Active Phase Research Articles

Do people with type 2 diabetes find continuous and intermittent low-energy diets for weight loss and diabetes remission acceptable?

The Manchester Intermittent versus Daily Diet App Study (MIDDAS) tested the feasibility and potential efficacy of two remotely delivered low-energy diet (LED) programmes (800 kcal/day) to support weight loss and remission of type 2 diabetes: continuous [CLED] (8 weeks of daily LED) and intermittent [ILED] (2 days of LED/week for 28 weeks). Understanding participant experiences can help us to understand the acceptability of LED programmes to people with type 2 diabetes, informing future programme development and implementation. Twenty participants (10 CLED; 10 ILED) took part in interviews conducted at the end of the active weight loss phase (CLED week 12, ILED week 28). Interviews were transcribed and analysed thematically using the template analysis approach, with an a priori focus on acceptability. Four themes are presented: prospective acceptability, intervention coherence and perceived effectiveness, opportunity costs and self-efficacy. Both remotely supported CLED and ILED interventions appeared acceptable to participants. CLED participants found the rapid initial weight loss phase comparatively easy and highly motivating but expressed more concerns around weight maintenance. ILED participants found the more gradual weight loss initially frustrating but expressed greater confidence in their longer-term adherence. The importance of continued individualised support from healthcare professionals was emphasised, and evidence of weight loss and improvement in other medical markers through monitoring via the mobile phone app was useful. Different approaches to remotely delivered LEDs appear acceptable; therefore asking patients which approach may be more acceptable to them may be a useful way to offer individualised and tailored support.

Characterization of acute-on-chronic liver diseases: A multicenter prospective cohort study.

Acute-on-chronic liver disease (AoCLD) accounts for the majority of patients hospitalized in the Department of Hepatology or Infectious Diseases. To explore the characterization of AoCLD to provide theoretical guidance for the accurate diagnosis and prognosis of AoCLD. Patients with AoCLD from the Chinese Acute-on-Chronic Liver Failure (ACLF) study cohort were included in this study. The clinical characteristics and outcomes, and the 90-d survival rate associated with each clinical type of AoCLD were analyzed, using the Kaplan-Meier method and the log-rank test. A total of 3375 patients with AoCLD were enrolled, including 1679 (49.7%) patients with liver cirrhosis acute decompensation (LC-AD), 850 (25.2%) patients with ACLF, 577 (17.1%) patients with chronic hepatitis acute exacerbation (CHAE), and 269 (8.0%) patients with liver cirrhosis active phase (LC-A). The most common cause of chronic liver disease (CLD) was HBV infection (71.4%). The most common precipitants of AoCLD was bacterial infection (22.8%). The 90-d mortality rates of each clinical subtype of AoCLD were 43.4% (232/535) for type-C ACLF, 36.0% (36/100) for type-B ACLF, 27.0% (58/215) for type-A ACLF, 9.0% (151/1679) for LC-AD, 3.0% (8/269) for LC-A, and 1.2% (7/577) for CHAE. HBV infection is the main cause of CLD, and bacterial infection is the main precipitant of AoCLD. The most common clinical type of AoCLD is LC-AD. Early diagnosis and timely intervention are needed to reduce the mortality of patients with LC-AD or ACLF.

Innovation Project ''Masculine Aroma''(Rose and Cinnamon for Maternity)

Labor is the process of opening and thinning the cervix so that the fetus can descend into the birth canal. Labor is divided into four stages, namely labor in stage 1 (opening stage), stage II (fetal expulsion), stage III (uri stage), stage IV (monitoring stage). The results of the study with the theory that rose flowers are anti-depressants so that they can make the soul calm. To reduce the intensity of pain during the active phase of normal labor primigravida is to give twenty minutes of rose effleurage aromatherapy. Rose aromatherapy is one method that can be used to reduce the cause of pain. The aroma that comes from aromatherapy works to influence a person's emotions with the limbic (through the olfactory system) and the emotional center of the brain.(Tatang, 2016)

Chitosan as Support Material for Metal-Organic Framework based Catalysts.

Turning waste into valuable products is one of the main challenges of the chemical industry. In this work, chitosan (CS), an abundant, low-cost, and non-toxic biopolymer derived from chitin, was reshaped into beads of ~3 mm. Their suitability as a support material for active phase catalyst materials was tested for a zirconium-based Metal-Organic Framework (MOF) with incorporated Pt, namely UiO-67-Pt. Its incorporation was investigated via two procedures: a one-pot synthesis (OPS) and a post-synthetic functionalization (PSF) synthesis method. Scanning electron microscopy (SEM) images show good UiO-67-Pt dispersion throughout the CS beads for the one-pot synthesized material (UiO-67-Pt-OPS@CS). However, this uniform dispersion was not observed for the post-synthetically functionalized material (UiO-67-Pt-PSF@CS). The success of the implementation of UiO-67-Pt was evaluated with ultraviolet-visible and infrared spectroscopy for both composite materials. Thermogravimetric analysis (TGA) reveals higher thermal stabilities for UiO-67-Pt-OPS@CS composite beads in comparison to pure CS beads, but not for UiO-67-Pt-PSF@CS. The study provides valuable insights into the potential of chitosan as a green, bead-shaped support material for MOFs, offering flexibility in their incorporation through different synthesis routes. It further contributes to the broader goal of the sustainable and eco-friendly design of a new generation of catalysts made from waste materials, which will be the topic of future studies.

Circadian rhythm in pro-arrhythmic activity of pulmonary vein cardiomyocytes

Abstract Introduction Cardiomyocytes in the pulmonary vein (PV) sleeves are a major source of ectopic activity driving atrial fibrillation (AF) and episodes of AF in patients are more prevalent at night. While it is known that circadian clocks within the heart regionally control 24-hour variation in pacemaking and ventricular repolarisation, the mechanisms underlying the nighttime preponderance in AF are unknown. Purpose This study addresses the hypothesis that circadian rhythms exist in the pro-arrhythmic activity of PV cardiomyocytes. Methods Male Wistar rats maintained in a 24-hour cycle of 12-hr light/dark (lights-on at Zeitgeber time, ZT=0; lights-off, ZT12) were subject to terminal general anaesthesia (140 mg/kg Na pentobarbital i.p.) at ZT=0, 6, 12 or 18 hr and the hearts removed. RNA was extracted from left atrial (LA) appendage (LAA) and proximal PV at the LA/PV junction (3 rats per ZT) and RNA sequencing conducted. Reads were mapped to the rat genome, counts normalised and models in which ZT was or was not included as a factor compared (Likelihood Ratio Test, adjusted-P<0.01). Whole-cell current clamp recordings were made from cardiomyocytes isolated from the proximal PV (n=308) and the LAA (n=264) (N=74 rats). The effects of noradrenaline (NA, 1 µM) and acetylcholine (ACh, 1 µM) were examined. Data were plotted against the ZT of the time of recording and fitted to a sine wave to establish circadian rhythmicity (P<0.05, extra-sum-of-squares F-test). The effect of ≥24 hr constant dark in the period immediately before experiment was examined. Data are reported as mean ± standard error. Results The expression of 1368 genes varied significantly with ZT, including circadian clock components (e.g. Bmal1, Per1). PV cells were larger than LAA cells (73±1.6 pF vs 53±1.3 pF, P<0.0001) and had more depolarised resting membrane potential (-69±0.2 mV vs -72±0.1 mV, P<0.0001). Both cell types showed circadian variation in action potential duration at 90% repolarisation (APD90) and frequency of pro-arrhythmic activity. Pro-arrhythmic activity was greatest in PV cells and the frequency was greater during the rest phase (ZT0-12) in both cell types. In contrast, the circadian rhythm in APD90 differed between cell type, with the longest APD­­90 recorded during the active phase in PV cells (ZT12-24) but during the rest phase in LAA cells. Pro-arrhythmic activity was increased by NA and decreased by ACh in both cell types with maximal effect during the rest phase. Conclusion Circadian variation in APD90 and proarrhythmic-activity has been demonstrated in isolated proximal PV and LAA cardiomyocytes, with differences in rhythm between the two cell types. RNA sequencing suggests the presence of peripheral clocks in LAA and PV cardiomyocytes. Understanding these mechanisms is important in development of future therapeutic options for AF.

The Effect of Jaripunktur on During Pain The Active Phase in Laboring Mothers at Independent Midwifery Clinics Y in Cimahi City

Labor pain is a major problem that is generally felt and experienced by all laboring women during the labor process. If not promptly addressed, this pain can induce excessive anxiety and fear in mothers during labor. This of course can cause labor to be prolonged and labor pain to feel more intense. The purpose of this study was to determine the effect of Jaripunktur (finger meridian points, LI 4 and SP 6) on pain during active phase I in laboring women at INDEPENDENT MIDWIFERY CLINICS Y in Cimahi City. The study was implemented through a Quasi-Experimental approach, utilizing a control group design with pre-test and post-test on two groups. The statistical analysis employed is the Wilcoxon test, with the p-value <0.05. This research involved a total of 38 participants, all of whom were working mothers in the first stage of labor, split into two groups of 19 each for the intervention and control groups respectively. The study took place from November 17 to December 17, 2022, utilizing questionnaires for collecting data. Findings indicated that Jaripunktur's application positively influenced analgesia during the first stage of labor in the mothers studied. Given this study, midwives or other healthcare workers should apply Jaripunktur to women in active stage I labor.

Time-Separated Pulse Release-Activation of an Enzyme from Alginate-Polyethylenimine Hydrogels Using Electrochemically Generated Local pH Changes.

β-Glucosidase (EC 3.2.1.21) from sweet almond was encapsulated into pH-responsive alginate-polyethylenimine (alginate-PEI) hydrogel. Then, electrochemically controlled cyclic local pH changes resulting from ascorbate oxidation (acidification) and oxygen reduction (basification) were used for the pulsatile release of the enzyme from the composite hydrogel. Activation of the enzyme was controlled by the very same pH changes used for β-glucosidase release, separating these two processes in time. Importantly, the activity of the enzyme, which had not been released yet, was inhibited due to the buffering effect of PEI present in the gel. Thus, only a portion of the released enzyme was activated. Both enzymatic activity and release were monitored by confocal fluorescence microscopy and regular fluorescent spectroscopy. Namely, commercially available very little or nonfluorescent substrate 4-methylumbelliferyl-β-d-glucopyranoside was hydrolyzed by β-glucosidase to produce a highly fluorescent product 4-methylumbelliferone during the activation phase. At the same time, labeling of the enzyme with rhodamine B isothiocyanate was used for release observation. The proposed work represents an interesting smart release-activation system with potential applications in biomedical field.

Serum Proteomic Profiles of Patients with Chronic Recurrent Multifocal Osteomyelitis.

Chronic recurrent multifocal osteomyelitis (CRMO) is an autoinflammatory disease characterized by sterile bone inflammation; however, its pathophysiology is poorly understood. Thus, this study aimed to characterize the serum proteomic profiles of patients with CRMO to better understand the molecular mechanisms underpinning CRMO pathogenesis. Proteomic profiling of the sera collected from 11 patients with CRMO (five patients were in active phase, six were in inactive phase) was conducted using liquid chromatography-mass spectrometry. Sera from four children without inflammatory diseases were used as controls. Pathway analysis was performed to identify the upregulated and downregulated proteins in patients with active CRMO. Compared with the control group, 19 and 41 proteins were upregulated and downregulated, respectively, in patients with active CRMO. Pathway and process enrichment analyses revealed that axon guidance was the most enriched category of upregulated proteins in patients with active CRMO, followed by neutrophil degranulation and mitogen-activated protein kinase cascade regulation. In comparison to patients with inactive CRMO, 36 proteins, including 11 keratin proteins, were upregulated and highly enriched in the intermediate filament organization category. Rho GTPase pathway-related proteins were downregulated in ibuprofen-treated patients. Proteomic analysis identified upregulated proteins in the sera of patients with acute CRMO. These proteins can be used as biomarkers for disease diagnosis and activity. Furthermore, we anticipate that this study will contribute to a deeper understanding of the pathophysiology of CRMO, which, in turn, will contribute to the discovery of potential novel therapeutic targets.

Refining the active phases of silver/nickle-based catalysts achieves a highly-selective reduction of nitrate to ammonium at low overpotential

The electrocatalytic conversion of NO3‾ to NH3 (NO3RR) with elevated activity and exceptional selectivity at low potential remains a formidable challenge. Herein, the A-Ag@Ni/Ni(OH)2 NWs with atomic-level Ag/Ni interfaces were synthesized via electrochemical activation of Ag@Ni/Ni(OH)2 NWs at −1.05 V vs. RHE for 1 hour, and subsequently employed for electrocatalytic NO3RR. Specially, Ag sites could afford active centers for the adsorption of NO3‾ and convert it to NO2‾. Furthermore, Ni/Ni(OH)2 sites as vibrant centers for electrocatalytic H2O splitting, generating atomic H on the catalyst surface (Hads), thereby facilitating the rapid conversion of NO2‾ to NH3 via the Hads-mediated pathway. DFT calculations further substantiate that the Hads-mediated pathway is thermodynamically more favorable than the electron reduction pathway, the former of which facilitates the generation of NH3 and is an energy-efficient process, thus, the A-Ag@Ni/Ni(OH)2 NWs show outstanding electrocatalytic activity and selectivity for NO3‾-to-NH3 transformation at low potential.

Modulating the electrocatalytic reduction of CO2 to CO via surface reconstruction of ZnO nanoshapes

The electrocatalytic conversion of carbon dioxide (CO2) into valuable chemicals presents a promising strategy for closing the carbon cycle. In this study, we synthesized zinc (Zn) catalysts through hydrothermal methods using either polyvinylpyrrolidone (PVP) or cetyltrimethylammonium bromide (CTAB) as stabilizing agents. These catalysts proved highly efficient in converting CO2 into carbon monoxide (CO). Our findings revealed that ZnO, synthesized with different morphologies—namely, nanoneedles (ZnO-NN) and nanorods (ZnO-NR)—underwent significant electro-reconstruction, ultimately leading to the formation of hexagonal metallic Zn crystals, regardless of their initial characteristics. Utilizing ex-situ operando techniques, we elucidated that metallic Zn serves as the active phase for the CO2-to-CO conversion process. In a comparison, ZnO-NN catalysts demonstrated superior selectivity and stability, achieving 91.3% CO selectivity at a potential of −0.88 V vs. RHE (Reversible Hydrogen Electrode) due to the facile transformation of ZnO to metallic Zn. Remarkably, these catalysts maintained this level of performance for more than 17 h. Conversely, ZnO-NR catalysts exhibited a lower CO selectivity of 62.5% at a relatively higher potential of −0.98 V vs RHE.

In-situ activation of three-dimensional porous NiFe alloy: Synergistic NiFe hydroxide/alloy as composite active sites for efficiently catalyzing alkaline water splitting

The strategic engineering of bifunctional catalysts for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline media is critical for water-splitting technologies. This study presented a catalyst consisting of in situ grown nickel iron (NiFe) hydroxide/porous alloy composite catalytic sites on a nickel foam (NF) substrate. Initially, a porous NiFe alloy was electrodeposited onto NF, employing hydrogen (H2) bubbles as dynamic templates to induce a three-dimensional (3D) architecture. Subsequently, ultrathin layers of NiFe hydroxide nanosheets were synthesized in situ via electrochemical activation. The distinctive porous structure, coupled with the in-situ activated nanosheets, augmented the exposure of active sites, optimized electrolyte interaction, and expedited the expulsion of gaseous byproducts, collectively enhancing the kinetics of water electrolysis. The resultant a-Ni2Fe/NF demonstrated superior OER/HER activities, achieving overpotentials of merely 240 mV for OER and 183 mV for HER at a current density of 100 mA cm-2 in alkaline solution. Moreover, a voltage of just 1.53 V was requisite to attain a current density of 10 mA cm-2 for overall water splitting. Operando Raman spectroscopy revealed the formation of NiOOH and FeOOH active phases during HER, indicating the hydroxide’s role in adsorbing hydroxyl groups and shielding NiFe alloy’s H* adsorption sites from oxidation. The presence of the more reactive β-NiOOH phase was discerned during OER process, acting as an intermediate. This straightforward yet efficacious strategy heralded a new paradigm in the design of NiFe-based bifunctional catalysts, significantly bolstering the efficiency of water electrolysis catalysis.

Fenobam modulates distinct electrophysiological mechanisms for regulating excessive gamma oscillations in the striatum of dyskinetic rats

Gamma oscillations have been frequently observed in levodopa-induced dyskinesia (LID), manifest as broadband (60-120 Hz) and narrowband (80-110 Hz) gamma activity in cortico-striatal projection. We investigated the electrophysiological mechanisms and correlation of gamma oscillations with dyskinesia severity, while assessing the administration of fenobam, a selective metabotropic glutamate receptor 5 (mGluR5) antagonist, in regulating dyskinesia-associated gamma activity. We conducted simultaneous electrophysiological recordings in Striatum (Str) and primary motor cortex (M1), together with Abnormal Involuntary Movement Scale scoring (AIMs). Phase-amplitude coupling (PAC), power, coherence, and Granger causality analyses were conducted for electrophysiological data. The findings demonstrated increased beta oscillations with directionality from M1 to Str in parkinsonian state. During on-state dyskinesia, elevated broadband gamma activity was modulated by the phase of theta activity in Str, while M1 → Str gamma causality mediated narrowband gamma oscillations in Str. Striatal gamma power (both periodic and aperiodic power), periodic power, peak frequency, and PAC at 80 min (corresponding to the peak dyskinesia) after repeated levodopa injections across recording days (day 30, 33, 36, 39, and 42) increased progressively, correlating with total AIMs. Additionally, a time-dependent parabolic trend of PAC, peak frequency and gamma power was observed after levodopa injection on day 42 from 20 to 120 min, which also correlated with corresponding AIMs. Fenobam effectively alleviates dyskinesia, suppresses enhanced gamma oscillations in the M1-Str directionality, and reduces PAC in Str. The temporal characteristics of gamma oscillations provide parameters for classifying LID severity. Antagonizing striatal mGluR5, a promising therapeutic target for dyskinesia, exerts its effects by modulating gamma activity.

Post-resolution macrophages shape long-term tissue immunity and integrity in a mouse model of pneumococcal pneumonia

Resolving inflammation is thought to return the affected tissue back to homoeostasis but recent evidence supports a non-linear model of resolution involving a phase of prolonged immune activity. Here we show that within days following resolution of Streptococcus pneumoniae-triggered lung inflammation, there is an influx of antigen specific lymphocytes with a memory and tissue-resident phenotype as well as macrophages bearing alveolar or interstitial phenotype. The transcriptome of these macrophages shows enrichment of genes associated with prostaglandin biosynthesis and genes that drive T cell chemotaxis and differentiation. Therapeutic depletion of post-resolution macrophages, inhibition of prostaglandin E2 (PGE2) synthesis or treatment with an EP4 antagonist, MF498, reduce numbers of lung CD4+/CD44+/CD62L+ and CD4+/CD44+/CD62L-/CD27+ T cells as well as their expression of the α-integrin, CD103. The T cells fail to reappear and reactivate upon secondary challenge for up to six weeks following primary infection. Concomitantly, EP4 antagonism through MF498 causes accumulation of lung macrophages and marked tissue fibrosis. Our study thus shows that PGE2 signalling, predominantly via EP4, plays an important role during the second wave of immune activity following resolution of inflammation. This secondary immune activation drives local tissue-resident T cell development while limiting tissue injury

Initial evaluation of humidity profiles retrieved by the EOS-07 millimetre-wave humidity sounder

ABSTRACT The vertical profiles of specific humidity in the troposphere measured by the millimetre-wave humidity sounder (MHS) onboard of the Earth Observation Satellite (EOS)-07 (Microsoft 2B) are validated using ground-based radiosonde observations during July-August 2023. MHS onboard EOS-07 (hereafter referred as EOS-07/MHS) is a 6-channel cross-track scanning radiometer operating in the 183.31 ± 16.25 GHz band. The EOS-07 observations are used to retrieve three-dimensional specific humidity profiling from 1000 hPa (surface) to 100 hPa (16 km) atmospheric pressure levels with a spatial resolution of 10 km at nadir. The EOS-07/MHS measurements over India have a high correlation coefficient of 0.98 with the radiosonde observations. The mean relative bias is found to be 0.44 ± 0.55 g kg−1 below 350hPa and 2.8 ± 2.3 g kg−1 above 350 hPa. It is also found that above the 350 hPa level, MHS seems to be systematically overestimating the radiosonde measurements. After that, the EOS-07/MHS measurements are used to construct the diurnal variation of humidity during the active phases of the Indian summer monsoon. The observations are consistent with the present understanding of the Indian summer monsoon system. The present results are very encouraging and demonstrate the great potential of EOS-07/MHS observations of humidity for meteorological application, especially in understanding the hydrological cycle.

H3K27me3 Expression Level and Its Epigenetic Regulation Mechanisms in Th17 Cell Differentiation in Patients With Ankylosing Spondylitis

To investigate the roles of histone H3K27me3 methylation and its regulatory enzymes JMJD3 and EZH2 in the differentiation of Th17 cells in ankylosing spondylitis (AS), to unveil their potential involvement in the pathogenesis of AS, and to provide new strategies and targets for the clinical treatment of AS by analyzing the methylation state of H3K27me3 and its interactions with Th17-related factors. A total of 84 AS patients (42 active AS patiens and 42 patients in the stable phase of AS) were enrolled for the study, while 84 healthy volunteers were enrolled as the controls. Blood samples were collected. Peripheral blood mononuclear cells were isolated. ELISA assay was performed to examine Th17 cells and the relevant cytokines IL-21, IL-22, and IL-17. The mRNA expressions of RORc, JAK2, and STAT3 were analyzed by RT-PCR, the protein expressions of RORc, JAK2/STAT3 pathway protein, H3K27me3 and the relevant protease (EZH2 and JMJD3) were determined by Western blot. Correlation between H3K27me3, EZH2 and JMJD3 and the key signaling pathway molecules of Th cell differentiation was analyzed by Pearson correlation analysis. The mRNA expressions of RORc, JAK2, and STAT3 were significantly higher in the active phase group than those in the stable phase group ( P<0.05). The relative grayscale values of H3K27me3 and EZH2 in the active phase group were lower than those of the stable phase group, which were lower than those of the control group, with the differences being statistically significant ( P<0.05). The relative grayscale values of JMJD3, RORc, JAK2, pJAK2, STAT3, and pSTAT3 proteins were significantly higher in the active phase group than those in the stable phase group, which were higher than those in the control group (all P<0.05). The proportion of Th17 and the expression level of inflammatory factors in the active period group were higher than those in the other two groups (P<0.05). H3K27me3 was negatively correlated with RORc, JAK2, STAT3, and IL-17, JMJD3 was positvely correlated with JAK2, STAT3, and IL-17, and EZH2 was negatively correlated with JAK2, STAT3, and IL-17 (all P<0.05). The low expression of H3K27me3 in AS is influenced by the gene loci JMJD3 and EZH2, which can regulate the differentiation of Th17 cells and thus play a role in the pathogenesis and progression of AS.

Enhancing Surgical Safety: Microbiological Air Control in Operating Theatres at University Medical Centre Maribor.

the aim of the study was to assess microbiological air quality in operating theatres by determining the level of microbiological contamination of the air and critical surfaces using the passive air sampling method and compliance of the operating theatre staff with infection control measures. The prospective study was conducted in the surgical block of the University Medical Centre Maribor. For two months continuously, ten operating theatres were assessed for microbial contamination of air and surfaces during quiet and active times of the day. A passive air sampling method with Petri dishes on an agar specially adapted for this purpose (plate count agar) was used. In addition, ten surgical procedures were observed to assess staff compliance with recommended practises. Air samples met microbiological standards in all operating theatres. In both sampling sessions of the day (quiet and active periods), microbial contamination of the air was always within the limit of 10 CFU/m3. The average number of bacterial colonies was zero to two during quiet phases and one to four during active phases. Approximately 60% of the isolates from the operating theatres belonged mainly to the genus Staphylococcus: S. epidermidis (36% of the isolates), S. hominis (17.5%) and S. haemolyticus (5.5%). The rest were identified as Streptococcus anginosus (23%) and Bacillus sp. (18%). Pathogenic bacteria and moulds were not present. In regard to staff compliance with good surgical practise, the former varied by behaviour and function, with non-compliance in pre-operative skin preparation and operating theatre congestion being notable. The cleanliness of the environment was satisfactory. Microbiological air control is extremely important for the safety and success of both surgical and postoperative practises. In spite of good results obtained in the study, further improvements in surgical staff compliance with good surgical practise are essential to reduce surgical site infections.

Recent progress in understanding the nature of active sites for methanol synthesis over Cu/ZnO catalysts

Copper-zinc-alumina (Cu/ZnO/Al2O3) has been utilized as the leading catalyst for industrial methanol synthesis via hydrogenation of CO and CO2 for more than 50 years. Understanding the nature of active Zn sites at the atomic level is vital for gaining insight into the reaction mechanism and rational design of more efficient Cu/ZnO catalysts for methanol synthesis but remains greatly challenging and has been intensively debated for decades. In this mini-review, we first describe the fundamental insights obtained from well-defined model catalysts and then summarize the recent experimental evidence with respect to dynamic structural and electronic changes in the active Zn phase under realistic working conditions by in situ/operando microscopy/spectroscopy and surface site titration using probing molecules. In the following, we discuss the catalytic mechanism of diverse active structures by theoretical calculations and simulations. Therefore, the critical role of interfacial sites between metallic Cu and ZnO, especially those with oxygen defects, in methanol synthesis via CO2 hydrogenation is emphasized. Finally, we discuss the technical challenges and perspectives in understanding the origins of this Cu-ZnO synergy and rational design of next-generation Cu-based methanol synthesis catalysts.

Identifying the Active Phase on Atomically Dispersed Catalysts for Propane Dehydrogenation: Positively Charged vs Metallic Transition Metals

Identifying the Active Phase on Atomically Dispersed Catalysts for Propane Dehydrogenation: Positively Charged vs Metallic Transition Metals

Modulating charge storage mechanism of cobalt-tungsten nitride electrodes using in situ formed metal-p-n heterojunction for ultrahigh energy density supercapattery

Supercapatteries combine both diffusion-controlled and capacitive charge storage mechanisms to simultaneously deliver exceptional power density and energy density. Though developing materials that combine both charge storage mechanisms for use as supercapattery electrodes is difficult, one solution has been to modify a material that inherently has one of these mechanisms so that it also exhibits the other form of charge storage. In the present study, we modulate the electrochemical reconstruction of a W5N4 electrode to modify its charge storage from pure battery-type to pseudocapacitive, thus enhancing its specific capacity and cyclic stability. This modulation was carried out by embedding Co in W5N4 (Co-W5N4), leading to the formation of W and N-doped Co(OH)2 as an active phase and producing a high specific capacity of 2211 C g−1 at 2 A g−1. The incorporation of a thin layer of TiO2 (Co-W5N4/TiO2) through atomic layer deposition minimized tungsten dissolution during reconstruction, thus generating in-situ a dynamic metal–p-n junction heterostructure (Co-W5N4||Co(OH)2||TiO2) that modulated the charge flow, achieving high-rate capability (retaining 53.1 % at 50 A g−1 compared to 2 A g−1) and cyclic stability (82.8 % after 100,000 cycles at a high current density of 40 A g−1). As illustrated by operando electrochemical impedance spectroscopy and physicochemical analysis, the dynamic response of metal–p-n junction sustains the pseudocapacitive charge storage mechanism at high current rate. This study thus demonstrates the formation of metal-p-n heterojunction and describes its dynamic response under actual charge/discharge operating conditions, providing useful information for the design of energy storage electrodes and energy conversion catalysts.

Unified mechanistic understanding on CO2 sorption by Na-doped Li4SiO4: Experimental and DFT study

The addition of molten Na2CO3 can drastically accelerated the extremely slow sorption kinetics of Li4SiO4-based CO2 sorbents in the sorption enhanced reforming process. However, the lack of a unified consensus about the effect of doped Na2CO3 on the CO2 capture process, now delays the development of more-effective Li4SiO4 sorbents. Here, sorption tests, sturactural characterzations and periodic density functional theory calculations were combined to develop a better mechanistic understanding CO2 sorption on Na-doped Li4SiO4. The Na-doped Li4SiO4 exhibited a better CO2 capture performance than pure Li4SiO4 even below the melting point of any eutectic mixtures. Structural characterizations revealed that rather than generating physical favorable characteristics, the Na doping substituted at the Li site and created lithium–sodium orthosilicates (Li4-xNaxSiO4). Theoretical calculations agreeing with experimental results further demonstrated that Li4-xNaxSiO4 presented a weaker Na-O bond and generated more active phases (quasi Li2O groups) for larger sorption energies, more charge transfers and stronger CO32– bond formation, in turn providing more reactive sites for enhanced CO2 chemisorption as comparing with pure Li4SiO4. Finally, we propose a new and unified sorption mechanism independent of the traditional “melting layer” explanation.