Synthesizing antiferromagnets with correlated oxides has been challenging, owing partly to the markedly degraded ferromagnetism of the magnetic layer at nanoscale thicknesses. Here we report on the ...engineering of an antiferromagnetic interlayer exchange coupling (AF-IEC) between ultrathin but ferromagnetic La2/3Ca1/3MnO₃ layers across an insulating CaRu1/2Ti1/2O₃ spacer. The layer-resolved magnetic switching leads to sharp steplike hysteresis loops with magnetization plateaus depending on the repetition number of the stacking bilayers. The magnetization configurations can be switched at moderate fields of hundreds of oersted. Moreover, the AF-IEC can also be realized with an alternative magnetic layer of La2/3Sr1/3MnO₃ that possesses a Curie temperature near room temperature. The findings will add functionalities to devices with correlated-oxide interfaces.
The continuously increasing number and size of lithium-based batteries developed for large-scale applications raise serious environmental concerns. Herein, we address the issues related to ...electrolyte toxicity and safety by proposing a "water-in-ionomer" type of electrolyte which replaces organic solvents by water and expensive and toxic fluorinated lithium salts by a non-fluorinated, inexpensive and non-toxic superabsorbing ionomer, lithium polyacrylate. Interestingly, the electrochemical stability window of this electrolyte is extended greatly, even for high water contents. Particularly, the gel with 50 wt% ionomer exhibits an electrochemical stability window of 2.6 V vs. platinum and a conductivity of 6.5 mS cm
at 20 °C. Structural investigations suggest that the electrolytes locally self-organize and most likely switch local structures with the change of water content, leading to a 50% gel with good conductivity and elastic properties. A LiTi
(PO
)
/LiMn
O
lithium-ion cell incorporating this electrolyte provided an average discharge voltage > 1.5 V and a specific energy of 77 Wh kg
, while for an alternative cell chemistry, i.e., TiO
/LiMn
O
, a further enhanced average output voltage of 2.1 V and an initial specific energy of 124.2 Wh kg
are achieved.
Abstract
A small in-plane external uniaxial pressure has been widely used as an effective method to acquire single domain iron pnictide BaFe
2
As
2
, which exhibits twin-domains without uniaxial ...strain below the tetragonal-to-orthorhombic structural (nematic) transition temperature
T
s
. Although it is generally assumed that such a pressure will not affect the intrinsic electronic/magnetic properties of the system, it is known to enhance the antiferromagnetic (AF) ordering temperature
T
N
( <
T
s
) and create in-plane resistivity anisotropy above
T
s
. Here we use neutron polarization analysis to show that such a strain on BaFe
2
As
2
also induces a static or quasi-static out-of-plane (
c
-axis) AF order and its associated critical spin fluctuations near
T
N
/
T
s
. Therefore, uniaxial pressure necessary to detwin single crystals of BaFe
2
As
2
actually rotates the easy axis of the collinear AF order near
T
N
/
T
s
, and such effects due to spin-orbit coupling must be taken into account to unveil the intrinsic electronic/magnetic properties of the system.
Despite advances in colorectal cancer (CRC) treatment, most advanced CRC patients who experience disease progression after chemotherapy, targeted therapy, and immunotherapy face a situation in which ...there is no available medicine. Thus, new therapeutic drugs for CRC are urgently needed. Studies have shown that cholesteryl ester transfer protein (CETP) has a vital role in tumor development and is a possible target for CRC therapy. We found that Evacetrapib, a CETP inhibitor, suppressed CRC cell growth by inhibiting the Wnt/β-catenin signaling pathway and activating the c-Jun NH2-terminal kinase (JNK) signaling pathway in CRC. Therefore, Evacetrapib displays an anti-cancer effect and is a possible option for treating CRC.
Microalgae are unicellular photosynthetic microorganisms that play a vital role in primary production and have diverse applications in various industries. They have high photosynthetic and metabolic ...capacities and can produce a variety of valuable metabolites, such as lipids, carbohydrates, pigments, and proteins. However, practical applications of microalgae are limited to high-value products due to the high production costs. Algal biotechnology faces challenges such as low energy utilization efficiency and product yield that are currently inadequate to fulfill commercial production. To overcome these challenges, emerging technologies have shown promise to achieve higher production efficiency, including molecular manipulation of photosynthetic efficiency and metabolic activities. Here, we provided an overview of the importance, diversity, and photosynthesis of microalgae, as well as strategies for enhancing their photosynthetic efficiency. We discussed various approaches for improving microalgal photosynthesis, including strain selection and optimization, rational genetic modification, and innovative technologies such as spectral recomposition of light, nanomaterials, advanced cultivation systems, and symbiotic systems. Additionally, we summarized metabolic engineering strategies that focus on optimizing the synthesis of value-added metabolites, such as pigments, long-chain polyunsaturated fatty acids, starch, proteins, and hydrogen in microalgae. By concentrating on improving photosynthetic efficiency and the synthesis of bioactive metabolites, this review provided valuable insights into enhancing microalgae production yields. Overcoming limitations in microalgae production costs can lead to broader applications in various industries. Furthermore, we highlight the potential of these strategies in increasing the efficiency of microalgae as a sustainable source for high-value products.
Diatoms are a major group of unicellular algae that are rich in lipids and carotenoids. However, sustained research efforts are needed to improve the strain performance for high product yields ...towards commercialization. In this study, we generated a number of mutants of the model diatom
, a cosmopolitan species that has also been found in Nordic region, using the chemical mutagens ethyl methanesulfonate (EMS) and
-methyl-
'-nitro-
-nitrosoguanidine (NTG). We found that both chlorophyll
and neutral lipids had a significant correlation with carotenoid content and these correlations were better during exponential growth than in the stationary growth phase. Then, we studied
common metabolic pathways and analyzed correlated enzymatic reactions between fucoxanthin synthesis and pigmentation or lipid metabolism through a genome-scale metabolic model. The integration of the computational results with liquid chromatography-mass spectrometry data revealed key compounds underlying the correlative metabolic pathways. Approximately 1000 strains were screened using fluorescence-based high-throughput method and five mutants selected had 33% or higher total carotenoids than the wild type, in which four strains remained stable in the long term and the top mutant exhibited an increase of 69.3% in fucoxanthin content compared to the wild type. The platform described in this study may be applied to the screening of other high performing diatom strains for industrial applications.
2D magnetic materials with dimerized honeycomb lattices can be treated as mixed‐spin square lattices, in which a quantum phase transition may occur to realize the Bose–Einstein condensation of ...magnons under reachable experimental conditions. However, this has never been successfully realized with integer spin centers. Herein, a spin integer (S = 2) dimerized honeycomb lattice in an iron(II)‐azido compound Fe(4‐etpy)2(N3)2n (FEN, 4‐etpy = 4‐ethylpyridine) is realized. Morphology characterization by transmission electron microscopy, scanning electron microscopy, and atomic force microscopy spectroscopies show that the thinnest place of the sample is ≈13 nm, which is equal to ten layers of the compound. In contrast to the common magnetic properties of long‐range magnetic ordering, Mössbauer and polarized neutron scattering studies reveal that FEN exhibits a reentrant spin glass behavior owing to competing ferro‐ and antiferromagnetic exchange‐coupling interactions within the lattice. Two spin glass phases with disparate canting angles are characterized at 39 and 28 K, respectively. By using Curély's model, two exchange‐coupling constants (J1 = +35.8 cm−1 and J2 = −3.7 cm−1) can be simulated. Moreover, a very large coercive field of ≈1.9 Tesla is observed at 2 K, making FEN a “very hard” van der Waals 2D magnetic material.
A dimerized honeycomb lattice with integer spins is realized in an iron(II)‐azido compound. Morphology characterization shows that the thinnest place of the sample is ≈13 nm, which comprises ten layers of the compound. Magnetic, Mössbauer, and polarized neutron scattering studies reveal a reentrant spin glass behavior, which leads to a “very hard” magnetic hysteresis loop at lower temperatures.
Diatoms, which can accumulate large amounts of carotenoids, are a major group of microalgae and the dominant primary producer in marine environments. Phaeodactylum tricornutum, a model diatom ...species, acquires little silicon for its growth although silicon is known to contribute to gene regulation and play an important role in diatom intracellular metabolism. In this study, we explored the effects of artificial high-silicate medium (i.e. 3.0 mM sodium metasilicate) and LED illumination conditions on the growth rate and pigment accumulation in P. tricornutum, which is the only known species so far that can grow without silicate. It's well known that light-emitting diodes (LEDs) as novel illuminants are emerging to be superior monochromatic light sources for algal cultivation with defined and efficient red and blue lights.
Firstly, we cultivated P. tricornutum in a synthetic medium supplemented with either 0.3 mM or 3.0 mM silicate. The morphology and size of diatom cells were examined: the proportion of the oval and triradiate cells decreased while the fusiform cells increased with more silicate addition in high-silicate medium; the average length of fusiform cells also slightly changed from 14.33 µm in 0.3 mM silicate medium to 12.20 µm in 3.0 mM silicate medium. Then we cultivated P. tricornutum under various intensities of red light in combination with the two different levels of silicate in the medium. Higher biomass productivity also achieved in 3.0 mM silicate medium than in 0.3 mM silicate medium under red LED light irradiation at 128 μmol/m
/s or higher light intensity. Increasing silicate reversed the down-regulation of fucoxanthin and chlorophyll a under high red-light illumination (i.e. 255 μmol/m
/s). When doubling the light intensity, fucoxanthin content decreased under red light but increased under combined red and blue (50:50) lights while chlorophyll a content reduced under both conditions. Fucoxanthin accumulation and biomass productivity increased with enhanced red and blue (50:50) lights.
High-silicate medium and blue light increased biomass and fucoxanthin production in P. tricornutum under high light conditions and this strategy may be beneficial for large-scale production of fucoxanthin in diatoms.
Uncertainty exists regarding the mechanisms by which hypoxia-inducible factors (HIFs) control CD8+T-cell migration into tumor microenvironments. Here, we found that HIF-1α knockdown or overexpression ...resulted in increased or decreased CXCL9, −10, and −11 expression in vitro, respectively. Gene Set Variation Analysis revealed that elevated HIF-1α levels correlated with a poor prognosis, severe pathological stage, and an absence of CD8+ T cells in the tumor microenvironment in colorectal cancer (CRC) patients. HIF-1α was inversely associated with pathways beneficial to anti-tumor immunotherapy and cytokine/chemokine function. In vivo, inhibiting HIF-1α or its upstream regulator BIRC2 significantly suppressed tumor growth and promoted CD8+ T-cell infiltration. CXCR3 neutralizing antibodies reversed these effects, implicating the involvement of CXCL9, −10, and −11/CXCR3 axis. The presence of HIF-1α weakened the upregulation of CXCL9, −10, and −11 by bleomycin and doxorubicin. Combining HIF-1α inhibition with bleomycin promoted CD8+ T-cell infiltration and tumor suppression in vivo. Moreover, doxorubicin could upregulate CXCL9, −10 and −11 by suppressing HIF-1α. Our findings highlight the potential of HIF-1α inhibition to improve CRC microenvironments and increase chemotherapy sensitivity.
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•HIF-1α protein inhibits the expression of CXCL9, −10 and −11 in CRC.•BIRC2 promotes the expression of HIF-1α protein in CRC cell lines.•Knockdown of HIF-1α improves the anti-tumor impact of Bleomycin or Doxorubicin.
The magnetic-field-induced assembly of magnetic nanoparticles (NPs) provides a unique and flexible strategy in the design and fabrication of functional nanostructures and devices. We have ...investigated the field-induced self-assembly of core-shell iron oxide NPs dispersed in toluene by means of small-angle neutron scattering (SANS). The form factor of the core-shell NPs was characterized and analyzed using SANS with polarized neutrons. Large-scale aggregates of iron oxide NPs formed above 0.02 T as indicated by very-small-angle neutron scattering measurements. A three-dimensional long-range ordered superlattice of iron oxide NPs was revealed under the application of a moderate magnetic field. The crystal structure of the superlattice has been identified to be face-centred cubic.
The small-angle neutron scattering patterns show that iron oxide nanoparticles assemble into highly ordered three-dimensional aggregates in solution by applying external magnetic fields above 0.1 T.
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