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Objective: Poor fetal and perinatal outcomes in fetuses associated with umbilical artery thrombosis (UAT), such as severe intrauterine growth restriction (IUGR) and intrauterine asphyxia have been reported by some case series. Its hemodynamic impact remains unclear. The aim of this study was to evaluate the hemodynamic changes and perinatal outcome in UAT fetuses with a relatively large sample. Methods: We included singleton fetuses diagnosed with UAT and with at least one available Doppler evaluation before the end of pregnancy in our center from 2016 to 2023. Fetuses with structural abnormalities and with no follow-up results were excluded. Doppler waveforms from the Umbilical artery (UA), middle cerebral artery (MCA), ductus venosus (DV) and uterine artery (UtA) were routinely evaluated according to ISUOG Practice Guidelines from diagnosis. The same sample of GA-matched normal fetuses with Doppler measurements during the same period were randomly selected as control group. Results: Eighty-nine singleton fetuses with UAT with at least one Doppler evaluation before the end of pregnancy were identified, 13 fetuses with no follow-up results were excluded. After comprehensive prenatal counseling, 14 cases received urgent cesarean section, the remaining 55 cases received expectant management, the median day between GA at diagnosis and end of pregnancy was 13 (5–53) days (range, 2-159). 7 (7/76, 9.2%) cases occurred stillbirth, and the incidence of IUGR and Neonatal Intensive Care Unit (NICU) admission were 18.4% (14/76) and 13.2% (10/76) respectively. 49 fetuses (49/76, 64.5%) combined with Doppler abnormalities. UA abnormalities (35/76, 46.1%) and MCA abnormalities (34/76, 44.7%) were the most changes at presentation. Compared to control group, UA-EDV was significantly increased in UAT fetuses [21.84 (15.59–26.64) vs. 16.40 (12.43–20.70) cm/s, p < 0.001], UA-PI and UA-RI significantly decreased [0.68 (0.57–0.84) vs. 0.92 (0.79–1.11), p<0.001; 0.51 (0.44–0.59) vs. 0.62 (0.55–0.68), p < 0.001, respectively]. Both the MCA-PSV and MCA-EDV were significantly higher in UAT fetuses [54.60 (48.00-61.34) vs. 44.47 (29.66–57.60) cm/s, p < 0.001; 11.19 (7.84–17.60) vs. 8.22 (5.21-12.00) cm/s, p < 0.001, respectively], this led to a lower MCA-PI and MCA-RI. Meanwhile, DV-PIV was significantly higher in UAT fetuses [0.6 (0.47–0.87) vs. 0.45 (0.37–0.55), p < 0.001], CPR and UtA-PI were no significant difference between these two groups. Multivariate logistic regression analysis showed that DV-PIV was an independent risk factor for adverse pregnancy outcomes (OR 161.922, p<0.001), the area under the ROC curve (AUC) was 0.792 (95% CI 0.668–0.917; p < 0.001). Conclusion: Our data showed serious adverse pregnancy consequences are combined with UAT fetuses. Hemodynamic changes in UAT fetuses showed the remaining artery for compensation and brain perfusion derangement. With a comprehensive and standardized Doppler evaluation, progression of fetal deterioration may be detailed presented. [ABSTRACT FROM AUTHOR]

Ca-alginate beads have strong hygroscopicity, which have been used for the self-healing and internal curing of cement-based materials. However, ca-alginate beads in cement will chelate with calcium ions, which decreases the swelling rate of ca-alginate beads in the healing environment and is detrimental to the self-healing of cement-based materials. In this paper, the mechanism and steps for preparing ca-alginate beads with a lower ability to chelate with calcium ions were proposed based on protonation theory. In addition, the molecular structure and the swelling rates in cement filtrate and healing environment of ca-alginate beads prepared by the proposed method were characterized. The results showed that the ca-alginate beads prepared by the proposed method had higher molecular density and a lower ability to chelate with calcium ions. The swelling rate in the healing environment is not decreased. Furthermore, the equilibrium swelling rate in cement filtrate can satisfy the need for internal curing of cement-based materials. [ABSTRACT FROM AUTHOR]

A complex network is a useful tool for representing and analyzing complex systems, such as the world-wide web and transportation systems. However, the growing size of complex networks is becoming an obstacle to the understanding of the topological structure and their characteristics. In this study, a globally and locally adaptive network backbone (GLANB) extraction method is proposed. The GLANB method uses the involvement of links in shortest paths and a statistical hypothesis to evaluate the statistical importance of the links; then it extracts the backbone, based on the statistical importance, from the network by filtering the less important links and preserving the more important links; the result is an extracted subnetwork with fewer links and nodes. The GLANB determines the importance of the links by synthetically considering the topological structure, the weights of the links and the degrees of the nodes. The links that have a small weight but are important from the view of topological structure are not belittled. The GLANB method can be applied to all types of networks regardless of whether they are weighted or unweighted and regardless of whether they are directed or undirected. The experiments on four real networks show that the link importance distribution given by the GLANB method has a bimodal shape, which gives a robust classification of the links; moreover, the GLANB method tends to put the nodes that are identified as the core of the network by the k-shell algorithm into the backbone. This method can help us to understand the structure of the networks better, to determine what links are important for transferring information, and to express the network by a backbone easily. [ABSTRACT FROM AUTHOR]

Highlights: Microwave absorber with nanoscale gradient structure was proposed for enhancing the electromagnetic absorption performance. Outstanding reflection loss value (−62.7 dB), broadband wave absorption (6.4 dB with only 2.1 mm thickness) in combination with flexible adjustment abilities were acquired, which is superior to other relative graded distribution structures. This strategy initiates a new method for designing and controlling wave absorber with excellent impedance matching property in practical applications. In the present paper, a microwave absorber with nanoscale gradient structure was proposed for enhancing the electromagnetic absorption performance. The inorganic–organic competitive coating strategy was employed, which can effectively adjust the thermodynamic and kinetic reactions of iron ions during the solvothermal process. As a result, Fe nanoparticles can be gradually decreased from the inner side to the surface across the hollow carbon shell. The results reveal that it offers an outstanding reflection loss value in combination with broadband wave absorption and flexible adjustment ability, which is superior to other relative graded distribution structures and satisfied with the requirements of lightweight equipment. In addition, this work elucidates the intrinsic microwave regulation mechanism of the multiscale hybrid electromagnetic wave absorber. The excellent impedance matching and moderate dielectric parameters are exhibited to be the dominative factors for the promotion of microwave absorption performance of the optimized materials. This strategy to prepare gradient-distributed microwave absorbing materials initiates a new way for designing and fabricating wave absorber with excellent impedance matching property in practical applications. [ABSTRACT FROM AUTHOR]

Abstract: Time series is a very popular type of data which exists in many domains. Clustering time series data has a wide range of applications and has attracted researchers from a wide range of discipline. In this paper a novel algorithm for shape based time series clustering is proposed. It can reduce the size of data, improve the efficiency and not reduce the effects by using the principle of complex network. Firstly, one-nearest neighbor network is built based on the similarity of time series objects. In this step, triangle distance is used to measure the similarity. Of the neighbor network each node represents one time series object and each link denotes neighbor relationship between nodes. Secondly, the nodes with high degrees are chosen and used to cluster. In clustering process, dynamic time warping distance function and hierarchical clustering algorithm are applied. Thirdly, some experiments are executed on synthetic and real data. The results show that the proposed algorithm has good performance on efficiency and effectiveness. [Copyright &y& Elsevier]

Abstract: A horizontal saltation layer of glass particles in air was investigated experimentally in a wind tunnel. Particle concentrations are measured by light scattering diffusion and image processing and all the statistical characteristics were evaluated and thus the probability density function. Our experimental results confirm that the mean concentration decreases exponentially with height, the mean Eulerian dispersion height H being a characteristic lengthscale and that the instantaneous concentration distribution is a random variable following quite well a lognormal distribution. To cite this article: X. Zhang et al., C. R. Mecanique 334 (2006). [Copyright &y& Elsevier]

• Propose a feature grid-based CNN model, FGCN, on traditional data. • Propose methods of converting instance with form of 1-d vector to feature grid. • The performance of FGCN model has reached the state-of-the-art technique XGBoost. • The positions of features in the grid have little influence on prediction accuracy. • Fully connected layers in CNN give little marginal classification performance. Convolutional neural networks (ConvNets) have been applied to various types of data, including image, text, and speech, but not to traditional data. In this study, traditional data are defined as data whose features have no spatial or temporal dependencies but might have statistical correlations. We construct a feature grid-based ConvNet (FGCN) model for classification tasks on traditional data. The FGCN model is composed of two functional parts: The first is used to convert traditional data in the form of a 1-D feature vector into a 1-D, 2-D, or higher-dimensional feature grid; and the second is a ConvNet classifier for the converted data. The experimental results show that the FGCN model performs well; therefore, it is worth considering this model for classification tasks on traditional data. [ABSTRACT FROM AUTHOR]

Due to the high capacity of impurities in its structure, calcite is regarded as one of the most attractive minerals to trap heavy metals (HMs) and radionuclides via substitution during coprecipitation/crystal growth. As a high-reactivity mineral, calcite may release HMs via dissolution. However, the influence of the incorporated HMs and radionuclides in calcite on its dissolution is unclear. Herein, we reported the dissolution behavior of the synthesized calcite incorporated with cadmium (Cd), cobalt (Co), nickel (Ni), zinc (Zn), and uranium (U). Our findings indicated that the HMs and U in calcite could significantly change the dissolution process of calcite. The results demonstrated that the incorporated HMs and U had both inhibiting and enhancing effects on the solubility of calcite, depending on the type of metals and their content. Furthermore, secondary minerals such as smithsonite (ZnCO3), Co-poor aragonite, and U-rich calcite precipitated during dissolution. Thus, the incorporation of metals into calcite can control the behavior of HMs/uranium, calcite, and even carbon dioxide. [ABSTRACT FROM AUTHOR]

Background: Left ventricular non-compaction cardiomyopathy (LVNC) is a rare congenital heart defect. Gene defections have been found in patients with LVNC and their family members; and MYH7 is the most frequent gene associated with LVNC. Methods: We performed a complete prenatal ultrasound and echocardiographic examination on a fetus with cardiac abnormality and a parent–child trio whole-exome sequencing to identify the potential genetic causes. When the genetic abnormality in MYH7 was identified in the fetus, we performed echocardiography and genetic screening on its high-risk relatives. Results: Second trimester ultrasound and echocardiography showed several malformations in the fetus: Ebstein's anomaly (EA), heart dilatation, perimembranous ventricle septal defects, mild seroperitoneum, and single umbilical artery. Heterozygous genotyping of a splicing variant allele (NM_00025.3: c.732+G>A) was identified in this fetus and her mother, not her father, indicating a maternal inheritance. Subsequently, direct sequencing confirmed the presence of this splicing variant among her grandmother (mother of mother), mother, older sister, and herself in a heterozygous manner. No PCR products were amplified by qRT-PCR for the RNA samples extracted from peripheral blood cells. In addition to this proband who was diagnosed with EA, her older sister and grandmother (mother of mother) were diagnosed with isolated asymptomatic LVCN, but her mother was just a carrier with no marked clinical manifestations after family screening. Conclusion: The presence of MYH7 splicing variant c.732+G>A can be inherited maternally, and its cardiac phenotypes are different from one carrier to another. [ABSTRACT FROM AUTHOR]

Calcite is often doped with impurity ions that affect its dissolution behavior. In the present investigation, solid solutions of (Ca, Mn)CO3 and (Ca, Cu)CO3 were synthesized by coprecipitation to study their dissolution in an acidic solution (pH = 5) at 25 °C. The solution chemical analysis results showed that the concentrations of aqueous Cu2+ and Mn2+ first increased and then decreased with the extension of dissolution time. Scanning electron microscope (SEM) and transmission electron microscope (TEM) observations revealed that rhodochrosite (MnCO3) and malachite (Cu2(OH)2CO3) formed during the dissolution. This suggested that the impurities in calcite might impact the dissolution and precipitation of carbonates in the environment. [ABSTRACT FROM AUTHOR]

Tunable Diode Laser Absorption Spectroscopy (TDLAS) has been widely applied in in situ and real-time monitoring of trace gas concentrations. In this paper, an advanced TDLAS-based optical gas sensing system with laser linewidth analysis and filtering/fitting algorithms is proposed and experimentally demonstrated. The linewidth of the laser pulse spectrum is innovatively considered and analyzed in the harmonic detection of the TDLAS model. The adaptive Variational Mode Decomposition-Savitzky Golay (VMD-SG) filtering algorithm is developed to process the raw data and could significantly eliminate the background noise variance by about 31% and signal jitters by about 12.5%. Furthermore, the Radial Basis Function (RBF) neural network is also incorporated and applied to improve the fitting accuracy of the gas sensor. Compared with traditional linear fitting or least squares method (LSM), the RBF neural network brings along the enhanced fitting accuracy within a large dynamic range, achieving an absolute error of below 50 ppmv (about 0.6%) for the maximum 8000 ppmv methane. The proposed technique in this paper is universal and compatible with TDLAS-based gas sensors without hardware modification, allowing direct improvement and optimization for current optical gas sensors. [ABSTRACT FROM AUTHOR]

Single-component white phosphor is highly desirable to obtain efficient and stable white light-emitting diodes (w-LED). In this paper, a series of Bi3+, Tb3+, and Eu3+ doped Ca 3 LuAl 3 B 4 O 15 (CLAB) luminescent materials were successfully prepared. The structure, morphology, and optical properties of samples were characterized by X-ray diffractometer, scanning electronic microscopy, and fluorescence spectroscopy, respectively. The synthesized phosphor exhibits strong blue band emission from Bi3+ and intense characteristics line emission from Tb3+ and Eu3+ under ultraviolet (UV) light excitation. The emission color can fine be adjusted by changing the doping content of the three activators. The warm white light of CLAB:0.5%Bi3+,2%Tb3+,0.75%Eu3+ with CIE chromaticity coordinates of (0.3728,0.3166), a CCT of 3671 K, and a Ra index of 87 could be realized under UV light excitation. The fabricated w-LED by combining UV chip with CLAB:0.5%Bi3+,2%Tb3+,0.75%Eu3+ shows excellent thermal stability after high-temperature aging test, implying its promising application in single-phosphor-converted warm w-LEDs. A single-phosphor-converted warm w-LED fabricated by UV chip with CLAB:Bi3+,Tb3+,Eu3+ shows thermally robust properties. [Display omitted] [ABSTRACT FROM AUTHOR]

An approach for the analysis of atomically resolved scanning transmission electron microscopy data with multiple ferroic variants in the presence of imaging non-idealities and chemical variabilities based on a rotationally invariant variational autoencoder (rVAE) is presented. We show that an optimal local descriptor for the analysis is a sub-image centered at specific atomic units, since materials and microscope distortions preclude the use of an ideal lattice as a reference point. The applicability of unsupervised clustering and dimensionality reduction methods is explored and is shown to produce clusters dominated by chemical and microscope effects, with a large number of classes required to establish the presence of rotational variants. Comparatively, the rVAE allows extraction of the angle corresponding to the orientation of ferroic variants explicitly, enabling straightforward identification of the ferroic variants as regions with constant or smoothly changing latent variables and sharp orientational changes. This approach allows further exploration of the chemical variability by separating the rotational degrees of freedom via rVAE and searching for remaining variability in the system. The code used in this article is available at https://github.com/saimani5/ferroelectric_domains_rVAE. [ABSTRACT FROM AUTHOR]

Systematic transport measurements have been performed on a series of La0.67Ca0.33MnO3 thin films with varying degrees of anisotropic strain. The strain is induced via epitaxial growth on NdGaO3(001) substrates and varied by controlling the thermal annealing time. An antiferromagnetic insulating (AFI) state, possibly associated with charge ordering, emerges upon thermal annealing. The Hall effect in these materials exhibits features that are indicative of a percolative phase transition and correlate closely with the emergence of the AFI state. In the paramagnetic phase, the Hall resistivity takes on two slopes in all samples: a decreasing negative slope with increasing temperature at low fields, which is attributed to the carrier hopping motion, and an almost temperature independent positive slope at high fields due to diffusive transport of holes. Significantly, the crossover fields of the Hall resistivity slope at different temperatures correspond to the same magnetization, which is interpreted as the critical point of a magnetic field-driven percolative phase transition. At lower temperatures near the zero-field metal–insulator transition, pronounced enhancement of the Hall coefficient with the development of the AFI state is observed. The enhancement peaks near the magnetic field-driven percolation; its magnitude correlates with the strength of the AFI state and is suppressed with the melting of the AFI state by an in-plane magnetic field. The observations resemble many features of the enhancement of the Hall coefficient in granular metal films near the composition-driven percolation. [ABSTRACT FROM AUTHOR]

Abstract: The effects of modification by HNO3 oxidization on the physico-chemical properties of activated carbon fiber (ACF), the adsorption of aniline, pyridine and phenol on ACF and modified ACF, as well as the influence of textural properties on adsorption by comparing ACF with an activated carbon are investigated. The adsorbents are characterized using N2 adsorption, Boehm titration, diffuse reflectance infrared Fourier transform spectroscopy, and temperature-programmed desorption. The pore properties of ACF are not significantly changed by the modification; however, it increases greatly the oxygenated acidic groups on the surface of ACF. The uptake for each aromatic compound by the modified ACF is lower than on ACF. This is mainly due to the decrease of dispersive interaction, more water cluster formed to block entry of compounds into micropores or competition between water and compounds adsorbed onto the surface of ACF because of hydrophilic increase of ACF. The maximum uptake for the aromatic compounds decreases with the increase in aqueous solubility of the adsorbates. K, a Langmuir parameter, is indirectly associated with the surface chemistry of ACF. For the aromatic compounds mentioned, the uptake increases with the micropore volume of carbon materials. [ABSTRACT FROM AUTHOR]

Halogenated methyl sulfonic acid (HMSAs) is a new type of disinfection by-product recently reported, and there are few relevant studies, so its source and harm are still unclear. This study mainly discusses the source of halogenated methyl sulfonic acid from the macroscopic level and evaluates the harm to human health. This study clarified that chlorine disinfection is one of the main ways of generating halogenated methyl sulfonic acids (HMSAs) in drinking water. The macroscopic properties of HMSA precursors were analyzed through liquid chromatograph-mass spectrometry (LC-MS/MS), 3D fluorescence, and Fourier transform infrared spectrometry. The results showed that polar and positively charged organic compounds with molecular weights of >3 KDa or <0.5 KDa can readily generate HMSAs. By analyzing the main components of natural organic compounds in water and comparing them with the characteristics of organic compounds such as dimethyl sulfoxide and ethyl mercaptan, it meant that natural organic compounds are easily degraded. Humic and fulvic acids contribute the most to HMSA generation. This study lasted for three years and collected water samples from 102 waterworks in 24 cities in China, and the existence of HMSAs in drinking water in different cities was analyzed. The potential health risks associated with HMSAs were used by the United States Environmental Protection Agency (U.S. EPA) health risk assessment model. The average and maximum concentrations of HMSAs in tap water from key cities in China were taken as evaluation objects. The results showed that the carcinogenic risk coefficient (R) value of both concentrations was far lower than the lowest acceptable carcinogenic risk (1.0 × 10−6) provided by U.S. EPA. Therefore, HMSAs in drinking water in China currently pose no human health risks. • Chlorine disinfection is one of the reasons for the production of halogenated methyl sulfonic acid (HMSAs) in drinking water. • The natural organic matter easy to degrade in water is macro precursor of HMSAs. • Humic acid and fulvic acid are the main factors of HMSAs produced by chlorine disinfection. • HMSAs in drinking water in China has little impact on human health. [ABSTRACT FROM AUTHOR]

Highly luminescent GdVO 4 :Eu3+/carbon dots (CDs) nanocomposite was synthesized by hydrothermal deposition method for the first time. With the use of dialyzed CDs solution as precursor, the synthetized composite shows negligible emission intensity of CDs. On replacing the dialyzed CDs solution with the crude one, highly luminescent composite can be obtained successfully. Based on the analysis of XPS and FT-IR spectra, one can deduce that the existence of a large amount of citrate anions, ethylenediamine cations and polymer-like CDs in the crude CDs solution make it as nutrient solution of CDs, which can not only facilitate growth of CDs on the surface of GVE, but also greatly prevent nitrogen atoms from falling off the particles during the hydrothermal deposition process. For the dialyzed CDs solution, due to the ions and polymer-like CDs being thoroughly dialyzed, the coated CDs are fragile during hydrothermal deposition process. Besides, the effects of different dosages of ammonia on emission intensities of the two composites are studied. Based on the designable patterns for security application, one can think that the highly luminescent composite is one of the most promising candidates in the anti-counterfeiting field. • Highly luminescent GdVO 4 :Eu3+/CDs nanocomposite was synthesized by hydrothermal deposition method. • The hydrothermal deposition method was used to synthesize highly luminescent composite related to CDs for the first time. • The crude CDs solution was used as precursor, which acts as the nutrient solution of N-CDs. • The nutrient solution can not only facilitate growth of CDs on the surface of GVE, but also greatly prevents nitrogen atoms from falling off the particles during hydrothermal deposition process. • The prepared composite is one of the most promising candidates in the anti-counterfeiting field. [ABSTRACT FROM AUTHOR]

Abstract: Aortic coarctation is a life-threatening defect when it occurs with cardiorespiratory failure. Its genetic cause remains unknown. A woman was pregnant twice, both with male fetuses that had partial trisomy 18p, partial monosomy 18q, and aortic coarctation. The syndrome may relate to the aortic coarctation and pulmonary hypoplasia and is life-threatening. ArrayCGH analysis suggested a de novo 17.7Mb deletion of chromosome 18q21.33→qter (58,413,193bp to 76,116,029bp) and a de novo 12.4Mb duplication of chromosome 18pter→p11.21 (1543bp to 12,438,430bp) at the telomeric end of chromosome 18. To the best of our knowledge, the present chromosomal breakpoint with rearrangement has not been previously described. This chromosome aberration may be responsible for this syndrome. [Copyright &y& Elsevier]