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The effects of boron at concentrations ranging from 5 to 525 ppm in low copper spheroidal graphite iron (SGI) has been studied. At 130 to 140 ppm, no particular effect of boron was observed on the size distributions, number densities, or morphologies of the microparticle populations in the material. Neither was there observed any effects on the size distributions or number densities of graphite nodules. However, boron was observed to lead to a rough surface morphology of the graphite nodules at concentrations as small as 24 ppm. Intercellular carbides were found to form in alloys containing more than 70 ppm boron. Additionally, the graphite shape began to degenerate in alloys with more than 300 ppm of boron. Mass spectrometry analyses revealed these carbides contain relatively high amounts of boron. In an alloy containing 74 ppm boron, it was inferred by using electron backscatter diffraction that these were of the type $${{\hbox {M}}_{23}({\hbox {C}},{\hbox {B}})_{6}}$$ M 23 ( C , B ) 6 borocarbides, where M = Fe, Mn, V, or a combination of them. Mass spectrometry analyses also revealed elevated concentrations of boron in the surface layers of the graphite nodules.

Die 26. Konferenz der Vertragsstaaten des Rahmenübereinkommens der Vereinten Nationen über Klimaänderungen (Conference of the Parties, COP26) fand Anfang November 2021 unter britischem Vorsitz in Glasgow statt. Die COP26 markierte die symbolische Halbzeit zwischen der Verabschiedung der UN-Klimarahmenkonvention (United Nations Framework Convention on Climate Change, UNFCCC) im Jahr 1992 und dem Jahr 2050, wo laut IPCC weltweit netto null CO2-Emissionen erreicht werden müssen. Bis heute steigen die CO2-Emissionen jedoch stetig an. Vor diesem Hintergrund war das Pariser Abkommen (PA) von 2015 ein zentraler Durchbruch. Es ist das erste internationale Abkommen, das von allen Ländern ehrgeizige Klimaschutzmaßnahmen verlangt.

Non-metallic microparticles in spheroidal graphite irons are a product of the inoculation and the Mg-treatment of the liquid melt. Besides the influence on the mechanical properties of these iron–carbon–silicon alloys, they are also responsible for the nucleation and the morphology of the graphite phase. The present investigation is undertaken to study holding time effects of a (Ba, Ca, Al)–ferrosilicon (called Ba-inoculant) and (Ca, Al)–ferrosilicon (called Ca-inoculant) inoculants on the overall distribution of microparticles. Using the 2D to 3D conversions method, which is typically used for graphite nodules, the non-metallic microparticles’ statistical parameters, such as size distributions and number densities, are quantified. The total number of particles is similar after Mg-treatment and inoculation for Ca-inoculant but not for Ba-inoculated samples, which lose approximately 25 pct of microparticles after 1 minute of holding time. Iron treated with the Ca-inoculant loses about 37 pct of its nodules after 5 minutes, while the Ba-inoculated melts maintain their performance even after 10 minutes. Based on extrapolating the trend of the undercooling, Ba-inoculated samples would reach the uninoculated undercooling values in 48 minutes, while Ca-inoculated samples in only 11 minutes. By evaluating the size distributions of the non-metallic microparticles, the Ostwald ripening hypothesis or particle aggregation can be verified. The results suggest that sulfides are more critical for graphite nucleation since they can be correlated with the graphite number densities. However, due to the small difference in the microparticle population of the uninoculated sample with Ca-inoculated samples, other aspects of the fading mechanism need to be considered, such as transient metastable states, since the central hypothesis of loss of inclusions cannot alone explain the decrease in the nucleation frequency of graphite.

Background The risk of destructive wildfire on fire-prone landscapes with excessive fuel buildup has prompted the use of fuel reduction treatments to protect valued resources from wildfire damage. The question of how to maximize the effectiveness of fuel reduction treatments at landscape scales is important because treating an entire landscape may be undesirable or unfeasible. We reviewed 86 simulation studies that examined landscape-scale fuel reduction treatment effectiveness for landscapes of the USA or Canada. Each of these studies tested effects of fuel reduction treatments on wildfire through comparisons of landscape scenarios differing by treatment design or other attributes. Results from these studies were summarized to assess what they reveal about factors determining fuel treatment effectiveness at landscape scales. Results Qualifying studies focused primarily but not exclusively on forested landscapes of the western USA and ranged in size from 200 to 3,400,000 ha. Most studies showed that scenarios with fuel reduction treatments had lower levels of wildfire compared to untreated scenarios. Damaging wildfire types decreased while beneficial wildfire increased as a result of treatments in most cases where these were differentiated. Wildfire outcomes were influenced by five dimensions of treatment design (extent, placement, size, prescription, and timing) and other factors beyond the treatments (weather, climate, fire/fuel attributes, and other management inputs). Studies testing factorial combinations showed that the relative importance of these factors varied across landscapes and contexts. Conclusions Simulation studies have highlighted general principles of effective fuel treatment design at landscape scales, including the desirability of treating extensive areas with appropriate prescriptions at sufficient frequency to reduce wildfire impacts even under extreme conditions that may be more prevalent in the future. More specific, context-dependent strategies have also been provided, such as a variety of placement schemes prioritizing the protection of different resources. Optimization algorithms were shown to be helpful for determining treatment placement and timing to achieve desired objectives under given constraints. Additional work is needed to expand the geographical scope of these studies, further examine the importance and interactions of driving factors, and assess longer-term effects of fuel reduction treatments under projected climate change.

For over 25 years, transmission electron microscopy (TEM) has provided a method for the study of aerosol particles with sizes from below the optical diffraction limit to several microns, resolving the particles as well as smaller features. The wide use of this technique to study aerosol particles has contributed important insights about environmental aerosol particle samples and model atmospheric systems. TEM produces an image that is a 2D projection of aerosol particles that have been impacted onto grids and, through associated techniques and spectroscopies, can contribute additional information such as the determination of elemental composition, crystal structure, and 3D particle structures. Soot, mineral dust, and organic/inorganic particles have all been analyzed using TEM and spectroscopic techniques. TEM, however, has limitations that are important to understand when interpreting data including the ability of the electron beam to damage and thereby change the structure and shape of particles, especially in the case of particles composed of organic compounds and salts. In this paper, we concentrate on the breadth of studies that have used TEM as the primary analysis technique. Another focus is on common issues with TEM and cryogenic-TEM. Insights for new users on best practices for fragile particles, that is, particles that are easily susceptible to damage from the electron beam, with this technique are discussed. Tips for readers on interpreting and evaluating the quality and accuracy of TEM data in the literature are also provided and explained.

Background Ustekinumab (UST) is an approved treatment for adults with inflammatory bowel disease (IBD: Crohn’s disease [CD] and ulcerative colitis [UC]), psoriasis (PsO), and psoriatic arthritis (PsA). Here, we present pooled safety analyses in these approved indications of patients (pts) with active tuberculosis (TB) and opportunistic infections (OIs) through 5 years (yrs) of UST treatment. Methods Pooled data included 13 Phase 2/3 UST studies through 5 yrs of CD and PsO, 2 yrs of UC, and 1 yr of PsA. OIs were identified by clinician review. Herpes zoster (HZ) was evaluated separately. Event rates per 100 pt yrs (PYs) are presented. Concomitant immunomodulators/corticosteroids were permitted in IBD and PsA pts. All pts who received ≥1 UST dose were included. In IBD, placebo (PBO) pts included data up to the first UST dose for pts initially treated with PBO, or >16 weeks after the last UST dose for UST pts who switched to PBO. Results Across all approved indications, 19 OIs including TB were reported, with rates in PBO of 0.40 and UST of 0.10 through 5 yrs in 13807 PYs of follow-up (Table 1); rates of HZ were 1.21 and 0.63, respectively. Of 19 OIs, 18 were in IBD pts and 1 in a PsO pt. Overall, 14/16 pts (12/13 UST) with OIs excluding TB were also receiving confounding concomitant medications. A total of 3 active TB cases (2 pts with CD and 1 pt with UC) were reported in PBO (n=2; 1 in a Hungarian CD pt 10 months after receiving last UST dose) and UST (n=1) pts (Table 1). One active TB case was reported in an asymptomatic South African CD pt treated with UST who had a positive QuantiFERON®-TB Gold test on routine screening and bronchial brushings positive for M. tuberculosis. Both CD pts completed TB treatment with disease resolution. The most common OIs were esophageal candidiasis (UST n=3; PBO n=2) and cytomegalovirus colitis (UST n=3; PBO n=1). Conclusion Rates of OIs, including active TB, in UST-treated pts were low across approved indications through up to 5 yrs with 13807 PYs of follow-up and not higher in UST pts vs PBO pts, suggesting no increased risk of OI with long-term UST treatment.

Background Long-term efficacy of ustekinumab (UST) has been reported in Crohn’s disease (CD) through 5 years (yrs)1 and in ulcerative colitis (UC) through 4 yrs.2 A previous pooled analysis of long-term safety data reported a favorable UST safety treatment profile for inflammatory bowel disease (IBD).3 Here, we present results of the final cumulative analysis of long-term safety data from UST studies through up to 5 yrs in CD and 4 yrs in UC. Methods Data from 6 phase 2/3 UST IBD studies were pooled. In phase 3, patients (pts) received a single IV placebo (PBO) or UST (130mg or ~6mg/kg) induction dose followed by SC maintenance doses of PBO or UST (90mg q8w or q12w). Concomitant immunomodulators and corticosteroids were permitted. All pts who received ≥1 dose of UST were included. Safety outcomes are summarized and presented using number of events per 100 patient-years (PY) of follow-up and corresponding 95% confidence interval (CI). Results In this final pooled UST IBD safety data, 2575 pts were treated with UST with 4826 PYs of follow-up. Rates of key safety events, including MACE and malignancies, were similar between PBO and UST or not higher for UST (Table 1). The most frequently occurring adverse events (AEs) in either group (excluding diseases under study) were headache (PBO 16.66 vs. UST 11.60), arthralgia (PBO 15.91 vs. UST 11.23), abdominal pain (PBO 13.79 vs. UST 9.86), nausea (PBO 11.35 vs. UST 7.13), and pyrexia (PBO 11.35 vs. UST 5.91); infections were nasopharyngitis (PBO 17.82 vs UST 19.10) and upper respiratory tract infection (PBO 11.78 vs UST 9.80). The most frequently reported serious infections of anal abscess, pneumonia, cellulitis, and abdominal abscess were no higher in the UST group than PBO, except gastroenteritis (PBO 0.11 vs UST 0.25). No lymphomas were reported. Nine deaths were reported in UST-treated pts (0.00 [0.00, 0.32] PBO vs. 0.19 [0.09, 0.35] UST), 6 in CD and 3 in UC (all considered unrelated to study agent). Conclusion The final compilation of cumulative UST IBD safety data through 5 yrs in CD and 4 yrs in UC showed a safety profile that continued to be favorable and supports the well-established UST safety experience across all approved indications. References: 1. Sandborn WJ, et al. Five-Year Efficacy and Safety of Ustekinumab Treatment in Crohn's Disease: The IM-UNITI Trial. Clin Gastroenterol Hepatol. 2022;20(3):578-590.e4. 2. Afif W, et al. Efficacy and Safety of Ustekinumab for Ulcerative Colitis Through 4 Years: Final Results from The UNIFI Long-term Extension. UEGW 2023. 3. Sandborn WJ, et al. 129 Safety of Ustekinumab In IBD: Pooled Safety Analysis through 5 years in CD and 2 Years in UC. Gastroenterology. 2021;Supplement:S-35-S-36.

We review the capability of current and scheduled satellite observations of atmospheric methane in the shortwave infrared (SWIR) to quantify methane emissions from the global scale down to point sources. We cover retrieval methods, precision and accuracy requirements, inverse and mass balance methods for inferring emissions, source detection thresholds, and observing system completeness. We classify satellite instruments as area flux mappers and point source imagers, with complementary attributes. Area flux mappers are high-precision ( %) instruments with 0.1–10 km pixel size designed to quantify total methane emissions on regional to global scales. Point source imagers are fine-pixel ( m) instruments designed to quantify individual point sources by imaging of the plumes. Current area flux mappers include GOSAT (2009–present), which provides a high-quality record for interpretation of long-term methane trends, and TROPOMI (2018–present), which provides global continuous daily mapping to quantify emissions on regional scales. These instruments already provide a powerful resource to quantify national methane emissions in support of the Paris Agreement. Current point source imagers include the GHGSat constellation and several hyperspectral and multispectral land imaging sensors (PRISMA, Sentinel-2, Landsat-8/9, WorldView-3), with detection thresholds in the 100–10 000 kg h−1 range that enable monitoring of large point sources. Future area flux mappers, including MethaneSAT, GOSAT-GW, Sentinel-5, GeoCarb, and CO2M, will increase the capability to quantify emissions at high resolution, and the MERLIN lidar will improve observation of the Arctic. The averaging times required by area flux mappers to quantify regional emissions depend on pixel size, retrieval precision, observation density, fraction of successful retrievals, and return times in a way that varies with the spatial resolution desired. A similar interplay applies to point source imagers between detection threshold, spatial coverage, and return time, defining an observing system completeness. Expanding constellations of point source imagers including GHGSat and Carbon Mapper over the coming years will greatly improve observing system completeness for point sources through dense spatial coverage and frequent return times.

Ductile cast iron, also known as nodular cast iron, is a graphite-rich cast iron with high impact and fatigue resistance, due to its nodular graphite inclusions. Ductile cast iron is produced by incorporating additives (often FeSi alloys) to the iron base metal at different production steps to obtain the desired graphite shape. A crucial step is the addition of Magnesium to promote the spheroidization of the graphite. The most common method is by adding crushed and sized Ferro-Silicon-Magnesium (FSM). The alloy composition, microstructure, and sizing are assumed to affect the key parameters of this reaction, namely, reactivity, recovery, and slag formation. Therefore, the study of the solidification of FSM is important to understand and predict its performance at the foundries. The present work aims at understanding and predicting numerically the formation of the major phases during the solidification process. Two approaches have been used: thermodynamic calculations through Thermo-Calc solver and phase field modelling using MICRESS. The models have been calibrated by comparison with advanced statistical characterization of the microstructure. The results indicate a competitive growth of the major phases and transformation of phases in solid state that can be emulated by the model.

Changing wildfire regimes in the western US and other fire-prone regions pose considerable risks to human health and ecosystem function. However, our understanding of wildfire behavior is still limited by a lack of data products that systematically quantify fire spread, behavior and impacts. Here we develop a novel object-based system for tracking the progression of individual fires using 375 m Visible Infrared Imaging Radiometer Suite active fire detections. At each half-daily time step, fire pixels are clustered according to their spatial proximity, and are either appended to an existing active fire object or are assigned to a new object. This automatic system allows us to update the attributes of each fire event, delineate the fire perimeter, and identify the active fire front shortly after satellite data acquisition. Using this system, we mapped the history of California fires during 2012–2020. Our approach and data stream may be useful for calibration and evaluation of fire spread models, estimation of near-real-time wildfire emissions, and as means for prescribing initial conditions in fire forecast models.

According to the National Institute on Drug Abuse (NIDA), more than one hundred people die every day from opioid overdose. Overdose fatalities have risen as the availability of potent synthetic opioids, such as fentanyl, has increased. A forensic postmortem toxicological specimen is often in various stages of decomposition, experiencing autolysis and putrefaction, which complicates the extraction, creating a difficult challenge for toxicologists. Isolating the target drug, while creating an efficient and simplified analytical scheme, is a goal for most toxicology laboratories. The validation of a quick, easy, cheap, effective, rugged and safe extraction protocol is presented in this study as an alternative analytical method for efficient extraction and detection of fentanyl and its major metabolites: norfentanyl and despropionyl fentanyl (4-ANPP). The liquid Chromatography with tandem mass spectrometry analysis was validated following the American Academy of Forensic Sciences Standards Board (ASB) standard 036 proposed requirements. Evaluated parameters include selectivity, matrix effects (MEs), linearity, processed sample stability, bias, precision and proof of applicability using liver samples from authentic postmortem cases. MEs (represented as percent ionization suppression or enhancement) at low and high concentrations were −10.0% and 1.4% for fentanyl, −2.1% and −0.3% for 4-ANPP and 3.1% and 2.8% for norfentanyl, respectively. Bias for the three analytes ranged from −8.5% to −19.9% for the low concentrations, −3.6% to −14.7% for the medium concentrations and 1.5% to −16.1% for the high concentrations with all being within the ±20% guideline. Precision for the three analytes ranged from 2.2% to 15.1%. The linear range for the fentanyl and norfentanyl was 0.5–100 and 4-ANPP had a linear range of 0.4–80 μg/kg. The authentic postmortem liver samples ranged in fentanyl concentrations from 56.6 to 462.3 μg/kg with a mean of 149.2 μg/kg (n = 10). The range of norfentanyl concentrations were 1.9 to 50.0 μg/kg with a mean of 14.1 μg/kg (n = 10). The range of 4-ANPP concentrations were 3.2 to 23.7 μg/kg with a mean of 7.5 μg/kg (n = 7).

Objective: The biomedical/behavioral sciences lag in the recruitment and ad­vancement of students from historically underrepresented backgrounds. In 2014 the NIH created the Diversity Program Consortium (DPC), a prospective, multi-site study comprising 10 Building Infrastructure Leading to Diversity (BUILD) institutional grantees, the National Research Mentor­ing Network (NRMN) and a Coordination and Evaluation Center (CEC). This article describes baseline characteristics of four incoming, first-year student cohorts at the primary BUILD institutions who completed the Higher Education Research Institute, The Freshmen Survey between 2015-2019. These freshmen are the primary student cohorts for longitudinal analyses comparing outcomes of BUILD program participants and non-participants. Design: Baseline description of first-year students entering college at BUILD institu­tions during 2015-2019. Setting: Ten colleges/universities that each received

The increasing demand for rapid methods to identify both inorganic and organic gunshot residues (IGSR and OGSR) makes electrochemical methods, an attractive screening tool to modernize current practice. Our research group has previously demonstrated that electrochemical screening of GSR samples delivers a simple, inexpensive, and sensitive analytical solution that is capable of detecting IGSR and OGSR in less than 10 min per sample. In this study, we expand our previous work by increasing the number of GSR markers and applying machine learning classifiers to the interpretation of a larger population data set. Utilizing bare screen-printed carbon electrodes, the detection and resolution of seven markers (IGSR; lead, antimony, and copper, and OGSR; nitroglycerin, 2,4-dinitrotoluene, diphenylamine, and ethyl centralite) was achieved with limits of detection (LODs) below 1 µg/mL. A large population data set was obtained from 395 authentic shooter samples and 350 background samples. Various statistical methods and machine learning algorithms, including critical thresholds (CT), naïve Bayes (NB), logistic regression (LR), and neural networks (NN), were utilized to calculate the performance and error rates. Neural networks proved to be the best predictor when assessing the dichotomous question of detection of GSR on the hands of shooter versus nonshooter groups. Accuracies for the studied population were 81.8 % (CT), 88.1% (NB), 94.7% (LR), and 95.4% (NN), respectively. The ability to detect both IGSR and OGSR simultaneously provides a selective testing platform for gunshot residues that can provide a powerful field-testing technique and assist with decisions in case management.

Research Summary Strategy formation is central to why some firms seize novel opportunities while others fail. We explore a core dilemma of strategy formation in entrepreneurial settings—whether to learn a novel strategy one domain at a time (modular) versus assemble a complex strategy of coherent activities across all domains at once (integrative). By studying six ventures, we develop a theoretical framework for how entrepreneurs effectively form novel, complex strategy: Decision weaving. They (a) employ sequential focus (not parallel), (b) pause at plateaus (not optima), and (c) deploy stepping stones (not leaps) in background domains. These behaviors enable both fast, effective learning and evolving yet holistic understanding of an emerging strategy. Overall, we contribute to the microfoundations of strategy by proposing a cognitively sophisticated, yet realistic strategist. Managerial Summary Strategy formation is central to why firms seize novel opportunities while others fail. By comparing three venture‐pairs, we develop a fresh framework for strategy formation in nascent markets where strategy is both novel and complex: Decision weaving. Effective strategists: (a) use sequential focus (not parallel) to learn about successive focal strategic domains, (b) pause at learning plateaus to consolidate that knowledge about a focal domain, and (c) use stepping stones to make progress in background domains without losing focus. These behaviors enable both fast, effective learning, and evolving yet holistic understanding of an emerging strategy. More importantly, these behaviors set the stage for rapid and profitable scaling (i.e., growth).

Last year's conference of the global climate change regime took place from 2 until 15 December 2019 in Madrid, Spain. Despite marking a new record for overtime in the history of the UNFCCC, the conference did not only fail to meet the increasing public demand for swift and strong climate action, it also failed on its formal mandate to finalise the Paris rulebook. A record number of issues were left unresolved and shelved for the next session. COP25 thereby highlighted how much work still lies ahead both domestically and internationally if 2020 is to see a step-up in climate action that is consistent with the long-term goal of the Paris Agreement.