This article presents the high temperature tensile and creep behaviors of a novel high entropy alloy (HEA). The microstructure of this HEA resembles that of advanced superalloys with a high entropy ...FCC matrix and L1
ordered precipitates, so it is also named as "high entropy superalloy (HESA)". The tensile yield strengths of HESA surpass those of the reported HEAs from room temperature to elevated temperatures; furthermore, its creep resistance at 982 °C can be compared to those of some Ni-based superalloys. Analysis on experimental results indicate that HESA could be strengthened by the low stacking-fault energy of the matrix, high anti-phase boundary energy of the strengthening precipitate, and thermally stable microstructure. Positive misfit between FCC matrix and precipitate has yielded parallel raft microstructure during creep at 982 °C, and the creep curves of HESA were dominated by tertiary creep behavior. To the best of authors' knowledge, this article is the first to present the elevated temperature tensile creep study on full scale specimens of a high entropy alloy, and the potential of HESA for high temperature structural application is discussed.
Summary Klebsiella pneumoniae is a well known human nosocomial pathogen. Most community-acquired K pneumoniae infections cause pneumonia or urinary tract infections. During the past two decades, ...however, a distinct invasive syndrome that causes liver abscesses has been increasingly reported in Asia, and this syndrome is emerging as a global disease. In this Review, we summarise the clinical presentation and management as well the microbiological aspects of this invasive disease. Diabetes mellitus and two specific capsular types in the bacterium predispose a patient to the development of liver abscesses and the following metastatic complications: bacteraemia, meningitis, endophthalmitis, and necrotising fasciitis. For patients with this invasive syndrome, appropriate antimicrobial treatment combined with percutaneous drainage of liver abscesses increases their chances of survival. Rapid detection of the hypervirulent strain that causes this syndrome allows earlier diagnosis and treatment, thus minimising the occurrence of sequelae and improving clinical outcomes.
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•A herb-based formula delivers positive clinical outcomes on COVID-19 patients.•The formula inhibits SARS-CoV-2 pathogenesis in anti-viral & -inflammatory assays.•Real-world-evidence ...offers insights to inform drug development.•Bed-to-bench approach shortens the time required for finding effective therapeutics.
COVID-19 is a global pandemic, with over 50 million confirmed cases and 1.2 million deaths as of November 11, 2020. No therapies or vaccines so far are recommended to treat or prevent the new coronavirus. A novel traditional Chinese medicine formula, Taiwan Chingguan Yihau (NRICM101), has been administered to patients with COVID-19 in Taiwan since April 2020. Its clinical outcomes and pharmacology have been evaluated. Among 33 patients with confirmed COVID-19 admitted in two medical centers, those (n = 12) who were older, sicker, with more co-existing conditions and showing no improvement after 21 days of hospitalization were given NRICM101. They achieved 3 consecutive negative results within a median of 9 days and reported no adverse events. Pharmacological assays demonstrated the effects of the formula in inhibiting the spike protein/ACE2 interaction, 3CL protease activity, viral plaque formation, and production of cytokines interleukin (IL)-6 and tumor necrosis factor (TNF)-α. This bedside-to-bench study suggests that NRICM101 may disrupt disease progression through its antiviral and anti-inflammatory properties, offering promise as a multi-target agent for the prevention and treatment of COVID-19.
•N protein mutations in the B.1.1.7 variant of concern may escape antigenic test detection.•Paired rapid antigen tests and molecular diagnostic methods are needed.•False-negative results could be ...rapidly corrected with RT-PCR.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a pandemic. Diagnostic testing for SARS-CoV-2 has continuously been challenged due to several variants with diverse spike (S) and nucleocapsid (N) protein mutations . SARS-CoV-2 variant proliferation potentially affects N protein-targeted rapid antigen testing. In this study, rapid antigen and reverse transcription PCR (RT-PCR) tests were performed simultaneously in patients with suspected coronavirus disease 2019 (COVID-19). Direct whole genome sequencing was performed to determine the N protein variations, and the viral assemblies were uploaded to GISAID. The genomes were then compared with those of global virus strains from GISAID. These isolates belonged to the B.1.1.7 variant, exhibiting several amino acid substitutions, including D3L, R203K, G204R, and S235F N protein mutations. The T135I mutation was also identified in one variant case in which the rapid antigen test and RT-PCR test were discordantly negative and positive, respectively. These findings suggest that the variants undetected by the Panbio COVID-19 rapid antigen test may be due to the T135I mutation in the N protein, posing a potential diagnostic risk for commercially available antigen tests. Hence, we recommend concomitant paired rapid antigen tests and molecular diagnostic methods to detect SARS-CoV-2. False-negative results could be rapidly corrected using confirmatory RT-PCR results to prevent future COVID-19 outbreaks.
The Omicron variant of concern (VOC) has surged in many countries and replaced the previously reported VOC. To identify different Omicron strains/sublineages on a rapid, convenient, and precise ...platform, we report a novel multiplex real‐time reverse transcriptase polymerase chain reaction (RT‐PCR) method in one tube based on the Omicron lineage sequence variants' information. Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) subvariants were used in a PCR‐based assay for rapid identification of Omicron sublineage genotyping in 1000 clinical samples. Several characteristic mutations were analyzed using specific primers and probes for the spike gene, del69–70, and F486V. To distinguish Omicron sublineages (BA.2, BA.4, and BA.5), the NSP1:141–143del in the ORF1a region and D3N mutation in membrane protein occurring outside the spike protein region were analyzed. Results from the real‐time PCR assay for one‐tube accuracy were compared to those of whole genome sequencing. The developed PCR assay was used to analyze 400 SARS‐CoV‐2 positive samples. Ten samples determined as BA.4 were positive for NSP1:141–143del, del69–70, and F486V mutations; 160 BA.5 samples were positive for D3N, del69–70, and F486V mutations, and 230 BA.2 samples were without del69–70. Screening these samples allowed the identification of epidemic trends at different time intervals. Our novel one‐tube multiplex PCR assay was effective in identifying Omicron sublineages.
The microstructure and high temperature hardness of two face‐centered cubic high entropy Ni‐based alloys with L12 γ′ precipitates have been studied. Both alloys exhibit higher mixing entropy and with ...the advantages in lower density and lower cost of raw materials than conventional Ni‐based superalloys. Their γ′ solvus are above 1 150 °C, and the γ–γ′ microstructure can be thermodynamically stable after isothermal ageing from 700 to 1 100 °C for at least 500 h. By XRD peak deconvolution, positive lattice misfits between γ and γ′ have been shown till elevated temperatures. The results from nano‐indentation test indicate that their highly alloyed γ′ phase have rendered more significant strengthening, and the underlying mechanism can be attributed to the higher anti‐phase boundary energy. Therefore, with minor refractory additions, the bulk hardness of present alloys can surpass that of commercial superalloy from room to high temperature.
The microstructure and high temperature hardness of two FCC high entropy Ni‐based alloys with γ′ precipitates have been studied. Their microstructure can be thermal stable from inter‐mediate to high temperatures. With minor refractory additions, the room to high temperature hardness of present alloys can surpass that of conventional superalloy due to more significant strengthening from the highly alloyed γ′ phase.
Aims and Objectives
To investigate the factors affecting quality of life in healthcare providers who care for patients with COVID‐19.
Background
Healthcare providers caring for COVID‐19 patients ...during the pandemic suffered a deterioration in their quality of life. Several studies have explored their psychological impact of working with COVID patients, but none have examined the causes of this deterioration.
Design
A cross‐sectional study.
Methods
In the current study, the authors investigated the factors affecting quality of life in 293 healthcare providers recruited from a medical centre in northern Taiwan who had recently cared for patients with suspected or confirmed COVID‐19 by analysing their responses to an online self‐report questionnaire, using bivariate correlations and structural equation modelling. Reporting of this research adheres to the STROBE guideline.
Results
The study identified an important sequence of factors that mediated the effects of perceived success of epidemic prevention policies, family relations problems and education level on quality of life in a sample of healthcare workers caring for COVID‐19 patients. The mediators were use of approach‐oriented coping strategies and current mental health status. Specifically, use of approach‐oriented coping strategies was found to directly cause improved quality of life and indirectly cause improved mental health, whereas use of avoidant coping strategies was found to directly cause worsening of mental health. Poor mental health predicted poor quality of life.
Conclusions
Results suggest that implementation of sound epidemic prevention policies that promote adoption of approach‐oriented coping behaviour should lead to a better quality of life in the future for healthcare providers working in challenging circumstances.
Relevance to Clinical Practice
Assessment of these policies as well as the providers' family relations are necessary first steps to improving the success of approach‐oriented coping behaviour in this population, which in turn can improve their mental health and quality of life.
Patient or Public Contribution
Neither patients nor members of the public were involved in the design or execution of the study.
Background and Aim
This study investigated whether hepatitis B surface antigen (HBsAg) could predict hepatitis B virus (HBV) relapse after cessation of entecavir or tenofovir disoproxil fumarate ...(TDF) prophylaxis for chronic hepatitis B cancer patients who are undergoing chemotherapy.
Methods
The study enrolled 122 hepatitis B e‐antigen‐negative cancer patients who underwent chemotherapy with entecavir or TDF for antiviral prophylaxis and posttreatment follow‐up for at least 6 months.
Results
Of the 122 patients, 52 and 18 experienced virological and clinical relapse, which had 3‐year cumulative incidences of 46.6% and 18.6%, respectively. Multivariate analysis showed that end‐of‐treatment HBsAg levels and baseline HBV‐DNA ≥ 2000 IU/mL were independent predictors of virological relapse. The best HBsAg cutoff value was 500 IU/mL. An end‐of‐treatment HBsAg of 500 IU/mL was useful for predicting virological relapse in patients with baseline HBV‐DNA < 2000 IU/mL (3‐year rate: 21.3% vs 46.4%, P = 0.038, in patients with HBsAg < 500 and ≥ 500 IU/mL, respectively), but not in patients with baseline HBV‐DNA ≥ 2000 IU/mL. Of the 52 patients who experienced virological relapse, 13 experienced transient virological relapse. Patients with baseline HBV‐DNA level < 2000 IU/mL experienced a higher rate of transient virological relapse (42.1% vs 15.2%, P = 0.031). Three patients experienced hepatic decompensation upon alanine aminotransferase flares, and no patient died after timely retreatment. Ten patients experienced posttreatment HBsAg loss, and the 3‐year HBsAg loss rate was 30.7% in patients with end‐of‐treatment HBsAg < 100 IU/mL.
Conclusions
The baseline HBV‐DNA and end‐of‐treatment HBsAg levels could predict virological relapse after withdrawal of entecavir and TDF prophylaxis for chemotherapy.
The present work investigates the high temperature oxidation and corrosion behaviour of high entropy superalloys (HESA). A high content of various solutes in HESA leads to formation of complex ...oxides, however the Cr and Al activities of HESA are sufficient to promote protective chromia or alumina formation on the surface. By comparing the oxidation and corrosion resistances of a Ni-based superalloy—CM247LC, Al2O3-forming HESA can possess comparable oxidation resistance at 1100 °C, and Cr2O3-forming HESA can exhibit superior resistance against hot corrosion at 900 °C. This work has demonstrated the potential of HESA to maintain surface stability in oxidizing and corrosive environments.
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