bluuebunny/crossref_metadata_2025 huggingface dataset:
Improved Cell Adhesion on Self‐Assembled Chiral Nematic Cellulose Nanocrystal Films
Authors: Wang Xiaoxiao , Xu Haifeng , Ning Fanghui , Duan Shun , Hu Yang , Ding Xiaokang , Xu Fu‐Jian
Published: June 2024

Chirality is ubiquitous in nature, and closely related to biological phenomena. Nature‐originated nanomaterials such as cellulose nanocrystals (CNCs) are able to self‐assemble into hierarchical chiral nematic CNC films and impart handedness to nano and micro scale. However, the effects of the chiral nematic surfaces on cell adhesion are still unknown. Herein, this work presents evidence that the left‐handed self‐assembled chiral nematic CNC films (L‐CNC) significantly improve the adhesion of L929 fibroblasts compared to randomly arranged isotropic CNC films (I‐CNC). The fluidic force microscopy‐based single‐cell force spectroscopy is introduced to assess the cell adhesion forces on the substrates of L‐CNC and I‐CNC, respectively. With this method, a maximum adhesion force of 133.2 nN is quantified for mature L929 fibroblasts after culturing for 24 h on L‐CNC, whereas the L929 fibroblasts exert a maximum adhesion force of 78.4 nN on I‐CNC under the same condition. Moreover, the instant SCFS reveals that the integrin pathways are involved in sensing the chirality of substrate surfaces. Overall, this work offers a starting point for the regulation of cell adhesion via the self‐assembled nano and micro architecture of chiral nematic CNC films, with potential practical applications in tissue engineering and regenerative medicine.
AKAP95 regulates ubiquitination and degradation of cyclin Ds/Es, influencing the G1/S transition of lung cancer cells
Authors: Deng Zifeng , Dou Liangding , Luo Zhen , Liu Rong , Zhang Jinwen , Wang Jing , Wang Dai , Guo DongBei , An Ran , Yao Youliang , Qiu Guihua , Zhang Yongxing
Published: June 2024

A‐kinase anchoring protein 95 (AKAP95) functions as a scaffold for protein kinase A. Prior work by our group has shown that AKAP95, in coordination with Connexin 43 (Cx43), modulates the expression of cyclin D and E proteins, thus affecting the cell cycle progression in lung cancer cells. In the current study, we confirmed that AKAP95 forms a complex with Cx43. Moreover, it associates with cyclins D1 and E1 during the G1 phase, leading to the formation of protein complexes that subsequently translocate to the nucleus. These findings indicate that AKAP95 might facilitate the nuclear transport of cyclins D1 and E1. Throughout this process, AKAP95 and Cx43 collectively regulate the expression of cyclin D, phosphorylate cyclin E1 proteins, and target their specific ubiquitin ligases, ultimately impacting cell cycle progression.
Investigation of Changes in the Polyphenol Profile Verified by LC‐MS/MS and the Pro‐Health Activities of Fruit Smoothie
Authors: Borowiec Kamila , Szwajgier Dominik , Stachniuk Anna , Mielniczuk Jacek , Trzpil Alicja
Published: June 2024

Scope

Bilberry, bananas, and apples are used for smoothie production because the health‐promoting activities and to prevent human diseases including neurodegenerative disorders. The smoothie is prepared to promote a promising practice for increasing the intake of fruit in the diet.

Methods and results

The smoothie is packed into dark glass jars, pasteurized, and stored for up to 4 months at 4 or 22 °C. Then, it is analyzed for the polyphenols profile using liquid chromatography‐high resolution mass spectometry (LC‐HRMS) Polyphenols content and the antiinflammatory, anticholinesterase, and antioxidant activities, and the impact on catalase activity are controlled using biochemical analyses. A significant decrease in the flavanol content (p < 0.05) is investigated, while there are lower decreases or no changes in the other polyphenols content in the smoothies stored at 4 °C. The changes in the anticholinesterase and antioxidant activities of the smoothie are correlated with the total polyphenols, anthocyanins, flavonols, and tannins content.

Conclusion

The proposed preservation of the smoothie and its storage at refrigeration temperature is adequate to maintain the smoothie's nutritional and functional effect for a 4‐month shelf life. Even significant changes in the content of individual subgroups of polyphenols are not drastically reflected in the decrease of the smoothie biological activities.
Identifying radiogenomic associations of breast cancer based on DCE‐MRI by using Siamese Neural Network with manufacturer bias normalization
Authors: Chen Junhua , Zeng Haiyan , Cheng Yanyan , Yang Banghua
Published: June 2024

Background and Purpose

The immunohistochemical test (IHC) for Human Epidermal Growth Factor Receptor 2 (HER2) and hormone receptors (HR) provides prognostic information and guides treatment for patients with invasive breast cancer. The objective of this paper is to establish a non‐invasive system for identifying HER2 and HR in breast cancer using dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI).

Methods

In light of the absence of high‐performance algorithms and external validation in previously published methods, this study utilizes 3D deep features and radiomics features to represent the information of the Region of Interest (ROI). A Siamese Neural Network was employed as the classifier, with 3D deep features and radiomics features serving as the network input. To neutralize manufacturer bias, a batch effect normalization method, ComBat, was introduced. To enhance the reliability of the study, two datasets, Predict Your Therapeutic Response with Imaging and moLecular Analysis (I‐SPY 1) and I‐SPY 2, were incorporated. I‐SPY 2 was utilized for model training and validation, while I‐SPY 1 was exclusively employed for external validation. Additionally, a breast tumor segmentation network was trained to improve radiomic feature extraction.

Results

The results indicate that our approach achieved an average Area Under the Curve (AUC) of 0.632, with a Standard Error of the Mean (SEM) of 0.042 for HER2 prediction in the I‐SPY 2 dataset. For HR prediction, our method attained an AUC of 0.635 (SEM 0.041), surpassing other published methods in the AUC metric. Moreover, the proposed method yielded competitive results in other metrics. In external validation using the I‐SPY 1 dataset, our approach achieved an AUC of 0.567 (SEM 0.032) for HR prediction and 0.563 (SEM 0.033) for HER2 prediction.

Conclusion

This study proposes a non‐invasive system for identifying HER2 and HR in breast cancer. Although the results do not conclusively demonstrate superiority in both tasks, they indicate that the proposed method achieved good performance and is a competitive classifier compared to other reference methods. Ablation studies demonstrate that both radiomics features and deep features for the Siamese Neural Network are beneficial for the model. The introduced manufacturer bias normalization method has been shown to enhance the method's performance. Furthermore, the external validation of the method enhances the reliability of this research. Source code, pre‐trained segmentation network, Radiomics and deep features, data for statistical analysis, and Supporting Information of this article are online at: https://github.com/FORRESTHUACHEN/Siamese_Neural_Network_based_Brest_cancer_Radiogenomic.
Reducing blood flow pulsation artifacts in 3D time‐of‐flight angiography by locally scrambling the order of the acquisition at 3 T and 7 T
Authors: Seginer Amir , Niry Dana , Furman‐Haran Edna , Kolb Hadar , Schmidt Rita
Published: June 2024

Purpose

Non‐contrast‐enhanced time of flight (TOF) is a standard method for magnetic resonance angiography used to depict vessel morphology. TOF is commonly performed with a 3D steady‐state acquisition, employing a short repetition time to support high resolution imaging. At 7 T, TOF exhibits substantial increase in SNR and contrast, improving its clinical value. However, one of the remaining challenges, exacerbated at 7 T, is the presence of artifacts due to pulsatile blood flow, especially near major blood vessels. In this study we examine a method to significantly reduce these artifacts.

Methods

We recently introduced a new “local‐scrambling” approach that semi‐randomizes the acquisition order of the phase encodes, to achieve a controllable cutoff frequency above which the artifacts are drastically reduced. With this approach, artifacts resulting from fast local fluctuations such as cardiac pulsation are significantly reduced. In this study, we explore the ability of this local‐scrambling approach to reduce pulsatile blood flow artifacts in a 3D TOF acquisition. Cartesian line‐by‐line and center‐out ordering, with and without local‐scrambling, were compared in simulations and in human brain imaging at 3 and 7 T scanners.

Results

In the simulations the artifact intensity showed a 10‐fold reduction using local‐scrambling compared to line‐by‐line and 4‐fold compared to center‐out ordering. In vivo results show that artifacts are much more pronounced at 7 T compared to 3 T, and in both cases they are effectively reduced by local‐scrambling.

Conclusion

Local‐scrambling improves image quality for both line‐by‐line and center‐out ordering. This approach can easily be implemented in the scanner without any changes to the reconstruction.
Accelerated 3D metabolite T1 mapping of the brain using variable‐flip‐angle SPICE
Authors: Zhao Yibo , Li Yudu , Guo Rong , Jin Wen , Sutton Brad , Ma Chao , El Fakhri Georges , Li Yao , Luo Jie , Liang Zhi‐Pei
Published: June 2024

Purpose

To develop a practical method to enable 3D T1 mapping of brain metabolites.

Theory and Methods

Due to the high dimensionality of the imaging problem underlying metabolite T1 mapping, measurement of metabolite T1 values has been currently limited to a single voxel or slice. This work achieved 3D metabolite T1 mapping by leveraging a recent ultrafast MRSI technique called SPICE (spectroscopic imaging by exploiting spatiospectral correlation). The Ernst‐angle FID MRSI data acquisition used in SPICE was extended to variable flip angles, with variable‐density sparse sampling for efficient encoding of metabolite T1 information. In data processing, a novel generalized series model was used to remove water and subcutaneous lipid signals; a low‐rank tensor model with prelearned subspaces was used to reconstruct the variable‐flip‐angle metabolite signals jointly from the noisy data.

Results

The proposed method was evaluated using both phantom and healthy subject data. Phantom experimental results demonstrated that high‐quality 3D metabolite T1 maps could be obtained and used for correction of T1 saturation effects. In vivo experimental results showed metabolite T1 maps with a large spatial coverage of 240 × 240 × 72 mm3 and good reproducibility coefficients (< 11%) in a 14.5‐min scan. The metabolite T1 times obtained ranged from 0.99 to 1.44 s in gray matter and from 1.00 to 1.35 s in white matter.

Conclusion

We successfully demonstrated the feasibility of 3D metabolite T1 mapping within a clinically acceptable scan time. The proposed method may prove useful for both T1 mapping of brain metabolites and correcting the T1‐weighting effects in quantitative metabolic imaging.
Effects of financial toxicity and socioeconomic status on MRI follow‐up time in multiple sclerosis
Authors: Agarwal Rishab , Risk Benjamin B. , Sandlin David S. , Mulamalla Anurag R. , Sadigh Gelareh , Allen Jason W. , Fleischer Candace C.
Published: June 2024

Background and Purpose

Multiple sclerosis (MS) is associated with high risk for financial toxicity. Repeated magnetic resonance imaging (MRI) is standard of care but can present a financial burden for patients with MS. The purpose of this study was to identify relationships between financial factors and socioeconomic status (SES) on brain MRI follow‐up time for individuals with MS.

Methods

Brain MRI scans performed during an 18‐month period were reviewed. Inclusion criteria were individuals ≥18 years old with confirmed MS diagnosis and repeated brain MRI. MRI follow‐up time (days) was calculated as the difference between subsequent scans. Demographic and clinical factors were obtained from electronic medical records. Financial factors were determined from hospital records. The area deprivation index (ADI) was used as a metric for SES. Group‐wise comparisons of MRI follow‐up time were performed as a function of demographic, clinical, and financial factors. Linear regression analyses were used to identify associations between MRI follow‐up time, financial liability, and ADI.

Results

The final cohort included 92 individuals with MS and repeated brain MRI. MRI follow‐up times were significantly lower for individuals on Tysabri (p = .003), but no other group‐wise differences were observed. For individuals with non‐zero financial liability (n = 38), a significant positive association was observed between MRI follow‐up time and amount of financial liability for the initial scan (R = 0.486, p = .002), controlling for demographic and clinical factors.

Conclusions

Financial liability related to the cost of MRI was significantly associated with longer MRI follow‐up times in MS.
Disentangling gender and social difference for just and transformative biocultural approaches
Authors: Díaz‐Reviriego Isabel , Torralba Mario , Vizuete Beatriz , Ortiz‐Przychodzka Stefan , Pearson Jasmine , Heindorf Claudia , LLanque Zonta Aymara , Oteros‐Rozas Elisa
Published: June 2024

Advancing research and practice that recognize diverse worldviews, knowledge systems, and value orientations is essential to enable transformative change towards sustainability. Biocultural approaches recognize the diverse ways in which people relate to nature, offering a potential pathway for sustainability transformations. However, recent scholarship on biocultural approaches to sustainability has highlighted that social aspects such as equity and justice have not been substantively addressed, whereby gender issues have been overlooked to a great extent.

Through qualitative content analysis, this review synthesizes the conceptualizations of gender and social difference within the literature on biocultural approaches to sustainability published in English and Spanish.

The biocultural literature predominantly focuses on describing knowledge and management practices, neglecting power and gender relations that affect access and control over resources, and how different axes of social difference matter across different social‐ecological contexts. Overall, we found that gender considerations within the literature reviewed do not build upon feminist and gender theories.

Based on these findings, we provide insights into how more nuanced engagements, especially in relation to feminist theories and tools as intersectionality and decolonial perspectives, can allow for more just scholarly efforts to address biocultural relations.

Finally, we draw attention to responsible and engaged praxis towards promoting biocultural approaches that include the diverse perspectives of those who can contribute to transformative change, and which prevent the reinforcement of gender‐based power relations.

Read the free Plain Language Summary for this article on the Journal blog.
Effect of improved electric field distribution on jet motion, fiber morphology, and properties of electrospun thermoplastic polyurethane fibrous membrane
Authors: Li Xiang , Lou Liqin
Published: June 2024

Electric field plays a pivotal role in electrospinning to produce the desired micro and nanofibers, hence, a tricipital‐needle spinneret was developed to improve electric field distribution and productivity in this work. The effects of electric field distribution induced by spinneret configuration on jet motion, fiber morphology, and properties of electrospun TPU fibrous membrane at different applied voltages were investigated by simulation and experiment. The simulation results show that the designed tricipital‐needle spinneret weakens the electric field near the needle tip and strengthens the electric field in the whipping region in comparison to the single‐needle spinneret, exhibiting a relatively uniform electric field distribution. The experimental results demonstrate that the fiber diameter prepared by the tricipital‐needle spinneret at the corresponding voltage is smaller than that of the single‐needle spinneret due to the improved electric field distribution. Moreover, the fibrous membrane prepared by the tricipital‐needle spinneret shows excellent tensile properties (7 MPa tensile stress and 401% breaking elongation), air permeability (85.32 mm s−1) and water vapor permeability (6.7 kg m−2 d−1). Therefore, the electrospinning system with the tricipital‐needle spinneret not only increases the fiber productivity, but also improves the electric field distribution and endows the fibrous membrane with better properties, which can widen the applications of electrospun TPU fibrous membrane and also provides a new approach for the performance design of other electrospun fibers.
Gnathodiaphyseal dysplasia: Diagnostic clues from two fetal cases and literature review
Authors: Cuvelier Vivien , Trost Detlef , Stichelbout Morgane , Michot Caroline , Cormier‐Daire Valérie , Boutry Nathalie , Machet Elise , Vincent‐Delorme Catherine
Published: June 2024

This article presents two fetal cases of gnathodiaphyseal dysplasia (GDD), a rare autosomal dominant disorder, and reviews the relevant literature. The cases involved two fetuses exhibiting bone bowing, which led to the diagnosis of GDD. Genetic testing revealed two de novo variants of the ANO5 gene, confirming the diagnosis. A literature review was conducted to explore GDD's clinical and paraclinical presentation, diagnosis, and management. GDD is a rare but frequently inherited cause of bone fragility and jaw lesions characterized by a gain‐of‐function variant within the ANO5 gene. Clinical manifestations range from recurrent dental infections with mild jaw lesions to severe bone fragility with several fractures associated with large jaw lesions requiring disfiguring surgeries. Diagnostic techniques depend on the context and include targeted genetic testing of ANO5, untargeted molecular analysis with whole‐exome sequencing, or whole‐genome sequencing. This case report highlights the importance of recognizing GDD as a novel cause of bone bowing and fractures during pregnancy. By summarizing the literature, this article contributes to healthcare professionals' knowledge and improves the recognition, diagnosis, and care of patients with GDD.
Interlaminar tensile properties of raw and carbon fiber‐wrapped additively manufactured polyetherimide
Authors: Sankaran Vigneshwaran , Rajan A. John , Selvaraj Senthil Kumaran , Jose Swaminathan , Wilson Vincent H. , Singh K. Arjun , Sahayaraj A. Felix , Patterson Albert E.
Published: June 2024

High‐performance engineering thermoplastics are important emerging materials, particularly when processed using additive manufacturing technologies. One of the most important among these is polyetherimide, also known as PEI or ULTEM. Using the fused filament fabrication (FFF) additive manufacturing (AM) process to form this material is a good option, but it is difficult to control the properties in some cases due to the very high processing temperature compared with most engineering thermoplastics. One way to “even‐out” the properties is to wrap the specimens in continuous glass or carbon fibers embedded in a thermosetting matrix, as this allows strategic placement and orientation of reinforcement. This also complements the natural structure of the FFF‐manufactured materials, helping to minimize the amount of additional weight that needs to be added to a part. To further knowledge in this area, the present study explored and compared the interlaminar tensile strength of FFF‐processed PEI/ULTEM 9085 specimens and compared them with ones wrapped in carbon fibers with a 2‐part resin matrix. Experiments were performed in accordance with the guidelines given in the ASTM D6415 standard and replicated five times. Variations were introduced in thickness of the specimen and raster angle during the manufacturing process to identify the significant impact of the failure. The results show a fall in interlaminar tensile strength with increasing specimen thickness and a very large effect from natural printing defects in the samples. The carbon fiber wrap decreased the ILTS but made the results far more consistent between experimental runs. This study provides a good, replicated dataset on the performance of raw and fiber‐wrapped FFF‐processed ULTEM 9085 and gives insights into the structural behavior of the material that will be useful for use in design decisions and material selection.

Highlights

Polyetherimide, also known as PEI/ULTEM, is a high‐performance engineering thermoplastic.

Explored the interlaminar tensile properties (ILTS) of this material using ASTM D6415.

Raster angle, thickness, and use of fiber wrap were experimental parameters.

Fiber wrap was found to have little effect on strength but made results more consistent.

Results are useful for material selection and design decisions using PEI.
Ethical decision‐making approach of school counseling: A concurrent mixed methods study for taking actions
Authors: Tsega Tigist Wuhib
Published: June 2024

The main purpose of this research was to identify ethical decision‐making approaches in school counseling. The study focused on the experiences of secondary school counselors in Addis Ababa, Ethiopia. A concurrent triangulation mixed methods design was used for getting a complete understanding of ethical decision‐making approaches of school counseling. Forty participants were involved in the quantitative part of the study, while six participated in the qualitative part of the study. For the quantitative aspect, a survey was utilized, and the data were analyzed using tables, frequencies, and percentages. The result showed that participants used variety of approaches to deal with ethical challenges for school counseling, including open discussion, personal sense of morality, and respecting code of students' discipline. However, the least percentage (22.5%, n = 9) has observed for using of code of ethics in counseling profession. In the qualitative part, semi‐structured in‐depth interviews were used to explore the experiences of ethical decision‐making and the meaning of those experiences for secondary school counselors currently practicing at Addis Ababa city. Qualitative data were analyzed by using thematic analysis technique. The major ethical decision‐making approaches identified in school counseling were (a) building a good relationship and guaranteed confidentiality, (b) referral linkage, (c) training for students and collaboration, and (d) life experience and personal sense of morality. The most common meanings attributed to dealing with ethical challenges in school were the urge to share information with to get personal relief, feeling of stress, and gain personal satisfaction from acts of compassion. Implications are forwarded to support school counselors in taking an action for professional development and to promote quality of school counseling practices.
Stabilizing Perovskite Solar Cells Based on 2,2′,7,7′‐Tetrakis(N,N‐DI‐P‐Methoxyphenylamine)‐9,9′‐Spirobifluoren with Perfluoropolyethers
Authors: Xue Xiangying , Yang Weichuang , Ying Zhiqin , Zeng Yuheng , Yang Xi , Ye Jichun
Published: June 2024

Organic–inorganic hybrid perovskites in combination with the hole‐transport material (HTM) 2,2′,7,7′‐tetrakis(N,N‐di‐p‐methoxyphenylamine)‐9,9′‐spirobifluoren (spiro‐OMeTAD) yield impressive power conversion efficiency (PCE) in n–i–p perovskite solar cells (PSC). To ensure sufficient hole extraction from the perovskite absorber to the metal electrode, the lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) doping is considered indispensable to promote spiro‐OMeTAD oxidization and obtain consequently enhanced conductivity. However, LiTFSI‐doped spiro‐OMeTAD usually leads to a reduced stability of PSCs because of the hygroscopic nature of LiTFSI, which further limits its potential commercialization. Herein, a hydrophobic material, namely perfluoropolyethers (PFPEs), is used as surface modifier of doped HTM to improve both efficiency and stability of PSCs. It is revealed that the introduction of PFPE increases the concentration of positive radicals, enhances charge‐carrier transport, and improves stability of PSCs under wetting stress. Moreover, the device based on PFPE achieves a champion PCE of 21.94%. In these findings, valuable insights are provided for the future commercialization of PSCs.
Developing Correlation Between In Silico Molecular Modeling and In Vitro α‐Amylase, Anti‐Cancer and SARS‐COV‐2 Studies of Bis‐Indole Derived Triazine‐Based Thiazolidinone Hybrid Derivatives
Authors: Khan Shoaib , Hussain Rafaqat , Khan Yousaf , Iqbal Tayyiaba , Shoaib Khurram , Jehangir Uzma , Khowdiary M. M. , Felemban Shifa
Published: June 2024

In the era of COVID‐19 most of the marketed drugs have been found with some negative effects as well as with fewer numbers in the market. There is a serious need of an anti‐COVID agent which can maintain the normal body function with fewer or no side effects. For this purpose, hybrid derivatives based on bis‐indole derived triazine based thiazolidinone derivatives (1–12) were successfully synthesized and characterized using various spectroscopic techniques including 1H NMR, 13C NMR and HREI‐MS. All the synthesized bis‐indole derived triazine‐bearing thiazolidinone derivatives were tested for in vitro α‐amylase, cancer cell and SARS‐COV‐2 enzymes under the positive control of Acarbose, Tetrandrine and GC‐376 as standard drugs. All derivatives showed varied range of biological activities against target enzymes having IC50 values ranging from 3.10±0.20 to 25.80±0.20 μM (α‐amylase), 0.20±0.30 to 19.10±0.20 μM (ant‐cancer) and 3.20±0.20 to 16.20±0.30 μM (SARS‐COV‐2), respectively. Specifically, derivatives 1, 3, 6, 8 and 9 were found to significantly active against target enzymes. Furthermore, the molecular docking approach was used to explore the binding interactions established by most active derivatives with the active sites of target enzymes and results corroborated that these active compounds developed several key interactions with the target enzymes and hence enhanced the enzymatic activities. Additionally, ADME prediction for the synthesized compounds were also explored which shows drug likeness of the synthesized compounds.
Insight into the Contact Mechanism of Ag/Al–Si Interface for the Front‐Side Metallization of TOPCon Silicon Solar Cells
Authors: Li Yongsheng , Zhou Rui , Chen Ziwei , Li Yuhang , Cheng Xing , Zhang Bo , Chen Jun , Lin Yuan , Pan Feng
Published: June 2024

For N‐type tunnel‐oxide‐passivated‐contact silicon solar cells, optimal Ag/Al–Si contact interface is crucial to improve the efficiency. However, the specific roles of Ag and Al at the interface have not been clearly elucidated. Hence, this work delves into the sintering process of Ag/Al paste and examines the impact of the Ag/Al–Si interface structure on contact quality. By incorporating TeO2 into PbO‐based Ag/Al paste, the Ag/Al–Si interface structure can be modulated. It can be found that TeO2 accelerates the sintering of Ag powder and increases Ag colloids within glass layer, while it simultaneously impedes the diffusion of molten Al. It leads to a reduced Al content near the Ag/Al–Si interface and a shorter diffusion distance of Al into Si. Notably, it can be demonstrated that the diffusion of Al in Si layer is more effective to reduce the contact resistance than the precipitation of Ag colloids. Therefore, the PbO‐based Ag/Al paste, which favors Al diffusion, leads to solar cells with lower contact resistance and series resistance, higher fill factor, and superior photoelectric conversion efficiency. In brief, this work is significant for optimizing metallization of silicon solar cells and other semiconductor devices.
Improving the Water Resistance of Bi‐Based Perovskite‐Inspired Materials for Vapor‐Phase Photocatalytic Overall Water Splitting
Authors: Chacón‐García Antonio J. , Baldovi Herme G. , Pols Mike , Tao Shuxia , Calero Sofia , Navalón Sergio , Vitorica‐Yrezabal Iñigo J. , Rodríguez‐Diéguez Antonio , García Hermenegildo , Horcajada Patricia , Pérez Yolanda
Published: June 2024

Lead halide perovskites are well known for their exceptional photophysical and electronic properties, which have placed them at the forefront of challenging optoelectronic applications and solar‐to‐fuel conversion. However, their air/water instability, combined with their toxicity, is still a critical problem that has slowed down their commercialization. In this sense, bismuth‐based halide derivatives attract much interest as a potentially safer, air‐stable alternative. Herein, a novel Bi‐based perovskite‐inspired material, IEF‐19 (IEF stands for IMDEA Energy Framework), which contains a bulky aromatic cation (1,5‐diammonium naphthalene), is prepared. Additionally, an N‐alkylation strategy is successfully employed to achieve four water‐stable perovskite‐inspired materials, which contains diammonium naphthalene cations that are tetra‐alkylated by methyl, ethyl, propyl, and butyl groups. Moreover, computational studies are performed to gain a deeper understanding of the intrinsic structural stability and affinity of water molecules for Bi‐based perovskite‐inspired materials. Importantly, the air‐ and water‐stable IEF‐19‐Et (i.e., stable at least 12 months under ambient conditions and 3 weeks in contact with water) is found to be an active photocatalyst for vapor‐phase overall water splitting in the absence of any sacrificial agent under both ultraviolet–visible or simulated sunlight irradiation. This material exhibits an estimated apparent quantum yield of 0.08% at 400 nm, partially explained by its adequate energy band level diagram.
Ermüdungsfestigkeit von Betonfahrbahnplatten bei Verbundgroßbrücken
Authors: Stempniewski Lena , Kuhlmann Ulrike
Published: June 2024

Im Stützbereich von Verbundgroßbrücken entstehen aufgrund der negativen Momentenbeanspruchung Zugbeanspruchungen in der Betonfahrbahnplatte, die zu Rissen führen. Im Querrahmenabstand werden stählerne Kragträger unter der Fahrbahn u. a. zur Auflagerung von Teilfertigteilen angeordnet, sodass die Fahrbahnplatte überwiegend in Längsrichtung spannt. Typischerweise haben diese Fahrbahnplatten hohe Längsbewehrungsgrade, aber keine Querkraftbewehrung. Über die infolge der Zugbeanspruchung gerissene Fahrbahnplatte müssen aufgrund lokaler Radlasten durch wechselnde Verkehrsbelastung zyklisch veränderliche Querkräfte zu den Querträgern abgetragen werden. Bislang lagen keine Versuche vor, die die Ermüdungsfestigkeit der gerissenen Betonfahrbahnplatte abbilden. Auf Basis von Versuchen aus der Literatur (wobei es bislang ausschließlich aussagekräftige Versuche ohne Längszugbeanspruchung gab) sowie eigenen Experimenten (mit Längszugbeanspruchung) wurde eine Datenbank aufgebaut, anhand derer Wöhlerlinien abgeleitet werden konnten und die die gezielte Auswertung des Einflusses verschiedener Parameter erlaubte. Da die Ermüdungsfestigkeit von Stahlbetonbauteilen ohne Querkraftbewehrung von der statischen Tragfähigkeit abhängig ist, wird insbesondere auch auf den Einfluss der Streuung dieser auf die Ermüdungsfestigkeit eingegangen. Basierend auf den Ergebnissen und dem aktuellen Stand der Normung wird ein Bemessungskonzept zur Ermüdungsfestigkeit der Betonfahrbahnplatte vorgestellt.
Quantification of phenol degradation using hydrodynamic cavitation‐based packed bed reactor based on glass balls
Authors: Mohod Ashish V. , Clemente Danilo B. , Klanovicz Natalia , Moreira Paulo F. , Bagal Manisha V. , Teixeira Antonio Carlos S. C. , Giudici Reinaldo
Published: June 2024

The current study presents a novel and effective cavitation technique for the degradation of phenol using a hydrodynamic cavitation‐based packed bed reactor (HCPBR). Several operational parameters, including fluid velocity, hydrogen peroxide (H2O2) generation (18.06 μM of H2O2 in 60 min), and initial phenol concentration, have been studied using a HCPBR. The effective parameters for phenol degradation were found to be a fluid velocity of 85.15 m/s and an initial phenol concentration of 20 ppm. It was also noted that the presence of a glass marble‐bed (15.35%) in the cavitation reactor exhibits a substantial effect on the degradation of phenol compared to the absence of a glass marble‐bed (2.91%). The investigation also examined the effect of combining hydrodynamic cavitation with chemical oxidation processes, specifically H2O2, persulfate (Na2S2O8 and K2S2O8), and titanium dioxide, on the extent of phenol degradation. Persulfate was shown to have a significant effect on phenol degradation at 1 g/L. To clarify if free radical attack is the driving force behind degradation, the impact of radical scavengers such as n‐butanol has also been examined. Toxicological assessments revealed that, for lentil meristematic cells, the therapy was quite cytotoxic, but it needs to be improved to eliminate its genotoxic side effects. Overall, the experiment clearly demonstrated the effectiveness of the HCPBR for phenol degradation.
Nominal CaAl2Pt2 and Ca2Al3Pt – two new Intermetallic Compounds in the Ternary System Ca−Al−Pt
Authors: Engel Stefan , Koch Marcus , Janka Oliver
Published: June 2024

Single crystals of CaAl2Pt2, Ca2Al3Pt and Ca2AlPt2 were initially observed in an attempt to synthesize Ca3Al4Pt4. Their structures were determined using single‐crystal X‐ray diffraction experiments. While nominal CaAl2Pt2 (CaBe2Ge2 type, P4/nmm, a=426.79(2), c=988.79(6) pm, wR2=0.0679, 246 F2 values and 18 variables) and Ca2Al3Pt (Mg2Cu3Si type, P63/mmc, a=561.46(5), c=876.94(8) pm, wR2=0.0664, 214 F2 values and 13 variables) exhibit Al/Pt mixing, for Ca2AlPt2 (Ca2Ir2Si type, C2/c, a=981.03(2) b=573.74(1), c=772.95(2) pm, β=101.862(1)° wR2=0.0307, 2246 F2 values and 25 variables) no mixing was observed. Subsequently, the nominal compositions were targeted with synthetic attempts from the elements using arc‐melting and annealing techniques. For CaAl2Pt2 and Ca2Al3Pt always multi‐phase mixtures were observed while Ca2AlPt2 could be obtained as almost X‐ray pure material. Quantum‐chemical calculations were used to investigate the charge transfer in these compounds rendering them polar intermetallics with a designated [AlxPty]δ− polyanion and Caδ+ cations in the cavities of the polyanions.
Big Data in Restaurant Management: Unsupervised Modelling of Ticket Data and Environmental Variables for Sales Forecasting
Authors: Gómez-Talal Ismael , González-Serrano Lydia , Talón-Ballestero Pilar , Rojo-Álvarez José Luis
Published: June 2024

Revenue Management (RM) is one of the challenges facing the restaurant industry, mainly due to the lack of technology in this sector and the lack of data. Forecasting is the most valuable input of RM. For this reason, the main objective of this research is the proposal of a sales forecasting model based on the data provided by the tickets of a restaurant to extract information that allows the correct management of price and capacity. A system based on an unsupervised Machine Learning (ML) model was implemented to analyze the information and visualize the relationships between dishes and temperatures. The developed system uses unsupervised ML techniques, such as multicomponent analysis and bootstrap sampling, to identify and visualize statistically relevant relationships between data. This study provides a simple and understandable solution to improve management and maximize profits to support restaurant managers’ decision-making.
The Impact of the Pandemic on the P2P Market for Tourist Accommodation
Authors: Benítez-Aurioles Beatriz
Published: June 2024

This paper examines the impact of the COVID-19 pandemic, which was declared in March 2020, on the peer-to-peer (P2P) market for tourist accommodation, focusing on supply, demand, and prices. By analyzing monthly data between February 2019 to February 2021 from 15 cities across Europe, North America and Australia, the study provides insights into the changes experienced in the P2P market during the pandemic. The ensuing findings indicate a significant decline in both supply and demand. The number of reviews, serving as a proxy for demand, shows a clear downward trend that reflects the reduced travel activity during the pandemic. In parallel, the number of listings decreases, highlighting the adaptability of supply to demand shocks. The pandemic also led to a notable decrease in prices, as observed in the analysis of price data and backed by previous studies. Professional hosts demonstrate their capacity to adapt by adjusting prices and minimum stays to attract a stable demand. This finding aligns with previous research that displays the strategic responses of professional hosts to market conditions. Furthermore, the results contribute to the existing literature by providing empirical evidence of the simultaneous decline in supply and demand, leading to lower prices and income for hosts. The strategic responses of professional hosts make evident their adaptability in the P2P market.
Lexical Competence in New Digital Environments: The Metaverse and Its Application to Tourism Science
Authors: Serra-Pfennig Isabel
Published: June 2024

This work is based, on the one hand, on the experience with the metaverse carried out in an exhibition that took place at the Matadero Contemporary Creation Center in Madrid (09.22.2022–January 29, 2023), titled Metaverses, Realities in transition.
Assessing Tourists’ Perception of ‘Smartness’ in a Destination: A Case Study of Tenerife Island
Authors: Mesegue-Basallo Miquel Armand , Marti-Ochoa Julia , Ferrer-Rosell Berta , Martin-Fuentes Eva
Published: June 2024

Smart Tourism Destinations (STDs) have been presented as a key element to boost the tourism sector and keep it adapted to the changing needs of governments, local inhabitants and tourists. The Spanish government launched the STDs’ Network in 2013 to adapt Spanish tourist destinations to evolving needs. The program aims to create customized, accessible experiences using technology and innovation while ensuring sustainability. To be recognized as a STD, destinations must meet 80% of requirements set, classified into governance, innovation, technology, universal accessibility, and sustainability. The study aims to examine tourists’ awareness of the smart characteristics of destinations, by analyzing user-generated content. The data collection focuses on Tenerife Island's top attractions and includes reviews from the English section of TripAdvisor's “things to do” category. The analysis reveals changes in tourists’ comments and highlights that tourists are aware of some indicators and objectives such as accessibility. The article sheds light on the concept of STDs and their implications for the tourism industry.
A Modern Approach to Transition Analysis and Process Mining with Markov Models in Education
Authors: Helske Jouni , Helske Satu , Saqr Mohammed , López-Pernas Sonsoles , Murphy Keefe
Published: June 2024

This chapter presents an introduction to Markovian modelling for the analysis of sequence data. Contrary to the deterministic approach seen in the previous sequence analysis chapters, Markovian models are probabilistic models, focusing on the transitions between states instead of studying sequences as a whole. The chapter provides an introduction to this method and differentiates between its most common variations: first-order Markov models, hidden Markov models, mixture Markov models, and mixture hidden Markov models. In addition to a thorough explanation and contextualisation within the existing literature, the chapter provides a step-by-step tutorial on how to implement each type of Markovian model using the R package seqHMM. The chapter also provides a complete guide to performing stochastic process mining with Markovian models as well as plotting, comparing and clustering different process models.
Predictive Modelling in Learning Analytics: A Machine Learning Approach in R
Authors: Jovanovic Jelena , López-Pernas Sonsoles , Saqr Mohammed
Published: June 2024

Prediction of learners’ course performance has been a central theme in learning analytics (LA) since the inception of the field. The main motivation for such predictions has been to identify learners who are at risk of low achievement so that they could be offered timely support based on intervention strategies derived from analysis of learners’ data. To predict student success, numerous indicators, from varying data sources, have been examined and reported in the literature. Likewise, a variety of predictive algorithms have been used. The objective of this chapter is to introduce the reader to predictive modelling in LA, through a review of the main objectives, indicators, and algorithms that have been operationalized in previous works as well as a step-by-step tutorial of how to perform predictive modelling in LA using R. The tutorial demonstrates how to predict student success using learning traces originating from a learning management system, guiding the reader through all the required steps from the data preparation all to the evaluation of the built models.
χc2 tensor meson transition form factors in the light front approach
Authors: Babiarz Izabela , Pasechnik Roman , Schäfer Wolfgang , Szczurek Antoni
Published: June 2024

Abstract

We continue our work on the light-front formulation of quarkonium γ∗γ transition form factors, extending the formalism to JPC = 2++ tensor meson states. We present an analysis of γ∗γ → χc2 transition amplitude and the pertinent helicity form factors. Our relativistic formalism is based on the light-front quark-antiquark wave function of the quarkonium. We calculate the two-photon decay width as well as three independent γ∗γ transition form factors for Jz = 0, 1, 2 as a function of photon virtuality Q2. We compare our results for the two-photon decay width to the recently measured ones by the Belle and BES III collaborations. Even when including relativistic corrections, a very small Γ(λ = 0)/Γ(λ = 2) ~ 10−3 ratio is found which is beyond present experimental precision. We also present the form factors as a function of photon virtuality and compare them to the sparse experimental data on the so-called off-shell width. The formalism presented here can be used for other 2++ mesons, excited charmonia or bottomonia or even light $$ q\overline{q} $$
q

q
¯

-mesons.
EphB2 activation in neural stem cells in the basolateral amygdala facilitates neurogenesis and enhances long-term memory
Authors: Agarwal Karishma , Lamprecht Raphael
Published: June 2024

Many brain diseases lead to a reduction in the number of functional neurons and it would be of value to be able to increase the number of neurons in the affected brain areas. In this study, we examined whether we can promote neural stem cells to produce mature neurons and whether an increase in the mature neurons can affect cognitive performance. We detected that the EphB2 receptor is localized in immature basolateral amygdala (BLA) neurons. We therefore aimed to increase the level of EphB2 activity in neural stem cells (NSCs) in the BLA and examine the effects on the production of mature neurons and cognition. Toward that end, we utilized a photoactivatable EphB2 construct (optoEphB2) to increase EphB2 forward signaling in NSCs in the BLA. We revealed that the activation of optoEphB2 in NSCs in the BLA increased the level of immature and mature neurons in the BLA. We further found that activation of optoEphB2 in BLA NSCs enhanced auditory, but not contextual, long-term fear memory formation. Impairing EphB2 forward signaling did not affect the level of immature and mature neurons in the BLA. This study provides evidence that NSCs can be promoted to produce mature neurons by activating EphB2 to enhance specific brain functions.
Applicability of Deep Learning to Dynamically Identify the Different Organs of the Pelvic Floor in the Midsagittal Plane
Authors: García-Mejido José Antonio , Solis-Martín David , Martín-Morán Marina , Fernández-Conde Cristina , Fernández-Palacín Fernando , Sainz-Bueno José Antonio
Published: June 2024

Introduction and Hypothesis

The objective was to create and validate the usefulness of a convolutional neural network (CNN) for identifying different organs of the pelvic floor in the midsagittal plane via dynamic ultrasound.

Methods

This observational and prospective study included 110 patients. Transperineal ultrasound scans were performed by an expert sonographer of the pelvic floor. A video of each patient was made that captured the midsagittal plane of the pelvic floor at rest and the change in the pelvic structures during the Valsalva maneuver. After saving the captured videos, we manually labeled the different organs in each video. Three different architectures were tested—UNet, FPN, and LinkNet—to determine which CNN model best recognized anatomical structures. The best model was trained with the 86 cases for the number of epochs determined by the stop criterion via cross-validation. The Dice Similarity Index (DSI) was used for CNN validation.

Results

Eighty-six patients were included to train the CNN and 24 to test the CNN. After applying the trained CNN to the 24 test videos, we did not observe any failed segmentation. In fact, we obtained a DSI of 0.79 (95% CI: 0.73 – 0.82) as the median of the 24 test videos. When we studied the organs independently, we observed differences in the DSI of each organ. The poorest DSIs were obtained in the bladder (0.71 [95% CI: 0.70 – 0.73]) and uterus (0.70 [95% CI: 0.68 – 0.74]), whereas the highest DSIs were obtained in the anus (0.81 [95% CI: 0.80 – 0.86]) and levator ani muscle (0.83 [95% CI: 0.82 – 0.83]).

Conclusions

Our results show that it is possible to apply deep learning using a trained CNN to identify different pelvic floor organs in the midsagittal plane via dynamic ultrasound.
Arbeitsschutz für Rechtsmedizinerinnen während Schwangerschaft und Stillzeit – Teil 1: arbeitsrechtliche Rahmenbedingungen
Authors: Schäffer Benno , Ochmann Uta , Graw Matthias
Published: June 2024

Hintergrund

Der Arbeitsschutz für Rechtsmedizinerinnen ist sowohl auf europäischer als auch auf nationaler Ebene in zahlreichen Rechtsvorschriften geregelt. Ein besonderer Schutz besteht in Schwangerschaft und Stillzeit.

Methode

Die Arbeit beruht auf selektiver Literaturrecherche. Der Schwerpunkt liegt auf dem Thema des Mutterschutzes.

Ergebnisse

Schwangere und Stillende werden insbesondere durch das Mutterschutzgesetz (MuSchG) geschützt. Dieses regelt u. a. Beschäftigungszeit, Schutzfristen und Kündigungsverbot.

Diskussion

Mutterschützende Arbeitszeitbestimmungen setzen eine ordnungsgemäße Arbeitszeiterfassung voraus. Arbeitgeber sollten geschlechtsspezifische Unterschiede bei der Gefährdungsbeurteilung berücksichtigen. Betriebsärzte können hierbei unterstützen.
Semilattices of stratified extensions
Authors: Renshaw James , Warhurst William
Published: June 2024

Grillet (Semigroup Forum 50:25–36, 1995) introduced the concept of stratified semigroups as a kind of generalisation of finite nilsemigroups. We extend Grillet’s ideas by introducing the notion of the base of a semigroup and show that a semigroup is stratified if and only if its base is either empty or consists of only the zero element. The general structure of semigroups with non-trivial bases is studied and we show that these can be described in terms of ideal extensions of semigroups by stratified semigroups. We consider certain types of group-bound semigroups and also ideal extensions of Clifford semigroups, and show how to describe them as semilattices of ideal extensions by stratified semigroups and provide a number of interesting examples.