bluuebunny/crossref_metadata_2025 huggingface dataset:
Pd‐Catalyzed CChalcogen Bond Formation (CS, CSe) by CH Bond Activation
Authors: Vuagnat Martin , Jubault Philippe , Besset Tatiana
Published: September 2022

Organosulfur and organoselenium compounds are indisputable key compounds in material science, agrochemical and pharmaceutical industries. Therefore, the quest for efficient methodologies to access sulfur‐ and selenium‐containing molecules has aroused the interest of the scientific community. In the past decade, transition metal‐catalyzed CH bond activation appeared to be a powerful and more sustainable tool to reach high molecular complexity from non‐pre‐functionalized substrates. This article summarizes the recent advances that have been made in the field of the palladium‐catalyzed CS/CSe bond formation by CH bond activation.
Ruthenium‐Catalyzed Remote CH Functionalization of Directed Arenes
Authors: Yan Yuting , Fu Xuegang , Huang Jianhui
Published: September 2022

In arene chemistry, CH direct functionalization has become one of the most attractive and challenge strategies for the introduction of new fragments bringing molecular complexity. Among a great number of transition metals involved in reaction approaches, Ru‐catalyzed CH functionalization of directed aryl‐containing compounds certainly provided unique reaction modes and new synthetic consideration in molecular design. In this article, we have overviewed the recent advances in the development of new synthetic approaches within the field of Ru‐catalyzed remote CH functionalization of directed arenes. The developments of the methodologies, synthetic applications, and reaction mechanisms on typical reaction modes have been discussed, and examples for accessing molecules in medicinal chemistry were also included.
Iron‐Catalyzed CH Functionalization to Form CC and C–Heteroatom Bonds
Authors: Mondal Susmita , Samanta Sadhanendu , Hajra Alakananda
Published: September 2022

The direct functionalization of CH bonds for the construction of CC and C–heteroatom bonds is an attractive research tool for the synthetic organic community. In this regard, iron‐catalyzed CH functionalization has received significant attention due to its wide redox potential range, natural abundance, multiple oxidation states, low toxicity, sustainable nature, and low cost. Herein, we have highlighted Fe‐catalyzed CC and C–heteroatom bond‐forming reactions and their potential application in the synthesis of heterocycles and bioactive natural products.
Ni, Rh, and Fe‐Catalyzed CH Functionalization by Electrochemistry
Authors: Yaqoob Aaron , Xing Yalan
Published: September 2022

In the past decades, transition metal‐catalyzed CH activation reactions have developed into a powerful tool in organic synthesis due to their effectiveness of direct conversion of simple and ubiquitous CH bonds into diverse functional groups. Recently, organic electrochemistry has experienced a remarkable renaissance and emerged from an underappreciated technique into an attractive method in the synthetic organic chemistry community. Therefore, the combination of metal‐catalyzed CH activation with electrochemistry offers exciting opportunities which conventional chemistry may not be able to achieve for the development of highly chemo‐, regio‐, and stereoselective synthetic methodologies. In this article, we will be focusing on cutting‐edge and novel transformations enabled by Ni, Rh, and Fe‐catalyzed CH activations with electrochemistry.
Visible‐Light Mediated CH Functionalization of Heteroarenes
Authors: Ganie Majid Ahmad , Bhat Muneer Ul Shafi , Kumar Sourav , Shah Bhahwal Ali
Published: September 2022

The ability of photoredox catalyzed reactions to reroute the conventional transition metal‐catalyzed CH functionalization reactions via alternative radical‐mediated pathways with improved step and atom economies has revolutionized the field of organic synthesis. These transformations proceed with atypical reaction pathway, wherein the photo‐catalyst upon photo‐excitation engages with the organic substrate in single electron transfer (SET) to generate open‐shell species which undergoes regio‐selective addition resulting in the formation of carbon–carbon or carbon–heteroatom bonds. Compared to transition metal catalysis, photoredox catalyzed approaches offer distinct advantages in terms of operational ease, practicability, and providing access to various elusive reaction pathways under mild conditions. The present article gives an account of the recent developments in visible light‐mediated CH functionalization of heteroarenes.
Adaptive fuzzy practical fixed‐time control for uncertain nonlinear systems with actuator constraints
Authors: You Guodong , Xu Bin , Cao Yang , Hou Xiaoxin , Zhao Shuangle
Published: September 2022

This article addresses an adaptive fuzzy practical fixed‐time tracking control for nonlinear systems with unknown actuator constraints and uncertainty functions. First, fuzzy logic systems (FLSs) are used to identify uncertain functions. Then, by utilizing FLSs, backstepping technique, and finite‐time stability theory, an adaptive fuzzy practical fixed‐time control is proposed to obtain satisfactory tracking performance even when the actuator faults. The theoretical analysis verified that the closed‐loop systems is practical fixed‐time stable under the proposed control strategy, the tracking error converges to a small neighborhood of the origin in a fixed time, and the convergence time is independent of the state conditions. Finally, both numerical simulation and physical example demonstrates the effectiveness of the proposed control strategy.
Structure elucidation of a bimetallic μ‐hydroxo‐bridged Cu(II)‐flufenamate‐bpy complex and cytotoxic evaluation against MDA‐MB‐231 and A549 carcinoma cell lines
Authors: Yousuf Imtiyaz , Mantoo Imtiyaz Ahmad , Bashir Masrat , Bhat Shahnawaz Ali
Published: September 2022

In this work, we report the synthesis, spectral characterization, and in vitro biological assessment of a bimetallic copper complex with formulation [Cu2(fluf)3(bpy)2(μ‐OH)(H2O)] (complex 1) as a potential chemotherapeutic agent. The structural elucidation of synthesized complex was ascertained by various spectroscopic methods, namely, UV–vis, Fourier transform infrared (FTIR), electron paramagnetic resonance (EPR), and single‐crystal X‐ray diffraction studies. Complex 1 crystalizes in a monoclinic crystal system with space group P21/c, and the lattice parameters were recorded as a = 18.95 Å, b = 17.81 Å, c = 20.56 Å, and α = γ = 90° and β = 117.12° per unit cell. The density functional theory (DFT) studies were performed to comprehend the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) electron densities over the complex 1 and the energy difference in between them. Hirshfeld surface studies were performed to understand the various non‐covalent interactions including OH····O, NH····H, and CH····O, which determined the stability of crystal lattice framework. The preliminary in vitro binding studies of complex 1 with human serum albumin (HSA) and bovine serum albumin (BSA) targets was carried out to determine the binding mode and to evaluate its cytotoxic potential using various biophysical techniques. The antioxidant activity of complex 1 was examined against the free radical 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) using ascorbic acid as standard, which demonstrated higher radical scavenging activity (IC50 = 14 μM). Furthermore, the cytotoxic action of complex 1 was evaluated using 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay against MDA‐MB‐231 (triple‐negative breast) and A549 (lung) cancer cell lines, which revealed remarkable cytotoxicity of the complex against the tested cancer cell lines that was reflected in their low IC50 values.
Palladium‐Catalyzed Hydroxycarbonylation of Diisobutene: Systematic Optimization by Central Composite Design
Authors: Dühren Ricarda , Kucmierczyk Peter , Jackstell Ralf , Franke Robert , Beller Matthias
Published: September 2022

The selection of suitable catalysts and reaction conditions are key elements for efficient process development. In this work, stability studies of homogeneous palladium catalysts used for the hydroxycarbonylation of olefins to aliphatic carboxylic acids are presented. Based on this, the hydroxycarbonylation of diisobutene, which represents an industrially relevant mixture of olefins, was investigated and optimized by means of central composite design with respect to the yield of the target product 3,5,5‐trimethylhexanoic acid. The modeling succeeds with high accuracy and allows to gain information about interactions between different factors in the reaction system. This allows a more accurate prediction of the reaction behavior and permits easier future scale‐up of such processes.
A methodological validation of psychophysical approaches for quantifying the color discrimination capability of white light sources
Authors: Li Zhenzhen , Liu Ying , Liang Jinxing , Liu Qiang , Pointer Michael R. , Khanh Tran Quoc
Published: September 2022

In this study, three psychophysical approaches that quantify the color discrimination capability of white light sources were systematically compared. A total of 11 light sources, five of 5500 K and six of 3000 K, were tested in two groups using three typical psychophysical methods including the Farnsworth‐Munsell100 Hue Test, real objects observation and color blocks comparison. The experimental results show that the examined approaches led to consistent conclusions on the color discrimination performance of lighting but differences in the robustness, complexity, and comprehensiveness of the methods were observed. Interestingly, sex difference in color discrimination was found to be influenced by visual judgment protocols. Based on this validation, methodological suggestions for future research on the color discrimination of lighting are proposed.
Board gender diversity and corporate green innovation: An industry‐level institutional perspective
Authors: Naveed Khwaja , Khalid Fahad , Voinea Cosmina Lelia
Published: September 2022

This study contributes to the inconclusive literature on the relationship between board gender diversity (BGD) and green innovation (GI). It empirically examines the moderating role of normative, mimetic and coercive pressures in the relationship between BGD and GI, derived from an industry‐specific isomorphic exhibition of institutional theory. Appertaining to A‐share listed firms of China, the findings highlight the moderating effect of masculinity, environmental sensitivity, environmental regulation level and export orientation of an industry on the said relationship. Moreover, the coercive isomorphism exhibits pronounced impact with the intensity of export orientation. However, firms associated with high‐tech industries have not been confirmed for significant effect on the relationship. Thus, the findings imply that the dynamics of the corporate governance and institutional isomorphism in case of BGD and GI relationships, in the organisational field of industry, are likely both pertinent and prevalent. Moreover, the increase in the number of females on the corporate boards could enhance the green performance of a firm, subject to the fulfilment of industry specific boundary conditions, predefined by the unique set of industry specific institutional pressures. These pressures amid affiliation with a specific industry should be evaluated and controlled for, on the bases of coercive, normative, and mimetic isomorphism it hatches, to device an optimum composition of the corporate board.
Lipid Recovery from Concentrated Emulsions by Freezing–Thawing as an Alternative to Solvent‐Based Extraction: A Case Study on Mayonnaise
Authors: Okuro Paula K. , Viau Michèle , Kermarrec Alice , Cunha Rosiane L. , Meynier Anne , Berton‐Carabin Claire
Published: September 2022

Most analyses concerning the characterization of lipids present in complex food systems require separation and recovery of lipids prior to analysis. This may be achieved, for example, by solvent‐based extractions. In the case of concentrated emulsions, targeted physical destabilization and phase separation induced by a freeze–thaw treatment are also considered. This strategy would imply a simple, solvent‐free method with a high yield. In the present work, conventional mayonnaise and a vegan alternative are evaluated. The effect of the freezing–thawing conditions on lipid recovery, as compared to a classical solvent (hexane:n‐2‐propanol, 3:2 v/v)‐based extraction is investigated. In particular, two freezing temperatures (−20 and −80 °C) and the presence or not of additional water to aid phase separation are evaluated. The freezing temperature (which directly influences the rate and extent of water and lipid crystallization) largely impacts lipid recovery, in a matrix‐dependent manner: −20 °C is clearly the most suitable temperature for the conventional mayonnaise, whereas −80 °C seems somewhat better for the vegan alternative. Importantly, this alternative freezing–thawing approach does not alter the fatty acid composition nor the lipid class profile compared to a classical solvent extraction, which confirms its relevancy from a subsequent analytical perspective.

Practical Applications: The induction of emulsion destabilization by freezing–thawing is a simple, high‐yield and solvent‐free methodology (i.e., compatible with green chemistry) for lipid recovery regarding analytical purposes. Lipid recovery can be greatly improved by settling the involved conditions. Herein authors propose some guidelines for selecting and reasoning over procedure parameters in concentrated emulsions. The performance of lipid recovery is tuned by the conditions of freezing and guided by the type of emulsion.
Pyrosequencing: Current forensic methodology and future applications—a review
Authors: Ghemrawi Mirna , Tejero Nicole Fernandez , Duncan George , McCord Bruce
Published: September 2022

The recent development of small, single‐amplicon‐based benchtop systems for pyrosequencing has opened up a host of novel procedures for applications in forensic science. Pyrosequencing is a sequencing by synthesis technique, based on chemiluminescent inorganic pyrophosphate detection. This review explains the pyrosequencing workflow and illustrates the step‐by‐step chemistry, followed by a description of the assay design and factors to keep in mind for an exemplary assay. Existing and potential forensic applications are highlighted using this technology. Current applications include identifying species, identifying bodily fluids, and determining smoking status. We also review progress in potential applications for the future, including research on distinguishing monozygotic twins, detecting alcohol and drug abuse, and other phenotypic characteristics such as diet and body mass index. Overall, the versatility of the pyrosequencing technologies renders it a useful tool in forensic genomics.
Real‐time forecasting of the Australian macroeconomy using flexible Bayesian VARs
Authors: Hou Chenghan , Nguyen Bao , Zhang Bo
Published: September 2022

This paper evaluates the real‐time forecast performance of alternative Bayesian autoregressive (AR) and vector autoregressive (VAR) models for the Australian macroeconomy. To this end, we construct an updated vintage database and compare the predictive ability of a wide set of specifications that takes into account almost all possible combinations of nonstandard errors existing in the current literature. In general, we find that the models with flexible covariance structures can improve the forecast accuracy as compared with the standard variant. For forecasting GDP, both point and density forecasts consistently suggest small VARs tend to outperform their counterparts while AR models often predict inflation better. With the unemployment rate, large VAR models provide superior forecasts to the alternatives at almost all forecast horizons. The forecasting performance of these models slightly changes when we consider the first, second, and latest‐available vintage as actual values, highlighting the importance of using real‐time data vintages in forecasting.
Ggtree: A serialized data object for visualization of a phylogenetic tree and annotation data
Authors: Xu Shuangbin , Li Lin , Luo Xiao , Chen Meijun , Tang Wenli , Zhan Li , Dai Zehan , Lam Tommy T. , Guan Yi , Yu Guangchuang
Published: September 2022

While phylogenetic trees and associated data have been getting easier to generate, it has been difficult to reuse, combine, and synthesize the information they provided, because published trees are often only available as image files and associated data are often stored in incompatible formats. To increase the reproducibility and reusability of phylogenetic data, the ggtree object was designed for storing phylogenetic tree and associated data, as well as visualization directives. The ggtree object itself is a graphic object and can be rendered as a static image. More importantly, the input tree and associated data that are used in visualization can be extracted from the graphic object, making it an ideal data structure for publishing tree (image, tree, and data in one single object) and thus enhancing data reuse and analytical reproducibility, as well as facilitating integrative and comparative studies. The ggtree package is freely available at https://www.bioconductor.org/packages/ggtree.
Are “job hoppers” trapped in hedonic treadmills? Effects of career orientations on newcomers' attitude trajectories
Authors: Doden Wiebke , Pfrombeck Julian , Grote Gudela
Published: September 2022

Joining a new organization to change jobs is an influential event in an employee's career. Thus, inter‐organizational job changes have sparked growing scholarly interest, especially in the temporal dynamics involved in detaching from organizations and adapting to new ones. While it is widely accepted that employees adapt differently to job changes, the influence of employees' career orientations on changes in job attitudes has not yet been considered. This is surprising given that a key difference between self‐centered and organization‐centered career orientations is a positive attitude toward job changes. Building on hedonic adaptation, we examined how career orientations influence changes in job satisfaction and turnover intention throughout a job change. We compared self‐centered and organization‐centered employees using random coefficient modeling on two longitudinal data sets with voluntary job changers. Our results illustrate that self‐centered career orientations foster a stronger decline in job satisfaction with the new employer, as well as a larger increase in turnover intention, than organization‐centered career orientations. In contrast, employees with organization‐centered career orientations experienced an upward trend in job satisfaction toward the end of the first year. Our findings offer important implications for research on the determinants of job attitude trajectories when individuals join a new organization.
The role of direct equity ownership in supply chains
Authors: Haw In‐Mu , Swink Morgan , Zhang Wenlan
Published: September 2022

This study examines the effect of direct equity ownership (DO) a buyer holds in its supplier on financial performance and operations of the supplier and buyer. Based on a sample of US buyer–supplier pairs from 1982 to 2017, we find that DO benefits buyer performance, but not supplier performance. The results support the view that DO mainly provides greater control for the buyer. Furthermore, we find that the performance effects of DO are moderated by firm characteristics that engender dependence. The beneficial influence of DO on a buyer's performance is more pronounced when the buyer is more innovative or operates in a more competitive environment. Our examination of the effects of DO on the operations of suppliers and buyers finds that suppliers in buyer–supplier relationships (BSRs) with higher DO invest more in relationship‐specific assets (R&D), provide more trade credits, and have lower gross profit margins. Buyers in BSRs with higher DO receive more trade credits and have lower cost of goods sold when the purchases of the buyer from the supplier make up a high proportion of the buyer's cost of goods sold. Overall, these results suggest that DO primarily benefits the buyer at the expense of the supplier, a finding that is consistent with the effects of bargaining and control power of the buyer. We discuss the implications of these findings for practitioners and for extensions to both relational and resource dependence theories.
Berberine alleviates intestinal barrier dysfunction in glucolipid metabolism disorder hamsters by modulating gut microbiota and gut‐microbiota‐related tryptophan metabolites
Authors: Chen Yuting , Hao Zhangsen , Zhao Han , Duan Xiaofeng , Jia Dongsheng , Li Kaipeng , Yang Yuxin , Cui Hongjuan , Gao Mingming , Zhao Ding
Published: September 2022

BACKGROUND

Barberry plants can be considered as useful additives and functional compounds in various industries, especially in the food industry. Berberine (BBR), the most important functional compound in the barberry roots, has recently been used to treat obesity, diabetes, and atherosclerosis. Gut microbiota and the intestinal barrier play an important role in the development of glucolipid metabolism disorders (GLMDs). However, the association of gut microbiota metabolism disorder and the intestinal barrier dysfunction effect of BBR in GLMDs remains elusive.

RESULTS

The results showed that administration of BBR could increase the number of colonic glands and goblet cell mucus secretion, improve the intestinal barrier function, and reduce the serum glycolipid level in GLMD hamsters. Interestingly, BBR was metabolized into 12 metabolites by gut microbiota, and the main metabolic pathways were oxidation, demethylation, and hydrogenation. In addition, BBR significantly improved the species diversity and uniformity of gut microbiota and promoted the proliferation of beneficial microbiota. Furthermore, the levels of tryptophan metabolites, such as indole, indole‐3‐acetamide, indole‐3‐acetaldehyde, indole‐3‐pyruvic acid, and indole‐3‐acetic acid were significantly altered by BBR. Both the intestinal tight junction proteins and intestinal immune factors were altered by BBR.

CONCLUSION

BBR could alleviate intestinal barrier dysfunction of GLMDs by modulating gut microbiota and gut‐microbiota‐related tryptophan metabolites, which may be one of the pharmacological mechanisms for the treatment of GLMDs. © 2022 Society of Chemical Industry.
Implementing advanced practice nursing in France: A country‐wide survey 2 years after its introduction
Authors: Devictor Julie , Burnet Espérie , Henriot Tatiana , Leclercq Anne , Ganne‐Carrie Nathalie , Kilpatrick Kelley , Jovic Ljiljana
Published: September 2022

Objectives

To examine the characteristics of the first Advanced Practice Nurses in France and to compare the French model to international standards.

Background

Common barriers and facilitators to their integration in healthcare provision have been identified internationally. In France, the legislative framework was introduced in 2016, and the first graduates entered the workforce in 2019.

Methods

The French model was examined in comparison with Hamric's conceptual framework and to the International Council of Nurses' guidelines and definitions. A cross‐sectional survey was also conducted, using three self‐administered online questionnaires. Two were distributed to 2019 and 2020 graduates and a third to the accredited programme directors. The characteristics of advanced practice nursing graduates were described and compared based on employment status and field of practice (primary vs secondary/tertiary care).

Results

Although the French model of advanced practice nursing meets Hamric's primary criteria and core competencies, it does not differentiate between Nurse Practitioner and Clinical Nurse Specialist roles. Of the 320 students enrolled in one of the 11 accredited training programmes 165 participated in the survey. Mean age was 40, and mean prior nursing experience was 15 years. By February 2021, 30% of respondents were still employed as Registered Nurses. Barriers to practice included insufficient income generation (primary care), the lack of position creation (secondary/tertiary care), the physician‐dependent patient referral process and delays in prescription credentials approval.

Conclusions

The implementation of advanced practice nursing in France faces several barriers. Legislative adjustments and greater financial incentives to practice seem warranted.Relevance to clinical practice: as in other countries, France introduced advanced practice nursing to respond to the Public Health challenge of improving access to quality health care in the context of increasing chronic disease prevalence and limited resource allocation. Facilitating its integration in the healthcare provision landscape seems paramount.
Effect of woven structure and aramid binder yarn on the flexural performance of carbon/aramid fiber hybrid three‐dimensional woven composites
Authors: Liu Yajun , Natsuki Toshiaki , Huang Canyi , Nakajima Takashi , Xia Hong , Ni Qing‐Qing
Published: September 2022

Three‐dimensional (3D) woven textile‐reinforced composites have drawn much attention because of their specific geometries, improved composite interlayer strength, and impact‐resistance performance. In this study, three types of 3D woven structures with different binder‐yarn ratios and paths were designed based on a traditional dobby‐weaving loom with a special weft‐interlock structural design. Carbon/aramid fiber‐reinforced plastic (CAFRP) composites with carbon warp, weft, and aramid binder yarns, as well as carbon fiber‐reinforced plastic (CFRP) composites were reinforced using the three types of woven structures and consolidated with epoxy resin. The quasi‐static and dynamic flexural performance of these 3D woven composites were experimentally investigated using a three‐point bending test and a low‐velocity drop‐weight impact test. Nondestructive ultrasonic C‐scan and X‐ray microcomputed tomography were applied to characterize the failure mode of the impacted composites. Woven structure and aramid binder yarn with a coarse count have a coupling effect on the quasi‐static flexural performance of the 3D woven CAFRP composites. A larger volume combined with a smaller through‐thickness waviness degree of aramid binder yarn has a similar effect with a smaller volume combined with a larger waviness degree. Introducing aramid binder yarn in the hybrid composites lowered the quasi‐static flexural performance to a certain extent (0.28%–47.74% and 5.29%–49.63% for flexural modulus and strength, respectively) but increased the impact performance significantly (e.g., increasing 23.6%–92.7% peak‐load values under 6‐J impacts). A larger volume combined with a smaller waviness degree of the aramid binder yarn introduced in these woven structures contributed more to impact‐resistance and damage‐tolerance performance.
Diamond‐Based Nanoscale Quantum Relaxometry for Sensing Free Radical Production in Cells
Authors: Sigaeva Alina , Shirzad Hoda , Martinez Felipe Perona , Nusantara Anggrek Citra , Mougios Nikos , Chipaux Mayeul , Schirhagl Romana
Published: September 2022

Diamond magnetometry makes use of fluorescent defects in diamonds to convert magnetic resonance signals into fluorescence. Because optical photons can be detected much more sensitively, this technique currently holds several sensitivity world records for room temperature magnetic measurements. It is orders of magnitude more sensitive than conventional magnetic resonance imaging (MRI) for detecting magnetic resonances. Here, the use of diamond magnetometry to detect free radical production in single living cells with nanometer resolution is experimentally demonstrated. This measuring system is first optimized and calibrated with chemicals at known concentrations. These measurements serve as benchmarks for future experiments. While conventional MRI typically has millimeter resolution, measurements are performed on individual cells to detect nitric oxide signaling at the nanoscale, within 10–20 nm from the internalized particles localized with a diffraction limited optical resolution. This level of detail is inaccessible to the state‐of‐the‐art techniques. Nitric oxide is detected and the dynamics of its production and inhibition in the intra‐ and extracellular environment are followed.
Influence of Carbide Types and Amounts on the Wear of Graphite‐Containing Alloys for Work Rolls
Authors: Paar Armin , Aigner Michael , Reiter Maximilian , Fischbacher Martina , Laubbichler Ingrun
Published: September 2022

In the surface‐critical stands in hot rolling mills, the so‐called indefinite‐chill alloys are used as shell materials for the work rolls. The microstructure of these materials consists of cementite and graphite, as well as different other carbides, which are embedded in a martensitic/bainitic matrix. In the past 10 years, indefinite‐chill materials are intensively developed to meet the higher requirements in today's rolling mills. To measure the increase of the wear resistance, a wear test rig is designed and developed, which allows testing work roll materials under conditions that are very close to those in a rolling mill but still on a laboratory scale. This study shows the investigation results of four different indefinite‐chill and graphitic HSS alloys with different carbide amounts and types. The strong influence of MC and M2C/M6C‐carbides can be clearly seen but besides the carbides, also other microstructural phases have an influence on the wear of the alloys. It can be confirmed that with higher fractions of hard carbides the wear on the tested materials decreases. The results also clearly show that there has to be a correct balance between the different carbide types as well as the balance between the carbide, graphite, and matrix fractions.
Tensile behavior of cruciform stubs with four bolts per row
Authors: Wang Peng , Xu Jing , Li Jianxin , Yu Lie
Published: September 2022

The stiffened top‐and‐seat angle connection is widely used in earthquake‐prone areas, and additional tensile bolts on angles' column leg effectively improve its bending behavior. However, such design and construction are not governed by any regulations. It is urgent to figure out the mechanical behavior and develop accurate theoretical methods. Based on the component method, this paper first conducted an experimental study on the extracted cruciform stubs with four bolts per row. It compared the tensile properties and damage modes for different thicknesses. After that, the further parametric analysis compared the impact of stub thickness, bolt arrangement, and whether or not the bolt was pretensioned after validation. Stub thickness and bolt gauge were observed with a greater impact than the bolt distance on the plastic resistance. Furthermore, a prediction model for the plastic resistance of the cruciform stub with four bolts per row is proposed by integrating approaches for classic stiffened and unstiffened angles.
Pedotransfer functions developed for calculating soil saturated hydraulic conductivity in check dams on the Loess Plateau in China
Authors: Cao Taohong , She Dongli , Zhang Xiang , Yang Zhen , Wang Guangbo
Published: September 2022

Soil saturated hydraulic conductivity (Ks) is a key soil hydraulic property that determines the hydrological cycle of check dam–dominated catchment areas. However, Ks data are lacking due to the difficulty of directly measuring this variable in deep soil layers. In this study, 45 soil profiles (0–200 cm) in 15 check dams in three typical watersheds (Xinshui River, Zhujiachuan, and Kuye River) in a hilly gully region on the Chinese Loess Plateau were selected, and a total of 586 soil samples were collected along the soil profiles. Backpropagation neural network (BPNN) and support vector regression (SVR) models based on the genetic algorithm (GA) were tested, and pedotransfer functions for Ks estimation were established for check dams on the Loess Plateau. Basic soil characteristics, such as soil depth, sand, silt, clay, soil organic matter, and bulk density, were adopted as the model inputs to estimate Ks. Combinations of these parameters could be used to suitably estimate Ks, and the models were found to require relatively few soil characteristics to achieve similar accuracy. In comparison to GA‐BPNN, the GA‐SVR model attained good practicability and was more stable in Ks prediction (the geometric mean error ratio was between 0.942 and 1.101; RMSE was between 0.069 and 0.073). Our research can make some contributions to the solution of land restoration and watershed governance on the Chinese Loess Plateau.
Introduction to Dark Matter
Authors: Jackson Kimball Derek F. , Budker Dmitry
Published: September 2022

To set the stage for our study of ultralight bosonic dark matter (UBDM), we review the evidence for the existence of dark matter: galactic and stellar dynamics, gravitational lensing studies, measurements of the cosmic microwave background radiation (CMB), surveys of the large-scale structure of the universe, and the observed abundance of light elements. This diverse array of observational evidence informs what we know about dark matter: its universal abundance, its spatial and velocity distribution, and that its explanation involves physics beyond the Standard Model. But what we know about dark matter is far outweighed by what we do not know. We examine UBDM in the context of several of the most prominent alternative hypotheses for the nature of dark matter: weakly interacting massive particles (WIMPs), sterile neutrinos, massive astrophysical compact halo objects (MACHOs), and primordial black holes (PBHs). Finally we examine some of the key general characteristics of UBDM, including its wavelike nature, coherence properties, and couplings to Standard Model particles and fields.
Magnetic Resonance Searches
Authors: Blanchard John W. , Sushkov Alexander O. , Wickenbrock Arne
Published: September 2022

Ultralight bosonic dark matter (UBDM), such as axions and axionlike particles (ALPs), can interact with Standard Model particles via a variety of portals. One type of portal induces electric dipole moments (EDMs) of nuclei and electrons and another type generates torques on nuclear and electronic spins. Several experiments search for interactions of spins with the galactic dark matter background via these portals, comprising a new class of dark matter haloscopes based on magnetic resonance.
Dark Matter Radios
Authors: Jackson Kimball Derek F. , Phipps Arran
Published: September 2022

Many theories predict that ultralight bosonic dark matter (UBDM) can couple to photons and thus generate electromagnetic signals. In such scenarios, UBDM can be searched for using a radio: an antenna connected to a tunableLCcircuit that is in turn connected to an amplifier. Such “dark matter radios” are particularly useful tools to search the broad range of UBDM wavelengths where resonant cavity dimensions are too large to be practical. In this chapter, we discuss how dark matter radios can be used to search for UBDM, focusing on the case of hidden photons.
Heterotic strings on $$ \mathbbm{T} $$3/ℤ2, Nikulin involutions and M-theory
Authors: Acharya Bobby Samir , Aldazabal Gerardo , Font Anamaría , Narain Kumar , Zadeh Ida G.
Published: September 2022

Abstract

We first describe the low energy dynamics of ten dimensional heterotic supergravity compactified on the smooth, flat 3-manifold$$ \mathbbm{T} $$T3/ℤ2, without supersymmetry, and explain how it arises from flat heterotic gauge fields. The semi-classical theory has both Coulomb and Higgs branches of non-supersymmetric vacua. We then give an exact worldsheet description as asymmetric orbifolds of$$ \mathbbm{T} $$T3, where the orbifold generator involves a Nikulin non-symplectic involutionθof the even self-dual lattice Γ(19,3). Along the way we briefly compare our findings with M-theory on K3/θ. Our construction gives a novel CFT description of the semi-classical field theory moduli space. In particular, the Wilson line parameters in the latticeI⊂ Γ(19,3)of signature (19− s,1) which is invariant underθ, and in its orthogonal complementN, correspond respectively to Coulomb and Higgs branch moduli. There is a rich pattern of transitions amongst Higgs and Coulomb branches which we describe using the worldsheet theory.
Master equations for de Sitter DFPs
Authors: Buchel Alex
Published: September 2022

Abstract

We develop master equations to study perturbative stability of de Sitter Dynamical Fixed Points (DFPs) of strongly coupled massive quantum field theories in d + 1 space-time dimensions with a holographic dual. The derived spectrum of linearized fluctuations characterizes the late-time dynamics of holographic strongly coupled non-conformal gauge theories in de Sitter background. Numerous checks and examples are presented.
Fixed points of (0,2) Landau-Ginzburg renormalization group flows and the chiral algebra
Authors: Bertolini Marco , Melnikov Ilarion V. , Plesser M. Ronen
Published: September 2022

Abstract

We discuss renormalization group flows in two-dimensional quantum field theories with (0,2) supersymmetry. We focus on theories with UV described by a Landau-Ginzburg Lagrangian and use the chiral algebra to constrain the IR dynamics. We present examples where the structure of the chiral algebra is incompatible with unitarity of the IR superconformal theory and discuss the implications of this result for programs of classifying (0,2) SCFTs as endpoints of flows from simple Lagrangian theories.
Analytic expansions of multi-hadron finite-volume energies. I. Two-particle states
Authors: Grabowska D. M. , Hansen M. T.
Published: September 2022

Abstract

We derive analytic expansions for the finite-volume energies of weakly-interacting two-particle systems, using the general relations between scattering amplitudes and energies derived by Lüscher and others. The relations hold for ground and excited states with both zero and non-zero total momentum in the finite-volume frame. A number of instructive aspects arise in the derivation, including the role of accidental degeneracies and the importance of defining a power-counting scheme in the expansions. The results give intuition concerning the imprint of perturbative interactions on the energy spectrum, while also providing a useful basis for the analogous results concerning three-particle excited states, to appear. We have also developed a Mathematica notebook that automates the expansions described in this work.
Active Control of Highly Autocorrelated Machinery Noise in Multivariate Nonminimum Phase Systems
Authors: Meller Michał , Lasota Adam
Published: September 2022

In this paper, a novel multivariate active noise control scheme, designed to attenuate disturbances with high autocorrelation characteristics and preserve background signals, is proposed. The algorithm belongs to the class of feedback controllers and, unlike the popular feedforward FX-LMS approach, does not require availability of a reference signal. The proposed approach draws its inspiration from the iterative learning control and repetitive mode control methods, and employs a modified inverse model learning law. The classical inverse model learning law is well known to offer fast convergence and high steady-state performance, provided that the secondary path is minimum phase and well known. The proposed modified inverse model learning law employs a spectral factorization trick, which allows one to use the method with nonminimum phase plants of arbitrary order. Moreover, our scheme includes a controller bandwidth limiting mechanism that can be used to tune the disturbance rejection bandwidth and to improve the closed-loop robustness to errors in the model of the secondary path. The algorithm’s behavior and performance are verified with computer simulations that demonstrate suppression of electrical transformer noise and include realistic models of the secondary path. The results show high-level selective attenuation and fast convergence.
Schinzel Hypothesis on average and rational points
Authors: Skorobogatov Alexei N. , Sofos Efthymios
Published: September 2022

We resolve Schinzel’s Hypothesis (H) for $$100\%$$

100
%

of polynomials of arbitrary degrees. We deduce that a positive proportion of diagonal conic bundles over $${\mathbb {Q}}$$
Q
with any given number of degenerate fibres have a rational point, and obtain similar results for generalised Châtelet equations.
Implementing Bundle Care in Major Abdominal Emergency Surgery: Long‐Term Mortality and Comprehensive Complication Index
Authors: Trangbæk Rune Munch , Burcharth Jakob , Gögenur Ismail
Published: September 2022

Background

Major abdominal emergency surgery (MAES) has a high risk of postoperative mortality and a high complication rate. The aim of this study was to evaluate whether the implementation of a perioperative care bundle reduced long‐term mortality and the Comprehensive Complication Index (CCI) after MAES.

Methods

This study was a single‐centre retrospective cohort study. Data in the intervention group were collected prospectively and compared with a historical cohort from the same centre. It includes adult patients undergoing MAES. We implemented a care bundle under the name Abdominal Surgery Acute Protocol (ASAP). We initiated fast‐track initiatives and standardised optimised care in before, during and after surgery. Data were analysed using survival analysis and multiple regression.

Results

We included 120 patients in the intervention cohort and 258 in the historical cohort. The one‐year mortality rate was 21.7% in the intervention cohort compared to 28.3% in the standard care cohort. Adjusted odds ratio of one‐year mortality 0.81 (CI95% 0.41–1.56). The 30‐day mortality was lowered from 19.0 to 6.7% (p = 0.003). The CCI in the intervention cohort was 8.7 (IQR 0–34) compared to 21 (IQR 0–36) in the control cohort (p = 0.932) The length of stay increased by two days (p = 0.021). Most cases had 71–80% protocol compliance.

Conclusion

Implementing bundle care in major abdominal emergency surgery lowered the 30‐day postoperative mortality. The difference in mortality was preserved over time although not significant after one year. The changes in the Comprehensive Complication Index were not statistically significant.
Willingness to pay for health gains from an international integrated early warning system for infectious disease outbreaks
Authors: Perry-Duxbury Meg , Himmler Sebastian , van Exel Job , Brouwer Werner
Published: September 2022

Recently, due to the corona virus outbreak, pandemics and their effects have been at the forefront of the research agenda. However, estimates of the perceived value of early warning systems (EWSs) for identifying, containing, and mitigating outbreaks remain scarce. This paper aims to show how potential health gains due to an international EWS might be valued. This paper reports on a study into willingness to pay (WTP) in six European countries for health gains due to an EWS. The context in which health is gained, those affected, and the reduction in risk of contracting the disease generated by the EWS are varied across seven scenarios. Using linear regression, we analyse this ‘augmented’ willingness to pay for a QALY (WTP-Q) for each of the scenarios, where ‘augmented’ refers to the possible inclusion of context specific elements of value, such as feelings of safety. An initial WTP-Q estimate for the basic scenario is €17,400. This can be interpreted as a threshold for investment per QALY into an EWS. Overall, WTP estimates move in the expected directions (e.g. higher risk reduction leads to higher WTP). However, changes in respondents’ WTP for reductions in risk were not proportional to the magnitude of the change in risk reduction. This study provided estimates of the monetary value of health gains in the context of a pandemic under seven scenarios which differ in terms of outcome, risk reduction and those affected. It also highlights the importance of future research into optimal ways of eliciting thresholds for investments in public health interventions.
Watch who you trust! A structured literature review to build a typology of e-government risks
Authors: Distel Bettina , Koelmann Holger , Plattfaut Ralf , Becker Jörg
Published: September 2022

The information systems, e-business, and e-government literature has unanimously shown that trust and risk are antecedents of the use of information technology and technology-based services. However, a deeper understanding of the relationship between trust and risk, especially when taking into account the extensive knowledge created in fields such as organisational science and psychology, is often missing. With this article, we aim at conceptualizing risk in e-government use. Based on a structured review of the trust-related e-government literature, we derive a typology of relevant e-government risks. We analyse this typology in light of extant trust and risk literature. The typology can be used both to understand the behaviour of system or service users and to design systems and services that can be and are trusted. As such, this research can serve as a basis for future research on the role of trust and risk in designing and using e-government services. The generalizability to e-business services and information systems in general is discussed.
Sexualized Behavior Among Adolescents Who Sexually Offended
Authors: Krause Chiara , Barra Steffen , Landolt Markus A. , Bessler Cornelia , Aebi Marcel
Published: September 2022

Early or excessive sexualized behaviors and preoccupations with sexuality (SB) exhibited by juveniles who have sexually offended (JSO) are considered risk factors for sexual recidivism. However, research into SB among JSO is scarce. The present study retrospectively examined prevalence rates and patterns of SB among JSO prior to sexual offending and their relation to psychopathology and sexual recidivism. We systematically assessed information from psychiatric and psychological expert reports in case files of 230 JSO aged 12–18 years (M = 14.46, SD = 1.49) from a population sample of JSO with contact sexual offenses. A total of 93 (40.4%) JSO exhibited SB prior to the index sexual offense. Latent class analysis revealed three SB profiles: (1) “low/no SB” (n = 188), (2) “preoccupied SB” (preoccupation with sexuality, e.g., early pornography consumption, excessive masturbation; n = 29), and (3) “dysregulated SB” (exhibiting inappropriate sexualized behaviors toward others, e.g., sexualized speech, touching others inappropriately; n = 13). The preoccupied SB and the dysregulated SB groups showed higher prevalence of psychiatric disorders than the low/no SB. However, none of the JSO of the preoccupied SB or dysregulated SB groups reoffended sexually within 365 days after conviction for the sexual index offense (low/no SB: 12.8%). Overall, our findings do not support a general notion of the presence of SB as an indicator of high risk for persistent sexual offending among JSO. Instead, JSO with SB appear particularly burdened regarding a range of psychiatric disorders that should be treated accordingly.