bluuebunny/crossref_metadata_2025 huggingface dataset:
Connection and alienation during the COVID‐19 pandemic: The narratives of four engineering students
Authors: McIntyre Brianna Benedict , Rohde Jacqueline , Clements Herman Ronald , Godwin Allison
Published: March 2023

Background

The COVID‐19 pandemic has highlighted, exacerbated, and caused many challenges within engineering education. At the same time, the pandemic provided opportunities for engineering educators to learn from forced change to promote strategic efforts to improve classroom engagement and connection to better support engineering students.

Purpose

We leveraged students' stories to discuss ways university administrators, faculty, and instructors can better support their students during times of global crisis and beyond the current pandemic.

Design/Method

We conducted longitudinal narrative interviews with four White women engineering students from different universities in their third and fourth years. The students were selected from a larger research project because their rich and reflective stories resonated with other participant narratives, the research team, and ongoing conversations about educating during and after the COVID‐19 pandemic. Through narrative inquiry, we constructed “restoryed” vignettes and identified patterns within the four students' distinctive stories by drawing on a theoretical framework designed to examine connection and alienation.

Results

The findings provided insights into how students were stressed and disconnected from their education in undesirable ways. The findings also provide insight into how those same students received support and maintained a connection to their institution, advisors, and instructors that educators could emulate.

Conclusions

Our theoretical framework of connection and alienation proved helpful for understanding the experiences of four engineering students. Additionally, these stories provide practical examples of how faculty and staff can support student connections beyond the pandemic.
A Malaysian consensus report on the diagnosis and treatment of Helicobacter pylori infection
Authors: Goh Khean‐Lee , Lee Yeong Yeh , Leow Alex Hwong‐Ruey , Ali Raja Affendi Raja , Ho Shiaw Hooi , Mahadeva Sanjiv , Mohd Said Rosaida Hj , Muthukaruppan Chettiar Raman , Tee Hoi Poh
Published: March 2023

Helicobacter pylori is one of the most common chronic bacterial infections in humans and responsible for 90% of duodenal ulcers and 70–90% of gastric ulcers. Despite this, many misconceptions regarding the appropriate diagnostic method and treatment strategies still exist in the Malaysian clinical practice. Under the initiative of the steering committee, an expert panel consisting of nine key opinion leaders in the field of gastroenterology convened to develop a set of consensus statements that are relevant to the Malaysian healthcare practice. The panel members reviewed the current evidence on the management of H. pylori infection, focusing on the best practices that are relevant to the Malaysian population based on clinical experience and published clinical evidence. Using the modified Delphi method, the panel achieved consensus in three areas of H. pylori infection management: indications for testing, diagnosis, and treatment. The panel proposed a set of 19 consensus statements, which were synthesized via two rounds of blinded voting and group discussions. The recommendations provided are relevant to the Malaysian population and can be used as a guide by physicians across various healthcare settings to facilitate appropriate diagnostic testing and treatment of H. pylori infection.
Comparing two durations of medically tailored meals posthospitalization: A randomized clinical trial
Authors: Boxer Rebecca , Drace Melanie L. , Kelly Cheryl , Robinson Rachael , Schwartz Pamela , Ausiello Jenna , Dollar Blythe , Paolino Valerie , Comer Angela , Powers John David , Steiner John F.
Published: March 2023

Background

Medically tailored meals (MTM) may be beneficial to patients after hospital discharge.

Objective

To determine if 2 versus 4 weeks of MTM posthospitalization will improve patient outcomes.

Design

Randomized unblinded trial.

Settings and Participants

Six hundred and fifty patients pending hospital discharge with at least one chronic condition.

Intervention

One MTM a day for 2 versus 4 weeks.

Main Outcome and Measures

The primary outcome was a change from baseline to 60 days in the Hospital Anxiety Depression Scale (HADS). Secondary outcomes measured change in the Katz activities of daily living (ADLs), DETERMINE nutritional risk, and all‐cause emergency department (ED) visits and rehospitalizations.

Results

From baseline to 60 days the HADS anxiety subscale changed 5.4–4.9 in the 2‐week group (p = .03) and 5.4–5.3 in the 4‐week group (p = .49); the difference in change between groups 0.4 (p = .25). HADS changed 5.4–4.8 in the 2‐week group (p = .005) and 5.3–5.1 in the 4‐week group (p = .34); the difference in change between groups 0.4 (p = .18). ADL score changed from 5.3 to 5.6 in the 2‐week group (p ≤ .0001) and 5.2–5.5 in the 4‐week group (p ≤ .0001); the difference in change between groups −0.01 (p = .90). The DETERMINE changed in the 2‐week group from 7.2 to 6.4 (p = .0006) and from 7 to 6.7 in the 4‐week group (p = .19); the difference in change between groups 0.5 (p = .13). There was no difference in ED visits and rehospitalizations between groups or time to rehospitalization.

Conclusions

Different durations of short‐term MTM did not affect patient‐centered or utilization outcomes.
Leaders' political skills and organizational change
Authors: Ouedraogo Noufou , Ouakouak Mohammed Laid , Hewapathirana Gertrude I.
Published: March 2023

We studied the impact of leaders’ political skill on employee support for organizational change and the effect of the latter on change fatigue and change outcomes. Drawing from the theoretical characterization of the political skill construct domain proposed by Ferris et al. (2007), we posited that leaders’ political skill during organizational change plays an important role in garnering employee support for change and, ultimately, in achieving positive change outcomes. To conduct the study, we used survey data collected through SurveyMonkey on 197 participants working in Canadian organizations and used structural equation modeling techniques to analyze the data. We found that two dimensions of leaders’ political skill—their networking ability and apparent sincerity—positively affected employee support for change, which, in turn, positively affected change outcomes. However, neither of the other two dimensions examined (interpersonal influence and social astuteness) had a significant relationship with employee support for change. We also found that employee support for change and change fatigue were not significantly related, although change fatigue itself negatively affected change outcomes. From a theoretical perspective, this study is among the first to empirically test and confirm the impact of different dimensions of leaders’ political skill on employees’ change support. We also contribute theoretical knowledge by showing the detrimental effect of change fatigue on change outcomes. From a practical perspective, our findings imply that change leadership roles should be assigned to people who exhibit networking skills and apparent sincerity. Moreover, change leaders should prioritize seeking and securing employees’ support for change.
Entrepreneurship: Definitions, opportunities, challenges, and future directions
Authors: Ratten Vanessa
Published: March 2023

Entrepreneurship as a field of study has many sub‐dimensions due to its usefulness in society, which makes it difficult to gain a holistic understanding of its key elements. The aim of this article is to explore how to define entrepreneurship by focusing on different areas of entrepreneurship in terms of definitions and research opportunities in order to challenge conventional practices. Each area of entrepreneurship is discussed with the goal of exploring new research questions and methodological approaches that are currently lacking in the entrepreneurship discourse and can be refined through future research activity. This enables future research directions to be identified regarding entrepreneurship in general and specific types of entrepreneurship thereby contributing to research and practice about the importance of entrepreneurship in society.
Hospital and surgeon experience and patient health outcomes after coronary artery bypass graft surgery
Authors: Li Jingyun , Bardhan Indranil R. , Sethi Suresh , Ring W. Steves
Published: March 2023

The Hospital Readmissions Reduction Program imposes financial penalties on hospitals with excess readmission rates for various conditions, including coronary artery bypass graft (CABG) surgery. While prior research has focused mainly on hospital‐specific factors and their impact on patient mortality, surgeon risk factors and patient outcomes, such as readmission risk, have received less attention. We study three drivers of CABG readmission risk—hospital and surgeon case volume, variation in surgeon volume, and surgeon familiarity with hospitals. Drawing on unique patient data sets of CABG surgeries spanning 3 years, we study the relationships between hospital and surgeon case volume, readmission risk, and postoperative length of stay (PLOS). We find evidence of an inverted U‐shaped relationship between case volume and readmission risk and a U‐shaped relationship with PLOS. Our results also indicate that surgeon volume variation moderates the relationship between surgeon volume and readmission risk, where readmission risk increases with greater variation in surgeon volume. We observe that the impact of surgeon experience on readmission risk at the focal hospital outweighs their experience at other hospitals. Our study has significant implications for hospital resource management as it highlights the role of surgeon and hospital experience in improving patient outcomes after CABG surgery.
Integrated non‐targeted and targeted metabolomics analysis reveals the mechanism of inhibiting lignification and optimizing the quality of pea sprouts by combined application of nano‐selenium and lentinans
Authors: Lin Yongxi , Zhou Chunran , Li Dong , Wu Yangliu , Dong Qinyong , Jia Yujiao , Yu Huan , Miao Peijuan , Pan Canping
Published: March 2023

BACKGROUND

Lignification causes a detrimental impact on the quality of edible sprouts. However, the mechanism of inhibition of lignification of edible sprouts by nano‐selenium and lentinans remains unclear.

RESULTS

To reveal the mechanism of lignification regulation of sprouts by nano‐selenium and lentinans, this study investigated the changes in antioxidant indicators, phytohormones, polyphenols, and metabolites in the lignin biosynthesis in pea sprouts following sprays of nano‐selenium or/and lentinans twice. There was an overall increase in the aforementioned indices following treatment. In particular, the combined application of 5 mg L−1 nano‐selenium and 20 mg L−1 lentinans was more effective than their individual applications in enhancing peroxidase, catalase, DPPH free‐radical scavenging rate, luteolin, and sinapic acid, as well as inhibiting malondialdehyde generation and lignin accumulation. Combined with the results from correlation analysis, nano‐selenium and lentinans may inhibit lignification by enhancing antioxidant systems, inducing phytohormone‐mediated signaling, and enriching precursor metabolites (caffeyl alcohol, sinapyl alcohol, 4‐coumaryl alcohol). In terms of the results of non‐targeted metabolomics, the combined application of 5 mg L−1 nano‐selenium and 20 mg L−1 lentinans mainly affected biosynthesis of plant secondary metabolites, biosynthesis of phenylpropanoids, phenylpropanoid biosynthesis, arginine and proline metabolism, and linoleic acid metabolism pathways, which supported and complemented results from targeted screenings.

CONCLUSION

Overall, the combined sprays of nano‐selenium and lentinans showed synergistic effects in delaying lignification and optimizing the quality of pea sprouts. This study provides a novel and practicable technology for delaying lignification in the cultivation of edible sprouts. © 2023 Society of Chemical Industry.
Treatment and survival of patients with malignant ovarian sex cord‐stromal cell tumours: An analysis of the Arbeitsgemeinschaft für Gynäkologische Onkologie (AGO) study group CORSETT database
Authors: Klar Maximilian , Plett Helmut , Harter Philipp , Heitz Florian , Kommoss Stefan , Hartkopf Andreas Daniel , Grube Marcel , Roser Eva , Sehouli Jalid , Braicu Iona , Czogalla Bastian , Burges Alexander , Bossart Michaela , Hasanov Mir Fuad , Link Teresa , Staebler Annette , Mayr Doris , Buderath Paul , Hasenburg Annette
Published: March 2023

Background

Malignant sex cord‐stromal cell tumours (SCST) account for only 7% of ovarian malignancies. The Arbeitsgemeinschaft fuer Gynaekologische Onkologie (AGO) study group has established a clinicopathological database to provide an overview of the current treatment strategies and survival of SCST patients and to identify research needs.

Methods

Twenty centres provided mixed retro‐ and prospective data of patients with tumour specimens and second‐opinion pathology review treated between 2000 and 2014. Descriptive analyses of treatment strategies, Kaplan–Meier curves and cox regression analyses were conducted.

Results

Two hundred and sixty‐two SCST patients were included. One hundred and ninety‐one Granulosa‐cell tumour (GCT) and 17 Sertoli‐Leydig cell tumour (SLCT) patients were stage I disease (>80%). Forty four GCT (18.7%) and two (8.3%) SLCT patients received adjuvant systemic treatment. After a median observation time of 78.2 months, 46% of all SCST patients experienced disease recurrence, treated predominantly with secondary debulking surgery (> 90%). Advanced FIGO stage, lymph node involvement and intra‐operative capsule rupture were associated with disease recurrence on univariate analysis (all p < 0.05). Median OS time was not reached.

Discussion

In this analysis of SCST patients, adjuvant chemotherapy was unable to prevent disease recurrence. Despite high recurrence rates, overall survival rates were excellent.
Simultaneous quantitation of 17 female sex hormones in illegal products by validated liquid chromatography‐high resolution mass spectrometry and liquid chromatography‐tandem mass spectrometry methods
Authors: Lee Ji Hyun , Seo Min Kyeong , Ham Hyeon Joo , Seo Sowoon , Shin Dongwoo , Kim Hyung Il
Published: March 2023

The consumption of food and drugs adulterated with female sex hormones can have an extremely adverse effect on human health. Therefore, developing appropriate monitoring methods for the identification of various exogenous female sex hormones is crucial for minimizing and eliminating the related health risks. Herein, 17 female hormones categorized into two groups: estrogen and progestin, were analyzed using reversed‐phase liquid chromatography coupled to Orbitrap or triple quadrupole mass spectrometry. The fragmentation patterns for all compounds were discovered, and fragmented structures were also derived from them through liquid chromatography–high‐resolution mass spectrometry followed by qualitative sample analysis. In addition, a quantitative analysis of 67 samples of illicit drugs and dietary supplements was performed using the validated liquid chromatography‐tandem mass spectrometry method. Female hormone components were detected in two samples of an unauthorized injectable solution and a tablet‐type drug. Medroxyprogesterone was detected in the samples in the range of 96.4–206 ng/g. Notably, eight components similar in structure to steroids were simultaneously detected as male sex hormones by confirming their fragmentation ion patterns using liquid chromatography–high‐resolution mass spectrometry. The developed methods thus offer a dependable and practically applicable approach for the screening and detection of exogenous female sex hormones in real food and drug samples to ensure public health.
Geographic variation in organic carbon storage by seagrass beds
Authors: McHenry Jennifer , Rassweiler Andrew , Hernan Gema , Dubel Alexandra K. , Curtin Carolyn , Barzak Jakob , Varias Nicholas , Lester Sarah E.
Published: March 2023

Since seagrasses are efficient sinks for marine organic carbon, there is growing interest in incorporating seagrass protection and restoration into climate mitigation schemes, that is, offering credit for accumulated carbon to offset carbon dioxide emissions. However, patterns and drivers of organic carbon storage by seagrasses are not well resolved, especially at scales relevant to management decisions. Here, we quantified geographic variation in standing stocks of sedimentary organic carbon (Mg Corg ha−1) associated with seagrasses along the northern Florida Gulf Coast using field surveys and sediment cores. We measured plant biomass, organic carbon, and sediment composition in each core. Using a multivariate modeling approach, we evaluated the relative importance of ecological, physical, oceanographic, and seascape drivers, developing the first spatially explicit predictions of seagrass‐associated carbon stocks for this region. Applying model predictions to confirmed seagrass beds and potential recovery areas, we also estimated the carbon storage value of potential seagrass conservation and restoration as the resulting stock enhancement value per hectare of seagrass (Δ Mg Corg ha−1). We found that organic carbon stored by seagrass sediments varied considerably across this region, with stocks significantly increasing with seagrass cover, proximity to oyster reefs, and distance from river outlets, highlighting potential synergies for coordinated management. We also found that current seagrass beds could offer nearly double the carbon storage value of potential recovery areas, emphasizing the importance of conservation as well as restoration. Our results have important implications for management, restoration, and understanding biogeographic patterns of seagrass ecosystem services.
Development and In Vivo Assessment of an Injectable Cross‐Linked Cartilage Acellular Matrix‐PEG Hydrogel Scaffold Derived from Porcine Cartilage for Tissue Engineering
Authors: Ju Hyeon Jin , Ji Yun Bae , Kim Shina , Yun Hee‐Woong , Kim Jae Ho , Min Byoung Hyun , Kim Moon Suk
Published: March 2023

The cartilage acellular matrix (CAM) derived from porcine cartilage, which does not induce significant inflammation and provides an environment conducive for cell growth and differentiation, is a promising biomaterial candidate for scaffold fabrication. However, the CAM has a short period in vivo, and the in vivo maintenance is not controlled. Therefore, this study is aimed at developing an injectable hydrogel scaffold using a CAM. The CAM is cross‐linked with a biocompatible polyethylene glycol (PEG) cross‐linker to replace typically used glutaraldehyde (GA) cross‐linker. The cross‐linking degree of cross‐linked CAM by PEG cross‐linker (Cx‐CAM‐PEG) according to the ratios of the CAM and PEG cross‐linker is confirmed by contact angle and heat capacities measured by differential scanning calorimetry. The injectable Cx‐CAM‐PEG suspension exhibits controllable rheological properties and injectability. Additionally, injectable Cx‐CAM‐PEG suspensions with no free aldehyde group are formed in the in vivo hydrogel scaffold almost simultaneously with injection. In vivo maintenance of Cx‐CAM‐PEG is realized by the cross‐linking ratio. The in vivo formed Cx‐CAM‐PEG hydrogel scaffold exhibits certain host–cell infiltration and negligible inflammation within and near the transplanted Cx‐CAM‐PEG hydrogel scaffold. These results suggest that injectable Cx‐CAM‐PEG suspensions, which are safe and biocompatible in vivo, represent potential candidates for (pre‐)clinical scaffolds.
Long‐term cathodic disbondment tests in three‐layer polyethylene coatings
Authors: de Freitas Denise S. , Brasil Simone L. D. C. , Leoni Gabriel , Motta Gustavo X. da , Leite Eduardo G. B. , Coelho Jorge F. P.
Published: March 2023

Cathodic protection allied to a polymeric coating is one of the most employed techniques to protect buried steel pipelines against corrosion. Nevertheless, cathodic disbondment, a phenomenon associated with such protection in high‐performance coatings such as (three‐layer polyethylene [3LPE]), still concerns the oil and gas segment regarding pipeline integrity. The present work was part of a Program of Integrity Management and studied in field‐like conditions the influence of cathodic potential, type of soil and coating system on the coating disbondment of buried pipelines for 450 days. The coating systems herein studied simulated the patching between aged (coal tar) and new coatings (3LPE), a standard procedure during damaged pipeline repair. Results pointed out that the combination between aged (coal tar) and new coatings (3LPE) in a pipe segment reduced coating disbondment when compared to the systems where 3LPE was the sole type of coating. Moreover, it was shown that more cathodic potentials (<−1100 mV) and the aggressiveness of the industrial soil herein tested induced disbondment diameters as high as 15.5 mm.
Long‐term atmospheric corrosion of Cr‐free painted aluminum alloys during outdoor worldwide exposures
Authors: Peltier Fabienne , Thierry Dominique
Published: March 2023

Cr‐free paints applied on different aluminum alloys were exposed for 5 years at different atmospheric weathering sites worldwide. By image analysis, the extent, and the type of corrosion (filiform or blistering) were determined after 1, 2, and 5 years. In that way, it was possible to rank the different systems as a function of their resistance to corrosion. The kinetics of degradation of each system at all sites was also determined. From the results, it is shown that the kinetics of degradation is system dependent. It is also shown that it is the combination of several climatic parameters which contributes to the corrosivity of the site and not only one single parameter such as chloride deposition, relative humidity, and so on.
Nonaqueous magnetization following adiabatic and selective pulses in brain: T1 and cross‐relaxation dynamics
Authors: Reynolds Luke A. , Morris Sarah R. , Vavasour Irene M. , Barlow Laura , Laule Cornelia , MacKay Alex L. , Michal Carl A.
Published: March 2023

Inversion pulses are commonly employed in MRI for
‐weighted contrast and relaxation measurements. In the brain, it is often assumed that adiabatic pulses saturate the nonaqueous magnetization. We investigated this assumption using solid‐state NMR to monitor the nonaqueous signal directly following adiabatic inversion and compared this with signals following hard and soft inversion pulses. The effects of the different preparations on relaxation dynamics were explored. Inversion recovery experiments were performed on ex vivo bovine and porcine brains using 360‐MHz (8.4 T) and 200‐MHz (4.7 T) NMR spectrometers, respectively, using broadband rectangular, adiabatic, and sinc inversion pulses as well as a long rectangular saturation pulse. Analogous human brain MRI experiments were performed at 3 T using single‐slice echo‐planar imaging. Relaxation data were fitted by mono‐ and biexponential decay models. Further fitting analysis was performed using only two inversion delay times. Adiabatic and sinc inversion left much of the nonaqueous magnetization along
and resulted in biexponential relaxation. Saturation of both aqueous and nonaqueous magnetization components led to effectively monoexponential
relaxation. Typical adiabatic inversion pulses do not, as has been widely assumed, saturate the nonaqueous proton magnetization in white matter. Unequal magnetization states in aqueous and nonaqueous 1H reservoirs prepared by soft and adiabatic pulses result in biexponential
relaxation. Both pools must be prepared in the same magnetization state (e.g., saturated or inverted) in order to observe consistent monoexponential relaxation.
Collagen cross‐linking in oral cancer
Authors: Uzawa Katsuhiro , Kasamatsu Atsushi , Yamauchi Mitsuo
Published: March 2023

Carcinogenesis is widely recognized to be caused by qualitative and quantitative genetic changes. These changes include abnormalities in gene structure itself and/or in transcriptional mechanisms involved in gene expression in cancer cells and cancer‐associated cells. Emerging evidence has also revealed that the nature of the extracellular matrix (ECM) in the tumor microenvironment actively regulates cancer cell growth, migration, and metastasis. The most abundant protein in the ECM surrounding cancer cells is fibrillar type I collagen that accumulates and stiffens through formation of specific types of covalent intermolecular cross‐links. Alterations in the physicochemical nature of ECM proteins like fibrillar type I collagen can affect cancer cell behavior. This review provides an overview of collagen cross‐linking and its roles in oral cancer as well as possible clinical applications.
Development and validation of the Scale of Emotional Functioning: Education (SEF:ED)
Authors: Anderson Lezli Suzanne , McCallum R. Steve , Castleman David M. , Fast Michelle
Published: March 2023

Data collected from 97 educators provide preliminary support for the psychometric integrity of an experimental self‐report instrument designed to operationalize emotional intelligence (EI) specifically for educators, the Scale of Emotional Functioning: Educators, or SEF:ED. Data analyses relied in part on results from an exploratory factor analysis, which provided evidence for a three‐factor solution, and additional correlational analyses (e.g., item‐scale correlations). Reliability estimates (i.e., split‐half reliability correlations) for the SEF:ED Emotional Awareness, Emotional Management, and Interpersonal Relations subscales are .86, .80, and .71, respectively. Correlation coefficients (i.e., Pearson r) between the SEF:ED composites and the Profile of Emotional Competence composites (PEC) range from .35 to .72, providing evidence for concurrent validity of the SEF:ED. Finally, correlation coefficients between SEF:ED and the Maslach Burnout Inventory for Educators (MBI‐ES) range from −.21 to .59 and provide limited evidence of its ability to predict an important work site characteristic, that is, burnout. Once the SEF:ED was completed, descriptive statistics were obtained for EI and burnout and show relatively similar means/standard deviations across various demographics (e.g., gender, educator degree, years in service, and classroom setting—general vs. special education). Limitations of the study and implications for application of the SEF:ED are discussed.
Preparation and characterization of superfine spherical TKX‐50 with a hollow structure by spray drying
Authors: Wang Shiwen , Zong Huzeng , Yang Cao , Hao Gazi , Zhang Guangpu , Yang Junqing , Feng Xiaojun , Zhang Kun , Zhang Tianfu , Xiao Lei , Jiang Wei
Published: March 2023

Micro/nano energetic materials with regular morphologies exhibit high energy release efficiency, superior charge performance, and low mechanical sensitivity. Exploring dihydroxylammonium 5,5′‐bistetrazole‐1,1′‐diolate (TKX‐50) with spherical microstructures and excellent comprehensive properties is of great significance for potential applications. In this work, a kind of superfine spherical TKX‐50 was fabricated by spray drying method. The as‐prepared TKX‐50 had a narrow particle size distribution with d50=3.14 μm, high sphericity of 0.944 with hollow structure and bulk density of 1.851 g/cm3. And its formation mechanism was proposed. The results of XRD and FT‐IR demonstrated that spray drying would not change the crystal structure of TKX‐50. TG‐DSC results showed that the initial decomposition and the peak temperature of superfine spherical TKX‐50 was about 10 °C lower than raw TKX‐50, and the apparent activation energy was 4.584 kJ ⋅ mol−1 lower than raw TKX‐50, due to the dramatic change in morphology. TG‐DSC‐FTIR‐MS provided a new understanding of decomposition process of TKX‐50, and the results illustrated that the main gas products were N2, H2O, N2O, NH3, NO, NH2, CO2, and HCN. Superfine spherical TKX‐50 underwent similar decomposition path as raw TKX‐50 but stood out in its larger occupation of the first decomposition which meant a more complete decomposition and its faster rate of the whole decomposition process. More importantly, the impact sensitivity (H50) increased from 50.1 cm to 70.8 cm, and the friction sensitivity (P) decreased from 24 % to 0 %, showing improved safety performance.
Thermal isomerization of phenylazoindoles: Inversion or rotation? That is the question
Authors: Hegedüsová Lea , KuteI' Rastislav , Medved' Miroslav , Pašteka Lukáš Félix , Cigáň Marek , Budzák Šimon
Published: March 2023

Azoheteroarenes represent an attractive group of photochromes exhibiting a large structural variability and tunability of photoswitching characteristics. The thermal back‐isomerization can proceed via inversion or rotation mechanisms, depending on the functionalization and environment. However, the distinction between the two remains a challenge for both experiment and theory. Here, four experimentally fully characterized phenylazoindoles are studied to establish the mechanism of back‐reaction in solvent using density functional theory (DFT), spin‐flip time‐dependent (TD‐)DFT, mixed‐reference TD‐DFT, and restricted ensemble Kohn–Sham approaches as well as CASPT2 and CCSD(T). While the inversion is consistently described by all methods, the rotation mechanism requires multireference approaches including dynamic correlation. The balanced description of both pathways becomes even more important in solvent which apparently affects the mechanism. For the present set, the range‐separated functionals combined with continuum models appear to be the most consistent with experiment in terms of the substitutional and solvent effects on thermal halftimes.
Pitfalls of the concordance index for survival outcomes
Authors: Hartman Nicholas , Kim Sehee , He Kevin , Kalbfleisch John D.
Published: March 2023

Prognostic models are useful tools for assessing a patient's risk of experiencing adverse health events. In practice, these models must be validated before implementation to ensure that they are clinically useful. The concordance index (C‐Index) is a popular statistic that is used for model validation, and it is often applied to models with binary or survival outcome variables. In this paper, we summarize existing criticism of the C‐Index and show that many limitations are accentuated when applied to survival outcomes, and to continuous outcomes more generally. We present several examples that show the challenges in achieving high concordance with survival outcomes, and we argue that the C‐Index is often not clinically meaningful in this setting. We derive a relationship between the concordance probability and the coefficient of determination under an ordinary least squares model with normally distributed predictors, which highlights the limitations of the C‐Index for continuous outcomes. Finally, we recommend existing alternatives that more closely align with common uses of survival models.
Highly Selective N2 Electroreduction to NH3 Using a Boron‐Vacancy‐Rich Diatomic NbB Catalyst
Authors: Feng Ru , Yin Hanqing , Jin Fuhao , Niu Wei , Zhang Wanting , Liu Jingquan , Du Aijun , Yang Wenrong , Liu Zhen
Published: March 2023

The ambient electrochemical N2 reduction reaction (NRR) is a future approach for the artificial NH3 synthesis to overcome the problems of high‐energy consumption and environmental pollution by Haber–Bosch technology. However, the challenge of N2 activation on a catalyst surface and the competitive hydrogen evolution reaction make the current NRR unsatisfied. Herein, this work demonstrates that NbB2 nanoflakes (NFs) exhibit excellent selectivity and durability in NRR, which produces NH3 with a production rate of 30.5 µg h−1 mgcat−1 and a super‐high Faraday efficiency (FE) of 40.2%. The high‐selective NH3 production is attributed to the large amount of active B vacancies on the surface of NbB2 NFs. Density functional theory calculations suggest that the multiple atomic adsorption of N2 on both unsaturated Nb and B atoms results in a significantly stretched N2 molecule. The weakened NN triple bonds are easier to be broken for a biased NH3 production. The diatomic catalysis is a future approach for NRR as it shows a special N2 adsorption mode that can be well engineered.
Efficient generation of valid test inputs for deep neural networks via gradient search
Authors: Jiang Zhouxian , Li Honghui , Wang Rui
Published: March 2023

The safety and robustness of deep neural networks (DNNs) are currently of great concern. Adequate testing is commonly an effective technique to ensure the software's trustworthiness. However, existing DNN testing methods generate many invalid test inputs, which inevitably brings increased computational overhead and reduces the efficiency of DNN testing. In this paper, we focus on testing task‐specific DNN and investigating diverse, valid and natural test input generation based on data augmentation techniques. Specifically, we propose AugTest, a DNN testing method based on stochastic optimization with momentum, searching for optimal compositions of data augmentation parameters to efficiently generate diverse and valid test inputs. Experimental results show that our proposed method can effectively explore the data manifold space and find valid test inputs with high diversity and naturalness. Compared with the best‐performing baseline, AugTest can generate more test inputs with more average diversity and less average time. Furthermore, the generated test inputs have competitive generalizability to DNNs with different structures. The test error rates exceed 70% when testing other DNN models performing similar tasks using the test inputs generated by AugTest. This implies that our method can produce more valid and generalized data to unveil DNNs' errors.
Simultaneous estimation of methyl paraben, propyl paraben, and Bisphenol A in the plasma of Indian pregnant women using liquid chromatography–tandem mass spectrometry
Authors: Pradhan Rajesh , Mishra Diksha , Dubey Sunil Kumar , Khadgawat Rajesh , Kachhawa Garima , Gupta Tarang , Taliyan Rajeev
Published: March 2023

A selective, rapid, and novel bioanalytical method was developed for the simultaneous determination of methyl paraben, propyl paraben, and Bisphenol A in human plasma with a calibration curve range of 1–100 ng/ml. This method included protein precipitation to ensure extraction along with clean‐up of the complex biometrics. The Chromatographic separation was done using an AccucoreTM aQ liquid chromatography column (Dim. 100×3, particle size: 2.6 µm) with the mobile phase of a mixture consisting of 0.1% formic acid in water: 0.1% formic acid in acetonitrile (03:97, v/v) at a flow rate of 0.300 ml/min. The developed liquid chromatography–tandem mass spectrometry method was further validated utilizing the United States Food and Drug Administration guidelines and all the validation requirements were found to be satisfactory. This proposed method was later successfully utilized to determine the level of the three endocrine‐disrupting compounds in the plasma samples obtained from Indian pregnant women. The results suggest that these women might have been exposed to parabens and Bisphenol A from the use of products such as pharmaceuticals, cosmetics, processed food, and the environment.
Recent Progress in Aqueous Zinc‐Ion Batteries: From FundamentalScience to Structure Design
Authors: Wang Tiantian , Zhang Yue , You Junhua , Hu Fang
Published: March 2023

Rechargeable aqueous zinc‐ion batteries (ZIB) sparked a considerable surge of research attention in energy storage systems due to its environment benignity and superior electrochemical performance. Up to now, less efforts to delve into mechanisms of zinc metal anode and their electrochemical performance. Zn metal anodes sustain thorny issues with Zn dendrite growth, hydrogen evolution reaction, and Zn corrosion irreversible byproduct formation, which results in low coulomb efficiency (CE) and poor cycle ability of the battery. Herein, we reveal the fundamental understanding of the above issue, outline four step, including mass transfer, desolvation process, charge transfer and Zn cluster formation. It can be clearly seen from reported strategies to promote Zn anode stability that deals with one or more steps, thereby boosting the understanding of the issues of Zn anodes and benefiting the rational design to surmount the issue. We also sum up advanced materials and structure design such as the design of the anode surface and internal structure, electrolyte strategies, and multifunctional separators. Finally, possible tactics and future innovation direction for Zn‐based batteries are proposed to achieve high performance aqueous Zinc‐ion batteries.
Literature Review
Authors: Lessky Franziska
Published: March 2023

Innerhalb der letzten zwanzig Jahre sind zahlreiche Studien – vor allem im Rahmen der soziologischen Bildungsforschung – entstanden, die sich mit Studierenden, die als erste innerhalb ihrer Familie oder ihres Umfeldes studieren, auseinandersetzen. Eine seit der Bildungsexpansion stark anwachsende Studierendenpopulation, der Versuch der Wohlstandssicherung durch die Erweiterung des Zugangs zu Bildung für bisher unterrepräsentierte oder benachteiligte Gruppen und die trotz politischer Maßnahmen diesbezüglich anhaltenden sozialen Ungleichheiten sind nur einige Gründe für das wachsende Interesse an Forschungen über sogenannte First-in-Family Studierende.
The epsilon expansion of the O(N) model with line defect from conformal field theory
Authors: Nishioka Tatsuma , Okuyama Yoshitaka , Shimamori Soichiro
Published: March 2023

Abstract

We employ the axiomatic framework of Rychkov and Tan to investigate the critical O(N) vector model with a line defect in (4 − ϵ) dimensions. We assume the fixed point is described by defect conformal field theory and show that the critical value of the defect coupling to the bulk field is uniquely fixed without resorting to diagrammatic calculations. We also study various defect localized operators by the axiomatic method, where the analyticity of correlation functions plays a crucial role in determining the conformal dimensions of defect composite operators. In all cases, including operators with operator mixing, we reproduce the leading anomalous dimensions obtained by perturbative calculations.
On (spinor)-helicity and bosonization in AdS4/CFT3
Authors: Skvortsov Evgeny , Yin Yihao
Published: March 2023

Abstract

Helicity is a useful concept both for AdS4 and CFT3 studies. We work out the complete AdS4/CFT3 dictionary for spinning fields/operators in the spinor-helicity base that allows one to scalarize any n-point contact vertex. AdS4-vertices encode correlation functions of conserved currents, stress-tensor and, more generally, higher spin currents in a simple way. We work out the dictionary for Yang-Mills- and gravity-type theories with higher derivative corrections as well as some higher spin examples and exemplify the relation to the three-dimensional bosonization duality. The bosonization can be understood as a simple surgery: vertices/correlators are built via an EM-duality transformation by sewing together (anti)-Chiral higher spin gravities, to whose existence the three-dimensional bosonization duality can be attributed (up to the proof of uniqueness).
Colliding localized, lumpy holographic shocks with a granular nuclear structure
Authors: Waeber Sebastian , Yaffe Laurence G.
Published: March 2023

Abstract

We apply a recent and simple technique which speeds up the calculation of localized collisions in holography to study more realistic models of the pre-hydrodynamic phase of heavy ion collisions using gauge/gravity duality. Our initial data reflects the lumpy nuclear structure of real heavy ions and our projectiles’ aspect ratio mimics the Lorentz contraction of nuclei during RHIC collisions. At the hydrodynamization time of the central region of the quark gluon plasma developed during the collision, we find that most of the system’s vorticity is located well outside the hydrodynamized part of the plasma. Only the relativistic corrections to the thermal vorticity within the hydrodynamized region are non-negligible. We compare the transverse flow shortly after the collision with previous results which did not use granular initial conditions and determine the proper energy density and fluid velocity in the hydrodynamized subregion of the plasma.
Light Effects of the Rose Windows in Mallorca Cathedral
Authors: Samper Albert , Moreno David , Herrera Blas
Published: March 2023

This research shows the light effects and geometric alignments created by the sunlight passing through the stained glasses of the Eastern rose window in Mallorca cathedral and projecting on the inner side of the cathedral’s main façade. Besides, we show other novel effects which occur in coincidence with certain religious festivities.
Smooth and Discrete Cone-Nets
Authors: Kilian Martin , Müller Christian , Tervooren Jonas
Published: March 2023

Cone-nets are conjugate nets on a surface such that along each individual curve of one family of parameter curves there is a cone in tangential contact with the surface. The corresponding conjugate curve network is projectively invariant and is characterized by the existence of particular transformations. We study properties of that transformation theory and illustrate how several known surface classes appear within our framework. We present cone-nets in the classical smooth setting of differential geometry as well as in the context of a consistent discretization with counterparts to all relevant statements and notions of the smooth setting. We direct special emphasis towards smooth and discrete tractrix surfaces which are characterized as principal cone-nets with constant geodesic curvature along one family of parameter curves.
The role of radiotherapy in the updated German S2k guideline for management of Merkel cell carcinoma
Authors: Vordermark Dirk , Höller Ulrike
Published: March 2023

Merkel cell carcinoma (MCC) is a radiosensitive tumor and the role of radiotherapy in the management of this disease was newly defined in the recently published update of the S2k guideline on Merkel cell carcinoma of the Association of Scientific Medical Societies in Germany (AWMF). While adjuvant radiotherapy of the tumor bed is broadly recommended, irradiation of the regional nodal region can be performed in patients with negative sentinel lymph nodes and high-risk factors. In patients with positive sentinel lymph nodes, it is an alternative to completion lymphadenectomy. The standard dose for adjuvant radiotherapy remains 50 Gy.
The Montecristo mining district, northern Chile: the relationship between vein-like magnetite-(apatite) and iron oxide-copper–gold deposits
Authors: Mateo Laura , Tornos Fernando , Hanchar John M. , Villa Igor M. , Stein Holly J. , Delgado Antonio
Published: March 2023

The Montecristo district, northern Chile, is one of the few places worldwide where there is a direct relationship between magnetite-(apatite) (MtAp) mineralization and iron oxide-copper–gold (IOCG) mineralization. The MtAp mineralization includes Ti-poor magnetite, fluorapatite, and actinolite and is crosscut and partially replaced by a younger IOCG mineralization that includes a second generation of actinolite and magnetite with quartz, chalcopyrite, pyrite, and molybdenite. The MtAp stage at Montecristo is interpreted as the crystallized iron-rich melts that used the pre-existing structures of the Atacama Fault System as conduits. These rocks later acted as a trap for hydrothermal IOCG mineralization. Geochronology data at Montecristo indicate that the host diorite (U–Pb zircon 153.3 ± 1.8 Ma, 2-sigma), MtAp mineralization (40Ar-39Ar in actinolite, 154 ± 2 Ma and 153 ± 4 Ma, 2-sigma), and the IOCG event (Re-Os on molybdenite, 151.8 ± 0.6 Ma, 2-sigma) are coeval within error and took place in a time span of less than 3.4 Ma. The εHfiand εNdivalues of the host diorite are + 8.0 to + 9.8 and + 4.3 to + 5.4, respectively. The whole-rock87Sr/86Srivalues of the IOCG mineralization (0.70425 to 0.70442) are in the lower end of those of the MtAp mineralization (0.70426–0.70629). In contrast, εNdivalues for the IOCG mineralization (+ 5.4 and + 5.7) fall between those of the MtAp rocks (+ 6.6 to + 7.2) and the host diorite, which suggests that the IOCG event was related to fluids having a more crustal Nd (εNdi <  + 5.7) composition than the MtAp mineralization. This likely reflects the mixing of Nd from the MtAp protolith and a deep magmatic-hydrothermal source, very likely an unexposed intrusion equivalent to the host diorite. Sulfur isotope compositions (δ34S, + 0.3 to + 3.4‰) are consistent with a magmatic source.
Normal reference values for magnetic resonance imaging measurements of the fetal internal jugular veins in middle and late pregnancy
Authors: Gao Duo , Liu Xin , Cao Yimin , Yi Zexi , Gao Xiaobin , Li Ying , Cao Cuili , Geng Zuojun , Zhou Lixia
Published: March 2023

Background

At present, there is a lack of normal magnetic resonance imaging (MRI) morphometric reference values for fetal internal jugular veins during middle and late pregnancy.

Objective

We used MRI to assess the morphology and cross-sectional area of the internal jugular veins of fetuses during middle and late pregnancy and to explore the clinical value of these parameters.

Materials and methods

The MRI images of 126 fetuses in middle and late pregnancy were retrospectively analysed to determine the optimal sequence for imaging the internal jugular veins. Morphological observation of the fetal internal jugular veins in each gestational week was carried out, lumen cross-sectional area was measured and the relationship between these data and gestational age was analysed.

Results

The balanced steady-state free precession sequence was superior to other MRI sequences used for fetal imaging. The cross section of fetal internal jugular veins was predominantly circular in both the middle and late stages of pregnancy, however the prevalence of an oval cross section was significantly higher in the late gestational age group. The cross-sectional area of the lumen of the fetal internal jugular veins increased with increasing gestational age. Fetal jugular vein asymmetry was common, with the right jugular vein being dominant in the high gestational age group.

Conclusion

We provide normal reference values for fetal internal jugular veins measured by MRI. These values may form the basis for clinical assessment of abnormal dilation or stenosis.