For conical indentation, the strain energy is a function of the semi-vertical cone angle, the indentation depth and the stress-strain relation. According to equivalent energy principle of ...representative volume elements (RVE) and the classical cavity assumption for material deformation region, the function with dual-parameters about volume and deformation is theoretically derived in the present study. This original equivalent-energy indentation model (EIM) is capable of forward-predicting load-depth relation and reverse-predicting uniaxial stress-strain relation for ductile materials only based on loading part of indentation. Further analyses show that the forward and reverse predicted results from EIM method are in excellent agreement with those by finite element analyses (FEA). Macro conical indentation experiments on five types of metals have been conducted using conventional indenters which are similar to Rockwell sclerometer. Consequently, the stress-strain relations predicted by EIM are quite close to those from standard tensile tests.
Display omitted
All-trans retinoic acid (ATRA), an active metabolite of vitamin A, plays important roles in cell proliferation, cell differentiation, apoptosis, and embryonic development. The effects of ATRA are ...mediated by nuclear retinoid receptors as well as non-genomic signal pathway, such as MAPK and PKA. The great success of differentiation therapy with ATRA in acute promyelocytic leukemia (APL) not only improved the prognosis of APL but also spurred the studies of ATRA in the treatment of other tumors. Since the genetic and physiopathological simplicity of APL is not common in human malignancies, the combination of ATRA with other agents (chemotherapy, epigenetic modifiers, and arsenic trioxide, etc) had been extensively investigated in a variety of tumors. In this review, we will discuss in details about ATRA and its role in cancer treatment.
The EIM (equivalent-energy indentation method) based on equivalent energy principle is proposed to determine the stress-strain relations of materials via spherical indentation. For various materials ...in power hardening law, plenty of finite element simulations were conducted to verify this novel method. The numerical verification shows the forward-predicted load-depth curves and the reverse-predicted stress-strain curves by EIM agree with the results from FEA (finite element analysis). For different light alloys, the stress-strain curves predicted by the method are consistent with the tensile results of the alloys. Additionally, a comparison between EIM and the existing ABI (automatic ball indentation) is conducted as well.
Display omitted
•Based on EEP, the EIM correlating strain energy, depth, tip diameter and Hollomon parameters is proposed.•For wide range of imaginary materials, forward-predictions and reverse-predictions from EIM agree well with FEA results.•For various light alloys, tensile properties predicted by EIM are closed to those from tensile tests.
Based on the power-law stress–strain relation and equivalent energy principle, theoretical equations for converting between Brinell hardness (HB), Rockwell hardness (HR), and Vickers hardness (HV) ...were established. Combining the pre-existing relation between the tensile strength (
σ
b
) and Hollomon parameters (
K
,
N
), theoretical conversions between hardness (HB/HR/HV) and tensile strength (
σ
b
) were obtained as well. In addition, to confirm the pre-existing
σ
b
-(
K
,
N
) relation, a large number of uniaxial tensile tests were conducted in various ductile materials. Finally, to verify the theoretical conversions, plenty of statistical data listed in ASTM and ISO standards were adopted to test the robustness of the converting equations with various hardness and tensile strength. The results show that both hardness conversions and hardness-strength conversions calculated from the theoretical equations accord well with the standard data.
•This work reviews advances of bio-carbon KIBs anode with diverse microstructures.•A discussion on biomass carbons and biomass carbon-metal composites are presented.•The geometries, synthesis, and ...electrochemical characteristics are both summarized.•Investigations on the electrochemical kinetics of bio-carbon KIBs anode are provided.•Perspectives to achieve structurally-tuned bio-carbon KIBs anode are highlighted.
Pursuit of advanced batteries with high energy density and low cost is the eternal goal for electrochemists. Potassium-ion batteries (KIBs) become a core focus to meet the need for scalable power sources in both academic and industrial energy-harvesting area. As the key to boosting development of KIBs, the advancement of high-performance anode materials helps to increase their competitiveness and feasibility. In this sense, biomass-based carbon materials with elaborate biological structures, strong physicochemical adsorptions, environmental benignity and cost effectiveness tick almost all the right boxes as a material for biocompatible energy-storage systems. More importantly, their intrinsic diversity of bio-microstructures provide considerable merits involving rapid ion/electron channels, strengthened mechanical substrates as well as in-situ templates for further electrode designs, allowing for achieving structurally-tuned surface chemistry in KIBs anodes. In this review, by focusing on the aspects of pure biomass carbons and biomass carbon-metal composites, a rapid glimpse at biomass carbon-based anode materials with various micro-architectures is provided, covering the architectural geometries, synthetic strategies, energy-storing mechanisms and electrochemical characteristics. In addition, a brief perspective on the imminent challenges and future directions of bio-carbon anodes in KIBs is also highlighted. We hope to cast a valuable outlook for structurally-controlled biomass-based anode materials in KIBs.
Unique coumarin aminophosphonates as new antibacterial agents were designed and synthesized to combat severely bacterial resistance. Bioactivity assessment identified that 3-hydroxylphenyl ...aminophosphonate 6f with low hemolytic activity not only exhibited excellent inhibition potency against Staphylococcus aureus at low concentration (0.5 μg/mL) in vitro but also showed considerable antibacterial potency in vivo. Meanwhile, the active compound 6f was capable of eradicating the S. aureus biofilm, thus alleviating the development of S. aureus resistance. Furthermore, the drug combination of compound 6f with norfloxacin could enhance the antibacterial efficacy. Mechanistic explorations manifested that molecule 6f was able to destroy the integrity of cell membrane, which resulted in the leakage of protein and metabolism inhibition. The cellular redox homeostasis was interfered through inducing the generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS), leading to the reduction of glutathione (GSH) activity and lipid peroxidation. Furthermore, compound 6f could intercalate into DNA base pair to hinder normal biological function. The above results provided powerful information for the further development of coumarin aminophosphonates as antibacterial agents.
Display omitted
•Unique coumarin aminophosphonates with potent antibacterial efficacy were developed.•Molecule 6f exerted low toxicity, no obvious resistance and good bioavailability.•Compound 6f could disturb the membrane integrity and lead to the leakage of intracellular materials.•Compound 6f could induce oxidative damage and restrain metabolism.
Unique coumarin conjugates with thiazolidinone as novel structural antibacterial modulators were exploited to combat the lethal multidrug-resistant bacterial infections. Bioactivity evaluation ...identified that indole-incorporated coumarin thiazolidinone conjugate 14a with low cytotoxicity to mammalian cells showed a broad antibacterial spectrum and exerted potent inhibition efficiencies to the tested germs at low concentrations (0.25–2 μg/mL). Moreover, the favorable performance of 14a in eradicating bacterial biofilm was beneficial to avert developing drug resistance. Mechanistic explorations revealed that molecule 14a was able to destroy cell membrane, leading to the leakage of intracellular materials and metabolism inhibition. The accumulation of excess reactive oxygen species (ROS) mediated by compound 14a could impede glutathione (GSH) activity and induce lipid peroxidation to suppress bacteria growth. Furthermore, compound 14a could not only intercalate into DNA base pair but also take part in non-covalent interaction with DNA gyrase B to hinder their biological function. Quantum chemical study indicated that molecule 14a had low HOMO-LUMO energy gap, which resulted in more stabilizing interactions and was conducive to displaying better antibacterial activity. ADMET analysis manifested that 14a possessed promising pharmacokinetic properties.
Display omitted
•Novel thiazolidinone-conjugated coumarins with broad antibacterial spectrum were developed.•Compound 14a performed better inhibition efficacy than norfloxacin.•Molecule 14a exerted low toxicity, no obvious resistance and good bioavailability.•Compound 14a could disturb the membrane integrity and lead to the leakage of intracellular materials.•Compound 14a could restrain metabolism and induce oxidative damage.
In this paper, a multi-wavelength fiber ring laser (MWFRL) based on a hybrid gain medium and Sagnac interferometer (SI) used for temperature measurement has been proposed and experimentally ...demonstrated. Experiments have been carried out with polarization maintaining fibers (PMF) of different lengths, which are incorporated in the SI as sensing elements. Stable multi-wavelength oscillation at 1560 nm band is successfully achieved with the wavelength instability of ±0.08 nm and the signal-to-noise of 42 dB. The experimental results show that the wavelength change of the MWFRL with temperature variation has a good linear response and the temperature sensitivity of 1.8063 ± 0.00933 nm/
C is obtained when the length of the PMF is 1.7 m. As the length of PMF increases, the sensitivity can be improved.
Holistic health care (HHC) is a synonym for complete patient care, and as such an efficient clinical decision support system (CDSS) for HHC is critical to support the judgement of physician’s ...decision in response of patient’s physical, emotional, social, economic, and spiritual needs. The field of artificial intelligence (AI) has evolved considerably in the past decades and many AI applications have been deployed in various contexts. Therefore, this study aims to propose an AI-assisted CDSS model that predicts patients in need of HHC and applies an improved recurrent neural network (RNN) model, long short-term memory (LSTM) for the prediction. The data sources include in-patient’s comorbidity status and daily vital sign attributes such as blood pressure, heart rate, oxygen prescription, etc. A two-year dataset consisting of 121 thousand anonymized patient cases with 890 thousand physiological medical records was obtained from a medical center in Taiwan for system evaluation. Comparing with the rule-based expert system, the proposed AI-assisted CDSS improves sensitivity from 26.44% to 80.84% and specificity from 99.23% to 99.95%. The experimental results demonstrate that an AI-assisted CDSS could efficiently predict HHC patients.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract The analgesic efficacy and safety of periarticular multimodal drug injection (PMDI) compared with femoral nerve block (FNB) for postoperative pain management in total knee arthroplasty (TKA) ...still remains controversial. We therefore conducted a meta-analysis to quantitatively compare PMDI to FNB in TKA. 10 randomized controlled trials (RCTs) with 744 TKAs in 728 patients were included in this study. The meta-analysis showed that single shot FNB may have better pain relief in the early postoperative period compared with single shot PMDI, and continuous PMDI provided postoperative analgesia comparable to that of continuous FNB. No significant difference was seen in regard to the complications between the two groups. However, due to the variation of the included studies, no firm conclusions can be drawn.
PDF
