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The Haber–Bosch process is a cornerstone in the field of ammonia production and represents a decisive advance in industrial chemistry. This method, developed in the early 20th century, revolutionizes agriculture and enables the mass production of fertilizers. As the world strives for sustainable energy and environmental protection, alternative methods such as the photo/photoelectrocatalytic nitrogen reduction reaction (NRR) are gaining momentum. By using sunlight, electricity, or a combination of both, these approaches promise sustainable ammonia production with renewable energy sources and innovative materials. Researchers are trying to understand the underlying principles, mechanisms, and advances of these methods to overcome the challenges and optimize their effectiveness. This research is a step toward sustainable energy and agriculture, and offers a greener and more efficient way forward. This review looks at advances in sustainable ammonia production, particularly through photo‐ and photoelectrocatalytic NRRs. It examines the hurdles in implementing these methods and provides an overview of the fundamentals of nitrogen fixation and a comparison of current mechanisms. In addition, thermodynamic, theoretical, and computational studies of these processes are summarized. Various photocatalysts and photoelectrocatalysts used for ammonia production are also presented.

The article discusses the production of platform chemicals from various biological sources, including glycerol, lignin, cellulose, bio-oils, and sea products. It presents the results of catalytic and downstream processes involved in the conversion of these biomass-derived feedstocks. The experimental approaches are complemented by numerical descriptions, ranging from density functional theory (DFT) calculations to kinetic modellingof the experimental data. This multi-scale modelling approach helps to understand the underlying mechanisms and optimize the production of platform chemicals from renewable resources.

Summary:. Clinical trials (CTs) are crucial for evidence-based surgical care. Despite growing interest in plastic and reconstructive surgery (PRS) research, the status of PRS CTs remains unknown. We obtained PRS CTs from ClinicalTrials.gov and WHO’s International Clinical Trials Registry Platform (November 2022). Topic modeling identified research themes and machine learning models generated CT-publication pairs. Kaplan-Meier curves visualized CT discontinuation and nonpublication. Of the 4685 PRS CTs identified, 79% were interventional and 81% recruited adults. Most were single-center-led (67%) and academic-funded (77%). Male investigators led 77% of CTs. Female-only patient CTs outnumbered male-only (31% versus 1%). The United States led with 41% of CTs, followed by France, Canada, and China. Industry-funded CTs were higher in the USA, Germany, and Belgium, and academic-funded in France, Canada, and China. PRS CTs clustered into aesthetics (43%), reconstructive (20%), wound healing (8%), peripheral nerve (6%), tumor excision (5%), craniofacial (5%), perioperative pain (5%), and burns (4%). Industry preferred funding aesthetics, whereas academia and industry co-funded wound healing. Publication rates of completed (24%) and terminated (10%) CTs varied by cluster, with perioperative pain CTs exhibiting higher rates. Industry-funded CTs had lower publication rates (hazard ratio: 0.64, 95% confidence interval: 0.5–0.81) and higher discontinuation (hazard ratio: 1.34, confidence interval: 1.06–1.68) driven by sponsors’ decision to terminate prematurely. Global growth in PRS trialome reflects rising interest in evidence-based plastic surgery. Yet, imbalances in participant age, geography, funding source, and trial design influence likelihood of CT discontinuation and publication. Key research gaps include pediatric CTs, accountability in industry-funded research, and multicenter collaborations with underrepresented regions.

In 2016, the U.S. Food and Drug Administration (FDA), the Centers for Disease Control and Prevention (CDC), and state partners investigated nine Listeria monocytogenes infections linked to frozen vegetables. The investigation began with two environmental L. monocytogenes isolates recovered from Manufacturer A, primarily a processor of frozen onions, that were a match by whole genome sequencing (WGS) to eight clinical isolates and historical onion isolates with limited collection details. Epidemiologic information, product distribution, and laboratory evidence linked suspect food items, including products sourced from Manufacturer B, also a manufacturer of frozen vegetable/fruit products, with an additional illness. The environmental isolates were obtained during investigations at Manufacturers A and B. State and federal partners interviewed ill people, analyzed shopper card data, and collected household and retail samples. Nine ill persons between 2013 and 2016 were reported in four states. Of four ill people with information available, frozen vegetable consumption was reported by three, with shopper cards confirming purchases of Manufacturer B brands. Two identified outbreak strains of L. monocytogenes (Outbreak Strain 1 and Outbreak Strain 2) were a match to environmental isolates from Manufacturer A and/or isolates from frozen vegetables recovered from open and unopened product samples sourced from Manufacturer B; the investigation resulted in extensive voluntary recalls. The close genetic relationship between isolates helped investigators determine the source of the outbreak and take steps to protect public health. This is the first known multistate outbreak of listeriosis in the United States linked to frozen vegetables and highlights the significance of sampling and WGS analyses when there is limited epidemiologic information. Additionally, this investigation emphasizes the need for further research regarding food safety risks associated with frozen foods.

Background:. Plastic surgeons are frequently consulted to perform temporal artery biopsy (TAB), even though patients meet the American College of Rheumatology diagnostic criteria for giant cell arteritis (GCA) and are already treated. This study aimed to analyze the impact of TAB on steroid duration in patients undergoing TAB. Methods:. We undertook a prospective study of adult patients undergoing TAB for GCA in Calgary. Consecutive, multicenter recruitment was performed over 2 years. Primary outcomes included initiation or discontinuation and duration of corticosteroids. Results:. Twenty-one TABs were performed in 20 patients. Nineteen percent of TABs were positive, and 71.4%, negative. In 9.5% of patients, accidental sampling of a vessel other than the superficial temporal artery occurred. Fifty-two percent of patients received steroids before TAB, of which the mean duration was 8.0 days for TAB+ (postive temporal artery biopsy result) patients and 8.4 days for TAB− (negative temporal artery biopsy result; P = 0.22) patients. Before TAB, the American College of Rheumatology score was 2.5 for TAB+ patients and 2.4 for TAB− (P = 0.74). Postbiopsy, the American College of Rheumatology score was 3.5 for TAB+ patients (therefore reaching diagnostic threshold of 3) but remained 2.4 for TAB− (P = 0.02). TAB+ patients were treated for 352.3 days, whereas TAB− patients for 16.7 days (P = 0.29). Complications were more likely with long-term (>6 weeks) steroids (P = 0.17). Conclusion:. In patients with a low suspicion of GCA, a negative TAB helps bolster physician confidence and leads to a shorter steroid duration.

Background:. Temporal artery biopsy (TAB) in diagnosing giant cell arteritis has been criticized due to surgical risks, a high false negative rate, and redundant information when patients already met American College of Rheumatology criteria. The objective of this study was to investigate TAB's impact on steroid treatment duration. Methods:. A retrospective chart review garnered patient demographics, symptoms, comorbidities, and steroid treatment duration in patients undergoing TAB at a single center. Steroid treatment was compared between TAB+ and TAB - patients. Results:. One hundred seven patients undergoing TAB were included. Patients were predominantly women (70.1%) with a median age of 74 years (46 -91). Of 107 TAB results, 74 (69.2%) were negative, 23 (21.5%) were positive, and 10 (9.3%) were found to be indeterminate. In TAB+ patients, the mean erythrocyte sedimentation rate was not significantly different than TAB - patients (60.2 versus 43.7, P = 0.45), nor was the median C-reactive protein (38.8 versus 18.1, P = 0.17). Regarding steroid use, both TAB+ and TAB - patients had a similarly high rate of prebiopsy steroid initiation (82.6% versus 70.3%, P = 0.32). More TAB+ patients remained on steroids at 6 weeks (95.0% versus 57.4%, P = 0.004), 6 months (95% versus 37.7%, P < 0.001), 1 year (65.0% versus 31.1%, P = 0.024), and 18 months (50.0% versus 19.7%, P = 0.045). By 2 years, the difference no longer met significance (35.0% versus 14.8%, P = 0.12). P = 0.12). Conclusion:. TAB positivity does seem to influence maintenance of steroids up to 18 months after biopsy.

Background:. Temporal artery biopsy (TAB) is currently the gold standard procedure to diagnose giant cell arteritis. Despite low sensitivity, TAB is routinely performed even if a clinical diagnosis has already been made. The objective of this study was to determine the usefulness of TAB for giant cell arteritis management. Methods:. We performed a systematic review to identify studies that compared steroid treatment between TAB+ and TAB− patients. EMBASE, MEDLINE, and the Cochrane Central Register of Controlled Trials were searched from inception until April 4, 2020. Titles, abstracts, and full texts were reviewed by two independent reviewers and conflicts resolved by consensus. Studies reporting TAB result and steroid treatment were included. Information pertaining to steroid treatment was compared between TAB+ and TAB− groups. Steroid duration was compared by grouping patients in a less than 6 month group, a 6–24 month group, and a more than 24 month group. Results:. An estimated 5288 abstracts were screened and 13 studies involving 1355 patients were included. Rate of prebiopsy steroid treatment was higher in TAB+ patients compared with TAB− patients [93% versus 63% (P < 0.001)]. The TAB+ group was more likely to be started on steroids prebiopsy [28% versus 8% (P < 0.001)]. TAB+ and TAB− patients had similar steroid duration for all groups [24-month group 66% versus 63% (P-0.642)]. Conclusion:. TAB results have minimal impact on treatment, and the utility should be reconsidered when a clinical diagnosis of giant cell arteritis is possible.

BackgroundThe identification of an appropriate rhythm management strategy for patients diagnosed with atrial fibrillation (AF) remains a major challenge for providers. Although clinical trials have identified subgroups of patients in whom a rate- or rhythm-control strategy might be indicated to improve outcomes, the wide range of presentations and risk factors among patients presenting with AF makes such approaches challenging. The strength of electronic health records is the ability to build in logic to guide management decisions, such that the system can automatically identify patients in whom a rhythm-control strategy is more likely and can promote efficient referrals to specialists. However, like any clinical decision support tool, there is a balance between interpretability and accurate prediction. ObjectiveThis study aims to create an electronic health record–based prediction tool to guide patient referral to specialists for rhythm-control management by comparing different machine learning algorithms. MethodsWe compared machine learning models of increasing complexity and used up to 50,845 variables to predict the rhythm-control strategy in 42,022 patients within the University of Colorado Health system at the time of AF diagnosis. Models were evaluated on the basis of their classification accuracy, defined by the F1 score and other metrics, and interpretability, captured by inspection of the relative importance of each predictor. ResultsWe found that age was by far the strongest single predictor of a rhythm-control strategy but that greater accuracy could be achieved with more complex models incorporating neural networks and more predictors for each participant. We determined that the impact of better prediction models was notable primarily in the rate of inappropriate referrals for rhythm-control, in which more complex models provided an average of 20% fewer inappropriate referrals than simpler, more interpretable models. ConclusionsWe conclude that any health care system seeking to incorporate algorithms to guide rhythm management for patients with AF will need to address this trade-off between prediction accuracy and model interpretability.

Background:. Temporal artery biopsies (TAB) rarely impact management of patients with suspected giant cell arteritis and carry complications. We sought plastic surgeons’ perspectives on this procedure’s risks and benefits. Methods:. An email survey was designed, piloted, and refined to elicit Canadian Society of Plastic Surgeons (CSPS) members about TAB’s diagnostic contribution, complications, usefulness as a resident education tool, and surgeons’ insight into emerging diagnostic modalities like ultrasound. Text comments were sought at each question. A reminder was emailed one week later. Data was compared and analyzed using the chi-squared test and student t-test. Results:. An estimated 83 responses were received from 435 surgeons (19%). Of the surgeons, 20% voiced uncertainty regarding TAB indications; 40% were unsure if TAB results changed steroid duration and dose; 83% did not see patients postoperatively. Surgeons recalled 29 cases of hematoma and three facial nerve injuries from TAB. In total, 80% felt TAB was a valuable learning opportunity for residents, although residents were involved in only 21% of cases; 65% of surgeons supported a changeover to ultrasound as primary diagnostic modality. Analysis of text comments revealed a sense of futility from TAB and disdain toward being mere technicians. Several participants wished for stakeholders to collaborate and potentially endorse noninvasive diagnostic modalities. Conclusions:. This survey demonstrated varying attitudes to TAB. Generally, plastic surgeons were uncertain of TAB’s contribution to treatment, tended not to follow-up on results or patients, and recognized a number of complications. Conversations are desired regarding switching from scalpel to probe to evaluate the temporal artery.

This paper describes a recent study on using fly ash for backfilling abandoned room and pillar mines. Detailed investigations on fly ash properties such as the strength and stiffness of settled fly ash, flowability of fly ash grout, as well as chemistry and environmental aspects of fly ash backfill have been undertaken in the laboratory. Numerical modelling was also conducted to quantify the effects of fly ash backfill on the stability of underground pillars. The laboratory tests showed that with a solid concentration of approximate 50%, fly ash grout has an excellent flowability and very low viscosity. It is capable of penetrating and filling almost any voids underground if designed properly and settling as a reasonably stiff solid to provide support to the pillars. Several different types of strength tests proved that a consolidated fly ash should exhibit a friction angle above 42°. 3D numerical modelling on interaction between fly ash backfill and underground pillars has shown that fly ash backfill to 90% roadway height can raise the factor of safety (FoS) of a marginally stable area to above 1.6, which is the number often used in rock engineering design for long term stability. Chemistry and leachate analysis of representative fly ash samples from a local power station showed that the elemental concentrations in the fly ash solid sample are lower than the allowed contaminant threshold and specific contaminant concentration levels. Geotechnical monitoring in the high risk areas of an abandoned mine has been carried out as part of the risk management and control for potential subsidence. The monitoring has been very helpful in understanding the ground behaviour around the abandoned mine which can provide timely information to the parties concerned in order to make correct decisions to control the subsidence risk. Keywords: Abandoned mine, Backfill, Fly ash, Laboratory tests, Monitoring, Modelling

This paper presents a new dynamic environmental risk model, with intended use within a new, dynamical approach for risk based ship traffic prioritisation. The philosophy behind this newly developed approach is that shipping risk can be reduced by directing efforts towards ships and areas that have been identified as high priority (high risk), prior to a potential accident. The risk model proposed in this paper separates itself from previous models by drawing on available information on dynamic factors and by focusing on the ship's surroundings. The model estimates the environmental risk of drift grounding accidents for oil tankers in real time and in forecast mode, combining the probability of grounding with oil spill impact on the coastline. Results show that the inherent dynamic risk introduced by an oil tanker sailing along the North Norwegian coast depends, not surprisingly, significantly upon wind and ocean currents, as well as tug position and cargo oil type. Results of this study indicate that the risk model is well suited for real time risk assessment, and effectively separates low risk and high risk situations. The model is well suited as a tool to prioritise oil tankers and coastal segments. This enables dynamic risk based positioning of tugs, using both real-time and projected risk, for effective support in case of a drifting ship situation.

The paper describes a model, which estimates the risk levels of individual crude oil tankers. The intended use of the model, which is ready for trial implementation at The Norwegian Coastal Administrations new Vardø VTS (Vessel Traffic Service) centre, is to facilitate the comparison of ships and to support a risk based decision on which ships to focus attention on. For a VTS operator, tasked with monitoring hundreds of ships, this is a valuable decision support tool. The model answers the question, "Which ships are likely to produce an oil spill accident, and how much is it likely to spill?".