The efficiency of splitting water into hydrogen and oxygen is highly dependent on the catalyst used. Herein, ultrathin Ni(0)‐embedded Ni(OH)2 heterostructured nanosheets, referred to as Ni/Ni(OH)2 ...nanosheets, with superior water splitting activity are synthesized by a partial reduction strategy. This synthetic strategy confers the heterostructured Ni/Ni(OH)2 nanosheets with abundant Ni(0)‐Ni(II) active interfaces for hydrogen evolution reaction (HER) and Ni(II) defects as transitional active sites for oxygen evolution reaction (OER). The obtained Ni/Ni(OH)2 nanosheets exhibit noble metal‐like electrocatalytic activities toward overall water splitting in alkaline condition, to offer 10 mA cm−2 in HER and OER, the required overpotentials are only 77 and 270 mV, respectively. Based on such an outstanding activity, a water splitting electrolysis cell using the Ni/Ni(OH)2 nanosheets as the cathode and anode electrocatalysts has been successfully built. When the output voltage of the electrolytic cell is 1.59 V, a current density of 10 mA cm−2 can be obtained. Moreover, the durability of Ni/Ni(OH)2 nanosheets in the alkaline electrolyte is much better than that of noble metals. No obvious performance decay is observed after 20 h of catalysis. This facile strategy paves the way for designing highly active non‐precious‐metal catalyst to generate both hydrogen and oxygen by electrolyzing water at room temperature.
Heterostructured Ni/Ni(OH)2 nanosheets synthesized using a partial reduction strategy are used as an efficient multifunctional electrocatalyst for the hydrogen evolution reaction, the oxygen evolution reaction, and overall water splitting. This work opens up new opportunities in the rational design of cost‐effective and highly efficient multifunctional electrocatalysts for renewable energy conversion.
The global demand for lactic acid (LA) is increasing due to its successful application as monomer for the manufacture of bioplastics. Although N‐heterocyclic carbene (NHC) iridium complexes are ...promising molecular catalysts for LA synthesis, their instabilities have hindered their utilization especially in commercial applications. Here, we report that a porous self‐supported NHC‐iridium coordination polymer can efficiently prevent the clusterization of corresponding NHC‐Ir molecules and can function as a solid molecular recyclable catalyst for dehydrogenation of bio‐polyols to form LA with excellent activity (97 %) and selectivity (>99 %). A turnover number of up to 5700 could be achieved in a single batch, due to the synergistic participation of the Ba2+ and hydroxide ions, as well as the blockage of unwanted pathways by adding methanol. Our findings demonstrate a potential route for the industrial production of LA from cheap and abundant bio‐polyols, including sorbitol.
Bio‐polyols conversion: A series of 3D porous self‐supported NHC‐iridium coordination polymers were prepared and could function as recyclable solid molecular catalysts for dehydrogenation of bio‐polyols to lactic acid with excellent activity and selectivity due to the synergistic participation of the Ba2+ and hydroxide ions, as well as the blockage of unwanted pathways by adding methanol.
Ligands in ligand-protected metal clusters play a crucial role, not only because of their interaction with the metal core, but also because of the functionality they provide to the cluster. Here, we ...report the utilization of secondary phosphine oxide (SPO), as a new family of functional ligands, for the preparation of an undecagold cluster Au11-SPO. Different from the commonly used phosphine ligand (i.e., triphenylphosphine, TPP), the SPOs in Au11-SPO work as electron-withdrawing anionic ligands. While coordinating to gold via the phosphorus atom, the SPO ligand keeps its O atom available to act as a nucleophile. Upon photoexcitation, the clusters are found to inject holes into p-type semiconductors (here, bismuth oxide is used as a model), sensitizing the p-type semiconductor in a different way compared to the photosensitization of a n-type semiconductor. Furthermore, the Au11-SPO/Bi2O3 photocathode exhibits a much higher activity toward the hydrogenation of benzaldehyde than a TPP-protected Au11-sensitized Bi2O3 photocathode. Control experiments and density functional theory studies point to the crucial role of the cooperation between gold and the SPO ligands on the selectivity toward the hydrogenation of the CO group in benzaldehyde.
Aberrant topological organization of whole-brain networks has been inconsistently reported in studies of patients with major depressive disorder (MDD), reflecting limited sample sizes. To address ...this issue, we utilized a big data sample of MDD patients from the REST-meta-MDD Project, including 821 MDD patients and 765 normal controls (NCs) from 16 sites. Using the Dosenbach 160 node atlas, we examined whole-brain functional networks and extracted topological features (e.g., global and local efficiency, nodal efficiency, and degree) using graph theory-based methods. Linear mixed-effect models were used for group comparisons to control for site variability; robustness of results was confirmed (e.g., multiple topological parameters, different node definitions, and several head motion control strategies were applied). We found decreased global and local efficiency in patients with MDD compared to NCs. At the nodal level, patients with MDD were characterized by decreased nodal degrees in the somatomotor network (SMN), dorsal attention network (DAN) and visual network (VN) and decreased nodal efficiency in the default mode network (DMN), SMN, DAN, and VN. These topological differences were mostly driven by recurrent MDD patients, rather than first-episode drug naive (FEDN) patients with MDD. In this highly powered multisite study, we observed disrupted topological architecture of functional brain networks in MDD, suggesting both locally and globally decreased efficiency in brain networks.
Injectable thermogelated hydrogels with self‐healing and multi‐responsiveness are emerging as a class of significant “smart” materials because of their many potential applications. However, there are ...only very limited precedents that combine thermogels with self‐healing and tunable functions. In this work, it is demonstrated that N‐alkyl substituted carbamate modified polyvinyl alcohol with borax as a crosslinker enables a variety of tunable and dynamic thermogelation properties. As far as it is known, this is the first polyvinyl alcohol–based thermogel system. This system characterizes shear thinning, multiple responsiveness, and dynamic gelation features. Systematic investigation suggests that these features collaborate to contribute to attractive injectability, quick self‐healing ability, and tunable thermogelation behavior. A stepwise in situ gelation and carbon dioxide–triggered release are demonstrated.
For the first time, N‐alkyl substituted carbamate modified polyvinyl alcohol with borax as a crosslinker enables a variety of tunable and dynamic thermogelation properties, including shear thinning, multiple responsiveness, dynamic gelation features and self‐healing. This system can be practically useful in the biorelevant fields.
l-threonine dehydrogenase (Tdh) is an enzyme that links threonine metabolism to epigenetic modifications and mitochondria biogenesis. In vitro studies show that it is critical for the regulation of ...trimethylation of histone H3 lysine 4 (H3K4me3) levels and cell fate determination of mouse embryonic stem cells (mESCs). However, whether Tdh regulates a developmental process in vivo and, if it does, whether it also primarily regulates H3K4me3 levels in this process as it does in mESCs, remains elusive. Here, we revealed that, in zebrafish hematopoiesis, tdh is preferentially expressed in neutrophils. Knockout of tdh causes a decrease in neutrophil number and slightly suppresses their acute injury-induced migration, but, unlike the mESCs, the level of H3K4me3 is not evidently reduced in neutrophils sorted from the kidney marrow of adult tdh-null zebrafish. These phenotypes are dependent on the enzymatic activity of Tdh. Importantly, a soluble supplement of nutrients that are able to fuel the acetyl-CoA pool, such as pyruvate, glucose and branched-chain amino acids, is sufficient to rescue the reduction in neutrophils caused by tdh deletion. In summary, our study presents evidence for the functional requirement of Tdh-mediated threonine metabolism in a developmental process in vivo. It also provides an animal model for investigating the nutritional regulation of myelopoiesis and immune response, as well as a useful tool for high-throughput drug/nutrition screening.
Patients with treatment-resistant depression (TRD) and those with treatment-response depression (TSD) respond to antidepressants differently and previous studies have commonly reported different ...brain networks in resistant and nonresistant patients. Using the amplitude of low-frequency fluctuations (ALFF) approach, we explored ALFF values of the brain regions in TRD and TSD patients at resting state to test the hypothesis of the different brain networks in TRD and TSD patients.
Eighteen TRD patients, 17 TSD patients and 17 gender-, age-, and education-matched healthy subjects participated in the resting-state fMRI scans.
There are widespread differences in ALFF values among TRD patients, TSD patients and healthy subjects throughout the cerebellum, the visual recognition circuit (middle temporal gyrus, middle/inferior occipital gyrus and fusiform), the hate circuit (putamen), the default circuit (ACC and medial frontal gyrus) and the risk/action circuit (inferior frontal gyrus). The differences in brain circuits between the TRD and TSD patients are mainly in the cerebellum, the visual recognition circuit and the default circuit.
The affected brain circuits of TRD patients might be partly different from those of TSD patients.
► TRD and TSD respond to drugs differently and may have different brain networks. ► ALFF method could detect functional alterations in patients and controls. ► The brain networks between the TRD and TSD patients might be partly different. ► ALFF method could be a new tool for the detection of neural activity.
The global demand for lactic acid (LA) is increasing due to its successful application as monomer for the manufacture of bioplastics. Although N‐heterocyclic carbene (NHC) iridium complexes are ...promising molecular catalysts for LA synthesis, their instabilities have hindered their utilization especially in commercial applications. Here, we report that a porous self‐supported NHC‐iridium coordination polymer can efficiently prevent the clusterization of corresponding NHC‐Ir molecules and can function as a solid molecular recyclable catalyst for dehydrogenation of bio‐polyols to form LA with excellent activity (97 %) and selectivity (>99 %). A turnover number of up to 5700 could be achieved in a single batch, due to the synergistic participation of the Ba2+ and hydroxide ions, as well as the blockage of unwanted pathways by adding methanol. Our findings demonstrate a potential route for the industrial production of LA from cheap and abundant bio‐polyols, including sorbitol.
Bio‐polyols conversion: A series of 3D porous self‐supported NHC‐iridium coordination polymers were prepared and could function as recyclable solid molecular catalysts for dehydrogenation of bio‐polyols to lactic acid with excellent activity and selectivity due to the synergistic participation of the Ba2+ and hydroxide ions, as well as the blockage of unwanted pathways by adding methanol.
Aims
The aims of this study are to apply a theory‐based mechanistic model to describe the pharmacokinetics (PK) and pharmacodynamics (PD) of S‐ and R‐warfarin.
Methods
Clinical data were obtained ...from 264 patients. Total concentrations for S‐ and R‐warfarin were measured by ultra‐high performance liquid tandem mass spectrometry. Genotypes were measured using pyrosequencing. A sequential population PK parameter with data method was used to describe the international normalized ratio (INR) time course. Data were analyzed with NONMEM. Model evaluation was based on parameter plausibility and prediction‐corrected visual predictive checks.
Results
Warfarin PK was described using a one‐compartment model. CYP2C9 *1/*3 genotype had reduced clearance for S‐warfarin, but increased clearance for R‐warfarin. The in vitro parameters for the relationship between prothrombin complex activity (PCA) and INR were markedly different (A = 0.560, B = 0.386) from the theory‐based values (A = 1, B = 0). There was a small difference between healthy subjects and patients. A sigmoid Emax PD model inhibiting PCA synthesis as a function of S‐warfarin concentration predicted INR. Small R‐warfarin effects was described by competitive antagonism of S‐warfarin inhibition. Patients with VKORC1 AA and CYP4F2 CC or CT genotypes had lower C50 for S‐warfarin.
Conclusion
A theory‐based PKPD model describes warfarin concentrations and clinical response. Expected PK and PD genotype effects were confirmed. The role of predicted fat free mass with theory‐based allometric scaling of PK parameters was identified. R‐warfarin had a minor effect compared with S‐warfarin on PCA synthesis. INR is predictable from 1/PCA in vivo.
Background
Achalasia is an esophageal motility disorder with unknown etiology. Previous findings indicate that immune‐mediated inflammatory process causes inhibitory neuronal degeneration. This study ...was designed to evaluate levels of serological cytokines and chemokines in patients with achalasia.
Methods
We collected information from forty‐seven patients with achalasia who underwent peroral endoscopic myotomy. Control samples were collected from forty‐seven age‐ and sex‐matched healthy people. The concentrations of serological cytokines and chemokines were analyzed by Luminex xMAP immunoassay. Serological and clinical data were compared between groups.
Key Results
Compared with healthy controls, achalasia patients had significantly increased concentrations of eleven cytokines and chemokines, namely, TGF‐ß1 (P < .001), TGF‐ß2 (P < .001), TGF‐ß3 (P < .001), IL‐1ra (P < .001), IL‐17 (P = .005), IL‐18 (P < .001), IFN‐γ (P < .001), MIG (P < .001), PDGF‐BB (P < .001), IP‐10 (P = .003), and SCGF‐B (P < .001). Gene ontology (GO) and network functional enrichment analysis revealed regulation of signaling receptor activity and receptor‐ligand activity were the most related pathways of these cytokines and chemokines. Levels of twelve cytokines and chemokines were significantly increased in type III compared with I/II achalasia, namely, TGF‐ß2, IL‐1ra, IL‐2Ra, IL‐18, MIG, IFN‐γ, SDF‐1a, Eotaxin, PDGF‐BB, IP‐10, MCP‐1, and TRAIL.
Conclusions and Inferences
Patients with achalasia exhibited increased levels of serological cytokines and chemokines. Levels of cytokines and chemokines were significantly increased in type III than in type I/II achalasia. Cytokines and chemokines might contribute to the inflammatory development of achalasia.
The possible mechanism of the 11 cytokines and chemokines in the pathogenesis of achalasia. Both pro‐and anti‐inflammatory pathways are activated in achalasia, while proinflammatory pathways dominate in the immune imbalance. Besides, the fibroplasia accelerates the progress of the immune reaction.
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