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Sinusoidal buckling of drill strings will be easily caused during drilling process of extended-reach horizontal wells due to the factors such as excessive well length and larger friction torque, which will cause measurement errors of well depth and vertical depth and furthermore influence the accurate calculation of ECD. We have corrected the traditional ECD calculation model, considered the measurement errors of well depth and vertical depth caused by the sinusoidal buckling of drill strings, and established a set of equivalent circulating density (ECD) calculation model suitable for extended-reach horizontal wells to meet the requirements for fine ECD control during the drilling operation. We have combined the data from an extended-reach horizontal well in the East China Sea and compared the ECD data obtained from the recorded stand pipe pressure with the prediction results from Landmark commercial software、the model in this work and the conventional model. Results show that the prediction results by the model in this work are closest to the recorded values when drill string sinusoidal buckling occurs. Besides, the ECD value predicted by the model considering the measurement errors of well depth and vertical depth caused by the sinusoidal buckling of drill strings is smaller due to the factor that the length of drill strings with sinusoidal buckling is larger than the actual well depth. With the identical case well data, the larger the sinusoidal buckling degree of downhole drill strings, the smaller the predicted ECD value. The model can reduce risks for drilling operations of extended-reach horizontal wells and provide more accurate reference data for their well control operations.

This study investigates wellbore stability in ultra-deep extended-reach wells (ERWs) in the East China Sea, where perforated pipes (a type of screen completion) are commonly used to support wellbore walls and prevent collapse. Cost constraints sometimes lead to the omission of this support, yet significant wellbore collapse is rarely observed. The instability is primarily attributed to variations in production pressure differences. A predictive model for critical pressure difference was developed based on immersion experiments and single-triaxial rock mechanics tests. The results from immersion tests revealed that, in water-bearing strata, the critical pressure difference decreased significantly, drop-ping by 20.07% after two days of rock core immersion and by 28.35% after seven days. Key factors influencing this difference, such as well inclination, rock cohesion, internal friction angle, Poisson’s ratio, and Biot coefficient, were identified. As production continues, pore pressure depletion reduces this difference, particularly when pore pressure falls below 23.5 MPa, leading to wellbore instability. On-site validation in three ultra-deep ERWs showed that the model’s predictions aligned well with actual conditions, with a confidence interval analysis further validating the model’s accuracy. The proposed model provides valuable guidance for future ultra-deep well development in the East China Sea.

In order to solve the contradiction between the safety requirements of well control in the upper reservoir and the loss of kill fluid in the lower reservoir, the idea of “compound plugging technology” was proposed to solve the abnormal pressure inversion phenomenon of “the co-existence of blowout and lost circulation” with large interlayer pressure difference. Flexible colloidal particle-fiber composite temporary plugging fluid was developed. The plugging layer formed by the temporary plugging fluid of flexible rubber fiber can withstand the positive pressure difference of more than 40 MPa, and there is no overflow and leakage. The advantages of compound temporary plugging fluid under large differential pressure are verified and it has a good application prospect.

For a cruise ship in heavy sea conditions, self-propulsion performance prediction is important for ensuring its safety. In this study, a numerical simulation approach that models the free running of a ship is presented, and a full-scale small cruise ship is verified using a ship model experiment. Based on this method, a free-running cruise ship encountering six kinds of wave conditions was simulated, and the characteristics of the ship’s motion, added resistance, and propeller loading were analyzed. The results demonstrated that the free-running approach can simulate the self-propelled motion of a full-scale ship, and that it converges more quickly than the traditional self-propulsion simulation method. The ship’s speed, heave, pitch, and thrust fluctuated when it moved through the waves, and λ/Lwl had a greater influence on the amplitude of these fluctuations than did H/Lwl. Furthermore, the propeller loading exhibited a sharp increase, and the maximum loading coefficient exceeded 500%, which may pose a safety risk.

Lead sulfide (PbS) colloidal quantum dot (CQD) photodiodes integrated with silicon‐based readout integrated circuits (ROICs) offer a promising solution for the next‐generation short‐wave infrared (SWIR) imaging technology. Despite their potential, large‐size CQD photodiodes pose a challenge due to high dark currents resulting from surface states on non‐passivated (100) facets and trap states generated by CQD fusion. In this work, we present a novel approach to address this issue by introducing double‐ended ligands that supplementally passivate (100) facets of halide‐capped large‐size CQDs, leading to suppressed bandtail states and reduced defect concentration. Our results demonstrate that the dark current density is highly suppressed by about an order of magnitude to 9.6 nA cm−2 at −10 mV, which is among the lowest reported for PbS CQD photodiodes. Furthermore, the performance of the photodiodes is exemplary, yielding an external quantum efficiency of 50.8% (which corresponds to a responsivity of 0.532 A W−1) and a specific detectivity of 2.5 × 1012 Jones at 1300 nm. By integrating CQD photodiodes with CMOS ROICs, the CQD imager provides high‐resolution (640 × 512) SWIR imaging for infrared penetration and material discrimination. This work explores the potential of PbS colloidal quantum dots (CQDs) directly integrated with CMOS circuits for high‐resolution short‐wave infrared (SWIR) imaging. By using double‐ended ligands on (100) facets of CQDs, suppression of bandtails and defects is achieved. The prepared CQD photodiodes exhibit excellent performance with low dark current and high responsivity, providing a promising solution for SWIR imaging applications.

After domestication, the expansions of rice landraces into the present-day range required a diverse array of adaptations to local environments, which included changes in daylight sensitivity, expanded thermal tolerance (for excess cold and heat), adaptations to water availability (drought and waterlogging), and resistance to biotic stresses (Garris et al., 2005; Glaszmann, 1987). The colour shading scale indicates minimum temperature in May. (g) Chilling tolerance response of rice varieties with the two COLDF alleles. (h) The frequency of the two COLDF alleles in wild and cultivated rice subgroups. (i–j) Mutations in the COLDF genomic region for TILLING (coldf-1; i) and gene editing (coldf-2; j) mutants and showed increased chilling sensitivity. (k) The cold tolerance response and survival rate of 14 varieties with COLDFtej and 19 accessions with COLDF other. To address the function of the Haptej allele, we performed cold treatments on 14 cultivated rice varieties with the Haptej allele and 19 cultivated rice varieties with the Hapother allele in a growth chamber, and the results showed that under cold stress (4 °C for 48 h), the survival rate was higher in rice varieties with the Haptej allele (93.25%) than those with the Hapother allele (10.12%; P = 1.66 × 10−13, two-tailed t-test) (Figure 1g,h,k).

Controlling credit risk is crucial for maintaining financial stability, and the role of geographic factors in this regard is a significant concern for scholars and policymakers. Drawing on the concept of information asymmetry, we developed a theoretical model to analyze how geographic factors influence credit risk. Our theoretical proposition suggests that the spatial organization of banks affects the efficiency of collecting and processing soft information, ultimately impacting the credit risk. To test this proposition, we collected microdata from Chinese commercial banks spanning the period from 2011 to 2022. Employing a mediating effect model, we empirically examined the relationship between spatial organizational structure and credit risk. Our results indicate that the distance between bank operations and functional distance impedes the collection and processing of soft information, thereby exacerbating credit risk in banks. The study focuses on examining how the spatial organizational structure of Chinese commercial banks affects credit risk. By analyzing geographic factors and information asymmetry, the study aims to understand how the organization of banks influences the collection and processing of soft information, which in turn impacts the credit risk. Furthermore, our analysis of the sample reveals that the mediating role of soft information varies between state-owned banks and joint-stock banks due to their distinct customer profiles. On the basis of these findings, we propose several policy recommendations, including a focus on enhancing the collection and processing of soft information, promoting the growth of locally based small and medium-sized banks, and reducing information barriers within bank hierarchies.

Background Corynebacterium striatum  was confirmed to be an important opportunistic pathogen, which could lead to multiple-site infections and presented high prevalence of multidrug resistance, particularly to quinolone antibiotics. This study aimed to investigate the mechanism underlying resistance to quinolones and the epidemiological features of 410 quinolone-resistant  C. striatum  clinical strains isolated from three tertiary hospitals in China. Methods A total of 410 C. striatum  clinical strains were isolated from different clinical samples of patients admitted to three tertiary teaching hospitals in China. Antibiotic susceptibility testing was performed using the microdilution broth method and pulsed-field gel electrophoresis (PFGE) was used for genotyping. Gene sequencing was used to identify possible mutations in the quinolone resistance-determining regions (QRDRs) of  gyrA . Results In total, 410 C. striatum  isolates were sensitive to vancomycin, linezolid, and daptomycin but resistant to ciprofloxacin. Depending on the antibiotic susceptibility testing results of 12 antimicrobial agents, the 410  C. striatum  strains were classified into 12 resistant biotypes; of these, the three biotypes R1, R2, and R3 were dominant and accounted for 47.3% (194/410), 21.0% (86/410), and 23.2% (95/410) of the resistant biotypes, respectively. Mutations in the QRDRs of gyrA  were detected in all quinolone-resistant  C. striatum  isolates, and 97.3% of the isolates (399/410) showed double mutations in codons 87 and 91 of the QRDRs of  gyrA . Ser-87 to Phe-87 and Asp-91 to Ala-91 double mutation in  C. striatum  was the most prevalent and accounted for 72.2% (296/410) of all mutations. Four new mutations in  gyrA  were identified in this study; these included Ser-87 to Tyr-87 and Asp-91 to Ala-91 (double mutation, 101 isolates); Ser-87 to Val-87 and Asp-91 toGly-91 (double mutation, one isolate); Ser-87 to Val-87 and Asp-91 to Ala-91 (double mutation, one isolate); and Ser-87 to Ile-87 (single mutation, one isolate). The minimum inhibitory concentration of ciprofloxacin for isolates with double (96.5%; 385/399) and single (72.7%; 8/11) mutations was high (≥ 32 µg/mL). Based on the PFGE typing results, 101 randomly selected  C. striatum  strains were classified into 50 genotypes (T01-T50), including the three multidrug-resistant epidemic clones T02, T06, and T28; these accounted for 14.9% (15/101), 5.9% (6/101), and 11.9% (12/101) of all genotypes, respectively. The multidrug-resistant T02 clone was identified in hospitals A and C and persisted from 2016 to 2018. Three outbreaks resulting from the T02, T06, and T28 clones were observed among intensive care unit (ICU) patients in hospital C between April and May 2019. Conclusions Quinolone-resistant  C. striatum  isolates showed a high prevalence of multidrug resistance. Point mutations in the QRDRs of  gyrA  conferred quinolone resistance to  C. striatum , and several mutations in  gyrA  were newly found in this study. The great clonal diversity, high-level quinolone resistance and increased prevalence among patients susceptible to  C. striatum  isolates deserve more attention in the future. Moreover, more thorough investigation of the relationship between quinolone exposure and resistance evolution in  C. striatum is necessary.

Genes have been lost or weakened from cultivated rice during rice domestication and breeding. Weedy rice ( Oryza sativa f. spontanea ) is usually recognized as the progeny between cultivated rice and wild rice and is also known to harbor an gene pool for rice breeding. Therefore, identifying genes from weedy rice germplasms is an important way to break the bottleneck of rice breeding. To discover genes from weedy rice germplasms, we constructed a genetic map based on w-hole-genome sequencing of a F 2 population derived from the cross between LM8 and a cultivated rice variety. We further identified 31 QTLs associated with 12 important agronomic traits and revealed that ORUFILM03g000095 gene may play an important role in grain length regulation and participate in grain formation. To clarify the genomic characteristics from weedy rice germplasms of LM8, we generated a high-quality genome assembly using single-molecule sequencing, Bionano optical mapping, and Hi-C technologies. The genome harbored a total size of 375.8 Mb, a scaffold N50 of 24.1 Mb, and originated approximately 0.32 million years ago (Mya) and was more closely related to Oryza sativa ssp. japonica . and contained 672 unique genes. It is related to the formation of grain shape, heading date and tillering. This study generated a high-quality reference genome of weedy rice and high-density genetic map that would benefit the analysis of genome evolution for related species and suggested an effective way to identify genes related to important agronomic traits for further rice breeding.

Novel antibacterial nanofiber/cotton hybrid yarns was fabricated by an efficient combination of a stepped pyramid stage free surface electrospinning and traditional cotton spinning process. In this study, nanofibers loading as well as the morphology variation of the nanofibers resulted from polymer solution concentration and applied voltage changes were investigated. The results demonstrated that the higher solution concentration led to larger nanofiber diameter, and higher applied voltage increased the loading of nanofibers in the hybrid yarns. Moreover, it was found that resultant nanofiber/cotton hybrid yarns which was contained a small amount of Triclosan, possessed excellent antibacterial activity against both Grampositive Staphylococcus aureus and Gram-negative Escherichia coli bacteria. This novel method is promising for the large scale production of antibacterial nanofiber/cotton hybrid yarns for biomedical and antibacterial textiles applications