bluuebunny/crossref_metadata_2025 huggingface dataset:
Antimicrobial susceptibility and serovars of Salmonella from chickens and humans in Ibadan, Nigeria
Authors: Fashae Kayode , Ogunsola Folasade , Aarestrup Frank M , Hendriksen Rene S
Published: September 2010

Background: This study determines the prevalence and antibiotic resistance of Salmonella serovars from humans and chickens in Ibadan, Nigeria, in 2004-2007. Methodology: A total of 991 blood samples were collected from patients in 2004 to 2005 and 641 fecal samples were collected from poultry farms in 2007. All Salmonella isolates were serotyped and tested for antimicrobial susceptibility. Results: Thirty-nine (4%) Salmonella isolates were obtained from human blood and 70 (11%) from chicken fecal samples. The human isolates revealed nine different serovars; 82% were non-typhoidal Salmonella and 18% were (S. Typhi). The majority of serovars from humans were S. Enteritidis (33%), S. Dublin (18%), and S. Typhimurium (18%). Resistance to chloramphenicol, sulfamethoxazole, trimethoprim, and ampicillin ranged from 36% to 59% for the human isolates. Eight different serovars were obtained from chickens; S. Virchow (71%) predominated. A high frequency (87%) of reduced susceptibility to ciprofloxacin was observed among the chicken isolates. A high frequency of resistance to tetracycline (93%), nalidixic acid (81%), and sulfamethoxazole (87%) was observed. Rare serovars such as S. Apapa, S. Mouschaui, S. Jukestown, S. Oritamerin, and S. Onireke were isolated from both humans and chickens. Identical serovars were not found among human and chicken isolates. Conclusions: This study indicates that chickens are not a reservoir of Salmonella causing bacteraemia among humans in Ibadan, Nigeria. Studies locating the reservoirs responsible for invasive salmonellosis in humans are needed. Controls and targeted interventions against S. Virchow and the frequent occurrence of antimicrobial resistance in chickens should be initiated to prevent the spread of this serovar.
Fostering Cross-Cultural Understanding Through E-Learning: Russian-American Forum Case-Study.
Authors: Talalakina Ekaterina V.
Published: September 2010

Abstractâ?? The importance of cross-cultural understanding is accelerated nowadays by globalization and joint efforts of different countries in the face of global challenges. Countriesâ?? educational systems display attempts to incorporate cross-cultural studies in their curricula across all stages of formal learning. Many higher education institutions offer special courses aimed at promoting cross-cultural studies. One of the tools used to facilitate the process is e-learning. The present article examines the case study of an internet-based collaboration between two higher education institutions â?? State University Higher School of Economics in Russia and Champlain College in the USA â?? in fostering cross-cultural understanding.

The project is based on the study of individualistic and collectivistic values within the framework of two corresponding courses studied at both institutions. The topicality of the study is determined by the growing importance of the cooperation of two countries on the international affairs arena, on the one hand, and the fundamental differences of the countriesâ?? underlying value system, on the other. In particular, a post-soviet Russia is generally viewed as a developing democracy representing the collectivistic end of the value spectrum, whereas the USA is considered as an extreme case of individualistic value system.

The comparison and contrast of the two systems conducted simultaneously by the representatives of both cultures (students of the two universities) within a specifically built internet forum comprises the base of the project. The case study covers the projectâ??s objectives, its background, the rationale behind its content choice, the design of the e-learning tool, the profile of the participants of the project, its implementation stages and its outcome.

The major findings of the case study deal with the process of building cross-cultural awareness, reinforcing studentsâ?? analytical skills and providing them with a research incentive, fostering self-reflection, values projection from one culture onto the other, drawing the areas of their intersection, which, finally, result in cross-cultural understanding. The results of the study are assessed at quantative and qualitative levels.
Automated Assessment, Face to Face
Authors: Al-Sayyed Rizik M. H. , Hudaib Amjad , AL-Shboul Muhannad , Majdalawi Yousef , Bataineh Mohammed
Published: September 2010

This research paper evaluates the usability of automated exams and compares them with the paper-and-pencil traditional ones. It presents the results of a detailed study conducted at The University of Jordan (UoJ) that comprised students from 15 faculties. A set of 613 students were asked about their opinions concerning automated exams; and their opinions were deeply analyzed. The results indicate that most students reported that they are satisfied with using automated exams but they have suggestions to improve the automated exam deployment.
GE3D: A Virtual Campus for Technology-Enhanced Distance Learning
Authors: Grieu Jean , Lecroq Florence , Person Patrick , Galinho Thierry , Boukachour Hadhoum
Published: September 2010

A lot of learning systems platforms are used all over the world. But these conventional E-learning platforms aim at students who are used to work on their own. Our students are young (19 years old â?? 22 years old), and in their first year at the university. Following extensive interviews with our students, we have designed GE3D, an E-learning platform, according to their expectations and our criteria. In this paper, we describe the studentsâ?? demands, resulting from the interviews. Then, we describe our virtual campus. Even if our platform uses some elements coming from the 3D games world, it is always a pedagogical tool. Using this technology, we developed a 3D representation of the real world. GE3D is a multi-users tool, with a synchronous technology, an intuitive interface for end-users and an embedded Intelligent Tutoring System to support learners. We also describe the process of a lecture on the Programmable Logic Controllers (PLCâ??s) in this new universe.
Oracle against Israel’s social injustices: A rhetorical analysis of Amos 2:6−8
Authors: Mamahit Ferry Y. , Venter Pieter M.
Published: September 2010

This article applied rhetorical analysis to an analysis of Amos’ prophetic oracle against Israel’s social injustices in Amos 2:6–8. The prophet uses a major rhetorical genre, namely judicial rhetoric, and several smaller rhetorical devices including the oracle against the nations, geographical chiasmus, numerical formula (the N+1 formula), the sevenfold structure, rhetorical entrapment, repetition, the war oracle, parallel structure and chiasms. These devices are utilised by Amos to make a persuasive appeal to his audience to respond to divine indictment.
A combined observational and modeling approach to study modern dust transport from the Patagonia desert to East Antarctica
Authors: Gassó S. , Stein A. , Marino F. , Castellano E. , Udisti R. , Ceratto J.
Published: September 2010

Abstract. The understanding of present atmospheric transport processes from Southern Hemisphere (SH) landmasses to Antarctica can improve the interpretation of stratigraphic data in Antarctic ice cores. In addition, long range transport can deliver key nutrients normally not available to marine ecosystems in the Southern Ocean and may trigger or enhance primary productivity. However, there is a dearth of observational based studies of dust transport in the SH. This work aims to improve current understanding of dust transport in the SH by showing a characterization of two dust events originating in the Patagonia desert (south end of South America). The approach is based on a combined and complementary use of satellite retrievals (detectors MISR, MODIS, GLAS, POLDER, OMI), transport model simulation (HYSPLIT) and surface observations near the sources and aerosol measurements in Antarctica (Neumayer and Concordia sites). Satellite imagery and visibility observations confirm dust emission in a stretch of dry lakes along the coast of the Tierra del Fuego (TdF) island (~54° S) and from the shores of the Colihue Huapi lake in Central Patagonia (~46° S) in February 2005. Model simulations initialized by these observations reproduce the timing of an observed increase in dust concentration at the Concordia Station and some of the observed increases in atmospheric aerosol absorption (here used as a dust proxy) in the Neumayer station. The TdF sources were the largest contributors of dust at both sites. The transit times from TdF to the Neumayer and Concordia sites are 6–7 and 9–10 days respectively. Lidar observations and model outputs coincide in placing most of the dust cloud in the boundary layer and suggest significant deposition over the ocean immediately downwind. Boundary layer dust was detected as far as 1800 km from the source and ~800 km north of the South Georgia Island over the central sub-Antarctic Atlantic Ocean. Although the analysis suggests the presence of dust at ~1500 km SW of South Africa five days after, the limited capabilities of existing satellite platforms to differentiate between aerosol types do not permit a definitive conclusion. In addition, the model simulations show dust lifting to the free troposphere as it travels south but it could not be confirmed by the satellite observations due to cloudiness. This work demonstrates that complementary information from existing transport models, satellite and surface data can yield a consistent picture of the dust transport from the Patagonia desert to Antarctica. It also illustrates the limitation of using any of these approaches individually to characterize the transport of dust in a heavily cloudy area.
Joint spatial variability of aerosol, clouds and rainfall in the Himalayas from satellite data
Authors: Shrestha P. , Barros A. P.
Published: September 2010

Abstract. Satellite-based precipitation, Aerosol Optical Depth (AOD), Cloud Optical Depth (COD), and Aerosol Index (AI) data were used to characterize the linkages among landform and the intra-annual variability of aerosols, cloudiness and rainfall in the Himalayas using empirical orthogonal function (EOF) analysis. The first modes of AOD and AI show the presence of two branches of dust aerosol: over the Indus river basin and the Thar desert with a sharp west-east gradient parallel to the southern slopes of the Himalayas – the Southern Branch; and the second against the slopes of the Tian Shan and over the Takla Makan desert in the Tibetan Plateau-the Northern branch. The third EOF mode of AOD accounts for about 7% of overall variance of AOD. It is attached to the foothills of the Himalayas east of the Aravalli range peaking in April-May-June followed by a sharp decrease in July during the first active phase of the monsoon. The first and second EOF modes of COD and precipitation show consistent patterns against the central and eastern Himalayas and along the ocean-land boundaries in western India and the Bay of Bengal. The break in cloudiness and rainfall between the winter and the monsoon seasons is captured well by the second EOF mode of COD and rainfall concurrent with the aerosol build up mode (April–May) over the region depicted by the third mode of AOD. The results show that the Aravalli range separates the two different modes of aerosol variability over northern India with dust aerosols to the west and polluted mixed aerosols to the east consistent with its role in regional circulation and precipitations patterns as per Barros et al. (2004) and Chiao and Barros (2007). SVD analysis between rainfall, COD and AOD showed a pattern of aerosol loading (resembling EOF3 of MODIS AOD) extending from 80° E~90° E that peaks during the winter and pre-monsoon seasons and decays abruptly during the monsoon: the regions of aerosol buildup during the pre-monsoon season and the areas of high rainfall/cloudiness during the monsoon are collocated and have opposite signs suggesting aerosol-cloud-rainfall interaction. It is proposed that the third EOF of AOD maps the area where aerosol-cloud-rainfall interactions play an important role in the regional hydro-climatology.
Numerically exact computation of the optical properties of light absorbing carbon aggregates for wavelength of 200 nm–12.2 μm
Authors: Kahnert M.
Published: September 2010

Abstract. The optical properties of externally mixed light absorbing carbon (LAC) aggregates are computed over the spectral range from 200 nm–12.2 μm by use of the numerically exact superposition T-matrix method. The spectral computations are tailored to the 14-band radiation model employed in the Integrated Forecasting System operated at the European Centre for Medium Range Weather Forecast. The size- and wavelength dependence of the optical properties obtained with the fractal aggregate model differs significantly from corresponding results based on the homogeneous sphere approximation, which is still commonly employed in climate models. The computational results are integrated into the chemical transport model MATCH (Multiple-scale Atmospheric Transport and CHemistry modelling system) to compute 3-D fields of size-averaged aerosol optical properties. Computational results obtained with MATCH are coupled to a radiative transfer model to compute the shortwave radiative impact of LAC. It is found that the fractal aggregate model gives a shortwave forcing estimate that is twice as high as that obtained with the homogeneous sphere approximation. Thus previous estimates based on the homogeneous sphere model may have substantially underestimated the shortwave radiative impact of freshly emitted LAC.
Technical Note: Formal blind intercomparison of HO2 measurements in the atmosphere simulation chamber SAPHIR during the HOxComp campaign
Authors: Fuchs H. , Brauers T. , Dorn H.-P. , Harder H. , Häseler R. , Hofzumahaus A. , Holland F. , Kanaya Y. , Kajii Y. , Kubistin D. , Lou S. , Martinez M. , Miyamoto K. , Nishida S. , Rudolf M. , Schlosser E. , Wahner A. , Yoshino A. , Schurath U.
Published: September 2010

Abstract. Hydroperoxy radical (HO2) concentrations were measured during the formal blind intercomparison campaign HOxComp carried out in Jülich, Germany. Three instruments detected HO2 via chemical conversion to hydroxyl radicals (OH) and subsequent detection of the sum of OH and HO2 by laser induced fluorescence (LIF). Instruments sampled ambient air for three days and were attached to the atmosphere simulation chamber SAPHIR during the second part of the campaign. Six experiments of one day each were conducted in SAPHIR, where air masses were homogeneously mixed, in order to investigate the performance of instruments and to determine potential interferences of measurements under well-controlled conditions. Linear correlation coefficients between measurements of the LIF instruments are generally high and range from 0.82 to 0.98. However, the agreement between measurements is variable. The regression analysis of the entire data set of measurements in SAPHIR yields slopes between 0.69 to 1.26 and intercepts are smaller than typical atmospheric daytime concentrations (less than 1 pptv). The quality of fit parameters improves significantly, when data are grouped into data subsets of similar water vapor concentrations. Because measurements of LIF instruments were corrected for a well-characterized water dependence of their sensitivities, this indicates that an unknown factor related to water vapor affected measurements in SAPHIR. Measurements in ambient air are also well correlated, but regression parameters differ from results obtained from SAPHIR experiments. This is most likely caused by sampling different air masses at the slightly distant locations of instruments.
Comparing plasma bubble occurrence rates at CHAMP and GRACE altitudes during high and low solar activity
Authors: Xiong C. , Park J. , Lühr H. , Stolle C. , Ma S. Y.
Published: September 2010

Abstract. Based on the multi-year data base (2001–2009) of CHAMP Planar Langmuir Probe (PLP) data and GRACE K-Band Ranging (KBR1B) data, typical features of ionospheric plasma irregularities are studied at the altitudes of CHAMP (300–400 km) and GRACE (~500 km). The phenomena we are focusing on are the equatorial plasma bubbles (EPBs). Similar seasonal/longitudinal (S/L) distributions of EPB have been found at both CHAMP and GRACE altitudes during solar active and quiet years. Peak EPB occurrence rates, defined as number of events within an S/L bin divided by the number of passes over that bin, decrease from the high and moderate solar flux period (2001–2005) to the low solar flux period (2005–2009) from 80% to 60% and 60% to 40% at CHAMP and GRACE altitudes, respectively. On average the occurrence rate increases linearly with solar flux at about the same rate at CHAMP and GRACE. For high flux levels (P10.7>200) non-linear increases are observed at GRACE. The occurrence rate increases rapidly after 19:00 local time (LT) during high solar flux periods. Around solar minimum rates increase more gently and peak around 22:00 LT. The highest occurrence rates are encountered at latitudes around 10° north and south of the dip equator. Results from the two altitudes support the notion that EPBs form regions of depleted plasma along geomagnetic fluxtubes. It is shown for the first time that in regions of high occurrence rates EPBs are associated with fluxtubes reaching greater apex heights than those in regions of low rates.
Late Holocene climate variability in the southwestern Mediterranean region: an integrated marine and terrestrial geochemical approach
Authors: Martín-Puertas C. , Jiménez-Espejo F. , Martínez-Ruiz F. , Nieto-Moreno V. , Rodrigo M. , Mata M. P. , Valero-Garcés B. L.
Published: September 2010

Abstract. A combination of marine (Alboran Sea cores, ODP 976 and TTR 300 G) and terrestrial (Zoñar Lake, Andalucia, Spain) paleoclimate information using geochemical proxies provides a high resolution reconstruction of climate variability and human influence in southwestern Mediterranean region for the last 4000 years at inter-centennial resolution. Proxies respond to changes in precipitation rather than temperature alone. Our archive documents a succession of dry and wet periods coherent with the North Atlantic climate signal. Drier stages occurred prior to 2.7 cal ka BP, well-correlated with the global aridity crisis of the third-millennium BC, and during the Medieval Warm Period (1.4–0.7 cal ka BP). Wetter conditions prevailed from 2.7 to 1.4 cal ka BP and after the Medieval Warm Period and the onset of the Little Ice Age. Hydrological signatures during the Little Ice Age are highly variable but consistent with more humidity that the period before. Additionally, Pb anomalies in sediments at the end of Bronze Age suggest anthropogenic pollution earlier than the Roman Empire development in the Iberian Peninsula. The evolution of the climate in the study area during the Late Holocene confirms the see-saw pattern previously shown between eastern and western Mediterranean regions and suggests a higher influence of the North Atlantic dynamics in the western Mediterranean.
Development cycle 2 of the Modular Earth Submodel System (MESSy2)
Authors: Jöckel P. , Kerkweg A. , Pozzer A. , Sander R. , Tost H. , Riede H. , Baumgaertner A. , Gromov S. , Kern B.
Published: September 2010

Abstract. The Modular Earth Submodel System (MESSy) is an open, multi-institutional project providing a strategy for developing comprehensive Earth System Models (ESMs) with highly flexible complexity. The first version of the MESSy infrastructure and process submodels, mainly focusing on atmospheric chemistry, has been successfully coupled to an atmospheric General Circulation Model (GCM) expanding it into an Atmospheric Chemistry GCM (AC-GCM) for nudged simulations and into a Chemistry Climate Model (CCM) for climate simulations. Here, we present the second development cycle of MESSy, which comprises (1) an improved and extended infrastructure for the basemodel independent coupling of process-submodels, (2) new, highly valuable diagnostic capabilities for the evaluation with observational data and (3) an improved atmospheric chemistry setup. With the infrastructural changes, we place the headstone for further model extensions from a CCM towards a comprehensive ESM. The new diagnostic submodels will be used for regular re-evaluations of the continuously further developing model system. The updates of the chemistry setup are briefly evaluated.
Tsunami early warning and decision support
Authors: Steinmetz T. , Raape U. , Teßmann S. , Strobl C. , Friedemann M. , Kukofka T. , Riedlinger T. , Mikusch E. , Dech S.
Published: September 2010

Abstract. An innovative newly developed modular and standards based Decision Support System (DSS) is presented which forms part of the German Indonesian Tsunami Early Warning System (GITEWS). The GITEWS project stems from the effort to implement an effective and efficient Tsunami Early Warning and Mitigation System for the coast of Indonesia facing the Sunda Arc along the islands of Sumatra, Java and Bali. The geological setting along an active continental margin which is very close to densely populated areas is a particularly difficult one to cope with, because potential tsunamis' travel times are thus inherently short. National policies require an initial warning to be issued within the first five minutes after an earthquake has occurred. There is an urgent requirement for an end-to-end solution where the decision support takes the entire warning chain into account. The system of choice is based on pre-computed scenario simulations and rule-based decision support which is delivered to the decision maker through a sophisticated graphical user interface (GUI) using information fusion and fast information aggregation to create situational awareness in the shortest time possible. The system also contains risk and vulnerability information which was designed with the far end of the warning chain in mind – it enables the decision maker to base his acceptance (or refusal) of the supported decision also on regionally differentiated risk and vulnerability information (see Strunz et al., 2010). While the system strives to provide a warning as quickly as possible, it is not in its proper responsibility to send and disseminate the warning to the recipients. The DSS only broadcasts its messages to a dissemination system (and possibly any other dissemination system) which is operated under the responsibility of BMKG – the meteorological, climatological and geophysical service of Indonesia – which also hosts the tsunami early warning center. The system is to be seen as one step towards the development of a "system of systems" enabling all countries around the Indian Ocean to have such early warning systems in place. It is within the responsibility of the UNESCO Intergovernmental Oceonographic Commission (IOC) and in particular its Intergovernmental Coordinating Group (ICG) to coordinate and give recommendations for such a development. Therefore the Decision Support System presented here is designed to be modular, extensible and interoperable (Raape et al., 2010).
“Inoculation” to Resist Misinformation
Authors: van der Linden Sander , Roozenbeek Jon
Published: May 2024

This JAMA Insights in the Communicating Medicine series explores the concept of “prebunking,” a psychological inoculation technique that could help prevent the spread of misinformation.
On‐Demand Activatable and Integrated Bioorthogonal Nanocatalyst against Biofilm‐Associated Infections
Authors: Sun Yue , Zhao Huisi , Pu Fang , Liu Hao , Chen Li , Ren Jinsong , Qu Xiaogang
Published: May 2024

Bioorthogonal chemistry has emerged as a powerful tool for manipulating biological processes. However, difficulties in controlling the exact location and on‐demand catalytic synthesis limit its application in biological systems. Herein, this work constructs an activatable bioorthogonal system integrating a shielded catalyst and prodrug molecules to combat biofilm‐associated infections. The catalytic species is activated in response to the hyaluronidase (HAase) secreted by the bacteria and the acidic pH of the biofilm, which is accompanied by the release of prodrugs, to achieve the bioorthogonal catalytic synthesis of antibacterial molecules in situ. Moreover, the system can produce reactive oxygen species (ROS) to disperse bacterial biofilms, enabling the antibacterial molecules to penetrate the biofilm and eliminate the bacteria within it. This study promotes the design of efficient and safe bioorthogonal catalysts and the development of bioorthogonal chemistry‐mediated antibacterial strategies.
Deep Learning‐Assisted Design of Bilayer Nanowire Gratings for High‐Performance MWIR Polarizers
Authors: Lee Junghyun , Oh Junhyuk , Chi Hyung‐gun , Lee Minseok , Hwang Jehwan , Jeong Seungjin , Kang Sang‐Woo , Jee Haeseong , Bae Hagyoul , Hyun Jae‐Sang , Kim Jun Oh , Kim Bongjoong
Published: May 2024

Optical metamaterials have revolutionized imaging capabilities by manipulating light‐matter interactions at the nanoscale beyond the diffraction limit. Bilayer nanowire grating configurations exhibit significant potential as exceptional elements for high‐performance polarimetric imaging systems. However, conventional computational approaches for predicting electromagnetic responses are time‐consuming and labor‐intensive, and thereby, the practical implementation remains challenging through an iterative design, analysis, and fabrication process. Here, a deep learning‐based design process is presented utilizing an artificial neural network (ANN) trained on finite element method (FEM) simulations that enables the prediction of bilayer nanowire gratings‐based electromagnetic responses. The study validates predictions through nanoimprinted bilayer nanowire gratings, demonstrating the reliability of the ANN's predictions. Furthermore, the research identifies critical geometric parameters significantly influencing transverse magnetic (TM) and transverse electric (TE) transmission. The ANN model effectively tailors design for specific mid‐wavelength infrared (MWIR) wavelengths, which may provide a practical tool for rapidly designing and optimizing metamaterial for high‐performance polarizers.
High‐Efficiency Fiber‐Chip Edge Coupler for Near‐Ultraviolet Integrated Photonics
Authors: Du Yuhan , Ji Xingchen , Xie Weiqiang , He Yu , Zhang Yong , Tian Meng , Su Yikai
Published: May 2024

Integrated photonics is demanded in applications operating at ultraviolet to visible wavelengths, such as atomic/quantum systems, on‐chip broadband receivers, and far‐field structured illumination autofluorescence microscopy. A fundamental challenge in these applications is efficient edge coupling from a single‐mode fiber (SMF) to on‐chip photonic components, which is critical for on‐chip integration. In this paper, a high‐efficiency edge coupler based on an alumina‐on‐insulator platform is introduced and experimentally validated. The coupler employs a symmetric double‐tip taper and a multimode interference (MMI)‐based optical combiner. The double‐tip taper effectively expands the mode field diameter at the chip facet to match that of the SMF at the initial stage. Then the MMI‐based combiner efficiently combines the two channels in the taper into a highly confined strip waveguide. A coupling loss of 2.85 dB/facet has been achieved for the transverse magnetic mode at the wavelength of 407 nm, which is the lowest insertion loss for fiber‐chip coupling on this platform to the best of the knowledge. The design can significantly reduce the insertion loss associated with fiber‐chip coupling, offering a key component for diverse areas ranging from atomic/quantum photonic integrated circuits and ultra‐high capacity communications to optical microscopes.
Advanced Biomimetic and Biohybrid Magnetic Micro/Nano‐Machines
Authors: Murali Nandan , Das Shashank Bhushan , Yadav Satyam , Rainu Simran Kaur , Singh Neetu , Betal Soutik
Published: May 2024

Biomimetic and biohybrid micro/nano‐structures involve the replication and creation of technologies, structures, and materials based on biological systems at the micrometer and nanometer scale. These strategies harness the natural biological principles to develop innovative treatment methods and advanced microstructure devices for noninvasive therapies. In this study, a detailed overview of fabrication processes, magnetically assisted locomotive techniques, and potential applications of biomimetic and biohybrid micro/nano‐machines are presented. The latest advancements in magnetically actuated biomimetic structures, such as annelid‐worm‐like microswimmers, jellyfish‐shaped microparticles, fish‐shaped microswimmers, and walnut‐shaped micromotors are explored. Additionally, the magnetic biohybrid systems, including sunflower seed‐based micro‐perforators, nanomotors extracted from the bamboo stem, sperm cell‐based micromotors, bacteria‐based robots, scaffold‐based microrobots, DNA‐based micromotors, microalgae‐based microswimmers, and red blood cell‐based microswimmers are also examined. A thorough investigation of the magnetically assisted locomotive behavior of these microstructure devices in biological Newtonian fluids, featuring cork‐screw motion, undulatory motion, surface wrinkling motion, traveling wave‐like motion, and ciliary stroke motion is discussed. Furthermore, unprecedented and innovative treatment methods developed using these minuscule devices such as cervical cancer treatment using tetrapod hybrid sperm micromotors, tissue regeneration using silk fibroin protein‐based magnetic microscale scaffolds, and doxorubicin drug delivery using mushroom‐based microrobots is extensively presented.
Fluid‐Driven Director‐Field Design Enables Versatile Deployment of Multistable Structures
Authors: Veksler Yaron , Ben‐Abu Ezra , Gat Amir D.
Published: May 2024

Shape‐morphing structures capable of significantly altering shape and volume play a crucial role in diverse applications, ranging from soft robotics to minimally invasive surgery, deployable structures, and space exploration. This article presents an approach to achieve simple and controllable morphing onto multiple stable complex 3D surfaces—a long sought after goal in the field. The method is based on interconnected multistable straw‐like deformable tubes, constrained by rigid links that can be assembled and connected in many different ways. By leveraging the director‐field theory, the links and their assembly process are modeled and designed to reach a variety of desired final operational shapes from a single base‐structure. The use of viscous‐fluid actuation enables precise control and predictable shape‐morphing while facilitating a wide range of configurations through inflation and deflation sequences, all with a single input.
On the History of the Lennard‐Jones Potential
Authors: Lenhard Johannes , Stephan Simon , Hasse Hans
Published: May 2024

This contribution describes two episodes from the history of the Lennard‐Jones (LJ) potential. The first, located in the 1920s and 1930s, is about a computational approach that aimed at pragmatics rather than truth and that remained remarkably robust when quantum theory arrived. The second episode covers the birth of the LJ substance in 1964. Due to increasing interest in computer methods, simulated model substances became objects on their own, the prime targets of investigation. The history of the LJ potential and substance exemplifies the dynamic relationship between prediction, theory, mathematization, and computer instrumentation.
Structural Improvement and Numerical Simulation of a Perforated Distributor in an Adsorption Tower
Authors: Hao Zhao , Zhang Tao , Lv Li , Tang Wenxiang , Tang Shengwei
Published: May 2024

A “closed” perforated plate distributor was proposed to improve the gas distribution in an industrial adsorption tower. Compared with the industrial perforated plate distributor, the designed distributor restricts the space for the disordered movement of gas under the perforated plate. The new distributor effectively converts the gas from the initial axial flow on the inlet section to the axial flow on the tower section to improve the gas uniformity. In addition, the gas velocity at the edge of the inlet cross section of the adsorbent bed is increased by opening holes on the bottom plate. The uniformity of gas distribution is further improved. The simulation method in this study and the distribution performance of the “closed” perforated plate distributor have been verified by experiments.
How Metal/Insulator Interfaces Enable an Enhancement of the Hydrogen Evolution Reaction Kinetics
Authors: Maier Thomas L. , T. de Kam Lucas B. , Golibrzuch Matthias , Angerer Tina , Becherer Markus , Krischer Katharina
Published: May 2024

The nanostructuring of electrodes is a common way of increasing electrocatalytic activity. Yet, the fact that the presence of insulating material in nanostructured composites can have a positive effect on efficiency was an unexpected recent finding. The rate enhancement has been linked to different electric fields at the insulator and metal interfaces, facilitating enhanced transport of reaction products into the bulk electrolyte. In this article, we further uncover the origin of the rate enhancement with parameter studies and simulations. We experimentally investigate various parameter dependencies of the alkaline Hydrogen Evolution Reaction (HER) on well‐defined nanometer‐sized Au arrays embedded in a silicon nitride insulating layer. We find a significant enhancement of the HER for all experimental conditions and opposite activity trends with pH, electrolyte concentration and the cationic species compared to a continuous Au electrode. Using a mean field model, we quantify the electrostatic interfacial pressure above the Au and the insulator patches. Combining the double layer simulations with rate equations, we demonstrate that all parameter variations can be consistently explained by the fact that the double layer structure above the insulator patches is much less rigid than above the metal islands and is independent of the applied potential.
Materials for 3D Printed Metal and Metal‐Ion Batteries
Authors: García Rodríguez Tomás , Medina Santos Jesus I. , Coelho João , Pinilla Sergio
Published: May 2024

The review provides an overview of the latest innovations, trends, and challenges in the field of 3D‐printed metal and metal‐ion batteries. It focuses on the materials used in the printing of batteries, including electrodes, electrolytes, and other electroactive components. Compared to other high‐quality reviews on the topic, this review provides a broader selection of materials that are expected to gain attention in the next few years, such as redox‐active polymers and metal‐organic frameworks. This work gives an overview and insight into the latest trends in printing techniques as well as a statistical review of their uses and strengths. We have also gathered the latest works done for each of the material types, and we have taken the opportunity to put them in context and use them to exemplify in which direction is the field going. The review concludes with a critical view of the challenges ahead and a discussion of the direction that the field is taking as well as the external factors that might help to define its future.
Revealing the origin of single‐atom W activity in H2O2 electrocatalytic production: Charge symmetry‐breaking
Authors: Jing Changfei , Ding Junyang , Jia Peipei , Jin Mengmeng , Zhou Lihui , Liu Xijun , Luo Jun , Dai Sheng
Published: May 2024

The low‐energy electrochemical production of hydrogen peroxide (H2O2) has garnered significant attention as a viable alternative to traditional industrial routes, with the goal of achieving carbon neutrality. For their H2O2 selectivity in the two‐electron oxygen reduction reaction (ORR), the coordination environment of tungsten (W)‐based materials is critical. In this study, atomically dispersed W single atoms were immobilized on N‐doped carbon substrates by a facile pyrolysis method to obtain a W single‐atom catalyst (W‐SAC). The coordination environment of an isolated W single atom with a tetra‐coordinated porphyrin‐like structure in W‐SAC was determined by X‐ray photoelectron spectroscopy and X‐ray absorption spectroscopy analysis. Notably, the as‐prepared W‐SAC showed superior two‐electron ORR activity in 0.1 M KOH solution, including high onset potential (0.89 V), high H2O2 selectivity (82.5%), and excellent stability. By using differential phase contrast‐scanning transmission electron microscopy and density functional theory calculations, it is revealed that the charge symmetry‐breaking of W atoms changes the adsorption behavior of the intermediates, leading to enhanced reactivity and selectivity for two‐electron ORR. This work broadens the avenue for understanding the charge transfer of W‐based electrocatalytic materials and the in‐depth reaction mechanism of SACs in two‐electron ORR.
Low‐lying LUMO Boosts Conductance in Antiaromatic Dibenzopentalene Versus Aromatic Analogues
Authors: Schmidt Maximilian , Abellán Vicente Lydia , González M. Teresa , Zotti Linda A. , Esser Birgit , Leary Edmund
Published: May 2024

Antiaromaticity is a fundamental concept in chemistry, but the study of molecular wires incorporating antiaromatic units is limited. Despite initial predictions, very few studies show that antiaromaticity has a beneficial effect on electron transport. Dibenzo[a,e]pentalene (DBP) is a stable structure that displays appreciable antiaromaticity within the five‐membered rings of the pentalene core. We have investigated derivatives of DBP furnished with pyridyl (Py) and F4‐pyridyl (PyF4) anchor groups, and compared the conductance with purely aromatic phenyl and anthracene analogues. We find that the low‐bias conductance of DBP‐Py is approximately 60 % larger than that of the anthracene analogue Anth‐Py and 250 % larger compared to the phenyl derivative Ph‐Py. This is due to a better alignment of the LUMO with the gold Fermi level, which we confirm by conductance‐voltage spectroscopy where the conductance of DBP‐Py shows the greatest voltage‐dependence. The F4‐pyridyl compounds, which have lower LUMO energies compared to the pyridyl analogues, did not, however, form detectable molecular junctions. The strongly electron‐withdrawing fluorine atoms reduce the donor capability of the nitrogen lone‐pair to the point where stable N−Au bonds no longer form.
Exploring a Lux® i‐Amylose‐3 column in normal phase and polar‐organic mode for chiral separation of cathinone derivatives and pyrovalerones using high‐performance liquid chromatography
Authors: Seibert Elisabeth , Götz Katharina , Schmid Martin G.
Published: May 2024

Each year, new psychoactive substances appear on the global drug market leading to constant changes. Most of these compounds with stimulating effect possess a chiral center, thus leading to two enantiomers with presumably different pharmacological properties. Among them, synthetic cathinones, often misleadingly traded as “bath salts,” play an important role. There is little knowledge about the distinct effect of the enantiomers. The aim of this study was to test a commercially available Lux® i‐Amylose‐3 column by HPLC‐UV for enantiorecognition of cathinone derivatives. Overall, 80 compounds were tested in normal phase mode, where 75 substances were separated under initial conditions. After method optimization, at least partial separation was achieved for the remaining compounds. The same set of substances was measured in polar‐organic mode, where 63 analytes were resolved into their enantiomers under initial conditions with very short retention times. Both modes showed complementary results for the individual compounds. Furthermore, the tested methods proved to be suitable for differentiation of positional isomers, which can be useful for drug checking programs. All measurements were carried out under isocratic conditions, and intraday and interday repeatability tests were performed.
Evaluation of the effect of different core substrates on the accuracy of intraoral scanners
Authors: Khoshkhahesh Maryam , Enteghad Shabnam , Aghasadeghi Kiana , Farzin Mitra , Taghva Masumeh , Mosadad Seyed Ali
Published: May 2024

Background

The aim of this study was to determine if different types of core substrates have any effect on the trueness and precision of digital intraoral impressions.

Material and Methods

A customized typodont with four similar cores of natural dentine, composite, metal (Ni‐Cr), and zirconia in the position of premolars was fabricated. The study model was scanned five times with two types of intraoral scanners (Carestream 3600 and 3Shape Trios 3), and a reference standard scan was obtained using a laboratory scanner (3shape D1000). A metrology software (Geomagic X) was used to align the data of experimental scans and the reference scan to determine deviation values (trueness). Precision values were calculated with random superimposition in each intraoral scanner group. The Kruskal–Wallis test was used to compare differences between different substrates, and the Mann–Whitney test was used to compare the average values between the two scanners.

Results

Trios 3 was found to be significantly truer and more precise than Carestream 3600 (p value = .005, <0.001). There were no significant differences in the trueness of different substrates when they were scanned by Trios 3, while different materials showed significantly different trueness values in the Carestream 3600 group (p value = .003). Dentin showed the best trueness, and zirconia performed worse than other substrates. Regarding the precision of the scanners, neither of the scanners was affected by the type of scanning substrate.

Conclusion

For Carestream 3600, substrate type did impact the trueness of intraoral scans, with dentin and zirconia showing the highest and lowest accuracy, respectively, while Trios 3 was similarly accurate across all substrates. Trios 3 had both higher trueness and precision than Carestream 3600.
T‐cell immunity against Severe Acute Respiratory Syndrome Coronavirus 2 proteins in patients with type 1 diabetes
Authors: Palmieri Camillo , Santamaria Gianluca , Cristiani Costanza Maria , Garofalo Cinzia , Tham Christine Y. L. , Abatino Antonio , Cutruzzolà Antonio , Parise Martina , Aversa Ilenia , Malanga Donatella , Gallo Raffaella , Cuda Giovanni , Viglietto Giuseppe , Costanzo Francesco , Bertoletti Antonio , Gnasso Agostino , Irace Concetta
Published: May 2024

Aims

Individuals with type 1 diabetes (T1D) do not appear to have an elevated risk of severe Coronavirus Disease 19 (COVID‐19). Pre‐existing immune reactivity to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS‐CoV‐2) in unexposed individuals may serve as a protective factor. Hence, our study was designed to evaluate the existence of T cells with reactivity against SARS‐CoV‐2 antigens in unexposed patients with T1D.

Materials and methods

Peripheral blood mononuclear cells (PBMCs) were collected from SARS‐CoV‐2 unexposed patients with T1D and healthy control subjects. SARS‐CoV‐2 specific T cells were identified in PBMCs by ex‐vivo interferon (IFN)γ‐ELISpot and flow cytometric assays. The epitope specificity of T cells in T1D was inferred through T Cell Receptor sequencing and GLIPH2 clustering analysis.

Results

T1D patients unexposed to SARS‐CoV‐2 exhibited higher rates of virus‐specific T cells than controls. The T cells primarily responded to peptides from the ORF7/8, ORF3a, and nucleocapsid proteins. Nucleocapsid peptides predominantly indicated a CD4+ response, whereas ORF3a and ORF7/8 peptides elicited both CD4+ and CD8+ responses. The GLIPH2 clustering analysis of TCRβ sequences suggested that TCRβ clusters, associated with the autoantigens proinsulin and Zinc transporter 8 (ZnT‐8), might share specificity towards ORF7b and ORF3a viral epitopes. Notably, PBMCs from three T1D patients exhibited T cell reactivity against both ORF7b/ORF3a viral epitopes and proinsulin/ZnT‐8 autoantigens.

Conclusions

The increased frequency of SAR‐CoV‐2‐ reactive T cells in T1D patients might protect against severe COVID‐19 and overt infections. These results emphasise the long‐standing association between viral infections and T1D.
Growth of brown trout in the wild predicted by embryo stress reaction in the laboratory
Authors: Bylemans Jonas , Marques da Cunha Lucas , Wilkins Laetitia G. E. , Nusbaumer David , Uppal Anshu , Wedekind Claus
Published: May 2024

Laboratory studies on embryos of salmonids, such as the brown trout (Salmo trutta), have been extensively used to study environmental stress and how responses vary within and between natural populations. These studies are based on the implicit assumption that early life‐history traits are relevant for stress tolerance in the wild. Here we test this assumption by combining two data sets from studies on the same 60 families. These families had been experimentally produced from wild breeders to determine, in separate samples, (1) stress tolerances of singly kept embryos in the laboratory and (2) growth of juveniles during 6 months in the wild. We found that growth in the wild was well predicted by the larval size of their full sibs in the laboratory, especially if these siblings had been experimentally exposed to a pathogen. Exposure to the pathogen had not caused elevated mortality among the embryos but induced early hatching. The strength of this stress‐induced change of life history was a significant predictor of juvenile growth in the wild: the stronger the response in the laboratory, the slower the growth in the wild. We conclude that embryo performance in controlled environments can be a useful predictor of juvenile performance in the wild.
High‐Safety Anode Materials for Advanced Lithium‐Ion Batteries
Authors: Yuan Kai , Lin Yu , Li Xiang , Ding Yufeng , Yu Peng , Peng Jian , Wang Jiazhao , Liu HuaKun , Dou Shixue
Published: May 2024

Lithium‐ion batteries (LIBs) play a pivotal role in today's society, with widespread applications in portable electronics, electric vehicles, and smart grids. Commercial LIBs predominantly utilize graphite anodes due to their high energy density and cost‐effectiveness. Graphite anodes face challenges, however, in extreme safety‐demanding situations, such as airplanes and passenger ships. The lithiation of graphite can potentially form lithium dendrites at low temperatures, causing short circuits. Additionally, the dissolution of the solid‐electrolyte‐interphase on graphite surfaces at high temperatures can lead to intense reactions with the electrolyte, initiating thermal runaway. This review introduces two promising high‐safety anode materials, Li4Ti5O12 and TiNb2O7. Both materials exhibit low tendencies towards lithium dendrite formation and have high onset temperatures for reactions with the electrolyte, resulting in reduced heat generation and significantly lower probabilities of thermal runaway. Li4Ti5O12 and TiNb2O7 offer enhanced safety characteristics compared to graphite, making them suitable for applications with stringent safety requirements. This review provides a comprehensive overview of Li4Ti5O12 and TiNb2O7, focusing on their material properties and practical applicability. It aims to contribute to the understanding and development of high‐safety anode materials for advanced LIBs, addressing the challenges and opportunities associated with their implementation in real‐world applications.