Spark plasma sintering (SPS), also known as pulsed electric current sintering (PECS) or field-assisted sintering technique (FAST), belongs to a class of powder metallurgy techniques. In SPS, the ...sample is simultaneously subjected to a uniaxial pressure and electrical current in a vacuum or protective atmosphere. Although the fundamental principles of this procedure were first proposed over 50 years ago, SPS acquired major importance only within the last 20 years. Scholars come to realize that SPS technique enables control of the powder surface condition, atomic diffusion behavior, and phase stability and crystal growth behavior, as well as accelerating densification of hard-to-sinter materials. This review summarizes the latest research findings with respect to experimental procedures, densification behaviors, microstructural characteristics, and mechanical properties of various traditional and novel materials synthesized using SPS, mainly highlighting the heating mechanisms in SPS and the effects induced by multi-physical fields on materials. In addition, influences of operating parameters containing current, voltage, and uniaxial pressure on product characteristics are reviewed for a wide range of materialsincluding hard-to-sinter materials, carbon-containing materials, nanocrystalline materials, non-equilibrium materials, gradient materials, interconnect materials, complex shape materials, and advanced functional materials.
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•Effects of current, electric fields and pressure on SPS processing and micro-mechanisms in materials are investigated.•The state-of-the-art concepts of SPS devices for R&D and industrial application are presented.•The common technological superiority and optimization mechanisms of applying SPS in every material system are illustrated.•Overview on the design, experiment and simulation of both structural and functional materials developed by SPS technique.
Objective
To compare
Pneumocystis jirovecii
pneumonia (PJP) risk between patients with autoimmune rheumatic diseases (ARD) and the general population
Methods
We identified patients with ARD recorded ...in the National Health Insurance Research Database of Taiwan from 2002 to 2015 and randomly selected a comparison cohort from the general population matched for age and sex. We analyzed PJP risk stratified by sex, age, comorbidities, and medications using Cox proportional hazard model.
Results
We enrolled 103,117 patients with ARD. PJP risk significantly increased in patients with any ARD and with each individual ARD like rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), Sjogren’s syndrome (SjS), polymyositis and dermatomyositis (PM/DM), systemic sclerosis (SSc), and systemic vasculitis. Patients with PM/DM showed prominent risk with incidence rate of 12.47/100,000 patient year (95% confidence interval (CI), 32.16–86.70). In a time-dependent Cox proportional hazard model with comorbidities and medications as covariates, PM/DM, SSc, SLE, and SjS significantly increased adjusted hazard ratios (aHR) of 5.40, 5.12, 4.09, and 3.64, respectively (95% CI of 2.82–10.35, 2.16–12.13, 2.41–6.95, and 2.06–6.42, respectively). AHR after adjusting for male sex, cancer, human immunodeficiency virus infection (HIV), and interstitial lung disease also significantly increased. Use of daily oral steroid dose of >10 mg conferred the highest risk followed by mycophenolate. Use of injected steroids, cyclophosphamide, biological agents, methotrexate, and cyclosporine conferred a significantly higher risk.
Conclusion
Underlying ARD significantly predisposes patients to PJP, with PM/DM posing the highest threat. In addition to underlying disease, comorbidities and concomitant immunosuppressants are major risks. The strongest risk is recent daily steroid dose of >10 mg. Mycophenolate seems to be a more prominent risk factor than cyclophosphamide.
Key Points
• Autoimmune rheumatic diseases (ARD) significantly increased the overall risk of PJP, and so did each individual ARD.
• Use of steroids, mycophenolate, cyclophosphamide, biological agents, methotrexate, and cyclosporine all significantly increased risk of PJP.
• Male, elderly, malignancy, HIV, and interstitial lung disease are also related to increased risk of PJP.
• Underlying ARD, comorbidities, and use of immunosuppressant should all be considered in determining the overall risk of PJP.
Cancer cells are known for their capacity to rewire metabolic pathways to support survival and proliferation under various stress conditions. Ketone bodies, though produced in the liver, are not ...consumed in normal adult liver cells. We find here that ketone catabolism or ketolysis is re-activated in hepatocellular carcinoma （HCC） cells under nutrition deprivation conditions. Mechanistically, 3-oxoacid CoA-transferase 1 （OXCT1）, a rate-limiting ketolytic enzyme whose expression is suppressed in normal adult liver tissues, is re-induced by serum starvation-triggered mTORC2- AKT-SP1 signaling in HCC cells. Moreover, we observe that enhanced ketolysis in HCC is critical for repression of AMPK activation and protects HCC cells from excessive autophagy, thereby enhancing tumor growth. Importantly, analysis of clinical HCC samples reveals that increased OXCT1 expression predicts higher patient mortality. Taken together, we uncover here a novel metabolic adaptation by which nutrition-deprived HCC cells employ ketone bodies for energy supply and cancer progression.
Recycling precious elements from the electronic waste could be an environmental friendly way to avoid likely ecological damages caused by leaching of heavy metals and toxic elements as well as an ...economically attractive option to recover valuable materials that would otherwise be wasted. This research assessed the environmental and economic performance of recovering nine metal elements (aluminum (Al), copper (Cu), gold (Au), lead (Pb), nickel (Ni), silver (Ag), tin (Sn), zinc (Zn), and iron (Fe)) and two non-metal materials (resin and glass-fiber) from the waste printed circuit boards (PCBs), one of the vital components of electronic-waste (e-waste). SimaPro software was used to assess the environmental performance of recycling waste PCBs. Data were collected from recycling plants in Taichung City, Taiwan, and Eco-invent database was also used in the study. The impacts of metal recycling from PCBs were compared with the impacts caused by the mining of respective metals from their natural ores. Among the analyzed elements, only the recovery of Au from waste PCBs proved to have less environmental impacts than the mining from the natural ore. Among 16 environmental impact categories (ILCD midpoint 2011+ method of impact analysis) considered in the present study, cancer and non-cancer human toxicity were the most affected categories followed by minerals, fossils, and resource extraction. However, the economic analysis showed that the recycling of all elements from waste PCBs had a net positive benefit. When considering both the environment and economic performance, the recycling of Au proved to be a beneficial option.
•Recycling metals except gold had more negative environmental impacts than mining.•Copper recycling had the highest negative environmental impacts.•Gold recycling had the lower environmental impact than gold mining.•There was a net positive economic benefit for recycling of all metals.
Idiopathic pulmonary fibrosis (IPF) is characterized by fibrotic change in alveolar epithelial cells and leads to the irreversible deterioration of pulmonary function. Transforming growth factor-beta ...1 (TGF-β1)-induced epithelial-mesenchymal transition (EMT) in type 2 lung epithelial cells contributes to excessive collagen deposition and plays an important role in IPF. Atractylodin (ATL) is a kind of herbal medicine that has been proven to protect intestinal inflammation and attenuate acute lung injury. Our study aimed to determine whether EMT played a crucial role in the pathogenesis of pulmonary fibrosis and whether EMT can be utilized as a therapeutic target by ATL treatment to mitigate IPF. To address this topic, we took two steps to investigate: 1. Utilization of anin vitro EMT model by treating alveolar epithelial cells (A549 cells) with TGF-β1 followed by ATL treatment for elucidating the underlying pathways, including Smad2/3 hyperphosphorylation, mitogen-activated protein kinase (MAPK) pathway overexpression, Snail and Slug upregulation, and loss of E-cadherin. Utilization of an in vivo lung injury model by treating bleomycin on mice followed by ATL treatment to demonstrate the therapeutic effectiveness, such as, less collagen deposition and lower E-cadherin expression. In conclusion, ATL attenuates TGF-β1-induced EMT in A549 cells and bleomycin-induced pulmonary fibrosis in mice.
In this research, negative-charge carbon dots (CDs) were synthesized in one-step using a microwave and found to have potential antibacterial ability against multi-drug resistant bacteria. The CDs ...were synthesized by using citric acid and urea as precursors, and characterized by FT-IR, TEM and fluorescence spectrophotometry. The average size of CDs was about 2.5 nm, and the
ζ
potential was −11.06 mV. In the following antibacterial activity test, time-killing curve experiments and colony-forming assay were carried out to determine the minimum bactericidal concentration (MBC) and minimum inhibitory concentration (MIC) of the CDs against methicillin-resistant
Staphylococcus aureus
(MRSA) and vancomycin-intermediate
Staphylococcus aureus
(VISA). The data showed the MBC of the CDs against MRSA is 2.5 mg mL
−1
, and the MIC of the CDs against MRSA is 0.63 mg mL
−1
; the MBC of the CDs against VISA is 1.25 mg mL
−1
, and the MIC of the CDs against VISA is 0.63 mg mL
−1
. The results demonstrated that the negative-charge CDs have potential against multi-drug resistant
Staphylococcus aureus
(
S. aureus
), and may serve as alternatives for therapy in the future.
In this research, negative-charge carbon dots (CDs) were synthesized in one-step using a microwave and found to have potential antibacterial ability against multi-drug resistant bacteria.
The risk of bisphosphonate-related osteonecrosis of the jaw (BRONJ) in primary Sjogren syndrome (pSS) has rarely been explored. To explore the association between BRONJ and pSS, we conducted a ...population-based propensity-score-matched cohort study using Taiwan's National Health Insurance Research Database, including pSS patients receiving antiosteoporotic therapy and patients without pSS receiving antiosteoporotic therapy. A 1:4 matched-pair cohort based on propensity score was created. The stratified Cox proportional hazards model compared the risk of BRONJ in the pSS and non-pSS groups. In the study, 23,280 pSS patients and 28,712,152 controls were enrolled. After matching, 348 patients with pSS receiving antiosteoporotic drugs and 50,145 without pSS receiving antiosteoporotic drugs were included for analysis. The risk of developing BRONJ was 1.96 times higher in pSS patients compared with non-pSS patients after adjustment for age, sex, and comorbidities. No dose-response effect was observed in the bisphosphonate-treated pSS cohorts, documented as the cumulative defined daily doses of either < 224 or ≥ 224 (hazard ratio HR: 2.407, 95% confidence interval CI 1.412-7.790; HR: 2.143, 95% CI 1.046-4.393, respectively) increased risk of developing osteonecrosis of the jaw. In conclusion, the risk of BRONJ is significantly higher in patients with pSS compared with the general population.
Aim: Although a lower level of non-high-density lipoprotein cholesterol (HDL-C) was reported to be inversely associated with spontaneous intracranial hemorrhage (ICH), no enough evidence has verified ...whether lipid profiles modify hemorrhagic transformation and functional outcomes in patients with acute ischemic treated with thrombolysis.Methods: This multicenter cohort study included 2373 patients with acute ischemic stroke treated with intravenous thrombolysis between December 2004 and December 2016. Of these, 1845 patients were categorized into either the hyperlipidemia or non-hyperlipidemia group. Symptomatic ICH (SICH) rates within 24-36 h of thrombolytic onset and functional outcomes at 30 and 90 days were longitudinally surveyed. Models of predicting hemorrhagic transformation were used to validate our findings.Results: For enrolled 1845 patients, SICH rates were ≥2-fold reduced for the hyperlipidemia group by the NINDS (adjusted RR: 0.488 0.281–0.846, p=0.0106), the ECASS II (adjusted RR: 0.318 0.130-0.776, p=0.0119), and SITS-MOST standards (adjusted RR: 0.214 0.048-0.957, p=0.0437). The favorable functional rates between the two groups were not significantly different. Lower levels of LDL-C were showed in robust association with SICH. With a cut-off LDL-C value of ＜130 mg/dL, new models are more robust and significant in predicting hemorrhagic transformation within 24-36 h.Conclusions: This study supports the strong association between reduced LDL-C and increased SICH, but not for functional outcomes in patients with acute ischemic stroke treated with intravenous thrombolysis. LDL-C level of ＜130 mg/dL is supposed to a candidate marker for predicting SICH within 24-36 h.
MicroRNAs (miRNAs), small non-coding RNAs of 19 to 25 nt, play important roles in gene regulation in both animals and plants. In the last few years, the oligonucleotide microarray is one ...high-throughput and robust method for detecting miRNA expression. However, the approach is restricted to detecting the expression of known miRNAs. Second-generation sequencing is an inexpensive and high-throughput sequencing method. This new method is a promising tool with high sensitivity and specificity and can be used to measure the abundance of small-RNA sequences in a sample. Hence, the expression profiling of miRNAs can involve use of sequencing rather than an oligonucleotide array. Additionally, this method can be adopted to discover novel miRNAs.
This work presents a systematic approach, miRExpress, for extracting miRNA expression profiles from sequencing reads obtained by second-generation sequencing technology. A stand-alone software package is implemented for generating miRNA expression profiles from high-throughput sequencing of RNA without the need for sequenced genomes. The software is also a database-supported, efficient and flexible tool for investigating miRNA regulation. Moreover, we demonstrate the utility of miRExpress in extracting miRNA expression profiles from two Illumina data sets constructed for the human and a plant species.
We develop miRExpress, which is a database-supported, efficient and flexible tool for detecting miRNA expression profile. The analysis of two Illumina data sets constructed from human and plant demonstrate the effectiveness of miRExpress to obtain miRNA expression profiles and show the usability in finding novel miRNAs.
To achieve the goal of carbon emission reduction, a number of countries have implemented carbon tax policies, and carbon pricing has become an important tool. This paper discusses the interactions ...between a government and an enterprise for implementing carbon taxes over time or by level of tax, considering greenhouse gas emission. We examine the impacts of various carbon tax policies on enterprises' investments in new technology, their reductions in production quantity, and governments' tax remittances. A case study of the strategic responses of three firms in Taiwan's electronics, cement, and steel industries to two carbon emission policies promulgated by government shows that appropriate levels of tax can induce an enterprise to alter its production processes to achieve emission reduction as part of a long-term business strategy.
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