High-pressure torsion (HPT) was applied for the Ni49.6Ti35.4Hf15 (at.%) alloy up to 1/4, 2 and 16 turns under a pressure of 4.0 GPa. The samples were examined using X-ray diffraction (XRD), ...transmission electron microscope (TEM) and microhardness measurements. The results indicate that the mixture of an amorphous and nanocrystalline microstructure developed in the investigated NiTiHf alloy as the number of HPT turns was increased to two. The average hardness of the samples increased from 330 Hv to 500 Hv after 16 turns of HPT. Very fine martensite developed when the HPT-processed samples were annealed at 550 °C and the finer microstructures were attained with higher HPT turns. Differential scanning calorimetry (DSC) tests were performed in the post-HPT annealing samples to clarify the transformation behavior after severe plastic deformation in HPT and subsequent annealing, so as to provide an experimental basis for the application of the shape memory alloy. The transformation temperature of the alloy decreased remarkably when the number of turns of HPT reached 16. It is suggested that the deformation extent and annealing temperatures should be considered in order to maintain a high transformation temperature while utilizing the strengthening effect of HPT in the NiTiHf alloy.
To maintain the straightness of an unmanned longwall mining face, a track geometry surveying model of the scraper conveyor was constructed based on the position of the shearer. A surveying instrument ...was developed employing an inertial measurement unit and axial encoder. Surveying tests were conducted using a longwall mining face mock-up, and the 3-D accuracy of the surveying instrument based on the mean radial spherical error and the spherical error probable (SEP) radius was determined to be 20.78 mm and 16.57 mm, respectively. The accuracy of the surveying system satisfied the requirements of a longwall mining face.
In the squinted synthetic aperture radar (SAR) imaging of the near-field environment, range-dependent characteristic of squint angle cannot be ignored, which causes azimuth-dependent range cell ...migration (RCM) after linear range walk correction (LRWC). In this study, an efficient SAR imaging algorithm applied in the near-field environment is proposed. In the processing of the range focusing, LRWC is firstly used to remove the linear RCM. Then, the residual LRCM is expanded into azimuth-invariant and azimuth-variant terms in consideration of the residual LRCM of azimuth-dependent. Range cell migration azimuth scaling (RCMAS) is designed to remove the azimuth-variant term before secondary range compression (SRC) and range compression (RC). In the azimuth focusing, azimuth distortion compensation (ADC) is performed to compensate the azimuth distortion, following which azimuth nonlinear chirp scaling (ANCS) is applied to equalize the frequency modulation (FM) rate for azimuth compression (AC). The simulated results show that more accurate and improved imaging result can be obtained with the proposed algorithm.
High-pressure torsion (HPT) was applied to the Ni50.6Ti49.4 (at. %) alloy ingot up to 1/4, 2, 16, 32 and 48 turns under a pressure of 6.0 GPa. The samples were examined by X-ray diffraction (XRD), ...transmission electron microscope (TEM) and microhardness measurement. The results indicate that martensitic transformation and formation of amorphous phase occurred during the HPT process. As the HPT turns increased, more amorphous phase formed. The fraction of amorphization was analyzed based on the X-ray results. The microhardness increased with the HPT turns, which may be related to strain-induced martensite transformation, formation of the amorphous phase, increased dislocation densities and grain refinement. Differential scanning calorimetry (DSC) test revealed that shape memory alloys can be produced by HPT and post-HPT annealing from a NiTi ingot.
Endogenous retroviruses (ERVs) originate from ancestral germline infections caused by exogenous retroviruses. Throughout evolution, they have become fixed within the genome of the animals into which ...they were integrated. As ERV elements coevolve with the host, they are normally epigenetically silenced and can become upregulated in a series of physiological and pathological processes. Generally, a detailed ERV profile in the host genome is critical for understanding the evolutionary history and functional performance of the host genome. We previously characterized and cataloged all the ERV-K subtype HML-8 loci in the human genome; however, this has not been done for the chimpanzee, the nearest living relative of humans. In this study, we aimed to catalog and characterize the integration of HML-8 in the chimpanzee genome and compare it with the integration of HML-8 in the human genome. We analyzed the integration of HML-8 and found that HML-8 pervasively invaded the chimpanzee genome. A total of 76 proviral elements were characterized on 23/24 chromosomes, including detailed elements distribution, structure, phylogeny, integration time, and their potential to regulate adjacent genes. The incomplete structure of HML-8 proviral LTRs will undoubtedly affect their activity. Moreover, the results indicated that HML-8 integration occurred before the divergence between humans and chimpanzees. Furthermore, chimpanzees include more HML-8 proviral elements (76 vs. 40) and fewer solo long terminal repeats (LTR) (0 vs. 5) than humans. These results suggested that chimpanzee genome activity is less than the human genome and that humans may have a better ability to shape and screen integrated proviral elements. Our work is informative in both an evolutionary and a functional context for ERVs.
Clusteroluminescence (CL) has recently gained significant attention due to its unique through-space interactions associated with a high dependence on the aggregation of subgroups. These distinct ...features could easily transform the stimuli into visual fluorescence and monitor the fluctuation of the environment but have not received sufficient attention before. In this work, supramolecular films are designed based on the neutralization reaction of anhydride groups and the self-assembly of dynamic covalent disulfide bonds in NaOH aqueous solution. The self-assembly of hydrophilic carboxylate chromophores and hydrophobic disulfide-containing five-membered rings could be observed by the variation of the aggregation state of carboxylate in CL. Furthermore, the dynamic cross-linking films obtained with water-sensitive carboxylate chromophores could alter the aggregation distance stimulated by surrounding water vapor, causing the emission wavelength to change from 534 to 508 nm by varying the relative humidity. This work not only provides an approach to monitor the self-assembly of clusteroluminogens but also offers new strategies for designing stimuli-responsive materials that utilize the intrinsic features of CL.
Because of the high organic carbon concentration in carbonaceous shale, a large proportion of carbonaceous shales are often misclassified into coals using visible and near-infrared (VIS-NIR) ...reflectance spectroscopy in the field of coal-gangue identification of hyperspectral remote sensing of coal mine. In order to study spectral characterization of coal and carbonaceous shale, three bituminite samples and three carbonaceous shales were collected from a coal mine of China, and their spectral reflectance curves were obtained by a field spectrometer in the wavelength range of 350–2500 nm. Only one carbonaceous shale could be easily identified from the three bituminite samples according to obvious absorption valleys near 1400 nm, 1900 nm, and 2200 nm of its reflectance curve while the other two carbonaceous shales have similar reflectance curves to the three bituminite samples. The effect of carbon concentration on reflectance curve was simulated by the mixed powder of ultralow ash bituminite and clay in 0.5 mm grain size under various mixing ratios. It was found that absorption valleys near 1400 nm, 1900 nm, and 2200 nm of the mixed powder become not obvious when the bituminite content is more than 30%. In order to establish an effective identification method of coal and carbonaceous shale, 250 other samples collected from the same coal mine were divided into 150 training samples and 100 prediction samples. Principal component analysis (PCA) and Gauss radial basis kernel principal component analysis (GRB-KPCA) were employed to extract principal components (PCs) of continuum removed (CR) spectra of the training samples in eight selected wavelength regions which are related to the main mineral and organic compositions. Two support vector machine- (SVM-) based models PCA-SVM and GRB-KPCA-SVM were established. The results showed that the GRB-KPCA-SVM model had better identification accuracies of 94% and 92% for powder and nature block prediction samples, respectively.
The efficacy and safety of immunotherapy have been widely recognized in gastrointestinal-related cancers. However, the efficacy of neoadjuvant camrelizumab for locally advanced esophageal squamous ...cell carcinoma (ESCC) has not been firmly established. This study compared the efficacy of camrelizumab in combination with neoadjuvant DCF (docetaxel, cisplatin and fluorouracil), with DCF alone for ESCC, and exploring biomarkers related to immune infiltration of the ESCC immunotherapy response.
We enrolled and randomly assigned patients with stage II-IVa ESCC to two study treatments: camrelizumab combined with docetaxel, cisplatin and fluorouracil (DCF) regimen and DCF regimen alone. The tissue for multiplex immunofluorescence (mIF) was obtained before and after neoadjuvant therapy. The Response Evaluation Criteria in Solid Tumors RECIST Version 1.1 (RECIST 1.1) and Tumor Regression Grade (TRG) was used to evaluate efficacy.
A total of 30 patients were enrolled in the study. Following neoadjuvant camrelizumab, the objective response rate (ORR) and the disease control rate (DCR) were 46.7% (7/15) and 95.7% (14/15), respectively. No patients reported complete remission, while ORR and DCR in the chemotherapy group were 26.7% (4/15) and 86.7% (13/15), respectively. R0 resection after neoadjuvant treatment was achieved in 3 out of 15 patients in the combined group and in all patients (15/15) in the chemotherapy group. In the combined group, M1-type tumor-associated macrophages and CD56dim NK cells were more abundant in responders than in non-responders (p < 0.05). A higher M1/M2 ratio was observed in responders (p < 0.05). With respect to the NGS, among the copy number amplified genes, the 11q13 amplicon (CCND1/FGF19/FGF4/FGF3) showed the highest frequency (47%, 7/15).
Neoadjuvant camrelizumab combined with chemotherapy improved ORR in locally advanced ESCC. M1-type tumor-associated macrophages and CD56dim NK cells might be utilized to predict camrelizumab efficacy.
► The extraction method of UHMWPE wear debris from artificial joint was researched. ► The average size of wear debris from tester is bigger than artificial joint's. ► The morphology of two kinds of ...wear debris are different. ► The thickness of the wear debris from implanted joint is smaller than from tester.
The artificial joint simulator is designed to simulate the complicated movement and environment of the artificial joint in vivo. Although the wear loss of materials evaluated on the artificial joint simulator under ISO standard is found to conform to that in vivo, there is a significant difference in the morphology of the wear debris obtained from the tester and human body. It is well known that the wear debris plays an important role in aseptic loosening of the artificial joint, and its morphology indicates the working conditions of the artificial joint. Therefore, it is necessary to distinguish the two kinds of wear debris. In this paper, the comparative study of ultra high molecular weight polyethylene (UHMWPE) wear debris from the implanted artificial joint and hip joint tester was performed on their size distribution, shape, 3-D feature, and thickness. Results show that the wear debris from joint simulator have different sizes and shapes such as strip, block, plate, and spherical etc., their average diameter is 7.54
μm, and its medium diameter is 6.89
μm. The most wear debris from artificial joint have the spherical or subsphaeroidal shapes, and a small amount of the debris have the unbroken plate structure, the average diameter is 1.33
μm, is about 18% of the wear debris’ from joint simulator, and the medium diameter of 2.95
μm, is about 43% of the wear debris’ from joint simulator. The results are expected to provide both experimental and theoretical foundation for improving the artificial joint simulator and optimizing the evaluation standards of the artificial joint materials.
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