bluuebunny/crossref_metadata_2025 huggingface dataset:
The impacts of seasonal variation and climate on food utilization in a population of critically endangered cotton‐top tamarins (Saguinus oedipus) in Colombia: A 22‐year longitudinal study
Authors: Savage A. , Snowdon C. T. , Soto L. , Castro J. , Medina F. , Emeris G. , Garcia L. C. , Guillen R.
Published: July 2022

To examine how precipitation patterns and climate change impact feeding choices made by a population of critically endangered cotton‐top tamarins (Saguinus oedipus), we examined 22 years of feeding data (1999–2020) from 21 groups collected at Parque Natural Regional Bosque Seco El Ceibal Mono Tití in Santa Catalina, Colombia. We describe the diet and examine the role of seasonal rainfall and annual variation in rainfall on diet. Rainfall is highly seasonal (mean annual rainfall 1562 mm [range 940–2680 mm]) with a dry, early rainy, and late rainy season in each year. Over 80 species of plants formed part of the fruit, nectar, and exudate components of the diet. Fruits, although available year‐round, were more commonly available and consumed during the late rainy seasons (August–November). Exudates were consumed more frequently in the dry season (December–March) and invertebrate consumption was stable across the year. Nectar feeding from a single species (Combretum fruticosum) peaked in November. Rainfall varied over the years, with 13 years exceeding the 99% confidence intervals for mean rainfall. Ten of these extreme years (both drought and extremely wet) occurred in the last 11 years. Fruit consumption did not vary between extreme and average years, but cotton‐top tamarins consumed more invertebrates and exudates in wet years. Presently, cotton‐top tamarins appear to be able to cope with these extreme variations in rainfall due to their highly varied diet. However, the forests that these primates depend upon for survival are threatened by human exploitation making it critically important to maintain a generalist feeding strategy for survival as many fruiting trees that compose a large proportion of the diet are removed. As conservation efforts continue, plant species consumed by cotton‐top tamarins provide useful data when selecting species for habitat restoration programs.
Development of an optimized preoperative computed tomography imaging checklist for endoscopic sinus surgery utilizing a systematic review of the literature and the modified Delphi method
Authors: Leong Stephen , Yang Nathan , Ray Amrita , Akbar Nadeem , Colley Patrick M. , Signore Anthony Del , Eloy Jean Anderson , Govindaraj Satish , Gudis David A. , Helman Samuel , Hsueh Wayne , Iloreta Alfred‐Marc , Kacker Ashutosh , Lieberman Seth , Pearlman Aaron N. , Schaberg Madeleine R. , Tabaee Abtin , Overdevest Jonathan B. ,   New York Rhinology Consortium
Published: July 2022

Background

Critical review of computed tomography (CT) imaging is essential in preoperative planning for endoscopic sinus surgery. In this study, we used a systematic review and a modified Delphi method to develop a comprehensive checklist that facilitates preoperative review of sinus CT imaging.

Methods

We performed a systematic review of PubMed, Embase, CINAHL, Cochrane, and Web of Science databases to identify existing checklists developed to evaluate sinus CT imaging. An inclusive list of items from these checklists was compiled and a modified Delphi methodology was used to assign ranked priority. The Delphi process involved 14 rhinologists and had three phases: an initial survey with Likert priority (scale of 1–9) and two rounds of live discussions followed by survey to confirm consensus.

Results

Ninety‐seven possible checklist items were identified from a systematic review and panelist input. On initial survey, 63 items reached a consensus score of 7+, and 13 items had near consensus scores between 6 and 7; two of these 13 borderline items were retained after subsequent panelist discussion. The resulting items were consolidated into an 11‐item disease checklist and a 24‐item anatomical checklist; the anatomical checklist was further divided into six subsections: nasal cavity, maxillary, ethmoid, sphenoid, frontal, skull base, and orbit. Additionally, panelists identified six core aspects of patient history to consider prior to surgery.

Conclusions

After establishing content validity through a systematic literature review and a modified Delphi method, we developed a comprehensive checklist for preoperative sinus CT imaging review; implementation and evaluation of validity among trainees will suggest overall utility.
Surface Modification of Erythrocytes with Lipid Anchors: Structure–Activity Relationship for Optimal Membrane Incorporation, in vivo Retention, and Immunocompatibility
Authors: Gaikwad Hanmant , Wang Guankui , Li Yue , Bourne David , Simberg Dmitri
Published: July 2022

Red blood cells (RBCs) are natural carriers for sustained drug delivery, imaging, and in vivo sensing. One of the popular approaches to functionalize RBCs is through lipophilic anchors, but the structural requirements for anchor stability and in vivo longevity remain to be investigated. Using fluorescent lipids with the same cyanine 3 (Cy3) headgroup but different lipid chain and linker, the labeling efficiency of RBCs and in vivo stability are investigated. Short‐chain derivatives exhibited better insertion efficiency, and mouse RBCs are better labeled than human RBCs. Short‐chain derivatives demonstrate low retention in vivo. Derivatives with ester bonds are especially unstable, due to removal and degradation. On the other hand, long‐chain, covalently linked derivatives show remarkably long retention and stability (over 80 days half life in the membrane). The clearance organs are liver and spleen with evidence of lipid transfer to the liver sinusoidal endothelium. Notably, RBCs modified with PEGylated lipid show decreased macrophage uptake. Some of the derivatives promote binding of antibodies in human plasma and mouse sera and modest increase in complement deposition and hemolysis, but these do not correlate with in vivo stability of RBCs. Ultra‐stable anchors can enable functionalization of RBCs for drug delivery, imaging, and sensing.
Site‐Selective (Z)‐α‐Borylalkenyl Copper Systems for Nucleophilic Stereodefined Allylic Coupling
Authors: Pujol Mireia , Maza Ricardo J. , Salvado Oriol , Carbó Jorge J. , Fernández Elena
Published: July 2022

1,1‐Diborylalkenes can be transformed into (Z)‐skipped dienes through CuI‐phosphine catalyzed allylic coupling reactions. The energetically preferred formation of (Z)‐α‐borylalkenyl copper (I) species and the subsequent nucleophilic attack, explains the stereoselective nucleophilic substitution with allyl bromides. The eventual treatment of (Z)‐skipped dienes with NaOtBu promotes cyclization/aromatization patterns via enyne intermediates.
Blending the Optical and Redox Properties of Oligoynes and Boron Difluoride Formazanates
Authors: Dhindsa Jasveer S. , Cotterill Erin L. , Buguis Francis L. , Anghel Michael , Boyle Paul D. , Gilroy Joe B.
Published: July 2022

Oligoynes and polyynes are 1D chains of conjugated sp‐hybridized carbon atoms consisting of alternating single and triple bonds. Their stability rapidly decreases with increasing chain length beyond only a few repeating units. Design strategies, such as the use of bulky end‐capping groups, allow for their characterization and isolation while not contributing significantly to their physical properties. In this study, we incorporate redox‐active BF2 formazanate dyes (BF2) as end‐caps to prepare symmetric (BF2−[C≡C]n−BF2) and asymmetric (BF2−[C≡C]n−Si(iPr)3) families of oligoynes containing up to 10 alkyne units. In doing so, we introduce stable oligoynes that possess a blend of optical and redox properties that cannot be achieved by either oligoynes or BF2 formazanates individually (e.g., panchromatic absorption, multiple and tunable reversible redox waves). This approach is transferable to other functional end‐caps to facilitate the preparation of π‐conjugated materials with utility in the organic electronics arena.
Recent Advances in Single‐Junction Organic Solar Cells
Authors: Yao Huifeng , Hou Jianhui
Published: July 2022

Single‐junction organic solar cells (OSCs) have made significant progress in recent years. Innovations in material design and device optimization have improved the power conversion efficiencies to over 19 %. In this Minireview, based on recent advances, we discuss molecular design strategies to tune the absorption spectrum, energy level, and intermolecular aggregation as well as highlight the role of molecular electrostatic potential in decreasing energy loss. Then, we introduce the latest progress in four types of OSCs composed of different donor:acceptor combinations: polymer donor:small‐molecule acceptor, all‐polymer, all‐small‐molecule, and small‐molecule donor:polymer acceptor. Finally, the challenges of OSCs in practical applications, including material cost, stability, and multi‐function integration, are discussed.
Identification and Structure Analysis of an Unusual Halohydrin Dehalogenase for Highly Chemo‐, Regio‐ and Enantioselective Bio‐Nitration of Epoxides
Authors: Wang Hui‐Hui , Wan Nan‐Wei , Miao Run‐Ping , He Cheng‐Li , Chen Yong‐Zheng , Liu Zhi‐Qiang , Zheng Yu‐Guo
Published: July 2022

We report the discovery of an unusual halohydrin dehalogenase, HHDHamb, that can work under relatively low acidic conditions and extremely low temperatures for the bio‐nitration of epoxides using nitrite as a nitrating agent. The bio‐nitration strategy exhibits high chemo‐, regio‐, and enantioselectivity, catalyzing the kinetic resolution of various epoxides to enantiopure β‐nitroalcohols with nitro‐bearing stereocenters in up to 41 % isolated yield and >99 % enantiomeric excess (ee). Additionally, the bio‐nitration method displays a high reaction efficiency and can be performed on a gram scale. We also solved the crystal structure of HHDHamb to understand the possible structural determinants of chemoselectivity control in the bio‐nitration reaction.
Semisynthesis of Homogeneous, Active Granulocyte Colony‐Stimulating Factor Glycoforms
Authors: Kerul Lukas , Schrems Maximilian , Schmid Alanca , Meli Rajeshwari , Becker Christian F. W. , Bello Claudia
Published: July 2022

Granulocyte colony stimulating factor (G‐CSF) is a cytokine used to treat neutropenia. Different glycosylated and non‐glycosylated variants of G‐CSF for therapeutic application are currently generated by recombinant expression. Here, we describe our approaches to establish a first semisynthesis strategy to access the aglycone andO‐glycoforms of G‐CSF, thereby enabling the preparation of selectively and homogeneously post‐translationally modified variants of this important cytokine. Eventually, we succeeded by combining selenocysteine ligation of a recombinantly produced N‐terminal segment with a synthetic C‐terminal part, transiently equipped with a side‐chain‐linked, photocleavable PEG moiety, at low concentration. The transient PEGylation enabled quantitative enzymatic elongation of the carbohydrate at Thr133. Overall, we were able to significantly reduce the problems related to the low solubility and the tendency to aggregate of the two protein segments, which allowed the preparation of four G‐CSF variants that were successfully folded and demonstrated biological activity in cell proliferation assays.
Circularly Polarized Luminescence in a Möbius Helicene Carbon Nanohoop**
Authors: Malinčík Juraj , Gaikwad Sudhakar , Mora‐Fuentes Juan P. , Boillat Marc‐Aurèle , Prescimone Alessandro , Häussinger Daniel , Campaña Araceli G. , Šolomek Tomáš
Published: July 2022

We present the first helicene carbon nanoohop that integrates a [6]helicene into [7]cycloparaphenylene. The [6]helicene endows the helicene carbon nanohoop with chiroptical properties and configurational stability typical for higher helicenes, while the radially conjugated seven para‐phenylenes largely determine the optoelectronic properties. The structure of the helicene carbon nanoohop was unambiguously characterized by NMR, MS and X‐ray analysis that revealed that it possesses a topology of a Möbius strip in the solid state and in solution. The chirality transfers from the [6]helicene to the para‐phenylenes and leads to a pronounced circular dichroism and bright circularly polarized luminescence, which is affected by the structural topology of the nanohoop.
Design and Growth of Branched Organic Crystals: Recent Advances and Future Applications
Authors: Shi Ying‐Li , Lv Qiang , Tao Yi‐Chen , Ma Ying‐Xin , Wang Xue‐Dong
Published: July 2022

The rapid development of information technology has resulted in a growing demand for low‐dimensional photonic materials. Organic semiconductor materials play an important role in various photonic devices due to their adjustable physicochemical properties, while individual organic crystals do not exhibit the desired performance due to the limitations of their simple structure. Branched organic crystals with inherent multichannel characteristics based on π‐conjugated molecules are favorable components in optoelectronics. However, the preparation of branched organic crystals still faces great challenges before they can be applied in integrated optoelectronic devices. In this Review, the development and representative examples of branched organic crystals in terms of molecular design, synthesis, and advanced applications are discussed. We also provide a summary and outlook for the direction of future research on branched organic crystals as excellent candidates in photonic integrated circuits.
On the Bonding Nature in the Crystalline Tri‐Thorium Cluster: Core‐Shell Syngenetic σ‐Aromaticity
Authors: Lin Xuhui , Mo Yirong
Published: July 2022

A unique thorium‐thorium bond was observed in the crystalline tri‐thorium cluster [{Th(η8‐C8H8)(μ3‐Cl)2}3{K(THF)2}2]∞, though the claim of σ‐aromaticity for Th3bond has been questioned. Herein, a new type of core–shell syngenetic bonding model is proposed to describe the stability of this tri‐thorium cluster. The model involves a 3c–2e bond in the Th3core and a multicentered (ThCl2)3charge‐shift bond with 12 electrons scattering along the outer shell. To differentiate the strengths of the 3c–2e bond and the charge‐shift bond, the block‐localized wavefunction (BLW) method which falls into the ab initio valence bond (VB) theory is employed to construct a strictly core/shell localized state and its contributing covalent resonance structure for the Th3core bond. By comparing with the σ‐aromatic H3+and nonaromatic Li3+, the computed resonance energies and extra cyclic resonance energies confirm that this Th3core bond is truly delocalized and σ‐aromatic.
Nonisothermal cure behavior and kinetics of cerium‐doped Fe3O4/epoxy nanocomposites
Authors: Jouyandeh Maryam , Ganjali Mohammad Reza , Rezapour Morteza , Mohaddespour Ahmad , Jabbour Karam , Vahabi Henri , Rabiee Navid , Habibzadeh Sajjad , Formela Krzysztof , Saeb Mohammad Reza
Published: July 2022

How does the cerium (Ce) doping in ferrimagnetic magnetite (Fe3O4) affect the crosslinking state and kinetics of epoxy crosslinking with amine curing agents? To answer this question, we electrochemically synthesized nanoparticles of Ce–Fe3O4 and characterized them by FTIR, XRD, FE‐SEM, EDX, TEM, and XPS analyses. The presence of Ce atoms in Fe3O4 crystalline lattice increased the surface area and active hydroxyl sites of the prepared magnetic nanoparticles (MNPs) associated with partial shrinkage of molecular lattice. The MNPs uniformly dispersed in epoxy resin and unconditionally tagged epoxy nanocomposites as Excellent cured systems. The effect of lanthanide doping on the cure kinetics of epoxy with amine was explored applying nonisothermal DSC and model‐free kinetic approaches, signifying that Ce–Fe3O4 nanoparticles facilitated epoxy ring opening by intensification of etherification reaction whatever the heating rate. Even at very low loading of Ce–Fe3O4 nanoparticles into the epoxy (0.1 wt.%), the average apparent activation energy significantly decreased by ≈10%. This outcome would highlight the role of crosslinking on the ultimate properties, such as anticorrosive and/or self‐healing characteristics contributed by Ce‐doped nanoparticles once added to epoxy coating formulation.
Electronic and optical properties of Nb/V‐doped WS2 monolayer: A first‐principles study
Authors: Kumar Vipin , Mishra Rajneesh Kumar , Kumar Pushpendra , Gwag Jin Seog
Published: July 2022

The electronic, dielectric, and optical properties of pure and Nb/V‐doped WS2 monolayer are being investigated using the first‐principles density functional theory (DFT). The electronic band structure calculations reveal that the pure and doped WS2 monolayer is a direct band gap semiconductor. It is seen that the doping not only slightly reduces the band gap but also changes the n‐type character of pure WS2 monolayer to the p‐type character. Hence, it may be useful for channel material in field effect transistors (FETs). Moreover, the optical studies reveal that the WS2 monolayer shows a significantly good optical response. However, a small ultraviolet shift is observed in the optical response of the doped case compared to the pristine WS2 monolayer. This study suggests that the WS2 monolayer can be a possible optical material for optoelectronic applications, and it can also be a replacement of MoS2‐based future electronics and optoelectronics.
A discovery‐based undergraduate laboratory exercise to investigate the effect of potential endocrine disruptors on sex hormones using human cell culture
Authors: Kuzmanov Aleksandra , Zwiesler‐Vollick Julie
Published: July 2022

In this laboratory exercise, students have an opportunity to evaluate the potential endocrine disrupting abilities of environmental chemicals of their choice using human cell culture. Over the course of 9 weeks, students learn how to aseptically handle and manipulate cells, perform and analyze a cytotoxicity assay and an enzyme‐linked immunosorbent assay. Following completion of the module, the majority of students reported large or very large gains not only in laboratory performance, but also in understanding of the scientific literature and research process, as well as scientific communication skills. The student survey results imply that this authentic laboratory experience improves students' scientific literacy and prepares them for future careers in science.
Quantitative profiling of differentially expressed oxylipins in ADSCs under proinflammatory cytokine stimulation
Authors: Shen Zhengze , Wang Dan , Yu Chaoqun , Peng Yongbo , Cheng Lifang , Zhang Yuan
Published: July 2022

Mesenchymal stem cells (MSCs) have been proved to have anti‐inflammatory capabilities, but the mechanisms are still under investigation. Recently, oxylipins have been identified as being related to the immuno‐regulation function of MSCs, but the MSC‐derived oxylipins, especially under the stimulation of versatile pro‐inflammatory cytokines, have never been comprehensively analyzed. In the present research, a UPLC–MS/MS method was employed to identify and quantify the oxylipin profiles of adipose‐derived mesenchymal stem cells (ADSCs) under cytokine stimulation (IL‐1β, TNF‐α, IFN‐𝛾 and TNF‐α + IFN‐𝛾). The differentially produced oxylipins between experimental groups were analyzed and compared. The elevated level of lipoxygenase‐15 (LOX‐15) mRNA was further verified by qRT‐PCR analysis. From the targeted 71 oxylipins, we detected and quantified 57 oxylipins, while 14 were not detected. Distinctive from other cytokines, ADSCs activated by the combination of IFN‐𝛾 and TNF‐α up‐regulated LOX‐15 products 7‐HDHA and 15‐HEPE, which were metabolized from docosahexaenoic acid (DHA) and eicosapentaenoic acid, respectively, and involved in the pro‐resolution phase of inflammation. The results reported here make a first step towards a comprehensive characterization of MSC‐derived oxylipins under differential proinflammatory cytokine stimulation. The findings may lay a fundamental foundation for MSC‐based therapies and further determine ways to optimize the therapeutic potential of MSCs.
Bioanalytical assay for the quantification of the tyrosine kinase inhibitor EAI045 and its major metabolite PIA in mouse plasma and tissue homogenates using liquid chromatography–tandem mass spectrometry
Authors: Susam M. Merve , Wang Jing , Schinkel Alfred H. , Beijnen Jos H. , Sparidans Rolf W.
Published: July 2022

EAI045 is a tyrosine kinase inhibitor (TKI) that targets the mutant epidermal growth factor receptor (EGFR). It was developed to control resistance to available EGFR TKIs. In this study, a major metabolite of EAI045, (5‐fluoro‐2‐hydroxyphenyl)(1‐oxo‐1,3‐dihydro‐2H‐isoindol‐2‐yl)acetic acid (PIA), was discovered as a hydrolysis product of the parent drug. A validated assay for both analytes in mouse plasma and tissue homogenates from brain, kidney, liver, lung, spleen, and small intestine with content was set up using LC–MS/MS. Samples were prepared by protein precipitation with acetonitrile and with PLX4720 as internal standard. Separation was performed on a bridged ethylene hybrid C18 column by gradient elution with 0.1% v/v formic acid and methanol. Using positive electrospray, detection was performed in selected reaction monitoring mode. A linear calibration range of 2–2,000 ng/ml was used and validated for both analytes. Precision values ranged between 2.0 and 7.5% for EAI045 and between 2.2 and 12.1% for the metabolite, and accuracy values were between 91.1 and 107.6% for EAI045 and between 87.6 and 100.6% for the metabolite. Both analytes were sufficiently stable under the relevant analytical conditions. Finally, the assay was applied to analyze mouse plasma and tissue levels in a pharmacokinetic study in FVB/NRj wild‐type female mice treated with oral EAI045.
Treatment of Obese Zebrafish with Saringosterol Acetate through AMP Activated Protein Kinase Pathway
Authors: Zhou Dong‐Yue , Fu Yun‐Hua , Li Fang‐Tong , Yang Di , Wei Li‐Na , Yue Hao , Dai Yu‐Lin , Jeon You‐Jin
Published: July 2022

Object: Edible Brown Seaweed Sargassum fusiforme (Harvey) Setchell, 1931 abbreviated asSargassum fusiformewas used for folk medical therapy in East Asia countries over five hundred years. Saringosterol acetate (SA) was isolated fromS. fusiformein our previous study and indicated various effects. However, anti‐obesity activity of SA and its mechanism still unknown.Method: The inhibitory effect of SA, isolated fromS. fusiforme, on adipogenesis in 3T3‐L1 adipocytes was investigatedin vitroand in zebrafish model. Cell toxicity, differentiation, signaling pathway, and lipid accumulation of SA treated 3T3‐L1 adipocytes were determined. The body weight and triglyceride content of diet‐induced obese (DIO) adult male zebrafish were measured from 12 to 17 weeks after fertilization.Result: SA attenuated the differentiation of cells and reduced lipid accumulation, and triglyceride content in the 3T3‐L1 adipocytes. During the differentiation of adipocytes, SA suppressed fat accumulation and decreased the expression of signal factors responsible for adipogenesis. In SA‐treated adipocytes, while fatty acid synthetase was downregulated, AMP‐activated protein kinase (AMPK) was upregulated. Furthermore, SA suppressed body weight and triglyceride content in DIO zebrafish.Conclusion: SA is a potential therapeutic agent in the management of metabolic disorders, such as obesity.
Isolation, Characterization of Bamboo Leaf Flavonoids by Size Exclusion Chromatography and Their Antioxidant Properties
Authors: Ye Shuhuan , Pan Fupeng , Yao Linna , Fang Hailing , Cheng Yaqian , Zhang Zixuan , Chen Yongjian , Zhang Ailian
Published: July 2022

The utilization of bamboo industry exhibits varied but still needs to be improved. Bamboo leaf flavonoid (BLF) is an important resource of bamboo which has become a research focus. However, the isolation and purification techniques of four flavonoid carbon glycosides (orientin, isoorientin, vitexin, and isovitexin) from BLF were still confronted with difficulties due to their complex and similar structures, which obstructed the development of bamboo utilization. In this article, a purification technology of four flavonoid carbon glycosides from BLF by Sephadex LH‐20 was improved. The results were evaluated by HPLC and pharmacological activity. Specifically, the eluent, flow rate, and loading amount were investigated, respectively. According to the results, the eluent would dominate the isolation effect among three factors. High concentration of isoorientin and four flavonoid carbon glycosides would be obtained under the optimized condition (The eluent was 70 % methanol, the loading amount was 1.5 g, and the flow rate was 0.5 mL/min). Meanwhile, the link between flavonoid carbon glycosides content and their antioxidant activity in vitro was also revealed. Overall, the results suggested that BLF may serve as potential functional food additives and medicine.
The Synergetic Effect of Support‐oxygen Groups and Pt Particle Size in the Oxidation of α‐D‐glucose: A Proximity Effect in Adsorption
Authors: Führer Marlene , van Haasterecht Tomas , Masoud Nazila , Barrett Dean H. , Verhoeven Tiny , Hensen Emiel , Tromp Moniek , Rodella Cristiane B. , Bitter Harry
Published: July 2022

The influence of the support‐oxygen groups and Pt particle size on the catalytic performance of Pt/AC for the aerobic oxidation of α‐D‐glucose to gluconic acid (glycolate) was studied. Surface‐oxygen groups were introduced by treating the activated carbon support with diluted HNO3 without significantly affecting the support porosity. The platinum particle size could be decreased on both the treated and untreated support by adding an additional calcination step to the synthesis. The presence of oxygen‐containing groups is shown to be highly beneficial (∼4 fold increase in the turnover frequency) only for the smallest Pt particle size (1.8–2.5 nm, determined by TEM). For the catalyst with the larger Pt size (3.4–3.6 nm), the presence of additional oxygen‐contacting groups does not significantly enhance the activity. Since the size of the smaller Pt particles is close to the product/substrate molecular diameter (glucose/gluconic acid, ∼0.9 nm) the observed effect can be attributed to the effective repulsion by the negatively charged oxygen groups in close proximity to the glycolate reaction product. The increase in activity originates from the resulting enhanced desorption of glycolate by alleviating the product inhibition presence due to the strong interaction of glycolate with Pt.
Hyperkubisches Glas – Dalís »Vidriera Hipercúbica« neu interpretiert
Authors: Fernández‐Serrano Martino Peña , Wirfler Katja , López Sebastián Andrés , Reißaus Henrik , Weimar Thorsten
Published: July 2022

Das »Vidriera Hipercubica« ist als kinetisches Artefakt entwickelt, das eine Änderung des Zustands durch Faltung beziehungsweise Entfaltung ermöglicht. Das Konzept basiert auf dem Entwurf des spanischen Architekten Emilio Pérez Piñero für Salvador Dalí aus dem Jahr 1971 für einen kinetischen Raumabschluss zwischen ehemaligem Bühnen‐ und Zuschauerbereich des alten Theaters von Figueras, das zum Theater‐Museum Dalí umgebaut werden soll. Mit der Integration der Bewegung als vierte Dimension in der Architektur thematisiert das »Vidriera Hipercúbica« einen Ansatz in der Kunst des 20. Jahrhunderts analog zu der Zeit in der Physik. Gemeinsam mit Studierenden im Masterstudiengang Architektur an der Universität Siegen wird das Prinzip der originalen Konstruktion analysiert und mit digitalen Fertigungstechniken in die heutige Zeit als hyperkubisches Glas transferiert.

Hypercubic Glass – Dalís »Vidriera Hipercúbica« new interpreted. The »Vidriera Hipercúbica« is developed as a kinetic artefact that can change its state through folding and unfolding and is, thus, permanently in motion. The concept is based on the design by the Spanish architect Emilio Pérez Piñero for Salvador Dalí from 1971 for a kinetic room closure between the former stage and the audience area of the old theatre in Figueras, which is to be reformed into the Dalí Theatre‐Museum. With the integration of movement as the 4th dimension in architecture, the »Vidriera Hipercúbica« thematises an approach in 20th century art, analogous to the time in physics. Together with students of the Master's course of architecture at Universität Siegen, the design principle of the original construction is analysed and translated into the present by using digital production techniques.
Glas als Druckelement | Eine nachhaltige Lösung
Authors: Fadai Alireza , Weißenböck Lukas , Stephan Daniel
Published: July 2022

Im Rahmen der aktuellen Forschungsprojekte befassen sich die Autoren mit der ressourceneffizienten Optimierung von Tragelementen im mehrgeschossigen Hochbau. Die nachhaltige Architektur reagiert auf den umweltpolitischen Wandel und beschäftigt sich vermehrt mit den Baustoffen Holz, Stahl und Glas. In dem Beitrag soll die Signifikanz von Glas als Tragstruktur verdeutlicht werden. Anhand einer durchgeführten Studie für entwickelte Glas‐Hybridelemente konnten ein effizienter Einsatz ermittelt und eine materialgerechte Anwendung ermöglicht werden. Zur Verdeutlichung werden außerdem einige innovative Projekte und Forschungsarbeiten zu druckbeanspruchtem Glas vorgestellt. Mit einer ökologischen Bewertung und Gegenüberstellung der Stützelemente mit den konventionellen Ausführungen in Stahl‐, Stahlbeton‐ und Holzbauweise wird das Potenzial solcher Konstruktionen weiter belegt.

Glass as a compression member | A sustainable solution. As a part of the current research projects, the authors deal with the resource‐efficient optimization of load‐bearing elements in multi‐story building construction. Sustainable architecture reacts to changes in environmental policy and deals increasingly with the building materials timber, steel and glass. The aim of the paper is to clarify the significance of glass as a supporting structure. On the basis of a study carried out for developed glass hybrid elements, an efficient use was determined and an application appropriate to the material made possible. Some innovative projects and research work on pressure‐stressed glass are also presented. With an ecological assessment and comparison of the supporting elements with the conventional designs in steel, reinforced concrete and timber construction, the potential of such structures is further proven.
Analyse des Hagelwiderstandes von Gewächshaushüllen
Authors: Neugebauer Jürgen , Kneringer Georg Peter
Published: July 2022

Es wird aufgrund des Klimawandels in Zukunft vermehrt zu extremen Unwettersituationen, wie Sturm, Starkregenereignissen in Kombination mit Hagel, und den damit verbundenen Schäden in verschiedenen baulichen Bereichen unseres Lebens wie zum Beispiel bei Hüllen von Gewächshäusern durch Hagelschlag kommen. Aus diesem Grund ist es wichtig, sich mit den Themen beginnend von der Entstehung des Hagels bis zu den durch Hagelschlag hervorgerufenen Schäden zu beschäftigen. Durch geeignete Prüfeinrichtungen können die so genannten Hagelwiderstandsklassen im Labor ermittelt werden. Diese Bestimmung von den Hagelwiderstandsklassen wurde im Labor für unterschiedliche Hüllenmaterialien aus Kunststoff und Glas mittels geeignetem Versuchsaufbau durchgeführt.

Analysis of the hail resistance of greenhouse envelopes. Due to climate change, there will be more extreme storms in the future, such as storms, heavy rain events in combination with hail, and the associated damage in various structural areas of our life such as the envelopes of greenhouses from hail. For this reason, it is important to deal with the topics from the origin of the hail to the damage caused by hailstorms. The so‐called hail resistance classes can be determined in the laboratory using suitable testing equipment. This determination of the hail resistance classes was carried out in the laboratory for different cover materials made of plastic and glass using a suitable test set‐up.
Strukturelle Holz‐Glas‐Klebungen unter Kurz‐ und Langzeitbeanspruchung
Authors: Fecht Simon , Kaufmann Marvin , Vallée Till
Published: July 2022

Mit den hier vorgestellten Ergebnissen an geklebten Holz‐Glas‐Proben aus Experimenten unter Kurz‐ und Langzeitbeanspruchung mit vielen Parametern (Holzsorte, Klebstoff, Temperaturen und Luftfeuchtigkeit) konnten neue Erkenntnisse gewonnen werden. Bei Zug‐ und Durckscherproben hat der Klebstoff den größeren Einfluss auf die Festigkeit. Die Temperatur bei 1K‐PU, Silanen und Acrylaten hat bis 60 °C einen signifikanten Einfluss auf die Festigkeit, bei 2K‐Epoxiden bis 80 °C keinen. In Verbundversuchen unter dauerhafter zyklischer Klimalagerung wurde deutlich, dass durch das Holzquellen Zugspannungen an der Glasaußenseite auftreten. Dies stellt eine ungünstige Belastungssituation für großflächig verklebte Glasscheiben dar, die bei Klebstoffen mit hoher Steifigkeit zu Rissen im Glas führen.

Structural wood‐glass‐bonds under short‐ and long‐term loading. The results presented here on bonded wood‐glass specimens from experiments under short‐ and long‐term stress with many parameters (wood type, adhesive, temperatures, and humidity) provided new insights. In tensile and compression tests, the adhesive has the greater influence on the strength. The temperature has a significant influence on the strength of 1K PU, silanes and acrylates up to 60 °C, and none up to 80 °C for 2K epoxies. In composite tests under permanent cyclic climate storage, it became clear that tensile stresses occur on the outside of the glass due to wood swelling. This is an unfavourable load situation for glass panes bonded over a large area, which leads to cracks in the glass in the case of adhesives with high stiffness.
Einfluss der Zwischenschicht auf das Bruchverhalten von Verbundsicherheitsglas
Authors: Weis Jasmin , Siebert Geralt
Published: July 2022

Ein aktuelles Forschungsthema im Bereich des konstruktiven Glasbaus ist der rechnerische Nachweis der Resttragfähigkeit von Verbundsicherheitsglas (VSG) aus Einscheibensicherheitsglas (ESG). Zur Beschreibung des Resttragverhaltens ist neben der reinen Zwischenschicht auch der Verbund sowie der Kontakt zwischen den Glasbruchstücken zu charakterisieren. Somit ist es im Fall von gebrochenem VSG aus ESG notwendig, das Bruchbild zu erfassen. Bisherige Untersuchungen fanden dahingehend an einzelnen, monolithischen ESG (Mono‐Scheiben) statt. In dieser Arbeit wird der Einfluss der Zwischenschicht auf das Bruchverhalten und das dadurch bedingte Bruchbild untersucht und mithilfe modernster Messgeräte wie Zeiss Scanner, Highspeed‐Kamera und CulletScanner erfasst. Schließlich kann gezeigt werden, dass sich das Bruchverhalten eines ESG als Teil von VSG eklatant von dem einer Mono‐Scheibe unterscheidet.

Influence of the interlayer on the fracture behavior of laminated safety glass. A current research topic in the field of structural glass engineering is the computational design of the residual load‐bearing capacity of laminated safety glass made from fully tempered glass (FTG). To describe the residual load‐bearing behaviour besides the interlayer itself, the bond and the contact between the glass fragments must also be characterized. Thus, in the case of broken laminated safety glass made from FTG, it is necessary to determine the fracture pattern. Previous investigations have been carried out on mono‐panes. In this work, the influence of the interlayer on the fracture behaviour and the resulting fracture pattern is investigated for the first time and recorded using state‐of‐the‐art measuring equipment such as Zeiss scanners, high‐speed camera, and cullet scanner. Finally, it can be shown that the fracture behaviour of a laminated safety glass differs from that of a mono layer.
Komplexe Glaskonstruktionen im Projekt Morland Mixité Capitale in Paris
Authors: Fildhuth Thiemo , Oppe Matthias , Damon Pascal , Crossley Jeremy
Published: July 2022

Im Zuge des Umbaus der ehemaligen Präfektur von Paris am Boulevard Morland wird im 15. und 16. Obergeschoss ein vollständig verglaster, öffentlicher Bereich mit Gastronomie und einer kaleidoskopartigen Kunstinstallation (Arch. D. Chipperfield/Studio Other Spaces) neu geschaffen. Die Fassaden im 16. Obergeschoss bestehen aus zweiseitig horizontal gelagertem, Structural‐Glazing‐verklebtem Isolierglas mit variabler keramischer Bedruckung und reflektierender Beschichtung. Darüber sind die „Kaleidoskope” eingehängt, deren spiegelnde Glasschotten die Grenze zwischen innen und außen aufheben. Jedes der 32 Kaleidoskopmodule wird nach oben durch ein bombiertes Isolierglas abgeschlossen. Der vorliegende Beitrag behandelt die detaillierte Umsetzung dieser Glaskonstruktionen.

Complex glass construction within the project Morland Mixité Capitale in Paris. The renovation and conversion of the former prefecture of the city of Paris at the Boulevard Morland (Arch.: D. Chipperfield) comprises the construction of a new two‐storey, fully glazed, public space on top of the existing building. Intended for gastronomical use, it comprises a kaleidoscope‐like glass art installation designed by Studio Other Spaces. The envelope of the 16th floor consists of two‐side supported, large SG‐bonded IGUs with variable ceramic frit and reflective mirror‐coating. The ceiling above is assembled from “kaleidoscope”‐modules comprising suspended mirror‐glass sheets that confusingly blur the boundaries between inside and the outside. Each of the 32 kaleidoscope‐boxes is covered by a double‐curved insulating glass unit. The present contribution deciphers the complex construction design and realization process of these glass structures.
Return on investment and water savings of add‐on irrigation sensors for bermudagrass lawn irrigation in Northwest Arkansas
Authors: Sandor Daniel , Karcher Douglas , Richardson Michael
Published: July 2022

Homeowners with automated sprinkler systems water lawns frequently and may be unaware of the volume of water applied in their irrigation programs. Rain sensors (RS) and soil moisture sensors (SMS) may reduce watering by permitting scheduled irrigation to occur relative to recent rainfall or current soil moisture status and are available as add‐on technologies for residential sprinkler systems. As RS and SMS may positively impact irrigation scheduling, incorporating them into existing sprinkler systems may reduce water use and provide a return on investment (ROI), without compromising turfgrass quality. The objectives of this research were to determine the water savings of add‐on RS and SMS, estimate their ROI, and evaluate their impact on bermudagrass [Cynodon dactylon (L.) Pers.] lawn quality over three summers in Northwest Arkansas. An irrigation schedule without a sensor (control) was programmed to apply 0.5 inches of water twice a week for 17 wk. Water usage and turfgrass quality under the control were compared with two RS and two SMS, following the same program. During the 3‐yr study, RS and SMS reduced annual water use by an average of 22.1 and 66.2%, respectively. All treatments exhibited similar turfgrass quality and remained above the minimum level of acceptable quality. Under these experimental conditions, the average ROI for RS and SMS was estimated to be $87 and $200, respectively, within the first year of installation. Regional best management practices for watering bermudagrass lawns should include the incorporation of RS and SMS to reduce irrigation, maintain turfgrass quality, and save money.
Efficient and Selective Electroreduction of CO2 to HCOOH over Bismuth‐Based Bromide Perovskites in Acidic Electrolytes
Authors: Wang Yan , Wang Chun , Wei Yi , Wei Fang , Kong Lichun , Feng Jiuju , Lu Ji‐Qing , Zhou Xiaocheng , Yang Fa
Published: July 2022

Metal halide perovskites, primarily used as optoelectronic devices, have not been applied for electrochemical conversion due to their insufficient stability in moisture. Herein, two bismuth‐based perovskites are introduced as novel electrocatalysts to convert CO2 into HCOOH in aqueous acidic media (pH 2.5), exhibiting a high Faradaic efficiency for HCOOH of >80 % in a wide potential range from −0.75 to −1.25 V. Their structural evolution against water was dynamically monitored by in situ spectra. Theoretical calculations further reveal that the formation of intermediate OCHO* on bismuth sites of Cs3Bi2Br9(111) play a pivotal role toward HCOOH production, which has a lower energy barrier than that on Cs2AgBiBr6(001) surfaces. Significantly, CO2 reacts with protons instead of water which can enhance CO2 reduction rate and suppress hydrogen evolution by avoiding carbonate formation in acidic electrolytes. This work paves the way for the extensive investigation of halide perovskites in aqueous systems.
CO2 Laser‐Induced Graphene with an Appropriate Oxygen Species as an Efficient Electrocatalyst for Hydrogen Peroxide Synthesis
Authors: Fan Mengmeng , Xu Jing , Wang Yan , Yuan Qixin , Zhao Yuying , Wang Zeming , Jiang Jianchun
Published: July 2022

Oxygen species functionalized graphene (O−G) is an effective electrocatalyst for electrochemically synthesizing hydrogen peroxide (H2O2) by a 2 e− oxygen reduction reaction (ORR). The type of oxygen species and degree of carbon crystallinity in O−G are two key factors for the high catalytic performance of the 2 e− ORR. However, the general preparing method of O−G by the precursor of graphite has the disadvantages of consuming massive strong oxidant and washing water. Herein, the biomass‐based graphene with tunable oxygen species is rapidly fabricated by a CO2 laser. In a flow cell setup, the laser‐induced graphene (LIG) with abundant active oxygen species and graphene structure shows high catalytic performance including high Faraday efficiency (over 78 %) and high mass activity (814 mmolgcatalyst−1 h−1), superior to most of the reported carbon‐based electrocatalysts. Density function theory demonstrates the meta‐C atoms at nearby C−O, O−C=O species are the key catalytic sites. Therefore, we develop one facile method to rapidly convert biomass to graphene electrocatalyst used for H2O2 synthesis.
An efficient sparse stiffness matrix vector multiplication using compressed sparse row storage format on AMD GPU
Authors: Xing Longyue , Wang Zhaoshun , Ding Zhezhao , Chu Genshen , Dong Lingyu , Xiao Nan
Published: July 2022

The performance of sparse stiffness matrix‐vector multiplication is essential for large‐scale structural mechanics numerical simulation. Compressed sparse row (CSR) is the most common format for storing sparse stiffness matrices. However, the high sparsity of the sparse stiffness matrix makes the number of nonzero elements per row very small. Therefore, the CSR‐scalar algorithm, light algorithm, and HOLA algorithm in the calculation will cause some threads in the GPU to be in idle state, which will not only affect the computing performance but also waste computing resources. In this article, a new algorithm, CSR‐vector row, is proposed for fine‐grained computing optimization based on the AMD GPU architecture on heterogeneous supercomputers. This algorithm can set a vector to calculate a row based on the number of nonzero elements of the stiffness matrix. CSR‐vector row has efficient reduce operations, deep memory access optimization, better memory access, and calculation overlapping kernel function configuration scheme. The access bandwidth of the algorithm on AMD GPU is more than 700 GB/s. Compared with CSR‐scalar algorithm, the parallel efficiency of CSR‐vector row is improved by 7.2 times. And floating‐point computing performance is 41%–95% higher than that of light algorithm and HOLA algorithm. In addition, CSR‐vector row is used to calculate the examples from CFD, electromagnetics, quantum chemistry, power network, and semiconductor process, the memory access bandwidth and double floating‐point performance are also improved compared with rocSPARSE‐CSR‐vector.
Approximate function memoization
Authors: Arundhati Priya , Jena Sisir Kumar , Pani Santosh Kumar
Published: July 2022

Function memoization is an optimization technique that reduces a function call overhead when the same input appears again. A table that stores the previous result is searched and used to skip the repeated computation. This way, it increases the performance of the function call. In this article, we propose a software approach of function memoization to improve computing efficiency by bypassing the execution of the function implemented using approximate computing techniques. Searching overhead is a primary concern in any memoization technique proposed so far. In traditional function memoization, the input arguments are first searched in the look‐up table (LUT) for an exact match, and the corresponding result is extracted for further use. But, in this article, a decision‐making rule is proposed to help us decide whether to search the LUT or go for the actual computation. This decision‐making model is implemented through Bloom filter and Cantor's pairing function. Because Bloom filter sometimes produces false‐positive results, we suggest a simple approximation technique that searches the LUT for an approximate match rather than an exact match. The proposed model also contains a bypass algorithm implemented through C++ code that identifies the trivial computations from the input argument of the candidate function. By this, we can avoid the actual calculation and generate the result directly. Here, trivial computation identifies one or more input arguments that are either 0 or . To analyze the effectiveness of our proposed technique, we conducted several experiments using the benchmarks from the AxBench suite. We found that our result outperforms some of the methods proposed so far in terms of energy consumption and quality of results, particularly in image processing applications.
A hybrid five‐level inverter configuration with improved reliability and reduced number of components
Authors: Saketi Sai Krishna , Chaturvedi Pradyumn , Yadeo Dharmendra , Atkar Dipesh
Published: July 2022

The provision of significant redundant states in multilevel inverters (MLIs) aids in fault‐tolerant operation. However, this deals with several components, leading to low reliability. This paper proposes a new fault‐tolerant five‐level MLI with reduced component count, which can withstand both single‐ and multiple‐switch faults. The reduced carrier‐based level shifted sinusoidal pulse width modulation (RCLSPWM) strategy is developed to generate control signals for the switches. The employed control scheme automatically balances the voltage across the capacitor. The logic gate expressions for generating gate pulses of the switches under normal and fault‐tolerant operating modes are described in detail. The comparative analysis is carried out to demonstrate the effectiveness of the proposed topology over other existing similar topologies. The performance of the laboratory prototype developed is found satisfactory as compared to other existing topologies under various operating conditions.
Outage analysis of cooperative NOMA system with imperfect successive interference cancellation and channel state information over Rayleigh fading channel
Authors: K Srinivasarao , Maruthu Surendar
Published: July 2022

Cooperative communication is a significant technology for fifth generation (5G) and beyond wireless communication to improve the quality of service (QoS) in massive networks. In addition, it serves as a promising candidate along with non‐orthogonal multiple access (NOMA) scheme to increase the spectral efficiency. Conventionally, cooperative‐NOMA (C‐NOMA) systems are analysed by assuming perfect successive interference cancellation (SIC) and imperfect SIC (I‐SIC) over Rayleigh, Rican,
Hoyt fading channels, and so on. In this paper, near–far relay (NFR) C‐NOMA system is analysed aiding perfect SIC, perfect channel state information (CSI), imperfect (I‐CSI) and (I‐SIC) over Rayleigh fading channel. Initially, we derive analytical expressions of outage probability (OP) by considering I‐SIC and I‐CSI for NFR‐C‐NOMA system. The accuracy of analytical results is verified through Monte Carlo (MC) simulations. Interpretation of the results conveys that I‐CSI and I‐SIC have a substantial impact on OP in NFR‐C‐NOMA scheme and existing schemes. Later, we examined impact on OP in NFR‐C‐NOMA by varying relay position, target rate of users and jointly considering the I‐SIC, I‐CSI. Further, it is also observed that the NFR‐C‐NOMA scheme shows better outage performance than state‐of‐the‐art schemes.