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Abstract Objective We aim to explore the differences of the psychological distress of postoperative chemotherapy patients with colorectal cancer between mindfulness intervention combined with homogeneous medical concepts and mindfulness intervention only. Methods One hundred patients with colorectal cancer undergoing chemotherapy after surgery from Sep 2020 to Sep 2022 were enrolled and divided into active control group (Solution centered nursing interventions; homogenized medical and nursing professional teams; dedicated personnel responsible for “admission notices”; Regular follow-up after discharge) and mindfulness group (homogeneous medical concept + and concentrated solution + Mindfulness intervention) with 50 cases in each group according to different nursing methods. Results After nursing, the physical function, emotional function, cognitive function, and social function of the patients in the mindfulness group were significantly higher than those in the active control group. However, the overall life and economic difficulties of the patients in the mindfulness group were significantly lower than those in the active control group (P

In field hydraulic fracturing operation of shale gas development, the high pressure and large displacement liquid-particle two-phase fracturing fluid can be forced to change direction many times through high-pressure double-elbow, and be transported from the outlet pipeline of the fracturing pump to the main pipeline. The high-pressure double-elbow is prone to be affected by erosion wear and Fluid-Structure Interaction (FSI), resulting in perforation and fracture, posing a potential safety threat to field operation. In this study, we conducted the erosion wear experiments on 35CrMo steel used for high-pressure double-elbow in shale-gas fracturing. The erosion rates under different impact angles and flow velocities were obtained, and proposed a novel model of erosion prediction for high-pressure double-elbow. Then the numerical investigation was employed to conduct a comprehensive analysis of erosion wear, structural stress and deformation by the coupling of Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA). The effects of structural parameters such as connection straight pipe length, pipe inner diameter and fluid turning direction were discussed. The results indicate that with the increase of connection straight pipe length, the flow erosion decreases first then varies little, and the deformation gradually increases. Slight erosion wear but large structural stress and deformation in major inner diameter pipe. And the minimum degree of erosion and flow-induced deformation present with the fluid turning direction of double-elbow as 0°. The study can provide references for the design, installation and detection of high-pressure double-elbow and ensure safety in the process of shale gas fracturing.

Abstract Sliding-induced subsurface microstructure evolution is believed to be decisive for determining the friction and wear performance of metallic contacts as well as the development of tribo-magnetization. This expects to develop a new prediction method of wear state by elucidating the correlation between subsurface microstructure evolution and corresponding magnetic domain changes. Herein, subsurface microstructure evolution including crystal and magnetic domain under tribological action is investigated experimentally. Our results demonstrate that dislocation mediated plastic deformation decisively influences microstructural changes during tribological contact, further determining the magnetic domain structure. Specifically, sliding-induced plastic deformation causes an increase in the width of magnetic domains, but depth-dependent derived microstructure formed under severe plastic deformation such as the refined grains and sub-grains, in turn, promoted the refinement of magnetic domains and their discontinuity, forming depth-dependent magnetic domain structure. These results are helpful to clarify the evolution of tribo-magnetization and the pinning effect of dislocations on magnetic domains.

Objective: Exploring the different molecular and clinicopathological features of nodal cancer based on single cell sequencing can reveal the intertumoral heterogeneity in cancer, and provide new ideas for early diagnosis, treatment and prognosis analysis of cancer. Methods: The hotspots, the features of worldwide scientific output, and the frontiers concerning single cell sequence related to cancer from 2011 to 2024 were determined using our bibliometric analysis. Web of Science Core Collection (WOSCC) database was searched for publications on single cell sequence associated with cancer that were published between 2011 and 2024. According to the journals, keywords, number of records, affiliations, citations, and countries, we conducted a bibliometric analysis. With the use of the data gathered from the WOSCC, geographic distribution was visualized, keyword, affiliation, and author cluster analyses were conducted, and co-cited references were reviewed and a descriptive analysis was also performed. Results: From the analysis, it was concluded that 6189 articles that were published between 2011 and 2024 in total were identified. Frontiers in immunology is the leading journal with the most publications in field of the research. The five clusters that were identified for hotspots included immunotherapy, single-cell RNA sequencing, hepatocellular carcinoma, proliferation, gene expression appeared the most frequently. Journals, nations, organizations, scholars with most contribution and most referenced publications globally were extracted. Studies have mostly concentrated on the spatial transcriptomics, pan-cancer analysis, hepatocellular carcinoma et al. Conclusion: Single-cell sequencing plays a significant role in tumor diagnosis, treatment and prognosis.

The magnitude and distribution of contact stress on the metal-to-metal seal interface of premium connection has been confirmed as a direct factor of the sealing integrity. In this study, the method of evaluating sealability by measuring contact stress on metal-to-metal seals with the ultrasonic phased array is investigated. A loading system and ultrasonic phased array measurement system of cone-cone contact samples were created. The recommended detection method is focusing -deflection, and the time compensation method is suggested to extract the reflected wave peak of the sealing surface. The experiments show that the reflected wave peak declines with the rise of the axial load, with the big end showing the most noticeable reduction. The shift in the reflected wave peak also reflects the axial movement of the contact interface. The contact stress is calculated according to the reflection coefficient and compared with the simulation results. The distribution trend of contact stress is consistent. The sealing index measurement error is less than 15%, and the measurement error is decreased with the decrease of the sealing surface angle. Then, the nephogram of contact stress distribution on the sealing surface is formed to visualize the contact stress, which takes on great significance in engineering.

Hydrate formed in the wellbore during deepwater shallow drilling will affect the operation safety, so it is necessary to predict and analyze the hydrate formation range and degree in the wellbore annulus. One development well in Lingshui Gas Field in South China Sea was taken as the research object, and the numerical simulation method for hydrate formation in deepwater drilling was built based on CSMHyK hydrate dynamics model and OLGA multiphase flow equation. The temperature-pressure field of the wellbore under various working conditions was calculated, the subcooling density was introduced to present the possibility of hydrate formation, the range and degree of hydrate formation in the wellbore annulus were predicted, and the parameter sensitivity of drilling fluid displacement, inlet temperature, density and shallow gas storage pressure was analyzed. The results show that under the assumed working conditions, the riser annulus near the mudline has the risk of hydrate formation, with the largest amount of hydrate formation in the annulus with a water depth of 800-1 000 m. The smaller the displacement of drilling fluid is, the lower the inlet temperature is, the greater the risk of hydrate formation will be, and the amount of hydrate formed in hazardous pipe section may exceed 40 kg/m3. The subcooling density, length of interval where hydrate is formed, total amount of hydrate formed and peak rate were selected as the characteristic values for assessing hydrate formation, and the quantitative analysis method for wellbore hydrate risk level was built. The research results are expected to provide theoretical guidance for hydrate control and optimization design of drilling schemes during deep water shallow drilling.

In terms of the structural health inspection of storage tanks by ultrasonic guided wave technology, many scholars are currently focusing on the tanks’ floor and walls, while little research has been conducted on storage tank roofs. However, the roof of a storage tank is prone to corrosion because of its complex structure and unique working environment. For this purpose, this paper proposes a reflection/transmission signal amplitude ratio (RTAR) coefficient method for corrosion depth assessment. We studied the relationship between the RTAR coefficient, the corrosion depth, and the guided wave frequency to establish a depth assessment model. More importantly, unlike the traditional reflection coefficient method, the characteristics of guided wave signals, including the propagation and attenuation, are introduced in this model for accurate assessment. To eliminate the interference of residual vibration and improve the detection accuracy of defects, we built a corrosion detection system by using piezoelectric sensors and carried out field tests to verify the performance of the proposed method. We demonstrate that corrosion defects with a minimum depth of 0.2 mm can be quantitatively evaluated.

In order to investigate the relationship between tribo-magnetization and wear phenomena, a series of sliding-friction tests were carried out using a pin-on-block reciprocator type device, which was specially designed to generate sliding friction and to detect magnetic fields. The tribological behavior was observed by a charge-coupled device (CCD) camera in real time, and the magnetic signal was detected by using a two-axis magnetic sensor. It was found that as the friction continues, both the tangential and the normal components of magnetic field on the material surface increase gradually, and that both the average value of the tangential magnetic field ΔH(x)mean and the peak-to-peak value of the normal magnetic field Vpp at the wear scar clearly reflect changes of the wear state. Furthermore, in order to better understand the tribo-magnetization phenomenon, the changes of surface morphology and wear debris in different wear stages were analyzed. Moreover, an improved magnetic dipole model that considered the distribution of magnetic charges on the worn surface was established. This model can successfully describe the tribo-magnetization phenomenon during the stable wear stage, and should be useful for characterizing frictional wear phenomena in the future.

To monitor fatigue crack initiation and propagation, and to judge the fatigue damage status of ferromagnetic material, fatigue bending tests of four-point single edge notch bend (SENB4) specimens were carried out. Metal magnetic memory signals were measured during the whole fatigue process. The results showed that the fatigue process could be divided into four stages by observing the morphology of the fracture surface. With the increase of fatigue loading cycles, the tangential component of the magnetic field (Hx) and the normal component of the magnetic field (Hy) increased. At the notch Hx presented a “trough” shape and had a maximum value at the midpoint, while Hy at the notch rotated clockwise around the midpoint. Compared with the tangential characteristic parameters, the variation of normal characteristic parameters (i.e., maximum gradient value of Hy (Ky-max) and the variation range of Hy at the notch (∆Hyn), with the fatigue loading cycles are more similar to the variation of fatigue crack length with loading cycles), both Ky-max and ∆Hyn had a good linear relationship with fatigue crack length. Plastic deformation accumulated on both sides of the fatigue crack, and metal magnetic memory (MMM) signals measured from the specimens were able to indicate the location of the fatigue crack and the variation of the fatigue crack length. Furthermore, the distribution of magnetic signals was analyzed according to the theories of stress magnetization and magnetic flux leakage.

Rapeseed (Brassica napus) is an important oil seed crop, providing more than 13% of the world’s supply of edible oils. An in-depth knowledge of the gene network involved in biosynthesis and accumulation of seed oil is critical for the improvement of B. napus. Using available genomic and transcriptomic resources, we identified 1,750 acyl lipid metabolism (ALM) genes that are distributed over 19 chromosomes in the B. napus genome. B. rapa and B. oleracea, two diploid progenitors of B. napus, contributed almost equally to the ALM genes. Genome collinearity analysis demonstrated that the majority of the ALM genes have arisen due to genome duplication or segmental duplication events. In addition, we profiled the expression patterns of the ALM genes in four different developmental stages. Furthermore, we developed two B. napus near isogenic lines (NILs). The high oil NIL, YC13-559, accumulates more than 10% of seed oil compared to the other, YC13-554. Comparative gene expression analysis revealed upregulation of lipid biosynthesis-related regulatory genes in YC13-559, including SHOOTMERISTEMLESS, LEAFY COTYLEDON 1 (LEC1), LEC2, FUSCA3, ABSCISIC ACID INSENSITIVE 3 (ABI3), ABI4, ABI5, and WRINKLED1, as well as structural genes, such as ACETYL-CoA CARBOXYLASE, ACYL-CoA DIACYLGLYCEROL ACYLTRANSFERASE, and LONG-CHAIN ACYL-CoA SYNTHETASES. We observed that several genes related to the phytohormones, gibberellins, jasmonate, and indole acetic acid, were differentially expressed in the NILs. Our findings provide a broad account of the numbers, distribution, and expression profiles of acyl lipid metabolism genes, as well as gene networks that potentially control oil accumulation in B. napus seeds. The upregulation of key regulatory and structural genes related to lipid biosynthesis likely plays a major role for the increased seed oil in YC13-559.

This paper presents a novel acoustic wave-based method for the detection of leakage in downhole tubing of offshore gas wells. The localization model is developed on the basis of analyzing the propagation model of leakage acoustic waves and the critical factors in localization. The proposed method is validated using experimental laboratory investigations that are conducted to locate tubing leakage by setting five holes at different positions on the tubing wall. A detection system is developed for the leakage acoustic waves in the tubing-casing annulus, where one acoustic sensor is installed at the annulus top. Laboratory experimental results show that the depth of downhole leakage can be effectively located by using the proposed localization model. The localization errors are kept at a very low level, and are mainly generated from extracting the characteristic time and calculating annular acoustic velocity. A case study focusing on an offshore gas well is presented to illustrate the feasibility of the proposed method, and to demonstrate that the proposed model can locate the liquid level and leakage points under field conditions. The test can be performed without interrupting the production of gas wells.

The fatigue fracture of a drillstring could cause drilling disturbances and some negative impacts (e.g., economic loss) will be brought when restoring the drillstring to functionality. In order to evaluate the effects of the fatigue damage of the drillstring during drilling, a new apparatus, which could monitor the load level in real-time, was built to perform the four-point bending fatigue test on 35CrMo steel, a typical material of drillstrings. Such an apparatus is based on metal magnetic memory (MMM) technology and can acquire the tangential and normal components of MMM signals. Based on the analysis of the change of surface morphology and MMM signals, it was concluded that the variation of MMM signals could be divided into four stages, which are used to accurately describe the fatigue damage process of the drillstring. Additionally, the MMM signal characteristics are introduced to especially evaluate the fatigue damage of the drillstring, including crack initiation. Furthermore, the scanning electron microscopy (SEM) results demonstrated that morphologies of fatigue fracture were related to the variation of MMM signals. Linear fitting results indicated that fatigue crack length had a good linear relationship with the characteristics, so it is feasible to monitor fatigue damage and predict the residual life of a drillstring by using MMM technology.

In coal seam gas (CSG) wells, water is periodically removed from the wellbore in order to keep the bottom-hole flowing pressure at low levels, facilitating the desorption of methane gas from the coal bed. In order to calculate gas flow rate and further optimize well performance, it is necessary to accurately monitor the liquid level in real-time. This paper presents a novel method based on autocorrelation function (ACF) analysis for determining the liquid level in CSG wells under intense noise conditions. The method involves the calculation of the acoustic travel time in the annulus and processing the autocorrelation signal in order to extract the weak echo under high background noise. In contrast to previous works, the non-linear dependence of the acoustic velocity on temperature and pressure is taken into account. To locate the liquid level of a coal seam gas well the travel time is computed iteratively with the non-linear velocity model. Afterwards, the proposed method is validated using experimental laboratory investigations that have been developed for liquid level detection under two scenarios, representing the combination of low pressure, weak signal, and intense noise generated by gas flowing and leakage. By adopting an evaluation indicator called Crest Factor, the results have shown the superiority of the ACF-based method compared to Fourier filtering (FFT). In the two scenarios, the maximal measurement error from the proposed method was 0.34% and 0.50%, respectively. The latent periodic characteristic of the reflected signal can be extracted by the ACF-based method even when the noise is larger than 1.42 Pa, which is impossible for FFT-based de-noising. A case study focused on a specific CSG well is presented to illustrate the feasibility of the proposed approach, and also to demonstrate that signal processing with autocorrelation analysis can improve the sensitivity of the detection system.