Abstract
Combustion is a complex chemical system which involves thousands of chemical reactions and generates hundreds of molecular species and radicals during the process. In this work, a neural ...network-based molecular dynamics (MD) simulation is carried out to simulate the benchmark combustion of methane. During MD simulation, detailed reaction processes leading to the creation of specific molecular species including various intermediate radicals and the products are intimately revealed and characterized. Overall, a total of 798 different chemical reactions were recorded and some new chemical reaction pathways were discovered. We believe that the present work heralds the dawn of a new era in which neural network-based reactive MD simulation can be practically applied to simulating important complex reaction systems at ab initio level, which provides atomic-level understanding of chemical reaction processes as well as discovery of new reaction pathways at an unprecedented level of detail beyond what laboratory experiments could accomplish.
Leptomeningeal metastases (LM) are more frequent in non-small-cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations. Due to limited access to leptomeningeal lesions, the ...purpose of this study was to explore the potential role of cerebrospinal fluid (CSF) as a source of liquid biopsy in patients with LM.
Primary tumor, CSF, and plasma in NSCLC with LM were tested by next-generation sequencing. In total, 45 patients with suspected LM underwent lumbar puncture, and those with EGFR mutations diagnosed with LM were enrolled.
A total of 28 patients were enrolled in this cohort; CSF and plasma were available in 26 patients, respectively. Driver genes were detected in 100% (26/26), 84.6% (22/26), and 73.1% (19/26) of samples comprising CSF cell-free DNA (cfDNA), CSF precipitates, and plasma, respectively; 92.3% (24/26) of patients had much higher allele fractions in CSF cfDNA than the other two media. Unique genetic profiles were captured in CSF cfDNA compared with those in plasma and primary tissue. Multiple copy number variations (CNVs) were mainly identified in CSF cfDNA, and MET copy number gain identified in 47.8% (11/23) of patients was the most frequent one, while other CNVs included ERBB2, KRAS, ALK, and MYC. Moreover, loss of heterozygosity (LOH) of TP53 was identified in 73.1% (19/26) CSF cfDNA, which was much higher than that in plasma (2/26, 7.7%; P<0.001). There was a trend towards a higher frequency of concomitant resistance mutations in patients with TP53 LOH than those without (70.6% versus 33.3%; P=0.162). EGFR T790M was identified in CSF cfDNA of 30.4% (7/23) of patients who experienced TKI progression.
CSF cfDNA could reveal the unique genetic profiles of LM and should be considered as the most representative liquid biopsy medium for LM in EGFR-mutant NSCLC.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Highlights ► Suppressive and therapeutic VPA application attenuated EAE. ► VPA suppressed inflammatory mediators in EAE spinal cords. ► VPA altered cytokine profile from Th1 and Th17 to Th2 and ...regulatory T cells in lymph nodes. ► VPA inhibited non-specific lymphocyte proliferation.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
24.
General relationship between strength and hardness Zhang, P.; Li, S.X.; Zhang, Z.F.
Materials science & engineering. A, Structural materials : properties, microstructure and processing,
11/2011, Volume:
529
Journal Article
Peer reviewed
► The hardness is not an intrinsic property but reflects the hardening state in CG. ► The ratio of hardness to strength can also be reflected by indentation morphology. ► The ratio of hardness to ...strength increases with increasing parameter
α. ►
H
V
=
3
σ
UTS
is valid for materials with relatively high strength and better toughness.
Both hardness and strength are the important properties of materials, and they often obey the three times empirical relationship in work-hardened metals and some bulk metallic glasses (BMGs). But the relationships between strength and hardness are quite different for those coarse-grained (CG) and ultrafine-grained materials, brittle BMGs and ceramics. In the present work, some Cu alloys with different microstructures, Zr-, Co-based BMGs and Al
2O
3 were employed to analyze the general relationship between hardness and strength. Several different relationships could be gotten from the experimental results of different materials available, and three types of indentation morphologies were observed. Indentation with “sink-in” morphology always represents a state of material and one third of hardness is in the range from yield strength to ultimate tensile strength. The other two indentation morphologies induced the fully hardening of material, so hardness could represent the intrinsic mechanical property of materials. The ratios of hardness to strength are found to be affected by the piled-up behaviors and their ability of shear deformation. Combined effect of the two aspects makes hardness approximately be three times of strength in the work-hardened crystalline materials and the shearable BMGs, but higher than three times of strength in the brittle-, annealed BMGs and ceramics.
Full text
Available for:
GEOZS, IMTLJ, KISLJ, NUK, OILJ, PNG, SAZU, SBJE, UL, UM, UPCLJ, UPUK
This study investigated the effect of prepartum diets differing in energy density on growth performance, immunity, and antioxidation capability of neonatal calves. Thirty Holstein dairy cows were ...allocated at random into 3 groups: low energy group L; net energy of lactation (NEL)=5.25MJ/kg of dry matter (DM); medium energy group (M; NEL=5.88MJ/kg of DM); and high energy group (H; NEL=6.48MJ/kg of DM) at d 21 prepartum. Plasma was sampled for analysis of glucose, total protein, β-hydroxybutyrate, and nonesterified fatty acids at 21, 14, and 7 d before parturition. After calving, birth weight and measurements of the calves in each group were recorded, and blood samples were collected for analysis of CD4, CD8, CD21, IL-2, IL-4, IL-6, total antioxidant capacity, superoxide dismutase, glutathione peroxidase, and maleic dialdehyde. The results indicated that although maternal weight did not differ among L, M, and H groups at 21, 14, and 7 d before parturition, the concentrations of glucose and β-hydroxybutyrate at 14 and 7 d in the L group were decreased compared with that in the H group. In addition, nonesterified fatty acids concentrations increased significantly in the L group at 14 and 7 d before parturition compared with that in the M and H groups. Birth weight, body height, body length, abdominal circumference, thoracic girth, umbilical girth, and levels of CD4, CD4:CD8, IL-2, IL-4, total antioxidant capacity, and superoxide dismutase were decreased in calves of the L group compared with those of the H group. For the M group, CD4, CD4:CD8, and superoxide dismutase were decreased; and in the L group glutathione peroxidase and maleic dialdehyde levels were significantly increased compared with those of the H group. Reducing the maternal energy density during the last 21 d before parturition had a negative effect on growth and development, immunity, and antioxidation capability of neonatal calves.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The morphological disparity of lophotrochozoan phyla makes it difficult to predict the morphology of the last common ancestor. Only fossils of stem groups can help discover the morphological ...transitions that occurred along the roots of these phyla. Here, we describe a tubular fossil Yuganotheca elegans gen. et sp. nov. from the Cambrian (Stage 3) Chengjiang Lagerstätte (Yunnan, China) that exhibits an unusual combination of phoronid, brachiopod and tommotiid (Cambrian problematica) characters, notably a pair of agglutinated valves, enclosing a horseshoe-shaped lophophore, supported by a lower bipartite tubular attachment structure with a long pedicle with coelomic space. The terminal bulb of the pedicle provided anchorage in soft sediment. The discovery has important implications for the early evolution of lophotrochozoans, suggesting rooting of brachiopods into the sessile lophotrochozoans and the origination of their bivalved bauplan preceding the biomineralization of shell valves in crown brachiopods.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Non-Hermitian systems distinguish themselves from Hermitian systems by exhibiting a phase transition point called an exceptional point (EP), at which two eigenstates coalesce under a system parameter ...variation. Many interesting EP phenomena, such as level crossings in nuclear and condensed matter physics, and unusual phenomena in optics, such as loss-induced lasing and unidirectional transmission, can be understood by considering a simple 2×2 non-Hermitian matrix. At a higher dimension, more complex EP physics not found in two-state systems arises. We consider the emergence and interaction of multiple EPs in a four-state system theoretically and realize the system experimentally using four coupled acoustic cavities with asymmetric losses. We find that multiple EPs can emerge, and as the system parameters vary, these EPs can collide and merge, leading to higher-order singularities and topological characteristics much richer than those seen in two-state systems. The new physics obtained is not limited to the acoustic systems demonstrated here. It also applies to other systems as well, such as coupled photonic cavities and waveguides.
Full text
Available for:
CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM, UPUK
The mechanical properties and tensile deformation mechanism of Ti-6.5Al-3.5Mo-1.5Zr-0.25Si alloy (TC11) with different percentages of primary α phase (αp) were studied by conventional and interrupted ...tensile tests, respectively. The results show that the strength of TC11 alloy increases with the increase of the percentage of αp. During tensile deformation, TC11 alloy with different percentages of αp exhibits similar behavior. The deformation mechanism in αp transforms from single slip to multiple slip. While, the microcracks first initiate at the interface of two phases, propagate along it, and then propagate through the transformed β phase (βt) and finally through αp. Finally, a method for predicting the strength of TC11 alloy considering the sizes of αp and βt is proposed.
Full text
Available for:
GEOZS, IMTLJ, KISLJ, NUK, OILJ, PNG, SAZU, SBJE, UL, UM, UPCLJ, UPUK
30.
Improving the fatigue strength of 7075 alloy through aging Leng, L.; Zhang, Z.J.; Duan, Q.Q. ...
Materials science & engineering. A, Structural materials : properties, microstructure and processing,
12/2018, Volume:
738
Journal Article
Peer reviewed
In order to optimize the fatigue strength of 7075 Al alloy, the hardness, tensile and fatigue tests as well as the microstructure observation under different aging conditions were investigated. The ...result indicates that, with the aging time increasing, the precipitation spacing first decreases and then increases, which leads to the hardness and tensile strength first increasing and then decreasing. With the increase of yield strength, the fatigue strength increases first and then decreases, resulting in an optimization of fatigue strength. Especially, the specimen aged at 120 °C for 48 h with strength and elongation in middle of the three specimens exhibits the highest fatigue strength of 165 MPa. Considering the effect of yield strength on fatigue strength and fatigue damage, the causes for the parabolic variation of fatigue strength were analyzed.
Full text
Available for:
GEOZS, IMTLJ, KISLJ, NUK, OILJ, PNG, SAZU, SBJE, UL, UM, UPCLJ, UPUK
PDF
