm V}_{\rm DE} = 0.65$ V . The ECG readout comprises an analog front-end (low noise amplifier and programmable voltage to current converter) and an asynchronous level crossing ADC with 8 bits resolution. The ADC output is encoded by a pulse generator that drives a backscattering transmitter at 402 MHz. The total power consumption of the sensor node circuitry is 9.7 $\mu$ W for a data rate of 90 kb/s and a heart rate of 70 bpm. The chip has been designed in a 0.18 $\mu$ m CMOS process and shows superior RF input power sensitivity and lower power consumption when compared to previous works.

The alkynyl ligands in the iridium(III) complex [Cp*Ir(CO)(C CPh) 2 ] undergo reductive coupling to form the diyne complex [Cp*Ir(CO)(PhC CC CPh)]. This process is assisted by nucleophilic attack at the carbonyl ligand by the solvent.

A novel and economical one-step liquid phase route combining the liquid phase reaction with rotary evaporation is successfully adopted to prepare LiFePO4@C composite materials using iron phosphate dihydrate as iron source and phosphorus source. High temperature sintering was used to complete carbonization and control the size of precursor particles. X-ray diffraction (XRD) shows that all diffraction peaks are consistent of the standard pattern of FePO4 2H2O and orthorhombic LiFePO4. The structural characterization and micro-morphology of FePO4 2H2O and as-prepared LiFePO4@C are performed by the scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images. The FePO4 2H2O has the morphology of nano-flake particles with good dispersion. After carbon coating, LiFePO4@C composite with mean carbon thickness of about 3[Formula: see text]nm exhibits a high discharge capacity of [Formula: see text] at 0.2[Formula: see text]C and [Formula: see text] at 10[Formula: see text]C. This method provides a simple, economic and environmentally friendly way to prepare LiFePO4@C cathode material for lithium-ion battery.

The traditional SSD algorithm has a serious abstraction of feature extraction content, which makes it difficult to achieve effective detection of small targets. At the same time, the problem of feature layer fusion is difficult due to different scales. In this paper, an improved SSD based target detection algorithm is proposed. By introducing feature enhancement method, the adjustment steps of high-level feature size are omitted, Which makes it unnecessary to reduce the dimension of features, and at the same time, it uses the multi-scale candidate area which accords with the proportion of pedestrians in the detection network to enhance the feature extraction ability of small targets, effectively improves the accuracy and operation speed of SSD algorithm, and saves the loss of the network.

Using a hand-collected data, we provide evidence of extensive use of commodity derivative in hedging among U.S. oil and gas producers. We find large variations in hedging intensity and hedging profits while on average they generate significant positive profits. The profits relate positively to the intensity of hedging. We further decompose the hedge ratio into two components: the pure hedging component and the market timing component. We find that the hedging profits relate strongly and positively to the market timing component. We also identify a group of firms that can consistently generate profits from their hedging activities. Among firms who actively change their hedging positions, the winners tend to be larger firms. The hedging outcome does not increase equity beta while the pure hedging component tends to decrease equity beta. The positive profits are exclusive for the commodity derivative transactions of the oil and gas producers, while they do not profit from their interest rate or foreign exchange derivative transactions.

In this study, we investigated the effects of interleukin-1β (IL-1β), a typical proinflammatory cytokine on the β-adrenoreceptor-stimulated induction of uncoupling protein 1 (UCP1) expression in adipocytes. IL-1β mRNA expression levels were upregulated in white adipose tissues of obese mice and in RAW264.7 macrophages under conditions designed to mimic obese adipose tissue. Isoproterenol-stimulated induction of UCP1 mRNA expression was significantly inhibited in C3H10T1/2 adipocytes by conditioned medium from lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages in comparison with control conditioned medium. This inhibition was significantly attenuated in the presence of recombinant IL-1 receptor antagonist and IL-1β antibody, suggesting that activated macrophage-derived IL-1β is an important cytokine for inhibition of β-adrenoreceptor-stimulated UCP1 induction in adipocytes. IL-1β suppressed isoproterenol-induced UCP1 mRNA expression in C3H10T1/2 adipocytes, and this effect was partially but significantly abrogated by inhibition of extracellular signal-regulated kinase (ERK). IL-1β also suppressed the isoproterenol-induced activation of the UCP1 promoter and transcription factors binding to the cAMP response element. Moreover, intraperitoneal administration of IL-1β suppressed cold-induced UCP1 expression in adipose tissues. These findings suggest that IL-1β upregulated in obese adipose tissues suppresses β-adrenoreceptor-stimulated induction of UCP1 expression through ERK activation in adipocytes.

Controlled syntheses of PtNi metal nanocrystals with unique structures for catalyzing oxygen reduction reactions (ORRs) have attracted great interest. Here, we report the one-step synthesis of single-crystal PtNi octahedra with in situ-developed highly concave features and self-confined composition that are optimal for ORR. Detailed studies revealed that the Pt-rich seeding, subsequent Pt/Ni co-reduction, and Pt–Ni interfusion resulted in uniform single-crystal PtNi octahedra, and that the combination of Ni facet segregation and oxygen etching of a Ni-rich surface led to the concavity and confined Ni content. The concave PtNi nanocrystals exhibited much higher ORR performance than the commercially available Pt/C catalyst in terms of both specific activity (29.1 times higher) and mass activity (12.9 times higher) at 0.9 V (vs. reversible hydrogen electrode (RHE)). The performance was also higher than that of PtNi octahedra without concavity, confirming that the higher activity was closely related to its morphology. Moreover, the concave octahedra also exhibited remarkable stability in ORR (93% mass activity remained after 10,000 cycles between 0.6 and 1.1 V vs. RHE) owing to the passivation of the unstable sites.

Silicon nanowires (SiNWs) have been widely studied as light harvesting antennas in photocatalysts due to their ability to absorb broad-spectrum solar radiation, but they are typically limited by poor photoelectrochemical stability. Here, we report the synthesis of reduced graphene oxide-SiNW (rGO-SiNW) heterostructures to achieve greatly improved photocatalytic activity and stability. The SiNWs were synthesized through a metal-assisted electroless etching process and functionalized with reduced graphene oxide (rGO) flakes through a chemical absorption process. Here, the rGO not only functions as a physical protection layer to isolate the SiNWs from the harsh electrochemical environment but also serves as a charge mediator to facilitate the charge separation and transport processes. Furthermore, the rGO may also function as a redox catalyst to ensure efficient utilization of photo-carriers for the desired chemical reactions. Photocatalytic dye degradation studies show that the photoactivity of the heterostructures can be significantly enhanced with an initial activation process and maintained without apparent decay over repeated reaction cycles. Electrochemical and photoelectrochemical studies indicate that the enhanced photoactivity and photostability can be attributed to the more efficient separation of photoexcited charge carriers in SiNWs and the reduced self-oxidation of the surface of the SiNWs during the photocatalytic dye degradation process. The ability to significantly improve the photocatalytic activity and stability in rGO-SiNW heterostructures can not only lead to more opportunities for the application of silicon-based photocatalysts/photoelectrodes for solar energy harvesting but also provide new insights into the stabilization of other unstable photocatalytic systems.

Titanium oxide (TiO2) represents one of most widely studied materials for photoelectrochemical (PEC) water splitting but is severely limited by its poor efficiency in the visible light range. Here, we report a significant enhancement of visible light photoactivity in nitrogen-implanted TiO2 (N-TiO2) nanowire arrays. Our systematic studies show that a post-implantation thermal annealing treatment can selectively enrich the substitutional nitrogen dopants, which is essential for activating the nitrogen implanted TiO2 to achieve greatly enhanced visible light photoactivity. An incident photon to electron conversion efficiency (IPCE) of ∼10% is achieved at 450 nm in N-TiO2 without any other cocatalyst, far exceeding that in pristine TiO2 nanowires (∼0.2%). The integration of oxygen evolution reaction (OER) cocatalyst with N-TiO2 can further increase the IPCE at 450 nm to ∼17% and deliver an unprecedented overall photocurrent density of 1.9 mA/cm2, by integrating the IPCE spectrum with standard AM 1.5G solar s...

A carbene-catalyzed enantioselective addition of benzylic carbon to α,β-unsaturated acyl azolium intermediate generated via N-heterocyclic carbene catalysis is disclosed. This addition is followed by a stereoselective Mannich reaction and a chemo-selective lactam formation cascade to afford pyrrolo[3,2-c]quinolones as the products with excellent yields and optical purities. This work constitutes an effective asymmetric benzyl sp3-carbon functionalization and single-step rapid access to multicyclic heterocycles bearing four contiguous chiral centers. NRF (Natl Research Foundation, S’pore) ASTAR (Agency for Sci., Tech. and Research, S’pore) MOE (Min. of Education, S’pore) Accepted version

Obesity is associated with inflammatory arthritis (IA) but the mechanisms linking adipose tissue to joint inflammation are enigmatic. We explored this issue by selectively expressing diphtheria toxin in adipose tissue yielding “fat-free” (FF) mice completely lacking white and brown fat. FF mice exhibit systemic neutrophilia and elevated serum acute phase proteins, suggesting predisposition to severe IA. Surprisingly, however, FF mice are completely resistant to K/BxN serum-induced IA, maintaining normal ankle and paw thickness and no evidence of enhanced osteoclastogenesis or periarticular bone destruction. Despite their robust systemic basal neutrophilia, no neutrophil infiltration into joints of FF mice occurs when challenged with K/BxN serum. Absence of adiponectin, leptin or both has no effect on joint disease but deletion of the adipokine, adipsin (complement factor D) completely prevents serum-induced IA. Confirming fat-ex-pressed adipsin modulates the disorder, transplantation of WT adipose tissue into FF mice is sufficient to restore susceptibility to IA, whereas recipients of adipsin-deficient fat remain resistant. Our studies provide the first direct evi-dence that adipose tissue regulates development of IA and reveal a previously unrecognized pathway in which adipocytes modify neutrophil responses in distant tissues by producing adipsin.

A Cu2O nanoparticle catalyzed borylation of activated and unactivated alkyl bromides is developed, using bis(pinacolato)diboron as a boron source. To the best of our knowledge this is the first report of a heterogeneous Cu2O nanocatalyst applied in the direct synthesis of primary and secondary alkylboronic esters. Our catalytic system features mild reaction conditions, high yield (nearly 100%) and the absence of ligands which otherwise are essential in homogenous catalysis.

Although the Apiaceae herb family has been traditionally used for the management of type 2 diabetes, its molecular mechanism has not been clarified. Coumarin derivatives, which are abundant in plants of the Apiaceae family, were evaluated for their effects on adipogenesis. We found that suksdorfin significantly promoted adipocyte differentiation and enhanced production of adiponectin, an anti-diabetic adipokine. We also demonstrated that suksdorfin activates peroxisome proliferator-activated receptor gamma (PPARγ), a master regulator of adipogenesis. Furthermore, we showed metabolic disorders in obese diabetic KK-Ay mice were attenuated by suksdorfin feeding. Suksdorfin intake induced adipocyte miniaturization and increased expression levels of PPARγ target genes related to adipocyte differentiation. These results indicated that suksdorfin induces adipogenesis in white adipose tissue (WAT) via the activation of PPARγ, leading to improvement of obesity-induced metabolic disorders. Therefore, suksdorfin-mediated amelioration of WAT dysfunctions might be responsible for the anti-diabetic effects of traditional herbal medicine therapy with Apiaceae.

Controlling the morphology of nanocrystals (NCs) is of paramount importance for both fundamental studies and practical applications. The morphology of NCs is determined by the seed structure and the following facet growth. While means for directing facet formation in NC growth have been extensively studied, rational strategies for the production of NCs bearing structure defects in seeds have been much less explored. Here, we report mechanistic investigations of high density twin formation induced by specific peptides in platinum (Pt) NC growth, on the basis of which we derive principles that can serve as guidelines for the rational design of molecular surfactants to introduce high yield twinning in noble metal NC syntheses. Two synergistic factors are identified in producing twinned Pt NCs with the peptide: (1) the altered reduction kinetics and crystal growth pathway as a result of the complex formation between the histidine residue on the peptide and Pt ions, and (2) the preferential stabilization of {111} planes upon the formation of twinned seeds. We further apply the discovered principles to the design of small organic molecules bearing similar binding motifs as ligands/surfactants to create single and multiple twinned Pd and Rh NCs. Our studies demonstrate the rich information derived from biomimetic synthesis and the broad applicability of biomimetic principles to NC synthesis for diverse property tailoring.

An improved process of the novel HMG CoA reductase inhibitor SIPI-4884 has been developed for early preclinical pharmacology and safety studies, and it was made up with an efficient nine-step and s...

Reinventing the wheel: Bimetallic AuPd nanowheels, a freestanding form of 2D AuPd nanostructures, were synthesized in a one-pot process. The well-defined and tunable surface plasmon resonance displayed by these nanowheels was exploited in a unique catalytic process in which light energy was used to drive catalytic reactions, such as the Suzuki coupling, with much higher efficiency than that of the conventional heating process.

A facile strategy to Pt3Ni nanocrystals with highly porous features is developed. The integration of a high surface area and rich step/edge atoms endows the nanocrystals with an impressive oxygen reduction reaction (ORR) specific activity and mass activity. These nanocrystals are more stable in ORR and show a small activity change after 6000 potential sweeps. This is a promising material for practical electrocatalytic applications.

Gut microbiota can regulate the host energy metabolism; however, the underlying mechanisms that could involve gut microbiota-derived compounds remain to be understood. Therefore, in this study, we investigated the effects of KetoA [10-oxo-12(

Channeling a good catalyst: Highly porous palladium nanostructures (pPdNs) with perpendicular pore channels were prepared under mild conditions. The combination of high surface area and rich edge/corner atoms gives pPdNs better catalytic performance than known Pd catalysts for the hydrogenation of nitrobenzene and styrene and the Suzuki coupling reaction.

Molecular ligand modulation of Pd nanoparticle catalysts achieves exceptional activity and stability., Metallic nanoparticles are emerging as an exciting class of heterogeneous catalysts with the potential advantages of exceptional activity, stability, recyclability, and easier separation than homogeneous catalysts. The traditional colloid nanoparticle syntheses usually involve strong surface binding ligands that could passivate the surface active sites and result in poor catalytic activity. The subsequent removal of surface ligands could reactivate the surface but often leads to metal ion leaching and/or severe Ostwald ripening with diminished catalytic activity or poor stability. Molecular ligand engineering represents a powerful strategy for the design of homogeneous molecular catalysts but is insufficiently explored for nanoparticle catalysts to date. We report a systematic investigation on molecular ligand modulation of palladium (Pd) nanoparticle catalysts. Our studies show that β-functional groups of butyric acid ligand on Pd nanoparticles can significantly modulate the catalytic reaction process to modify the catalytic activity and stability for important aerobic reactions. With a β-hydroxybutyric acid ligand, the Pd nanoparticle catalysts exhibit exceptional catalytic activity and stability with an unsaturated turnover number (TON) >3000 for dehydrogenative oxidation of cyclohexenone to phenol, greatly exceeding that of homogeneous Pd(II) catalysts (TON, ~30). This study presents a systematic investigation of molecular ligand modulation of nanoparticle catalysts and could open up a new pathway toward the design and construction of highly efficient and robust heterogeneous catalysts through molecular ligand engineering.