bluuebunny/crossref_metadata_2025 huggingface dataset:
On the relationship between western North Pacific tropical cyclone accumulated cyclone energy and the Pacific‐North American pattern
Authors: Song Jinjie , Klotzbach Philip J. , Duan Yihong
Published: February 2022

This study investigates the influence of the Pacific‐North American (PNA) pattern on the accumulated cyclone energy (ACE) of tropical cyclones (TCs) over the western North Pacific (WNP). There is a significant inverse relationship between ACE during July–October and the simultaneous PNA index during 1970–2020. Lower (greater) basinwide ACE is observed when the PNA is positive (negative), primarily as a result of lesser (greater) TC frequency, while the effects of duration and intensity are found to be relatively minor. When examining the results spatially, we find lower ACE over almost the entire WNP when the PNA index is positive compared with when the PNA is negative. Significant decreases in ACE are observed over the region to the north and east of Guam (10°–35°N, 135°–165°E) and near the Philippines (10°–25°N, 110°–130°E). These decreases when the PNA is positive are primarily induced by a decrease in TC formation as well as a reduction in average intensity in a region north and east of Guam, possibly linked to decreased low‐level vorticity and upper‐level divergence as well as increased vertical wind shear. These changes in dynamic variables are predominantly driven by large‐scale flow patterns related to the PNA.
Complement component 3 and its activation split‐products in saliva associate with periodontitis
Authors: Damgaard Christian , Massarenti Laura , Danielsen Anne Katrine , Graversen Jonas H. , Holmstrup Palle , Nielsen Claus H. , Palarasah Yaseelan
Published: February 2022

Background

Periodontitis (PD) is classified by Grades A through C according to the risk of further progression, PD Grade C (PD‐C) being the most severe progressing form. It is a matter of controversy, whether the disease activity observed in PD‐C is due to impaired immune reactivity toward bacteria embedded in biofilms or a hyper‐reactive immune response causing tissue damage as a bystander phenomenon. Little is known about the role of complement in this respect.

Methods

Plasma and unstimulated saliva samples were collected from patients with PD‐B (n = 34) or ‐C (n = 27) and healthy controls (HCs) (n = 28). Salivary and plasma levels of total C3, C3c, and C3dg were quantified using sandwich enzyme‐linked immunosorbent assay (ELISA).

Results

Salivary levels of total C3 and C3dg were elevated in PD‐B and PD‐C patients compared to HCs (both P < 0.05), while the levels of C3c were elevated in PD‐C compared to HCs. Plasma levels of C3c were higher in PD‐B patients than in HCs (P < 0.05).

Conclusion

PD‐B and PD‐C patients show increased complement activation compared to HCs, but no difference was found between the two disease grades. PD‐B, but not PD‐C, is associated with increased systemic complement activation as assessed by C3c in plasma.
Genetic variation in skin traits in New Zealand lambs
Authors: McRae Kathryn M , Cooper Sue M , McEwan John C , Anderson Rayna , Bain Wendy E , Baird Hayley J , Dodds Ken G , Clarke Shannon M , Pickering Natalie K , Holmes Geoff
Published: March 2022

BACKGROUND

This study explored the genetic variability in the New Zealand sheep population for economically important skin traits. Skins were collected at slaughter from two progeny test flocks, resulting in 725 skins evaluated for grain strain, flatness, crust leather strength and overall suitability for shoe leather. DNA profiles collected from skins post‐slaughter were matched to individual animals using previously collected high‐density genotypes.

RESULTS

Considerable phenotypic variation for skin traits was observed, with around 40% of the skins being identified as suitable for high‐value shoe leather production. Several key traits associated with leather production, including flatness, tear strength, grain strength and grain strain were found to be moderate to highly heritable (h2 = 0.28–0.82).

There were no major significant genome‐wide association study (GWAS) peaks associated with many of the traits examined, however, one single‐nucleotide polymorphism (SNP) reached significance for the flatness of the skin over the hindquarters.

CONCLUSION

This research confirms that suitable lamb skins can be bred for use as high‐value shoe leather. While moderately to highly heritable, skin traits in New Zealand lambs appear to be polygenic with no genes of major effect underlaying the traits of interest. Given the complex nature of these traits, the identification and selection of animals with higher‐value skins may be enabled by geomic selection. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
Feasibility and effectiveness of opioid‐free anesthesia in cytoreductive surgery with or without heated intraperitoneal chemotherapy
Authors: Tejedor Ana , Bijelic Lana , Deiros Carmen , Pujol Elisenda , Bassas Eva , Fernanz Jesús , Bernat Maria José
Published: February 2022

Background

Opioid‐free anesthesia (OFA) provides analgesia minimizing opioids. OFA has not been evaluated in cytoreductive surgery (CRS) with or without heated intraperitoneal chemotherapy. We aim to evaluate OFA feasibility and effectiveness in CRS.

Methods

Retrospective cohort study of adult patients (84) undergoing CRS in a tertiary center from May 2020 until June 2021. Predefined protocols for either opioid‐based anesthesia (OBA) or OFA were followed.

Results

OFA protocol patients (41) had better mean pain scores (1 ± 0.8 vs. 2 ± 1; p = 0.00) despite the avoidance of intravenous and epidural fentanyl intraoperatively (220 ± 104 and 194 ± 73 µg, respectively, in OBA vs. 0; p = 0.00). Postoperative epidural levobupivacaine was also lower in the OFA group (575 ± 192 vs. 706 ± 346 mg; p = 0.034) despite the lack of epidural fentanyl without difference in duration (4.3 ± 1.2 vs. 4 ± 1.2 days; p = 0.22). Morphine consumption was very low (4.1 ± 10 vs. 1.7 ± 5 mg; p = 0.16). Intraoperative hypertensive events and postoperative nausea and vomiting (PONV) were higher for OBA (43) (30.2% vs. 7.3%; p = 0.01% and 69.8% vs. 34.1%; p = 0.001, respectively). Postoperative epidural fentanyl was independently associated with PONV (p = 0.004). There was no difference in total complications or length of stay.

Conclusion

OFA is feasible, safe, and offers optimal pain control while minimizing the use of opioids in CRS.
Amino functionalized magnetic covalent organic framework for magnetic solid‐phase extraction of sulfonylurea herbicides in environmental samples from tobacco land
Authors: Tian Cong , Wu Zhekuan , He Man , Chen Beibei , Hu Bin
Published: February 2022

An amino‐functionalized magnetic covalent organic framework composite TpBD‐(NH2)2@Fe3O4 (Tp=Tp1,3,5‐triformylphloroglucinol, BD‐(NH2)2 is 3,3',4,4'‐biphenyltetramine) was prepared by post‐synthesis modification. Due to its abundant benzene rings and amino groups, large specific surface area and porous structure, the prepared TpBD‐(NH2)2@Fe3O4 exhibits high extraction efficiency toward sulfonylurea herbicides. Based on this, a new method of magnetic solid‐phase extraction with TpBD‐(NH2)2@Fe3O4 as the sorbent combined with high‐performance liquid chromatography and ultraviolet detection was developed for trace analysis of sulfonylurea herbicides in environmental water, soil and tobacco leaves samples from tobacco land. Under the optimized conditions, the limits of detection within 0.05–0.14 μg/L were achieved with a high enrichment factor of 217‐260‐fold, and the relative standard deviations were 4.9–7.5% (n = 7, c = 0.5 μg/L). The linear range was around three orders of magnitude with the square of correlation coefficient higher than 0.9936. The method was applied to analyze five sulfonylurea herbicides in the environmental water, soil, and tobacco leave samples collected from tobacco land. No sulfonylurea herbicides were detected in these samples. The recoveries of target sulfonylurea herbicides in spiked environmental water, soil, and tobacco leaf samples were found in the range of 90.7–104, 70.7–99.0, and 59.3–97.8%, respectively. The results illustrate that the established TpBD‐(NH2)2@Fe3O4‐magnetic solid‐phase extraction‐ high‐performance liquid chromatography–ultraviolet detection method is efficient for the analysis of trace sulfonylurea herbicides in environmental samples.
Measurement of microplastic settling velocities and implications for residence times in thermally stratified lakes
Authors: Elagami Hassan , Ahmadi Pouyan , Fleckenstein Jan H. , Frei Sven , Obst Martin , Agarwal Seema , Gilfedder Benjamin S.
Published: February 2022

Microplastics residence times in lakes are currently poorly understood. In this work, settling experiments with pristine and biofilm‐colonized microplastic particles were combined with model calculations to evaluate settling velocities, particle distributions, and residence times in the epilimnion, metalimnion, and hypolimnion of a hypothetical stratified lake broadly based on Upper Lake Constance. Settling velocities of various biodegradable and nonbiodegradable polymers of various shapes, sizes, and biofilm colonization were measured in a settling column. The settling velocities ranged between ~ 0.30 and ~ 50 mm s−1. Particle sizes and polymer densities were identified as primary controls on settling rates. Microplastic particles that had been exposed to a lake environment for up to 30 weeks were colonized by a range of biofilms and associated extracellular polymeric substances; surprisingly, however, the settling velocity did not vary significantly between pristine and colonized microplastic particles. Simulated microplastic residence times in the model lake varied over a wide range of time scales (10−1 to 105 d) and depended mainly on the size of the particles and depth of the lake layer. Long residence times on the order of 105 d (for 1‐μm microplastic particles) imply that for small microplastic particles there is a high probability that they will be taken up at some stage by lake organisms. As the lake retention time (~ 4.5 years) is considerably shorter than the residence time of small microplastics, negligible quantities of these microplastic particles should be found in the lake sediment unless some other process increases their settling velocity.
Corrosion resistance of iron‐containing experimental titanium alloys exposed to simulated body fluids
Authors: Leshetla Mogomotsi , Klenam Desmond E. , van der Merwe Josias , Potgieter Herman , Whitefield David , Bodunrin Michael O.
Published: February 2022

In this study, experimental Ti–6Al–1V–3Fe, Ti–4.5Al–1V–3Fe, and Ti–3Fe alloys, as well as commercial Ti–6Al–4V alloy that were scaled up utilizing vacuum induction melting technology, were assessed for corrosion performance in simulated body fluids. The selected simulated body fluids were 0.9 wt% NaCl solution and Hanks balanced salt solution (HBSS). Open circuit potential and linear polarization scans were performed to understand the corrosion performance of the alloys. The surface of the alloys was examined before and after exposure to corrosive solutions using scanning electron microscopy. The results show that all the alloys exhibit good corrosion performance in simulated body fluids. The corrosion rates were less than 0.5 mm/year. Owing to higher corrosion potential and lower corrosion rate, Ti–6Al–1V–3Fe and Ti–4.5Al–1V–3Fe had the best resistance to corrosion in 0.9 wt% NaCl and HBSS, respectively. All the alloys consist of a fully lamellar structure with α and β phases. There was no evidence of severe deterioration on the exposed surface of alloys in the simulated body fluids.
Lithium Salt‐Induced In Situ Polymerizations Enable Double Network Polymer Electrolytes
Authors: Zhang Chi , Jiang Ke , Zhang Yong , Wang Jirong , Xue Zhigang
Published: February 2022

Structural design is an intriguing strategy to improve the physical and electrochemical performance of polymer electrolytes (PEs) for lithium‐ion batteries. However, the complex synthetic process and introduction of nonelectrolyte composition severely limit the development and practical application of PEs. Here, a facile method is reported for the fabrication of a double network polymer electrolyte (DN‐PE) through combining the lithium salt‐accelerated thiol‐Michael addition and lithium salt‐catalyzed radical polymerization. By adjusting the reaction temperature, the double network with the cross‐linking structure can be in situ formed step by step at room temperature and 80 °C. Notably, using lithium salt as the accelerator and catalyst avoids the addition of extra species and the related side reactions in the electrolyte system. Compared with single network polymer electrolyte (SN‐PE), DN‐PE has a distinctly improved mechanical strength and a better interfacial compatibility with the electrode, which leads to a stable cycling of the symmetric Li|DN‐PE|Li cell over 1000 h at a current density of 0.05 mA cm–2. In addition, the Li|DN‐PE|LiFePO4 cell shows a high discharge specific capacity of 150.3 mAh g–1 at 0.1 C and coulomb efficiency of 99%.
Two nonsense GLI3 variants are associated with polydactyly and syndactyly in two families by affecting the sonic hedgehog signaling pathway
Authors: Shen Xiaofang , Zhang Shun , Zhang Xin , Zhou Taifeng , Rui Yongjun
Published: February 2022

Background

Polydactyly and syndactyly are congenital limb deformities, segregating in an autosomal‐dominant fashion. The variants in the GLI3 gene are closely related to congenital limb malformations. However, the causes underlying polydactyly and syndactyly are not well understood.

Methods

We conducted a whole‐exome sequencing on two four‐generation Chinese families with polydactyly and syndactyly. Then c.2374C>T and c.1728C>A mutant plasmids were transfected to HEK293T cells and mice limb bud cells to explore the functional consequences of these variants. Western blot and real‐time quantitative PCR were used to analyze the expression of GLI3 and Shh.

Results

In these two families, the known GLI3 variant (NM_000168.6:c.2374C>T) and the novel GLI3 variant (NM_000168.6:c.1728C>A) contributed to polydactyly and syndactyly. Additionally, the GLI3 c.2374C>T mutant plasmid led to truncated GLI3 protein, and the GLI3 c.1728C>A mutant plasmid led to degraded GLI3 protein. Simultaneously, we demonstrated that the GLI3‐mutant plasmids led to decreased Shh expression in mice limb bud cells.

Conclusion

We demonstrated that the novel GLI3 variant (c.1728C>A) and known GLI3 variant (c.2374C>T) contributed to the malformations in two four‐generation pedigrees with polydactyly and syndactyly by affecting SHH signaling.
Magnetic resonance imaging contrast enhancement synthesis using cascade networks with local supervision
Authors: Xie Huiqiao , Lei Yang , Wang Tonghe , Roper Justin , Axente Marian , Bradley Jeffrey D. , Liu Tian , Yang Xiaofeng
Published: March 2022

Purpose

Gadolinium‐based contrast agents (GBCAs) are widely administrated in MR imaging for diagnostic studies and treatment planning. Although GBCAs are generally thought to be safe, various health and environmental concerns have been raised recently about their use in MR imaging. The purpose of this work is to derive synthetic contrast enhance MR images from unenhanced counterpart images, thereby eliminating the need for GBCAs, using a cascade deep learning workflow that incorporates contour information into the network.

Methods and materials

The proposed workflow consists of two sequential networks: (1) a retina U‐Net, which is first trained to derive semantic features from the non‐contrast MR images in representing the tumor regions; and (2) a synthesis module, which is trained after the retina U‐Net to take the concatenation of the semantic feature maps and non‐contrast MR image as input and to generate the synthetic contrast enhanced MR images. After network training, only the non‐contrast enhanced MR images are required for the input in the proposed workflow. The MR images of 369 patients from the multimodal brain tumor segmentation challenge 2020 (BraTS2020) dataset were used in this study to evaluate the proposed workflow for synthesizing contrast enhanced MR images (200 patients for five‐fold cross‐validation and 169 patients for hold‐out test). Quantitative evaluations were conducted by calculating the normalized mean absolute error (NMAE), structural similarity index measurement (SSIM), and Pearson correlation coefficient (PCC). The original contrast enhanced MR images were considered as the ground truth in this analysis.

Results

The proposed cascade deep learning workflow synthesized contrast enhanced MR images that are not visually differentiable from the ground truth with and without supervision of the tumor contours during the network training. Difference images and profiles of the synthetic contrast enhanced MR images revealed that intensity differences could be observed in the tumor region if the contour information was not incorporated in network training. Among the hold‐out test patients, mean values and standard deviations of the NMAE, SSIM, and PCC were 0.063±0.022, 0.991±0.007 and 0.995±0.006, respectively, for the whole brain; and were 0.050±0.025, 0.993±0.008 and 0.999±0.003, respectively, for the tumor contour regions. Quantitative evaluations with five‐fold cross‐validation and hold‐out test showed that the calculated metrics can be significantly enhanced (p‐values ≤ 0.002) with the tumor contour supervision in network training.

Conclusion

The proposed workflow was able to generate synthetic contrast enhanced MR images that closely resemble the ground truth images from non‐contrast enhanced MR images when the network training included tumor contours. These results suggest that it may be possible to minimize the use of GBCAs in cranial MR imaging studies.
Combined application of DP4+ and ANN‐PRA to determine the relative configuration of natural products: The alpha‐bisabol case study
Authors: dos Santos Fernando Martins , da Silva Mota Gunar Vingre , Martorano Lucas Haidar , de Albuquerque Ana Carolina Ferreira , da Silva Claudinei Alves , da Silva Adalberto Manoel , de Jesus Chaves Neto Antônio Maia , Valverde Alessandra Leda , Cardoso Evani Ferreira , Costa Fabio Luiz Paranhos
Published: March 2022

The combination of computational methods and experimental data from Nuclear Magnetic Resonance (NMR) is a considerably valuable tool in the elucidation of new natural product structures and, also, in the structural revision of previously reported compounds. Until recently, only classical statistical parameters were used, for example, linear correlation coefficient (R2), mean absolute error (MAE), or root mean square deviation (RMSD), as a way to statistically “validate” the structure pointed out by experimental NMR spectra. Regarding the resolution of the relative configuration of organic molecules, novel tools were available in the last few years to assist in the NMR elucidation process. The most relevant are DP4+, which is based on a Bayesian probability, and ANN‐PRA, which is based on artificial neural networks. The combined application of these tools has become the most accurate and important alternative to solve structural and stereochemical problems in natural product chemistry. Therefore, herein, in this case study, we intended to promote these novel tools, exploring the strengths and limitations of each approach in resolving the relative configuration of the sesquiterpene alpha‐bisabol. We also highlighted the advantages of the complementary use of H‐ and C‐DP4+ to obtain optimal results in the differentiation of the stereoisomers, validating the proposal with ANN‐PRA method.
Nachruf auf Rudhard Klaus Müller (1936–2021)
Authors: Engewald Werner , Teske Jörg
Published: March 2022

Am 16. November starb Rudhard Klaus Müller. Er war ein Wegbereiter des Fachs Toxikologie und machte sich verdient im Kampf gegen Doping.
Chemiedidaktik: Vom Farbstoff zur Kopie
Authors: Ducci Matthias
Published: March 2022

Ende des 19. Jahrhunderts entwickelten Forscher mit einem Thiazolfarbstoff ein Kopierverfahren, das als Diazotypie später wirtschaftlich erfolgreich wurde. Heute liefert das Verfahren Stoff für den Chemieunterricht. Schüler:innen können den Entdeckungsweg mit Experimenten nachvollziehen, lernen dabei eine photochemische Reaktion kennen und erzeugen selbst Kopien.
Qubits aus dem Elektronenstrahl
Authors: Baum Peter
Published: March 2022

Mittels Laserlicht lassen sich die Elektronen in einem Elektronenstrahl in Qubits verwandeln. Diese Materiewellen aus einem der einfachsten Elementarteilchen eröffnen neue Möglichkeiten in der Quantenphysik. Außerdem entstehen extrem kontrastreiche Attosekunden‐Elektronenimpulse für die filmische Abbildung von atomaren Reaktionen in Raum und Zeit.
Eine supraleitende Diode
Authors: Paradiso Nicola , Strunk Christoph
Published: March 2022

Halbleiterdioden sind elementare Bestandteile der Elektronik. Sie leiten Strom in einer Richtung sehr viel besser als in der entgegengesetzten und stellen somit Ventile für den elektrischen Strom dar. Sie dienen zur Gleichrichtung von Wechselströmen, zur Spannungsstabilisierung und für viele andere Anwendungen. Supraleitende Dioden könnten den Weg zu stromsparenden elektronischen Komponenten ebnen.
Accelerating Cell Migration along Radially Aligned Nanofibers through the Addition of Electrosprayed Nanoparticles in a Radial Density Gradient
Authors: Xue Jiajia , Wu Tong , Qiu Jichuan , Xia Younan
Published: February 2022

Scaffolds capable of promoting cell migration from the periphery toward the center along with the radial direction hold promises for tissue regeneration. Here a simple and general method is reported based on masked electrospray for the fabrication of such scaffolds by depositing collagen nanoparticles on radially aligned nanofibers in a radial density gradient. Placed between the metallic needle and the collector, an aperture with tunable opening sizes serves as the mask. By increasing the size of the opening at a fixed speed, the electrosprayed particles take a radial density gradient that decreases from the center to the periphery. When deposited on a glass slide, the radial density gradient of collagen nanoparticles promotes the migration of fibroblasts from the periphery toward the center. By replacing the glass slide with a scaffold comprised of radially aligned nanofibers, a synergetic effect arises to further accelerate cell migration along the radial direction. The synergistic effect can be attributed to a unique combination of the topographic cue arising from the aligned nanofibers and the haptotactic cue enabled by the graded nanoparticles. This study demonstrates a method to maximize cell migration from the periphery toward the center through a combination of topographic and haptotactic cues.
Linear Correlation Between Confined Explosive Quantity and Dent Volume of an Underlying Aluminium Block Using the SSRT Setup
Authors: Bauer Lukas , Benz Maximilian , Klapötke Thomas M.
Published: February 2022

The SSRT setup gives smart access to test various properties of explosive materials and requires only little substance quantities. Unlike the standardized SSRT, we studied the bulge development from the blast of different amounts of PETN (200–1300 mg). The bulge of the corresponding aluminum blocks was evaluated with the help of a profilometer (Keyence VR‐5200). This device, which measures the volume of the dents using the offset of structured light projected on the object, has allowed us to analyze the differences precisely. Despite the experimental limitations and the resulting undirected explosion direction, a throughout linear correlation between the respective amounts of PETN and the resulting dent depth could be determined. Our study thus forms an illustrative development of how the explosion behavior, represented by the dent of an aluminum block, of compressed energetic materials behaves in with increasing filling quantity, which is transferable to larger experimental setups as well as to other explosives.
Radiotherapy guidelines for rectal cancer in China (2020 Edition)
Authors: Liu Shixin , Jin Jing
Published: March 2022

Rectal cancer is one of the most common malignant tumors. In China, rectal cancer has been the third most frequently diagnosed cancer and the fifth leading cause of cancer death, with changes of residents’ lifestyle factors and diets. The best treatment for rectal cancer depends on many factors. Multidisciplinary Treatment has become the basis for improving the therapeutic effect, in which radiology is increasingly necessary for treating patients with rectal cancer. For patients who have extensive, fixed, bulky tumors or obvious nodal disease, radiotherapy and chemotherapy combined with surgery has emerged as the standard of care. For patients with metastatic disease, the reasonable combination of local and systemic therapy might be an alternative. Improvements in imaging, pathological diagnosis and radiation techniques provide a solid foundation for promoting the level of clinical practice in rectal cancer. High‐quality magnetic resonance imaging distinguishing risk stratification, molecular markers predicting therapeutic effect and prognosis, magnetic resonance imaging in delineating target volumes drawn, intensity‐modulated radiation therapy, and image‐guides radiation therapy for precision treatment delivery are all being widely applied in multiple centers. Furthermore, as the role of targeted therapy and immune therapy has become increasingly prominent, the attempt of combined radiotherapy is also ongoing. In view of the characteristics and current situation of diagnosis and treatment of rectal cancer in China, the guidelines will present the basis and reference for combined treatment and standardized treatments. Meanwhile, there may be continuous new advances in clinical practice, and that will be a new basis to update the guidelines, directly benefiting all rectal cancer patients and facilitating discipline developments.
The effects of geometrical flame feature on radiant heat flux prediction of horizontal jet flames using line source model
Authors: Ab Aziz Nur Shahidah , Md. Kasmani Rafiziana
Published: February 2022

Radiant heat flux and impingement are the most common contributors to accident escalation involving jet fire. Thus, it is important to account for the radiant heat flux by using a semi‐empirical model as it is easy, cheaper, and could provide a reliable prediction. In this study, experimental observations were carried out for both free and impinging jet release. Propane was used as fuel and released from a circular nozzle with a diameter of 7.15 and 9.8 mm. The release velocity was fixed between 27 to 65 m/s, which is considered a subsonic release. In this work, two bases for radiant heat prediction using LSM were used: (i) horizontal kite shape approach and (ii) flame trajectory approach. It was observed that the prediction of radiant heat flux based on the flame trajectory for the free jet fire scenario gave the R2 value of 0.99, suggesting that the flame trajectory could give a better prediction as compared to the horizontal kite shape approach with R2 = 0.94. By using a similar assumption for impinging jet flames, it was observed that LSM based on flame trajectory could be used to predict the radiant heat flux with R2 = 0.99 for each case scenario.
Characterization of Lattice Defects in Refractory Metal High‐Entropy Alloy HfNbTaTiZr by Means of Positron Annihilation Spectroscopy
Authors: Čížek Jakub , Vlasák Tomáš , Melikhova Oksana
Published: March 2022

Lattice defects in refractory metal high‐entropy alloy HfNbTaTiZr are investigated using positron lifetime spectroscopy combined with coincidence Doppler broadening (CDB) spectroscopy. Annealing of HfNbTaTiZr alloy at 1000 °C results in full recovery of defects and formation of single‐phase random solid solution characterized by the bulk positron lifetime of 141 ps. This value is in accordance with the theoretical estimation. Quenching of the alloy from high temperature prevents recovery of thermally equilibrium vacancies and enables to retain a high concentration of vacancies in the sample at ambient temperature. For single vacancies in the HfNbTaTiZr alloy, a characteristic positron lifetime of 212 ps is measured, which is significantly shorter than the value estimated by theoretical calculations. It indicates that there is considerable ion relaxation around vacancies. The CDB spectroscopy investigations reveal that vacancies in HfNbTaTiZr alloy are not distributed randomly but are preferentially coupled with Hf solutes.
Influence of Fe2O3 Content on Acoustic Properties of Backing Materials and Development and Utilization of Acoustic Emission Sensors
Authors: Guo Rui , Zhang Xiaofang , Liu Fen , Huang Shifeng , Yang Changhong , Li Haoran , Lin Xiujuan
Published: February 2022

Fe2O3 and epoxy resin sensor substrate materials (Fe2O3/epoxy resin composite material) are prepared in this article. A series of acoustic emission sensors are prepared by using composite material as sensor substrate, and the effect of Fe2O3 content in composite material on sensor performance is studied. The effect of Fe2O3 content in the composite material on the performance of the sensor is studied through the simulated lead‐breaking experiment, and the self‐made sensor is calibrated by using the calibration system. Nondestructive testing of concrete materials with different strengths is carried out by selecting the sensor with the best performance. The results show that the content of Fe2O3 in the composite increases to 50%, the epoxy resin matrix reaches saturation point of accommodate Fe2O3 powder, and the propagation velocity of ultrasonic waves reaches the lowest point when it passes through the composite. The sensor with 50% Fe2O3 content as a backing layer has the highest sensitivity and signal‐to‐noise ratio. The relationship between the strength of concrete material and acoustic attenuation and frequency is established by using this sensor, and the law can be used to evaluate the strength and mechanical properties of concrete material without destroying them.
Icarisid II rescues cognitive dysfunction via activation of Wnt/β‐catenin signaling pathway promoting hippocampal neurogenesis in APP/PS1 transgenic mice
Authors: Xiao Hong‐He , Chen Ji‐Cong , Li He , Li Rui‐Hai , Wang Hai‐Bo , Song Hui‐Peng , Li Hong‐Yan , Shan Guo‐Shun , Tian Yu , Zhao Yu‐Meng , Tian Jin‐Ming , Yang Jing‐Xian
Published: March 2022

Restoring the compromised neurogenesis has been served as a potential strategy to rescue cognitive dysfunction of Alzheimer's disease (AD). In this study, we explored whether icarisid II (ICS II), a natural product possessing powerful neuroprotection, could recover the neurogenesis dysfunction of APP/PS1 mice, and investigated its underlying mechanisms. Our results showed that oral administration of ICS II could alleviate cognitive injuries of APP/PS1 mice, promote hippocampal neurogenesis, as well as stimulate Wnt/β‐catenin signal pathway confirmed by upregulated Wnt‐3a, phosphorylated glycogen synthase kinase‐3β (p‐GSK‐3β), and β‐catenin. ICS II also depressed mitochondrial fission evidenced by upregulated Mitofusin 1 (Mfn 1) and Mitofusin 2 (Mfn 2), and downregulated mitochondrial fission 1 protein (Fis 1), mitochondrial fission factor (Mff), and phosphorylated dynamin‐related protein 1 (p‐Drp 1). However, these effects of ICS II were blunted by XAV‐939, an inhibitor of Wnt/β‐catenin signaling pathway. In summary, our findings revealed that ICS II could improve neurogenesis and inhibit mitochondrial fission via activation of the Wnt/β‐catenin signaling pathway, which contributed to cognitive function restoration of APP/PS1 mice. This study discovered a novel mechanism involving neurogenesis regulation underlying the therapeutic effects of ICS II against AD.
Structure‐dependence in initial decomposition of trans‐1,2‐dimethylcyclohexyl isomers: Kinetic exploration and conformational analysis
Authors: Bian Huiting , Wang Yongjin , Li Jing , Zhao Jun
Published: March 2022

To elucidate the combustion behaviors of trans‐1,2‐dimethylcyclohexyl isomers, their initial decomposition have been explored by employing quantum chemical calculations coupled with transition state theory. All conformational structures and their interconversion mechanisms were studied. Originated from distinct conformers, all accessible transition states were explicitly identified in multiple paths for H‐transfer or β‐scission, and then were carefully used in kinetic predictions. The fairly speedy conformation fairly dominates over decomposition that allows thoroughly evaluating the contribution of various conformers to the final kinetics. Conformational analysis unravels that the most favorable 1,5 H‐transfer is only feasible for one twist‐boat with radical site in axial side chain accompanied by one isoclinal methyl group. The results for β‐scissions are affected by steric energies and substituent effects remained in conformational structures. These findings facilitate to finally figure out the proper kinetic parameters for each decomposition reaction for the implication in kinetic modeling simulation.
Modification and validation of the simultaneous detection of 38 pesticide residues method by ultra‐high‐performance liquid chromatography/tandem mass spectrometry with QuEChERS extraction in different oil crops and products
Authors: Lv Xi , Wang Fengzhong , Cui Ying , Fan Bei , Kong Zhiqiang , Yan Tingcai , Li Minmin
Published: March 2022

Rationale

Oil crops and products are important food materials in daily life. Pesticide residues in food could directly and indirectly endanger human health. However, the method for detecting multiple pesticides simultaneously is limited. In this study, an easy and efficient method for the simultaneous determination of 38 pesticides in oil crops and products was established and validated.

Methods

All samples were treated with a modified QuEChERS procedure followed by ultra‐high‐performance liquid chromatography/tandem mass spectrometry (UHPLC/MS/MS) analysis. Mass spectrometry was performed in positive and negative ion electrospray ionization mode. The mobile phase consisted of 0.1% formic acid in water and 0.1% formic acid in acetonitrile. The column used was a Poroshell 120 EC‐C18 and the flow rate was 0.3 mL/min.

Results

The method was validated so that the calibration curves for all pesticides had good linearity in the concentration range of 10–1000 μg/L with correlation coefficients (R2) above 0.9945. The recovery rates were between 70.1 and 120.0%, with relative standard deviations (RSDs) (n = 6) ≤20.0%. The limits of quantification (LOQs) ranged from 0.5 to 10 μg/kg, limits of detection (LODs) ranged from 2.0 to 30 μg/kg, and the matrix effect (ME) ranged from −18.77 to 19.33%, respectively.

Conclusions

The method proved to be accurate, sensitive, and stable. It can be used for rapid screening and confirmation of 38 pesticide residues in oil crops and products which takes 10 min for sample extraction and clean‐up with less requirement of solvents. This study provides a technical basis for regulatory analysis and quality supervision of foods.
Comparative effectiveness of N95, surgical or medical, and non‐medical facemasks in protection against respiratory virus infection: A systematic review and network meta‐analysis
Authors: Kim Min Seo , Seong Dawon , Li Han , Chung Seo Kyoung , Park Youngjoo , Lee Minho , Lee Seung Won , Yon Dong Keon , Kim Jae Han , Lee Keum Hwa , Solmi Marco , Dragioti Elena , Koyanagi Ai , Jacob Louis , Kronbichler Andreas , Tizaoui Kalthoum , Cargnin Sarah , Terrazzino Salvatore , Hong Sung Hwi , Abou Ghayda Ramy , Radua Joaquim , Oh Hans , Kostev Karel , Ogino Shuji , Lee I‐Min , Giovannucci Edward , Barnett Yvonne , Butler Laurie , McDermott Daragh , Ilie Petre‐Cristian , Shin Jae Il , Smith Lee
Published: February 2022

The aim of this systematic review and network meta‐analysis is to evaluate the comparative effectiveness of N95, surgical/medical and non‐medical facemasks as personal protective equipment against respiratory virus infection. The study incorporated 35 published and unpublished randomized controlled trials and observational studies investigating specific mask effectiveness against influenza virus, SARS‐CoV, MERS‐CoV and SARS‐CoV‐2. We searched PubMed, Google Scholar and medRxiv databases for studies published up to 5 February 2021 (PROSPERO registration: CRD42020214729). The primary outcome of interest was the rate of respiratory viral infection. The quality of evidence was estimated using the GRADE approach. High compliance to mask‐wearing conferred a significantly better protection (odds ratio [OR], 0.43; 95% confidence interval [CI], 0.23–0.82) than low compliance. N95 or equivalent masks were the most effective in providing protection against coronavirus infections (OR, 0.30; CI, 0.20–0.44) consistently across subgroup analyses of causative viruses and clinical settings. Evidence supporting the use of medical or surgical masks against influenza or coronavirus infections (SARS, MERS and COVID‐19) was weak. Our study confirmed that the use of facemasks provides protection against respiratory viral infections in general; however, the effectiveness may vary according to the type of facemask used. Our findings encourage the use of N95 respirators or their equivalents (e.g., P2) for best personal protection in healthcare settings until more evidence on surgical and medical masks is accrued. This study highlights a substantial lack of evidence on the comparative effectiveness of mask types in community settings.
How soil carbon fractions relate to soil properties and crop yields in dryland cropping systems?
Authors: Sainju Upendra M. , Liptzin Daniel , Stevens William B.
Published: March 2022

Soil labile C fractions have been proposed as promising soil health indicators, but they have not been related to extensive soil properties and crop yields. We evaluated the relationships among soil organic carbon (SOC), labile C fractions, 62 soil physical, chemical, biological, and biochemical properties, and mean crop yields in two long‐term (14‐ and 36‐yr‐old) sites (Froid and Sidney, eastern Montana) under dryland farming. Soil C fractions were SOC, soil inorganic carbon (SIC), water‐extractable carbon (WEC), KMnO4–extractable carbon (POXC), potential carbon mineralization (PCM), and microbially active carbon (MAC). Treatments were conventional till and no‐till spring wheat (Triticum aestivum L.)/barley (Hordeum vulgaris L.), pea (Pisum sativum L.), and fallow rotations without N fertilization in Froid and with and without N fertilization in Sidney. Carbon fractions were greater in no‐till continuous cropping than till crop–fallow, with no effect of N fertilization at both sites. The principal component analysis showed that PCM was strongly associated with most soil physical, chemical, biological, and biochemical properties, followed by SOC, POXC, WEC, MAC, and SIC at both sites. More C fractions were related to soil properties in longer than shorter duration of the experiment. All C fractions, except SIC, were also related to mean crop yields across years. Although SOC was related to soil properties and crop yields, PCM may be used as a promising soil health indicator because of its greater sensitivity to management practices and better relationship to soil properties and crop yields than other labile C fractions.
Partially Reduced Graphene Oxide Membranes Crosslinked by an Anionic Porphyrin: Green Fabrication for High‐Performance Ion Sieving
Authors: Xu Xiao‐Ling , Mei Hongxin , Peng Aiping , Guo Yanjin , Ouyang Banlai , Liu Xiujuan , Li Ling , Chen Weihong
Published: March 2022

GO membranes crosslinked by planar cation (e. g. TMPyP, a cationic porphyrin) meet the requirements of green fabrication, because TMPyP can pre‐assemble on GO sheets. However, their ion sieving performance are unsatisfactory. With shortened water channels, reduced graphene oxide (rGO) membranes owe high water flux, yet the retention of multivalent anions may goes down distinctly on account of Donnan effect decreasing obviously. Herein, we focus on the assembly between partially reduced graphene oxide (p‐rGO) and Anionic planar molecule (tetrasulfonic tetraphenyl porphyrin, TPPS), and then fabricate p‐rGO/TPPS composite membranes via assembling p‐rGO/TPPS sheets on base membrane. Anionic planar molecule is firstly used as crosslinking agent for graphene‐based membranes, which has the advantage of 100% atomic efficiency. The fabricated p‐rGO/TPPS membranes show better sieving performance than GO/TMPyP membranes on both side of rejection of Na2SO4 and water flux. Moreover, water flux go up to around another double though rejection decline slightly as the polyther sulfone (PES) base membrane with large surface pores is used.
Stability and Performance Enhancement of an Oligo (phenylene vinylene) Photocatalyst via Surface Grafting onto TiO2 for Visible‐Light Indigo Carmine Degradation
Authors: Acelas Mauricio , Castellanos Nelson J. , Sierra César A.
Published: March 2022

The chemical immobilization of a dibenzoic acid oligo (phenylene vinylene) (OPV) derivative for TiO2 sensitization was evaluated as a strategy to enhance both the stability and photocatalytic performance of this π‐conjugated moiety when applied to the photodegradation of indigo carmine dye (IC) as model pollutant. The results show that the electron injection from the photoexcited OPV to the TiO2 conduction band remarkably boosts the IC degradation ability under visible light illumination. The use of SiO2 as non‐photoactive support was also investigated to simultaneously determine the role of the inorganic support in the photocatalytic process. The spectroscopic, thermal, and surface characterization validated the successful grafting of the OPV to the inorganic supports. Moreover, superoxide radical and singlet oxygen were established as the active species involved in the dye degradation identifying an additional direct reducing pathway. Interestingly, the use of electron donors proved to be an ineffective approach to increase the system performance, entailing that the OPV regeneration proceeds chiefly via back electron transfer processes. Finally, the reusability tests confirmed that TiO2/OPV material retains up to 86 % of their photocatalytic activity during the first five cycles, demonstrating a critical enhancement in the organic conjugated framework stability.
Polysulfide Regulation by Hypervalent Iodine Compounds for Durable and Sustainable Lithium–Sulfur Battery
Authors: Wang Zhouhao , Hu Junping , Liu Jing , Lim Yew Von , Song Haobin , Wang Ye , He Tingting , Huang Chunlai , Yan Xinwen , Zhang Daohong , Huang Shaozhuan
Published: February 2022

Herein, a type of hypervalent iodine compound—iodosobenzene (PhIO)—is proposed to regulate the LiPSs electrochemistry and enhance the performance of Li‐S battery. PhIO owns the practical advantages of low‐cost, commercial availability, environmental friendliness and chemical stability. The lone pair electrons of oxygen atoms in PhIO play a critical role in forming a strong Lewis acid–base interaction with terminal Li in LiPSs. Moreover, the commercial PhIO can be easily converted to nanoparticles (≈20 nm) and uniformly loaded on a carbon nanotube (CNT) scaffold, ensuring sufficient chemisorption for LiPSs. The integrated functional PhIO@CNT interlayer affords a LiPSs‐concentrated shield that not only strongly obstructs the LiPSs penetration but also significantly enhances the electrolyte wettability and Li+ conduction. The PhIO@CNT interlayer also serves as a “vice current collector” to accommodate various LiPSs and render smooth LiPSs transformation, which suppresses insulating Li2S2/Li2S layer formation and facilitates Li+ diffusion. The Li−S battery based on PhIO@CNT interlayer (6 wt% PhIO) exhibits stable cycling over 1000 cycles (0.033% capacity decay per cycle) and excellent rate performance (686.6 mAh g−1 at 3 C). This work demonstrates the great potential of PhIO in regulating LiPSs and provides a new avenue towards the low‐cost and sustainable application of Li−S batteries.
Correlating Symmetries of Low‐Frequency Vibrations and Self‐Trapped Excitons in Layered Perovskites for Light Emission with Different Colors
Authors: Lin Miao‐Ling , Dhanabalan Balaji , Biffi Giulia , Leng Yu‐Chen , Kutkan Seda , Arciniegas Milena P. , Tan Ping‐Heng , Krahne Roman
Published: February 2022

The soft hybrid organic–inorganic structure of two‐dimensional layered perovskites (2DLPs) enables broadband emission at room temperature from a single material, which makes 2DLPs promising sources for solid‐state white lighting, yet with low efficiency. The underlying photophysics involves self‐trapping of excitons favored by distortions of the inorganic lattice and coupling to phonons, where the mechanism is still under debate. 2DLPs with different organic moieties and emission ranging from self‐trapped exciton (STE)‐dominated white light to blue band‐edge photoluminescence are investigated. Detailed insights into the directional symmetries of phonon modes are gained using angle‐resolved polarized Raman spectroscopy and are correlated to the temperature‐dependence of the STE emission. It is demonstrated that weak STE bands at low‐temperature are linked to in‐plane phonons, and efficient room‐temperature STE emission to more complex coupling to several phonon modes with out‐of‐plane components. Thereby, a unique view is provided into the lattice deformations and recombination dynamics that are key to designing more efficient materials.
Layered Cathode Materials: Precursors, Synthesis, Microstructure, Electrochemical Properties, and Battery Performance
Authors: Huang Bin , Cheng Lei , Li Xinze , Zhao Zaowen , Yang Jianwen , Li Yanwei , Pang Youyong , Cao Guozhong
Published: February 2022

The exploitation of clean energy promotes the exploration of next‐generation lithium‐ion batteries (LIBs) with high energy‐density, long life, high safety, and low cost. Ni‐rich layered cathode materials are one of the most promising candidates for next‐generation LIBs. Numerous studies focusing on the synthesis and modifications of the layered cathode materials are published every year. Many physical features of precursors, such as density, morphology, size distribution, and microstructure of primary particles pass to the resulting cathode materials, thus significantly affecting their electrochemical properties and battery performance. This review focuses on the recent advances in the controlled synthesis of hydroxide precursors and the growth of particles. The essential parameters in controlled coprecipitation are discussed in detail. Some innovative technologies for precursor modifications and for the synthesis of novel precursors are highlighted. In addition, future perspectives of the development of hydroxide precursors are presented.