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Here, we present the synthesis of a novel quaternary compound, iodide carbonate Na5(CO3)2I, at 18(1) and 25.1(5) GPa in laser-heated diamond anvil cells. Single-crystal synchrotron X-ray diffraction provides accurate structural data for Na5(CO3)2I and shows that the structure of the material can be described as built of INa8 square prisms, distorted NaO6 octahedra, and trigonal planar CO32− units. Decompression experiments show that the novel iodide carbonate is recoverable in the N2 atmosphere to ambient conditions. Our ab initio calculations agree well with the experimental structural data, provide the equation of state, and shed light on the chemical bonding and electronic properties of the new compound. [ABSTRACT FROM AUTHOR]

Simple Summary: In this paper, two new genera with two new species of Dermaptera are described from the Middle Jurassic Jiulongshan Formation of Daohugou, Inner Mongolia, China. The discovery of these two new species enriches the comparatively meagre fossil record of Dermaptera, particularly from the Middle Jurassic. The description of Applanatiforceps angustus is another brick laid in the foundation of protodiplatyid diversity, and the new genus Ekpagloderma gracilentum highlights the diversity of cercal forms among Aglyptodermatinae and the remarkable homogeneity of the general morphology of groups within this clade. Two new genera and species of Dermaptera are described from the Middle Jurassic Jiulongshan Formation of Daohugou, Inner Mongolia, China: Applanatiforceps angustus gen. et sp. nov. in the archidermapteran family Protodiplatyidae, and Ekpagloderma gracilentum gen et sp. nov. in the eodermapteran family Semenoviolidae. Applanatiforceps shares the typical characters of the extinct suborder Archidermaptera (e.g., pentamerous meta tarsi, filiform and multimerous cerci) and externalized ovipositor. The family identity of the Protodiplatyidae can be further distinguished by comparing this new genus with other genera of the Protodiplatyidae. As a result of its large compound eyes, tegmina without venation, body sparsely setose, legs rather short and slender, and shape of the veinless tegmina, Ekpagloderma is classified in the subfamily Aglyptodermatinae. Ekpagloderma not only has the typical features of the Aglyptodermatinae, but also exhibits a more primitive slender segmented cerci, which is different from all other genera of Eodermaptera. In fact, the diversity of Eodermaptera as known today indicates some of the challenges in understanding the suborder and whether or not it is monophyletic as historically construed, or if the separation of Turanodermaptera is justified. [ABSTRACT FROM AUTHOR]

The electroreductive cross-electrophile coupling which has emerged as a powerful, green and efficient method for constructing challenging C–C bonds has attracted increasing attention from organic chemists. Most of the previous works focus on direct two-electrophile cross-coupling. In this work, the nickel-catalyzed three-electrophile electroreductive cross-electrophile coupling which offers direct convergent synthesis to target molecules from easily-available and cheap substrates has been developed. A wide range of alkyl aryl ketones are accessed from alkyl halides, aryl iodides and propyl chloroformate under mild conditions, avoiding the use of over-stoichiometric reductants, excess quantities of additives and activators, and superstoichiometric CO gas or metal carbonyl complexes which are toxic, environmentally unfriendly and can be inconvenient to handle. The scale-up experiment indicates the good scalability of electrosynthesis compared to traditional synthesis. High chemo-selectivity can be achieved through an increase in the current. Mechanistic investigation suggests that the electron transfer rate from the cathode to Ni catalysts plays a vital role in this protocol. Our approach demonstrates a novel electrochemical selectivity-controlled strategy in cross-electrophile coupling. [ABSTRACT FROM AUTHOR]

Chemical stability of the alkali halides NaCl and KCl has allowed for their use as inert media in high-pressure high-temperature experiments. Here we demonstrate the unexpected reactivity of the halides with metals (Y, Dy, and Re) and iron oxide (FeO) in a laser-heated diamond anvil cell, thus providing a synthetic route for halogen-containing binary and ternary compounds. So far unknown chlorides, Y2Cl and DyCl, and chloride carbides, Y2ClC and Dy2ClC, were synthesized at ~40 GPa and 2000 K and their structures were solved and refined using in situ single-crystal synchrotron X-ray diffraction. Also, FeCl2 with the HP-PdF2-type structure, previously reported at 108 GPa, was synthesized at ~160 GPa and 2100 K. The results of our ab initio calculations fully support experimental findings and reveal the electronic structure and chemical bonding in these compounds. The chemical stability of alkali halides has caused them to be exploited as inert media in high-pressure, high-temperature experiments. Here, NaCl and KCl are unexpectedly found to react with yttrium, dysprosium and iron oxide in a laser-heated diamond anvil cell, producing Y2Cl, DyCl, Y2ClC and Dy2ClC at ~40 GPa and 2000 K and FeCl2 at ~160 GPa and 2100 K. [ABSTRACT FROM AUTHOR]

Bubble defects severely affect the optical properties of single-crystal fibers (SCFs), so it is necessary to avoid the incorporation of bubbles during crystal growth. The process of bubbles entering a crystal was observed during pulling of Lu3Al5O12 (LuAG) SCFs from ceramic pedestals by the laser-heated pedestal growth (LHPG) method. The effects of orientation and growth chamber pressure on the density and size of bubbles as well as on stress distribution were fully studied. <111>-oriented LuAG crystal fibers are likely to incorporate more and larger bubbles than <100>-oriented fibers. The low pressure in the growth chamber can limit the formation and transport of bubbles, and the bubble densities are decreased by nearly 50% with a chamber pressure of 0.3 atm. Notably, the <111>-oriented LuAG crystal fibers are more sensitive to pressure with an almost 40% decrease in the average bubble size and stress. [ABSTRACT FROM AUTHOR]

Electroreductive cross-electrophile coupling has emerged as a powerful and efficient method for constructing challenging C–C or C–X bonds, providing several advantages including highly efficient electron transfer, tunable reducing potential, direct electricity-activation of substrates and good scalability. In electroreductive cross-electrophile coupling, a high loading of a transition metal catalyst is required to facilitate the transfer of electrons from the cathode to organic halides, making it unsuitable for sensitive organic halides such as chloroformates. As a result, the electroreductive XEC of readily accessible chloroformates with alkyl halides for ester synthesis remains a largely unmet challenge. In this work, catalyst-free electrochemically driven cross-electrophile esterification of alkyl halides has been developed. A wide range of 2-phenylacetic esters which represent an important class of molecules in synthetic and medicinal chemistry are accessed from simple and cheap alkyl halides and alkyl chloroformates under mild reaction conditions. Various functional groups were well tolerated, affording up to 98% yields. This protocol would contribute a lot for the further development of electrochemically driven cross-electrophile coupling. [ABSTRACT FROM AUTHOR]

Lu2O3 crystals have attracted intense attention due to their great potential in the field of high power solid-state lasers. Lu2O3 single crystal fibers (SCFs) with a length-to-diameter ratio of >200 : 1 were successfully grown by the laser heated pedestal growth (LHPG) method for the first time. The relationships between the crystal diameter and thermal stress were investigated in detail. Crystal cracking was effectively solved by reducing the diameter of the crystal fiber. Besides, the influence of the growth atmosphere on the crystal growth was also demonstrated. The crystals grown in a mixture of 95% O2 and 5% Ar were colorless and transparent. The XRD pattern showed that the phase of Lu2O3 was pure, and the crystal quality along the axial and radial directions was measured by Laue back-reflection measurements. Meanwhile, the diameter fluctuations of the obtained Lu2O3 crystal fibers were further reduced by using optimized source rods. [ABSTRACT FROM AUTHOR]

Cryptochromes (CRYs), as blue-light photoreceptors, play a crucial role in regulating flowering time and hypocotyl and cotyledon development. Their physiological functions have been extensively studied in various plant species. However, research on onions remains limited. In this study, we identified AcCRY1 and conducted preliminary investigations into its function. Our results demonstrate that AcCRY1 possesses a conserved domain typical of cryptochromes with high homology to those found in monocots. Furthermore, we examined the expression level of AcCRY1 in onion. The green tissues is significantly higher compared to non-green tissues, and it exhibits a significant response to blue-light induction. AcCRY1 demonstrates cytoplasmic localization under blue-light conditions, while it localizes in the nucleus during darkness, indicating a strong dependence on blue-light for its subcellular distribution. In comparison to cry1 , overexpression of AcCRY1 leads to a significant shorten in seedling hypocotyl length, notable expansion of cotyledons, and acceleration of flowering time. The yeast two-hybrid experiment demonstrated the in vitro interaction between AcCRY1, AcCOP1, and AcSPA1. Additionally, BIFC analysis confirmed their interaction in Onion epidermis. Notably, under blue-light conditions, a significantly enhanced binding activity was observed compared to dark conditions. These findings establish a functional foundation for the regulatory role of AcCRY1 in important physiological processes of onion and provide initial insights into the underlying molecular mechanisms. • The transcript level of AcCRY1 is significantly increased at the initial period of onion from dark to blue light. • The localization of AcCRY1 in onion epidermal cells is regulated by blue light. • AcCRY1 can regulate Arabidopsis photomorphogenesis and flowering under blue light. • AcCRY1 can interact with AcCOP1, AcSPA1 under blue light. [ABSTRACT FROM AUTHOR]

• Economic agglomeration harms sustainable intensification of cultivated land use. • Pathways that economic agglomeration affects sustainable intensification are complex. • Sustainable intensification verifies "pollution halo" and "pollution haven" theories. • Integrated regional development systems can promote multi-objective synergies. The sustainable intensification (SI) of cultivated land use (CLU) is important for achieving global sustainable development goals (SDGs). However, in the rapid advancement of agglomeration economies, it remains unclear whether economic agglomeration (EA) affects SI. Combined with emergy theory, this study utilized socioeconomic and natural environment data from 31 provincial administrative regions from 1990 to 2017 to evaluate the SI level in China. It further analyzed the impact of EA on SI using a spatial econometric model that includes mediating effects. The results showed that the EA level in China continued to rise, whereas the SI level continued to decline from 1990 to 2017. The mediating effect analysis showed that fiscal support for agriculture and agricultural labor productivity have a suppression effect of |−4.186|% and |−2.002|% in the local region, while cultivated land-use intensity has partial mediation of 6.350% in the local region; and agricultural labor productivity has a suppression effect of |−4.680|% on the surrounding region, while cultivated land-use intensity has stronger partial mediation relative to the local region, even up to 10.402% on surrounding regions. This implies that the impact of EA on SI involves complex paths and spatial differences. This study provides a better understanding of the reasons for the continuous decline in the SI in agglomeration-type economic development and feasible policy proposals. [ABSTRACT FROM AUTHOR]

This letter proposes a fully domain‐independent WiFi‐based gesture recognition system based on the multi‐label adversarial network. Unlike pioneer machine learning works, our system does not require retraining in the target domain, which benefits from our key idea of eliminating fully domain information such as orientations, locations, environment information. The system proposed by us includes three parts: Feature extractor, domain discriminator, and gesture recogniser. The feature extractor attempts to deceive the domain discriminator based on the adversarial network structure so that it is difficult to judge the input domain label, thereby obtaining domain‐independent features and realising fully domain‐independent gesture recognition. Extensive experiments are conducted on the Widar 3.0 dataset and our dataset to evaluate system performance. The results show that our system can achieve an in‐domain recognition accuracy of 93.2% and a cross‐domain recognition accuracy of 87.1%, which is superior to other state‐of‐the‐art works. [ABSTRACT FROM AUTHOR]

[Display omitted] • The three-stage super-efficiency SBM-U model was used to evaluate CLUE of YREB in China. • Heterogeneous agricultural production environment play a vital role in CLUE evaluation. • The OLS and GWR models were used to analyze the driving mechanism of CLUE. • The driving mechanism of CLUE is spatiotemporal non-stationary. • Input-output structure and production factor substitution are main determinants. Improving the cultivated land use ecological efficiency (CLUE) to obtain greater agricultural output at a lower environmental cost, is an important part of effective management of land resources and sustainable intensification (SI). However, when evaluating CLUE, the existing research ignores the heterogeneity of the production environment of different agricultural production units, which leads to a "distortion effect". To address this, this study focuses on the Yangtze River Economic Belt (YREB) in China as the study area and uses a three-stage super-efficiency slacks-based measure-undesirable (three-stage super-efficiency SBM-U) model to evaluate CLUE after excluding the interference of a heterogeneous agricultural production environment. In addition, we constructed ordinary least squares (OLS) and geographically weighted regression (GWR) models to analyze the driving mechanism of CLUE. The results indicate that environmental factors have a significant impact on the evaluation results of CLUE. Ignoring environmental factors leads to an overestimation of CLUE in areas with better environmental conditions, and vice versa. Second, due to the difference in input–output structure and the varied difficulty in production factor substitution, the driving mechanism of CLUE is spatiotemporal non-stationarity. During the study period, gross domestic product per capita, and farmland management scale had a positive effect on CLUE, while industrialization level had a negative effect. The impact of fiscal support for agriculture changed from insignificant to significant, in terms of improving CLUE in the western YREB. The influence direction of the multiple cropping index and agricultural planting structure changes from positive to negative and is concentrated in the east of the YREB. As a result, a series of measures are proposed to promote the improvement of CLUE and realize SI. [ABSTRACT FROM AUTHOR]

Accurate localization in underground coal mining is a challenging technology in coal mine safety production. This paper proposes a low-cost battery-free localization scheme based on depth images, called MineBL. The main idea is to utilize the battery-free low-cost reflective balls as position nodes and realize underground target localization with a series of algorithms. In particular, the paper designs a data enhancement strategy based on small-target reorganization to increase the identification accuracy of tiny position nodes. Moreover, a novel ranging algorithm based on multi-filter cooperative denoising has been proposed, and an optimized weighted centroid location algorithm based on multilateral location errors has been designed to minimize underground localization errors. Many experiments in the indoor laboratories and the underground coal mine laboratories have been conducted, and the experimental results have verified that MineBL has good localization performances, with localization errors less than 30 cm in 95% of cases. Therefore, MineBL has great potential to provide a low-cost and effective solution for precise target localization in complex underground environments. [ABSTRACT FROM AUTHOR]

Transition metal nitrides, particularly those of 5d metals, are known for their outstanding properties, often relevant for industrial applications. Among these metal elements, tungsten is especially attractive given its low cost. In this high‐pressure investigation of the W–N system, two novel ultra‐incompressible tungsten nitride superconductors, namely W2N3 and W3N5, are successfully synthesized at 35 and 56 GPa, respectively, through a direct reaction between N2 and W in laser‐heated diamond anvil cells. Their crystal structure is determined using synchrotron single‐crystal X‐ray diffraction. While the W2N3 solid's sole constituting nitrogen species are N3‐ units, W3N5 features both discrete N3‐ as well as N24‐ pernitride anions. The bulk modulus of W2N3 and W3N5 is experimentally determined to be 380(3) and 406(7) GPa, and their ultra‐incompressible behavior is rationalized by their constituting WN7 polyhedra and their linkages. Importantly, both W2N3 and W3N5 are recoverable to ambient conditions and stable in air. Density functional theory calculations reveal W2N3 and W3N5 to have a Vickers hardness of 30 and 34 GPa, and superconducting transition temperatures at ambient pressure (50 GPa) of 11.6 K (9.8 K) and 9.4 K (7.2 K), respectively. Additionally, transport measurements performed at 50 GPa on W2N3 corroborate with the calculations. [ABSTRACT FROM AUTHOR]

Indoor localization provides robust solutions in many applications, and Wi-Fi-based methods are considered some of the most promising means for optimizing indoor fingerprinting localization accuracy. However, Wi-Fi signals are vulnerable to environmental variations, resulting in data across different times being subjected to different distributions. To solve this problem, this paper proposes an across-time indoor localization solution based on channel state information (CSI) fingerprinting via multi-domain representations and transfer component analysis (TCA). We represent the format of CSI readings in multiple domains, extending the characterization of fine-grained information. TCA, a domain adaptation method in transfer learning, is applied to shorten the distribution distances among several CSI readings, which overcomes various CSI distribution problems at different time periods. Finally, we present a modified Bayesian model averaging approach to integrate the multi-domain outcomes and give the estimated positions. We conducted test-bed experiments in three scenarios on both personal computer (PC) and smartphone platforms in which the source and target fingerprinting data were collected across different days. The experimental results showed that our method outperforms state-of-the-art methods in localization accuracy. [ABSTRACT FROM AUTHOR]

Convenient indoor positioning has become an urgent need due to the improvement it offers to quality of life, which inspires researchers to focus on device-free indoor location. In areas covered with Wi-Fi, people in different locations will to varying degrees have an impact on the transmission of channel state information (CSI) of Wi-Fi signals. Because space is divided into several small regions, the idea of classification is used to locate. Therefore, a novel localization algorithm is put forward in this paper based on Deep Neural Networks (DNN) and a multi-model integration strategy. The approach consists of three stages. First, the local outlier factor (LOF), the anomaly detection algorithm, is used to correct the abnormal data. Second, in the training phase, 3 DNN models are trained to classify the region fingerprints by taking advantage of the processed CSI data from 3 antennas. Third, in the testing phase, a model fusion method named group method of data handling (GMDH) is adopted to integrate 3 predicted results of multiple models and give the final position result. The test-bed experiment was conducted in an empty corridor, and final positioning accuracy reached at least 97%. [ABSTRACT FROM AUTHOR]

A series of isostructural Ln3O2(CN3) (Ln=La, Eu, Gd, Tb, Ho, Yb) oxoguanidinates was synthesized under high‐pressure (25–54 GPa) high‐temperature (2000–3000 K) conditions in laser‐heated diamond anvil cells. The crystal structure of this novel class of compounds was determined via synchrotron single‐crystal X‐ray diffraction (SCXRD) as well as corroborated by X‐ray absorption near edge structure (XANES) measurements and density functional theory (DFT) calculations. The Ln3O2(CN3) solids are composed of the hitherto unknown CN35− guanidinate anion—deprotonated guanidine. Changes in unit cell volumes and compressibility of Ln3O2(CN3) (Ln=La, Eu, Gd, Tb, Ho, Yb) compounds are found to be dictated by the lanthanide contraction phenomenon. Decompression experiments show that Ln3O2(CN3) compounds are recoverable to ambient conditions. The stabilization of the CN35− guanidinate anion at ambient conditions provides new opportunities in inorganic and organic synthetic chemistry. [ABSTRACT FROM AUTHOR]

A series of isostructural Ln3O2(CN3) (Ln=La, Eu, Gd, Tb, Ho, Yb) oxoguanidinates was synthesized under high‐pressure (25–54 GPa) high‐temperature (2000–3000 K) conditions in laser‐heated diamond anvil cells. The crystal structure of this novel class of compounds was determined via synchrotron single‐crystal X‐ray diffraction (SCXRD) as well as corroborated by X‐ray absorption near edge structure (XANES) measurements and density functional theory (DFT) calculations. The Ln3O2(CN3) solids are composed of the hitherto unknown CN35− guanidinate anion—deprotonated guanidine. Changes in unit cell volumes and compressibility of Ln3O2(CN3) (Ln=La, Eu, Gd, Tb, Ho, Yb) compounds are found to be dictated by the lanthanide contraction phenomenon. Decompression experiments show that Ln3O2(CN3) compounds are recoverable to ambient conditions. The stabilization of the CN35− guanidinate anion at ambient conditions provides new opportunities in inorganic and organic synthetic chemistry. [ABSTRACT FROM AUTHOR]

Node localization plays a key and basic role for wireless sensor network. Existing range-free localization approaches suffer from precision limit of positioning, while range-based solutions may obtain good accuracy but pay high costs for ranging hardware. Instead of directly mapping received signal strength values into physical distances, a novel localization scheme with signal-based signature distance estimation is proposed for wireless sensor network. More specifically, we first quantify the near-far relationship between neighbor nodes through received signal strength comparison, and then the distance between non-neighbor nodes is calculated by an improved shortest path algorithm. Based on the obtained node distance, a relative map can be constructed by multidimensional scaling technology. Eventually, the locations of nodes can be acquired by virtue of Procrustes analysis method. For purpose of verifying the effectiveness of our design, several simulations are made in a sensor network with 200 randomly deployed nodes, and two experiments are implemented in real outdoor environments: a linear network and a two-dimensional grid network with 25 nodes. It is remarkable from results that the proposed scheme performs better in positioning and reduces localization errors by as much as 37% compared with state-of-the-art methods. [ABSTRACT FROM AUTHOR]

High quality Er,Yb:CaGdAlO4 (Er,Yb:CALGO) single crystals with a diameter around 1 mm were successfully grown and investigated for the first time by the laser heated pedestal growth (LHPG) method. The cracking mechanism of (001) planes was studied via density functional theory (DFT). The doping concentration of Er3+ and Yb3+ was calculated by X-ray fluorescence analysis (XRF). The XRD pattern confirms that the phase of Er,Yb:CALGO is consistent with pure CALGO and the crystal quality was measured through Laue back-reflection measurements. The optical properties including absorption spectra, mid-infrared fluorescence spectra and fluorescence lifetime of the Er3+, Yb3+ co-doped CALGO crystal were measured at room temperature to assess its potential for improving absorption efficiency. Further research found that the disordered structure of the CALGO crystal could achieve wider absorption and emission bands accompanied with efficient energy transfer from the excited Yb3+ to Er3+. Our results indicated that the Er,Yb:CALGO crystal is a promising material for achieving tunable mid-infrared lasers. [ABSTRACT FROM AUTHOR]

Non‐metal nitrides are an exciting field of chemistry, featuring a significant number of compounds that can possess outstanding material properties. These properties mainly rely on maximizing the number of strong covalent bonds, with crosslinked XN6 octahedra frameworks being particularly attractive. In this study, the phosphorus–nitrogen system was studied up to 137 GPa in laser‐heated diamond anvil cells, and three previously unobserved phases were synthesized and characterized by single‐crystal X‐ray diffraction, Raman spectroscopy measurements and density functional theory calculations. δ‐P3N5 and PN2 were found to form at 72 and 134 GPa, respectively, and both feature dense 3D networks of the so far elusive PN6 units. The two compounds are ultra‐incompressible, having a bulk modulus of K0=322 GPa for δ‐P3N5 and 339 GPa for PN2. Upon decompression below 7 GPa, δ‐P3N5 undergoes a transformation into a novel α′‐P3N5 solid, stable at ambient conditions, that has a unique structure type based on PN4 tetrahedra. The formation of α′‐P3N5 underlines that a phase space otherwise inaccessible can be explored through materials formed under high pressure. [ABSTRACT FROM AUTHOR]

The major challenge to controlling the COVID pandemic is the rapid mutation rate of the SARS-CoV-2 virus, leading to the escape of the protection of vaccines and most of the neutralizing antibodies to date. Thus, it is essential to develop neutralizing antibodies with broad-spectrum activity targeting multiple SARS-CoV-2 variants. Here, we report a synthetic nanobody (named C5G2) obtained by phage display and subsequent antibody engineering. C5G2 has a single-digit nanomolar binding affinity to the RBD domain and inhibits its binding to ACE2 with an IC50 of 3.7 nM. Pseudovirus assays indicated that monovalent C5G2 could protect the cells from infection with SARS-CoV-2 wild-type virus and most of the viruses of concern, i.e., Alpha, Beta, Gamma and Omicron variants. Strikingly, C5G2 has the highest potency against Omicron BA.1 among all the variants, with an IC50 of 4.9 ng/mL. The cryo-EM structure of C5G2 in complex with the spike trimer showed that C5G2 binds to RBD mainly through its CDR3 at a conserved region that does not overlap with the ACE2 binding surface. Additionally, C5G2 binds simultaneously to the neighboring NTD domain of the spike trimer through the same CDR3 loop, which may further increase its potency against viral infection. Third, the steric hindrance caused by FR2 of C5G2 could inhibit the binding of ACE2 to RBD as well. Thus, this triple-function nanobody may serve as an effective drug for prophylaxis and therapy against Omicron as well as future variants. [ABSTRACT FROM AUTHOR]

COVID-19 is currently the biggest threat that challenges all of humankind's health and property. One promising and effective way to control the rapid spreading of this infection is searching for primary close contacts of the confirmed cases. In response, we propose COVID-19 Tracer, a low-cost passive searching system to find COVID-19 patients' close contacts. The main idea is utilizing ubiquitous WiFi probe requests to describe the location similarity, which is then achieved by two designed range-free judgment indicators: location similarity coefficient and close contact distance. We have carried out extensive experiments in a school office building, and the experimental results show an average accuracy of more than 98%, demonstrating our system's effectiveness in judging close contacts. Last but not least, we have developed a prototype system for a school building to find potential close contacts. [ABSTRACT FROM AUTHOR]

Clock synchronization is still a vital and challenging task for underground coal wireless internet of things (IoT) due to the uncertainty of underground environment and unreliability of communication links. Instead of considering on-demand driven clock synchronization, this paper proposes a novel Adaptive Robust Synchronization (ARS) scheme with packets loss for mine wireless environment. A clock synchronization framework that is based on Kalman filtering is first proposed, which can adaptively adjust the sampling period of each clock and reduce the communication overhead in single-hop networks. The proposed scheme also solves the problem of outliers in data packets with time-stamps. In addition, this paper extends the ARS algorithm to multi-hop networks. Additionally, the upper and lower bounds of error covariance expectation are analyzed in the case of incomplete measurement. Extensive simulations are conducted in order to evaluate the performance. In the simulation environment, the clock accuracy of ARS algorithm is improved by 7.85% when compared with previous studies for single-hop networks. For multi-hop networks, the proposed scheme improves the accuracy by 12.56%. The results show that the proposed algorithm has high scalability, robustness, and accuracy, and can quickly adapt to different clock accuracy requirements. [ABSTRACT FROM AUTHOR]

Whether Helicobacter pylori (H. pylori) infection is associated with periodontitis has been contested for decades. The relationship between H. pylori genotypes and periodontitis has not been clarified either. The present study provides a novel perspective to better understand the role of H. pylori in the pathogenesis of periodontitis. A total of 53 volunteers were recruited and divided into 3 groups in this cross-sectional study, namely the periodontally healthy group (15 participants), the stage I/II periodontitis group (20 participants) and the stage III/IV periodontitis group (18 participants). DNA from the subgingival plaque of all participants was extracted and PCR was performed using specific primers for the urease C gene and cytotoxin-associated gene A (cagA)/vacuolating cytotoxin gene A (vacA) to detect the presence and genotype of H. pylori. A χ2 test and one-way ANOVA were performed on the data. There was no significant difference in sex, age or body mass index between the groups. The detection rate of H. pylori was 39.62% in the total population and increased with the deepening of probing depth and clinical attachment loss. There were significant differences in the detection rate of H. pylori among the three groups, with 13.33, 40.00 and 61.11% in the periodontally healthy, stage I/II periodontitis and stage III/IV periodontitis groups, respectively (χ2=8.760, P<0.001). The cagA-/vacAs2m2 genotype was most commonly detected in the periodontally healthy group (100%). In the periodontitis group, cagA+/vacAs1m2 was the most commonly detected genotype in the stage I/II periodontitis group (37.5%) and cagA+/vacAs1m1 in the stage III/IV periodontitis group (36.3%). The results of the present study suggest that the detection rates and genotypes of H. pylori in the subgingival plaque are associated with the status of periodontitis. cagA+/vacAs1m1 and cagA+/vacAs1m2 may be considered virulence markers of periodontitis. However, given the small sample size and lack of correlation analysis of the study, further larger scale and high-quality clinical trials are required to confirm these findings. [ABSTRACT FROM AUTHOR]

Underground personnel localization is highly important in the operations of coal mines. Considering the special underground environment, this paper introduces a novel localization scheme based on step detection and image recognition technologies, which makes use of unique characteristics of the underground environment like the dark environment and the miner's lamp. Since the underground topology is relatively simple, the miner can be located only by step information. However, the localization with step information always causes the problem of cumulative error. To solve this problem, we rebuild a special base station with a camera in a dark underground environment. A miner's lamp, which every miner carries, can simply transform to irradiate unique shapes (such as triangles, rectangles, and circles) and every coal miner at the base station can identify these shapes based on image recognition technologies. Thus, we can obtain the miner's precise position when he/she is passing by a base station. In that way, we can correct the localization results to solve cumulative error. We implemented our algorithm in indoor and underground environments. The experimental results show that 96% of spatial errors were 2.5 m or less. [ABSTRACT FROM AUTHOR]

Invited for the cover of this issue are Dominique Laniel (University of Edinburgh), Florian Trybel (University of Linköping), and their colleagues. The image depicts a bridge built of the newly discovered δ‐P3N5 solid with the structure featuring PN6 units, a previously missing connection between the carbon group elements nitrides and chalcogens nitrides. Read the full text of the article at 10.1002/chem.202201998. [ABSTRACT FROM AUTHOR]

Now, the discovery of the -P SB 3 sb N SB 5 sb and PN SB 2 sb phosphorus nitrides - formed under high pressure and both composed of the elusive PN SB 6 sb octahedron - builds a long-sought-after bridge between these two groups of nitrides. Keywords: high-pressure high-temperature synthesis; non-metal nitrides; PN6 octahedra; synchrotron single-crystal X-ray diffraction; ultra-incompressibility EN high-pressure high-temperature synthesis non-metal nitrides PN6 octahedra synchrotron single-crystal X-ray diffraction ultra-incompressibility 1 1 1 11/10/22 20221107 NES 221107 B For the last 30 years b , the lack of a binary phosphorus nitride containing PN SB 6 sb octahedra formed a scientific chasm between carbon-group and oxygen-group nitrides, both featuring a variety of solids with XN SB 6 sb units (X being a non-metal element). High-pressure high-temperature synthesis, non-metal nitrides, PN6 octahedra, synchrotron single-crystal X-ray diffraction, ultra-incompressibility. [Extracted from the article]

Non‐metal nitrides are an exciting field of chemistry, featuring a significant number of compounds that can possess outstanding material properties. These properties mainly rely on maximizing the number of strong covalent bonds, with crosslinked XN6 octahedra frameworks being particularly attractive. In this study, the phosphorus–nitrogen system was studied up to 137 GPa in laser‐heated diamond anvil cells, and three previously unobserved phases were synthesized and characterized by single‐crystal X‐ray diffraction, Raman spectroscopy measurements and density functional theory calculations. δ‐P3N5 and PN2 were found to form at 72 and 134 GPa, respectively, and both feature dense 3D networks of the so far elusive PN6 units. The two compounds are ultra‐incompressible, having a bulk modulus of K0=322 GPa for δ‐P3N5 and 339 GPa for PN2. Upon decompression below 7 GPa, δ‐P3N5 undergoes a transformation into a novel α′‐P3N5 solid, stable at ambient conditions, that has a unique structure type based on PN4 tetrahedra. The formation of α′‐P3N5 underlines that a phase space otherwise inaccessible can be explored through materials formed under high pressure. [ABSTRACT FROM AUTHOR]