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Reliable pseudo-labels from unlabeled data play a key role in semi-supervised object detection (SSOD). However, the state-of-the-art SSOD methods all rely on pseudo-labels with high confidence, which ignore valuable pseudo-labels with lower confidence. Additionally, the insufficient excavation for unlabeled data results in an excessively low recall rate thus hurting the network training. In this paper, we propose a novel Low-confidence Samples Mining (LSM) method to utilize low-confidence pseudo-labels efficiently. Specifically, we develop an additional pseudo information mining (PIM) branch on account of low-resolution feature maps to extract reliable large-area instances, the IoUs of which are higher than small-area ones. Owing to the complementary predictions between PIM and the main branch, we further design self-distillation (SD) to compensate for both in a mutually-learning manner. Meanwhile, the extensibility of the above approaches enables our LSM to apply to Faster-RCNN and Deformable-DETR respectively. On the MS-COCO benchmark, our method achieves 3.54% mAP improvement over state-of-the-art methods under 5% labeling ratios.

Due to the hydrophilic nature of paper mulch, it is easy to absorb water during use, which will reduce its mechanical properties and durability, thus affecting its performance. Therefore, the development of paper mulch is hindered. In this paper, in order to improve the hydrophobic performance of paper mulch, we successfully prepared superhydrophobic silicon dioxide/paper mulch by simple, efficient and environmentally friendly solution immersion method without the introduction of adhesive. The contact Angle and rolling Angle between the prepared super hydrophobic paper mulch and water are 156.4° and 1.8°, respectively. The water drop is easy to roll on its surface, and has excellent water drop bouncing performance, which can play an excellent water-repellent function. Studies have shown that the superhydrophobicity of silicon dioxide/paper mulch is less affected by its surface roughness, mainly because the surface covered by a layer of silicon dioxide reduces the surface energy of the paper mulch, and the silicon dioxide on the surface of the paper mulch is enough to reduce the damage of aging on the paper mulch. In addition, the decrease in the contact angle of the SiO2/paper mulch and the increase in the rolling angle after aging are due to the decrease in the amount of SiO2 adhesion on the surface of the paper mulch and the increase in the degree of exposure of fiber bundles. Studies have found that the superhydrophobic paper mulch can reduce the influence of its own aging on its rolling angle after being subjected to friction.

Superoxide dismutases (SODs) play an important role in protecting plants against ROS toxicity induced by biotic and abiotic stress. Recent studies have shown that the SOD gene family is involved in plant growth and development; however, knowledge of the SOD gene family in tobacco is still limited. In the present study, the SOD gene family was systematically characterized in the tobacco genome. Based on the conserved motif and phylogenetic tree, 15 NtSOD genes were identified and classified into three subgroups, including 5 NtCSDs, 7 NtFSDs and 3 NtMSDs. The predicted results of the transport peptide or signal peptide were consistent with their subcellular localization. Most NtSOD genes showed relatively well-maintained exon-intron and motif structures in the same subgroup. An analysis of cis-acting elements in SOD gene promoters showed that NtSOD expression was regulated by plant hormones, defense and stress responses, and light. In addition, multiple transcription factors and miRNAs are predicted to be involved in the regulation of NtSOD gene expression. The qPCR results indicated specific spatial and temporal expression patterns of the NtSOD gene family in different tissues and developmental stages, and this gene family played an important role in protecting against heavy metal stress. The results of functional complementation tests in the yeast mutant suggested that NtCSD1a, NtFSD1e and NtMSD1b scavenge ROS produced by heavy metal stress. This study represents the first genome-wide analysis of the NtSOD gene family, which lays a foundation for a better understanding of the function of the NtSOD gene family and improving the tolerance of plants to heavy metal toxicity.

Silica (SiO2) powder and physical deposition technique were performed to fabricate superhydrophobic silicone rubber (SR) surfaces, and the contact angle and the rolling angle were 160.3 ± 1.0° and 2.8 ± 0.3°, respectively (the contact angle and the rolling angle of the original surface of the SR were 130 ± 1.8° and 36.7 ± 0.8°, respectively). The surface roughness of the sample was measured by interferometric three-dimensional topography profiler, and the results showed that the surface roughness increased after being treated by SiO2. A self-cleaning test was designed to verify the self-cleaning effect of the sample surface. Besides, a scanning electron microscope (SEM) was employed to observe the microstructure of the sample surface and the dispersion of SiO2, and energy dispersive spectroscopy (EDS) was utilized to determine the element composition and content of the sample surface. In order to further demonstrate the superhydrophobic property of the surface of the sample, the horizontal bouncing test at room temperature (25 °C) and the tilted bouncing test at an angle of 10° with the horizontal plane were carried out, and it was found that the sample had remarkable bouncing performance. Moreover, high temperature bounce tests were performed to investigate the stability of the surface superhydrophobic property of the sample, indicating that the sample had significant high temperature resistance.

Supplemental material, sj-pptx-2-tag-10.1177_17562848221124029 for ‘FLARE’ of tumor marker in advanced gastric cancer treated with first-line systemic therapy by Fangyuan Zhang, Menglan Zhai, Jinru Yang, Lei Zhao, Zhenyu Lin, Jing Wang, Tao Zhang and Dandan Yu in Therapeutic Advances in Gastroenterology

Supplemental material, sj-docx-3-tag-10.1177_17562848221124029 for ‘FLARE’ of tumor marker in advanced gastric cancer treated with first-line systemic therapy by Fangyuan Zhang, Menglan Zhai, Jinru Yang, Lei Zhao, Zhenyu Lin, Jing Wang, Tao Zhang and Dandan Yu in Therapeutic Advances in Gastroenterology

Supplemental material, sj-pptx-1-tag-10.1177_17562848221124029 for ‘FLARE’ of tumor marker in advanced gastric cancer treated with first-line systemic therapy by Fangyuan Zhang, Menglan Zhai, Jinru Yang, Lei Zhao, Zhenyu Lin, Jing Wang, Tao Zhang and Dandan Yu in Therapeutic Advances in Gastroenterology

The white layer and residual stress formed in a hard cutting process significantly influence the wear resistance of the workpiece. Orthogonal hard cutting experiments were performed on AISI 52100 steel with PCBN inserts. The results reveal that the white layer is formed on machined surfaces. Moreover, residual compressive stress exists in the white layers when the workpieces are cut by unworn tools, whereas tensile stress exists in the white layers when the workpieces are cut by worn tools. Under lubricated condition, the white layer (with the characteristics of high hardness and grain refinement) improves the resistance to abrasive wear. The high retained austenite content improves the resistance to fatigue wear. Furthermore, the residual compressive stress in the white layer inhibits the initiation and propagation of cracks, thereby increasing the fatigue wear resistance. Meanwhile, the residual tensile stress increases the speed of crack propagation in the white layer, which decreases the fatigue wear resistance. Under dry condition, the high hardness and grain refinement of the white layer increase the strength of the machined surface, thereby improving the adhesive wear resistance. The residual stress does not affect the wear resistance.

Martensite volume fraction determines the hardness and wear resistance of workpiece, predicting the martensite volume fraction of the white layer is of great significance for improving the surface quality of the workpiece. Accordingly, a theoretical model on the martensite volume fraction was developed in combination with the martensite transformation temperature model and the hard-cutting FE model. A finite element (FE) model of the hard-cutting was established to obtain the stress distribution of the workpieces. A calculation model of martensite phase transformation temperature $$M_{\text{S}}$$ under the influence of the cooling rate and stress was deduced based on the change of Gibbs free energy. A theoretical model of martensite volume fraction $$f_{\text{M}}$$ of the white layer was developed based on the $$M_{\text{S}}$$ and the FE simulations. The $$f_{\text{M}}$$ calculated by the theoretical model is in accordance with the experimental result. The effects of cutting speed, feed rate, flank wear and tool rake angle on the $$f_{\text{M}}$$ in the white layers were predicted and analyzed; the results show that the $$f_{\text{M}}$$ decreases first and then increases with the cutting speed, decreases with the feed rate and the flank wear, and increases with the tool rake angle.

BackgroundIt was widely accepted that programmed death-ligand 1 (PD-L1) positive, tumor mutational burden-high (TMB-H) or microsatellite instability-high (MSI-H) tumor are prone to have better treatment response to immune checkpoint blockade. The value of immune checkpoint blockade in PD-L1 negative gastric cancer patients has been questioned due to lower objective response rate (ORR).Case PresentationWe report an unusual case of a PD-L1 negative, proficient mismatch repair (pMMR)/microsatellite stability (MSS), tumor mutational burden-low (TMB-L) gastric cancer patient who achieved good response to immune checkpoint blockade after failure of systematic treatment. Multiple lymph nodes and bone metastases are the main characteristics of this patient. The patient survived for more than 30 months after diagnosis.ConclusionsThis case suggested that PD-L1 negative gastric cancer patient may also benefit from immune checkpoint blockade. In gastric cancer, patients with lymph node metastasis may be potential beneficiaries.

The white layer formed during the hard-cutting process impacts the surface quality and mechanical properties of a workpiece significantly. Obtaining the accurate critical cutting speed for white layer formation is beneficial to the quality control and parameter selection of cutting. Accordingly, combining with the finite element (FE) method, a critical cutting speed model of white layer formation was developed based on the solid phase transformation free energy theory, in which the thermal–mechanical effects were considered. To calculate the free energy change during the hard-cutting process, an austenite transformation driving force model was established. This model indicated that the cutting temperature, stress, and strain can provide the required driving force for austenite transformation in the white layer formation process. An FE model of the hard-cutting process was created to obtain the thermal and mechanical parameters. The critical cutting speed of white layer formation of AISI 52100 hardened steel was predicted in this study. The predicted result was in accordance with the experimental result. Moreover, the relationship between the critical cutting speed and cutting parameters were analyzed explicitly. We found that the critical cutting speed of white layer formation increased with the tool rake angle and decreased with the increase in cutting thickness and flank wear.

Levofloxacin (LEV) infiltrated in groundwater has threatened the safety of drinking water. For in-situ remediation of LEV-contaminated groundwater, there exists a main challenge of exploiting proper high efficient backfill medium in utilizing charming permeable reactive barriers (PRBs). Herein, three porous shapeable three-component hydrogen-bonded covalent organic aerogels (HCOA-1, HCOA-2 and HCOA-3) were fabricated based on a multiple-linking-site strategy to evaluate for adsorptive removal of LEV. The three HCOAs exhibited satisfactory performance in LEV adsorption that could integrate high adsorption capacity, good antiion interference, excellent recyclability and wide pH tolerance. The different regularity of kinetics and isotherms of three HCOAs signified that electrostatic effect, pore preservation, hydrogen bonding probably govern the adsorption process in combination, coupling with π-π electron-donor-acceptor (EDA), dipole-dipole and hydrophobic-hydrophobic interaction besides. In addition, the response surface methodology (RSM) was employed for studying the single and synergetic effects of selected variables and optimizing operation conditions. Furthermore, a laboratory PRB column packed with processable HCOA-2 was set up to investigate the LEV removal, and the breakthrough data was explained by Adams-Bohart, Thomas, BDST and Yoon-Nelson models. We believe could hopefully bring HCOAs into the real in-situ remediation of such challenging and persistent LEV-polluted groundwater with further massive-scale efficiently.

The microstructure and residual stresses of white and dark layers formed during a hard-cutting process have significant influence on the surface integrity of a workpiece. Therefore, the microstructure and residual stress of white and dark layers at low and high cutting speeds, along with different levels of flank wear are discussed, based on the experiment and simulation results. The orthogonal hard-cutting experiments on AISI 52100 steel were performed using polycrystalline cubic boron nitride (PCBN) inserts. A finite element model was developed to simulate the hard-cutting process. The microstructure and residual stress of the white and dark layers were analyzed through scanning electron microscopy, transmission electron microscopy, and an X-ray diffraction stress analyzer. The results indicate that the thickness of the white and dark layers is determined by the cutting heat and plastic strain in the subsurface. The grain size of the white and dark layers increases with cutting speed and flank wear. The formation mechanism of the dark layer changes from dynamic recovery to dynamic recrystallization with increase in flank wear. The residual compressive stress in the white layer at low cutting speeds is mainly caused by the microstructure of the white layer and plastic deformation, and the residual tensile stress in the white layer at high cutting speeds is mainly caused by the cutting heat. Tensile stress is induced in the white and dark layers when the workpiece is cut by a worn tool, and the tensile stress is caused by the high cutting heat and microstructure of the dark layer.

Herein, we fabricated an ultra-light graphene aerogel/Bi2WO6 (GA/BW) photocatalyst with macroscopic 3D architecture via in-situ synthesis, which had preferable activity for organic wastewater purification. We carefully characterized the physical and chemical properties of this macroscopic 3D architecture, finding that the flower-like Bi2WO6 (BW) uniformly loaded on the surface of GA, improving the visible light absorption performance, photon-generated carrier separation efficiency and organic contaminants adsorption ability, as well as photocatalytic ability compared with that of pure BW powders. When the mass ratio of GA and BW is 6:8, the degradation efficiency of rhodamine B (RhB) and sulfanilamide (SN) can reach 97.49% and 55.81% in 120 min, respectively. The as-prepared GA/BW composite is ultra-light and suitable for practical wastewater purification due to its flexibility and recyclability. The trapping experiments involved the main active species in the photocatalytic process were carried out and the results indicated that the h+ is the dominant oxidative species for the degradation of RhB.

White layer formed in hard cutting process has great influence on surface quality of the workpiece, simulation of the white layer has great significance. Dynamic recrystallization critical temperature model is derived to calculate the critical temperature of the dynamic recrystallization in the white layer. A finite element model was developed to simulate the hard cutting process based on the Johnson-Cook constitutive equation. The dynamic recrystallization critical temperature was derived based on the true stress-strain curves obtained by the split Hopkinson pressure bar experiments. The cellular automaton model which aims to simulate the white layer grains formed by the dynamic recrystallization process in hard cutting is established. The temperature and strain data extracted from the finite element model are used in the cellular automaton model. The contrast between the simulation and experimental results demonstrates that the cellular automaton model can simulate the dynamic recrystallization process in the white layer accurately. The dynamic recrystallization processes in the white layer under different cutting speed and flank wear are simulated based on the finite element - cellular automaton model. The results show that the dynamic recrystallization grain size of the white layer decreases with the increase in cutting speed and tool wear.

Emerging applications for environmental purification require agents that not only possess high decontamination efficiency, but also are capable of withstanding mechanical deformation without secondary pollution and degradation of performance. To this end, we have controlled synthesis of mechanically flexible graphene aerogel (GA) by vacuum freeze-drying of their hydrogel precursors obtained from heating the aqueous mixtures of graphene oxide (GO) and Vitamin C (VC) without stirring. Through the adaptable process conditions, such as the particle size of carbon, GO concentration, dosage of reducing agent and solution pH, the highly porous, ultralight and mechanically flexible GA are synthesized. Owing to the porous, robust and stable structure, the resulting GA show very promising performance in water purification including enrichment of organic liquid solvents (alcohols, oil and alkanes), removal of hexavalent chromium Cr(VI) and purified industrial wastewater, as well as flexible conductors. The successful creation of the GA may provide new insights into the design of carbon-based aerogels for various applications, as the GA can be prepared via a very simple procedure and available in macroscopic diverse morphologies with tunable porosity.

Al/SiCp composite machining is considerably difficult owing to the presence of hard particles that result in complex friction at the tool-chip interface. To provide a more comprehensive understanding of the friction at the tool-chip interface in the machining of Al/SiCp composites, this study developed a three-phase friction model that considered the influence of matrix adhesion, two-body abrasion and three-body rolling. Then, to improve the accuracy of the simulation in Al/SiCp composite machining, a finite element (FE) model of randomly distributed round particles was developed by incorporating the three-phase friction model. The simulated chip formation and the cutting force based on the proposed FE model were compared to the experimental results and used to verify the three-phase friction model. The results indicated that two-body sliding, three-body rolling, and matrix sticking are three forms of contact that determined the tool-chip interface friction. The simulated values of the cutting force based on the proposed friction model follow a similar trend and were in good agreement with the experimental magnitudes. In addition, chip formation simulations at different stages in Al/SiCp composites machining were studied, and the chip morphology of the cutting simulation was consistent with the experiments that could be categorized as a saw-toothed chip.

White and dark layers formed in hard cutting a workpiece have a great influence on the distribution of residual stress and performance of the workpiece. Orthogonal cutting of AISI 52100 steel with PCBN inserts was employed, and the microstructure, phase components, carbon distribution, and hardness of the white and dark layers were analyzed via scanning electron microscopy, X-ray diffraction, electron probe microanalysis, nanoindentation, and transmission electron microscopy. The results demonstrate that the white layer is formed by a rapid austenite transformation and quenching process, and the dark layer is formed by a tempering process. Plastic deformation promotes the austenite transformation of the white layer and the tempering process of the dark layer and plays a role in the grain refinement of both the white and dark layers. The rapid heating process produced by the cutting process causes the austenite transformation and increases the nucleation rate of austenite. The plastic deformation provides the phase transformation driving force, which can accelerate the formation of the white layer. Meanwhile, defects such as dislocations formed owing to plastic deformation refine the subgrains in the white layer. The heat that transfers into the subsurface and the stress induced by the plastic deformation provide the driving force for dynamic recovery and dynamic recrystallization in the dark layer; the subgrains in the dark layer are segmented by dislocation motion.

The ZnSn(OH)6 nanocubes were prepared under different pH (3–12.4) by liquid precipitation, well characterized and further used for wastewater treatment. The results indicated that the ZnSn(OH)6 nanocubes prepared at pH = 11.1 possessed of uniform size distribution and excellent photocatalytic activity, the degradation efficiency to MB reaches 76.3% after 5 h natural sunlight irradiation. Subsequently, the prepared ZnSn(OH)6 nanocubes was further thermal treated (200 °C, 24 h) in four different solvents, containing deionized water, stock solution, mixed solution (Vwater: Vethanol: Vglacial acetic acid = 3:1:1) and ethanol, named as H-1, H-2, H-3 and H-4, respectively. H-2 and H-3 showed superior photocatalytic performance and the removal efficiency of MB improved to be almost 100%, as well as red-shifted light absorption edge and the band gap energies reduced 0.9 and 0.93 eV, respectively. Moreover, free radical capture experiments showed that the h+ and ·O2− are the main active species for the ZnSn(OH)6 nanocubes and H-2, respectively, while all these three ·OH, ·O2− and 1O2 radicals for H-3. Those results suggested that both pH regulation and thermal treatment could efficiently improve the microscopic morphology, crystal structure and photocatalytic activity of the ZnSn(OH)6, which might pave the way for the artful design of other high-performance catalysts.

Tactile displays1 have been widely used in information transfer through various tactile patterns on mobile devices. The fundamental consideration in designing tactile interactions is intuitive tactile feedback patterns that convey information. This study investigates the user perception of various tactile stimuli patterns over frictional surface on mobile phones in terms of strong feedback. We designed 36 different tactile patterns with a combination of different signal lengths (w1 = 0.2-3.2 mm) and intervals (w2 = 0.2-3.2 mm) of frictional feedbacks. These parameters covered most cases in the tactile pattern design for a mobile phone. Using these stimuli, we presented 666 pairs of comparisons to 50 participants who would distinguish whether the stimuli in each pair were similar or different. The results indicated the dense patterns in which smaller values of w1 and w2 conveyed stronger tactile feedback and quick distinguish time to users. Meanwhile, the denser tactile patterns had significant differences, which suggests that users can easily distinguish different strong tactile patterns even when these patterns appeared simultaneously. The results of this study can be used as a reference to design tactons, obtain non-visual information, or encode tactile language.

In the rotary compressor, the rolling piston and the contacted rotor-journal bearing system are basically moving components. Because of the inertia forces and the periodically changing gas force acting on the rolling piston and the rotor, the journal bearing suffers very large loads. It always leads to serious vibration of the rotor-journal bearing system, and the wear of the rotor. Thus, the vibration must be reduced. In this paper, research works of vibration characteristics of the rotor-journal bearing system were carried out to provide evident of optimizing its structure to reduce the vibration. The average values of the natural frequencies and the vibration mode of the rotor-journal bearing system was obtained based on three-dimensional numerical simulations with finite element method using APDL routine. The power spectral density map of the exciting forces on rolling piston was obtained by the Fourier transformation. It could be used to judge whether resonance vibration would happen during working process of the compressor. The analysis results showed that the lateral vibration mode and the torsion vibration mode were the main vibration modes of the rotor-journal bearing system, and the first four orders of the exciting frequencies played a major role on the vibration of the system.

About 0.05 mg Cd l-1 was found in the irrigation water contaminated by the wastewater discharged from tungsten ore dressing plants, and about 1 mg Cd kg-1 was found in irrigated acid soils. The main sources of cadmium intake by residents of the polluted areas are agricultural products. The average intake of cadmium was 367-382 micrograms day-1, and for smokers 417 micrograms day-1. Among the residents who have been exposed to cadmium for more than 25 years, cadmium absorption (urinary cadmium greater than or equal to 10 micrograms g-1 creatine) was 60% and an early effect on the target organ (urinary cadmium greater than or equal to 15 micrograms g-1 creatinine and urinary beta 2-microglobulin greater than 500 micrograms g-1 creatinine) was detected in 17% of the sample of 433 persons. Levels of urinary cadmium and blood cadmium exceeded the critical value in the exposed group. The concentrations of urinary calcium, beta 2-microglobulin and N-acetyl-beta-D-glucosaminidase were significantly higher in residents of contaminated areas than in those of control areas. Case-control study of the residents shows that many have suffered from a nephropathy with tubulo-interstitial abnormalities. Owing to the combined cadmium effect, the cases with fractional beta 2-microglobulin excretion greater than 0.10 were 46% in the exposed population, and were much higher than that in the control group (20.3%).