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This book gives a non-technical overview of robust data reduction techniques, encouraging the use of these important and useful methods in practical applications. The main areas covered include principal components analysis, sparse principal component analysis, canonical correlation analysis, factor analysis, clustering, double clustering, and discriminant analysis. Using real examples, the authors show how to implement the procedures in R. The code and data for the examples are available on the book's CRC Press web page.

Photo-reduction of O2 to water mediated by flavodiiron proteins (FDPs) represents a safety valve for the photosynthetic electron transport chain in fluctuating light. So far, the FDPmediated O2 photo-reduction has been evidenced only in cyanobacteria and the moss Physcomitrella; however, a recent phylogenetic analysis of transcriptomes of photosynthetic organisms has also revealed the presence of FDP genes in several nonflowering plant groups. What remains to be clarified is whether the FDP-dependent O2 photo-reduction is actually operational in these organisms. We have established a simple method for the monitoring of FDP-mediated O2 photoreduction, based on the measurement of redox kinetics of P700 (the electron donor of photosystem I) upon dark-to-light transition. The O2 photo-reduction is manifested as a fast reoxidation of P700. The validity of the method was verified by experiments with transgenic organisms, namely FDP knock-out mutants of Synechocystis and Physcomitrella and transgenic Arabidopsis plants expressing FDPs from Physcomitrella. We observed the fast P700 re-oxidation in representatives of all green plant groups excluding angiosperms. Our results provide strong evidence that the FDP-mediated O2 photo-reduction is functional in all nonflowering green plant groups. This finding suggests a major change in the strategy of photosynthetic regulation during the evolution of angiosperms.

HighlightsThe advancement and current status of dual-atom catalysts are reported.The synergistic effects exhibited by recent dual-atom catalysts in mechanistic studies are classified and summarized.Challenges and prospects of dual-atom catalysts in synthesis, characterization, applications, and theory are discussed.The exploration of sustainable energy utilization requires the implementation of advanced electrochemical devices for efficient energy conversion and storage, which are enabled by the usage of cost-effective, high-performance electrocatalysts. Currently, heterogeneous atomically dispersed catalysts are considered as potential candidates for a wide range of applications. Compared to conventional catalysts, atomically dispersed metal atoms in carbon-based catalysts have more unsaturated coordination sites, quantum size effect, and strong metal–support interactions, resulting in exceptional catalytic activity. Of these, dual-atomic catalysts (DACs) have attracted extensive attention due to the additional synergistic effect between two adjacent metal atoms. DACs have the advantages of full active site exposure, high selectivity, theoretical 100% atom utilization, and the ability to break the scaling relationship of adsorption free energy on active sites. In this review, we summarize recent research advancement of DACs, which includes (1) the comprehensive understanding of the synergy between atomic pairs; (2) the synthesis of DACs; (3) characterization methods, especially aberration-corrected scanning transmission electron microscopy and synchrotron spectroscopy; and (4) electrochemical energy-related applications. The last part focuses on great potential for the electrochemical catalysis of energy-related small molecules, such as oxygen reduction reaction, CO2 reduction reaction, hydrogen evolution reaction, and N2 reduction reaction. The future research challenges and opportunities are also raised in prospective section.

We prove the existence of an almost full measure set of The proof exploits nice parity properties of a new set of coordinates for the planetary problem, which reduces completely the number of degrees of freedom for the system (in particular, its degeneracy due to rotations) and, moreover, is well fitted to its reflection invariance. It allows the explicit construction of an associated close to be integrable system, replacing Birkhoff normal form, common tool of previous literature.

Background In elderly tibial plateau fractures (TPFs), the lateral condyles are involved frequently. This study aimed to compare the outcomes of open reduction and internal fixation (ORIF) and double reverse traction repositor (DRTR) assisted closed reduction and internal fixation (CRIF) in elderly patients with lateral TPFs. Methods From January 2015 to July 2020, we retrospectively reviewed 68 patients treated surgically at our trauma center for lateral TPFs (Schatzker type I-III). 31 patients were eventually assigned to the DRTR assisted CRIF group, whereas 37 patients were assigned to the ORIF group. The primary outcomes included surgical details, radiological assessment, follow-up knee function, and complications. Results The DRTR assisted CRIF group experienced a 43.6 mL decrease in intraoperative blood loss (161.3 ml vs 204.9 ml, p  = 0.033), and the operation duration was 32.1 min shorter than the ORIF group (83.8 min vs 115.9 min, p  < 0.001). There was no statistically significant difference in terms of widening of the tibia plateau (WTP), depth of articular depression (DAD), medial proximal tibial angle (MPTA) and posterior tibial slope angle (PTSA) immediately after surgery and at the last follow-up. No differences in malreduction ( p  = 0.566) or reduction loss ( p  = 0.623) were observed between the groups, and Lysholm and HSS scores were similar between the two groups (83.6 ± 15.8 vs 83.4 ± 5.1, p  = 0.934; 89.3 ± 7.8 vs 86.9 ± 6.2, p = 0.172; respectively). However, ORIF was associated with a greater increase in postoperative complications than DRTR assisted CRIF (3.2% vs 27%, p  = 0.008). Conclusion Both types of internal fixation provide good radiological outcomes and knee function in the treatment of lateral TPFs in the elderly. However, DRTR assisted CRIF has the advantage of a shorter duration of surgery, less blood loss, and fewer postoperative complications, and appears to be a better treatment option for elderly patients with lateral TPFs.

HighlightsThe latest advancements in Cu-based catalysts for photocatalytic and electrocatalytic CO2 reduction into C2+ products are reported.The relationship between the Cu surfaces and their efficiency in photocatalytic and electrocatalytic CO2 reduction is emphasized.The opportunities and challenges associated with Cu-based materials in the CO2 catalytic reduction applications are presented.Carbon dioxide conversion into valuable products using photocatalysis and electrocatalysis is an effective approach to mitigate global environmental issues and the energy shortages. Among the materials utilized for catalytic reduction of CO2, Cu-based materials are highly advantageous owing to their widespread availability, cost-effectiveness, and environmental sustainability. Furthermore, Cu-based materials demonstrate interesting abilities in the adsorption and activation of carbon dioxide, allowing the formation of C2+ compounds through C–C coupling process. Herein, the basic principles of photocatalytic CO2 reduction reactions (PCO2RR) and electrocatalytic CO2 reduction reaction (ECO2RR) and the pathways for the generation C2+ products are introduced. This review categorizes Cu-based materials into different groups including Cu metal, Cu oxides, Cu alloys, and Cu SACs, Cu heterojunctions based on their catalytic applications. The relationship between the Cu surfaces and their efficiency in both PCO2RR and ECO2RR is emphasized. Through a review of recent studies on PCO2RR and ECO2RR using Cu-based catalysts, the focus is on understanding the underlying reasons for the enhanced selectivity toward C2+ products. Finally, the opportunities and challenges associated with Cu-based materials in the CO2 catalytic reduction applications are presented, along with research directions that can guide for the design of highly active and selective Cu-based materials for CO2 reduction processes in the future.

There have been ever‐growing demands to develop advanced electrocatalysts for renewable energy conversion over the past decade. As a promising platform for advanced electrocatalysts, reduced graphene oxide (rGO) has attracted substantial research interests in a variety of electrochemical energy conversion reactions. Its versatile utility is mainly attributed to unique physical and chemical properties, such as high specific surface area, tunable electronic structure, and the feasibility of structural modification and functionalization. Here, a comprehensive discussion is provided upon recent advances in the material preparation, characterization, and the catalytic activity of rGO‐based electrocatalysts for various electrochemical energy conversion reactions (water splitting, CO2 reduction reaction, N2 reduction reaction, and O2 reduction reaction). Major advantages of rGO and the related challenges for enhancing their catalytic performance are addressed. As a promising platform for advanced electrocatalysts, reduced graphene oxide (rGO) has attracted substantial research interests in a variety of electrochemical energy conversion reactions. The rGO platform plays versatile roles thanks to their unique physical and chemical properties, such as high‐specific surface area, tunable electronic structure, and the feasibility of structural modification and functionalization.

Nanotechnology is a new and emerging technology with wealth of applications. It involves the synthesis and application of materials having one of the dimensions in the range of 1–100 nm. A wide variety of physico–chemical approaches are being used these days for the synthesis of nanoparticles (NPs). However, biogenic reduction of metal precursors to produce corresponding NPs is eco-friendly, less expensive, free of chemical contaminants for medical and biological applications where purity of NPs is of major concern. Biogenic reduction is a “Bottom Up” approach similar to chemical reduction where a reducing agent is replaced by extract of a natural products with inherent stabilizing, growth terminating and capping properties. Furthermore, the nature of biological entities in different concentrations in combination with reducing organic agents influence the size and shape of NPs. Present review focuses on microbes or plants based green synthesis of Ag, Au, Cu, Fe, Pd, Ru, PbS, CdS, CuO, CeO₂, Fe₃O₄, TiO₂, and ZnO NPs and their potential applications.

A novel experimental setup for simultaneous weight, surface temperature, and center temperature tracking of a single iron ore pellet under reducing conditions has been utilized. Studies conducted in the setup indicate that the reduction of iron ore pellets in a pure hydrogen atmosphere is controlled by several transport steps inside the pellet. It is further shown that for a period of time during reduction, the reduction rate is limited by the heat transfer inside the sample. Any attempt to make accurate and robust models of the hydrogen based iron ore reduction process must therefore consider heat transfer in the pellet. The reduction is observed to take place in a reduction zone extending along the pellet radius, consisting of a mix of different phases. The amount of the different phases varies with radial position and time, as does the observed temperature gradient between the surface and the center of the pellet. Representative literature data on actual transfer coefficients of this system is therefore not available. Apparent thermal conductivities for the different experimental temperatures are evaluated based on the experimental data and found to be significantly lower than the corresponding value for dense iron.

This paper presents a comparison of traditional thermal and chemical reduction methods with more recent ionizing radiation reduction via gamma rays and electron beams (e-beams). For GO, all synthesis protocols were adapted to increase production scale and are a contribution of this work. The typical Raman D-band of the GO was prominent (ID/IG ratio increased sixfold). When comparing the GO reduction techniques, dramatic differences in efficiency and GO particle characteristics were observed. Although thermal and chemical reduction are effective reduction methods, as shown through the use of FTIR spectroscopy and the C/O ratio from EDS chemical analysis, the thermal process renders great weight losses, whereas chemical processing may involve the use of hazardous chemical compounds. On the other hand, comparing the gamma rays and e-beam for 80 kGy, the Raman spectra and chemical analysis suggested that the e-beam caused a greater GO reduction: C/O ratio from EDS of 5.4 and 4.1, respectively. In addition to being fast and effective, ionizing radiation reduction processes allow easier control of the reduction degree by adjusting the radiation dose. When the dose increased from 40 to 80 kGy, the Raman spectra and EDS showed that the ID/IG and C/O ratios increased by 15 and 116%, respectively.