bluuebunny/crossref_metadata_2025 huggingface dataset:
Size Distributions and Health Risks of Particulate Polycyclic Aromatic Hydrocarbons in the Atmosphere at Coastal Areas in Ningbo, China
Authors: Wang Keqiang , Shi Yasheng , Zhang Jingjing , Tong Lei , Li Dan , Zheng Jie , Xiao Hang
Published: March 2024

Most current research focusing on the health risk assessments of particulate polycyclic aromatic hydrocarbons (PAHs) have not analyzed the size distributions and human respiratory deposition rates. In the present study, size-separated particulate matter (PM) was collected in the coastal area of Ningbo using an Anderson eight-stage air sampler over a 1-year period (2014–2015). The 16 US Environmental Protection Agency priority PAHs associated with PM were pretreated with rapid solvent extraction and analyzed by gas chromatography–mass spectrometry. The respiratory exposure assessment was determined using the multiple-path particle dosimetry (MPPD) model. The results show that all PAHs exhibited bimodal distribution with one mode peak in accumulation mode (0.43–0.65 µm) and another mode peak in coarse mode (4.7–5.8 µm). In addition, a low coefficient of divergence of PAHs between PM2.1 and PM2.1−10 indicated a high spatial heterogeneity in source factor contribution and formation mechanism. The deposition fluxes (tracheobronchial + pulmonary) of PM were highest for children in the size range of 3.3 µm < particle diameter (Dp) < 9 µm, while for males and females the highest fluxes occurred in the size range of 1.1 µm < Dp < 2.1 µm. The depositions of coarse PM in children were significantly higher than those in adults. The benzo[a]pyrene equivalent (BaPeq) depositions of dibenz[a,h]anthracene ranged from 1.4e-04 to 0.015 ng h−1, which were highest among the PAHs. The PAHs on particles with Dp >4.7 µm contributed approximately three times more to children than to males and females. Therefore, the toxicity of coarse PM to children needed attention. The incremental lifetime cancer risks (ILCR) for children, males, and females were estimated to be 2.92 × 10−7, 1.82 × 10−7, and 2.38 × 10−7, respectively, which were below the cancer risk guideline value (10−6). These ILCR values were much lower than the risks calculated without considering particle size distributions and respiratory depositions. The combination of the size-segregated sampling technique and the MPPD model can effectively avoid the overestimation of human respiratory exposure. Environ Toxicol Chem 2024;43:1364–1377. © 2024 SETAC
A mathematical‐boundary‐recognition domain‐decomposition Lattice Boltzmann method combined with large eddy simulation applied to airfoil aeroacoustics simulation
Authors: Jia Qi , Zhang Jin , Liang Wen‐zhi , Liu Pei‐qing , Qu Qiu‐lin
Published: March 2024

Being a direct computational aeroacoustics method, Lattice Boltzmann method (LBM) has great potential and broad application perspective in the field of numerical simulation of aerodynamic noise due to its low dispersion and low dissipation. A series of numerical algorithms and the related improvements based on the standard LBM method are proposed and developed in this paper to adapt to the airfoil noise calculation with complex grid at middle‐high Reynolds number. First, a new mathematical‐boundary‐recognition algorithm based on Green's formula is proposed to deal with complex curved geometric models, which is validated by three‐element airfoil 30P30N benchmark. Then, in order to reduce grid redundancy and improve computing efficiency, the grid refinement technique of domain decomposition model (DDM) is adopted and also improved, which is verified by calculating the flow and sound fields around 2D and 3D cylinders at Reynolds number equal to 90,000. Finally, three different LES turbulence models are combined with the standard MRT‐LBM method, where different finite difference schemes are used to solve Reynolds stress tensor which is different from the traditional one. Through the direct acoustic numerical simulation of NACA0012 airfoil at Reynolds number equal to 200,000, the effects of Smagorinsky models and Wall‐adapting local eddy‐viscosity (WALE) model on aerodynamic noise prediction are compared and analyzed. Overall, the proposed methodology is shown to be appropriate for predicting the aerodynamic noise at low Mach number and can successfully simulate the generation and propagation of far field acoustics.
Boosting Water Retention in Agriculture: Vine Biochar‐Doped Hydrogels' Swelling and Germination Effects
Authors: Uysal Yağmur , Doğaroğlu Zeynep Görkem , Makas Mehmet Nuri , Çaylali Zehranur
Published: March 2024

Water scarcity presents a formidable challenge to agriculture, particularly in arid, semiarid, and rainfed settings. In agricultural contexts, hydrogels serve as granular agents for water retention, undergoing considerable expansion upon water exposure. They assume versatile roles encompassing soil‐water retention, the dispensation of nutrients and pesticides, seed encapsulation, erosion mitigation, and even food supplementation. This study's objective involves the examination of biochar‐infused hydrogels, fashioned by incorporating vine pruning waste‐derived biochars, and the assessment of swelling behaviors in various aqueous environments encompassing deionized, tap, and saline water at concentrations of 0.5–1%. Characterizations of the vine‐biochars‐VB and biochar‐incorporated hydrogels‐VBHG are executed, with particular attention to their swelling properties across diverse media. As an initial step toward appraising their agricultural relevance, these hydrogels are introduced to a germination medium featuring wheat seeds to discern potential influences on germination dynamics. The maximum swelling capacity of VBHG is recorded in deionized water, tap water at pH 7.0, tap water at pH 9.0, saline water at 0.5%, and saline water at 1%, reaching 352%, 207%, 230%, 522%, and 549%, respectively. Remarkably, the 0.5% VBHG treatment exhibits the most pronounced root elongation. The application of hydrogels in agriculture exhibits promise, particularly within drought‐related contexts and potential soilless applications.
Examining the classification performance of pre‐trained capsule networks on imbalanced bone marrow cell dataset
Authors: Aydin Atasoy Nesrin , Faris Abdulla Al Rahhawi Amina
Published: March 2024

The automatic detection of bone marrow (BM) cell diseases plays a vital role in the medical field; it helps to make diagnoses more precise and effective, which leads to early detection and can significantly improve patient outcomes and increase the chances of successful intervention. This study proposed a fully automated intelligent system for BM classification by developing and enhancing Capsule Neural Network (CapsNet) architecture. Although CapsNet has demonstrated success in many classification tasks, it still has some limitations and challenges associated with using Convolutional Neural Networks (CNNs), which suffer from information loss during the pooling and discarding of detailed spatial information, resulting in the loss of fine‐grained features. Additionally, CNNs must help capture hierarchical feature relationships and often learn them implicitly by stacking convolutional layers. In contrast, CapsNets are designed to capture hierarchical features through dynamic routing and relationships between capsules, resulting in a more explicit representation of spatial hierarchy. CapsNets manage transformations and offer equivariance, preserving spatial information through capsule routing mechanisms. Further, to improve how features are represented, pre‐trained models such as Residual Capsule Network (RES‐CapsNet), Visual Geometry Group Capsule Network (VGG‐CapsNet), and Google Network (Inception V3) (GN‐CapsNet) have been used. This helps the network obtain the low‐ and mid‐level features and information it has previously learned so that subsequent capsule layers receive better initial information. Additionally, the Synthetic Minority Over‐Sampling Technique (SMOTE) was implemented to mitigate class imbalance. It generates synthetic samples in feature space by over‐sampling the minority class, leading to improving model performance in accurately classifying rare instances. Fine‐tuning the hyperparameters and implementing these improvements resulted in remarkable accuracy rates on a large BM dataset, with reduced training time and trainable parameters. CapsNet achieved 96.99%, VGG‐CapsNet achieved 98.95%, RES‐CapsNet achieved 99.24%, and the GN‐CapsNet model demonstrated superior accuracy at 99.45%. GN‐Caps Net was the best because it requires a small number of epochs and has an effective deep inception architecture that efficiently extracts features at different scales to form a robust representation of the input. Our proposed models were compared with existing state‐of‐the‐art models using the BM dataset; the results showed that our models outperformed the existing approaches and demonstrated excellent performance. Further, this automated system can analyze large amounts of data and complex cells in images of the BM dataset. Thus, it gives healthcare professionals a detailed understanding of different diseases, which may take time to achieve manually.
Efficiency and productivity growth in US food manufacturing industries: Exporters, ownership changes, and firm characteristics
Authors: Geylani Pinar Celikkol
Published: March 2024

This study employs a stochastic production frontier framework to measure productivity growth among exporters, non‐exporters, and firms experiencing ownership changes through mergers and acquisitions in US food manufacturing. Analyzing a panel data set that integrates Economic Censuses and transaction‐level exports, the results reveal the coexistence of more productive exporters, driven by technical efficiency, alongside less productive non‐exporters. Exporters in arm's length transactions show productivity growth driven by technical efficiency change, while those in related party transactions benefit mainly from technological change. Firms undergoing ownership changes exhibit positive productivity growth with a greater contribution from technical efficiency compared to those without such changes.
Challenges in the diagnosis and management of Robert's uterus: Systematic review and case presentation
Authors: Gulino Ferdinando Antonio , Occhipinti Sara , Ettore Carla , Incognito Giosuè Giordano , Russo Emanuele , Cannone Francesco Giuseppe , Ettore Giuseppe
Published: March 2024

Robert's uterus is a rare Müllerian duct anomaly (MDA) characterized by complete asymmetric septum dividing uterine cavity into two non‐communicating parts. This study offers insights into diagnosing and management of this condition in a young patient, and a systematic literature review. The review included 19 studies from 2013 to 2023. 11.4% of women reported a history of miscarriage and 5.7% primary infertility. Dysmenorrhea was the most frequent symptom (54.3%), and 14.3% of patients had a coexisting endometriosis. The surgical interventions most commonly combine laparoscopic and hysteroscopic techniques. Robert's uterus requires heightened clinical awareness for early diagnosis, particularly in young women.
The effect of augmented reality book on the proficiency of local anesthesia administration of the inferior alveolar nerve
Authors: Yari Amir , Fasih Paniz , Goodarzi Ali , Nouralishahi Atieh , Nikeghbal Dorsa
Published: March 2024

Background/objective

Advancements in augmented reality (AR) technology enable developers to create augmented reality books (AR Books). AR Books can show interactive 3D objects and multimedia content to the user. The purpose of this study was to investigate the effect of a developed AR Book on the theoretical and practical abilities in the administration of local anesthesia of the inferior alveolar nerve block.

Methods

An exclusive AR Book was developed based on Chapter 14, Handbook of Local Anesthesia, seventh edition, Stanley F. Malamed, which enabled students to use their book (printed or electronic) as an AR Book. Forty dental students were randomly divided into control and study groups. In the control group, students were asked to use regular books, while in the study group, students were instructed to use interactive AR Books. All students took the written exam, scoring 0 to 10. Also, the administration of mandibular local anesthesia was evaluated in students. The level of concentration during the study, the written exam score, the practical score, the success rate of local anesthesia, and the needed time for injection were compared between the two groups.

Results

There was a significant difference in the level of concentration during the study (p < 0.001), practical skill score (p = 0.037), and needed time for injection (p = 0.040) between the two groups. Conversely, the success rate of local anesthesia was almost similar (p = 0.705). Although the written exam score was higher in the study group than in the control group, the difference was not significant (p = 0.414).

Conclusion

Using AR Books can engage students and help them to remain focused during the study. AR Books may be beneficial in enhancing the practical abilities of dental students.
Acute effects of negative heel shoes on perceived pain and knee biomechanical characteristics of runners with patellofemoral pain
Authors: Gu Yu , Zheng Zhiyi , Zeng Quanshou , Yang Chen , Song Yu , Wan Xianglin
Published: March 2024

Background

To determine the effects of negative heel shoes on perceived pain and knee biomechanical characteristics of runners with patellofemoral pain (PFP) during running.

Methods

Sixteen runners with PFP ran in negative (−11 mm drops) and positive (5 mm drops) heel shoes while visual analog scale (VAS) scores, retroreflective markers, and ground reaction force were acquired by applying a 10‐cm VAS, infrared motion capture system, and a three‐dimensional force plate. Knee moment, patellofemoral joint stress (PFJS), and other biomechanical parameters during the stance phase were calculated based on inverse dynamics and a biomechanical model of the patellofemoral joint.

Results

The foot inclination angle, peak PFJS during the stance phase, patellofemoral joint reaction force, knee extension moment, and quadriceps force at the time of peak PFJS of runners with PFP in negative heel shoes were lower than that in positive heel shoes, no significant difference was found in VAS scores, knee flexion angle, patellofemoral contact area, and quadriceps moment arm at the time of peak PFJS.

Conclusions

Compared to positive heel shoes, running in negative heel shoes decreases peak PFJS in runners with PFP, which may decrease patellofemoral joint loading, thus reducing the possibility of further development of PFP.

Trail Registration

Sports Science Experiment Ethics Committee of Beijing Sport University. 2023095H, April 18, 2023 (prospectively registered).
It is Monday again: Weekend sleep differentially relates to the workweek via reattachment on Monday
Authors: Völker Jette , Wiegelmann Monika , Koch Theresa J. S. , Sonnentag Sabine
Published: March 2024

The weekend constitutes an important recovery period for employees. However, psychologically reattaching to work on Monday can be difficult because employees must transition from their private to their work role. Building on boundary theory and integrating a sleep and circadian perspective, we shed light on this transition by investigating antecedents and outcomes of Monday reattachment. We propose that three weekend sleep characteristics differentially relate to reattachment on Monday: weekend sleep quality, catch‐up sleep (extended sleep duration on the weekend), and social sleep lag (differences in sleep times workweek vs. weekend). Successful reattachment on Monday should, in turn, be related to lower levels of exhaustion and higher task performance during the workweek. We conducted a weekly diary study with 310 employees (933 weeks) over four workweeks. Two‐level path models demonstrated that higher weekend sleep quality was indirectly related to lower levels of workweek exhaustion via higher levels of Monday reattachment. In contrast, higher catch‐up sleep was related to higher levels of workweek exhaustion via lower levels of Monday reattachment. Accordingly, we demonstrate that Monday reattachment can set the tone for the entire workweek, but the capability to reattach can depend on weekend sleep as a core recovery process.
Development and perception of surgery‐specific goals of care discussions in the preoperative setting: A learning pilot
Authors: Letica‐Kriegel Allison S. , Rosen Roni , McNeil Nita , Thompson Errika , James Monique , Broach Vance , Roche Kara Long , Riportella Michaela , Ng Susan , Bernal Camila , Vaynrub Max , Downey Robert , Voigt Louis , Epstein Andrew S. , Nelson Judith , Goldfrank Deborah , Nash Garrett M.
Published: March 2024

Background

Goals of care discussions are infrequently documented in the preoperative period. Furthermore, documentation does not consistently address what matters most to patients, although patient values (PV) are central to person‐centered care.

Methods

A multidisciplinary working group was formed. An electronic note comprised of (1) topics of discussion, (2) PV, and (3) advance care planning (ACP), was created and embedded into existing note templates for Gynecologic Surgical Oncology. Surgeons and advanced practice providers (APPs) were educated to conduct and document these conversations in preoperative clinic for patients undergoing cancer surgery for a pilot period. Data were collected regarding usage of the template. Focus groups with surgeons, APPs, and patients were conducted. Qualitative analysis was performed on transcripts.

Results

During the pilot, 7 surgeon/APP teams utilized the template on a total of 55 notes. Average number of notes completed per surgeon was 7.8 (SD 8.5). Forty‐six notes (84%) included topics of discussion, 15 (27%) included PV, 4 (7%) included ACP. Qualitative analysis of focus group transcripts revealed that clinicians and patients perceived the initiative to be useful and important, although implementation barriers were identified.

Conclusion

Creating a surgery‐specific GOC template is feasible. Iterative revisions are needed to increase utility in clinic workflows.
Bilateral communication in procurement auctions
Authors: Brosig‐Koch Jeannette , Heinrich Timo , Sterner Martin
Published: March 2024

We ask how buyers can make use of bilateral communication in a procurement setting with moral hazard. We focus on a setting where buyers and potential sellers can exchange cheap‐talk messages before trading and where the seller is determined via a buyer‐determined procurement auction. In this type of auction, buyers can freely choose among bidders based on bidders' observable characteristics and the prices they ask for. In a controlled laboratory experiment, we found that buyers use free‐form text messages to make requests and to reduce social distance. The relationship between the offers sellers make and the messages they send is mediated by buyers' requests. But, in general, buyers may increase their profits by choosing sellers who promise high quality or large profits. Furthermore, despite the cheap‐talk nature of requests, buyers in our experiment increase their profits by specifically demanding high quality or large profits.
Examining the role of artificial intelligence in advancing pollution reduction strategies
Authors: Liu Fang , Liang Chen
Published: March 2024

This study is based on the panel data from 2006 to 2020 to explore the relationship between artificial intelligence (AI) and pollution emission. The study demonstrates a notable and statistically significant reduction in pollution emission intensity attributable to AI. This finding is robust, holding up under various sensitivity analyses and addressing endogeneity using instrumental variable techniques. The mechanism analysis reveals that AI's role in decreasing emissions primarily arises from three factors: the promotion of technological innovation, increased investment in emission reduction technology, and the replacement of low‐skilled labor with more efficient alternatives. We also find more substantial environmental benefits in areas with stricter environmental regulations and higher initial levels of pollution. Additionally, AI is shown to facilitate a symbiotic relationship between economic growth and environmental management. This research provides both empirical evidence and theoretical insights that reinforce the essential role of AI in driving green transformations, process upgrades, and high‐quality development. It situates these advancements within the broader context of the interplay between artificial intelligence, environmental sustainability, and economic progression.
Merger and acquisition, firm‐level cybersecurity risk, and research and development intensity
Authors: Vu Giang Thi Minh , Hoang Khanh , Hoang Huy Viet
Published: March 2024

This paper investigates the relationship between firm‐level cybersecurity risk and merger and acquisition (M&A) activities of firms in the United States from 2007 to 2018. Using a novel measure of firm‐level cybersecurity risk and the multivariate regression analysis, we find empirical evidence of a positive association between M&A and cybersecurity risk. Interestingly, cybersecurity risk only increases with intangible assets acquisitions, but not with tangible assets acquisitions. Further empirical analysis shows that the impact of M&A on cybersecurity risk is moderated by technological intensity, with firms that have higher levels of research and development (R&D) intensity facing less pronounced cybersecurity risk. Our findings are robust to different variable measurements and endogeneity diagnoses. Our results deliver important implications for practitioners and policymakers and make a valuable contribution to the literature by providing a more comprehensive understanding of the relationship between M&A and cybersecurity risk and by highlighting the role of corporate innovation in mitigating this risk.
Clinical effectiveness of postoperative prostaglandin E1 administration in reducing flap necrosis following microsurgical reconstruction
Authors: Park Se Yeon , Lee Kyeong‐Tae
Published: March 2024

Background

Extensive experimental evidence has suggested the potential efficacy of prostaglandin E1 (PGE1) in enhancing flap survival, leading to its widespread empirical use following free flap operation. However, the translation of these experimental findings into clinical benefits remains uncertain. This study aimed to assess the clinical effectiveness of postoperative PGE1 administration on the outcomes of microsurgical reconstruction.

Methods

A retrospective review was conducted for patients who underwent free flap‐based reconstruction between September 2020 and November 2022, dividing into two cohorts. For all consecutive cases conducted during the formal half, PGE1 was administered for postoperative 7 days (PGE1 cohort), and for those during the latter, PGE1 was not given (non‐PGE1 cohort). The profiles of perfusion‐related complications (PRC) were compared between the two cohorts. Further analyses after propensity‐score matching were performed.

Results

In total, 274 cases were analyzed, consisting of 142 in PGE1 and 132 in non‐PGE1 cohort. Baseline characteristics were similar between the two cohorts, except for higher rates of comorbidities and chronic wound‐related defects in the PGE1 cohort. Overall PRC developed in 37 cases (13.5%), including 6 (2.1%) total loss and 38 (10.2%) partial necrosis. Compared to the control, the PGE1 cohort exhibited significantly lower rates of overall PRC and partial flap necrosis. This difference remained significant on multivariable analyses. The rate of total flap loss did not differ between the cohorts. Consistent associations were observed in the propensity‐score matching analysis.

Conclusion

Postoperative administration of PGE1 appears to be associated with reduced risks for the development of partial flap necrosis.
Serial electrodiagnostic testing: Utility and indications in adult neurological disorders
Authors: Hearn Sandra L. , Stino Amro Maher , Howard Ileana M. , Malhotra Gautam , Robinson Lawrence
Published: March 2024

Although existing guidelines address electrodiagnostic (EDX) testing in identifying neuromuscular conditions, guidance regarding the uses and limitations of serial (or repeat) EDX testing is limited. By assessing neurophysiological change longitudinally across time, serial electrodiagnosis can clarify a diagnosis and potentially provide valuable prognostic information. This monograph presents four broad indications for serial electrodiagnosis in adult peripheral neurological disorders. First, where clinical change has raised suspicion for a new or ongoing lesion, EDX reassessment for spatial spread of abnormality, involvement of previously normal muscle or nerve, and/or evolving pathophysiology can clarify a diagnosis. Second, where diagnosis of a progressive neuromuscular condition is uncertain, electrophysiological data from a second time point can confirm or refute suspicion. Third, to establish prognosis after a static nerve injury, a repeat study can assess the presence and extent of reinnervation. Finally, faced with a limited initial study (as when complicated by patient or environmental factors), a repeat EDX study can supplement missing or limited data to provide needed clarity. Repeat EDX studies carry certain limitations, however, such as with prognostication in the setting of remote or chronic lesions, sensory predominant fascicular injury, or mild axonal injury. Nevertheless, serial electrodiagnosis remains a valuable and underused tool in the diagnostic and prognostic evaluation of neuromuscular conditions.
Speed‐Dating für die Chemie
Authors: Remenyi Christian
Published: March 2024

700 Partnering‐Gespräche, 250 Teilnehmer in Präsenz – das achte European Chemistry Partnering (ECP) startete nach den Corona‐Jahren neu durch.
Bilanz Merck 2023: Mehr Medikamente, weniger Elektronik
Authors: Bulmahn Maren
Published: March 2024

Beim Darmstädter Konzern Merck fehlten im Jahr 2023 die pandemiebedingten Umsätze mit Tests, Labormaterialien und Lipiden für Impfstoffe. Zudem verkauften sich Halbleitermaterialien und Flüssigkristalle schlecht.
Bilanz Novartis 2023: Fürs Herz und gegen Krebs
Authors: Bulmahn Maren
Published: March 2024

Das Pharmaunternehmen Novartis hat sich im Jahr 2023 von seinen Generika‐Aktivitäten getrennt. Der Umsatz wuchs insgesamt um zehn Prozent.
Ig‐Nobelpreis: Von Sinnen
Authors: Blicker Luca
Published: March 2024

Der Ig‐Nobelpreis im Jahr 2023 war ein visuelles, gustatorisches, haptisches und olfaktorisches Fest: Die Gewinner:innen der naturwissenschaftlichen Rubriken haben Steine abgeleckt, einen Spinnengreifarm entwickelt und eine Toilette mit Ausscheidungs‐Check gebaut.
Networking Platform: For transfer and collaboration
Authors: Abele Stefan
Published: March 2024

A forum for chemists, chemical and process engineers promotes the sustainable growth of the Swiss chemical industry. It aims to emphasize the importance of chemical production and process development in research, education, industry and politics. This portrait reveals how it does this.
Farben des Jahres: Prophetischer Pfirsichflaum ist wie eine sanfte Umarmung
Authors: Bulmahn Maren
Published: March 2024

Unternehmen empfehlen Farben, die zum Zustand der Welt passen und sich vor allem gut verkaufen lassen sollen. Bei Autos scheinen das wie immer die Nichtfarben Schwarz, Weiß und Grau zu sein. Eine Ausnahme bildet in diesem Jahr Schweinchenrosa. Welche Branchen weltweit mitmachen.
Pro & Contra Verpackungen: Im Unverpackt‐Laden 84 Prozent Verpackung einsparen
Authors: Holzmann Chrissi
Published: March 2024

Chrissi Holzmann findet: Die beste Verpackung ist die, die gar nicht erst entsteht.
Von CO2‐Abschneidern und F‐gedopten Athleten
Authors: Remenyi Christian
Published: March 2024

Manchmal ist es traurig, dass in der Welt da draußen so viele Menschen herumlaufen, die Chemie nach der 9. Klasse abgewählt haben. Aber oft entsteht dadurch auch irrsinnig Komisches.
„Blättern und Lesen im Garten“
Authors: Wille Eva E.
Published: March 2024

Eva E. Wille erhielt Mitte März auf der Chemiedozententagung die Gmelin‐Beilstein‐Denkmünze für ihr außergewöhnliches Engagement zur Etablierung und Weiterentwicklung der chemischen Literatur. Der Preis wird seit 1954 in geraden Jahren vergeben und umfasst neben einer Urkunde eine Silbermedaille und 7500 Euro Preisgeld.
Vorstandssitzung
Authors: Koch Wolfram
Published: March 2024

Ende der Amtsperiode: Bericht über die Sitzung des GDCh‐Vorstands am 5. Dezember 2023 in Weinheim.
Geschichte der Chemie neu denken
Authors: Jost Jürgen , Restrepo Guillermo
Published: March 2024

Neue Forschungsansätze zur Geschichte der Chemie präsentierte die Tagung Multidisciplinary approaches to the history of chemistry in Leipzig Ende Januar.
Effect of 1‐ethylpyridinium bromide on enhancing the dispersion of silica and interfacial strength in rubber‐silica composite
Authors: Sun Weixing , Liu Guixiang , Fan Xinpeng , Liao Shuangquan
Published: March 2024

Improving the interfacial interaction between silica and rubber is always a key issue to be solved for silica‐filled rubbers. In this paper, composites are prepared by an in‐situ modification method using 1‐ethylpyridinium bromide ([EPy]Br) as the raw material, and the effect of its dosage on the interfacial interactions and macroscopic properties of silica‐filled natural rubber (NR) composites is investigated. The effect of [EPy]Br on silica dispersion and interfacial interaction between silica and NR is verified through rheological tests and calculations of glass layers. Compared with the original samples, composite performance is optimized when the usage amount is at 1phr which increases tensile strength by 5 MPa, enhances abrasion resistance by 24%, and shortens optimum curing time in half. This study is expected to provide a new strategy for improving the processability of silica‐containing composites while reducing energy consumption.

Highlights

[EPy]Br enhances the interaction between rubber and filler while modifying the surface of silica.

Increasing the dosage of [EPy]Br leads to a reduction in the Payne effect.

The addition of [EPy]Br enhances the dispersion of silica in natural rubber.

[EPy]Br significantly reduces the duration of the induction period for vulcanization.

The dosage of [EPy]Br allows for controlling the mechanical properties of NR/SiO2.
Preload relaxation behavior and its influence on the mechanical performance of bolted carbon fiber‐reinforced thermoplastic sheet molding compound joints
Authors: Tong X. , Meng L. , Wan Y. , Takahashi J.
Published: March 2024

In this study, the relaxation of the initial tightening preload of bolted carbon fiber reinforced thermoplastic sheet molding compound (CFRTP‐SMC) joints was experimentally investigated under different temperatures and initial preload conditions. The influence of preload relaxation on the bolted structures was evaluated using static bearing tests, whereas the failure modes during the test were verified based on metallographic observations. The experimental results indicate that the speed of the preload relaxation can be accelerated by increasing the temperature and initial preload. The static bearing strength of the bolted SMC material decreased with a continuous increase in the preload loss. Furthermore, the existence of a lateral preload protected the material around the assembly hole from buckling, resulting in a higher static bearing strength. The shielding effect of the preload was weakened after the relaxation of the initial preload.

Highlights

Elevated temperature and initial preload can expedite the relaxation process.

Preload loss will result in a declined static bearing performance.

Initial tightening preload can protect the bolted SMC material from buckling.
Bending characteristics of partially reinforced aluminum/CFRP hybrid hat‐section beam structures with an adhesively bonded joint: An experimental, numerical, and analytical study
Authors: Hampaiyan Miandowab Hamed , Rahmani Reza , Saeidi Googarchin Hamad
Published: March 2024

A significant feature about hybrid structures is the strengthening of critical areas in order to increase the load capacity of the beams. This research evaluates the energy absorption capability and bending collapse behavior of an aluminum hat‐section with adhesively bonded of carbon fiber reinforced plastic (CFRP) as a partial reinforcement (PR) hybrid beam. The aluminum layers and processed CFRP laminates were bonded with adhesive joints to produce the beams with varied layups for hybrid beams. The specimens showed a range of bending collapses, and the hybrid specimens' peak load and load drop differed depending on failure mechanism. The experimental results reveal that the amount of SEA of the hybrid beam specimens was higher compared with that of the aluminum beam, with Al/CFRP [0/90]S PR hybrid beam exhibiting an 85.9% improvement in SEA value. Subsequently, FE models of aluminum and hybrid beams were developed for bending collapse analysis, and the finite element results were consistent with the experimental specimens' validation. In addition, the consequences of progressive damage failure in the interface effect and transverse matrix damage in various layups were investigated. Eventually, the Kecman model is used to perform analytical modeling of hybrid and aluminum beams in order to examine the impact of CFRP partial reinforcing components based on various bending moment hinge lines.

Highlight

Bending characteristics of adhesively bonded partially reinforced Al/CFRP beam

Experimental and numerical investigation on the beams under three‐point bending

Analytical study for the prediction of energy absorption characteristics

A good agreement between numerical, theoretical and experimental results
Comprehensive profiling of the human fecal proteome from IBD patients with DIA‐MS enables evaluation of disease‐relevant proteins
Authors: Harder Brandon J. , Lekkerkerker Annemarie N. , Casavant Ellen P. , Hackney Jason A. , Nguyen Allen , McBride Jacqueline M. , Mathews William Rodney , Anania Veronica G.
Published: March 2024

Purpose

Inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn's disease (CD), is characterized by chronic gastrointestinal inflammation. A high unmet need exists for noninvasive biomarkers in IBD to monitor changes in disease activity and guide treatment decisions. Stool is an easily accessed, disease proximal matrix in IBD, however the composition of the IBD fecal proteome remains poorly characterized.

Experimental Design

A data‐independent acquisition LC‐MS/MS approach was used to profile the human fecal proteome in two independent cohorts (Cohort 1: healthy n = 5, UC n = 5, CD n = 5, Cohort 2: healthy n = 20, UC n = 10, and CD n = 10) to identify noninvasive biomarkers reflective of disease activity.

Results

688 human proteins were quantified, with 523 measured in both cohorts. In UC stool 96 proteins were differentially abundant and in CD stool 126 proteins were differentially abundant compared to healthy stool (absolute log2 fold change > 1, p‐value < 0.05). Many of these fecal proteins are associated with infiltrating immune cells and ulceration/rectal bleeding, which are hallmarks of IBD pathobiology. Mapping the identified fecal proteins to a whole blood single‐cell RNA sequencing data set revealed the involvement of various immune cell subsets to the IBD fecal proteome.

Conclusions and Clinical Relevance

Findings from this study not only confirmed the presence of established fecal biomarkers for IBD, such as calprotectin and lactoferrin, but also revealed new fecal proteins from multiple pathways known to be dysregulated in IBD. These novel proteins could serve as potential noninvasive biomarkers to monitor specific aspects of IBD disease activity which could expedite clinical development of novel therapeutic targets.
Association between cytomegalovirus infection and neurological disorders: A systematic review
Authors: Sanami Samira , Shamsabadi Shahnam , Dayhimi Amir , Pirhayati Mohammad , Ahmad Sajjad , Pirhayati Ahmadreza , Ajami Marjan , Hemati Sara , Shirvani Masoud , Alagha Ahmad , Abbarin Davood , Alizadeh Akram , Pazoki‐Toroudi Hamidreza
Published: March 2024

Cytomegalovirus (CMV) belongs to the Herpesviridae family and is also known as human herpesvirus type 5. It is a common virus that usually doesn't cause any symptoms in healthy individuals. However, once infected, the virus remains in the host's body for life and can reactivate when the host's immune system weakens. This virus has been linked to several neurological disorders, including Alzheimer's disease, Parkinson's disease, Autism spectrum disorder, Huntington's disease (HD), ataxia, Bell's palsy (BP), and brain tumours, which can cause a wide range of symptoms and challenges for those affected. CMV may influence inflammation, contribute to brain tissue damage, and elevate the risk of moderate‐to‐severe dementia. Multiple studies suggest a potential association between CMV and ataxia in various conditions, including Guillain‐Barré syndrome, chronic inflammatory demyelinating polyneuropathy, acute cerebellitis, etc. On the other hand, the evidence regarding CMV involvement in BP is conflicting, and also early indications of a link between CMV and HD were challenged by subsequent research disproving CMV's presence. This systematic review aims to comprehensively investigate any link between the pathogenesis of CMV and its potential role in neurological disorders and follows the preferred reporting items for systematic review and meta‐analysis checklist. Despite significant research into the potential links between CMV infection and various neurological disorders, the direct cause‐effect relationship is not fully understood and several gaps in knowledge persist. Therefore, continued research is necessary to gain a better understanding of the role of CMV in neurological disorders and potential treatment avenues.
A compact RTK‐GNSS device for high‐precision localization of outdoor mobile robots
Authors: Lee Sung‐Jin , Kim Bit , Yang Dong‐Wook , Kim Junseo , Parkinson Tom , Billingham Johsan , Park Chulwoo , Yoon Jinsung , Lee Dae‐Young
Published: March 2024

Accurate location information is crucial for ensuring the reliability of service robots, such as field vehicles and agricultural robots. These practical robots often encounter fluctuating or inclined terrains in dynamic conditions during operation. Additionally, the performance of mobile robots depends on the physical size and weight of the localization system–physically heavy systems may degrade performance. In this paper, we present a compact, lightweight RTK‐GNSS device weighing under 40 g, which achieves centimeter‐level accuracy across different attitudes and dynamic situations. To enhance signal reception and positioning performance, we lessen noise levels in the power circuit and radio‐frequency signal conditioning using a low‐dropout regulator and low‐noise amplifier. Utilizing the configured device, we verified centimeter‐level accuracy through experiments of tracking an unmanned ground vehicle. The potential of the device is substantiated via three application scenarios—a localization of a moving human for a wearable device, a heading estimation of a mobile robot in stationary conditions, and practical field tests in various signal‐reception environments. Attributable to its compact dimensions and lightweight features, the proposed device can yield a low system strain while maintaining high accuracy and reliable performance, rendering it highly adaptable for various robotic applications.
Review on research and development of planetary penetrator
Authors: Zhou Jianqin , Feng Jingkai , Liu Jinguo , Xu Cheng , Tian Yuanzheng , Lu Da
Published: March 2024

A planetary penetrator is a kind of machine that can use its special structure to independently penetrate an exoplanet and sample it for storage. It is a hot research topic in the world and has important development potential in the field of deep space exploration. Based on the analysis of relevant literature, this paper classifies and compares various representative planetary penetrator projectiles around the current research status. The development progress and key technologies of the planetary penetrator are analyzed, the current technical challenges are summarized, and the development trend of the planetary penetrator has prospected. The planetary probe has a broad application prospect, and its development will provide technical support for humans to establish extraterrestrial habitat, and play an important role in the field of deep space exploration. Currently, planetary penetrator research is still in its infancy, and the field is full of possibilities that need to be explored and improved.
The hitting time of clique factors
Authors: Heckel Annika , Kaufmann Marc , Müller Noela , Pasch Matija
Published: March 2024

In [Trans. Am. Math. Soc. 375 (2022), no. 1, 627–668], Kahn gave the strongest possible, affirmative, answer to Shamir's problem, which had been open since the late 1970s: Let and let be divisible by . Then, in the random ‐uniform hypergraph process on vertices, as soon as the last isolated vertex disappears, a perfect matching emerges. In the present work, we prove the analogue of this result for clique factors in the random graph process: at the time that the last vertex joins a copy of the complete graph , the random graph process contains a ‐factor. Our proof draws on a novel sequence of couplings which embeds the random hypergraph process into the cliques of the random graph process. An analogous result is proved for clique factors in the ‐uniform hypergraph process ().
Phytin recovered from grain distillation can serve as a phosphorus fertilizer for maize and soybean
Authors: Lee Jeonggu , Hertzberger Allan , Juneja Ankita , Cusick Roland , Singh Vijay , Margenot Andrew J.
Published: March 2024

Phosphorus (P) recovery from waste streams can increase food system P use efficiency while simultaneousl mitigating point source P losses. Phytin is a P‐rich waste product generated from maize grain biorefineries, largely located in the US Midwest. However, since the majority of P in phytin is organic, phytin‐P is likely to have limited crop availability in soil following application, as it must first be mineralized to orthophosphate‐P by soil phosphatases. To evaluate the fertilizer potential of phytin recovered from a maize wet milling plant and test hypothesized mechanisms of P mineralization, a five‐step gradient of phytin substitution for monoammonium phosphate (MAP) (0%, 25%, 50%, 75%, and 100% substitution) was evaluated for maize (Zea mays L.) and soybean (Glycine max L.) growth in a P‐deficient Aquic Argiudoll. Irrespective of crop species, aboveground biomass at end of vegetative growth (VT stage) was similar for up to 75% phytin substitution as MAP, but was 21% lower for maize and 49% for soybean when phytin was fully substituted for MAP. Soil microbial biomass carbon (C), nitrogen (N), and P, as well as activities of phosphomonoesterase and phosphodiesterase were invariant across the phytin substitution gradient, suggesting negligible mineralization of phytin P. Full substitution of MAP with phytin lowered soil microbial biomass C:N by 121% for maize and by 153% for soybean, and soil phosphatase activities per unit microbial biomass C were 24% higher under soybean. Our results indicate that phytin can be partially substituted for highly water‐soluble P fertilizers for the two major crop species of the US Midwest in which phytin waste generation is co‐located.
Examining activity–pH relationships of soil nitrogen hydrolytic enzymes
Authors: Daughtridge Rachel C. , Margenot Andrew J.
Published: March 2024

Nitrogen (N) depolymerization and mineralization in soils are catalyzed by extracellular enzymes, notably proteolytic and chitinolytic enzymes. However, there is limited knowledge of pH optima of these N‐hydrolytic soil enzymes, potentially missing insights to soil pH effects on N cycling and requiring assumptions on pH optima in enzyme activity assays. We evaluated pH optima of five N‐hydrolytic enzymes (casein protease, leucine aminopeptidase, glycine aminopeptidase, alanine aminopeptidase, N‐acetyl‐β‐glucosaminidase) in soils under long‐term (145‐year) fertilization and crop rotation treatments, as well as a restored prairie, on an Aquic Argiudoll. We additionally tested the pH dependency of three types of non‐enzymatic interferences in order to assess the relative importance of controls in determining N‐hydrolytic enzyme activity pH optima. For all enzymes, pH–activity relationships varied by soil and exhibited secondary pH optima, though primary pH optima generally agreed with values reported for purified, non‐soil enzymes. Enzyme activity pH optima did not reflect soil pH, though soil pH ranged 6.2–7.4 across 145‐year treatments. Nonenzymatic interference was generally pH‐dependent and soil‐specific for protease and N‐acetyl‐β‐glucosaminidase. Though omitting controls for dissolved organic matter tended to have the largest effect on pH optima misestimation, controlling for all three sources of interference had appreciable effects on estimated pH optima values. This study provides a benchmark of empirically determined pH optima of multiple hydrolytic enzymes that catalyze soil N depolymerization. We demonstrate that soil N‐hydrolytic enzyme activities exhibit pH optima that generally vary most by enzyme type, and specifically between proteolytic versus chitinolytic enzymes. Because pH optima of these soil enzyme activities can vary among soils differing in management and land use, pH optima should be determined a priori.
In Situ Synthesis of CuxO/N Doped Graphdiyne with Pyridine N Configuration for Ammonia Production via Nitrate Reduction
Authors: Li Jian , Valenza Roberto , Haussener Sophia
Published: March 2024

Electroreduction of nitrate to ammonia provides an interesting pathway for wastewater treatment and valorization. Cu‐based catalysts are active for the conversion of NO3− to NO2− but suffer from an inefficient hydrogenation process of NO2−. Herein, CuxO/N‐doped graphdiyne (CuxO/N‐GDY) with pyridine N configuration are in situ prepared in one pot. Benefiting from the synergistic effect of pyridinic N in GDY and CuxO, the prepared CuxO/N‐GDY tested in a commercial H‐cell achieved a faradaic efficiency of 85% toward NH3 at ‐0.5 V versus RHE with a production rate of 340 µmol h−1 mgcat−1 in 0.1 M KNO3. When integrating the CuxO/N‐GDY in an anion exchange membrane flow electrolyzer, a maximum Faradaic efficiency of 89% is achieved at a voltage of 2.3 V and the production rate is 1680 µmol h−1 mgcat−1 at 3.3 V in 0.1 M KNO3 at room temperature. Operation at 40 °C further promoted the overall reaction kinetics of NO3− to NH3, but penalized its selectivity with respect to hydrogen evolution reaction. The high selectivity and production rate in this device configuration demonstrate its potential for industrial application.
Hollow Cu2‐xS@NiFe Layered Double Hydroxide Core–Shell S‐Scheme Heterojunctions with Broad‐Spectrum Response and Enhanced Photothermal‐Photocatalytic Performance
Authors: Zhang Na , Wang Yichao , Liu Meijie , Cheng Tao , Xing Zipeng , Li Zhenzi , Zhou Wei
Published: March 2024

Designing a reasonable heterojunction is an efficient path to improve the separation of photogenerated charges and enhance photocatalytic activity. In this study, Cu2‐xS@NiFe‐LDH hollow nanoboxes with core–shell structure are successfully prepared. The results show that Cu2‐xS@NiFe‐LDH with broad‐spectrum response has good photothermal and photocatalytic activity, and the photocatalytic activity and stability of the catalyst are enhanced by the establishment of unique hollow structure and core–shell heterojunction structure. Transient PL spectra (TRPL) indicates that constructing Cu2‐xS@NiFe‐LDH heterojunction can prolong carrier lifetime obviously. Cu2‐xS@NiFe‐LDH shows a high photocatalytic hydrogen production efficiency (5176.93 µmol h−1 g−1), and tetracycline degradation efficiency (98.3%), and its hydrogen production rate is ≈10–12 times that of pure Cu2‐xS and NiFe‐LDH. In situ X‐ray photoelectron spectroscopy (XPS) and electron spin resonance (ESR) provide proofs of the S‐scheme electron transfer path. The S‐scheme heterojunction achieves high spatial charge separation and exhibits strong photoredox ability, thus improving the photocatalytic performance.