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Sluggish surface reaction is a critical factor that strongly governs the efficiency of photocatalytic solar fuel production, particularly in CO 2 -to-ethanol photoconversion. Here, inspired by the principles underlying enzyme catalytic proficiency and specificity, we report a biomimetic photocatalyst that affords superior CO 2 -to-ethanol photoreduction efficiency (5.5 millimoles gram -1 hour -1 in average with 98.2% selectivity) distinctly surpassing the state of the art. The key is to create a class of catalytic pocket, which contains spatially organized NH 2 …Cu-Se(-Zn) multiple functionalities at close range, over ZnSe colloidal quantum wells. Such structure offers a platform to mimic the concerted cooperation between the active site and surrounding secondary/outer coordination spheres in enzyme catalysis. This is manifested by the chemical adsorption and activation of CO 2 via a bent geometry, favorable stabilization toward a variety of important intermediates, promotion of multielectron/proton transfer processes, etc. These results highlight the potential of incorporating enzyme-like features into the design of photocatalysts to overcome the challenges in CO 2 reduction.

Catalytic hydrogenation of CO 2 to value-added fuels and chemicals is of great importance to carbon neutrality but suffers from an activity-selectivity trade-off, leading to limited catalytic performance. Herein, the ZnFeAlO 4 + SAPO-34 composite catalyst was designed, which can simultaneously achieve a CO 2 conversion of 42%, a CO selectivity of 50%, and a C 2 -C 4 = selectivity of 83%, resulting in a C 2 -C 4 = yield of almost 18%. This superior catalytic performance was found to be from the presence of unconventional electron-deficient tetrahedral Fe sites and electron-enriched octahedral Zn sites in the ZnFeAlO 4 spinel, which were active for the CO 2 deoxygenation to CO via the reverse water gas shift reaction, and CO hydrogenation to CH 3 OH, respectively, leading to a route for CO 2 hydrogenation to C 2 -C 4 = , where the kinetics of CO 2 activation can be improved, the mass transfer of CO hydrogenation can be minimized, and the C 2 -C 4 = selectivity can be enhanced via modifying the acid density of SAPO-34. Moreover, the spinel structure of ZnFeAlO 4 possessed a strong ability to stabilize the active Fe and Zn sites even at elevated temperatures, resulting in long-term stability of over 450 h for this process, exhibiting great potential for large-scale applications., Competing Interests: Competing interests statement:The authors declare no competing interest.

Electrochemical ammonia (NH 3 ) synthesis from nitrate reduction (NITRR) offers an appealing solution for addressing environmental concerns and the energy crisis. However, most of the developed electrocatalysts reduce NO 3 - to NH 3 via a hydrogen (H*)-mediated reduction mechanism, which suffers from undesired H*-H* dimerization to H 2 , resulting in unsatisfactory NH 3 yields. Herein, we demonstrate that reversed I 1 Cu 4 single-atom sites, prepared by anchoring iodine single atoms on the Cu surface, realized superior NITRR with a superior ammonia yield rate of 4.36 mg h -1 cm -2 and a Faradaic efficiency of 98.5% under neutral conditions via a proton-coupled electron transfer (PCET) mechanism, far beyond those of traditional Cu sites (NH 3 yield rate of 0.082 mg h -1 cm -2 and Faradaic efficiency of 36.5%) and most of H*-mediated NITRR electrocatalysts. Theoretical calculations revealed that I single atoms can regulate the local electronic structures of adjacent Cu sites in favor of stronger O-end-bidentate NO 3 - adsorption with dual electron transfer channels and suppress the H* formation from the H 2 O dissociation, thus switching the NITRR mechanism from H*-mediated reduction to PCET. By integrating the monolithic I 1 Cu 4 single-atom electrode into a flow-through device for continuous NITRR and in situ ammonia recovery, an industrial-level current density of 1 A cm -2 was achieved along with a NH 3 yield rate of 69.4 mg h -1 cm -2 . This study offers reversed single-atom sites for electrochemical ammonia synthesis with nitrate wastewater and sheds light on the importance of switching catalytic mechanisms in improving the performance of electrochemical reactions., Competing Interests: Competing interests statement:The authors declare no competing interest.

Direct synthesis of dimethyl carbonate (DMC) from CO 2 plays an important role in carbon neutrality, but its efficiency is still far from the practical application, due to the limited understanding of the reaction mechanism and rational design of efficient catalyst. Herein, abundant electron-enriched lattice oxygen species were introduced into CeO 2 catalyst by constructing the point defects and crystal-terminated phases in the crystal reconstruction process. Benefitting from the acid-base properties modulated by the electron-enriched lattice oxygen, the optimized CeO 2 catalyst exhibited a much higher DMC yield of 22.2 mmol g -1 than the reported metal-oxide-based catalysts at the similar conditions. Mechanistic investigations illustrated that the electron-enriched lattice oxygen can provide abundant sites for CO 2 adsorption and activation, and was advantageous of the formation of the weakly adsorbed active methoxy species. These were facilitating to the coupling of methoxy and CO 2 for the key *CH 3 OCOO intermediate formation. More importantly, the weakened adsorption of *CH 3 OCOO on the electron-enriched lattice oxygen can switch the rate-determining-step (RDS) of DMC synthesis from *CH 3 OCOO formation to *CH 3 OCOO dissociation, and lower the corresponding activation barriers, thus giving rise to a high performance. This work provides insights into the underlying reaction mechanism for DMC synthesis from CO 2 and methanol and the design of highly efficient catalysts., (© 2024 Wiley‐VCH GmbH.)

Olefin-linked covalent organic frameworks (COFs) have exhibited great potential in visible-light photocatalysis. In principle, expanding fully conjugated COFs can facilitate light absorption and charge transfer, leading to improved photocatalysis. Herein, three olefin-linked COFs with the same topology are synthesized by combining 2,4,6-trimethyl-1,3,5-triazine (TMT) with 1,3,5-triformylbenzene (TFB), 1,3,5-tris(4-formylphenyl)benzene (TFPB), and 1,3,5-tris(4-formylphenylethynyl)benzene (TFPEB), namely, TMT-TFB-COF, TMT-TFPB-COF, and TMT-TFPEB-COF, respectively. From TMT-TFB-COF to TMT-TFPB-COF, expanding phenyl rings provides only limited expansion for π-conjugation due to the steric effect of structural twisting. However, from TMT-TFPB-COF to TMT-TFPEB-COF, the insertion of acetylenes eliminates the steric effect and provides more delocalized π-electrons. As such, TMT-TFPEB-COF exhibits the best optoelectronic properties among these three olefin-linked COFs. Consequently, the photocatalytic performance of TMT-TFPEB-COF is much better than those of TMT-TFB-COF and TMT-TFPB-COF on the oxidation of organic sulfides into sulfoxides with oxygen. The desirable reusability and substrate compatibility of the TMT-TFPEB-COF photocatalyst are further confirmed. The selective formation of organic sulfoxides over TMT-TFPEB-COF under blue light irradiation proceeds via both electron- and energy-transfer pathways. This work highlights a rational design of expanding the π-conjugation of fully conjugated COFs toward selective visible-light photocatalysis.

Electrochemical nitrate reduction to ammonia offers an attractive solution to environmental sustainability and clean energy production but suffers from the sluggish *NO hydrogenation with the spin-state transitions. Herein, we report that the manipulation of oxygen vacancies can contrive spin-polarized Fe 1 -Ti pairs on monolithic titanium electrode that exhibits an attractive NH 3 yield rate of 272,000 μg h -1 mg Fe -1 and a high NH 3 Faradic efficiency of 95.2% at -0.4 V vs. RHE, far superior to the counterpart with spin-depressed Fe 1 -Ti pairs (51000 μg h -1 mg Fe -1 ) and the mostly reported electrocatalysts. The unpaired spin electrons of Fe and Ti atoms can effectively interact with the key intermediates, facilitating the *NO hydrogenation. Coupling a flow-through electrolyzer with a membrane-based NH 3 recovery unit, the simultaneous nitrate reduction and NH 3 recovery was realized. This work offers a pioneering strategy for manipulating spin polarization of electrocatalysts within pair sites for nitrate wastewater treatment., (© 2024. The Author(s).)

Although considerable efforts towards directly converting syngas to liquid fuels through Fischer-Tropsch synthesis have been made, developing catalysts with low CO 2 selectivity for the synthesis of high-quality gasoline remains a big challenge. Herein, we designed a bifunctional catalyst composed of hydrophobic FeNa@Si-c and HZSM-5 zeolite, which exhibited a low CO 2 selectivity of 14.3 % at 49.8 % CO conversion, with a high selectivity of 62.5 % for gasoline in total products. Molecular dynamic simulations and model experiments revealed that the diffusion of water molecules through hydrophilic catalyst was bidirectional, while the diffusion through hydrophobic catalyst was unidirectional, which were crucial to tune the water-gas shift reaction and control CO 2 formation. This work provides a new fundamental understanding about the function of hydrophobic modification of catalysts in syngas conversion., (© 2023 Wiley-VCH GmbH.)

Nonclassical quantum states are the pivotal features of a quantum system that differs from its classical counterpart. However, the generation and coherent control of quantum states in a macroscopic spin system remain an outstanding challenge. Here we experimentally demonstrate the quantum control of a single magnon in a macroscopic spin system (i.e., 1 mm-diameter yttrium-iron-garnet sphere) coupled to a superconducting qubit via a microwave cavity. By tuning the qubit frequency in situ via the Autler-Townes effect, we manipulate this single magnon to generate its nonclassical quantum states, including the single-magnon state and the superposition of single-magnon state and vacuum (zero magnon) state. Moreover, we confirm the deterministic generation of these nonclassical states by Wigner tomography. Our experiment offers the first reported deterministic generation of the nonclassical quantum states in a macroscopic spin system and paves a way to explore its promising applications in quantum engineering.

Activating water and methanol is crucial in numerous catalytic, electrocatalytic, and photocatalytic reactions. Despite extensive research, the optimal active sites for water/methanol activation are yet to be unequivocally elucidated. Here, we combine transition-state searches and electronic charge analyses on various structurally different materials to identify two features of favorable O-H bond cleavage in H 2 O, CH 3 OH, and hydroxyl: (1) low barriers appear when the charge of H moieties remains approximately constant during the dissociation process, as observed on metal oxides, MXenes, and metal/oxide interfaces. Such favorable kinetics is closely related to adsorbate/substrate hydrogen bonding and is enhanced by nearly linear O-H-O angles and short O-H distances. (2) Fast dissociation is observed when the rotation of O-H bonds is facile, which is favored by weak adsorbate binding and effective orbital overlap. Interestingly, we find that the two features are energetically proportional. Finally, we find conspicuous differences between H 2 O/CH 3 OH and OH activation, which hints toward the use of carefully engineered interfaces., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Propylene epoxidation with O 2 to propylene oxide is a very valuable reaction but remains as a long-standing challenge due to unavailable efficient catalysts with high selectivity. Herein, we successfully explore 27 nm-sized cubic Cu 2 O nanocrystals enclosed with {100} faces and {110} edges as a highly selective catalyst for propylene epoxidation with O 2 , which acquires propylene oxide selectivity of more than 80% at 90-110 °C. Propylene epoxidation with weakly-adsorbed O 2 species at the {110} edge sites exhibits a low barrier and is the dominant reaction occurring at low reaction temperatures, leading to the high propylene oxide selectivity. Such a weakly-adsorbed O 2 species is not stable at high reaction temperatures, and the surface lattice oxygen species becomes the active oxygen species to participate in propylene epoxidation to propylene oxide and propylene partial oxidation to acrolein at the {110} edge sites and propylene combustion to CO 2 at the {100} face sites, which all exhibit high barriers and result in decreased propylene oxide selectivity., (© 2021. The Author(s).)

Schwann cell proliferation, migration and remyelination of regenerating axons contribute to regeneration after peripheral nervous system injury. Lithium promotes remyelination by Schwann cells and improves peripheral nerve regeneration. However, whether lithium modulates other phenotypes of Schwann cells, especially their proliferation and migration remains elusive. In the current study, primary Schwann cells from rat sciatic nerve stumps were cultured and exposed to 0, 5, 10, 15, or 30 mM lithium chloride (LiCl) for 24 hours. The effects of LiCl on Schwann cell proliferation and migration were examined using the Cell Counting Kit-8, 5-ethynyl-2'-deoxyuridine, Transwell and wound healing assays. Cell Counting Kit-8 and 5-ethynyl-2'-deoxyuridine assays showed that 5, 10, 15, and 30 mM LiCl significantly increased the viability and proliferation rate of Schwann cells. Transwell-based migration assays and wound healing assays showed that 10, 15, and 30 mM LiCl suppressed the migratory ability of Schwann cells. Furthermore, the effects of LiCl on the proliferation and migration phenotypes of Schwann cells were mostly dose-dependent. These data indicate that lithium treatment significantly promotes the proliferation and inhibits the migratory ability of Schwann cells. This conclusion will inform strategies to promote the repair and regeneration of peripheral nerves. All of the animal experiments in this study were ethically approved by the Administration Committee of Experimental Animal Center of Nantong University, China (approval No. 20170320-017) on March 2, 2017., Competing Interests: None

The regenerative capacity of peripheral nerves is limited after nerve injury. A number of growth factors modulate many cellular behaviors, such as proliferation and migration, and may contribute to nerve repair and regeneration. Our previous study observed the dynamic changes of genes in L4-6 dorsal root ganglion after rat sciatic nerve crush using transcriptome sequencing. Our current study focused on upstream growth factors and found that a total of 19 upstream growth factors were dysregulated in dorsal root ganglions at 3, 9 hours, 1, 4, or 7 days after nerve crush, compared with the 0 hour control. Thirty-six rat models of sciatic nerve crush injury were prepared as described previously. Then, they were divided into six groups to measure the expression changes of representative genes at 0, 3, 9 hours, 1, 4 or 7 days post crush. Our current study measured the expression levels of representative upstream growth factors, including nerve growth factor, brain-derived neurotrophic factor, fibroblast growth factor 2 and amphiregulin genes, and explored critical signaling pathways and biological process through bioinformatic analysis. Our data revealed that many of these dysregulated upstream growth factors, including nerve growth factor, brain-derived neurotrophic factor, fibroblast growth factor 2 and amphiregulin, participated in tissue remodeling and axon growth-related biological processes Therefore, the experiment described the expression pattern of upstream growth factors in the dorsal root ganglia after peripheral nerve injury. Bioinformatic analysis revealed growth factors that may promote repair and regeneration of damaged peripheral nerves. All animal surgery procedures were performed in accordance with Institutional Animal Care Guidelines of Nantong University and ethically approved by the Administration Committee of Experimental Animals, China (approval No. 20170302-017) on March 2, 2017., Competing Interests: None

Objective: Postoperative delirium (POD) is a common, but severe complication in elderly patients undergoing surgery for colorectal cancer, but the prevalence and potential risk factors for POD were not well established. Therefore, a meta-analysis was preformed to clarify the prevalence and risk factors of POD in patients undergoing surgery for colorectal cancer., Methods: PubMed, Embase, and the Cochrane Library were systematically searched on August 2019. Studies were included if they reported the prevalence and risk factors of POD in patients undergoing colorectal cancer surgery. The guidelines for critically appraising studies of prevalence or incidence of a health problem were used to assess the quality of included studies. Pooled odds ratios (ORs) for individual risk factors were estimated using the Mantel-Haenszel methods in random effect model. Sensitive analyses based on different inclusion criteria were conducted to explore whether the current meta-analysis was enough credible and robust., Results: Seventeen studies totaling 4472 patients undergoing colorectal cancer surgery were included. The pooled prevalence of POD is 14% (95% CI = 12-17%). Twelve significant risk factors were identified in pooled analysis including older age (OR = 1.10), sex (OR = 1.87), history of psychiatric disease (OR = 6.47), comorbidities (OR = 2.17), prognostic nutritional index (OR = 1.12), physical status (OR = 1.27), American Society of Anesthesiologists Score (ASA Scores) (OR = 1.65), history of alcohol abuse (OR = 2.23), postoperative pain management (OR = 1.91), perioperative blood transfusion (OR = 2.37), cognitive status (OR = 1.91), and lower serum level of albumin (OR = 0.58)., Conclusions: POD is a frequent complication in patients undergoing surgery with colorectal cancer. Several risk factors including history of psychiatric disease, transfusion, comorbidities, male gender, and old age were significant predictors for POD.

Extracellular matrix (ECM) deposition following reactive oxygen species (ROS) overproduction has a key role in diabetic nephropathy (DN), thus, antioxidant therapy is considered as a promising strategy for treating DN. Here, we investigated the therapeutic effects of AB38b, a novel synthetic α, β-unsaturated ketone compound, on the oxidative stress (OS) and ECM accumulation in type 2 diabetes mice, and tried to clarify the mechanisms underlying the effects in high glucose (HG, 30 mM)-treated mouse glomerular mesangial cells (GMCs). Type 2 diabetes model was established in mice with high-fat diet feeding combined with streptozocin intraperitoneal administration. The diabetic mice were then treated with AB38b (10, 20, 40 mg· kg -1 · d -1 , ig) or a positive control drug resveratrol (40 mg· kg -1 · d -1 , ig) for 8 weeks. We showed that administration of AB38b or resveratrol prevented the increases in malondialdehyde level, lactate dehydrogenase release, and laminin and type IV collagen deposition in the diabetic kidney. Simultaneously, AB38b or resveratrol markedly lowered the level of Keap1, accompanied by evident activation of Nrf2 signaling in the diabetic kidney. The underlying mechanisms of antioxidant effect of AB38b were explored in HG-treated mouse GMCs. AB38b (2.5-10 μM) or resveratrol (10 μM) significantly alleviated OS and ECM accumulation in HG-treated GMCs. Furthermore, AB38b or resveratrol treatment effectively activated Nrf2 signaling by inhibiting Keap1 expression without affecting the interaction between Keap1 and Nrf2. Besides, AB38b treatment effectively suppressed the ubiquitination of Nrf2. Taken together, this study demonstrates that AB38b ameliorates experimental DN through antioxidation and modulation of Keap1/Nrf2 signaling pathway.

The efficient electrochemical hydrogen evolution reaction (HER) plays a key role in accelerating sustainable H 2 production from water electrolysis, but its large-scale applications are hindered by the high cost of the state-of-the-art Pt catalyst. In this work, submonolayer Pt was controllably deposited on an intermetallic Pd 3 Pb nanoplate (AL-Pt/Pd 3 Pb). The atomic efficiency and electronic structure of the active surface Pt layer were largely optimized, greatly enhancing the acidic HER. AL-Pt/Pd 3 Pb exhibits an outstanding HER activity with an overpotential of only 13.8 mV at 10 mA/cm 2 and a high mass activity of 7834 A/g Pd+Pt at -0.05 V, both largely surpassing those of commercial Pt/C (30 mV, 1486 A/g Pt ). In addition, AL-Pt/Pd 3 Pb shows excellent stability and robustness. Theoretical calculations show that the improved activity is mainly derived from the charge transfer from Pd 3 Pb to Pt, resulting in a strong electrostatic interaction that can stabilize the transition state and lower the barrier.

The prominent size effect of metal nanoparticles shapes decisively nanocatalysis, but entanglement of the corresponding geometric and electronic effects prevents exploiting their distinct functionalities. In this work, we demonstrate that in palladium (Pd)-catalyzed aerobic oxidation of benzyl alcohol, the geometric and electronic effects interplay and compete so intensively that both activity and selectivity showed in volcano trends on the Pd particle size unprecedentedly. By developing a strategy of site-selective blocking via atomic layer deposition along with first principles calculations, we disentangle these two effects and unveil that the geometric effect dominates the right side of the volcano with larger-size Pd particles, whereas the electronic effect directs the left of the volcano with smaller-size Pd particles substantially. Selective blocking of the low-coordination sites prevents formation of the undesired by-product beyond the volcano relationship, achieving a remarkable benzaldehyde selectivity and activity at the same time for 4-nm Pd. Disentangling the geometric and electronic effects of metal nanoparticles opens a new dimension for rational design of catalysts.

Oxygen electrocatalysis plays a critical role in the efficiency of important energy conversion and storage systems. While many efforts have focused on designing efficient electrocatalysts for these processes, optimal catalysts that are inexpensive, active, selective, and stable are still being searched. Nonstoichiometric, mixed-metal oxides present a promising group of electrocatalysts for these processes due to the versatility of the surface composition and fast oxygen conducting properties. Herein, we demonstrate, using a combination of theoretical and experimental studies, the ability to develop design principles that can be used to engineer oxygen electrocatalysis activity of layered, mixed ionic-electronic conducting Ruddlesden-Popper (R-P) oxides. We show that a density function theory (DFT) derived descriptor, O 2 binding energy on a surface oxygen vacancy, can be effective in identifying efficient R-P oxide structures for oxygen reduction reaction (ORR). Using a controlled synthesis method, well-defined nanostructures of R-P oxides are obtained, which along with thermochemical and electrochemical activity studies are used to validate the design principles. This has led to the identification of a highly active ORR electrocatalyst, nanostructured Co-doped lanthanum nickelate oxide, which when incorporated in solid oxide fuel cell cathodes significantly enhances the performance at intermediate temperatures (∼550 °C), while maintaining long-term stability. The reported findings demonstrate the effectiveness of the developed design principles to engineer mixed ionic-electronic conducting oxides for efficient oxygen electrocatalysis, and the potential of nanostructured Co-doped lanthanum nickelate oxides as promising catalysts for oxygen electrocatalysis.

Herein, a series of lasiokaurin derivatives were designed and synthesized. All the derivatives together with lasiokaurin and oridonin were tested for their antimicrobial and antiproliferative activity. Compound 16 showed the most promising antimicrobial activity with MICs of 2.0 and 1.0 μg/mL against Gram-Positive bacteria S. aureus and B. subtilis, respectively. All the synthetic lasiokaurin derivatives showed better antiproliferative activity than parent compound lasiokaurin 1. Compound 10 exhibited the strongest cytotoxicity with IC 50 values of 0.47 and 0.20 μM against MGC-803 and CaEs-17 cells, accordingly. Moreover, it was shown to have potent antitumor activity in vivo in a murine model of MGC-803 gastric cancer. Preliminary SARs were also concluded based on obtained data. The apoptosis-inducing effects of 10 were further investigated using CaEs-17 cells. The results showed that lasiokaurin derivative 10 could induce apoptosis via mitochondria related pathway and arrest CaEs-17 cell cycle at S phase. Compound 10 could also affect apoptosis-related proteins that was up-regulation of CDK2 and down-regulation of ATM and cyclin A1.

Background: Antiphospholipid syndrome (APS)-related immune factors are considered as an important cause of recurrent spontaneous abortion (RSA). Anticoagulant and anti-inflammatory treatments are believed to effectively improve adverse pregnancy outcomes by affecting the abnormal autoimmune response of the maternal-fetal interface. The aim of this study was to observe the clinical characteristics and treatment outcomes of anticoagulant regimens and anti-inflammatory plus anticoagulation regimens for APS-related RSA., Methods: APS-related RSA cases from September 2011 to September 2016 at Peking University Third Hospital were retrospectively analyzed. The patients were assigned to study group (anti-inflammation plus anticoagulation) and control group (simple anticoagulation). The incidence of repeat abortion, the incidence of placental dysfunction, the gestational weeks of pregnancy, and the mean weight of the fetus were observed., Results: The pregnancy and neonatal outcome indicators of the repeat pregnancy loss rate (11.11% vs. 22.70%), placental dysfunction-related diseases (6.35% vs. 15.60%), the mean birth weight of infants born after 24 weeks gestation (3152.41 ± 844.67 g vs. 2765.76 ± 816.40 g), full-term delivery weight (3456.28 ± 419.79 g vs. 3076.18 ± 518.79 g), the proportions of low birth weight infants (12.70% vs. 21.98%), and small for gestational age (6.35% vs. 14.18%) differed significantly between the study and control groups (all P< 0.05). The incidence of preterm delivery, term delivery, and stillbirth was not significantly different between the two groups, and there was no significant difference between the study and control groups in gestational age at birth (37.6 ± 3.3 weeks vs. 36.9 ± 3.2 weeks; P > 0.05)., Conclusion: The anti-inflammatory and anticoagulation regimen is more effective than the simple anticoagulation regimen in the treatment of APS recurrent abortion.

Proliferation, a key feature of cancer cells, accounts for the majority of cancer-related diseases resulting in mortality. MicroRNAs (miRNAs) plays important post-transcriptional modulation roles by acting on multiple signaling pathways, but the underlying mechanism in proliferation and tumorigenicity is unclear. Here, we identified the role of miR-150 in proliferation and tumorigenicity in leukemia stem cells (LSCs; CD34+CD38- cells). miR-150 expression was significantly down-regulated in LSCs from leukemia cell lines and clinical samples. Functional assays demonstrated that increased miR-150 expression inhibited proliferation and clonal and clonogenic growth, enhanced chemosensitivity, and attenuated tumorigenic activity of LSCs in vitro . Transplantation animal studies revealed that miR-150 overexpression progressively abrogates tumor growth. Immunohistochemistry assays demonstrated that miR-150 overexpression enhanced caspase-3 level and reduced Ki-67 level. Moreover, luciferase reporter assays indicated Nanog is a direct and functional target of miR-150. Nanog silencing using small interfering RNA recapitulated anti-proliferation and tumorigenicity inhibition effects. Furthermore, miR-150 directly down-regulated the expression of other cancer stem cell factors including Notch2 and CTNNB1. These results provide insights into the specific biological behavior of miR-150 in regulating LSC proliferation and tumorigenicity. Targeting this miR-150/Nanog axis would be a helpful therapeutic strategy to treat acute myeloid leukemia.

Calixarene-based compounds are highly effective therapeutic agents against cancer. This study aims to prepare a series of calix [n]arene (n = 4, 6, 8) polyhydroxyamine derivatives (3a-3m) and to study their potential antitumor activities. The single crystal structure of calixs[4]arene derivative 3a was determined through X-ray diffraction. We assessed the ability of the prepared calix [n]arene polyhydroxyamine derivatives to induce cytotoxicity in six cancer cell lines by performing cancer cell growth inhibition assays. Results demonstrated that compounds 3a-3d achieved IC50 values ranging from 1.6 μM to 11.3 μM. Among the different compounds, 3a and 3b exerted the strongest cytotoxic effect in inhibiting the growth of SKOV3 cells. In relation to the underlying mechanisms of cytotoxic effects, cell cycle analysis revealed that the exposure of SKOV3 cells to 3a induced cell cycle arrest in the G0/G1 phase, suggesting a reduction in DNA synthesis. Immunofluorescent staining indicated that the protein expression levels of caspase-3 and p53 in cells significantly increased, whereas that of Bcl-2 was effectively suppressed. Meanwhile, no significant changes in Bax were observed in SKOV3 cells. These results highlight that calixarene 3a can be further studied as a potential anticancer agent., (Copyright © 2016 Elsevier Masson SAS. All rights reserved.)

Atomic layer deposition (ALD) of alumina using trimethylaluminum (TMA) has technological importance in microelectronics. This process has demonstrated a high potential in applications of protective coatings on Cu surfaces for control of diffusion of Cu in Cu2S films in photovoltaic devices and sintering of Cu-based nanoparticles in liquid phase hydrogenation reactions. With this motivation in mind, the reaction between TMA and oxygen was investigated on Cu(111) and Cu2O/Cu(111) surfaces. TMA did not adsorb on the Cu(111) surface, a result consistent with density functional theory (DFT) calculations predicting that TMA adsorption and decomposition are thermodynamically unfavorable on pure Cu(111). On the other hand, TMA readily adsorbed on the Cu2O/Cu(111) surface at 473 K resulting in the reduction of some surface Cu(1+) to metallic copper (Cu(0)) and the formation of a copper aluminate, most likely CuAlO2. The reaction is limited by the amount of surface oxygen. After the first TMA half-cycle on Cu2O/Cu(111), two-dimensional (2D) islands of the aluminate were observed on the surface by scanning tunneling microscopy (STM). According to DFT calculations, TMA decomposed completely on Cu2O/Cu(111). High-resolution electron energy loss spectroscopy (HREELS) was used to distinguish between tetrahedrally (Altet) and octahedrally (Aloct) coordinated Al(3+) in surface adlayers. TMA dosing produced an aluminum oxide film, which contained more octahedrally coordinated Al(3+) (Altet/Aloct HREELS peak area ratio ≈ 0.3) than did dosing O2 (Altet/Aloct HREELS peak area ratio ≈ 0.5). After the first ALD cycle, TMA reacted with both Cu2O and aluminum oxide surfaces in the absence of hydroxyl groups until film closure by the fourth ALD cycle. Then, TMA continued to react with surface Al-O, forming stoichiometric Al2O3. O2 half-cycles at 623 K were more effective for carbon removal than O2 half-cycles at 473 K or water half-cycles at 623 K. The growth rate was approximately 3-4 Å/cycle for TMA+O2 ALD (O2 half-cycles at 623 K). No preferential growth of Al2O3 on the steps of Cu(111) was observed. According to STM, Al2O3 grows homogeneously on Cu(111) terraces.

The terraces, edges, and facets of nanoparticles are all active sites for heterogeneous catalysis. These different active sites may cause the formation of various products during the catalytic reaction. Here we report that the step sites of Pd nanoparticles (NPs) can be covered precisely by the atomic layer deposition (ALD) method, whereas the terrace sites remain as active component for the hydrogenation of furfural. Increasing the thickness of the ALD-generated overcoats restricts the adsorption of furfural onto the step sites of Pd NPs and increases the selectivity to furan. Furan selectivities and furfural conversions are linearly correlated for samples with or without an overcoating, though the slopes differ. The ALD technique can tune the selectivity of furfural hydrogenation over Pd NPs and has improved our understanding of the reaction mechanism. The above conclusions are further supported by density functional theory (DFT) calculations., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The selective oxidation of propylene with O2 to propylene oxide and acrolein is of great interest and importance. We report the crystal-plane-controlled selectivity of uniform capping-ligand-free Cu2 O octahedra, cubes, and rhombic dodecahedra in catalyzing propylene oxidation with O2 : Cu2 O octahedra exposing {111} crystal planes are most selective for acrolein; Cu2 O cubes exposing {100} crystal planes are most selective for CO2 ; Cu2 O rhombic dodecahedra exposing {110} crystal planes are most selective for propylene oxide. One-coordinated Cu on Cu2 O(111), three-coordinated O on Cu2 O(110), and two-coordinated O on Cu2 O(100) were identified as the catalytically active sites for the production of acrolein, propylene oxide, and CO2 , respectively. These results reveal that crystal-plane engineering of oxide catalysts could be a useful strategy for developing selective catalysts and for gaining fundamental understanding of complex heterogeneous catalytic reactions at the molecular level., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The catalytic role of the Pt--Fe cation ensemble presented at the perimeters of the FeO film supported on Pt(111) for low-temperature CO oxidation and the promotion of water on activity were studied by using DFT calculations. We found that the perimeter sites along the edge of the FeO islands on Pt provided a favorable ensemble that consisted of coordinatively unsaturated ferrous species and nearby Pt atoms for O(2) and H(2) O activation free from CO poison. A dissociative oxygen atom at the Pt--Fe cation ensemble reacts easily with CO adsorbed on nearby Pt. The OH group from water dissociation not only facilitates activation of the oxygen molecule, more importantly it opens a facile reaction channel for CO oxidation through the formation of the carboxyl intermediate. The presence of the OH group on the FeO film strengthens interfacial interactions between FeO and Pt(111), which would make the FeO film more resistant to further oxidation. The importance of the Pt--Fe cation ensemble and the role of water as a cocatalyst for low-temperature CO oxidation is highlighted., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Purpose: The dart-throwing motion is an important movement pattern during most wrist actions. The aim of this study was to investigate length changes in the wrist ligaments in different positions of the dart-throw motion in vivo., Methods: We obtained computed tomography scans of the wrists of 6 volunteers at 5 positions of the wrist during the dart-throw motion: 20° of radial deviation with 60° of extension; 10° of radial deviation with 30° of extension; the neutral position of the carpus; 20° of ulnar deviation with 30° of flexion; and 40° of ulnar deviation with 60° of flexion. We reconstructed the 3-dimensional carpal and distal radioulnar joint structures with customized software and computed changes in length of 8 palmar and dorsal wrist ligaments., Results: From wrist radial deviation with extension to ulnar deviation with flexion, the radioscaphocapitate, long radiolunate, ulnocapitate, and ulnotriquetral ligaments decreased significantly in length but the dorsal radiocarpal ligament and the dorsal intercarpal (DIC) ligament inserting on the trapezoid lengthened significantly; the ulnolunate ligament and the DIC ligament inserting on the scaphoid were shortest in neutral position., Conclusions: At wrist radial extension, the radioscaphocapitate, long radiolunate, ulnocapitate, and ulnotriquetral ligaments are lengthened and under increased tension. At wrist ulnar flexion, the dorsal radiocarpal ligament and the DIC ligament inserting on the trapezoid are lengthened and under increased tension. The ulnolunate ligament and the DIC ligament inserting on the scaphoid are the shortest and under the least tension in neutral position. These findings will help us understand the biomechanics of the carpus during the dart-throwing motion., (Copyright © 2011 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.)

Coordinatively unsaturated ferrous (CUF) sites confined in nanosized matrices are active centers in a wide range of enzyme and homogeneous catalytic reactions. Preparation of the analogous active sites at supported catalysts is of great importance in heterogeneous catalysis but remains a challenge. On the basis of surface science measurements and density functional calculations, we show that the interface confinement effect can be used to stabilize the CUF sites by taking advantage of strong adhesion between ferrous oxides and metal substrates. The interface-confined CUF sites together with the metal supports are active for dioxygen activation, producing reactive dissociated oxygen atoms. We show that the structural ensemble was highly efficient for carbon monoxide oxidation at low temperature under typical operating conditions of a proton-exchange membrane fuel cell.