Local Changes Research Articles

Probing the Depths of Electrocatalysis Systems: X-Ray Absorption Spectroscopy Reveals Catalyst Behavior

X-ray absorption spectroscopy (XAS) is a powerful experimental technique used to study the electronic structure and local environment of atoms in a material. It provides valuable insights into the chemical bonding, oxidation states, and coordination geometry of elements. XAS has been widely applied in various fields of electrochemistry, including popular topics like the hydrogen evolution reaction (HER), oxygen reduction reaction (ORR), and CO2 reduction reaction (CO2RR).Despite the growing recognition of the practical importance of XAS techniques, correlating experimental spectroscopy with the working mechanisms and deciphering the structure of the electrochemical interface under reaction conditions remains challenging. In the case of CO2RR, we utilized operando XAS to investigate multiple Cu-based catalysts in different cell configurations. Our findings revealed that altering the reaction environment can induce an alternative pathway for catalyst structural changes. Moreover, operando XAS demonstrated that the reduction of Cu oxide catalysts is not solely governed by applied potentials but is also influenced by mass transport and other parameters. For ORR, in situ XAS not only provides information about the local environment changes of Pt-based catalysts but also unveils surface properties through △μ-X-ray adsorption near-edge spectroscopy (△μ-XANES). This further aids in the discovery of degradation mechanisms in proton exchange membrane fuel cells (PEMFCs). In the case of HER, in situ XAS enables characterization beyond catalysts and extends to the electrochemical interface.Overall, XAS techniques play a crucial role in understanding the electronic structure and local environment of atoms in electrochemical systems, shedding light on reaction mechanisms and catalyst performance under realistic conditions Acknowledgement The authors thank the funding source from Liquid Sunlight Alliance under the U.S. DOE, Office of Science, Office of Basic Energy Sciences, Fuels Award Number DE-SC0021266 and the Laboratory Directed Research and Development Program of the Lawrence Berkeley National Laboratory under the U.S. DOE Contract No. DE-AC02-05CH11231.

(Invited) Probing Local Ion Insertion through Operando AFM

Electrode volume change during ion insertion or intercalation has been one of the main failure mechanisms for several energy storage devices, especially Li-based batteries. Fundamental understanding of the relationship between the amount of the ions/charge stored and the induced volume changes of the hosting electrodes, and how this relationship impact the materials’ performance are necessary to develop the next generation batteries. However, most of the studies on the volume change were based on bulk techniques, which study the entire electrode including binders and additives. Here, we use operando atomic force microscopy (AFM), which allows tracking local volume changes and other mechanical responses with sub-nanometer spatial resolution under the conditions close to the device operation.In this work, we monitored electrode volume change via operando AFM and demonstrated the electro-chemo-mechanical coupling behaviors during proton insertion into WO3 materials. The concept of mechanical cyclic voltammetry (mCV) curves was developed, and the relationship between electrochemical current and strain was investigated with simplified models. The results revealed multiple ion-intercalation processes with different mechanical responses are involved during electrode cycling. Local heterogeneity was investigated via mCV mapping, confirming that the charging mechanisms varied across the electrode. These local variations could be further correlated to local morphology, crystal orientations, or chemical compositions. We further demonstrate that the mCV approach is applicable to a variety of energy storage materials (e.g., birnessite, MXene and metal nitrides) with the increasing complexity of current-deformation relationships.

Material Dynamics of Nickel (oxy)Hydroxide As an Alcohol Oxidation Electrocatalyst

Electrochemical alcohol oxidation is an attractive reaction for renewable-energy driven production of value-added chemicals, like precursors for acrylic (acrolein from glycerol) and nylon (adipic acid from cyclohexanol). Implementing selective, earth-abundant catalysts for alcohol oxidation can improve electrolyzer efficiency and economics. For example, replacing the energy intensive oxygen evolution reaction (OER) in CO2 electrolyzers with alcohol oxidation can decrease operating voltage by about 0.85 V and reduce electricity requirements up to 53% while also reducing carbon emissions from chemical production.1 Electrochemical alcohol oxidation catalyzed by as synthesized nickel oxyhydroxide (NiOOH) is hypothesized to proceed through two pathways, a chemical, redox pathway preferred by aldehydes (geminal diols in alkaline electrolyte), and a potential dependent pathway preferred by alcohols.2 Many studies have focused on understanding reaction mechanisms and device performance, however, transition metal alcohol oxidation catalysts, such as NiOOH, are known to undergo reduction/oxidation, phase changes, and even dissolution in the same potential window as alcohol oxidation.3 It is still unclear how these processes affect catalyst material stability and electrochemical performance.In this work, we probe the performance stability and material stability of Ni(OH)2 for alcohol oxidation in alkaline media through electrochemical cycling and chronoamperometry. We use a rigorously Fe-free environment to mitigate performance impacts from Fe-contamination common in non-purified alkaline electrochemical studies.4 We show that the rate of change of alcohol oxidation current density (mA cm-2) depends on reaction pathway (redox vs. potential dependent), alcohol concentration, and side chain structure. Using EC-MS and NMR, we also probe changes in performance in yield and selectivity by quantifying oxidation products, including oxygen gas. These changes in performance are correlated to material changes through monitoring dissolution with on-line ICP-MS. Furthermore, to disentangle the role of potential and reactant (e.g. alcohol or water) on stability, we elucidate oxidation state and local structural changes using in situ X-ray Absorption Spectroscopy (XAS). Insights from this rigorous model system are directly translatable to the broader goal of developing efficient, long-lasting catalysts for industrial deployment of electrochemical organic reactions powered by clean energy. References. Verma, Sumit, Shawn Lu, and Paul JA Kenis. Nature Energy 4.6 (2019): 466-474.2.Bender, Michael T., and Kyoung‐Shin Choi. ChemSusChem 15.13 (2022): e202200675.Klaus, Shannon, et al. The Journal of Physical Chemistry C 119.13 (2015): 7243-7254Wei, Lingze, et al. ACS Catalysis 13.7 (2023): 4272-4282.

Extended Cycle Life Pb-Ion Batteries with High Coulombic Efficiency Exceeding 99.96% from Al/Pb Bimetallic Eutectic Electrolyte

Following renewable energy development, batteries are the most crucial way to establish an energy storage system. In the past hundred years, lead-acid batteries have been widely applied in industrial and vehicle applications. Their low cost, simple manufacturing, and good safety can compete with lithium-ion batteries. However, some challenges still exist, e.g., poor low-temperature performance and short cycle life; aqueous solution is the reason that oxygen evolves from positive electrodes, resulting in positive active material detached from the electrode. Thus, developing novel lead-ion batteries to replace lead-acid batteries is a significant issue. In metal-ion batteries research, deep eutectic solvent (DES) has been well developed in recent years due to its high thermal stability and wide electrochemical window. Herein, a new Al/Pb bimetallic eutectic electrolyte (BEE) composed of aluminium perchlorate (Al(ClO4)3·9H2O), lead perchlorate (Pb(ClO4)2·3H2O), and succinonitrile (SN) with acetonitrile (ACN) as an additive, mixing in molar ratio. To realize the medium effect in this electrolyte, the BEE is compared with concentrated Pb(ClO4)2 aqueous solution. The ion conductivity, viscosity, and thermal stability depend on the metallic salt/SN ratio, and we proposed that the optimized molar ratio is 1:1:12:5. It exhibits outstanding thermal stability within − 50 to 50 °C. From Fourier-transform infrared spectroscopy (FTIR) spectrum analysis in BEE, the O-H stretching decreased, and the ClO4 - stretching band increased, compared to the concentrated Pb(ClO4)2 aqueous solution; it can be understood that O-H interaction between Pb2+ and ClO4 - is weakened; meanwhile, ClO4 - ions participated in first solvation shell. This variation reduces the desolvation energy of Pb2+ to facilitate smoother lead plating/stripping and enables better electrochemical performance. To validate the effect of the solvation structure variation, assembling the Pb/Pb symmetric cell and Pb/Platinum (Pt) asymmetric cell are essential methods. Pb/Pb cell maintains a stable voltage hysteresis of about 20 mV even cycling 2500 h at the current density of 0.5 mA cm-2, Pb/Pt cell under galvanostatic conditions successfully performs highly reversible Pb plating/stripping, achieved average coulombic efficiency (ACE) >99.96% in BEE for more than 1000 h at current density 0.5 mA cm-2. Furthermore, we utilize BEE in Na3V2(PO4)3(NVP) and natural graphite (NG) as cathode material; the reversible Pb2+ and ClO4 - (de-)intercalation are respectively observed in Pb/NVP and Pb/NG full cell, Pb/NVP cell exhibited long-term cycling stability with 80.95% capacity retention and 98.21% ACE after 600 cycles at a current density of 100 mA g-1, then Pb/NG cell remains high discharge voltage plateau (≈1.7V) with 72% capacity retention after 200 cycles at a current density of 100 mA g-1. Electrochemical impedance spectroscopy (EIS) of Pb/NVP in BEE-1:1:12:0 and 1:1:12:5 shows that adding the ACN additive can decrease the solution resistance (Rs) and charge transfer resistance (Rct) of the cell. Ex-situ X-ray photoelectron spectroscopy (XPS) was performed on the Pb surface at the charging state, observing that Al species are co-deposited, revealing the synergistic effect between Aluminium perchlorate and Lead perchlorate. From the ex-situ X-ray diffraction (XRD) patterns of cycled NVP and NG cathode at charge/discharge states, some irreversible variation of peak position occurred, indicating that ion (de-)intercalation after operation; these results demonstrate BEE performed bi-functional ion (Pb2+ and ClO4 -) intercalation phenomenon. To further confirm the Pb2+ dynamic in the NVP cathode at charge/discharge progress, the X-ray absorption spectroscopy (XAS) characterization was applied. The comparison of XANES spectra collected at the V K-edge, the XANES shift to lower energy during discharging, this exhibition is consistent with reduction reaction of V4+ to V3+, the EXAFS spectra show the local structure change of V-P/Na/Pb bonds. The EXAFS spectra at the Pb LIII-edge indicated that the Pb-O distance is shortened during discharging; the abovementioned results demonstrate the Pb2+ (de-)intercalation process in the NVP structure.In conclusion, this work proposed a novel bimetallic eutectic electrolyte for potential lead-ion batteries that enables stable Pb plating/stripping. The cycle-life and capacity retention of Pb/NVP and Pb/NG full-cell with BEE is significantly improved by adding acetonitrile (ACN) additive. The XAS characterization further confirmed the (de-)intercalation of Pb2+ in the NVP cathode. A stable, high-voltage, and high-capacity positive electrode is needed, allowing the reuse of secondary lead metal to be applied to next-generation energy storage. Figure 1

SCN as a local probe of protein structural dynamics.

The dynamics of lysozyme is probed by attaching -SCN to all alanine residues. The one-dimensional infrared spectra exhibit frequency shifts in the position of the maximum absorption of 4 cm-1, which is consistent with experiments in different solvents and indicates moderately strong interactions of the vibrational probe with its environment. Isotopic substitution 12C → 13C leads to a redshift by -47 cm-1, which agrees quantitatively with experiments for CN-substituted copper complexes in solution. The low-frequency, far-infrared part of the protein spectra contains label-specific information in the difference spectra when compared with the wild type protein. Depending on the position of the labels, local structural changes are observed. For example, introducing the -SCN label at Ala129 leads to breaking of the α-helical structure with concomitant change in the far-infrared spectrum. Finally, changes in the local hydration of SCN-labeled alanine residues as a function of time can be related to the reorientation of the label. It is concluded that -SCN is potentially useful for probing protein dynamics, both in the high-frequency part (CN-stretch) and in the far-infrared part of the spectrum.

GGNBP2 regulates histone ubiquitination and methylation in spermatogenesis

ABSTRACT Gametogenetin binding protein 2 (GGNBP2) was indispensable in normal spermatids for transformation into mature spermatozoa in mice, and when Gametogenetin binding protein 2 is bound to BRCC36 and RAD51, the complex participates in repairing DNA double-strand breaks (DSB) during the meiotic progression of spermatocytes. Ggnbp2 knockout resulted in the up-regulation of H2AK119ubi and down-regulation of H2BK120ubi in GC-2 cells (mouse spermatogonia-derived cell line) and postnatal day 18 testis lysate. Our results also demonstrated that Gametogenetin binding protein 2 inducedASXL1 to activate the deubiquitinating enzyme BAP1 in deubiquitinating H2A, while Gametogenetin binding protein 2 knockout disrupted the interaction between ASXL1 and BAP1, resulting in BAP1 localization change. Furthermore, the Gametogenetin binding protein 2 deletion reduced H2B ubiquitination by affecting E2 enzymes and E3 ligase binding. Gametogenetin binding protein 2 regulated H2A and H2B ubiquitination levels and controlled H3K27 and H3K79 methylation by PRC2 subunits and histone H3K79 methyltransferase. Altogether, our results suggest that Ggnbp2 knockout increased DNA damage response by promoting H2A ubiquitination and H3K27trimethylation (H3K27me3) and reduced nucleosome stability by decreasing H2B ubiquitination and H3K79 dimethylation (H3K79me2), revealing new mechanisms of epigenetic phenomenon during spermatogenesis. Gametogenetin binding protein 2 seems critical in regulating histone modification and chromatin structure in spermatogenesis.

GC Insights: Communicating long-term changes in local climate risk using a physically plausible causal chain

Abstract. Directly linking greenhouse gas emissions or global warming to experiences of local climatic changes is a potentially important communication tool. Using observations, we develop a physically plausible “causal chain” visualisation to demonstrate the connections between global carbon dioxide emissions and local climate events. We highlight how increased flood risk in one river basin in the UK could be discussed with people directly affected by recent floods.

Morphological Measurement and Clinical Significance of Abnormal Development of Distal Femur with Hemophilia Knee Arthritis: A Consideration on the Renewal of Total Knee Prosthesis.

The knee joint of hemophiliacs may face the result of local morphological changes due to long-term irritation of synovitis. This study aims to elucidate the morphological characteristics of distal femur in hemophilic arthritis (HA) and compare the compatibility of three types of prostheses with the anteroposterior (AP) and mediolateral (ML) dimensions of the femoral osteotomy surface. This study retrospectively and randomly selected 50 patients with HA registered for treatment at our hospital from June 2016 to August 2022 as the study subjects, with an equal number of male osteoarthritis (OA) patients and healthy male individuals set as the control group. This study used medical digitalization software to simulate osteotomies on the distal femur during total knee arthroplasties (TKA) for 50 patients with HA, OA patients, and the healthy population, respectively, and measure the morphological parameters to compare with three commonly used femoral components of TKA in clinical practice. The differences between the femur resection of anteroposterior and mediolateral (FRAP, FRML) osteotomy surface and the prosthesis's BOX-AP/ML were compared in three prostheses. One-way ANOVA and multiple Kruskal-Wallis H test were used for the normal or non-normal distribution data, and pairwise comparisons between groups were conducted using the Bonferroni method, and the linear correlation analysis was utilized to assess the relationship between section femoral morphological data and prosthesis parameters. In HA patients, the morphological characteristics of the distal femur were shown as shorter than femur AP (FAP), medial and lateral condyle anterior-posterior dimension (FMCAP, FLCAP), notch width (NW), posterolateral condyle height (PLCH), posteromedial condyle width (PMCW), and posterior condylar axis length (PCAL) dimension. They had comparatively smaller femur section aspect ratios (p < 0.005). They showed longer posterolateral condyle width (PLCW), anterior condyle mediolateral dimension (FRACML), anterolateral condyle height (ALCH), and femur resection anterior condylar mediolateral (FRACML) dimension (p < 0.005). They showed larger distal femur aspect ratio and resection aspect ratio (FAR, FRAR, p < 0.005). All selected prostheses showed ML undercoverage under similar AP dimensions, and ML undersizing of Attune systems was more obvious in three femoral prostheses. The distal femur morphological change of HA patient is shown as smaller AP dimension, narrow posterior condyle spacing, lower and shallower trochlear, thinner anterior condyle, wider and lower intercondylar notch and higher posterior-lateral condyle. The selected prostheses showed ML undercoverage under similar AP dimensions. This typical morphological tendency of the distal femur seems to warrant consideration in the process of knee joint prosthesis upgrading.

Visual Field Defects and Retinal Nerve Fiber Layer Thickness in Migraine Patients: A Study From a Tertiary Care Center in India.

Background This study aimed to analyze the visual field changes and retinal nerve fiber layer (RNFL) thickness during the headache phase of migraine attacks among migraine patients compared with controls. Methodology A prospective, case-control study was conducted at a tertiary care center in Palakkad, Kerala from January 2022 to August 2023. This study included 50 migraine patients and 50 age/gender-matched controls. Adults aged 20-40 years with a more than three-year history of migraine were included in this study and those who had systemic or ocular pathologies were excluded. All 100 subjects underwent complete ocular examination, including full threshold 24-2 automated perimetry for visual field analysis and optical coherence tomography for analyzing RNFL thickness. Statistical analysis was done using SPSS Statistics Version 25 (IBM Corp., Armonk, NY, USA). Results In this study, the average age for cases was 29.24 ± 5.10 years, and for controls was 30.12 ± 6.20 years. Gender distribution was identical between cases and controls with 29 (58%) females and 21 (42%) males. Among the 50 migraine patients, 22 (44%) had generalized, while 28 (56%) had localized field defects during the headache phase of migraine attacks. There was a statistically significant (p < 0.001) difference in superior quadrant RNFL thickness between cases (114.08 ± 12.25) and controls. Conclusions We found that RNFL thinning in the superior quadrant and non-specific localized visual field changes occur during migraine attacks. We conducted this study in a tertiary care center as very few studies in our country have revealed visual field changes during migraine headache attacks.

Wind-Sea and Swell Climate in the Black and Azov Seas, Based on 42-Year Spectral Wave Hindcast

Long-term wave climates of the Black and Azov Seas are widely assessed based on the bulk wave parameters of the mixed sea. However, studies based on spectral wave partitions are rarely documented. Assessment of the wave climate based on the individual wave systems provides a more reliable description of the sea states' characteristics and the variability in the long-term wave climate. For instance, the wind-sea climate may reflect a real change in the local climate. However, local change in swell characteristics may not necessarily reflect a change in the local climate, and it can locally influence the mixed sea climate variability. This study assessed the spatial distributions of the long-term averages and maxima of mixed seas, wind-sea, and swell partitions at annual and seasonal scales. The contributions of wind-sea and swell partitions to the mixed-sea were computed, and their spatial and temporal variability was also assessed for overall and extreme sea state conditions. Finally, the occurrence in main wave systems' directions and occurrence of crossing, opposing, and following wind-sea and swell interactions were computed. The wind-sea contribution to the mixed-sea exceeds 70 % in all Black Sea and >95 % in the Azov Sea. The swells are more dominant on the Northeastern and Northwestern Black Sea basins. Thus, the results show spatial and temporal variability in the wind-sea climate close to the mixed sea but largely different compared to the swell climate. The inter-annual trends in the swell partitions and wind-sea are inversed at some locations.

An Optimal Weighted Ensemble Machine Learning Approach to Accurate Estimate the Coastal Boundary Layer Height Using ERA5 Multi‐Variables

AbstractThe coastal boundary layer height (CBLH/Coastal‐BLH) is critical in determining the exchange of heat, momentum, and materials between the land and ocean, thereby regulating the local climate and weather change. However, due to the complexity of geographical characteristics and meteorological conditions, accurate estimation of the CBLH remains challenging. Herein, based on continuous high‐resolution measurements of CBL performed from November 2019 to April 2020 in coastal Ningbo city in eastern China, an optimal weighted ensemble model (OWEM) integrating multi‐meteorological variables of the ERA5 reanalysis data sets is constructed and validated to estimate the CBLH. The mean absolute percentage error of the derived CBLH by OWEM is as low as 3%–5%, significantly lower than that of 36%–65% of the ERA5 CBLH products. Furthermore, three categories of different weather scenarios, that is, sunny, cloudy, and rainy, are separately discussed, and OWEM shows greater performance and higher accuracies in comparison with the traditional Least Absolute Shrinkage and Selection Operator, Random Forest, Adaboost, LightGBM, and ensemble model, among which, OWEM under fair weather days behave best, with a robust R2 of 0.97 and a minimum mean absolute error (MAE) of 23 m. Further training results based on wind flow classification, that is, land breeze, sea breeze, and parallel wind, also indicate the outperformance of OWEM than other models, with a relatively large error in parallel wind of 50 m. Subsequent analysis of the Shapley Additive Explanations method strongly correlated with model feature importance, both reveal that thermodynamic factors such as temperature (T2m) and wind velocity (10 m U) are the major factors positively related to estimation accuracy during sunny days. Nevertheless, Relative Humidity dominates on rainy and cloudy days, TP on land breeze days, and dynamic variables like 10 m U and 10 m V on entire types of wind flow weather. In conclusion, the accurate estimation of CBLH from OWEM serves as a feasible and innovative approach, providing technical support for marine meteorology and related engineering applications, for example, onshore wind power, coastal ecological protection, etc.

Chromatin and gene regulation in archaea.

The chromatinisation of DNA by nucleoid-associated proteins (NAPs) in archaea 'formats' the genome structure in profound ways, revealing both striking differences and analogies to eukaryotic chromatin. However, the extent to which archaeal NAPs actively regulate gene expression remains poorly understood. The dawn of quantitative chromatin mapping techniques and first NAP-specific occupancy profiles in different archaea promise a more accurate view. A picture emerges where in diverse archaea with very different NAP repertoires chromatin maintains access to regulatory motifs including the gene promoter independently of transcription activity. Our re-analysis of genome-wide occupancy data of the crenarchaeal NAP Cren7 shows that these chromatin-free regions are flanked by increased Cren7 binding across the transcription start site. While bacterial NAPs often form heterochromatin-like regions across islands with xenogeneic genes that are transcriptionally silenced, there is little evidence for similar structures in archaea and data from Haloferax show that the promoters of xenogeneic genes remain accessible. Local changes in chromatinisation causing wide-ranging effects on transcription restricted to one chromosomal interaction domain (CID) in Saccharolobus islandicus hint at a higher-order level of organisation between chromatin and transcription. The emerging challenge is to integrate results obtained at microscale and macroscale, reconciling molecular structure and function with dynamic genome-wide chromatin landscapes.

Changed Seasonality and Forcings of Peak Annual Flows in Ephemeral Channels at Flagstaff, Northern Arizona, USA

Flood variability associated with urbanization, ecological change, and climatic change is of increasing economic and social concern in and around Flagstaff, Arizona, where flood hydrology is influenced by a biannual precipitation regime and the relatively unique geologic setting at the edge of the San Francisco Volcanic Field on the southern edge of the Colorado Plateau. There has been limited long-term gauging of the ephemeral channels draining the developed lands and dry coniferous forests of the region, resulting in a spaciotemporal gap in observation-based assessments of large-scale flooding patterns. We present new data from over 10 years of flood monitoring using a crest stage gauge network, combined with other channel monitoring records from multiple agency sources, to assess inter-decadal patterns of flood change in the area, with a specific emphasis on examining how various controls and disturbances have altered the character and seasonality of peak annual flows. Methods of analysis included the following: using Fisher’s Exact Test to compare the seasonality of flooding between historic data spanning the 1970s and contemporary data obtained since 2010; summarizing GIS-based spatial data and meteorological timeseries to characterize study catchment conditions and changes between flood study periods; and relating spatiotemporal patterns of flood seasonality and occurrences of notably large floods with catchment characteristics and environmental changes. Our results show systematic patterns and changes in Flagstaff-area flood regimes that relate to geologic and topographic controls of the varied catchment systems, and in response to records of climate variations and local catchment disturbances, including urbanization and, especially, high-severity wildfire. For most catchments there has been a shift from predominantly late winter to spring snowmelt floods, or mixed seasonal flood regimes, towards monsoon-dominated flooding, patterns which may relate to observed local warming and precipitation changes. Post-wildfire flooding has produced extreme flood discharges which have likely exceeded historical estimates of flood magnitude over decade-long monitoring periods by one to two orders of magnitude. We advocate for continued monitoring and the expansion of local stream gauge networks to enable seasonal, magnitude-frequency trend analyses, improved climate and environmental change attribution, and to better inform the many planned and ongoing flood mitigation projects being undertaken in the increasingly developed Flagstaff region.

Structural, morphological, and optical investigations of Mn-doped LaAlO3 perovskite obtained by microwave-assisted combustion and rapid calcination at low temperature

In this work, LaAlO3 perovskite was doped with 1, 2, 3, 5, 8, and 13 mol% of Mn using the microwave-assisted combustion method. The powders produced were heat treated at 700 °C and 900 °C for 10 min in an adapted microwave oven and then characterized by Thermogravimetric analysis (TG/DTG) and Differential Scanning Calorimetry (DSC), X-ray Diffraction (XRD) and Rietveld refinement, X-ray Photoelectron Spectroscopy (XPS), Fourier Transform Infrared Spectroscopy (FTIR), Raman, Ultraviolet–Visible Reflectance (UV–Vis), Field Emission Scanning Electron Microscopy (FE-SEM) and Energy Dispersive X-ray Spectroscopy (EDS). The materials produced doped with the highest concentration of Mn (13 %) showed a single-phase reduced crystallite size compared to the pure sample. The unit cell volumes increased compared to the pure material, while the oxidation state of the dopant was mainly Mn3+. The refinement data for the volume of the different polyhedral that comprise the LaAlO3 unit cell revealed a local change at both sites, which may also indicate Mn substitution at the A site. The heat treatment temperature did not change significantly, demonstrating the method's efficiency in producing perovskites at temperatures and times below those reported in the literature. The morphology observed was porous and irregular agglomerates, and the bandgap was 2.90 eV.

Probing charge redistribution at the interface of self-assembled cyclo-P5 pentamers on Ag(111)

Phosphorus pentamers (cyclo-P5) are unstable in nature but can be synthesized at the Ag(111) surface. Unlike monolayer black phosphorous, little is known about their electronic properties when in contact with metal electrodes, although this is crucial for future applications. Here, we characterize the atomic structure of cyclo-P5 assembled on Ag(111) using atomic force microscopy with functionalized tips and density functional theory. Combining force and tunneling spectroscopy, we find that a strong charge transfer induces an inward dipole moment at the cyclo-P5/Ag interface as well as the formation of an interface state. We probe the image potential states by field-effect resonant tunneling and quantify the increase of the local change of work function of 0.46 eV at the cyclo-P5 assembly. Our experimental approach suggest that the cyclo-P5/Ag interface has the characteristic ingredients of a p-type semiconductor-metal Schottky junction with potential applications in field-effect transistors, diodes, or solar cells.

Linking local climate scenarios to global warming levels: applicability, prospects and uncertainties

Abstract Global warming levels (GWLs) are increasingly becoming a central concept in climate change studies. In recent years, their integrative quality for climate change impact analysis has been demonstrated, and methodological advancements have helped to compensate for some inherent shortfalls of the concept. However, their applicability at the regional level is debatable, and no study to date has examined the possibility of linking local climate scenarios to GWLs. For the case of Austria, we have evaluated the relation between global and local warming patterns, and whether version changes of global climate models could be incorporated into local climate scenarios by means of the GWL concept, without updating the actual data. We applied the time sampling approach, where GWLs are determined as periods when global mean temperature anomalies cross a certain threshold. GWL periods were sampled both from the global models in the background of the local climate scenarios (CMIP5), and from an equivalent ensemble of newer-generation climate models (CMIP6). Uncertainties resulting from sampling GWLs from different global climate model ensembles were examined, and prospects for local climate change impact assessments were discussed. Accounting for updated global climate model versions might be useful when the changes at certain GWLs are related to fixed reference periods, but temperature increments between GWLs remained relatively constant across model versions, even on the local level. The study bridges a significant gap to link regional and local climate projections to GWLs. Climate change impacts assessments that build on those datasets can benefit from the integrative character of GWLs, making studies comparable across multiple disciplines and model versions, and thus fostering a way to communicate local climate change impacts more comprehensible.

Linking animal and human health burden: challenges and opportunities.

Quantifying the impact of poor animal health outcomes on human health represents a complex challenge. Using the disability-adjusted life year (DALY) metric as an endpoint, this article discusses how animal health outcomes can impact humans through three key processes: directly through zoonotic disease, indirectly via changes in yields and their impacts on nutrition and wealth, and finally, through indirect features associated with the agricultural industry, such as pharmaceuticals and climate change. For each process, the current state of the art and feasibility of global DALY-associated estimates are discussed. Existing frameworks for zoonoses already consider some key pathogens; ensuring completeness in the pathogens considered and consistency in methodological decisions is an important next step. For diet, risk factor frameworks enable a calculation of attributable DALYs; however, significant economic methodological developments are needed to ensure that local production changes are appropriately mapped to both local and global changes in dietary habits. Concerning wealth-related impacts, much work needs to be done on method development. Industry-related impacts require a focus on key research topics, such as attribution studies for animal antimicrobial resistance contributing to human outcomes. For climate change, a critical next step is identifying to what extent associated industry emissions are amenable to change should animal health outcomes improve. Allocation of finite funds to improve animal health must also consider the downstream impact on humans. Leveraging DALYs enables comparisons with other human health-related decisions and would represent a transformative way of approaching animal health decision-making should the obstacles in this article be addressed and new methods be developed.

Downhill skiing & climate change adaptation in Wisconsin: perspectives from key stakeholders

Climate change is currently impacting various facets of our local systems with many stakeholders and industries working to adapt to these changing conditions. There is a growing recognition that adaptation practices need to be directed within specific industries, communities, and stakeholders. A key area that is being impacted is the snow sports industry which is facing various challenges due to localized climatic changes. Previous work has indicated that climate change may leave these snow-dependent industries in the U.S. Midwest unviable in the future, so it is imperative to understand how these stakeholders are adapting to climate change and how they view the future of their industry. To do this, we conducted in-depth interviews with owners and operators in Wisconsin to understand 1) the climate change impacts they are facing, 2) their adaptation strategies, and 3) their views of the future of Wisconsin downhill skiing. Our results outline various environmental and social changes that participants associate with climate change and document their current adaptation strategies. Operators are optimistic about the future, but there is a recognition that adaptation practices and planning will likely intensify. This letter concludes with an outline for future research and support for adaptation practices that blend qualitative methods with physical and technological research that can aid this industry’s adaptation strategies.

Insight into structural dynamics involved in activation mechanism of full length KRAS wild type and P-loop mutants

KRAS protein is known to be frequently mutated in various cancers. The most common mutations being at position 12, 13 and 61. The positions 12 and 13 form part of the phosphate binding region (P-loop) of KRAS. Owing to mutation, the protein remains in continuous active state and affects the normal cellular process. Understanding the structural changes owing to mutations in GDP-bound (inactive state) and GTP-bound (active state) may help in the design of better therapeutics. To understand the structural flexibility due to the mutations specifically located at P-loop regions (G12D, G12V and G13D), extensive molecular dynamics simulations (24 μs) have been carried for both inactive (GDP-bound) and active (GTP-bound) structures for the wild type and these mutants. The study revealed that the local structural changes at the site of mutations allosterically guide changes in distant regions of the protein through hydrogen bond and hydrophobic signalling network. The dynamic cross correlation analysis and the comparison of the correlated motions among different systems manifested that changes in SW-I, SW-II, α3 and the loop preceding α3 affects the interactions of GDP/GTP with different regions of the protein thereby affecting its hydrolysis. Further, the Markov state modelling analysis confirmed that the mutations, especially G13D imparts rigidity to structure compared to wild type and thus limiting its conformational state in either intermediate state or active state. The study suggests that along with SW-I and SW-II regions, the loop region preceding the α3 helix and α3 helix are also involved in affecting the hydrolysis of nucleotides and may be considered while designing therapeutics against KRAS.

The Limits of Local Power: Business, Political Conflict, and Coastal Reclamation Projects in Makassar, Indonesia

Since the fall of Indonesia's Suharto regime in 1998, politics in Makassar, the capital of South Sulawesi province, has been characterised by a competitive form of elite domination. Major political families, most with roots in the ruling elite of the Suharto period, have captured power and used it to further their economic interests while engaging in bitter intra-elite feuds. Through studies of three large-scale coastal reclamation projects, the study reveals patterns of interaction between political elites and business groups in the province. Successive mayors and governors have sponsored rival reclamation projects, directing tenders toward favoured business partners and sidelining allies of rivals. Yet these projects also reveal the limits of power of local politicians: while they support favoured local partners, none has been able to sideline large national conglomerates involved in these projects. Instead, big investors are more or less immune to local political change.