bluuebunny/crossref_metadata_2025_split huggingface dataset:
Redox‐gesteuertes Entkleben von Muschel‐inspirierten Haftklebstoffen: Effizienzsteigerung durch funktionales Design
Authors: Neubert Tilmann J. , Walter Keven , Schröter Carolin , Guglielmotti Victoria , Hinrichs Karsten , Reinicke Stefan , Taden Andreas , Balasubramanian Kannan , Börner Hans G. 
Published: July 2024

AbstractAuf dem Weg zur Kreislaufwirtschaft ermöglichen abschaltbare Haftklebstoffe (engl. pressure sensitive adhesives, PSA) Zugang zu Wiederverwertbarkeitsstrategien in der Mikroelektronik. Zwei PSAs wurden aus einem tetravalenten Thiol‐Sternpolyester synthetisiert, der Thiol‐Catechol‐Verknüpfungen (thiol‐catechol‐connectivity, TCC) mit dem biobasierten DiDopa‐Bischinon (BY*Q) oder dem fossilbasierten Bischinon A (BQA) bildet. Die PSAs ermöglichen das Entkleben durch Oxidation der TCC‐Catechole zu Chinonen. Die Ablösungseffizienz hängt von den Interaktionsmoden ab, die aus den unterschiedlichen chemischen Strukturen der beiden TCC‐Motive folgen. BY*Q‐TCC‐PSA zeigt beim Entkleben einen außergewöhnlichen Verlust von 99 % seiner ursprünglichen Scherfestigkeit von ca. 2 MPa in Glas‐auf‐Glas‐Verklebungen. Für BQA‐TCC‐PSA wurde ein Verlust der Scherfestigkeit von nur ca. 60 % festgestellt, unabhängig vom ursprünglichen Wert, der bis auf ca. 7 MPa eingestellt werden konnte. Die Effizienz der Ablösung von BY*Q‐TCC‐PSA nach der TCC‐Oxidation konnte mit dem Verlust synergetischer Wechselwirkungen in Verbindung gebracht werden. Dabei verändern sich die Eigenschaften des Bulk‐Klebstoffs weniger stark als im nur auf Catecholen basierenden BQA‐Analogon.
MnO2@Al‐BDC nanocomposite as adsorbent of remarkable high efficiency toward iron remediation from wastewaters
Authors: Said Mohamed I. , Sayed Marwa , Aly Aref A. M. , Atef Muhammad 
Published: July 2024

Global environmental problems, especially those related to water contamination brought on by rapid industrialization and economic growth, are among the most dangerous threats facing humanity today. In this research work, Al3+ based metal–organic framework with 1,4‐benzenedicarboxylic acid (H2BDC) linker has been synthesized by a simple and economic coprecipitation method. The obtained Al‐BDC MOF was utilized as an adsorbent for sequestering iron from wastewater, but only 54.0% of iron concentration was eliminated after 120 min. To boost the removal efficiency, modification of the Al‐BDC MOF was carried out. MnO2@Al‐BDC nanocomposite was prepared and applied as a nanoadsorbent for iron remediation from water. The adsorption capability of Al‐BDC MOF was greatly enhanced by facile modification. The adsorption efficiency reached 97.0% using 35.0 mg of the nanocomposite after 120 min compared to 54.0% iron removal using the un‐modified MOF. The effect of pH of the medium was then studied using MnO2@Al‐BDC nanocomposite. The best elimination efficacy of iron was accomplished at pH ~ 2.2. The adsorption of iron on the surface of MnO2@Al‐BDC nanocomposite attains 97.0% (120 min) using a 35.0 mg dose of adsorbent and reaches 98.7% utilizing a 50.0 mg dose of adsorbent. In contrast, at pH = 9.2, the removal efficiency drops to 90.0% (after 120 min, 35.0 mg adsorbent). The adsorption capability was examined also using a variety of iron concentrations, i.e., 2.5, 5.0, and 7.5 mg/L where the adsorption efficiency dropped notably upon increasing the concentration. It dropped from 96.3% to 87.0% using 35.0 mg of MnO2@Al‐BDC nanocomposite at 90 min. The newly developed adsorbent showed a pronounced efficiency for Fe3+ removal against real samples collected from different water sources. Ultimately, this research introduces a novel MnO2@Al‐BDC nanocomposite, synthesized through a simple and economical coprecipitation method, to address water contamination by iron. The innovation lies in the significant enhancement of iron elimination efficiency, from 54.0% with unmodified Al‐BDC MOF to 97.0% with the MnO2@Al‐BDC nanocomposite.
An effective CaenorhabditiselegansCRISPR training module for high school and undergraduate summer research experiences in molecular biology
Authors: Herrera Sandoval Carmen , Borchers Christopher , Aoki Scott T 
Published: July 2024

AbstractEngaging in research experiences as a high school or undergraduate student interested in science, technology, engineering, and mathematics (STEM) is pivotal for their academic and professional development. A structured teaching framework can help cultivate a student's curiosity and passion for learning and research. In this study, an eight‐week training program was created to encompass fundamental molecular biology principles and hands‐on laboratory activities. This curriculum focuses on using clustered regularly interspaced short palindromic repeats (CRISPR) gene editing in the Caenorhabditis elegans model organism. Through pre‐ and post‐program assessments, enhancements in students' molecular biology proficiency and enthusiasm for scientific exploration were observed. Overall, this training module demonstrated its accessibility and ability to engage inexperienced students in molecular biology and gene editing methodologies.
Influence of phosphates on phase formation in alkali‐activated MgO‐Al2O3‐SiO2‐P2O5 cements
Authors: Reed Titus , Mauro John C. , Gevaudan Juan Pablo 
Published: July 2024

AbstractThe impact of phosphates on phase formation in low Ca alkali‐activated materials (AAMs) is investigated using a polymer‐assisted sol‐gel process to fabricate MgO‐Al2O3‐SiO2‐P2O5 cement precursors covering a broad range of compositions activated with sodium hydroxide. X‐ray diffraction and magic angle spinning‐nuclear magnetic resonance are used to examine the crystalline and amorphous phases that form over 470 days of curing (35°C, 90% relative humidity). The results confirm that Al is preferentially incorporated into hydrotalcite‐like layered double hydroxides (LDH) over zeolites. Zeolites form when more Al is present than can be incorporated into the LDH. Little evidence of phosphate incorporation into aluminosilicate networks (such as zeolites or disordered aluminosilicate hydrate) was observed. The phosphates present in the precursor favor reaction with sodium to form water‐soluble sodium phosphate phases. In most cases, the remainder of the phosphates become adsorbed to the surface of other phases and are not intercalated into the LDH, though at high phosphate concentrations (26.6 wt. % P2O5) and extended curing times (470 days), phosphates are observed to intercalate into LDH phases. These results provide preliminary evidence that phosphates are compatible with low Ca AAMs, which is consequential as there is a growing interest in both the use of AAM and phosphate‐based corrosion inhibiter in steel‐reinforced concrete.
Comparative structural study on axonemal and cytoplasmic dyneins
Authors: Zimmermann Noemi , Ishikawa Takashi 
Published: July 2024

AbstractAxonemal dyneins are the driving force of motile cilia, while cytoplasmic dyneins play an essential role in minus‐end oriented intracellular transport. Their molecular structure is indispensable for an understanding of the molecular mechanism of ciliary beating and cargo transport. After some initial structural analysis of cytoplasmic dyneins, which are easier to manipulate with genetic engineering, using X‐ray crystallography and single‐particle cryo‐electron microscopy, a number of atomic and pseudo‐atomic structural analyses of axonemal dyneins have been published. Currently, several structures of dyneins in the post‐power stroke conformation as well as a few structures in the pre‐power stroke conformation are available. It will be worth systematically comparing conformations of dynein motor proteins from different sources and at different states, to understand their role in biological function. In this review, we will overview published high‐ and intermediate‐resolution structures of cytoplasmic and axonemal dyneins, compare the high‐resolution structures of their core motor domains and overall tail conformations at various nucleotide states, and discuss their force generation mechanism.
Spider Silk‐Inspired Hyaluronic Acid‐Based Hydrogels with Superior Self‐Healing Capability and Enhanced Strength
Authors: Yang Kaidan , Zhou Ding , Wang Yachao , Chen Ruina , Dong Qi , Xiao Pu , Zhou Yingshan , Zhang Jing 
Published: July 2024

AbstractHyaluronic acid hydrogels are promising materials for diverse applications, yet their potential is hampered by limitations such as low self‐healing efficiency and insufficient mechanical strength. Inspired by the heterogeneous structures of spider silk, we introduce a novel dual dynamically crosslinked network hydrogel. This hydrogel comprises an acylhydrazone‐crosslinked network, utilizing aldehyde hyaluronic acid (AHA) and 3,3′‐dithiobis (propionohydrazide) (DTP) as a first network, and a secondary network formed by hydrogen bonds‐crosslinked network between tannic acid (TA) and silk fibroin (SF) with β‐sheet formation. The hydrogel exhibits exceptional self‐healing ability due to the dynamic and reversible nature of Schiff base bonds, disulfide bonds, and hydrogen bonds, achieving complete healing within 5 minutes. Additionally, the spider silk‐inspired heterogeneous structures enhance mechanical properties. Furthermore, the incorporation of TA provides enhances adhesion, as well as remarkable antibacterial and antioxidant properties. This innovative hyaluronic acid‐based hydrogel, inspired by spider silk, offers a promising avenue to fortify both the mechanical strength and self‐healing capabilities of hydrogels, thus expanding opportunities for applications in tissue engineering and biomedicine.
Recent Progress on the Involvement of Formaldehyde in the Methanol‐To‐Hydrocarbons Reaction
Authors: Luo Jinsong , Xiao Tianci , Liu Chengyuan , Pan Yang 
Published: July 2024

AbstractThis review summarized the recent research progress on the crucial role of formaldehyde during the methanol‐to‐hydrocarbons (MTH) reaction. As a reaction intermediate, formaldehyde participates in the formation of carbon–carbon, the establish of dual‐cycle, and the coking process of MTH reaction. Different techniques for formaldehyde detection in the study of MTH are also introduced.The conversion of methanol‐to‐hydrocarbons (MTH) over zeolite catalysts has been the subject of intense research since its discovery. Great effort has been devoted to the investigation of four key topics: the initiation of C−C bonds, the establishment of hydrocarbon pool (HCP), the adjustment of product selectivity, and the deactivation process of catalysts. Despite 50 years of study, some mechanisms remain controversial. However, an intermediate species, formaldehyde (HCHO), has recently garnered considerable attention for its influence on the entire MTH process. The discovery of HCHO and its significant role in the MTH process has been facilitated by the application of in situ analytical techniques, such as synchrotron radiation photoionization mass spectrometry (SR‐PIMS) and photoelectron photoion coincidence spectroscopy (PEPICO). It is now revealed that HCHO is involved in the initiation, propagation, and termination process of MTH reaction. Such mechanistic understanding of HCHO′s involvement has provided valuable insights for optimizing the MTH process.
The World Health Organisation Global Code of Practice and migration of health workers from Zimbabwe
Authors: Chikanda Abel 
Published: July 2024

AbstractThe migration of health workers remains one of the most pressing challenges facing many countries in the global South. This short communication seeks to reignite debate on the effectiveness of the World Health Organisation (WHO) Code as a tool for managing the migration of health workers from the South. While the WHO Code was somewhat effective in reducing the migration of health workers from countries such as Zimbabwe during the first five years of its implementation, demand for health workers in the UK after Brexit and the COVID‐19 pandemic has accelerated the rate of migration of health workers from countries facing critical shortages. Clearly, new solutions are needed that strike a balance between the right of health workers in the South to migrate and the right of citizens in the region to a stable supply of health workers.
Ultrastructure and distribution of antennal sensilla of parasitic wasp, Cotesia gregalis (Hymenoptera: Braconidae)
Authors: Liu Le , Wei Ke , Ren Zhe , Wang Xiaoyi 
Published: July 2024

AbstractCotesia gregalis Yang et Wei (Hymenoptera: Braconidae) is a gregarious koinobiont endoparasitic wasp attacking the larvae of fall webworm, Hyphantria cunea, an important invasive insect pest in China. To better understand the parasitic wasps' mating and parasitic behaviors, we examined the morphology of the antennae of adult C. gregalis, as well as the type, number, and distribution of antennal sensilla, via scanning electron microscopy. The antennae of female and male C. gregalis are filiform and comprise a scape, pedicel, and 16 flagellomeres. The female antennae are significantly shorter than those of male. A total of nine morphological types of antennal sensilla (mechanoreceptor and chemoreceptor) are presented in both sexes, including four mechanoreceptors (sensilla chaetica [two subtypes], sensilla trichodea and Böhm bristles); five chemoreceptors (sensilla basiconica [two subtypes], sensilla placodea, sensilla styloconica, and sensilla coelocapitula). There is no difference in the type and distribution of antennal sensilla between males and females, but the number and length of some antennal sensilla show sexual dimorphism. The functional morphology of the sensilla of C. gregalis is discussed by comparison with other parasitic wasps. These findings provide foundation for further research on the chemical communication and host localization mechanisms of C. gregalis.Research Highlights
The first report of morphology and distribution pattern of the antennal sensilla in C. gregalis is discussed.
A total of seven main types and nine antennal sensilla subtypes are observed in male and female C. gregalis.
The type and distribution of antennal sensilla in males and females are identical; however, the number and length of certain antennal sensilla show sexual dimorphism.
Winter entrainment drives the mixed layer supply of manganese in the Southern Ocean
Authors: Ramalepe Thapelo , Samanta Saumik , Cloete Ryan , Ryan‐Keogh Thomas J. , Roychoudhury Alakendra N. 
Published: July 2024

AbstractDespite the subnanomolar dissolved manganese concentrations that can co‐limit Southern Ocean primary production, their physical supply mechanisms during winter, for biological consumption in spring and summer have not yet been explored. During austral winter and spring 2019, two cruises were conducted in the Atlantic sector of the Southern Ocean, to determine the distribution and surface water supply mechanisms of dissolved manganese in the upper water column. The supply mechanisms were used to calculate the total flux of dissolved manganese to productive surface waters and were compared to biological consumption estimates. Mean dissolved manganese concentrations in the upper water column (< 500 m) during winter and spring were comparably low (≤ 0.34 nmol kg−1; p > 0.05), with seasonal mixed layer reservoir sizes averaging 65.21 ± 12.93 and 21.64 ± 19.32 μmol m−2, respectively. Winter entrainment contributed 89.33–99.99% (average 97.26% ± 5.28%) of the total dissolved manganese flux, while diapycnal diffusion contributed 0.52–10.58% (average 4.92% ± 5.14%), was identified as the dominant mechanisms for transporting dissolved manganese into the mixed layer in the subantarctic zone, polar frontal zone, and antarctic zone. Here, the winter physical supply rates were higher than the estimated consumption rates during spring, meeting phytoplankton biological demands. Whereas in the subtropical zone, the supply rates were lower than the consumption rates, indicating the presence of additional supply mechanisms such as coastal upwelling, which may help to meet the biological demands in this region.
Mode management in Bottom‐Up, Parity‐Time‐Symmetric Micro‐Cavity Lasers
Authors: Wong Wei Wen , Zhang Jihua , Garg Gaurang , Jagadish Chennupati , Tan Hark Hoe 
Published: July 2024

AbstractThe intrinsic non‐Hermiticity of photonic devices with tunable optical gain and loss makes them excellent platforms to explore and implement applications based on parity‐time symmetry, and a notable example is mode management in micro‐cavity lasers. Thus far, parity‐time‐symmetric lasers are fabricated via conventional top‐down etching processes, which are known to cause cavity sidewall roughness that is potentially detrimental to laser performance. Bottom‐up fabrication of parity‐time‐symmetric lasers, however, has seen limited success due to strict requirements on the uniformity of cavity morphology. Here, parity‐time‐symmetric lasing is demonstrated in coupled InP micro‐ring cavities grown directly by selective area epitaxy. With a facet engineering technique, ring laser cavities with a highly deterministic morphology are realized, enabling parity‐time‐symmetric laser designs. Furthermore, benefiting from the versatility and controllability of this bottom‐up process, lasing mode selectivity can be enhanced through coupling gap tuning and cavity shape engineering, leading to single‐mode lasing with a peak side mode suppression ratio exceeding 17 dB and a threefold single‐mode brightness enhancement compared to a single, uncoupled laser cavity. This work unlocks a lasing mode management strategy that is previously unavailable to bottom‐up laser cavities, which is a major step toward the realization of on‐chip, low‐loss, and single‐mode micro‐cavity lasers.
Analysis and numerical methods for nonlocal‐in‐time Allen‐Cahn equation
Authors: Li Hongwei , Yang Jiang , Zhang Wei 
Published: July 2024

AbstractIn this paper, we investigate the nonlocal‐in‐time Allen‐Cahn equation (NiTACE), which incorporates a nonlocal operator in time with a finite nonlocal memory. Our objective is to examine the well‐posedness of the NiTACE by establishing the maximal regularity for the nonlocal‐in‐time parabolic equations with fractional power kernels. Furthermore, we derive a uniform energy bound by leveraging the positive definite property of kernel functions. We also develop an energy‐stable time stepping scheme specifically designed for the NiTACE. Additionally, we analyze the discrete maximum principle and energy dissipation law, which hold significant importance for phase field models. To ensure convergence, we verify the asymptotic compatibility of the proposed stable scheme. Lastly, we provide several numerical examples to illustrate the accuracy and effectiveness of our method.
Moving into higher education: An examination of student mobility under the Independent Freshman Admission Program in China
Authors: Cui Can , Yu Chengyuan , Chen Nanxi , Deng Xinghua 
Published: July 2024

AbstractStudent mobility, as a significant component of population movements, shapes the distribution of intellectual individuals and reflects regional equity in access to higher education. In China, the National College Entrance Examination (Gaokao) traditionally governs university admissions through a province‐based quota scheme. In 2003, the Independent Freshman Admission Program (IFAP) was introduced to enhance flexibility and university autonomy in the admissions process, in which no quota is set for each province, breaking geographical constraints. However, the extent to which the IFAP has impacted student mobility remains largely unexplored. This study investigates the province‐to‐university migration patterns under different higher education admission schemes, revealing IFAP's preference for recruiting students from provinces with well‐developed basic education and a large student population. Furthermore, under the IFAP, students tend to flow to the top‐ranked universities and concentrate in favourable locations, such as First‐tier cities, while the quota allocation shows a more balanced distribution. These findings highlight the crucial role of policy in shaping student mobility, particularly within the context of strong institutional forces, and underscore the need to develop refined policies that balance equitable educational opportunities and regional equity.
Composite observer based finite time control for nonlinear systems subjecting to multiple disturbances
Authors: Zhang Huifeng , Wei Xinjiang , Li Xinqing 
Published: July 2024

AbstractComposite observer based finite time control of nonlinear systems in case of multiple disturbances is studied in this article, wherein the disturbances contain two parts, the first type is the harmonic disturbance with modeling errors, and all other disturbances are classified as the second type, known as lumped disturbances. To give estimation of the harmonic disturbance and the lumped disturbances, a disturbance observer (DO) and the extended state observer are constructed, respectively. On this basis, a finite‐time elegant anti‐disturbance controller is presented by combing DO‐based control, active disturbance rejection control, backstepping technique and the finite time command filter method. Eventually, it is proved that the design method put forward in this article is correct and feasible.
Design of zero‐sum game‐based H∞$$ {H}_{\infty } $$ optimal preview repetitive control systems with external disturbance and input delay
Authors: Liu Da , Lan Yong‐Hong 
Published: July 2024

AbstractIn this article, an optimal preview repetitive control (OPRC) scheme is proposed to deal with the disturbance attenuation problem for continuous‐time linear systems with external unknown disturbance and input delay. A general bounded gain is applied to the OPRC tracking control problem by introducing a function with discounted performance. First, an augmented system containing system state equation, tracking error dynamics, and modified repetitive control output equation is constructed, which is then transformed into a non‐delayed one by state transformation. Next, the OPRC controller is given and the game algebraic Riccati equation (GARE) is derived by transforming the tracking problem into a 2‐player zero‐sum game problem to give a Nash equilibrium solution of the associated min–max optimization problem. Besides, a value iteration (VI) algorithm is introduced to optimize the solution of continuous time GARE and ensure its convergence. Furthermore, the bounded‐input bounded‐output stability of the closed‐loop system is obtained by giving an upper bound on the discount factor. Finally, the numerical simulation example is provided to illustrate the effectiveness of the proposed method.
An updated review and perspective on efficient hydrogen generation via solar thermal water splitting
Authors: Tran Justin T. , Warren Kent J. , Wilson Steven A. , Muhich Christopher L. , Musgrave Charles B. , Weimer Alan W. 
Published: July 2024

AbstractSolar thermal water splitting (STWS) produces renewable (or green) hydrogen from water using concentrated sunlight. Because STWS utilizes energy from the entire solar spectrum to drive the reduction–oxidation (redox) reactions that split water, it can achieve high theoretical solar‐to‐hydrogen efficiencies. In a two‐step STWS process, a metal oxide that serves as a redox mediator is first heated with concentrated sunlight to high temperatures (T >1000°C) to reduce it and evolve oxygen. In the second step, the reduced material is exposed to steam to reoxidize it to its original oxidation state and produce hydrogen. Various aspects of this process are comprehensively reviewed in this work, including the reduction and oxidation chemistries of active materials considered to date, the solar reactors developed to facilitate the STWS reactions, and the effects of operating conditions—including the recent innovation of elevated oxidant pressure—on efficiency. To conclude the review, a perspective on the future optimization of STWS is provided.This article is categorized under:
Sustainable Energy > Solar Energy
Emerging Technologies > Hydrogen and Fuel Cells
Emerging Technologies > New Fuels