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The importance of catalysts today as workhorses in most modern industrial fields cannot be downplayed. As a result, rational design and engineering of targeted catalysts have emerged as key objectives and are dependent on in-depth understanding of complex catalytic dynamics. Synchrotron radiation (SR) light sources with rich advanced experimental methods are being recognized as a comprehensive characterization platform, which can draw a full picture on such multiparameter-involved catalysis under actual working conditions. Herein, the recent progress of catalytic dynamics process studied by the means of various SR techniques is summarized. In particular, SR-based spectroscopic, scattering, and imaging investigations on true catalysts are first introduced with the potential of in situ and operando characterizations. Apparently, the limitations from single SR technique naturally prompt a simple combination of SR techniques to better understand the whole catalysis process. Moreover, the discrepancies among various online testing facilities and batches of samples, along with random/systematic errors introduced by traditional intermittent/asynchronous measurement make it imperative to develop more prolific systems, complementary of multiple SR techniques for deep probing of dynamic catalytic processes. It is believed that the booming new light sources can further enrich the current multiple SR techniques, and thus may realize the true visualization on future catalytic dynamic processes., (© 2023 Wiley-VCH GmbH.)

Background: Tsetse flies are vectors of the genus Trypanosoma that cause African trypanosomiasis, a serious parasitic disease of people and animals. Reliable data on the vector distribution and the trypanosome species they carry is pertinent for planning sustainable control strategies. This study was carried out to estimate the spatial distribution, apparent density, and trypanosome infection rates of tsetse flies in two districts that fall within a vector genetic transition zone in northern Uganda., Materials and Methods: Capturing of tsetse flies was done using biconical traps deployed in eight villages in Oyam and Otuke, two districts that fall within the vector genetic transition zone in northern Uganda. Trapped tsetse flies were sexed and morphologically identified to species level and subsequently analyzed for detection of trypanosome DNA. Trypanosome DNA was detected using a nested PCR protocol based on primers amplifying the internal transcribed spacer (ITS) region of ribosomal DNA., Results: A total of 717 flies (406 females; 311 males) were caught, all belonging to the Glossina fuscipes fuscipes species. The overall average flies/trap/day (FTD) was 2.20 ± 0.3527 (mean ± SE). Out of the 477 (201 male; 276 females) flies analyzed, 7.13% (34/477) were positive for one or more trypanosome species. Three species of bovine trypanosomes were detected, namely, Trypanosoma vivax , 61.76% (21/34), T. congolense , 26.47% (9/34), and T. brucei brucei , 5.88% (2/34), and two cases of mixed infection of T. congolense and T. brucei brucei , 5.88% (2/34). The infection rate was not significantly associated with the sex of the fly (generalized linear model (GLM), χ 2 = 0.051, p = 0.821, df = 1, n = 477) and district of origin ( χ 2 = 0.611, p = 0.434, df = 1, n = 477). However, trypanosome infection was highly significantly associated with the fly's age based on wing fray category ( χ 2 = 7.56, p = 0.006, df = 1, n = 477), being higher among the very old than the young., Conclusion: The relatively high tsetse density and trypanosome infection rate indicate that the transition zone is a high-risk area for perpetuating animal trypanosomiasis. Therefore, appropriate mitigation measures should be instituted targeting tsetse and other biting flies that may play a role as disease vectors, given the predominance of T. vivax in the tsetse samples., Competing Interests: The authors declare that they have no competing interests., (Copyright © 2022 Robert Opiro et al.)

Broadly, the oxygen evolution reaction (OER) has been deeply understood as a significant part of energy conversion and storage. Nevertheless, the anions in the OER catalysts have been neglected for various reasons such as inactive sites, dissolution, and oxidation, amongst others. Herein, we applied a model catalyst s-Ni(OH) 2 to track the anionic behavior in the catalyst during the electrochemical process to fill this gap. The advanced operando synchrotron radiation Fourier transform infrared (SR-FTIR) spectroscopy, synchrotron radiation photoelectron spectroscopy (SRPES) depth detection and differential X-ray absorption fine structure (Δ-XAFS) spectrum jointly point out that some oxidized sulfur species (SO 4 2- ) will self-optimize new Ni-S bonds during OER process. Such amazing anionic self-optimization (ASO) behavior has never been observed in the OER process. Subsequently, the optimization-derived component shows a significantly improved electrocatalytic performance (activity, stability, etc.) compared to reference catalyst Ni(OH) 2 . Theoretical calculation further suggests that the ASO process indeed derives a thermodynamically stable structure of the OER catalyst, and then gives its superb catalytic performance by optimizing the thermodynamic and kinetic processes in the OER, respectively. This work demonstrates the vital role of anions in the electrochemical process, which will open up new perspectives for understanding OER and provide some new ideas in related fields (especially catalysis and chemistry)., Competing Interests: Conflict of interest The authors declare that they have no conflict of interest., (Copyright © 2020 Science China Press. Published by Elsevier B.V. All rights reserved.)

Despite recent advances in controlling ice formation and growth, it remains a challenge to design anti-icing materials in various fields from atmospheric to biological cryopreservation. Herein, tungsten diselenide (WSe 2 )-polyvinyl pyrrolidone (PVP) nanoparticles (NPs) are synthesized through one-step solvothermal route. The WSe 2 -PVP NPs show synergetic ice regulation ability both in the freezing and thawing processes. Molecularly speaking, PVP containing amides group can form hydrogen bonds with water molecules. At a macro level, the WSe 2 -PVP NPs show adsorption-inhibition and photothermal conversation effects to synergistically restrict ice growth. Meanwhile, WSe 2 -PVP NPs are for the first time used for the cryopreservation of human umbilical vein endothelial cell (HUVEC)-laden constructs based on rapid freezing with low concentrations of cryoprotectants (CPAs), the experimental results indicate that a minimal concentration (0.5 mg mL -1 ) of WSe 2 -PVP NPs can increase the viabilities of HUVECs in the constructs post cryopreservation (from 55.8% to 83.4%) and the cryopreserved constructs can also keep good condition in vivo within 7 days. Therefore, this work provides a novel strategy to synergistically suppress the formation and growth of the ice crystalsfor the cryopreservation of cells, tissues, or organs., Competing Interests: The authors declare no conflict of interest., (© 2021 The Authors. Published by Wiley‐VCH GmbH.)

Molybdenum disulfide (MoS 2 ) has attracted much attention as a promising alternative to Pt-based catalysts for highly efficient hydrogen generation. However, it suffers sluggish kinetics for driving the hydrogen evolution reaction (HER) process because of inert basal planes, especially in alkaline solution. Here, we show a combination of heteroatom doping and phase transformation strategies to engineer the in-plane structure of MoS 2 , that trigger their catalytic activities. Systematic characterizations are performed with advanced aberration-corrected microscopy and X-ray techniques, indicating that an as-designed MoS 2 catalyst has a distorted zigzag-chain superlattice in metallic phase, while its in-plane structure was engineered via the incorporation of cobalt and oxygen species. The optimal Co, O dual-doped metallic phase molybdenum disulfide (1T-MoS 2 ) electrocatalyst shows a significantly enhanced HER activity with a low overpotential of 113 mV at 10 mA cm -2 and corresponding small Tafel slope of 50 mV dec -1 , accompanied by the robust stability in alkaline media. The calculated turnover frequency is higher than 6.65 H 2 s -1 at an overpotential of 200 mV. More in-depth insights from the first-principle calculations illustrate that the water dissociation as a rate-determining step was largely accelerated by the in-plane Co-O-Mo species and fast electron transfer of the catalyst. Benefiting from ingenious design and fine identifications, this work provides a fundamental understanding of the relationships among heteroatom doping, phase transformation, and performance for MoS 2 -based catalysts.