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An experiment was conducted on the Qingtu Lake Observation Array (QLOA) to measure wind and dust information at various wall-normal heights during the sand and dust storm (SDS) process. According to the indicators of the non-stationary features in the flow field, the SDS process can be divided into three stages: ascending, stabilizing, and descending. Based on this division, the Hilbert–Huang transform (HHT) is employed to extract dominant flow structures, which carries a significant portion of the turbulent kinetic energy. Moreover, the HHT spectrum of stream-wise velocity component reveals that the scales of the dominant structures are approximately hundreds of meters in the horizontal direction, and hence suggests the presence of large and very large-scale coherence during the SDS. The hypotheses of Townsend [The Structure of Turbulent Shear Flow (Cambridge University Press, 1976)] and Davenport ["The spectrum of horizontal gustiness near the ground in high winds," Q. J. R. Meteorol. Soc. 87, 194–211 (1961)] are utilized to demonstrate the vertical coherence of turbulence, which suggests the wall-similarity and evolution of inner/outer interactions for coherent structures during the SDS. Finally, the coherence spectrum [ γ L 2 = exp (− 2 c 1 Δ z / λ x) ] and the linear transfer kernel [ | H L 2 | = exp (d 1 − d 2 Δ z / λ x) ] are parameterized, where c 1 , d 1 , d 2 are fitting parameters, Δ z is wall-normal offset, and λx refers to streamwise wavelength, to illustrate the evolution of the interactions between near-wall and outer regions during the SDS, which highlights the strong connections during the stabilizing stage. In general, the present study analyzed horizontal and wall-normal structures for a comprehensive SDS process, and thus, these findings present abundant features of wall-attached eddies which further be used to improve/enrich existing near-wall models. [ABSTRACT FROM AUTHOR]

The goal of the following study is to clarify whether the skeletal remains over 70 years old from missing persons and their alleged relatives shared identical Y-STR loci. Nowadays, advances in ancient DNA extraction techniques and approaches of using multiple different Y-STRs have significantly increased the possibility of obtaining DNA profiles from highly degraded skeletal remains. Given the ages and conditions of the skeletal remains, ancient DNA extraction methods can be used to maximize the probability of DNA recovery. Considering that information about distant relatives is more relevant for long-term missing persons and alleged family members are male, Y-STR loci analysis is considered the most appropriate and informative approach for determining paternal lineage relationship. In this study, Y-STR genotypes obtained from these alleged relatives were identical to each other and to the alleles of missing persons' consensus profiles at more than 22 loci examined, whilst not being found in Y-STR population database from Y-Chromosome STR Haplotype Reference Database. Therefore, Missing Person No.7 and Missing Person No.18 have a patrilineal relationship with reference samples from Family1 and Family2, respectively. In addition, the fact that Y-STR haplotypes obtained from skeletal remains of missing persons and reference samples are not found in the Han Chinese people from East Asian demonstrates its rarity and further supports a paternal lineage relationship amongst them. [ABSTRACT FROM AUTHOR]

With the recent advances in machine learning, strategies based on data can be used to augment wall modeling in the turbulent boundary layer. Combined with the attached eddy hypothesis, the present work applies extreme gradient boosting (XGBoost) to predict the large-scale wall-attached structures at a range of wall-normal locations based on a near-wall reference position ( z R + ≈ 4) spanning a Reynolds-number range R e τ ∼ O (10 3) − O (10 5). The input and output signals are selected as the large-scale structures; here, the input signals are set as in the fixed near-wall reference position by a series of streamwise velocity ({ X − N , ... , X − 1 , X 0 , X 1 , ... , X N }), and the output signal Y 0 is set directly above X 0 . Within each dataset, the large-scale wall-attached structures are identified from the prediction modeled by XGBoost between the turbulence in the upper region and at the near-wall reference position, resulting in a successful prediction of the large-scale structures inclination angles. Along the wall-normal offset Δ z and streamwise offset L x (distance between X i and X 0 ), the slope of the feature importance (represented by contour levels) is exactly equal to the degree of inclination of large-scale structures, indicating the turbulent inner and outer connection inferred by the machine learning input and output interactions perspective. This study shows that there is a great opportunity in machine learning for wall-bounded turbulence modeling by connecting the flow interactions between near-wall and outer regions. [ABSTRACT FROM AUTHOR]

The auxin/indole-3-acetic acid (Aux/IAA) and auxin response factor (ARF) genes are two crucial gene families in the plant auxin signaling pathway. Nonetheless, there is limited knowledge regarding the Aux/IAA and ARF gene families in Populus simonii. In this study, we first identified 33 putative PsIAAs and 35 PsARFs in the Populus simonii genome. Analysis of chromosomal location showed that the PsIAAs and PsARFs were distributed unevenly across 17 chromosomes, with the greatest abundance observed on chromosomes 2. Furthermore, based on the homology of PsIAAs and PsARFs, two phylogenetic trees were constructed, classifying 33 PsIAAs and 35 PsARFs into three subgroups each. Five pairs of PsIAA genes were identified as the outcome of tandem duplication, but no tandem repeat gene pairs were found in the PsARF family. The expression profiling of PsIAAs and PsARFs revealed that several genes exhibited upregulation in different tissues and under various stress conditions, indicating their potential key roles in plant development and stress responses. The variance in expression patterns of specific PsIAAs and PsARFs was corroborated through RT-qPCR analysis. Most importantly, we instituted that the PsIAA7 gene, functioning as a central hub, exhibits interactions with numerous Aux/IAA and ARF proteins. Furthermore, subcellular localization findings indicate that PsIAA7 functions as a protein localized within the nucleus. To conclude, the in-depth analysis provided in this study will contribute significantly to advancing our knowledge of the roles played by PsIAA and PsARF families in both the development of P. simonii tissue and its responses to stress. The insights gained will serve as a valuable asset for further inquiries into the biological functions of these gene families. [ABSTRACT FROM AUTHOR]

Although scaling laws and coherent structures have been well-studied in non-neutral boundary layer flows over a long period of time, a potential connection between them is still worth exploring. This work explores the structure inclination angle under non-neutral stratification conditions by way of a connection between turbulent scaling and Monin–Obukhov similarity theory. A model for theoretical structure inclination angles is built by extending the refined "turbulent eddy" model of H.-J. Huang [Phys. Rev. Fluids 4, 114702 (2019)] under stratified stability conditions. The variations in the inclination angle values with the stability parameter from the current model are found to be in good agreement with results from the literature, laboratory results, and atmospheric surface layer observations. In addition, the results show that increasing positive/negative buoyancy leads to increasing/decreasing inclination angles and steeper/moderate angles at higher wall-normal heights. This variation is parameterized and can be used to improve existing near-wall models. [ABSTRACT FROM AUTHOR]

Investigating interactions between large- and small-scale motions is essential for understanding turbulence over rough boundaries. The present work applies XGBoost models to predict the spatial distribution of ejections and sweeps and quantify their statistical dependence on scale-decomposed velocity fields. Based on large eddy simulation, the models are trained and validated at 20 horizontal planes in turbulence over two types of obstacle arrays. At each height, a default XGBoost model X0 and four comparison models ( X u L , w L , X u L , w S , X u S , w L , and X u S , w S ) are trained. The model X0 is trained by the set with four scale-decomposed velocity fields { u L , u S , w L , w S } , where u and w are the streamwise and vertical velocity fluctuations and subscripts L and S refer to above-canyon and sub-canyon scales, while the comparison models are trained by subsets of the scale-decomposed velocity fields. The results indicate that the model X0 predicts the spatial distributions of both ejection and sweep events well, with the structure underestimation being less than 8% within the canopy layer and 3% above it. Along the vertical direction, the relative importance of scale-decomposed velocity fields on the prediction of ejections and sweeps is quantified by the feature importance and prediction errors. The feature importance profiles reveal that both sweeps and ejections are most strongly related to w S within the canopy, but ejections have a stronger dependence on u L well above the canopy. For the comparison models, those trained with w S (namely, X u L , w S and X u S , w S ) give better predictions within the canopy layer, whereas those trained with u L (namely, X u L , w S and X u L , w L ) perform better above the canopy. This study shows that a machine-learning-based approach can be designed to quantify the relative importance of different scale-decomposed velocity fields on predicting ejections and sweeps and to detect vertical changes of such relative importance. [ABSTRACT FROM AUTHOR]

Regenerative braking can extend the driving range and reduce PM emissions from abrasion for battery electric heavy-duty trucks (BETs). The composite braking control strategy including torque distribution and dynamic coordinated control for the four-axle BET equipped with the electromechanical braking system is studied. A segmented torque distribution strategy is proposed to maximize energy recovery while ensuring braking stability. The simulation results reveal that the strategy shows better comprehensive braking performance than the two benchmark strategies, and the energy recovery rate in different load states under CHTC-D is above 40%. The proposed coordinated control strategy takes advantage of regenerative braking's rapid response and precise control to compensate for torque deviations caused by the hysteresis of friction braking. For two common braking mode transition conditions, regenerative braking torque correction and advance of the mode switching timing are adopted to enable the motor to obtain the torque compensation ability. This method leads to a slight loss of braking energy, and the maximum torque deviation during the mode switching process is suppressed to less than 1.4 kN·m, and the jerk and braking distance is reduced accordingly, which is of great importance in improving driving comfort and braking safety. [ABSTRACT FROM AUTHOR]

Rainwater infiltration is primarily governed by the soil-water characteristic curve (SWCC) and hydraulic conductivity function (HCF) of soil. Both the SWCC and the HCF are hysteretic during the drying and wetting processes. In a numerical simulation, different seepage results can be obtained by incorporating different hydraulic conductivity functions of soil. In practice, the wetting HCF is commonly estimated from the wetting SWCC using the statistical method, which is named HCFswcc,w in this note. However, there is no study that has verified the results from seepage analyses using HCFswcc,w. Therefore, the objective of this study is to investigate the influence of wetting SWCC and wetting HCF on 1-D water infiltration. The results from the numerical simulations were verified with the instrumentation reading from a soil column. It was observed that the results from the model using wetting HCFPSDF, which defines the wetting HCF estimated using the concept of pore-size distribution function, gave better agreement with the instrumented data. Therefore, both wetting SWCC and wetting HCFPSDF are advised to be used as input information for the numerical simulation of rainwater infiltration. [ABSTRACT FROM AUTHOR]

The aim of this paper is to solve the problem for battery electric vehicles of low-precision and time-consuming inspection. A novel method of driving cycle development for battery electric vehicles' operational safety is proposed in this paper. First, three inspection items are proposed based on relevant testing standards. The inspection calculation method of operational safety is developed based on the acceleration changing rate. Then the multi-cycle inspection method with the stable pedal mode is developed, and the Gauss filtering algorithm is applied for data preprocessing. A rapid inspection driving cycle construction method based on support vector machine is proposed, and a driving cycle is built with a total time of 204 s by fusing and splicing kinematic fragments. Finally, the proposed inspection calculation method is used to validate the operational safety inspection items by tracking the established rapid inspection driving cycle based on the test bench. The results shown are those that qualified the range of acceleration changing rate for driving stability [−0.35, −0.04]. The range for gliding smoothness is [0.05, 0.09]. The range for braking coordination is [−0.04, 0.095]. The maximum RMSE between the constructed rapid inspection segments is 9%, and the maximum RMSE between the tested driving segments is 6%. Test results meet design requirements. The thresholds for operational safety inspection items are evaluated based on the test results. We set less than 0.5 as the safety threshold for driving stability. During the experiment, gliding was less than 0.1 as the safety threshold for gliding comfort, and during braking it was less than 0.1 as the safety threshold for vehicle braking coordination. [ABSTRACT FROM AUTHOR]

However, the corresponding HT ht shows a complex HT ht dependence. One reason to choose this location is to avoid the influence of human activities; e.g., the nearest city is around HT ht HT ht from this observation site; see the geolocation indicated in Fig. b. Dust weather in the Hexi Corridor is often caused by intense frontal systems. It first increases logarithmically with HT ht and reaches its peak, e.g., HT ht m at A, then decreases roughly logarithmically with HT ht . This is partially due to the influence of the ground that the scaling exponent HT ht demonstrates as height dependence. [Extracted from the article]

Electrical injury is a relatively uncommon but potentially devastating form of multi-system injury with high morbidity and mortality. In common electric injury cases, it is usually difficult to find characteristic changes of electric injury in major organs by using routine histopathological test methods unless there are landmark traces of electric injury, known as electric marks. How to determine electric shock death, especially in the absence of typical electrical marks on the body surface in some cases (which account for about two-thirds of electric injury cases), remains a challenging problem in forensic practice. Our summary shows that many current related studies have focused their efforts to find characteristic histopathological changes in major organs of the body caused by electric injury. Based on the results obtained through comparison of the literature, we find that it may be more urgent and important to find the optimal autopsy or sampling sites in cases with no typical electric marks, knowing that these sites may often reflect the most significant histopathological changes of electric injury, for instance anatomy and sampling of the anterior wrist and the medial malleolus in cases involving the hand-to-foot electric circuit pathway. In this article, we make a summary of advances in identification methods of electric injury, hoping that it could provide some new insights for further research in this field. [ABSTRACT FROM AUTHOR]

The present work explores the spanwise logarithmic decay of the turbulence intensity for wall-attached eddies per Townsend's attached eddy hypothesis. Within the dataset spanning a friction Reynolds number range R e τ ∼ O (10 3) − O (10 6) , the coherence between the turbulence in the logarithmic region along the spanwise direction and that at a near-wall reference location is used to assess the scale-dependent coherence. Linear coherence spectrum analysis is applied as a filter to separate the coherent and incoherent portions. After this separation procedure, the turbulence intensity decay for wall-attached eddies in the spanwise direction is described in a log-linear manner, which also identifies how the scaling parameter increases with the Reynolds number. This variation is parametrized and consequently can be used to improve existing near-wall models. [ABSTRACT FROM AUTHOR]

A field experiment was carried out on a dry flat bed of Qingtu Lake in Minqin, China to measure the velocity and temperature in the atmospheric surface layer at high Reynolds number. The facility, the Qingtu Lake Observation Array, permits synchronous multi-point measurements of three-dimensional wind velocity and temperature at different wall-normal and spanwise positions. Data were selected to analyze the characteristics of the large-scale coherent structures under different stratification stability conditions. The results confirm the previous findings that the positive buoyancy can be considered as a wall-normal force to have a "lifting" effect increasing the size of large-scale structures and further illustrate that negative buoyancy in the stable condition has an opposite effect leading to small structures with less wall-normal coherence. The stability dependence of structure inclination angles for all three velocity components is built by a parametric model indicating a log-linear trend under near-neutral and unstable conditions. In addition, the unique measurement array at this facility also permits us to study the three-dimensional form of these features and the associated temperature fluctuations. By computing the space average for momentum and heat flux, we found that the threshold stability parameter z / L = − 0.1 , where z = 2.5 m and L is the Obukhov length scale, can act as a role to determine the dominant flow by shear-driven and buoyancy-driven, respectively. Last, the streamwise length scales for temperature component are investigated where a smaller length scale corresponds to a stronger buoyancy condition, but with larger values at higher heights. [ABSTRACT FROM AUTHOR]

Purpose: This study was designed to expound the underlying mechanism of microtubule-directed chemotherapeutic drugs resistance induced by cancer-associated fibroblasts (CAFs) in breast cancer. Materials and methods: We collected 10 microtubule-directed chemotherapeutic drugs resistant breast tumor samples and 10 normal breast tumor samples to analyze the CAFs distribution by immunohistochemistry and flow cytometry. We also detected the collagen expression in CAFs by real-time PCR. We detected the activation of PI3K/AKT signaling pathway in tumor cells by Western blotting and immunofluorescence. The subcutaneous 4T1/MCF-7 bearing mice were used to investigate the anticancer effects of integrin β1 inhibitor combined with microtubule-directed chemotherapeutic drugs. Results: In our studies, accumulation of CAFs was observed in tumor samples from microtubule-directed chemotherapeutic drugs resistant patients. Those isolated CAFs could efficiently induce the acquisition of microtubule-directed chemotherapeutic drugs resistance in breast cancer cells. More importantly, we found that CAFs could regulate the microtubule-directed chemotherapeutic drugs resistance through the secretion of collagen to activate the integrin β1/PI3K/AKT signaling pathway. Combination of integrin α2β1 inhibitor and paclitaxel/vincristine sulfate could efficiently overcome the microtubule-directed chemotherapeutic drugs resistance induced by CAFs and enhanced the anticancer effects of chemotherapy in subcutaneous 4T1/MCF-7 bearing mice. Conclusion: Our results demonstrated that CAFs constitute a supporting niche for cancer drug resistance acquisition. Thus, traditional microtubule-directed chemotherapeutic drugs combined with integrin β1 inhibitor may present an innovative therapeutic strategy for breast cancer therapy. [ABSTRACT FROM AUTHOR]

Accurate knowledge of the contacts between surface roughness and the resultant wind speed are important for climatic models, wind power meteorology, agriculture and erosion hazards especially on sand saltation in arid and semi‐arid environments, where vegetation cover is scarce. In this study, synchronous measurements of three‐dimensional wind speed below 5 m are carried out in three different surface roughness conditions in Minqin, China, and the difference in the turbulence statistics and the structure of the very large‐scale motions (VLSMs) were revealed. The results show that the slope of the mean wind profile (MVP), the turbulent kinetic energy (TKE) and Reynolds stress increase with the surface roughness. The roughness seems to suppress the ejection events and the surface roughness will not only weaken the energy of the VLSMs, but also reduce the scale values of VLSMs near the wall. These influences may cause some changes regarding the dust transportation in streamwise and vertical directions during the sand and dust storm (SDS). That is, the decrease of the mean velocity near the ground will reduce the dust transportation in the streamwise direction and influence of the roughness on the ejection and sweep events will change the dust transportation in the vertical direction. Furthermore, the increase of roughness will weaken the scale and energy of VLSMs, which will lead to the decrease of the capacity of dust transportation. © 2019 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Traditional Chinese Marine Medicine (TCMM) represents one of the medicinal resources for research and development of novel anticancer drugs. In this study, to investigate the presence of anticancer activity (AA) displayed by cold or hot nature of TCMM, we analyzed the association relationship and the distribution regularity of TCMMs with different nature (613 TCMMs originated from 1,091 species of marine organisms) via association rules mining and phylogenetic tree analysis. The screened association rules were collected from three taxonomy groups: (1) Bacteria superkingdom, Phaeophyceae class, Fucales order, Sargassaceae family, and Sargassum genus; (2) Viridiplantae kingdom, Streptophyta phylum, Malpighiales class, and Rhizophoraceae family; (3) Holothuroidea class, Aspidochirotida order, and Holothuria genus. Our analyses showed that TCMMs with closer taxonomic relationship were more likely to possess anticancer bioactivity. We found that the cluster pattern of marine organisms with reported AA tended to cluster with cold nature TCMMs. Moreover, TCMMs with salty-cold nature demonstrated properties for softening hard mass and removing stasis to treat cancers, and species within Metazoa or Viridiplantae kingdom of cold nature were more likely to contain AA properties. We propose that TCMMs from these marine groups may enable focused bioprospecting for discovery of novel anticancer drugs derived from marine bioresources. [ABSTRACT FROM AUTHOR]

• CACTD is a life-threatening autosomal recessive fatty acid β-oxidation disorder caused by gene mutation. • We describe a rare case with a compound heterozygote with c.199–10 T > G and a novel c.1A > T mutation in SLC25A20 gene. This gene mutation poses a high risk of sudden death. • CACTD is often asymptomatic or with only some nonspecific symptoms, which increases the possibility of misdiagnosis and medical disputes due to unexpected sudden death of the patient. • Extensive vacuolar degeneration was often observed in the heart and liver at autopsy and histopathological examination. However, gene mutation detection is the gold standard for diagnosis of CACTD. Carnitine-acylcarnitine translocase deficiency (CACTD) is a rare and life-threatening autosomal recessive disorder of fatty acid β-oxidation (FAO). Most patients with CACTD develop severe metabolic decompensation which deteriorates progressively and rapidly, causing death in infancy or childhood. As CACTD in some patients is asymptomatic or only with some nonspecific symptoms, the diagnosis is easy to be ignored, resulting in sudden death, which often triggers medical disputes. Herein, we report a case of neonatal sudden death with CACTD. The neonate showed a series of severe metabolic crisis, deteriorated rapidly and eventually died 3 days after delivery. Tandem mass spectrometry (MS-MS) screening of dry blood spots before death showed that the level of long-chain acylcarnitines, especially C12-C18 acylcarnitine, was increased significantly, and therefore a diagnosis of inherited metabolic disease (IMD) was suspected. Autopsy and histopathological results demonstrated that there were diffuse vacuoles in the heart and liver of the deceased. Mutation analysis revealed that the patient was a compound heterozygote with c.199–10 T > G and a novel c.1A > T mutation in the SLC25A20 gene. Pathological changes such as heart failure, arrhythmia and cardiac arrest related to mitochondrial FAO disorders are the direct cause of death, while gene mutation is the underlying cause of death. [ABSTRACT FROM AUTHOR]