To balance the utilization of rare earth (RE) resource and develop Ce-based permanent magnets with high performance/cost ratio, the role of La substitution in the melt-spun (Ce
1−
x
La
x
)
y
Fe
14
B ...(
x
= 0–0.4, and 0.5;
y
= 2–4) alloys has been investigated. It has been confirmed that the hard magnetic properties of Ce-based magnets can be effectively enhanced by partial substitution of La. The maximum (
BH
)
max
of (Ce,La)–Fe–B alloys can be obtained at a Ce:La atomic ratio of 7:3. The lattice parameters and Curie temperature of the hard magnetic (Ce/La)
2
Fe
14
B phase increase linearly with increasing La content. Three different alloy systems with
y
= 2, 2.5 and 3 show similar behavior of magnetic properties dependences on La. In the RE-rich compositions, La substitution for Ce can effectively inhibit the precipitation of the CeFe
2
phase. A solid solution, Ce(La) phase with a space group of Fm-3m, appears in the (Ce
0.7
La
0.3
)
y
Fe
14
B alloys with
y
≥ 3.5. A good combination of magnetic properties with
H
cj
= 345 kA/m,
J
5T
= 1.03 T,
J
r
= 0.60 T, and (
BH
)
max
= 6.3 MGOe is obtained in (Ce
0.7
La
0.3
)
2.5
Fe
14
B alloy. In addition, 30 at.% La substitution for Ce can significantly refine the grains, resulting in the enhancement of exchange coupling interaction. The present finding is beneficial for designing new and low-cost magnetic materials.
We perform time- and angle-resolved photoemission spectroscopy (trARPES) on optimally doped Bi2Sr2CaCu2O8+δ (BSCCO-2212) using sufficient energy resolution (9 meV) to resolve the k -dependent ...near-nodal gap structure on time scales where the concept of an electronic pseudotemperature is a useful quantity, i.e., after electronic thermalization has occurred. We study the ultrafast evolution of this gap structure, uncovering a very rich landscape of decay rates as a function of angle, temperature, and energy. We explicitly focus on the quasiparticle states at the gap edge as well as on the spectral weight inside the gap that “fills” the gap—understood as an interaction, or self-energy effect—and we also make high resolution measurements of the nodal states, enabling a direct and accurate measurement of the electronic temperature (or pseudotemperature) of the electrons in the system. Rather than the standard method of interpreting these results using individual quasiparticle scattering rates that vary significantly as a function of angle, temperature, and energy, we show that the entire landscape of relaxations can be understood by modeling the system as following a nonequilibrium, electronic pseudotemperature that controls all electrons in the zone. Furthermore, this model has zero free parameters, as we obtain the crucial information of the SC gap Δ and the gap-filling strength ΓTDoS by connecting to static ARPES measurements. The quantitative and qualitative agreement between data and model suggests that the critical parameters and interactions of the system, including the pairing interactions, follow parametrically from the electronic pseudotemperature. We expect that this concept will be relevant for understanding the ultrafast response of a great variety of electronic materials, even though the electronic pseudotemperature may not be directly measurable.
Incretin therapies such as glucagon-like peptide 1 (GLP-1) agonists are commonly used for the treatment of type 2 diabetes mellitus. GLP-1 mimetics, besides improving glycemic control, have been ...shown to influence multiple pathways regulating blood pressure (BP). We investigated the GLP-1 analogs effects on BP from published randomized studies using a meta-analytic approach.
Thirty-three trials (12,469 patients) that assessed the efficacy of GLP-1 analogs on glycemic control (HbA1C) over 12-56 weeks that met additional criteria, including the availability of standardized sitting BP assessment and weight parameters, were identified. Comparator therapy included oral antiglycemic drugs or placebo. The weighted mean difference (WMD) in systolic BP (SBP) change was calculated using a random-effects model after performing a test for heterogeneity.
Forty-one percent of patients were treated with liraglutide (0.3-3mg once daily), whereas 59% were treated with exenatide (5-10 µg twice daily or 2mg weekly). GLP-1 treatment achieved a greater SBP reduction than comparator therapy (WMD = 2.22mm Hg; 95% confidence interval (CI) = -2.97 to -1.47). In the pooled analysis, GLP-1 had beneficial effects on weight loss (WMD = -2.56kg; 95% CI = -3.12 to -2.00), HbA1c reduction (WMD = -0.41%; 95% CI = -0.78 to -0.04) but was associated with a heart rate increase (WMD = 1.30 bpm; 95% CI = 0.26-2.33). In a separate meta-regression analysis, the degree of SBP change was not related to baseline BP, weight loss, or improvement in HbA1C.
This meta-analysis provides evidence that GLP-1 analogs reduce sitting SBP. These findings may support potentially favorable long-term cardiovascular outcomes.
Recent studies have found that the core-shell structured metal nanoparticles and porous carbon nanofibers (PCNF) are combined into a microwave absorbing material through electrospinning, which ...exhibits excellent microwave absorption performance. In this study, the core-shell structure Co nanoparticles prepared by the self-developed HEIBE process (production rate of > 50 g/h) were combined with porous carbon fibers, and their absorbing properties were greatly improved. The morphology of Co/PCNF demonstrated that CoNPs are randomly dispersed in the porous carbon nanofibers and carbon nanofiber form complex conductive network which enhances the dielectric loss of the materials. Meanwhile, the Co/PCNF has a low graphitization and shows a significant improvement in permittivity due to the combination of CoNPs and high conductivity of carbon material. The maximum reflection loss (RL) of Co/PCNF reaches - 63.69 dB at 5.28 GHz with a thickness of 5.21 mm and the absorption bandwidth (RL ≤ - 10.0 dB) is 12.92 GHz. In terms of 5.60 mm and 6.61 mm absorber, there are two absorption peaks of - 47.64 dB and - 48.30 dB appear around 12.50 GHz and 14.10 GHz, respectively. The results presented in this paper may pave a way for promising applications of lightweight and high-efficiency microwave absorbing materials (MAMs).
A novel method to combine hot pressing and grain boundary diffusion in order to fabricate La(Fe,Si)13 based magnetocaloric composites is described. LaFe11.6Si1.4/La-Co magnetocaloric composites were ...prepared by hot-pressing, followed by diffusion annealing heat treatment. The Curie temperature (TC) of these composites increases from 197 K to ∼235 K due to the diffusion of Co into the NaZn13–type (1:13) majority phase. The maximum magnetic entropy change (–ΔSM)max at 2 T first increases with increasing diffusion time from 5.62 to 7.60 J/(kgˑK) and followed by a further increase up to 9.15 J/(kgˑK) due to the recombination of the 1:13 phase. The Co content of the La-Co binder could be used to tune the formation of the desired 1:13 phase.
•LaFe11.6Si1.4/La-Co composites were prepared by hot-pressing followed by diffusion annealing.•The diffusion of Co into the NaZn13–type majority phase can improve the TC of these composites.•Improvement in the MCE of these composites is due to the recombination of 1:13 phase.•HP and GBD can be used in mass production of high performance La(Fe,Si)13 based MCMs.
Summary
Background
The short‐term effect of ambient air pollution on atopic dermatitis (AD), along with its effect modifiers, has not been fully addressed.
Objectives
To examine the short‐term ...associations between air pollution and AD, and to identify effect modifications by age and season.
Methods
We used the generalized additive model to evaluate the short‐term effect of ambient air pollution on daily hospital visits for AD, adjusting for potential confounders. Subgroup analyses were performed to identify potential effect modifications by season and age (< 18 years and ≥ 18 years).
Results
A total of 29 972 hospital visits for AD were recorded in Guangzhou, China, from 19 January 2013 to 31 December 2017. Among them, 72·8% were visits by children and 51·4% occurred in the cool season. Acute and delayed effects on AD hospital visits were significant for all air pollutants. Stronger effects were seen in the cool season (approximately 1·7–3·0 times higher than effects in the warm season). Stronger effects were also observed in children (approximately 1·3–1·8 times higher than effects in adults). Sensitivity analyses indicated the results were robust.
Conclusions
Air pollution might be an important trigger for AD in subtropical Guangzhou, China. Children are more vulnerable than adults, and the effects are stronger in the cool season.
What is already known about this topic?
Atopic dermatitis (AD) has the highest number of disability‐adjusted life‐years among skin disorders.
The acute effect of air pollution on AD has not been well studied in China.
What does this study add?
We found that air pollution (including ambient fine particulate matter, inhalable particles, sulfur dioxide, nitrogen dioxide and ozone) acutely triggers AD, and that children are more sensitive to this effect.
The cool season is the vulnerable exposure window for these acute effects.
The structure and magnetic properties of LaFe
11.6
Si
1.4
/Ce
40
Co
60
bulk composites prepared by hot pressing sintering (HPS), followed by high-temperature diffusion annealing, were investigated. ...During the HPS process, the La(Fe,Si)
13
alloy powder particles combined with Ce
40
Co
60
binder and a porous structure with high mechanical strength were obtained. The addition of Ce
40
Co
60
can also promote the peritectic reaction. Annealing has important effects on the magnetocaloric properties due to the diffusion of Ce and Co into the La(Fe,Si)
13
phase during annealing. HPS samples were annealed at 1373 K for 24 h, and a table-like magnetocaloric effect, exhibiting a constant high magnetic entropy change (− ∆
S
M
) of ~ 4.0 J/(kg K) in a commercially useful temperature region of 28 K (236–264 K), was obtained for a field change of 2 T. The values of full width at half maximum of (− ∆
S
M
)–
T
plots (Δ
T
FWHM
) and enhanced refrigeration capacity for the composites are 55 K and 173 J/kg, respectively, for a field change of 2 T. The composites exhibit high compressive strength of up to 312 MPa. The present results indicate that LaFe
11.6
Si
1.4
/Ce
40
Co
60
bulk composites can meet the requirement of near room temperature magnetic refrigeration based on the Ericsson cycle.
We report a fine tuned doping study of strongly overdoped Bi2Sr2CaCu2O8+ delta single crystals using electronic Raman scattering. Combined with theoretical calculations, we show that the doping, at ...which the normal-state pseudogap closes, coincides with a Lifshitz quantum phase transition where the active holelike Fermi surface becomes electronlike. This conclusion suggests that the microscopic cause of the pseudogap is sensitive to the Fermi surface topology. Furthermore, we find that the superconducting transition temperature is unaffected by this transition, demonstrating that their origins are different on the overdoped side.
Catheter-based intra-arterial drug therapies have proven effective for a range of oncologic, neurologic, and cardiovascular applications. However, these procedures are limited by their invasiveness ...and relatively broad drug spatial distribution. The ideal technique for local pharmacotherapy would be noninvasive and would flexibly deliver a given drug to any region of the body with high spatial and temporal precision. Combining polymeric perfluorocarbon nanoemulsions with existent clinical focused ultrasound systems could in principle meet these needs, but it has not been clear whether these nanoparticles could provide the necessary drug loading, stability, and generalizability across a range of drugs, beyond a few niche applications. Here, we develop polymeric perfluorocarbon nanoemulsions into a generalized platform for ultrasound-targeted delivery of hydrophobic drugs with high potential for clinical translation. We demonstrate that a wide variety of drugs may be effectively uncaged with ultrasound using these nanoparticles, with drug loading increasing with hydrophobicity. We also set the stage for clinical translation by delineating production protocols that are scalable and yield sterile, stable, and optimized ultrasound-activated drug-loaded nanoemulsions. Finally, we exhibit a new potential application of these nanoemulsions for local control of vascular tone. This work establishes the power of polymeric perfluorocarbon nanoemulsions as a clinically-translatable platform for efficacious, noninvasive, and localized ultrasonic drug uncaging for myriad targets in the brain and body.
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