Spin-Magnetic Effect of d-π Conjugation Polymer Enhanced O-H Cleavage in Water Oxidation.

A deep understanding of the mechanism for the spin-magnetic effect on O-H cleavage is crucial for the development of new catalysts for water oxidation. Herein, we designed and synthesized the crystalline Fe-DABDT and Co-DABDT (DABDT = 2,5-diaminobenzene-1,4-dithiol) and optimized an effective magnetic moment to explore the role of the spin-magnetic effect in the regulation of water oxidation activity. It can be found that the OER activity of the catalyst is positively correlated with its effective magnetic moment. Under the external magnetic field, Fe-DABDT with more spin single electrons has a stronger spin-magnetic response to water oxidation than Fe/Co-DABDT and Co-DABDT. The increase in OER current of Fe-DABDT is nearly 2 times higher than that of Co-DABDT. Experimental and density functional theory studies show that magnetized Fe sites could realize nucleophilic reaction, accelerate the polarization of electron spin states, and promote the polar decomposition of O-H and the formation of the O-O bond. This study provides mechanistic insight into the spin-magnetic effect of oxygen evolution reaction and further understanding of the spin origin of catalytic activity, which is expected to improve the energy efficiency of hydrogen production.

Highly Ordered Hierarchical Macro-Mesoporous Carbon-Supported Cobalt Electrocatalyst for Efficient Oxygen Evolution Reaction.

Metal-organic frameworks (MOFs) and their derivatives have been extensively employed in Oxygen Evolution Reaction (OER) catalysts due to their significantly larger specific surface areas, distinct metal centers, and well-organized porous structures. However, the microporous structure of MOFs and their derivatives presents mass transfer resistance, limiting their further development. Drawing inspiration from hierarchical structures allowing for the transport and exchange of substances in the biological world, we designed and fabricated biomimetic layered porous structures within ZIF-67 and its derivatives. Based on this, we achieved a three-dimensional ordered layered porous nitrogen-doped carbon-coated magnetic cobalt catalyst (3DOLP Co@NDC) with a biomimetic pore structure. It is found that the 3DOLP Co@NDC (352 mV @10 mA cm-1) was better than Co@NDC (391 mV @10 mA cm-1). The introduction of a three-dimensional ordered layered porous structure is conducive to increasing the specific surface area of the material, increasing the electrochemical active area, and improving the catalytic performance of the material. The introduction of a three-dimensional ordered layered porous structure would help to build a bionic grade pore structure. The existence of biomimetic grade pore structure can effectively reduce the mass transfer resistance, improve the material exchange efficiency, and accelerate the reaction kinetics.

Prediction of drug permeation through microneedled skin by machine learning.

Stratum corneum is the outermost layer of the skin preventing external substances from entering human body. Microneedles (MNs) are sharp protrusions of a few hundred microns in length, which can penetrate the stratum corneum to facilitate drug permeation through skin. To determine the amount of drug delivered through skin, in vitro drug permeation testing is commonly used, but the testing is costly and time-consuming. To address this issue, machine learning methods were employed to predict drug permeation through the skin, circumventing the need of conducting skin permeation experiments. By comparing the experimental data and simulated results, it was found extreme gradient boosting (XGBoost) was the best among the four simulation methods. It was also found that drug loading, permeation time, and MN surface area were critical parameters in the models. In conclusion, machine learning is useful to predict drug permeation profiles for MN-facilitated transdermal drug delivery.

TNF signaling pathway-mediated microglial activation in the PFC underlies acute paradoxical sleep deprivation-induced anxiety-like behaviors in mice.

Acute sleep deprivation is a common condition in modern life and increases anxiety symptoms in healthy individuals. The neuroinflammatory response induced by microglial activation could be an important contributing factor, but its underlying molecular mechanisms are still unclear. In the present study, we first found that acute paradoxical sleep deprivation (PSD) induced by the modified multiple platform method (MMPM) for 6 h led to anxiety-like behavior in mice, as verified by the open field test, elevated plus maze test, light-dark box test, and marble burying test. In addition, bioinformatic analysis suggested an important relationship between acute sleep deprivation and brain inflammatory signaling pathways. Key genes enriched in the TNF signaling pathway were confirmed to be altered during acute PSD by qPCR and Western blot analyses, including the upregulation of the prostaglandin-endoperoxide synthase 2 (Ptgs2) and suppressor of cytokine signaling 3 protein (Socs3) genes and the downregulation of the cysteine-aspartic acid protease 3 (Casp3) gene. Furthermore, we found that microglial cells in the prefrontal cortex (PFC) were activated with significant branch structure changes and that the cell body area was increased in the PSD model. Finally, we found that minocycline, a tetracycline with anti-inflammatory properties, may ameliorate the anxiogenic effect and microglial activation. Our study reveals significant correlations of anxiety-like behavior, microglial activation, and inflammation during acute PSD.

Revealing two dynamic dengue epidemic clusters in Thailand.

BACKGROUND: Thailand is home to around 69 million individuals. Dengue is hyper-endemic and all 4 serotypes are in active circulation in the country. Dengue outbreaks occur almost annually within Thailand in at least one province but the spatio-temporal and environmental interface of these outbreaks has not been studied. METHODS: We develop Bayesian regime switching (BRS) models to characterize outbreaks, their persistence and infer their likelihood of occurrence across time for each administrative province where dengue case counts are collected. BRS was compared against two other classification tools and their agreement is assessed. We further examine how these spatio-temporal clusters of outbreak clusters arise by comparing reported dengue case counts, urban population, urban land cover, climate and flight volumes on the province level. RESULTS: Two dynamic dengue epidemic clusters were found nationally. One cluster consists of 47 provinces and is highly outbreak prone. Provinces with a large number of case counts, urban population, urban land cover and incoming flight passengers are associated to the epidemic prone cluster of dengue. Climate has an effect on determining the probability of outbreaks over time within provinces, but have less influence on whether provinces belong to the epidemic prone cluster. BRS found high agreement with other classification tools. CONCLUSIONS: Importation and urbanization drives the risk of outbreaks across regions strongly. In provinces estimated to have high epidemic persistence, more resource allocation to vector control should be applied to those localities as heightened transmission counts are likely to occur over a longer period of time. Clustering of epidemic and non-epidemic prone areas also highlights the need for prioritization of resource allocation for disease mitigation over provinces in Thailand.

Time varying methods to infer extremes in dengue transmission dynamics.

Dengue is an arbovirus affecting global populations. Frequent outbreaks occur, especially in equatorial cities such as Singapore, where year-round tropical climate, large daily influx of travelers and population density provide the ideal conditions for dengue to transmit. Little work has, however, quantified the peaks of dengue outbreaks, when health systems are likely to be most stretched. Nor have methods been developed to infer differences in exogenous factors which lead to the rise and fall of dengue case counts across extreme and non-extreme periods. In this paper, we developed time varying extreme mixture (tvEM) methods to account for the temporal dependence of dengue case counts across extreme and non-extreme periods. This approach permits inference of differences in climatic forcing across non-extreme and extreme periods of dengue case counts, quantification of their temporal dependence as well as estimation of thresholds with associated uncertainties to determine dengue case count extremities. Using tvEM, we found no evidence that weather affects dengue case counts in the near term for non-extreme periods, but that it has non-linear and mixed signals in influencing dengue through tvEM parameters in the extreme periods. Using the most appropriate tvEM specification, we found that a threshold at the 70th (95% credible interval 41.1, 83.8) quantile is optimal, with extreme events of 526.6, 1052.2 and 1183.6 weekly case counts expected at return periods of 5, 50 and 75 years. Weather parameters at a 1% scaled increase was found to decrease the long-run expected case counts, but larger increases would lead to a drastic expected rise from the baseline correspondingly. The tvEM approach can provide valuable inference on the extremes of time series, which in the case of infectious disease notifications, allows public health officials to understand the likely scale of outbreaks in the long run.

[Surgical treatment of tibia plateau fractures with external fixator and the locking plate].

OBJECTIVE: To observe the clinical effect of the treatment for complex fractures of the tibial plateau through the application of the external fixator and the locking plate. METHODS: From Feb. 2006 to Oct. 2008,12 patients with tibial plateau fractures were treated with external fixator and locking plate included 8 males and 4 females with an average age of 38 years ranging from 23 to 59. According to Schatzker type, 7 cases were type V and 5 cases were type VI. Using an anteromedial incision and an anterolateral approach, the locking plate were fixed in the tibia lateral. The collapse and height lossing of tibial plateau was observed through X-ray film before and after operation. The function of knee joint was evaluated according to HSS scoring. RESULTS: These patients were followed up for 4 to 18 months (means 9.79 months). Eleven cases had bone primary union,and 1 delayed union. No deep phlebothrombosis and osteofascial compartment syndrome occurened. The average healing time was 3.1 months. Between the preoperative and postoperative X-ray film there were no second stage depression fracture of the tibial plateau,postoperative reduction loss and bad alignment. The range of knee flexion was 90 degrees to 110 degrees. The HSS knee functional scoring was(75.50 +/- 10.01)scores after operation and (21.50 +/- 11.68) scores before operation. CONCLUSION: The treatment with the external fixator and the locking plate for complex fractures of the tibial plateau could provid continuous stability of fixation,prevent the fracture from second stage displacement and the knee force line change, protect the soft-tissue around the knee, reduce the postoperative complications. The knee joint function is satisfied.