Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
LanguageLanguage
-
SubjectSubject
-
Item TypeItem Type
-
DisciplineDiscipline
-
YearFrom:-To:
-
More FiltersMore FiltersIs Peer Reviewed
Done
Filters
Reset
16,923
result(s) for
"Liu, B. J"
Sort by:
Integration of full divertor detachment with improved core confinement for tokamak fusion plasmas
2021
Divertor detachment offers a promising solution to the challenge of plasma-wall interactions for steady-state operation of fusion reactors. Here, we demonstrate the excellent compatibility of actively controlled full divertor detachment with a high-performance (
β
N
~ 3,
H
98
~ 1.5) core plasma, using high-β
p
(poloidal beta,
β
p
> 2) scenario characterized by a sustained core internal transport barrier (ITB) and a modest edge transport barrier (ETB) in DIII-D tokamak. The high-
β
p
high-confinement scenario facilitates divertor detachment which, in turn, promotes the development of an even stronger ITB at large radius with a weaker ETB. This self-organized synergy between ITB and ETB, leads to a net gain in energy confinement, in contrast to the net confinement loss caused by divertor detachment in standard H-modes. These results show the potential of integrating excellent core plasma performance with an efficient divertor solution, an essential step towards steady-state operation of reactor-grade plasmas.
Plasma fusion devices like tokamaks are important for energy generation but there are many challenges for their steady state operation. Here, the authors show that full divertor detachment is compatible with high-confinement high-poloidal-beta core plasmas and this prevents the damage to the divertor target plates and the first wall.
Journal Article
Macroscopic waves, biological clocks and morphogenesis driven by light in a giant unicellular green alga
by
Afik, Eldad
,
Liu, Toni J. B.
,
Meyerowitz, Elliot M.
in
631/136/1660
,
639/766/530/2803
,
639/766/747
2023
A hallmark of self-organisation in living systems is their capacity to stabilise their own dynamics, often appearing to anticipate and act upon potential outcomes.
Caulerpa brachypus
is a marine green alga consisting of differentiated organs resembling leaves, stems and roots. While an individual can exceed a metre in size, it is a single multinucleated giant cell. Thus
Caulerpa
presents the mystery of morphogenesis on macroscopic scales in the absence of cellularization. The experiments reported here reveal self-organised waves of greenness — chloroplasts — that propagate throughout the alga in anticipation of the day-night light cycle. Using dynamical systems analysis we show that these waves are coupled to a self-sustained oscillator, and demonstrate their entrainment to light. Under constant conditions light intensity affects the natural period and drives transition to temporal disorder. Moreover, we find distinct morphologies depending on light temporal patterns, suggesting waves of chlorophyll could link biological oscillators to metabolism and morphogenesis in this giant single-celled organism.
Self-organised waves propagate throughout the alga
Caulerpa
. Light temporal patterns control the waves and algal morphology, potentially tying light-synchronized self-oscillations to one of the mysteries of single-cell development, morphogenesis.
Journal Article
Scale law of complex deformation transitions of nanotwins in stainless steel
2019
Understanding the deformation behavior of metallic materials containing nanotwins (NTs), which can enhance both strength and ductility, is useful for tailoring microstructures at the micro- and nano- scale to enhance mechanical properties. Here, we construct a clear deformation pattern of NTs in austenitic stainless steel by combining in situ tensile tests with a dislocation-based theoretical model and molecular dynamics simulations. Deformation NTs are observed in situ using a transmission electron microscope in different sample regions containing NTs with twin-lamella-spacing (
λ
) varying from a few nanometers to hundreds of nanometers. Two deformation transitions are found experimentally: from coactivated twinning/detwinning (
λ
< 5 nm) to secondary twinning (5 nm <
λ
< 129 nm), and then to the dislocation glide (
λ
> 129 nm). The simulation results are highly consistent with the observed strong
λ
-effect, and reveal the intrinsic transition mechanisms induced by partial dislocation slip.
The deformation mechanisms of twin boundaries in nanotwinned metallic materials are still unclear. Here the authors combine in situ transmission electron microscopy tensile tests and molecular dynamics simulations with a dislocation-based theoretical model to reveal the deformation mechanism of nanotwins.
Journal Article
Effects of stale maize on growth performance, immunity, intestinal morphology and antioxidant capacity in broilers
2020
ObjectiveThis study was conducted to determine the effects of stale maize on growth performance, immunity, intestinal morphology, and antioxidant capacity in broilers.MethodsA total of 800 one-day-old male Arbor Acres broilers (45.4±0.5 g) were blocked based on body weight, and then allocated randomly to 2 treatments with 20 cages per treatment and 20 broilers per cage in this 6-week experiment. Dietary treatments included a basal diet and diets with 100% of control maize replaced by stale maize.ResultsThe content of fat acidity value was higher (p<0.05) while the starch, activities of catalase and peroxidase were lower (p<0.05) than the control maize. Feeding stale maize diets reduced (p<0.05) average daily feed intake (ADFI) throughout the experiment, feed conversion ratio (FCR) during d 0 to 21 and the whole experiment as well as relative weight of liver, spleen, bursa of Fabricius and thymus (p<0.05) on d 21. Feeding stale maize diets decreased jejunum villus height (VH) and VH/crypt depth (CD) (p<0.05) on d 21 and 42 as well as ileum VH/CD on d 42. The levels of immunoglobulin G, acid α-naphthylacetate esterase positive ratios and lymphocyte proliferation on d 21 and 42 as well as lysozyme activity and avian influenza antibody H5N1 titer on d 21 decreased (p<0.05) by the stale maize. Feeding stale maize diets reduced (p<0.05) serum interferon-γ, tumor necrosis factor-α, interleukin-2 on d 21 and interleukin-6 on d 21 and 42. Broilers fed stale maize diets had lower levels of (p<0.05) total antioxidative capacity on d 42, superoxide dismutase and glutathione peroxidase on d 21 and 42, but higher (p<0.05) levels of malondialdehyde on d 21 and 42.ConclusionFeeding 100% stale maize decreased ADFI and FCR, caused adverse effects on immunity and antioxidant function and altered intestinal morphology in broilers.
Journal Article
Effects of absorbents on growth performance, blood profiles and liver gene expression in broilers fed diets naturally contaminated with aflatoxin
2020
ObjectiveThe study was conducted to evaluate the effects of the absorbent (a mixture of activated carbon and hydrated sodium calcium aluminosilicate) on growth performance, blood profiles and hepatic genes expression in broilers fed diets naturally contaminated with aflatoxin.MethodsA total of 1,200 one-day-old male chicks were randomly assigned to 6 treatments with 10 replicate cages per treatment. The dietary treatments were as follows: i) control (basal diets); ii) 50% contaminated corn; iii) 100% contaminated corn; iv) control+1% adsorbent; v) 50% contaminated corn+1% absorbent; vi) 100% contaminated corn+1% absorbent.ResultsDuring d 1 to 21, feeding contaminated diets reduced (p<0.05) body weight (BW), average daily gain (ADG), and average daily feed intake (ADFI), but increased (p<0.05) feed-to-gain ratio (F/G). The absorbent supplementation increased (p<0.05) BW, ADG, and ADFI. There were interactions (p<0.05) in BW, ADG, and ADFI between contaminated corn and absorbent. Overall, birds fed 100% contaminated diets had lower (p<0.05) final BW and ADG, but higher (p<0.05) F/G compared to those fed control diets. The absorbent addition increased (p<0.05) serum albumin concentration on d 14 and 28 and total protein (TP) level on d 28, decreased (p<0.05) alanine transaminase activity on d 14 and activities of aspartate aminotransferase and alkaline phosphatase on d 28. Feeding contaminated diets reduced (p<0.05) hepatic TP content on d 28 and 42. The contaminated diets upregulated (p<0.05) expression of interleukin-6, catalase (CAT), and superoxide dismutase (SOD), but downregulated (p<0.05) glutathione S-transferase (GST) expression in liver. The absorbent supplementation increased (p<0.05) interleukin-1β, CAT, SOD, cytochrome P450 1A1 and GST expression in liver. There were interactions (p<0.05) in the expression of hepatic CAT, SOD, and GST between contaminated corn and absorbent.ConclusionThe results suggest that the naturally aflatoxin-contaminated corn depressed growth performance, while the adsorbent could partially attenuate the adverse effects of aflatoxin on growth performance, blood profiles and hepatic genes expression in broilers.
Journal Article
Comparison of laparoscopic hernia repair and open herniotomy in children: a retrospective cohort study
2017
Background
Laparoscopic hernia repair in infancy and childhood is still debatable. The objective of this study is to compare laparoscopic-assisted hernia repair (LH) versus open herniotomy (OH) as regards operative time, postoperative complications, recurrence rate, and contralateral metachronous hernia rate.
Methods
We analyzed all the patients with inguinal hernia who underwent surgery in our hospital from January 1, 2015 to December 31, 2015. There were 1125 patients, of which 202 patients received laparoscopic inguinal hernia repair (group A) and 923 patients received open herniotomy (group B). We recalled all the patients’ records to identify operative time, postoperative hydrocele formation, and contralateral patent processus vaginalis (CPP) detection; we recalled all the patients’ parents to identify the ipsilateral and contralateral recurrence and the testis position.
Results
During the study period, the lost to follow-up rate is 9.9% in group A and 14.1% in group B. The mean follow-up period was about 10.1 months. The mean operative time for females with bilateral hernia in group A was much shorter than that for those in group B (
P
= 0.001). The postoperative hydrocele formation rate in group A was 1.5%, compared with 8.2% in group B (
P
= 0.001). The recurrence rate was 0.64% in group A, whereas in group B the recurrence rate was 0.46%. Of patients with unilateral hernia, none in group A experienced a contralateral metachronous hernia (MH) compared with 10.1% in group B (
P
< 0.001) and 65% MH appeared in 3 months after the first hernia repair. Females and patients with initial left-sided hernia tended to have a contralateral MH after the first open hernia repair.
Conclusion
Laparoscopic hernia repair in children is safe and effective, especially for female patients and patients with initial left-sided hernia. We recommend repairing the CPP simultaneously when performing laparoscopic procedures.
Journal Article
Design of Combined Buffer on a High-precision Weapon
2023
Taking the buffer of a high-precision sniper weapon as the research object, according to its technical and tactical performance and buffer requirements, this article focuses on the design of the grooved variable hydraulic damper and anti-forward spring buffer by adopting hydraulic spring combination buffer technology. Using MATLAB mathematical simulation software, the recoil force model was constructed, and the simulation calculation was performed. In the light of calculation results, on the basis of modifying and improving the design parameters of the buffer, the actual shooting test of the buffer has been carried out. The test results show that the buffer can effectively reduce the peak value of recoil resistance while ensuring the shooting accuracy of sniper weapons, thereby reflecting the design of the buffer has achieved the expected effect. The test results verify the principle of the combined buffer, which provides certain reference significance for the design of other large-caliber sniper weapons.
Journal Article
Geospace magnetic field responses to interplanetary shocks
by
Liu, J. B.
,
Li, H.
,
Kan, J. R.
in
Earth sciences
,
Earth, ocean, space
,
Exact sciences and technology
2009
We perform a statistical survey of geospace magnetic field responses, including the geosynchronous magnetic field and the sudden impulses on the ground, to interplanetary shocks (IP shocks) between 1998 and 2005. The magnitude of the geosynchronous magnetic field (dBz) responses to IP shocks depends strongly on local time, which peaks near the noon meridian; however, the relative magnitude of the responses depends only weakly on local time. These results are similar to those obtained from the statical study of the responses to solar wind dynamic pressure pulses. However, negative responses (where dBz is negative) were sometimes observed in the nightside of the magnetosphere even though the IP shocks always caused increases in the solar wind dynamic pressure, a new phenomenon not widely reported in the literature. Our analysis shows that ∼75% of negative responses in the midnight sector are associated with southward interplanetary magnetic field. For a moderately compressed magnetosphere, the amplitude of the geosynchronous response dBz could be determined by the average value of the background local magnetic field. As the magnitude of the upstream solar wind dynamic pressure increases, the rate of response increases correspondingly. The dBz at the geosynchronous orbit near local noon and the amplitude of sudden impulses (dSYM‐H) on the ground are highly correlated.
Journal Article
Epigallocatechin-3-gallate local pre-exposure application prevents SHIV rectal infection of macaques
2018
Epigallocatechin-3-gallate (EGCG), a natural and major ingredient of green tea, has been shown to have anti-inflammation and anti-HIV-1 properties. We demonstrated that the intrarectal administration of EGCG could protect rhesus macaques from repetitive, intrarectal challenges with low-dose SHIVSF162P3N. This protection has a per-exposure risk reduction of 91.5% (P = 0.0009; log-rank test) and a complete protection of 87.5% (P < 0.001; Fisher's exact test). All protected animals showed no evidence of systemic and mucosal SHIV infection as demonstrated by the absence of viral RNA, DNA and antibodies. In contrast, all controls became infected after repeated SHIV challenges (a median of 2.5 times, range of 1–8 times). Mechanistically, EGCG could block the binding of HIV-1 gp120 to CD4 receptor and suppress the macrophage infiltration/activation in the rectal mucosa of macaques. These data support further clinical evaluation and development of EGCG as a novel, safe and cost-effective microbicide for preventing sexual transmission of HIV-1.
Journal Article
Atomistic Simulations to Predict Favored Glass-Formation Composition and Ion-Beam-Mixing of Nano-Multiple-Metal-Layers to Produce Ternary Amorphous Films
2018
Based on the framework of long-range empirical formulas, the interatomic potentials were constructed for the Ni-Nb-Mo (fcc-bcc-bcc) and Ni-Zr-Mo (fcc-hcp-bcc) ternary metal systems. Applying the constructed potentials, atomistic simulations were performed to predict the energetically favored glass formation regions (GFRs) in the respective composition triangles of the systems. In addition, the amorphization driving forces (ADFs), i.e., the energy differences between the solid solutions and disordered phases, were computed and appeared to correlate with the so-called glass forming abilities. To verify the atomistic prediction, ion beam mixing with nano-multiple-metal-layers was carried out to produce ternary amorphous films. The results showed that the composition of ternary amorphous films obtained by ion beam mixing all locate inside the GFRs, supporting the predictions of atomistic simulations. Interestingly, the minimum ion dosage required for amorphization showed a negative correlation with the calculated ADF, implying that the predicted amorphization driving force could be an indicator of the glass formation ability.
Journal Article