bluuebunny/crossref_metadata_2025_split huggingface dataset:
Unraveling the dependence of proton transfer on solvent polarity in ion pairs of carbamates and dithiocarbamates with nitrogen‐based counterions
Authors: Poon Louis , Hum Jacob R. , Kertesz Miklos , Weiss Richard G. 
Published: April 2023

AbstractSmall, but important, differences in the structure–property relationships between ionomers composed of amidinium or imidazolinium groups with alkylcarbamate or alkyldithiocarbamate counterions have been examined experimentally by us previously. To unravel the sources of these differences, DFT calculations are conducted here for ion‐pair complexes (IPs) of these systems and their corresponding uncharged base and acid components (NPs). Calculations include IPs and NPs in which the amidine/amidinium and imidazoline/imidazolinium groups are anchored to a dimethylsiloxane pentamer. A surprising dependence of proton transfer on the dielectric constant (ε) of the medium is found for the systems: Whereas interconversion between the NPs and IPs is strongly dependent on medium dielectric in systems with an alkylcarbamate, none of the initial IP forms with an alkyldithiocarbamate transforms to an NP. Although the calculations do not include individual solvent–solute molecular interactions, they do probe how the components sense their bulk environments. The lack of detectable reversible proton transfer from the amidinium or imidazolinium cations to the dithiocarbamates is consistent with the “principle of proton affinity/pKa equivalence”: Because the acidity of dithiocarbamates is higher than that of carbamates, the gap between their proton affinities (ΔPA) is decreased, favoring stronger electrostatic‐based H‐bonds in the ion‐pair complexes of the dithiocarbamates. The differences can also be estimated from the Deuri–Phukan nucleophilicity index scale, which is based on DFT calculations and suggests a strong dependence of proton transfer on the nucleophilicity of the base and the dielectric constant of the solvent. Predictions from these calculations on some important experimental systems are mentioned.
The institutional antecedents of sustainable development in cultural heritage tourism
Authors: Mzembe Andrew Ngawenja , Koens Ko , Calvi Licia 
Published: April 2023

AbstractThis paper consolidates the fragmented literature and evidence by highlighting the three important lenses on the institutional antecedents of sustainable development agenda in cultural heritage tourism. Our study, therefore, identifies three distinct institutional antecedents olensesf sustainable development in cultural heritage tourism such as governance mechanisms, community agency, and the influence of supranational institutions. It demonstrates that sustainable cultural heritage tourism is multidimensional as it spans institutional and sectoral domains. This study brings to light the interplay of these elements and further evaluates their efficacy in embedding the sustainable development agenda in cultural heritage tourism. It also contributes to the literature by bringing to light the current state of the literature on institutional antecedents of sustainable development in cultural heritage tourism. This allows our study to attempt to show the scope of the current knowledge about institutional antecedents and their relationship with sustainable cultural heritage tourism. Most importantly, the study identifies gaps in the research on institutional antecedents and sustainable cultural heritage tourism—the basis on which future research directions have been identified and suggested.
Ecological development practices of marine ranching enterprises in China: Case studies of early movers
Authors: Wang Ye‐Cheng , Fan Yi‐Pin , Du Yuan‐Wei 
Published: April 2023

AbstractMarine ranching can help solve the dilemma facing food systems by providing more food for humans under the constraints of resources and the environment. Many marine ranching enterprises have committed to ecological development to help advance the 2030 Sustainable Development Goals. Little is known, however, about the drivers, initiatives, and performance implications of this behavior. To fill this gap, we conducted case studies of five early movers among marine ranching enterprises in China. These firms took both fishery output and environmental protection into consideration and achieved significant results. We identified six main drivers: “synergistic benefits,” “sustainable business value,” “government incentive and supervision,” “sense of social responsibility,” “environmental pressure,” and “market enforcement.” The main initiatives, meanwhile, were “habitat restoration,” “ecological production,” “science and technology innovation,” “ecological operation,” and “ecological management.” We showed that businesses' ecological development practices can generate synergistic benefits, including economic, environmental, and social benefits. Moreover, based on our key path analysis of early movers' ecological development practices, we developed an ecological development model to illustrate their successful experiences. This model can help guide other businesses toward fulfilling their ecological development commitments.
The disparate economic outcomes of stigma: Evidence from the arms industry
Authors: Sadri Mohamad , Piazza Alessandro , Phung Kam , Helms Wesley 
Published: April 2023

AbstractResearch SummaryOrganizational stigma has been commonly associated with a number of negative economic externalities in prior literature, but the mechanism by which this occurs and the extent of the associated consequences have received little attention. We address these gaps by theorizing that stigmatizing labels damage the legitimacy of the target by highlighting a deviation from the expectations of relevant audiences. We also argue that the content and focus of stigmatizing labels, as well as the features of the stigmatizer audience deploying them, will affect the magnitude of the negative economic consequences of stigma. Through an analysis linking the condemnation of arms producers in the media between 1998 and 2016 to cumulative abnormal returns (CAR) in the stock market, we find broad support for our arguments.Managerial SummaryThis paper examines the economic impact of stakeholder criticism on firms, using data from the global arms industry to develop a typology of criticism based on its content, focus, and origin. We find that criticism can negatively affect a firm's stock market returns, particularly when those criticizing have the authority to condemn specific behaviors. Civil society entities like nonprofits or the media, politicians, and economic players such as investors each have unique authority to criticize harmful behavior, illegal behavior, and unethical affiliations, respectively. Understanding the different types of criticism and their potential economic consequences can help firms better manage stakeholder relationships and mitigate negative impacts on their financial performance.
Design teams and industry life cycles: The interplay of innovation and complexity
Authors: Padhee Soumyakant , Lore Nunzio , Heydari Babak 
Published: April 2023

AbstractThis paper studies how innovation teams can be optimally configured to yield the best possible performance at different stages of a certain technology's life cycle, which correspond to different levels of environmental complexity. To conduct our analysis, we have employed computational simulations of communities searching NK landscapes at varying levels of complexity. We studied how the relative proportion of exploring agents to exploiting agents in a community impacts the evolution of scores over time, and conducted additional investigations into the role of specialization (i.e., the agents' propensity to take their preferred action) and density (i.e., the expected width of social groups within the community).We discover that majority‐explorer teams are to be preferred when complexity is high and over the long run, whereas majority‐exploiter teams are more effective in the short run and at low complexities. Furthermore, we show that higher levels of specialization yield better results at higher complexities, and that majority‐explorer teams benefit the most from higher levels of density. We conclude that different team compositions are to be preferred at different stages of maturity, and that selecting a time horizon for operations is of crucial importance when designing an innovation team.
Enhanced membrane fouling control through self‐forming dynamic membrane and sponge‐wrapped membrane: A novel membrane bioreactor
Authors: Nagalakshmi S. , Mohan S. Mariraj 
Published: April 2023

AbstractMembrane technology offers a wide variety of advantages in wastewater treatment, but fouling impedes its widespread applications. Hence, in this study, a novel method was tried to control membrane fouling by combining the self‐forming dynamic membrane (SFDM) with a sponge‐wrapped membrane bioreactor. The configuration is termed a “Novel‐membrane bioreactor” (Novel‐MBR). To compare the performance of Novel‐MBR, a conventional membrane bioreactor (CMBR) was operated under similar operating conditions. CMBR and Novel‐MBR were run consequently for 60 and 150 days, respectively. The Novel‐MBR was composed of SFDMs in two compartments before a sponge‐wrapped membrane in the membrane compartment. In Novel‐MBR, the formation times for SFDMs on coarse (125 μm) and fine (37 μm) pore cloth filers were 43 and 13 min, respectively. The CMBR experienced more frequent fouling; the maximum fouling rate was 5.83 kPa/day. In CMBR, the membrane fouling due to cake layer resistance (6.92 × 1012 m−1) was high, and that alone contributed to 84% of fouling. In Novel‐MBR, the fouling rate was 0.0266 kPa/day, and the cake layer resistance was 0.329 × 1012 m−1. Also, the Novel‐MBR experienced 21 times less reversible fouling and 36 times less irreversible fouling resistance than the CMBR. In Novel‐MBR, the formed SFDM and the sponge wrapped on the membrane helped to reduce both reversible and irreversible fouling. With the modification tried in the present study, the Novel‐MBR experienced less fouling, and the maximum transmembrane pressure at the end of 150 days of operation was 4 kPa.Practitioner Points
CMBR experienced frequent fouling, and the maximum fouling rate was 5.83 kPa/day.
Cake layer resistance was dominant in CMBR and contributed to 84% of fouling.
The fouling rate of Novel‐MBR at the end of the operation was 0.0266 kPa/day.
Novel‐MBR is expected to perform for ≈3380 days to reach the maximum TMP of 35 kPa.
Analysis of Fast Power Reduction System for CPR1000 Nuclear Power Plants
Authors: Cheng Yanhua , Wang Kai , Xu Xingxing , Mao Yulong , Hu Yousen 
Published: April 2023

AbstractCPR1000 nuclear power plants have the risk of reactor trip during the house load and turbine trip transients. Rapid power reduction system of AP1000 nuclear power plants and fast power setback system for VVER nuclear power plants are designed respectively, which can avoid this problem and thus provide more availability of units. It is necessary to introduce the Fast Power Reduction system to CPR1000 units to get more economy and flexibility. Based on the core control mode of CPR1000 units, the rod control assembly banks are regrouped to realize the fast power reduction function. Besides, the impact of fast power reduction system on the normal transients are evaluated. The results show that more operational margin can be released, and also the capacity of turbine bypass system can be reduced. Finally, more availability and economy can be obtained for CPR1000 units.
Application of MC-MC Coupled Method in Neutron Shielding Analysis of Reactor Pit in Reactor Building
Authors: Zeng Guanghao , Huang Qianqian , Yang Shouhai , Zhou Yonghai , Xiong Jun 
Published: April 2023

AbstractAs one of the areas with highest radiation risk in nuclear power plant with neutron and gamma ray radiation emitted from the reactor core, the reactor pit in reactor building has great radiation impact on personnel radiation safety by neutron. In order to further improve the shielding design effort of reactor pit, the MC-MC coupled method is developed. By applying the MCNP code and SuperMC code, the variance of the effective dose rate and thermal neutron flux inside the reactor pit is lower than 5% by consuming 6.7 h. The result shows that the MC-MC coupled method can effectively solve neutron shielding problem in large scale or in complex space.
Preparation and Shielding Performance of Gamma Ray Shielding Composite Materials Based on 3D Printing Technology
Authors: Li Yulong , Li Chengxin , Jiang Danfeng , Liu Feng , Liu Xiajie , Li Li 
Published: April 2023

AbstractExcessive gamma-rays will be emitted when a nuclear power plant is under the refueling overhaul, leading to a certain number of hotspots. To meet the shielding requirements of these hotspots of complex components, a nylon-tungsten shielding composite material was developed by laser selective sintering 3D printing technology. The effects to shielding performance of 3D printing shielding materials were emphatically studied for two preparation processes (including mechanical mixing method and coating method) of 3D printing composite powders. Experimental results show that the nylon-tungsten shielding composite material with tungsten content of 70–85% was obtained by 3D printing technology, which realizes the manufacture of mold-free customized and bonded shielding materials. The shielding material prepared by 3D printing technology by coating method is better than that by mechanical mixing method in shielding performance. When the mass ratio of tungsten powders is 80%, the linear attenuation coefficient can reach 0.32, which is the best formula of the composite material and can be used for shielding of complex components. All these results lay a theoretical foundation for the engineering application of 3D printing shielding materials.
Effects of Inlet Conditions on the Two-Phase Flow Water Hammer Transients in Elastic Tube
Authors: Zhao Zixiang , Duan Zhongdi , Xue Hongxiang , Yuan Yuchao , Liu Shiwen 
Published: April 2023

AbstractTwo-phase flow water hammer events occur in the pipelines of the nuclear power systems and lead to transient and violent pressure shock to tube structures. For the sake of operation safety, the occurrence and severity of the two-phase water hammer should be carefully assessed. This paper presents a parameter analysis of the inlet conditions on the two-phase flow water hammer transients, with considering the elastic effect of the tube walls. A numerical model is established for the vapor-liquid two-phase flow based on the two-fluid six-equation modelling approach, with incorporating correlations and criterions for two-phase flow regime, interfacial interactions and heat transfer. The governing equations are transformed to matrix form expressed by characteristic variables, and solved using the splitting operator method and the total variation diminishing scheme. The accuracy of the model is verified against the experimental data in open literature. Then, the model is applied to investigate the effect of inlet velocity and inlet water temperature on the two-phase flow water hammer transients. The simulation results show that the increase of inlet velocity increases the pressure peak values and brings forward the onset of water hammer, and the increase of inlet temperature decreases the pressure shock. A comparison of the water hammer results between the elastic tube and rigid tube is further presented, and the effect of the elastic modulus on the water hammer is analyzed. The results also show that the pressure peak is largely affected by the tube diameter.
Study on Coupling Effect and Dynamic Behavior of Double Bubbles Rising Process
Authors: Gong Lanxin , Peng Changhong , Zhang Zhenze 
Published: April 2023

AbstractGas-liquid two-phase flow widely exists in nuclear energy engineering, in which bubble movement and deformation are critical problems. Because the activity of bubbles in the fluid is a very complex physical process, and the movement process is a flow field-bubble coupling process, which has strong nonlinearity and unsteady, the relevant research is usually based on experiments and simulation.We built a medium-sized experimental device to generate double bubbles with different sizes and characteristic numbers and recorded the motion trajectory with a high-speed camera. We developed and improved the image processing method to obtain high-quality bubble motion information and realized a good capture of bubble shape and rotation.The experimental results show that in the two bubbles rising successively, the trailing bubble is affected by the trailing field of the leading bubble, and the bubble velocity, relative distance, deformation rate, and other parameters change accordingly. In addition, through simulation, we get the interaction mechanism of the bubbles under experimental conditions. The results show that the coupling leads to flow field velocity and pressure changes, which explains the experimental results. The research results are helpful for a thorough understanding of the law of bubble movement and provide empirical data support for developing a thermal-hydraulic model.
Automatisierte, randomisierte Online-Programmierprüfung mit geringem, kurzzeitigem Datenverkehr
Authors: Beckmann Nils 
Published: April 2023

ZusammenfassungDie Möglichkeit zur Teilnahme an Online-Prüfungen ist generell bedingt durch die Stabilität und Geschwindigkeit der Internetverbindung der Prüfungsteilnehmer sowie die Zuverlässigkeit der Computer und Server, über welche die Prüfung bereitgestellt wird. Insbesondere bei großen Teilnehmerzahlen können hohe Serverlasten zu Beginn und Ende der Prüfung auftreten, wenn viele Teilnehmer zur selben Zeit größere Dateien herunter- oder hochladen. Im Folgenden wird eine Prüfungsmethode vorgestellt, die diese beiden Hürden für eine Prüfungsteilnahme reduziert. Hierbei sind die zu übertragenden Datenmengen gering, betragen insgesamt weniger als ein halbes Megabyte je Teilnehmer und müssen nur zu Beginn und Ende der Prüfung einmalig übermittelt werden. Die Prüfungsmethode eignet sich insbesondere für Programmierprüfungen, ist aber auch für andere Fachgebiete anwendbar. Es stehen verschiedene Fragentypen zur Auswahl. Die Aufgaben werden zufällig auf die Teilnehmer verteilt, können lokal bearbeitet sowie anschließend größtenteils automatisiert korrigiert und ausgewertet werden.
Can gadolinium contrast agents be replaced with saline for direct MR arthrography of the hip? A pilot study with arthroscopic comparison
Authors: Meier Malin K. , Wagner Moritz , Brunner Alexander , Lerch Till D. , Steppacher Simon D. , Vavron Peter , Schmaranzer Ehrenfried , Schmaranzer Florian 
Published: April 2023

Abstract
Objective
To compare image quality and diagnostic performance of preoperative direct hip magnetic resonance arthrography (MRA) performed with gadolinium contrast agent and saline solution.

Methods
IRB-approved retrospective study of 140 age and sex-matched symptomatic patients with femoroacetabular impingement, who either underwent intra-articular injection of 15–20 mL gadopentetate dimeglumine (GBCA), 2.0 mmol/L (“GBCA-MRA” group, n = 70), or 0.9% saline solution (“Saline-MRA” group, n = 70) for preoperative hip MRA and subsequent hip arthroscopy. 1.5 T hip MRA was performed including leg traction. Two readers assessed image quality using a 5-point Likert scale (1–5, excellent-poor), labrum and femoroacetabular cartilage lesions. Arthroscopic diagnosis was used to calculate diagnostic accuracy which was compared between groups with Fisher’s exact tests. Image quality was compared with the Mann–Whitney U tests.

Results
Mean age was 33 years ± 9, 21% female patients. Image quality was excellent (GBCA-MRA mean range, 1.1–1.3 vs 1.1–1.2 points for Saline-MRA) and not different between groups (all p > 0.05) except for image contrast which was lower for Saline-MRA group (GBCA-MRA 1.1 ± 0.4 vs Saline-MRA 1.8 ± 0.5; p < 0.001). Accuracy was high for both groups for reader 1/reader 2 for labrum (GBCA-MRA 94%/ 96% versus Saline-MRA 96%/93%; p > 0.999/p = 0.904) and acetabular (GBCA-MRA 86%/ 83% versus Saline-MRA 89%/87%; p = 0.902/p = 0.901) and femoral cartilage lesions (GBCA-MRA 97%/ 99% versus Saline-MRA 97%/97%; both p > 0.999).

Conclusion
Diagnostic accuracy and image quality of Saline-MRA and GBCA-MRA is high in assessing chondrolabral lesions underlining the potential role of non-gadolinium-based hip MRA.

Key Points
• Image quality of Saline-MRA and GBCA-MRA was excellent for labrum, acetabular and femoral cartilage, ligamentum teres, and the capsule (all p > 0.18).
• The overall image contrast was lower for Saline-MRA (Saline-MRA 1.8 ± 0.5 vs. GBCA-MRA 1.1 ± 0.4; p < 0.001).
• Diagnostic accuracy was high for Saline-MRA and GBCA-MRA for labrum (96% vs. 94%; p > 0.999), acetabular cartilage damage (89% vs. 86%; p = 0.902), femoral cartilage damage (97% vs. 97%; p > 0.999), and extensive cartilage damage (97% vs. 93%; p = 0.904).
Die Biomechanik der Hornhaut vor und nach Crosslinking bei Patienten mit Keratokonus
Authors: Feld S. , Flockerzi E. , Daas L. , Xanthopoulou K. , Sideroudi H. , Langenbucher A. , Seitz B. 
Published: April 2023

Zusammenfassung
Fragestellung
Ziel dieser Studie war es, den Effekt des kornealen Crosslinking (CXL) auf die Biomechanik der Hornhaut und den Visus zu analysieren.

Patienten und Methoden
Die Untersuchungsergebnisse vor und nach CXL an 56 Augen von 56 Patienten zwischen 2017 und 2021 wurden retrospektiv ausgewertet. Es wurde die letzte präoperative Untersuchung mit den postoperativen Werten nach 6 bzw. 12 Monaten verglichen. Die untersuchten Zielgrößen umfassten verschiedene biomechanische Parameter aus Corvis ST (CST) und der Pentacam und den Visus (logMAR, „logarithm of the Minimal Angle of Resolution“, Logarithmus des minimalen Auflösungswinkel). Für die Auswertung von Längsschnittdaten wurde ein lineares Modell für wiederholte Messungen und für Mehrfachvergleiche eine Bonferroni-Korrektur angewendet. Das Signifikanzniveau lag bei 5 %.

Ergebnisse
Die maximale Hornhautbrechkraft Kmax reduzierte sich geringfügig ohne statistische Signifikanz von 57,1 ± 6,1 Dioptrien (dpt) auf 56,6 ± 6,3 dpt nach 6 Monaten (p = 0,076) und 56,8 ± 6,6 dpt nach 12 Monaten (p = 0,443). Der Pentacam-Parameter Belin/Ambrósio Enhanced Ectasia Total Deviation Display (BAD D) erhöhte sich vom präoperativen Wert 8,4 ± 3,7 nach 6 Monaten statistisch signifikant auf den postoperativen Wert 9,1 ± 3,6 (p < 0,001) und auf 8,9 ± 3,5 nach 12 Monaten (p = 0,051). Der CST-Parameter Ambrósio’s relational thickness to the horizontal profile (ARTh) verringerte sich statistisch signifikant von 229,9 ± 109,6 auf 204,8 ± 84,9 nach 6 Monaten (p = 0,017) und 205,3 ± 93,7 nach 12 Monaten (p = 0,022). Der CST-Parameter Stiffness Parameter A1 (SP A1) erhöhte sich geringfügig vom präoperativen Wert 69,9 ± 17,2 auf 70,4 ± 17,2 nach 6 Monaten (p = 1) und 71 ± 18,2 nach 1 Jahr (p = 1). Der mittlere bestkorrigierte cc-Visus (logMAR) zeigte eine Verbesserung von 0,39 ± 0,3 auf 0,34 ± 0,3 nach 6 Monaten (p = 0,286) und auf 0,31 ± 0,3 nach 12 Monaten (p = 0,077). Präoperativ wurden hinsichtlich der ABCD-Klassifikation die Parameter mit durchschnittlich A2B3C1D2 bestimmt. Sie zeigten nach 6 und 12 Monaten den gleichen Wert von A2B3C1D2.

Schlussfolgerungen
Korneales Crosslinking hat bei progredientem Keratokonus als komplikationsarme Therapiemöglichkeit das Potenzial, die Biomechanik der Hornhaut und den Visus positiv zu beeinflussen.