bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploring and machine learning structural instabilities in 2D materials
Authors: Manti Simone , Svendsen Mark Kamper , Knøsgaard Nikolaj R. , Lyngby Peder M. , Thygesen Kristian S.
Published: March 2023

We address the problem of predicting the zero-temperature dynamical stability (DS) of a periodic crystal without computing its full phonon band structure. Here we report the evidence that DS can be inferred with good reliability from the phonon frequencies at the center and boundary of the Brillouin zone (BZ). This analysis represents a validation of the DS test employed by the Computational 2D Materials Database (C2DB). For 137 dynamically unstable 2D crystals, we displace the atoms along an unstable mode and relax the structure. This procedure yields a dynamically stable crystal in 49 cases. The elementary properties of these new structures are characterized using the C2DB workflow, and it is found that their properties can differ significantly from those of the original unstable crystals, e.g., band gaps are opened by 0.3 eV on average. All the crystal structures and properties are available in the C2DB. Finally, we train a classification model on the DS data for 3295 2D materials in the C2DB using a representation encoding the electronic structure of the crystal. We obtain an excellent receiver operating characteristic (ROC) curve with an area under the curve (AUC) of 0.90, showing that the classification model can drastically reduce computational efforts in high-throughput studies.
Learning the right channel in multimodal imaging: automated experiment in piezoresponse force microscopy
Authors: Liu Yongtao , Vasudevan Rama K. , Kelley Kyle P. , Funakubo Hiroshi , Ziatdinov Maxim , Kalinin Sergei V.
Published: March 2023

We report the development and experimental implementation of the automated experiment workflows for the identification of the best predictive channel for a phenomenon of interest in spectroscopic measurements. The approach is based on the combination of ensembled deep kernel learning for probabilistic predictions and a basic reinforcement learning policy for channel selection. It allows the identification of which of the available observational channels, sampled sequentially, are most predictive of selected behaviors, and hence have the strongest correlations. We implement this approach for multimodal imaging in piezoresponse force microscopy (PFM), with the behaviors of interest manifesting in piezoresponse spectroscopy. We illustrate the best predictive channel for polarization-voltage hysteresis loop and frequency-voltage hysteresis loop areas is amplitude in the model samples. The same workflow and code are applicable for any multimodal imaging and local characterization methods.
A comparative blind study between skin biopsy and seed amplification assay to disclose pathological α-synuclein in RBD
Authors: Liguori R. , Donadio V. , Wang Z. , Incensi A. , Rizzo G. , Antelmi E. , Biscarini F. , Pizza F. , Zou Wq , Plazzi G.
Published: March 2023

To compare the diagnostic accuracy of the immunofluorescence (IF) technique and aSyn-seed amplification assay (aSyn-SAA) of skin and cerebrospinal fluid (CSF) in disclosing pathological α-syn in idiopathic idiopathic REM sleep behavior disorder (iRBD) as early phase of a synucleinopathy. We prospectively recruited 41 patients with iRBD and 40 matched clinical controls including RBD associated with type 1 Narcolepsy (RBD-NT1, 21 patients), iatrogenic causes (2 pt) or OSAS (6 pt) and 11 patients with peripheral neuropathies. IF from samples taken by skin biopsy and aSyn-SAA from skin and CSF samples were analysed blinded to the clinical diagnosis. IF showed a good diagnostic accuracy (89%) that was lower in the case of skin and CSF-based aSyn-SAA (70% and 69%, respectively) because of a lower sensitivity and specificity. However, IF showed a significant agreement with CSF aSyn-SAA. In conclusion, our data may favor the use of skin biopsy and aSyn-SAA as diagnostic tools for a synucleinopathy in iRBD.
Application of an algorithm to analyze patterns of intermittent oral corticosteroid use in asthma
Authors: Haughney John , Tran Trung N. , Heatley Heath , Bourdin Arnaud , Menzies-Gow Andrew , Jackson David J. , Maslova Ekaterina , Chapaneri Jatin , Skinner Derek , Carter Victoria , Chan Jeffrey Shi Kai , Price David
Published: March 2023

An algorithm to describe patterns of intermittent oral corticosteroid use in the UK (n = 476,167) found that one-third of patients receiving intermittent oral corticosteroids for asthma only had short gaps (<90 days) between oral corticosteroid prescriptions sometime during follow-up. The increasing frequency pattern was more likely in patients with greater asthma severity and with more short-acting β2-agonist use at baseline. Our approach may provide a clinically relevant representation of intermittent oral corticosteroid use in asthma.
Parallel tomography of quantum non-demolition measurements in multi-qubit devices
Authors: Pereira L. , García-Ripoll J. J. , Ramos T.
Published: March 2023

An efficient characterization of QND measurements is an important ingredient toward certifying and improving the performance and scalability of quantum processors. In this work, we introduce a parallel tomography of QND measurements that addresses single- and two-qubit readout on a multi-qubit quantum processor. We provide an experimental demonstration of the tomographic protocol on a 7-qubit IBM-Q device, characterizing the quality of conventional qubit readout as well as generalized measurements such as parity or measurement-and-reset schemes. Our protocol reconstructs the Choi matrices of the measurement processes, extracts relevant quantifiers—fidelity, QNDness, destructiveness—and identifies sources of errors that limit the performance of the device for repeated QND measurements. We also show how to quantify measurement crosstalk and use it to certify the quality of simultaneous readout on multiple qubits.
Evaluation of two terpene-derived polymers as consolidants for archaeological wood
Authors: Cutajar Michelle , Braovac Susan , Stockman Robert A. , Howdle Steven M. , Harding Stephen E.
Published: March 2023

The evaluation of two terpene-derived polymers, termed TPA6 and TPA7, as possible consolidants for archaeological wood was carried out. The overall objective of this work was to expand the non-aqueous treatment toolkit which is available for the conservation of the highly degraded Oseberg collection. The wood artefacts which were found on the Oseberg ship were treated with alum in the early twentieth century, leading to the formation of sulfuric acid and to the precarious state that they are in today. Some of these artefacts cannot be treated with conventional aqueous consolidants, like polyethylene glycol, due to their highly degraded and/or reconstructed nature. This study sought to examine the level of penetration of the polymers in archaeological wood and to evaluate their consolidative effect. Both TPA6 and TPA7 were soluble in isopropanol and had a Mw of 3.9 and 4.2 kDa respectively. A number of archaeological wood specimens were immersed in solutions of these polymers. Their penetration and effects were evaluated using weight and dimensional change, colour change, infrared spectroscopy, scanning electron microscopy and hardness tests. Both polymers successfully penetrated the wood specimens, with a higher concentration found on the surface versus the core. Additionally, both polymers appeared to increase the hardness of the specimen surfaces. Increasing the polymer concentration and soaking time in future investigations could potentially facilitate the penetration to the wood cores.
Local environment drives rapid shifts in composition and phylogenetic clustering of seagrass microbiomes
Authors: Kardish Melissa R. , Stachowicz John. J.
Published: March 2023

Plant microbiomes depend on environmental conditions, stochasticity, host species, and genotype identity. Eelgrass (Zostera marina)is a unique system for plant–microbe interactions as a marine angiosperm growing in a physiologically-challenging environment with anoxic sediment, periodic exposure to air at low tide, and fluctuations in water clarity and flow. We tested the influence of host origin versus environment on eelgrass microbiome composition by transplanting 768 plants among four sites within Bodega Harbor, CA. Over three months following transplantation, we sampled microbial communities monthly on leaves and roots and sequenced the V4–V5 region of the 16S rRNA gene to assess community composition. The main driver of leaf and root microbiome composition was destination site; more modest effects of host origin site did not last longer than one month. Community phylogenetic analyses suggested that environmental filtering structures these communities, but the strength and nature of this filtering varies among sites and over time and roots and leaves show opposing gradients in clustering along a temperature gradient. We demonstrate that local environmental differences create rapid shifts in associated microbial community composition with potential functional implications for rapid host acclimation under shifting environmental conditions.
Multi-resonant tessellated anchor-based metasurfaces
Authors: Gallagher Cameron P. , Hamilton Joshua K. , Hooper Ian R. , Sambles J. Roy , Hibbins Alastair P. , Lawrence Christopher R. , Bows John
Published: March 2023

In this work, a multi-resonant metasurface that can be tailored to absorb microwaves at one or more frequencies is explored. Surface shapes based on an ‘anchor’ motif, incorporating hexagonal, square and triangular-shaped resonant elements, are shown to be readily tailorable to provide a targeted range of microwave responses. A metasurface consisting of an etched copper layer, spaced above a ground plane by a thin (< 1/10th of a wavelength) low-loss dielectric is experimentally characterised. The fundamental resonances of each shaped element are exhibited at 4.1 GHz (triangular), 6.1 GHz (square) and 10.1 GHz (hexagonal), providing the potential for single- and multi-frequency absorption across a range that is of interest to the food industry. Reflectivity measurements of the metasurface demonstrate that the three fundamental absorption modes are largely independent of incident polarization as well as both azimuthal and elevation angles.
Assessment of surface and electrical properties of the TiO2@zeolite hybrid materials
Authors: Supelano G. I. , Mesa F. , Vargas C. A. Parra , Gómez J. A. Mejía , Dussan A.
Published: March 2023

Degradation of pollutants in aqueous medium is of high interest due to the impact on environment and human health, therefore, design and study of the physico-chemical properties of photocatalysts for water remediation are of major significance. Among properties of photocatalyst, those related to the surface and electrical mechanism are crucial to the photocatalyst´s performance. Here we report the chemical and morphological characteristics of TiO2@zeolite photocatalyst by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) respectively, and a coherent electrical conduction mechanism was proposed based on data obtained from assisted laser impedance spectroscopy (ALIS), in which the zeolite was synthesized from recycled coal fly ash. The results obtained by SEM and XPS verified the presence of spherical particles of TiO2 anatase with presence of Ti3+ state. ALIS results showed that impedance of the entire system increases when the amount of TiO2 increases and the samples with lower capacitive performance allowed a larger transfer of the charges between the solid–liquid interface. All results showed that higher photocatalytic performance of TiO2 growth over hydroxysodalite with 8.7 wt% and 25 wt% of TiO2 can be explained in terms of the morphology of TiO2 and the interactions between substrate-TiO2 mainly.
Optomechanically induced gain using a trapped interacting Bose-Einstein condensate
Authors: Mikaeili H. , Dalafi A. , Ghanaatshoar M. , Askari B.
Published: March 2023

We investigate the realization of the phenomenon of optomechanically induced gain in a hybrid optomechanical system consisting of an interacting Bose-Einstein condensate trapped inside the optical lattice of a cavity which is generated by an external coupling laser tuned to the red sideband of the cavity. It is shown that the system behaves as an optical transistor while the cavity is exposed to a weak input optical signal which can be amplified considerably in the cavity output if the system is in the unresolved sideband regime. Interestingly, the system has the capability to switch from the resolved to unresolved sideband regime by controlling the s-wave scattering frequency of atomic collisions. We show that the system gain can be enhanced considerably by controlling the s-wave scattering frequency as well as the coupling laser intensity while the system remains in the stable regime. Based on our obtained results, the input signal can be amplified more than 100 million percent in the system output which is much larger than those already reported in the previously proposed similar schemes.
Valorification of Egyptian volcanic tuff as eco-sustainable blended cementitious materials
Authors: Eldahroty Khaled E. H. , Farghali A. A. , Shehata Nabila , Mohamed O. A.
Published: March 2023

Rhyolite rocks extend from southern Egypt to northern Egypt in the Eastern Desert, and no effective economic exploitation of them has been discovered so far. The pozzolanic activities of different volcanic tuffs (VT) supplied from the Eastern Desert located in Egypt have been investigated as natural volcanic pozzolan materials to develop new green cementitious materials for achieving sustainability goals in the construction field. Experimentally in this paper, the pozzolanic activities of seven diverse specimens of Egyptian tuffs taken with standardized proportions of 75:25% (Cement: volcanic tuffs) were investigated. Pozzolanic features of such tuffs are examined comparatively via strength activity index (SAI), TGA, DTA, and the Frattini’s test. Chemical composition, petrographic, and XRD analysis were also performed for tuffs samples. The pozzolanic reaction degrees were determined according to the compressive strengths at 7, 28, 60 and 90 days with different replacement ratios (20, 25, 30 and 40%) of tuffs samples. Additionally, the micro-filler effects in mortar and concrete were determined by measuring the heat of hydration in mortar samples and the compressive strength of concrete with different additive ratios for tuffs samples besides, the concrete slump test. The results show that TF6 gives a lower cement heat of hydration value which is less than 270 J/g at 7 days. Also, its performance in concrete is better than silica fume at late strength (28 days) since the concrete index value is 106.2% by compared to the concrete index of silica fume 103.9 and therefore it can be used as an alternative to high price and quality variable silica fume (SF) for producing high-performance green concrete. Due to the good pozzolanic behavior proved by nearly most volcanic tuffs, along with their low cost, this study will be profitable for very auspicious the use of Egyptian volcanic tuffs for developing sustainable and eco‑friendly blended cement.
Urban economic fitness and complexity from patent data
Authors: Straccamore Matteo , Bruno Matteo , Monechi Bernardo , Loreto Vittorio
Published: March 2023

Over the years, the growing availability of extensive datasets about registered patents allowed researchers to get a deeper insight into the drivers of technological innovation. In this work, we investigate how patents’ technological contents characterise metropolitan areas’ development and how innovation is related to GDP per capita. Exploiting worldwide data from 1980 to 2014, and through network-based techniques that only use information about patents, we identify coherent distinguished groups of metropolitan areas, either clustered in the same geographical area or similar in terms of their economic features. Moreover, we extend the notion of coherent diversification to patent production and show how it is linked to the economic growth of metropolitan areas. Our findings draw a picture in which technological innovation can play a key role in the economic development of urban areas. We contend that the tools introduced in this paper can be used to further explore the interplay between urban growth and technological innovation.
Biomimetic cultivation of atrial tissue slices as novel platform for in-vitro atrial arrhythmia studies
Authors: Amesz Jorik H. , de Groot Natasja M. S. , Langmuur Sanne J. J. , Azzouzi Hamid el , Tiggeloven Vera P. C. , van Rooij Manuela M. M. M. , Knops P. , Bogers Ad J. J. C. , Taverne Yannick J. H. J.
Published: March 2023

Living myocardial slices (LMS) are beating sections of intact human myocardium that maintain 3D microarchitecture and multicellularity, thereby overcoming most limitations of conventional myocardial cell cultures. We introduce a novel method to produce LMS from human atria and apply pacing modalities to bridge the gap between in-vitro and in-vivo atrial arrhythmia studies. Human atrial biopsies from 15 patients undergoing cardiac surgery were dissected to tissue blocks of ~ 1 cm2 and cut to 300 µm thin LMS with a precision-cutting vibratome. LMS were placed in a biomimetic cultivation chamber, filled with standard cell culture medium, under diastolic preload (1 mN) and continuous electrical stimulation (1000 ms cycle length (CL)), resulting in 68 beating LMS. Atrial LMS refractory period was determined at 192 ± 26 ms. Fixed rate pacing with a CL of 333 ms was applied as atrial tachyarrhythmia (AT) model. This novel state-of-the-art platform for AT research can be used to investigate arrhythmia mechanisms and test novel therapies.
Building social capital with elders’ leadership through a community hub “Ibasho” in the Philippines and Nepal
Authors: Aida Takeshi , Kiyota Emi , Tanaka Yasuhiro , Sawada Yasuyuki
Published: March 2023

We quantitatively study the Ibasho project—a unique, innovative community-based project that involves co-creating a building as a social hub. Ibasho’s decision-making undertakes a bottom-up approach, differentiating itself from the conventional top-down decision-making process. Using sui generis data, we find that Ibasho projects in the Philippines and Nepal contributed to enhancing social capital among elders in both cases. Yet there are differences between the two communities. In the Philippines, participation in Ibasho increased the number of a participant’s friends, or “strong ties,” indicating that it is on the intensive margin of human relationships. In contrast, joining Nepal’s Ibasho broadened weak ties rather than strong ones. This contrast may stem from the difference in pre-existing social and built infrastructures in the two communities, which were strengthened through the building-human interactions.
Strong temporal variation of consumer δ13C value in an oligotrophic reservoir is related to water level fluctuation
Authors: Veselý Lukáš , Ercoli Fabio , Ruokonen Timo J. , Bláha Martin , Duras Jindřich , Haubrock Phillip J. , Kainz Martin , Hämäläinen Heikki , Buřič Miloš , Kouba Antonín
Published: March 2023

Using stable carbon and nitrogen isotope analysis (δ13C and δ15N) to assess trophic interactions in freshwater ecosystems is a well established method, providing insight into ecosystem functioning. However, the spatial and temporal variability of isotope values, driven by environmental fluctuation is poorly understood and can complicate interpretations. We investigated how the temporal variation of stable isotopes in consumers (fish, crayfish and macrozoobenthos) of a canyon-shaped oligotrophic reservoir is associated with environmental factors such as water temperature, transparency, flooded area, and water quality measures. Consumers and their putative food sources were sampled and analyzed for carbon and nitrogen stable isotopes annually, and environmental parameters were measured monthly from 2014 to 2016. Results revealed significant differences in δ13C and δ15N values in each consumer among studied years. Over the years, fish and crayfish expressed differences in δ13C between 3 and 5‰, whereas in zoobenthos differences were 12‰. Variability in δ15N was similar across all consumers (2–4‰). Moreover, results suggest that the flooded area of the reservoir was a major driver of δ13C stable isotope values variation in consumers, while variation in δ15N was not linked to any of the studied environmental factors. Bayesian mixing models further showed significant changes in the origin of detritivorous zoobenthos carbon sources (reversal shift from terrestrial detritus to algae origin) between years with low water level to years with the standard water level. Other species showed only slight differences in food source utilization among years. Our study highlights the importance of environmental factors as sources of variation in consumer’s stable isotope values which should be considered especially when studied ecosystem strongly fluctuate in some environmental factor.
Recycling micro polypropylene in modified hot asphalt mixture
Authors: Buruiana Daniela Laura , Georgescu Puiu Lucian , Carp Gabriel Bogdan , Ghisman Viorica
Published: March 2023

One of the objectives of the circular economy is solving the world’s plastic pollution crisis and recycling of materials by ensuring less waste. The motivation of this study was to demonstrate the possibility of recycling two types of wastes with a high risk of pollution, such as plastic based polypropylene and abrasive blasting grit wastes in asphalt roads. The effects of adding together polypropylene based microplastics and grit waste in asphalt mixture for wear layer performance have been shown in this study. The morphology and elemental composition of the hot asphalt mixture samples before and after freeze–thaw cycle were examined by SEM–EDX and the performance of the modified asphalt mixture was determined with laboratory tests including Marshall stability, flow rate, solid–liquid report, apparent density, and water absorption. A hot asphalt mixture suitable for making wear layer in road construction, containing aggregates, filler, bitumen, abrasive blasting grit waste and polypropylene based microplastics is also disclosed. In the recipe of modified hot asphalt mixtures were added 3 proportions of polypropylene-based microplastics such as 0.1%, 0.3% and 0.6%. An improvement of the mixture performance is shown at the asphalt mixture sample with 0.3% of polypropylene. In addition, polypropylene-based microplastics are bond with aggregates from mixture well, so the polypropylene-modified hot asphalt mixture can effectively decrease the appearance of cracks during sudden temperature changes.
The deep origin of ground fissures in the Kenya Rift Valley
Authors: Jia Zhijie , Wu Hongjie , Peng Jianbing , Lu Quanzhong , Huang Weiliang , Liu Chuntao , Wang Feiyong , Liu Yang , He Ming
Published: March 2023

Intense volcanic and geothermal activities characterize the Great Rift Valley of East Africa. Ground fissure disasters of the Great Rift Valley have garnered increasing attention in recent years. Through field investigations, trenching, geophysical exploration, gas sampling and analysis, we determined the distribution and origin of 22 ground fissures within the Kedong Basin of the Central Kenya Rift. These ground fissures caused varying degrees of damage to roads, culverts, railways, and communities. Trenching and geophysical exploration have shown that ground fissures in sediments are connected to rock fractures with gas escaping. The gases expelled from the rock fractures contained methane and SO2, which were absent in the normal atmosphere, and 3He/4He ratios in gases measured further indicated that the volatiles were derived from the mantle, suggesting that these rock fractures extended deep into the underlying bedrock. Spatial correlations with rock fractures demonstrate the deep origin of these ground fissures, which are associated with active rifting, plate separation, and volcanism. The ground fissures are formed due to movement on the deeper rock fractures, and then the gas escapes through the fissures. Determining the unusual origin of these ground fissures can not only guide infrastructure development and urban planning but also contribute to the safety of local communities.
Comparison between three types of needles for endoscopic ultrasound-guided tissue acquisition of pancreatic solid masses: a multicenter observational study
Authors: Yang Min Jae , Kim Jaihwan , Park Se Woo , Cho Jae Hee , Kim Eui Joo , Lee Yun Nah , Lee Dong Wook , Park Chan Hyuk , Lee Sang Soo
Published: March 2023

It is debatable which needle has clear superiority of diagnostic performance in endoscopic ultrasound (EUS)-guided fine needle biopsy (FNB) of solid pancreatic masses. This study aimed to compare the performance of three needles and determine the variables that affect diagnostic accuracy. From March 2014 to May 2020, 746 patients with solid pancreatic masses who underwent EUS-FNB using three types of needles (Franseen needle, Menghini-tip needle, and Reverse-bevel needle) were retrospectively reviewed. Multivariate analysis using a logistic regression model was used to identify factors related to diagnostic accuracy. There were significant differences between the groups regarding the procurement rate of the histologic and optimal quality cores (Franseen vs. Menghini-tip vs. Reverse-bevel: 98.0% [192/196] vs. 85.8% [97/113] vs. 91.9% [331/360], P < 0.001 and 95.4% [187/196] vs. 65.5% [74/113] vs. 88.3% [318/360], P < 0.001, respectively). The sensitivity and accuracy using histologic samples were 95.03% and 95.92% for Franseen, 82.67% and 88.50% for Menghini-tip, and 82.61% and 85.56% for Reverse-bevel needles, respectively. In direct comparison between the needles using histologic samples, the Franseen needle showed significantly superior accuracy than the Menghini-tip (P = 0.018) and Reverse-bevel needles (P < 0.001). Multivariate analysis indicated that tumor size ≥ 2 cm (odds ratio [OR] 5.36, 95% confidence interval [CI] 3.40–8.47, P < 0.001) and fanning technique (OR 1.70, 95% CI 1.00–2.86, P = 0.047) were significantly associated with an accurate diagnosis. EUS-FNB using the Franseen needle enables the acquisition of a larger and more adequate histologic core tissue and achieves an accurate histological diagnosis when using the fanning technique.
Smartphone videos of the sit-to-stand test predict osteoarthritis and health outcomes in a nationwide study
Authors: Boswell Melissa A. , Kidziński Łukasz , Hicks Jennifer L. , Uhlrich Scott D. , Falisse Antoine , Delp Scott L.
Published: March 2023

Physical function decline due to aging or disease can be assessed with quantitative motion analysis, but this currently requires expensive laboratory equipment. We introduce a self-guided quantitative motion analysis of the widely used five-repetition sit-to-stand test using a smartphone. Across 35 US states, 405 participants recorded a video performing the test in their homes. We found that the quantitative movement parameters extracted from the smartphone videos were related to a diagnosis of osteoarthritis, physical and mental health, body mass index, age, and ethnicity and race. Our findings demonstrate that at-home movement analysis goes beyond established clinical metrics to provide objective and inexpensive digital outcome metrics for nationwide studies.
C. elegans is not a robust model organism for the magnetic sense
Authors: Malkemper Erich Pascal , Pikulik Patrycja , Krause Tim Luca , Liu Jun , Zhang Li , Hamauei Brittany , Scholz Monika
Published: March 2023

Magnetoreception is defined as the ability to sense and use the Earth’s magnetic field, for example to orient and direct movements. The receptors and sensory mechanisms underlying behavioral responses to magnetic fields remain unclear. A previous study described magnetoreception in the nematode Caenorhabditis elegans, which requires the activity of a single pair of sensory neurons. These results suggest C. elegans as a tractable model organism for facilitating the search for magnetoreceptors and signaling pathways. The finding is controversial, however, as an attempt to replicate the experiment in a different laboratory was unsuccessful. We here independently test the magnetic sense of C. elegans, closely replicating the assays developed in the original publication. We find that C. elegans show no directional preference in magnetic fields of both natural and higher intensity, suggesting that magnetotactic behavior in the worm is not robustly evoked in a laboratory setting. Given the lack of a robust magnetic response under controlled conditions, we conclude that C. elegans is not a suitable model organism to study the mechanism of the magnetic sense.
Verification of preparations of (1H-indol-3-yl)methyl electrophiles and development of their microflow rapid generation and substitution
Authors: Masui Hisashi , Kanda Sena , Fuse Shinichiro
Published: March 2023

Although highly reactive (1H-indol-3-yl)methyl electrophiles such as (1H-indol-3-yl)methyl halides are potential precursors for the synthesis of various indole derivatives, some researchers have reported difficulties in their preparation due to concomitant undesired dimerization/oligomerization. Nevertheless, there have been some reports on the preparation of (1H-indol-3-yl)methyl halides. To resolve this contradiction, all the previously reported preparations of (1H-indol-3-yl)methyl halides were examined. However, we could not reproduce any of these preparations, and we revised several structures of indole derivatives. Here we show the rapid (0.02 s) and mild (25 °C) generation of an (1H-indol-3-yl)methyl electrophile that enables the rapid (0.1 s) and mild (25 °C) nucleophilic substitution in a microflow reactor. Eighteen unprotected indole analogues can be successfully synthesized using the developed microflow nucleophilic substitution with various nucleophiles.
Self-cyclisation as a general and efficient platform for peptide and protein macrocyclisation
Authors: Jia Xinying , Chin Yanni K.-Y. , Zhang Alan H. , Crawford Theo , Zhu Yifei , Fletcher Nicholas L. , Zhou Zihan , Hamilton Brett R. , Stroet Martin , Thurecht Kristofer J. , Mobli Mehdi
Published: March 2023

Macrocyclisation of proteins and peptides results in a remarkable increase in structural stability, making cyclic peptides and proteins of great interest in drug discovery—either directly as drug leads or as in the case of cyclised nanodiscs (cNDs), as tools for studies of trans-membrane receptors and membrane-active peptides. Various biological methods have been developed that are capable of yielding head-to-tail macrocyclised products. Recent advances in enzyme-catalysed macrocyclisation include discovery of new enzymes or design of new engineered enzymes. Here, we describe the engineering of a self-cyclising “autocyclase” protein, capable of performing a controllable unimolecular reaction for generation of cyclic biomolecules in high yield. We characterise the self-cyclisation reaction mechanism, and demonstrate how the unimolecular reaction path provides alternative avenues for addressing existing challenges in enzymatic cyclisation. We use the method to produce several notable cyclic peptides and proteins, demonstrating how autocyclases offer a simple, alternative way to access a vast diversity of macrocyclic biomolecules.
Preclassic environmental degradation of Lake Petén Itzá, Guatemala, by the early Maya of Nixtun-Ch’ich’
Authors: Birkett Brooke A. , Obrist-Farner Jonathan , Rice Prudence M. , Parker Wesley G. , Douglas Peter M. J. , Berke Melissa A. , Taylor Audrey K. , Curtis Jason H. , Keenan Benjamin
Published: March 2023

Paleolimnological evidence indicates the ancient Maya transformed terrestrial ecosystems by felling forest vegetation to construct large civic-ceremonial centers and to expand agriculture. Human settlements influenced lacustrine environments but the effects of Maya activities on aquatic ecosystems remain poorly studied. Here we analyzed a sediment core from Lake Petén Itzá, Guatemala, to infer paleoenvironmental changes resulting from Maya occupation of the archaeological site of Nixtun-Ch’ich’. Increases in charcoal and fecal stanol concentrations indicate Maya occupation of the Candelaria Peninsula by the late Early Preclassic period. Geochemical proxies reveal a period of lake ecosystem alteration during construction and expansion of the city’s urban grid in the Middle and Late Preclassic periods. Depopulation of the city in the Terminal Preclassic resulted in a decline in lake trophic state. Whereas previous studies of Petén waterbodies have indicated depressed lacustrine primary production, the core collected near Nixtun-Ch’ich’ shows evidence of ancient Maya lake ecosystem deterioration.
Preventing comorbidity between distress and suicidality: a network analysis
Authors: Junus Alvin , Yip Paul S. F.
Published: March 2023

Suicidality among individuals between 10 and 35 years of age may be poised to exert massive burdens on society through decreased economic productivity and increased incidence of chronic physical conditions in the individuals’ later years, thereby necessitating early prevention of suicide. While research suggests that the pathway to suicidality may begin from episodes of psychological distress, such pathway may involve complex interplays between intermediary psychiatric symptoms and external stimuli that are not easily delineated through conventional means. This study applies the network approach to psychopathology to elucidate this complexity. Comorbidity between psychological distress and suicidality in 1968 community-dwelling individuals is analyzed with regularized partial correlation networks to identify their bridge symptoms and links. Temporal relationships between symptoms are analyzed through temporal symptom network formed from 453 individuals who completed subsequent follow-up surveys. Network analysis shows that feelings of hopelessness and the presence of suicidal ideation are the strongest bridge symptoms in the comorbidity symptom network, and form the only prominent link that bridges psychological distress and suicidality. Effects of sleep troubles, anxiety, and poor social relationships on suicidal ideation appear to be mediated by hopelessness. The same observations hold among individuals with and without diagnoses of psychiatric disorders, as well as young people (10–24 year-olds) and young adults (25–35 year-olds). The edge between hopelessness and suicidal ideation remains the strongest bridge link after controlling for effects of symptoms from the previous time point. Findings here provide an evidence base for both professional training in caregiving professions as well as gatekeeper training in community members to emphasize more on how to effectively recognize hopelessness, and instill hope, in young people and young adults for various types of distress.
On the origin of the combinatorial complexity of the crystal structures with 0D, 1D, or 2D primary motifs
Authors: Banaru Daria A. , Hornfeck Wolfgang , Aksenov Sergey M. , Banaru Alexander M.
Published: March 2023

Based on Krivovichev information measures for crystal structures and the universal partitioning scheme for different sources of information described previously by Hornfeck, we proposed a general scheme of complexity calculation for heterodesmic crystals.
Machine learning and density functional theory simulation of the electronic structural properties for novel quaternary semiconductors
Authors: Gao Mengwei , Cai Bo , Liu Gaoyu , Xu Lili , Zhang Shengli , Zeng Haibo
Published: March 2023

Four quaternary semiconductors with excellent properties as candidate luminescent materials are selected by combining machine learning and first-principles calculations.
Pharmacodynamic structure of deer antler base protein and its mammary gland hyperplasia inhibition mechanism by mediating Raf-1/MEK/ERK signaling pathway activation
Authors: Sun Shiqing , Zhang Kai , Wang Yuliang , Zhou Zijun , Wang Lihong , Zhao Hong , Zhang Yu
Published: March 2023

Deer antler base protein regulate the sex hormonal levels, improve the mammary gland histopathological condition, andviamediating the Raf-1/MEK/ERK signaling pathway achieve Mammary gland hyperplasia (MGH) inhibition.
Nanomedicine strategies to improve therapeutic agents for the prevention and treatment of preterm birth and future directions
Authors: Taylor Jessica , Sharp Andrew , Rannard Steve P. , Arrowsmith Sarah , McDonald Tom O.
Published: March 2023

This review outlines the importance of improving the treatment of preterm birth, summarises the use of nanomedicines for the delivery of active pharmaceutical ingredients and discusses the opportunities/challenges for enhancing future patient outcomes.
High-performance adhesives modified by demethylated lignin for use in extreme environments
Authors: Zhang Shuang , Zhao Xin , Chen Pengchao , Sun Guangwei , Li Yao , Han Ying , Wang Xing , Li Jigeng
Published: March 2023

Lignin-modified epoxy resin (LER) is a promising alternative to bisphenol A in the preparation of epoxy resins.
Photochemical difluoromethylation of alkynes: synthesis of CF2H-substituted seven-membered dioxodibenzothiazepines and dibenzazepines
Authors: Chen Xiaoyu , Geng Yang , Liu Bo , Zhu Yu , Zou Dapeng , Wu Yangjie , Wu Yusheng
Published: March 2023

A general and efficient photochemical strategy for difluoromethylation/radical cascade cyclization of alkynes with sodium difluoromethylsulfinate (NaSO2CF2H) has been disclosed.
A review on learning to solve combinatorial optimisation problems in manufacturing
Authors: Zhang Cong , Wu Yaoxin , Ma Yining , Song Wen , Le Zhang , Cao Zhiguang , Zhang Jie
Published: March 2023

An efficient manufacturing system is key to maintaining a healthy economy today. With the rapid development of science and technology and the progress of human society, the modern manufacturing system is becoming increasingly complex, posing new challenges to both academia and industry. Ever since the beginning of industrialisation, leaps in manufacturing technology have always accompanied technological breakthroughs from other fields, for example, mechanics, physics, and computational science. Recently, machine learning (ML) technology, one of the crucial subjects of artificial intelligence, has made remarkable progress in many areas. This study thoroughly reviews how ML, specifically deep (reinforcement) learning, motivates new ideas for addressing challenging problems in manufacturing systems. We collect the literature targeting three aspects: scheduling, packing, and routing, which correspond to three pivotal cooperative production links of today's manufacturing system, that is, production, packing, and logistics respectively. For each aspect, we first present and discuss the state‐of‐the‐art research. Then we summarise and analyse the development trends and point out future research opportunities and challenges.
A dual‐balanced network for long‐tail distribution object detection
Authors: Gong Huiyun , Li Yeguang , Dong Jian
Published: March 2023

Object detection on datasets with imbalanced distributions (i.e. long‐tail distributions) dataset is a significantly challenging task. Some re‐balancing solutions, such as re‐weighting and re‐sampling have two main disadvantages. First, re‐balancing strategies only utilise a coarse‐grained global threshold to suppress some of the most influential categories, while overlooking locally influential categories. Second, very few studies have specifically designed algorithms for object detection tasks under long‐tail distribution. To address these two issues, a dual‐balanced network for fine‐grained re‐balancing object detection is proposed. Our re‐balancing strategies are both in proposal and classification logic, corresponding to two sub‐networks, the Balance Region Proposal Network (BRPN) and the Balance Classification Network (BCN). The BRPN sub‐network equalises the number of proposals in the background and foreground by reducing the sampling probability of simple backgrounds, and the BCN sub‐network equalises the logic between head and tail categories by globally suppressing negative gradients and locally fixing the over‐suppressed negative gradients. In addition, the authors advise a balance binary cross entropy loss to jointly re‐balance the entire network. This design can be generalised to different two‐stage object detection frameworks. The experimental mAP result of 26.40% on this LVIS‐v0.5 dataset outperforms most SOTA methods.
Selective feature fusion network for salient object detection
Authors: Sun Fengming , Yuan Xia , Zhao Chunxia
Published: March 2023

Fully convolutional neural networks have achieved great success in salient object detection, in which the effective use of multi‐layer features plays a critical role. Based on this advantage, many saliency detectors have emerged in recent years, and most of them designed a series of network structures to integrate the multi‐level features generated by the backbone network. However, information in different layer play different roles in saliency object detection, how to integrate them effectively is still a great challenge. In this article, a selective feature fusion network which consists of a selective feature fusion module (SFM) and an attention‐guide hierarchical feature emphasis module (AEM) is proposed. Most of the previous works mainly integrate multi‐level feature by addition and concatenation, as a difference, SFM adaptively selects the important information from the input features in the fusion, which effectively avoids introducing too much redundant information. Besides, AEM combines spatial attention and channel attention to enhance features simply and effectively by hierarchical iteration, and further improve the accuracy of salient object detection. Experiments on five datasets show that the proposed selective feature fusion method achieve satisfactory results when comparing to other state‐of‐the‐art salient object detection approaches.
Review of condition monitoring and defect inspection methods for composited cable terminals
Authors: Li Shuaibing , Cao Binglei , Li Jin , Cui Yi , Kang Yongqiang , Wu Guangning
Published: March 2023

Composited cable terminals are critical for reliable power delivery of traditional and traction power supply systems. During its operation, the cable terminal continually undergoes complex circumstances where humidity, temperature, field strength, mechanical stress and other factors continuously change at different levels. In extreme cases, defects or even failures may occur in the cable terminals, leading to catastrophic accidents. This makes the condition monitoring and defect detection of composited cable terminals become an imperative need for the power industry. The “state‐of‐the‐art” technology of cable terminal condition assessment is focussed and a systematic review of the current research progress of cable terminal condition assessment from the operation circumstances to failure mechanisms is provided. It covers both online/offline condition monitoring methods and defects detection approaches. In addition, challenges and future research directions for cable terminal condition assessment are also addressed. It is concluded that the non‐destructive and non‐intrusive methods like terahertz imaging and ultrasonic testing, and multi‐source information fusion methods as well as the digital twin technology have been gaining popularity for cable terminal defect inspection. It is expected the presented work can provide a global field of vision for further advancement of both scholars and industrial engineers in this field.
Design of 3D stacked wideband Wilkinson power divider based on rectangular micro‐coaxial process
Authors: Xu Li‐Jie , Xu Lang , Zhang Cong‐Tian , Wu Wen‐Jie , Zhang Hong‐Lin , Lyu Yunpeng , Li Bo
Published: March 2023

Based on transmission line theory, a 4‐way wideband coupled‐line Wilkinson power divider is designed by the authors, operating from 6 to 18 GHz. It is established by using a novel manufacturing technology with 3D stacked micro‐coaxial line, realising attractive advantages of low insertion (IL) loss and compact size. The simulated result shows that the proposed power divider of 23.5 × 14.46 × 0.9 mm obtains a maximum IL of 0.42 dB over the entire operating band. Measured results are obtained by connecting this micro‐coaxial power divider with printed circuit board, showing that the proposed structure is suitable for microwave communication systems.
A new clustering‐based optimised energy approach for fog‐enabled IoT networks
Authors: Essalhi Salah Eddine , Raiss El Fenni Mohammed , Chafnaji Houda
Published: March 2023

The Internet of Things (IoT) has induced many advances in the modern world, thus always arousing great interest from the scientific community. Due to a large number of connected devices, this paradigm has put into circulation an enormous data quantity to be processed and offloaded while respecting latency and energy constraints that Central Cloud alone cannot meet. Hence, Fog Computing has come to fill these gaps by providing computing, management, and storage resources via small‐distributed data centres located at the network edge. The majority of previous research on centralised clustering in an IoT environment did not consider both residual energy and the location of the IoT devices, as well as the signalling communication frequency, to solve an issue of extreme energy consumption during data exchange between IoT devices and Fog entities. Thus, the objective of this study is to find solutions taking into account these criteria to guarantee the Fog system's energy efficiency while coping with the energy consumption increase related to the handling of massive data volume. Indeed, the proposed study presents a novel approach based on Fog‐IoT architecture to ensure intelligent energy management during communication and offloaded task processing in IoT applications. The simulation results show its effectiveness.
A power switch open‐circuit fault‐tolerant scheme using dc current injection for dual active bridge converters in cascaded h‐bridge solid‐state transformer
Authors: Zang Jiajie , Wang Jiacheng , Zhang Jianwen , Zhou Jianqiao , Shi Gang , Feng Xin , Zhang Yixin
Published: March 2023

Due to its excellent modularity and scalability, the cascaded H‐bridge solid‐state transformer (CHB SST) is a prominent candidate for interconnecting different grids in future hybrid ac/dc distribution systems. However, the CHB SST's large number of power switches are potential sources of faults that can disrupt the system's normal operation. Among other failure modes, a power switch open‐circuit fault (OCF) in a dual active bridge (DAB) module in the SST can result in overcurrent and previously ignored DAB high‐frequency transformer (HFT) saturation issues. The fault is generally addressed by installing redundant modules or additional devices, which would increase the cost, size, and complexity of the system. Based on the OCF analysis presented in this paper, a fault‐tolerant scheme using dc current injection and phase shift ratio adjustment is proposed to maintain the CHB SST operation with maximum remaining bidirectional power transfer capability of the faulty DAB. The overcurrent and HFT saturation issues are also eliminated. The proposed scheme features less cost and volume as compared with module redundancy methods. Moreover, it does not require modifications in the configuration and implementation of the SST. The feasibility and effectiveness of the proposed scheme are verified through a 4.8 kVA CHB SST experimental platform.