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The wet electrostatic precipitator (WESP) overcomes the shortcomings of traditional electrostatic precipitators, such as dust re-entrainment and back corona. It can effectively remove high-specific-resistivity dust, with a good removal effect on PM2.5. It is proposed to adopt chemical agglomeration and humidification agglomeration technology in the wet electrostatic precipitators to achieve ultra-low dust emissions from coal-fired power plants. The results show that the addition of chemical agglomerates, surfactants, and water vapor all affect the dust diameter of coal-fired power plants. After adding sesbania gum (SG), the D50 of dust particles increases from 28.29 μm to 48.22 μm. And the D50 of dust particles is 36.46 μm when spraying 3.6 kg/h water vapor only. With the cooperation of chemical agglomeration agents and water vapor, the dust agglomeration effect and removal efficiency can be further improved. When 10 mg/L SG is synergistically combined with 2.9 kg/h water vapor, the D50 is 64.75 μm, and the dust removal efficiency reaches 97.88%. On this basis, by adding 5 mg/L of Hexadecyltrimethylammonium bromide (CTAB), the D50 is 83.06 μm, and the dust removal efficiency increases to 98.62%. The synergistic effect of chemical agglomeration and humidification agglomeration promotes the aggregation of dust from coal-fired power plants. It can improve the removal efficiency of WESP for fine particulate matter but has little impact on the operation of existing equipment. The synergistic effects of multiple agglomeration technologies are also the direction for future research on the removal efficiency of fine particulate matter. [ABSTRACT FROM AUTHOR]

This article discusses a case of congenital hemangioma (CH) in the breast, accompanied by breast hypoplasia in a 12-year-old girl. CH is a rare cutaneous vascular tumor that develops in utero, and its relationship to breast development is uncertain. The authors suggest surgical intervention for CH in the breast before puberty to promote normal breast development. They emphasize the importance of accurate preoperative identification of CH subtypes and careful surgical dissection to avoid damage to the breast bud. The article calls for more reports on long-term postoperative breast development to evaluate the benefits of early surgical excision. [Extracted from the article]

We report an unusual case of facial infiltrating lipomatosis with hemimegalencephaly and lymphatic malformations. In addition to the clinical data and imaging findings, detection of a heterozygous PIK3CA nonhotspot known pathogenic variant C420R in a facial epidermal nevus provided novel insight into the pathogenic effect of somatic PIK3CA mutations. [ABSTRACT FROM AUTHOR]

The geometric parameters of the deposited layer include the width, height, and penetration depth of the deposited layer. The welding current, wire feeding speed, and torch travel speed during the additive manufacturing process of TC4 titanium alloy have the greatest impact on the geometric parameters of the deposited layer. In order to study how the deposition layer width, deposition layer height, and penetration depth are affected by the welding current, wire feeding speed, and torch travel speed, this article uses Design Expert 8.0.6 software for Box−Behnken design response surface experiments. During the experimental design, the welding current, wire feeding speed, and torch travel speed are used as input variables. The deposition layer width, deposition layer height, and penetration depth are selected as the responses. We designed 17 response surface experiments that were conducted using GTAW-AM. The results show that as the welding current increases, the penetration depth and width of deposition layer gradually increase, and the deposition layer height gradually decreases. As the wire feeding speed increases, the deposition layer height and penetration depth gradually increase, and the wire feeding speed has a minimal effect on the deposition layer width. As the torch travel speed increases, the penetration depth, width and height of deposition layer gradually decrease. The response surface method experimental design can also optimize the matching of three process parameters: welding current, wire feeding speed, and torch travel speed, thereby obtaining the optimal matching range of process parameters. Within the optimized matching range of process parameters, a welding current of 90 A, a wire feeding speed of 900 mm/min, and a torch travel speed of 200.18 mm/min were selected to prepare TC4 titanium alloy thin-walled part. The microstructure of the top, middle and bottom are all basketweave structure. The α phase gradually becomes coarse from the top to the bottom. The microhardness of the top, middle, and bottom of the thin-walled parts is 362.7 HV, 352.7 HV, and 340.5 HV, respectively. The horizontal tensile strength is 926.1 MPa, with an elongation of 12.22%, and the vertical tensile strength is 938.1 MPa, with an elongation of 14.41%. [ABSTRACT FROM AUTHOR]

This study aimed to enhance the efficiency of construction waste bricks (PRBPs) in removing diclofenac (DFC) by preparing surfactant-modified waste bricks (CCBPs) as adsorbents. The properties of the adsorbents were analyzed, and the parameters related to the adsorption process were examined. The findings demonstrate that the addition of cetyltrimethyl ammonium bromide (CTAB) significantly improved the ability of the waste bricks to adsorb DCF. The pH values affected the adsorption behavior, with the adsorption decreasing as the pH increased. The adsorption process followed the pseudo-first-order kinetic equation, and the rate of adsorption was fast. The Langmuir model was used to fit the adsorption isotherms. According to the adsorption thermodynamics, the adsorption of DCF onto both adsorbents was exothermic, and it was more favorable at lower temperatures. The adsorption capacity of the CCBPs decreased sharply as the KCl concentration increased. The mechanism of adsorption might be explained by the interplay of the π-π interaction, surface complexation, and electrostatic interaction. This study offers a new method for removing micropollutants from aqueous solutions using waste bricks, thus extending the scope of their reuse applications. [ABSTRACT FROM AUTHOR]

A wet electrostatic precipitator (WESP) has much higher capture rate for fine particulate matter, PM2.5, than a traditional dry type electrostatic precipitator does. In order to make full use of existing dust removal equipment and reduce the emissions of smoke and dust to zero, a combination of chemical coagulation and humidification coagulation is proposed using a WESP. The results show that the addition of chemical coagulant can promote the coagulation of coal-fired dust particles. After the addition of pectin (PG), the median diameter of dust particles increases from 28.19 μm to 45.28 μm. Water vapor humidification can promote the coagulation of dust particles. When the water vapor injection rate increases from 0 kg/h to 3.2 kg/h, the median diameter of dust particles increases from 28.19 μm to 36.45 μm. The synergistic effect of the coagulant and water vapor can enhance the chemical coagulation effect; when 1.0 × 10−2 g/L PG and 3.2 kg/h water vapor synergize, the collection efficiency reaches 98.17%, and when 1.0 × 10−2 g/L polyacrylamide (PAM) and 3.2 kg/h water vapor synergize, the collection efficiency reaches 96.68%. Both chemical coagulation and water vapor humidification can promote the condensation of coal dust, which is beneficial to improve the efficient capture of fine particles using WESP. [ABSTRACT FROM AUTHOR]

Lanthanum oxide powder was added to improve the microstructure and properties of a Ti-6Al-4V alloy part during cold metal transfer (CMT) based on wire arc additive manufacturing (WAAM). The macrostructure, microstructure and properties of the part were studied by using an optical microscope (OM), scanning electron microscope (SEM), electron backscatter(ed) diffraction (EBSD), microhardness evaluation and a tensile test. The results showed that the β grain size and martensite (α) size were reduced by adding lanthanum oxide powder. The texture intensity of the part also decreased due to the change in microstructure. Accordingly, the microhardness and tensile properties of the part obtained by adding lanthanum oxide were improved. In addition, based on the interdependence theory model, adding La2O3 particles in the molten pool as heterogeneous nucleation points could reduce the distance of XSD, so fine equiaxed β grains can be formed in the deposition layer. [ABSTRACT FROM AUTHOR]

Wet electrostatic precipitators (WESPs) are increasingly used in iron and steel plants and coal-fired power plants due to their higher efficiency at capturing fine particles than conventional dry-type precipitators. In order to achieve ultra-pure purification of dust in steel plant gas, we propose an improved method that involves adding a chemical coagulant and a surfactant to a WESP. The effects of the type and concentration of chemical coagulant and surfactant on the agglomeration effect and dust removal efficiency of blast furnace dust were investigated. The results show that the addition of a chemical coagulant could promote the agglomeration of blast furnace dust particles, and the D50 of dust particles increased from 5.8 to 15.0 μm after the addition of xanthan gum (XTG). The best increase in the blast furnace's dust particle removal occurred at a concentration of 10 mg/L of XTG, and the dust removal efficiency reached 97.59%. The surfactant dodecyl trimethyl ammonium chloride (DTAC) improved the dust removal efficiency of blast furnace dust when added alone. The dust removal efficiency reached 97.82% when 10 mg/L of XTG and 9 mg/L of DTAC were added synergistically. The addition of a chemical coagulant and surfactant promoted the agglomeration of blast furnace dust and enhanced the dust capture effect of a WESP. We thus demonstrated that we can improve the efficiency of WESP in the future via chemical coagulation. The authors will further study the effect of multi-factor synergistic coupling on the chemical coagulation method in WESPs. [ABSTRACT FROM AUTHOR]

Gemini amphiphile is a special type of block copolymers formed by connecting two traditional diblock molecules at hydrophilic head groups through spacers. The special structure makes gemini amphiphiles potentially promising for drug delivery and gene delivery. The self‐assembly behavior of gemini amphiphiles with tails of equal length in selective solvent was investigated using the dissipative particle dynamics method. The effects of the size of the hydrophilic head group, interaction parameters, concentration and hydrophobic tail chain length on the self‐assembled morphology of gemini amphiphiles were examined. By varying these parameters, worm‐like micelles, large compound micelles, vesicles, hierarchical rod‐like micelles, cylindrical bundles, pomegranate‐like micelles and bilayers were obtained. Compared with conventional diblock copolymers, the dominant feature of gemini amphiphiles is the presence of the spacer. By analyzing the distance between two head groups, we explored in depth the influence of spacer length on the self‐assembly of gemini amphiphile molecules. Through simulation probes, we hope to improve the understanding of ordered aggregates of gemini amphiphiles in selective solvent, to reveal theoretically the pattern variation of aggregation morphology and to provide guidance for their practical application. © 2022 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

Early blight and late blight are important factors restricting tomato yield. However, it is still a challenge to accurately and objectively detect and segment crop diseases in order to evaluate disease damage. In this paper, the Disease Segmentation Detection Transformer (DS-DETR) is proposed to segment leaf disease spots efficiently based on several improvements to DETR. Additionally, a damage assessment is carried out by the area ratio of the segmented leaves to the disease spots. First, an unsupervised pre-training method was introduced into DETR with the Plant Disease Classification Dataset (PDCD) to solve the problem of the long training epochs and slow convergence speed of DETR. This method can train the Transformer structures in advance to obtain leaf disease features. Loading the pre-training model weight in DS-DETR can speed up the convergence speed of the model. Then, Spatially Modulated Co-Attention (SMCA) was used to assign Gaussian-like spatial weights to the query box of DS-DETR. The different positions in the image are trained using the query boxes with different weights to improve the accuracy of the model. Finally, an improved relative position code was added to the Transformer structure of DS-DETR. Relative position coding promotes the capture of the sequence order of input tokens by the Transformer. The spatial location feature is strengthened by establishing the location relationship between different instances. Based on these improvements, the DS-DETR model was tested on the Tomato leaf Disease Segmentation Dataset (TDSD) constructed by us. The experimental results show that the DS-DETR proposed by us achieved 0.6823 for APmask, which improved by 12.87%, 8.25%, 3.67%, 1.95%, 10.27%, and 9.52% compared with the state-of-the-art: Mask RCNN, BlendMask, CondInst, SOLOv2, ISTR, and DETR, respectively. In addition, the disease grading accuracy reached 0.9640 according to the segmentation results given by our proposed model. [ABSTRACT FROM AUTHOR]

Carbapenem-resistant Klebsiella pneumoniae (CRKP), a pathogen that causes severe nosocomial infections and yields a high mortality rate, poses a serious threat to global public health due to its high antimicrobial resistance. Bacteriophages encode polysaccharide-degrading enzymes referred to as depolymerases that cleave the capsular polysaccharide (CPS), one of the main virulence factors of K. pneumoniae. In this study, we identified and characterized a new capsule depolymerase K19-Dpo41 from K. pneumoniae bacteriophage SH-KP156570. Our characterization of K19-Dpo41 demonstrated that this depolymerase showed specific activities against K19-type K. pneumoniae. K19-Dpo41-mediated treatments promoted the sensitivity of a multidrug-resistant K19-type K. pneumoniae strain to the bactericidal effect of human serum and significantly increased the survival rate of Galleria mellonella infected with K19-type K. pneumoniae. Our results provided strong primary evidence that K19-Dpo41 was not only effective in capsular typing of K19-type K. pneumoniae but promising in terms of developing new alternative therapeutic strategies against K19-type CRKP infections in the future. [ABSTRACT FROM AUTHOR]

The number of wheat spikes per unit area is one of the most important agronomic traits associated with wheat yield. However, quick and accurate detection for the counting of wheat spikes faces persistent challenges due to the complexity of wheat field conditions. This work has trained a RetinaNet (SpikeRetinaNet) based on several optimizations to detect and count wheat spikes efficiently. This RetinaNet consists of several improvements. First, a weighted bidirectional feature pyramid network (BiFPN) was introduced into the feature pyramid network (FPN) of RetinaNet, which could fuse multiscale features to recognize wheat spikes in different varieties and complicated environments. Then, to detect objects more efficiently, focal loss and attention modules were added. Finally, soft non-maximum suppression (Soft-NMS) was used to solve the occlusion problem. Based on these improvements, the new network detector was created and tested on the Global Wheat Head Detection (GWHD) dataset supplemented with wheat-wheatgrass spike detection (WSD) images. The WSD images were supplemented with new varieties of wheat, which makes the mixed dataset richer in species. The method of this study achieved 0.9262 for mAP50, which improved by 5.59, 49.06, 2.79, 1.35, and 7.26% compared to the state-of-the-art RetinaNet, single-shot multiBox detector (SSD), You Only Look Once version3 (Yolov3), You Only Look Once version4 (Yolov4), and faster region-based convolutional neural network (Faster-RCNN), respectively. In addition, the counting accuracy reached 0.9288, which was improved from other methods as well. Our implementation code and partial validation data are available at https://github.com/wujians122/The-Wheat-Spikes-Detecting-and-Counting. [ABSTRACT FROM AUTHOR]

In this study, to investigate the elimination of micropollutant from aqueous solutions by construction waste, waste red brick (WRB) with and without incorporated of iron species (goethite and hematite) were prepared by a simple method. The prepared materials were systematically characterized and batch experiments were conducted to study the elimination of typical micropollutant cimetidine from the water environment. Results showed that both two iron species could be successfully incorporated onto WRB and the main structure of WRB were maintained. The adsorption process of cimetidine onto bricks was fast due to the microstructure and useful adsorption sites on the surface of bricks. The Langmuir model fitted the experimental data better and the qmax of cimetidine increased about 24.4% and 39.6% for the incorporation of hematite and goethite, respectively. The pH values influenced the adsorption behavior greatly and the favorable pH value was around 6.0. The charge screening effect and competition adsorption may influence the adsorption behavior together. Due to the interaction between cimetidine and bricks, the outer-sphere complexation may be formed in the adsorption process. This study shows new methods for the elimination of the micropollutant from the water environment and offers useful guidelines for the reuse of construction waste. [ABSTRACT FROM AUTHOR]

Developing high-strength hydrogels with biocompatibility and bone conductibility is still desirable for bone regeneration. The nanohydroxyapatite (nHA) was incorporated into a dopamine-modified gelatin (Gel-DA) hydrogel system to create a highly biomimetic native bone tissue microenvironment. In addition, to further increase the cross-linking density between nHA and Gel-DA, nHA was functionalized by mussel-inspired polydopamine (PDA). Compared with nHA, adding polydopamine functionalized nHA (PHA) increased the compressive strength of Gel-Da hydrogel from 449.54 ± 180.32 kPa to 611.18 ± 211.86 kPa without affecting its microstructure. Besides, the gelation time of Gel-DA hydrogels with PHA incorporation (GD-PHA) was controllable from 49.47 ± 7.93 to 88.11 ± 31.18 s, contributing to its injectable ability in clinical applications. In addition, the abundant phenolic hydroxyl group of PHA was beneficial to the cell adhesion and proliferation of Gel-DA hydrogels, leading to the excellent biocompatibility of Gel-PHA hydrogels. Notably, the GD-PHA hydrogels could accelerate the bone repair efficiency in the rat model of the femoral defect. In conclusion, our results suggest the Gel-PHA hydrogel with osteoconductivity, biocompatibility, and enhanced mechanical properties is a potential bone repair material. [ABSTRACT FROM AUTHOR]