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The gait rehabilitation knee exoskeleton is an advanced rehabilitative assistive device designed to help patients with knee joint dysfunction regain normal gait through training and activity support. This paper introduces a design framework based on the process knowledge representation method to optimize the design and control efficiency of the knee exoskeleton. This framework integrates knowledge of design objects and processes, specifically including requirements, functions, principle work areas, and the representation and multi-dimensional dynamic mapping of the Behavior-Structure (RFPBS) matrix, achieving multi-dimensional dynamic mapping of the knee exoskeleton. This method incorporates biomechanical and physiological knowledge from the rehabilitation process to more effectively simulate and support gait movements during rehabilitation. Research results indicate that the knee rehabilitation exoskeleton design, based on the RFPBS process knowledge representation model, accomplishes multi-dimensional dynamic mapping, providing a scientific basis and effective support for the rehabilitation of patients with knee joint dysfunction.

The adenosine A 3 receptor (A 3 AR), a key member of the G protein-coupled receptor family, is a promising therapeutic target for inflammatory and cancerous conditions. The selective A 3 AR agonists, CF101 and CF102, are clinically significant, yet their recognition mechanisms remained elusive. Here we report the cryogenic electron microscopy structures of the full-length human A 3 AR bound to CF101 and CF102 with heterotrimeric G i protein in complex at 3.3-3.2 Å resolution. These agonists reside in the orthosteric pocket, forming conserved interactions via their adenine moieties, while their 3-iodobenzyl groups exhibit distinct orientations. Functional assays reveal the critical role of extracellular loop 3 in A 3 AR's ligand selectivity and receptor activation. Key mutations, including His 3.37 , Ser 5.42 , and Ser 6.52 , in a unique sub-pocket of A 3 AR, significantly impact receptor activation. Comparative analysis with the inactive A 2A AR structure highlights a conserved receptor activation mechanism. Our findings provide comprehensive insights into the molecular recognition and signaling of A 3 AR, paving the way for designing subtype-selective adenosine receptor ligands., (© 2024. The Author(s).)

Digital image correlation (DIC) technology has been widely used in high-temperature measurement fields. However, due to the complexity of high-temperature environments, there are many interference factors that limit the development of high-temperature DIC technology, among which thermal disturbance is one of the most significant factors that severely affects the measurement accuracy of high-temperature DIC. In this paper, a multi-channel separation technique combined with a low-cost laser speckle device is proposed to eliminate thermal disturbance errors in high-temperature DIC measurements. First, a blue laser speckle generation system is independently designed to produce the most suitable speckle particles, and the best laser speckle is determined and projected onto the blue background white spot pattern. Then a green LED illuminates the sample to provide illumination for the sample's own grayscale characteristics. A color camera collects photos, and the obtained images are processed with channel separation to extract and calculate the displacement of different channels. Finally, the displacement fields of the green and blue channels are subtracted to separate the thermal disturbance error and correct the measurement values. In this paper, a laser speckle projection system is first assembled, followed by a comprehensive evaluation of the projected speckle and, finally, a DIC experimental system is constructed for verification experiments at both room temperature and high temperature, and the corrected values are compared with the true values. The results show that the corrected values are highly consistent with the true values, which verifies the reliability of the proposed method.

Niacin, an age-old lipid-lowering drug, acts through the hydroxycarboxylic acid receptor 2 (HCAR2), a G-protein-coupled receptor (GPCR). Yet, its use is hindered by side effects like skin flushing. To address this, specific HCAR2 agonists, like MK-6892 and GSK256073, with fewer adverse effects have been created. However, the activation mechanism of HCAR2 by niacin and these new agonists is not well understood. Here, we present three cryoelectron microscopy structures of Gi-coupled HCAR2 bound to niacin, MK-6892, and GSK256073. Our findings show that different ligands induce varying binding pockets in HCAR2, influenced by aromatic amino acid clusters (W91 ECL1 , H161 4.59 , W188 5.38 , H189 5.39 , and F193 5.43 ) from receptors ECL1, TM4, and TM5. Additionally, conserved residues R111 3.36 and Y284 7.43 , unique to the HCA receptor family, likely initiate activation signal propagation in HCAR2. This study provides insights into ligand recognition, receptor activation, and G protein coupling mediated by HCAR2, laying the groundwork for developing HCAR2-targeted drugs., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

In this the antibacterial of quercetin against Alicyclobacillus acidoterrestris was evaluated by measuring the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). Subsequently, the effect of quercetin on A. acidoterrestris cell membrane was evaluated through scanning electron microscopy (SEM), surface hydrophobicity determination, diacetate fluorescein staining and propidium iodide (PI) staining. Additionally, the effects of quercetin on intracellular macromolecules and cell metabolism were explored by measuring the culture medium protein, bacterial protein and intracellular sodium and potassium adenosine triphosphate (ATP) enzyme activity. The results revealed that quercetin exhibited the MIC and MBC values of 100 ug/mL and 400 ug/mL, respectively, against A. acidoterrestris . The SEM results revealed that quercetin could induce irreversible damage to the cell membrane effectively. Moreover, quercetin could enhance the surface hydrophobicity of A. acidoterrestris . The results of flow cytometry and fluorescence microscopy analyses revealed that quercetin could promote cell damage by altering the cell membrane permeability of A. acidoterrestris , inducing the release of nucleic acid substances from the cells. Furthermore, the determination of protein content in the culture medium, bacterial protein content, and the Na(+)/K(+)-ATPase activity demonstrated that quercetin could reduce the intracellular protein content and impedes protein expression and ATPase synthesis effectively, leading to apoptosis., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Liang, Tu, Li, Sun, Zhao, Ran, Jiao, Huang and Li.)

Class B G-protein-coupled receptors (GPCRs), including glucagon-like peptide 1 receptor (GLP1R) and parathyroid hormone 1 receptor (PTH1R), are important drug targets 1-5 . Injectable peptide drugs targeting these receptors have been developed, but orally available small-molecule drugs remain under development 6,7 . Here we report the high-resolution structure of human PTH1R in complex with the stimulatory G protein (G s ) and a small-molecule agonist, PCO371, which reveals an unexpected binding mode of PCO371 at the cytoplasmic interface of PTH1R with G s . The PCO371-binding site is totally different from all binding sites previously reported for small molecules or peptide ligands in GPCRs. The residues that make up the PCO371-binding pocket are conserved in class B GPCRs, and a single alteration in PTH2R and two residue alterations in GLP1R convert these receptors to respond to PCO371. Functional assays reveal that PCO371 is a G-protein-biased agonist that is defective in promoting PTH1R-mediated arrestin signalling. Together, these results uncover a distinct binding site for designing small-molecule agonists for PTH1R and possibly other members of the class B GPCRs and define a receptor conformation that is specific only for G-protein activation but not arrestin signalling. These insights should facilitate the design of distinct types of class B GPCR small-molecule agonist for various therapeutic indications., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

The dual functions of TMEM16F as Ca 2+ -activated ion channel and lipid scramblase raise intriguing questions regarding their molecular basis. Intrigued by the ability of the FDA-approved drug niclosamide to inhibit TMEM16F-dependent syncytia formation induced by SARS-CoV-2, we examined cryo-EM structures of TMEM16F with or without bound niclosamide or 1PBC, a known blocker of TMEM16A Ca 2+ -activated Cl - channel. Here, we report evidence for a lipid scrambling pathway along a groove harboring a lipid trail outside the ion permeation pore. This groove contains the binding pocket for niclosamide and 1PBC. Mutations of two residues in this groove specifically affect lipid scrambling. Whereas mutations of some residues in the binding pocket of niclosamide and 1PBC reduce their inhibition of TMEM16F-mediated Ca 2+ influx and PS exposure, other mutations preferentially affect the ability of niclosamide and/or 1PBC to inhibit TMEM16F-mediated PS exposure, providing further support for separate pathways for ion permeation and lipid scrambling., (© 2023. Springer Nature Limited.)

Phosphorylation of G-protein-coupled receptors (GPCRs) by GPCR kinases (GRKs) desensitizes G-protein signalling and promotes arrestin signalling, which is also modulated by biased ligands 1-6 . The molecular assembly of GRKs on GPCRs and the basis of GRK-mediated biased signalling remain largely unknown owing to the weak GPCR-GRK interactions. Here we report the complex structure of neurotensin receptor 1 (NTSR1) bound to GRK2, Gα q and the arrestin-biased ligand SBI-553 7 . The density map reveals the arrangement of the intact GRK2 with the receptor, with the N-terminal helix of GRK2 docking into the open cytoplasmic pocket formed by the outward movement of the receptor transmembrane helix 6, analogous to the binding of the G protein to the receptor. SBI-553 binds at the interface between GRK2 and NTSR1 to enhance GRK2 binding. The binding mode of SBI-553 is compatible with arrestin binding but clashes with the binding of Gα q protein, thus providing a mechanism for its arrestin-biased signalling capability. In sum, our structure provides a rational model for understanding the details of GPCR-GRK interactions and GRK2-mediated biased signalling., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

Digital shearography is a non-contact, whole-field, and high-accuracy laser-based optical interferometric method. It is widely used in the field of non-destructive testing and material evaluation. Dual-shearing DS, as the state-of-the-art method, can detect defects or measure the derivative of deformation in two sensitive directions. Most existing dual-shearing DS is realized with a bulky Michelson or Mach-Zehnder interferometer; recently, the usage of a spatial light modulator (SLM) in DS offers a new approach to designing a simple and light shearographic system. However, prior proposed SLM-based DS requires multiple shots for the phase map acquisition, with the classic temporal phase-shift (TPS) technique severely limiting its applications. This paper proposes a novel, to our best knowledge, one-shot dual-shearing DS by creating a dual-stripe pattern in the SLM. Two separate phase maps, with different sensitive directions, were acquired simultaneously via the spatial phase-shift technique. The measurement can be easily done within a single shot in its compact and light body. Moreover, the shearing amount of the two sensitive directions can be set independently and precisely. These advantages promote that the proposed system can be applied in various applications, especially for dynamic and complicated composite material testing. A detailed theory and experimental validation are described.

The possibility of using a line-scan digital CMOS camera as a photodetector in a multi-beam heterodyne differential laser Doppler vibration sensor has been investigated. Application of the line-scan CMOS camera allows for selection of a different number of beams for a particular application in the sensor design, and for a compact design of the sensor. It was demonstrated that a limitation of the maximum measured velocity caused by the camera limited line rate can be overcome by selecting the beams separation on the object and the value of shear between images on the camera.

To protect themselves from host attack, numerous jumbo bacteriophages establish a phage nucleus-a micron-scale, proteinaceous structure encompassing the replicating phage DNA. Bacteriophage and host proteins associated with replication and transcription are concentrated inside the phage nucleus while other phage and host proteins are excluded, including CRISPR-Cas and restriction endonuclease host defense systems. Here, we show that nucleus fragments isolated from ϕPA3 infected Pseudomonas aeruginosa form a 2-dimensional lattice, having p2 or p4 symmetry. We further demonstrate that recombinantly purified primary Phage Nuclear Enclosure (PhuN) protein spontaneously assembles into similar 2D sheets with p2 and p4 symmetry. We resolve the dominant p2 symmetric state to 3.9 Å by cryo-EM. Our structure reveals a two-domain core, organized into quasi-symmetric tetramers. Flexible loops and termini mediate adaptable inter-tetramer contacts that drive subunit assembly into a lattice and enable the adoption of different symmetric states. While the interfaces between subunits are mostly well packed, two are open, forming channels that likely have functional implications for the transport of proteins, mRNA, and small molecules., (© 2023. The Author(s).)

Multi-beam laser Doppler vibrometers (MB-LDVs) have an advantage over scanning single-beam laser Doppler vibrometers (LDVs) due to the reduction in measurement time and their ability to measure non-stationary and transient events. However, the number of simultaneously interrogated points in current MB-LDVs is limited due to the complexity of the electronic hardware, which increases with the number of measurement channels. Recent developments of high-speed line-scan CMOS cameras suggest that their use in MB-LDVs can reduce the hardware complexity and increase the number of measurement channels. We developed a MB-LDV based on a digital line-scan CMOS camera that simultaneously measures vibrations on a linear array of 99 points. The experimental setup and performance of the developed MB-LDV are discussed in this paper.

Parkinson's disease (PD) is the second most common chronic neurodegenerative disease globally; however, it lacks effective treatment at present. Focused ultrasound (FUS) combined with microbubbles could increase the efficacy of drug delivery to specific brain regions and is becoming a promising technology for the treatment of central nervous system diseases. In this study, we explored the therapeutic potential of FUS-mediated blood-brain barrier (BBB) opening of the left striatum to deliver gastrodin (GAS) in a subacute PD mouse model induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). The concentration of GAS in the left hemisphere was detected by ultra-high performance liquid chromatography electrospray Q-Orbitrap mass spectrometry (UHPLC/ESI Q-Orbitrap) and the distribution of tyrosine hydroxylase (TH) neurons was detected by immunohistochemical staining. The expression of TH, Dopamine transporter (DAT), cleaved-caspase-3, B-cell lymphoma 2 (Bcl-2), brain-derived neurotrophic factor (BDNF), postsynaptic density protein 95 (PSD-95), and synaptophysin (SYN) protein were detected by western blotting. Analysis showed that the concentration of GAS in the left hemisphere of PD mice increased by approximately 1.8-fold after the BBB was opened. FUS-mediated GAS delivery provided optimal neuroprotective effects and was superior to the GAS or FUS control group. In addition, FUS enhanced GAS delivery significantly increased the expression of Bcl-2, BDNF, PSD-95, and SYN protein in the left striatum ( P < 0.05) and reduced the levels of cleaved-caspase-3 remarkably ( P = 0.001). In conclusion, the enhanced delivery by FUS effectively strengthened the protective effect of GAS on dopaminergic neurons which may be related to the reinforcement of the anti-apoptotic activity and the expression of synaptic-related proteins in the striatum. Data suggests that FUS-enhanced GAS delivery may represent a new strategy for PD treatment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Wang, Luo, Li, Liao, Liao, Chen, Chen and Ao.)

Among metals used for CO 2 electroreduction in water, Cu appears to be unique in its ability to produce C2+ products like ethylene. Bimetallic combinations of Cu with other metals have been investigated with the goal of steering selectivity via creating a tandem pathway through the CO intermediate or by changing the surface electronic structure. Here, we demonstrate a facile cation exchange method to synthesize Ag/Cu electrocatalysts for CO 2 reduction using Cu sulfides as a growth template. Beginning with Cu 2- x S nanosheets (C-nano-0, 100 nm lateral dimension, 14 nm thick), varying the Ag + concentration in the exchange solution produces a gradual change in crystal structure from Cu 7 S 4 to Ag 2 S, as the Ag/Cu mass ratio varies from 0.3 to 25 (CA-nano- x , x indicating increasing Ag fraction). After cation exchange, the nanosheet morphology remains but with increased shape distortion as the Ag fraction is increased. Interestingly, the control (C-nano-0) and cation exchanged nanosheets have very high faradaic efficiency for producing formate at low overpotential (-0.2 V vs. RHE). The primary effect of Ag incorporation is increased production of C2+ products at -1.0 V vs. RHE compared with C-nano-0, which primarily produces formate. Cation exchange can also be used to modify the surface of Cu foils. A two-step electro-oxidation/sulfurization process was used to form Cu sulfides on Cu foil (C-foil- x ) to a depth of a few 10 s of microns. With lower Ag + concentrations, cation exchange produces uniformly dispersed Ag; however, at higher concentrations, Ag particles nucleate on the surface. During CO 2 electroreduction testing, the product distribution for Ag/Cu sulfides on Cu foil (CA-foil- x-y ) changes in time with an initial increase in ethylene and methane production followed by a decrease as more H 2 is produced. The catalysts undergo a morphology evolution towards a nest-like structure which could be responsible for the change in selectivity. For cation-exchanged nanosheets (CA-nano- x ), pre-reduction at negative potentials increases the CO 2 reduction selectivity compared to tests of as-synthesized material, although this led to the aggregation of nanosheets into filaments. Both types of bimetallic catalysts are capable of selective reduction of CO 2 to multi-carbon products, although the optimal configurations appear to be metastable., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The COVID-19 pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a grave threat to public health and the global economy. SARS-CoV-2 is closely related to the more lethal but less transmissible coronaviruses SARS-CoV-1 and Middle East respiratory syndrome coronavirus (MERS-CoV). Here, we have carried out comparative viral-human protein-protein interaction and viral protein localization analyses for all three viruses. Subsequent functional genetic screening identified host factors that functionally impinge on coronavirus proliferation, including Tom70, a mitochondrial chaperone protein that interacts with both SARS-CoV-1 and SARS-CoV-2 ORF9b, an interaction we structurally characterized using cryo-electron microscopy. Combining genetically validated host factors with both COVID-19 patient genetic data and medical billing records identified molecular mechanisms and potential drug treatments that merit further molecular and clinical study., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Tuning the performance of nanoparticle (NP) catalysts by controlling the NP surface strain has evolved as an important strategy to optimize NP catalysis in many energy conversion reactions. Here, we present our new study on using an eigenforce model to predict and experiments to verify the strain-induced catalysis enhancement of the oxygen reduction reaction (ORR) in the presence of L1 0 -CoMPt NPs (M = Mn, Fe, Ni, Cu, Ni). The eigenforce model allowed us to predict anisotropic (that is, two-dimensional) strain levels on distorted Pt(111) surfaces. Experimentally, by preparing a series of 5 nm L1 0 -CoMPt NPs, we could push the ORR catalytic activity of these NPs toward the optimum region of the theoretical two-dimensional volcano plot predicted for L1 0 -CoMPt. The best ORR catalyst in the alloy NP series we studied is L1 0 -CoNiPt, which has a mass activity of 3.1 A/mg Pt and a specific activity of 9.3 mA/cm 2 at room temperature with only 15.9% loss of mass activity after 30 000 cycles at 60 °C in 0.1 M HClO 4 .

Osteocytes are mechanosensitive bone cells, but little is known about their effects on tumor cells in response to mechanical stimulation. We treated breast cancer cells with osteocyte-derived conditioned medium (CM) and fluid flow-treated conditioned medium (FFCM) with 0.25 Pa and 1 Pa shear stress. Notably, CM and FFCM at 0.25 Pa induced the mesenchymal-to-epithelial transition (MET), but FFCM at 1 Pa induced the epithelial-to-mesenchymal transition (EMT). This suggested that the effects of fluid flow on conditioned media depend on flow intensity. Fluorescence resonance energy transfer (FRET)-based evaluation of Src activity and vinculin molecular force showed that osteopontin was involved in EMT and MET switching. A mouse model of tumor-induced osteolysis was tested using dynamic tibia loadings of 1, 2, and 5 N. The low 1 N loading suppressed tumor-induced osteolysis, but this beneficial effect was lost and reversed with loads at 2 and 5 N, respectively. Changing the loading intensities in vivo also led to changes in serum TGFβ levels and the composition of tumor-associated volatile organic compounds in the urine. Collectively, this study demonstrated the critical role of intensity-dependent mechanotransduction and osteopontin in tumor-osteocyte communication, indicating that a biophysical factor can tangibly alter the behaviors of tumor cells in the bone microenvironment., Competing Interests: Competing interestsThe authors declare no competing interests., (© The Author(s) 2020.)

Understanding the Cu-catalyzed electrochemical CO 2 reduction reaction (CO 2 RR) under ambient conditions is both fundamentally interesting and technologically important for selective CO 2 RR to hydrocarbons. Current Cu catalysts studied for the CO 2 RR can show high activity but tend to yield a mixture of different hydrocarbons, posing a serious challenge on using any of these catalysts for selective CO 2 RR. Here, we report a new perovskite-type copper(I) nitride (Cu 3 N) nanocube (NC) catalyst for selective CO 2 RR. The 25 nm Cu 3 N NCs show high CO 2 RR selectivity and stability to ethylene (C 2 H 4 ) at -1.6 V (vs reversible hydrogen electrode (RHE)) with the Faradaic efficiency of 60%, mass activity of 34 A/g, and C 2 H 4 /CH 4 molar ratio of >2000. More detailed electrochemical characterization, X-ray photon spectroscopy, and density functional theory calculations suggest that the high CO 2 RR selectivity is likely a result of (100) Cu(I) stabilization by the Cu 3 N structure, which favors CO-CHO coupling on the (100) Cu 3 N surface, leading to selective formation of C 2 H 4 . Our study presents a good example of utilizing metal nitrides as highly efficient nanocatalysts for selective CO 2 RR to hydrocarbons that will be important for sustainable chemistry/energy applications.

Circulating cell-free tumor DNA (ctDNA) is a promising biomarker in cancer. Ultrasensitive technologies enable detection of low (< 0.1%) mutant allele frequencies, a pre-requisite to fully utilize the potential of ctDNA in cancer diagnostics. In addition, the entire liquid biopsy workflow needs to be carefully optimized to enable reliable ctDNA analysis. Here, we discuss important considerations for ctDNA detection in plasma. We show how each experimental step can easily be evaluated using simple quantitative PCR assays, including detection of cellular DNA contamination and PCR inhibition. Furthermore, ctDNA assay performance is also demonstrated to be affected by both DNA fragmentation and target sequence. Finally, we show that quantitative PCR is useful to estimate the required sequencing depth and to monitor DNA losses throughout the workflow. The use of quality control assays enables the development of robust and standardized workflows that facilitate the implementation of ctDNA analysis into clinical routine.

We report a simple strategy to synthesize anisotropic SmCo5 nanoplates. The strategy involves the pre-synthesis of 125 × 12 nm Sm(OH)3 nanorods and 10 nm Co nanoparticles followed by the self-assembly of these nanorods and nanoparticles into Sm(OH)3-Co nanocomposites. Once embedded in a CaO matrix, the nanocomposite is subjected to high temperature (850 °C) annealing in the presence of Ca, leading to the formation of 125 × 10 nm SmCo5 nanoplates, which are dispersible in ethanol, allowing the alignment in epoxy resin under a 20 kOe magnetic field. The aligned SmCo5 nanoplates show a square hysteresis behavior with room temperature coercivity reaching 30.1 kOe, which is among the highest values ever reported for SmCo5 made from chemical methods. This work provides a new approach to high-performance anisotropic SmCo5 for permanent magnetic applications.

Stabilizing a 3d-transition metal component M from an MPd alloy structure in an acidic environment is key to the enhancement of MPd catalysis for various reactions. Here we demonstrate a strategy to stabilize Cu in 5 nm CuPd nanoparticles (NPs) by coupling the CuPd NPs with perovskite-type WO 2.72 nanorods (NRs). The CuPd NPs are prepared by controlled diffusion of Cu into Pd NPs, and the coupled CuPd/WO 2.72 are synthesized by growing WO 2.72 NRs in the presence of CuPd NPs. The CuPd/WO 2.72 can stabilize Cu in 0.1 M HClO 4 solution and, as a result, they show Cu, Pd composition dependent activity for the electrochemical oxidation of formic acid in 0.1 M HClO 4 + 0.1 M HCOOH. Among three different CuPd/WO 2.72 studied, the Cu 48 Pd 52 /WO 2.72 is the most efficient catalyst, with its mass activity reaching 2086 mA/mg Pd in a broad potential range of 0.40 to 0.80 V (vs RHE) and staying at this value after the 12 h chronoamperometry test at 0.40 V. The synthesis can be extended to obtain other MPd/WO 2.72 (M = Fe, Co, Ni), making it possible to study MPd-WO 2.72 interactions and MPd stabilization on enhancing MPd catalysis for various chemical reactions.

We report a seed-mediated growth of 2.3 nm AgPd nanoparticles (NPs) in the presence of 40 × 5 nm WO 2.72 nanorods (NRs) for the synthesis of AgPd/WO 2.72 composites. The strong interactions between AgPd NPs and WO 2.72 NRs make the composites, especially the Ag 48 Pd 52 /WO 2.72 , catalytically active for dehydrogenation of formic acid (TOF = 1718 h -1 and E a = 31 kJ/mol) and one-pot reactions of formic acid, 2-nitrophenol, and aldehydes into benzoxazoles in near quantitative yields under mild conditions. The catalysis can also be extended to the one-pot reactions of ammonium formate, 2-nitroacetophenone, and aldehyde for high yield syntheses of quinazolines. Our studies demonstrate a new catalyst design to achieve a green chemistry approach to one-pot reactions for the syntheses of benzoxazoles and quinazolines.

We synthesize a new type of hybrid Pd/WO 2.72 structure with 5 nm Pd nanoparticles (NPs) anchored on 50 × 5 nm WO 2.72 nanorods. The strong Pd/WO 2.72 coupling results in the lattice expansion of Pd from 0.23 to 0.27 nm and the decrease of Pd surface electron density. As a result, the Pd/WO 2.72 shows much enhanced catalysis toward electrochemical oxidation of formic acid in 0.1 M HClO 4 ; it has a mass activity of ∼1600 mA/mg Pd in a broad potential range of 0.4-0.85 V (vs RHE) and shows no obvious activity loss after a 12 h chronoamperometry test at 0.4 V. Our work demonstrates an important strategy to enhance Pd NP catalyst efficiency for energy conversion reactions.

Teasing apart the effects of selection and demography on genetic polymorphism remains one of the major challenges in the analysis of population genomic data. The traditional approach has been to assume that demography would leave a genome-wide signature, whereas the effect of selection would be local. In the light of recent genomic surveys of sequence polymorphism, several authors have argued that this approach is questionable based on the evidence of the pervasive role of positive selection and that new approaches are needed. In the first part of this review, we give a few empirical and theoretical examples illustrating the difficulty in teasing apart the effects of selection and demography on genomic polymorphism patterns. In the second part, we review recent efforts to detect recent positive selection. Most available methods still rely on an a priori classification of sites in the genome but there are many promising new approaches. These new methods make use of the latest developments in statistics, explore aspects of the data that had been neglected hitherto or take advantage of the emerging population genomic data. A current and promising approach is based on first estimating demographic and genetic parameters, using, e.g., a likelihood or approximate Bayesian computation framework, focusing on extreme outlier regions, and then using an independent method to confirm these. Finally, especially for species where evidence of natural selection has been limited, more experimental and versatile approaches that contrast populations under varied environmental constraints might be more successful compared with species-wide genome scans in search of specific signatures., (© 2011 Blackwell Publishing Ltd.)