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A S135 drill pipe experienced severe corrosion failure only after several cycles in a well. In this paper, a series of experiments were conducted to analyze the causes of corrosion failure of drill pipe, including nondestructive testing, chemical and physical properties, macroscopic and microscopic analysis, and X-ray diffraction (XRD) analysis. The results showed that the corrosion failure of the external thread joint and pipe body of the S135 drill pipe belonged to oxygen corrosion, and a large amount of Cl− in the environmental medium accelerates the corrosion. The external threaded joint of the drill pipe was more severely corroded than pipe body due to the following two reasons. Firstly, vortexing flow was easy to form at the drill pipe joints with single shoulder threads. Secondly, the drill pipe external thread joint had 3.0-grade banded structure segregation, forming a local small electrode potential difference. [ABSTRACT FROM AUTHOR]

Aims: Recent research has suggested that microbial necromass has a disproportionate influence on soil organic C accumulation. But few field studies have followed the bacterial and fungal necromass changes during plant residue decomposition. How bacterial and fungal necromass drives soil C fractions; what role of soil C fractions play; and the critical factors which influence their formation have remained poorly understood. Methods: In a 512-days culture experiment with a perennial C3 herb (St.B, S. bungeana) we traced the formation of muramic acid (MurA) vs. Glucosamine (GluN), and investigated the relationships between MurA, GluN and soil C fractions. Results: The results showed that the bacteria community dominates the decomposition process due to soil pH (> 7) and microbial metabolic C-, P-limitations. The dynamics of bacterial necromass over the time-course of the experiment changed from fluctuating variations to a significant increase. This means that the bacterial necromass has been in a balance of accumulation and decomposition at early and middle periods. Significant accumulation only occurred in the later stages, which was attributed to the involvement of bacteria in more microbial necromass degradation. In this process, the entombing effect of bacterial necromass was more dramatic than their metabolic consumption. While in the case of microbial metabolism limitation, fungal necromass will lose its physicochemical protection of the mineral particles, and thus be degraded and utilized. The priming effecting caused by the one-time input of plant residues with high C/N ratios and soil mineralization resulted in the absence of SOC accumulation in the short term. Microorganisms regulate the turnover of POC, MAOC and MBC by microbial biomass and necromass. The utilization of soil C fractions is the direct cause of SOC decline, while the turnover of microbial necromass only plays an indirect role. Soil pH and microbial biomass stoichiometry as the critical factors in changes in bacterial and fungal necromass. Lower living microbial biomass production and the dynamics of microbial necromass indicate that microbial necromass is constantly broken down as an available C source. Conclusions: With the synergistic effect of soil C fractions, the production of microbial biomass and the degradation of cellular residues maintain microbial stoichiometric homeostasis. In addition to soil pH, microbial biomass stoichiometry co-determines microbial necromass formation. [ABSTRACT FROM AUTHOR]

The genetic transcription profile of brain ischemic and reperfusion injury remains elusive. To address this, we used an integrative analysis approach including differentially expressed gene (DEG) analysis, weighted-gene co-expression network analysis (WGCNA), and pathway and biological process analysis to analyze data from the microarray studies of nine mice and five rats after middle cerebral artery occlusion (MCAO) and six primary cell transcriptional datasets in the Gene Expression Omnibus (GEO). (1) We identified 58 upregulated DEGs with more than 2-fold increase, and adj. p < 0.05 in mouse datasets. Among them, Atf3, Timp1, Cd14, Lgals3, Hmox1, Ccl2, Emp1, Ch25h, Hspb1, Adamts1, Cd44, Icam1, Anxa2, Rgs1, and Vim showed significant increases in both mouse and rat datasets. (2) Ischemic treatment and reperfusion time were the main confounding factors in gene profile changes, while sampling site and ischemic time were not. (3) WGCNA identified a reperfusion-time irrelevant and inflammation-related module and a reperfusion-time relevant and thrombo-inflammation related module. Astrocytes and microglia were the main contributors of the gene changes in these two modules. (4) Forty-four module core hub genes were identified. We validated the expression of unreported stroke-associated core hubs or human stroke-associated core hubs. Zfp36 mRNA was upregulated in permanent MCAO; Rhoj, Nfkbiz, Ms4a6d, Serpina3n, Adamts-1, Lgals3, and Spp1 mRNAs were upregulated in both transient MCAO and permanent MCAO; and NFKBIZ, ZFP3636, and MAFF proteins, unreported core hubs implicated in negative regulation of inflammation, were upregulated in permanent MCAO, but not in transient MCAO. Collectively, these results expand our knowledge of the genetic profile involved in brain ischemia and reperfusion, highlighting the crucial role of inflammatory disequilibrium in brain ischemia. [ABSTRACT FROM AUTHOR]

Objective: To evaluate image quality and diagnostic confidence improvement using a thin slice and a deep learning image reconstruction (DLIR) in contrast-enhanced abdominal CT. Methods: Forty patients with hepatic lesions in enhanced abdominal CT were retrospectively analyzed. Images in the portal phase were reconstructed at 5 mm and 1.25 mm slice thickness using the 50% adaptive statistical iterative reconstruction (ASIR-V) (ASIR-V50%) and at 1.25 mm using DLIR at medium (DLIR-M) and high (DLIR-H) settings. CT number and standard deviation of the hepatic parenchyma, spleen, portal vein, and subcutaneous fat were measured, and contrast-to-noise ratio (CNR) was calculated. Edge-rise-slope (ERS) was measured on the portal vein to reflect spatial resolution and the CT number skewness on liver parenchyma was calculated to reflect image texture. Two radiologists blindly assessed the overall image quality including subjective noise, image contrast, visibility of small structures using a 5-point scale, and object sharpness and lesion contour using a 4-point scale. Results: For the 1.25-mm images, DLIR significantly reduced image noise, improved CNR and overall subjective image quality compared to ASIR-V50%. Compared to the 5-mm ASIR-V50% images, DLIR images had significantly higher scores in the visibility and contour for small structures and lesions; as well as significantly higher ERS and lower CT number skewness. At a quarter of the signal strength, the 1.25-mm DLIR-H images had a similar subjective noise score as the 5-mm ASIR-V50% images. Conclusion: DLIR significantly reduces image noise and maintains a more natural image texture; image spatial resolution and diagnostic confidence can be improved using thin slice images and DLIR in abdominal CT. Key Points: • DLIR further reduces image noise compared with ASIR-V while maintaining favorable image texture. • In abdominal CT, thinner slice images improve image spatial resolution and small object visualization but suffer from higher image noise. • Thinner slice images combined with DLIR in abdominal CT significantly suppress image noise for detecting low-density lesions while significantly improving image spatial resolution and overall image quality. [ABSTRACT FROM AUTHOR]

Background and Objective: Pembrolizumab plus cisplatin and fluorouracil demonstrated superior efficacy and comparable safety compared with fluorouracil and cisplatin (FP) as first-line treatment for locally advanced unresectable or metastatic carcinoma of the esophagus and gastroesophageal junction adenocarcinoma in a phase III trial (KEYNOTE-590). This study evaluated the cost effectiveness of pembrolizumab plus FP versus FP and versus a blended chemotherapy comparator including FP, carboplatin plus paclitaxel, FOLFOX, FOLFIRI, docetaxel plus FP, trastuzumab plus FP, and trastuzumab plus FOLFOX from a US healthcare payer's perspective. Methods: A partitioned survival model was developed with three health states (progression-free, progressive disease, and death). Overall survival, progression-free survival, time on treatment, and adverse events were informed by patient-level data from KEYNOTE-590. The blended chemotherapy comparator reflected the current US treatment landscape and was assumed to have similar efficacy and safety as FP. Health utilities were estimated using linear mixed-effects models based on EQ-5D-5L data from the trial. Resource use and cost inputs (2020 US dollars) were based on US standard sources and literature. Costs, life-years, and quality-adjusted life-years (QALYs) discounted at 3.0% per year and incremental cost-effectiveness ratio were outcomes in the model. Sensitivity and scenario analyses were conducted to assess the robustness of base-case results. Results: Compared with FP, pembrolizumab plus FP produced a mean gain of 0.86 life-year and 0.77 QALY with additional costs of $112,630 over 37.6 years, yielding an incremental cost-effectiveness ratio of $147,097 per QALY. Results were similar when the intervention was pembrolizumab plus alternative chemotherapies or when blended chemotherapy became the comparator. Results were most sensitive to different overall survival extrapolation approaches. Conclusions: Our analysis suggests that pembrolizumab plus chemotherapy extended life-years and QALYs and is cost effective compared with chemotherapy alone as a first-line treatment for advanced esophageal cancer in the USA given a willingness-to-pay threshold of $150,000 per QALY. [ABSTRACT FROM AUTHOR]

Background: Tribendimidine is a new anthelmintic agent synthesized by Chinese scientists. It is a broad spectrum agent with high activity against parasites. However, its disposition and metabolism remain unknown. Objective: To investigate the metabolism, disposition, and metabolites of tribendimidine in healthy human volunteers. Methods: Twelve healthy Chinese volunteers were chosen after clinical assessment of health status and laboratory tests. They received single oral doses of tribendimidine 400mg enteric-coated tablets. Blood and urine samples were collected at scheduled timepoints. Samples were qualitatively and quantitatively analyzed by liquid chromatography-mass spectrometric (LC-MS) and high performance liquid chromatography (HPLC) methods, respectively. Results: Tribendimidine was rapidly and completely broken down to p-(1-dimethylamino ethylimino) aniline (dADT) and terephthalaldehyde (TPAL). Furthermore, dADT was partially transformed to acetylated dADT, and TPAL completely transformed to terephalic acid (TPAC). The main pharmacokinetic parameters (± SD) of dADT were as follows: elimination half life (t½) 4.74 ± 1.80 h; elimination rate constant (Ke) 0.16 ± 0.06 h-1; apparent volume of distribution (Vd/F) 12.23 ± 8.69L · kg-1; apparent total clearance of the drug from plasma (CL/F) 1.63 ± 0.58L · h-1 kg-1; area under the plasma concentration-time curve (AUC) from time 0 to time 24 hours (AUC24) 4.29 ± 1.88 µg · mL-1 · h; AUC from time zero to infinity (AUC∞) 4.45 ± 1.81 µg · mL-1 h; maximum plasma drug concentration (Cmax) 0.64 ± 0.27 µg · mL-1; and time to Cmax (tmax) 4.20 ± 0.71 h. A total of 35.28% dADT and 28.50% TPAC were excreted through the urine within 24 hours after tribendimidine administration. Conclusion: These results reveal the disposition, metabolism, and main metabolites of tribendimidine in healthy Chinese volunteers. [ABSTRACT FROM AUTHOR]