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1.
Biomed Pharmacother ; 173: 116427, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38484558

RESUMO

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.


Assuntos
Neoplasias Colorretais , Resistencia a Medicamentos Antineoplásicos , Subunidade alfa do Fator 1 Induzível por Hipóxia , Humanos , Bleomicina , Linfócitos T CD8-Positivos , Linhagem Celular Tumoral , Quimiocina CXCL9/genética , Quimiocina CXCL9/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/metabolismo , Citocinas , Doxorrubicina/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Microambiente Tumoral
2.
Nanoscale ; 16(3): 1291-1303, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38131194

RESUMO

The magnetic properties of spinel nanoparticles can be controlled by synthesizing particles of a specific shape and size. The synthesized nanorods, nanodots and cubic nanoparticles have different crystal planes selectively exposed on the surface. The surface effects on the static magnetic properties are well documented, while their influence on spin waves dispersion is still being debated. Our ability to manipulate spin waves using surface and defect engineering in magnetic nanoparticles is the key to designing magnonic devices. We synthesized cubic and spherical nanoparticles of a classical antiferromagnetic material Co3O4 to study the shape and size effects on their static and dynamic magnetic proprieties. Using a combination of experimental methods, we probed the magnetic and crystal structures of our samples and directly measured spin wave dispersions using inelastic neutron scattering. We found a weak, but unquestionable, increase in exchange interactions for the cubic nanoparticles as compared to spherical nanoparticle and bulk powder reference samples. Interestingly, the exchange interactions in spherical nanoparticles have bulk-like properties, despite a ferromagnetic contribution from canted surface spins.

3.
Acta Crystallogr B Struct Sci Cryst Eng Mater ; 79(Pt 6): 473-481, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37820014

RESUMO

The magnetic structure of chromium arsenide CrAs is studied with neutron powder diffraction at ambient pressure in the temperature range 1.5-300 K as well as with neutron single-crystal diffraction at 2 K and 0.12 GPa. The material undergoes an anti-isostructural phase transition at TN = 267 K and atmospheric conditions, in which both orthorhombic phases have the same space-group symmetry (Pnma, Z = 4) but different distortions of the parent hexagonal structure of the NiAs type (P63/mmc, Z = 2). The magnetic structure below TN is incommensurate with the propagation vector k = (0, 0, kc). At ambient pressure, the component kc decreases from kc = 0.3807 (7) at 260 K to kc = 0.3531 (6) at 50 K. Below this temperature, it is basically constant. With increasing pressure at 2 K, kc is also constant within standard uncertainties [kc = 0.353 (2)]. For the analysis of the magnetic structure, a group-theoretical approach based on the space group of the nuclear structure and its subgroups is used. To avoid falling into false minima in the refinements, a random search for magnetic moments in the models is implemented. In the literature, the magnetic structure has been determined on the basis of powder diffraction data as a double helix propagating along the c axis. Although this double-helical model leads to satisfactory agreement factors for our powder data, it does not reproduce the intensities of the magnetic satellite reflections measured on single-crystal data in a satisfactory way and can therefore be discarded. Instead, several other models are found that lead to better agreement. Each of them is spiral-like with directional components in all three directions and with no spin-density wave character that would cause a non-constant magnetic moment. In all these models, the ordering of the spins is neither a pure helix nor a pure cycloid. Instead, the unit vectors of the spin rotation planes make an angle α, 0° < α < 90°, with respect to the c* direction. The model in superspace group P21.1'(α0γ)0s yields the best agreement factors in the refinements of the neutron single-crystal and powder diffraction data. This model is unique as it is the only one in which all the magnetic moments rotate with the same chirality.

4.
Exp Cell Res ; 431(1): 113757, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37640260

RESUMO

Colorectal cancer (CRC) is a common malignancy worldwide nowadays and liver metastasis is the primary cause of death in patients with CRC. Although lysosomal integral membrane protein 2 (LIMP2) has been reported to play important roles in gastric cancer and prostate cancer, its role in CRC remains unclear. The aim of this study was to investigate the function of LIMP2 in CRC invasion and migration, along with the potential underlying molecular mechanisms. We found that LIMP2 levels were higher in CRC tissues compared to adjacent normal tissues. Kaplan-Meier survival analysis showed that high expression of LIMP2 was associated with worse prognosis in CRC patients. Knockdown of LIMP2 significantly inhibited invasion, migration, and wound healing abilities of CRC cells in vitro, and inhibited CRC liver metastasis in vivo. Additionally, LIMP2 knockdown inhibited autophagy in CRC. Therefore, LIMP2 plays an important role in CRC progression. High expression of LIMP2 was associated with worse prognosis in CRC patients. Knockdown LIMP2 can effectively inhibit CRC cell migration and invasion in vitro and prevent liver metastasis in vivo. These findings suggest that LIMP2 may serve as an independent prognostic factor and potential therapeutic target for CRC.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Neoplasias da Próstata , Masculino , Humanos , Movimento Celular/genética , Neoplasias Hepáticas/genética , Proteínas de Membrana Lisossomal , Neoplasias Colorretais/genética
5.
Biol Pharm Bull ; 45(9): 1238-1245, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36047191

RESUMO

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/ß-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.


Assuntos
Neoplasias Colorretais , Via de Sinalização Wnt , Benzodiazepinas , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Sistema de Sinalização das MAP Quinases , beta Catenina/metabolismo
6.
J Cancer ; 13(2): 706-714, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35069913

RESUMO

Neuronal pentraxin 2 (NPTX2), a secretory protein of neuronal pentraxins, was first identified in the nervous system. Several studies have shown that expression levels of NPTX2 are associated with the development of various cancers. However, whether NPTX2 is involved in prostate cancer progression is unclear. Herein, we found that NPTX2 is significantly reduced in prostate cancer tissues and cancer cell lines compared to control prostate tissues and control prostatic epithelial cell lines. Furthermore, the NPTX2 promoter is highly methylated in prostate cancer cells. Consistently, NPTX2 could be restored by treatment with the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine (decitabine, 5-AZA-dC). Overexpression of NPTX2 inhibited prostate cancer cell proliferation both in vitro and in vivo. In conclusion, our study demonstrated that NPTX2 acts as a tumor suppressor gene in prostate cancer.

7.
Phys Rev Lett ; 127(15): 157204, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34677991

RESUMO

Quantum spin liquids are exotic states of matter that form when strongly frustrated magnetic interactions induce a highly entangled quantum paramagnet far below the energy scale of the magnetic interactions. Three-dimensional cases are especially challenging due to the significant reduction of the influence of quantum fluctuations. Here, we report the magnetic characterization of K_{2}Ni_{2}(SO_{4})_{3} forming a three-dimensional network of Ni^{2+} spins. Using density functional theory calculations, we show that this network consists of two interconnected spin-1 trillium lattices. In the absence of a magnetic field, magnetization, specific heat, neutron scattering, and muon spin relaxation experiments demonstrate a highly correlated and dynamic state, coexisting with a peculiar, very small static component exhibiting a strongly renormalized moment. A magnetic field B≳4 T diminishes the ordered component and drives the system into a pure quantum spin liquid state. This shows that a system of interconnected S=1 trillium lattices exhibits a significantly elevated level of geometrical frustration.

8.
Sci Adv ; 7(37): eabi7532, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34516772

RESUMO

The bosonic analogs of topological insulators have been proposed in numerous theoretical works, but their experimental realization is still very rare, especially for spin systems. Recently, two-dimensional (2D) honeycomb van der Waals ferromagnets have emerged as a new platform for topological spin excitations. Here, via a comprehensive inelastic neutron scattering study and theoretical analysis of the spin-wave excitations, we report the realization of topological magnon insulators in CrXTe3 (X = Si, Ge) compounds. The nontrivial nature and intrinsic tunability of the gap opening at the magnon band-crossing Dirac points are confirmed, while the emergence of the corresponding in-gap topological edge states is demonstrated theoretically. The realization of topological magnon insulators with intrinsic gap-unability in this class of remarkable 2D materials will undoubtedly lead to new and fascinating technological applications in the domain of magnonics and topological spintronics.

9.
ACS Appl Mater Interfaces ; 13(17): 20788-20795, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33877796

RESUMO

All-oxide-based synthetic antiferromagnets (SAFs) are attracting intense research interest due to their superior tunability and great potentials for antiferromagnetic spintronic devices. In this work, using the La2/3Ca1/3MnO3/CaRu1/2Ti1/2O3 (LCMO/CRTO) superlattice as a model SAF, we investigated the layer-resolved magnetic reversal mechanism by polarized neutron reflectivity. We found that the reversal of LCMO layer moments is mediated by nucleation, expansion, and shrinkage of a magnetic soliton. This unique magnetic reversal process creates a reversed magnetic configuration of the SAF after a simple field cycling. Therefore, it can enable vertical data transfer from the bottom to the top of the superlattice. The physical origin of this intriguing magnetic reversal process could be attributed to the cooperation of the surface spin-flop effect and enhanced uniaxial magnetic anisotropy of the bottom LCMO layer. This work may pave a way to utilize all-oxide-based SAFs for three-dimensional spintronic devices with vertical data transfer and high-density data storage.

10.
Nat Commun ; 11(1): 5728, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33184278

RESUMO

A small in-plane external uniaxial pressure has been widely used as an effective method to acquire single domain iron pnictide BaFe2As2, which exhibits twin-domains without uniaxial strain below the tetragonal-to-orthorhombic structural (nematic) transition temperature Ts. 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 TN ( < Ts) and create in-plane resistivity anisotropy above Ts. Here we use neutron polarization analysis to show that such a strain on BaFe2As2 also induces a static or quasi-static out-of-plane (c-axis) AF order and its associated critical spin fluctuations near TN/Ts. Therefore, uniaxial pressure necessary to detwin single crystals of BaFe2As2 actually rotates the easy axis of the collinear AF order near TN/Ts, and such effects due to spin-orbit coupling must be taken into account to unveil the intrinsic electronic/magnetic properties of the system.

11.
J Cancer ; 11(22): 6491-6496, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33046970

RESUMO

The incidence of colorectal cancer (CRC) ranks third among all cancers in China and improvements in screening for CRC have an important impact on prevention and control of the disease. Paraoxonase 1 (PON1) is a calcium ion-dependent hydrolase that is widely distributed in tissue. Its diagnostic value in colorectal cancer has been reported, but the diagnostic value of combining PON1 with carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9), carbohydrate antigen 12-5 (CA12-5) in colorectal cancer has not been evaluated. Experiments were carried out in a total of 284 CRC patients and 90 healthy controls. The primary cohort was randomly divided into training and validation sets. The levels of PON1 in plasma of CRC patients were significantly lower than that in the healthy controls (P < 0.001). It showed excellent diagnostic value with the AUC reaching 0.750 for the training set and 0.742 for the validation set. Furthermore, combining PON1 with CEA, CA12-5, CA19-9 could better classify CRC patients (AUC rising from 0.821, 0.716, 0.712 to 0.875, 0.817 and 0.814, respectively, in the training set, from 0.818, 0.581, 0.593 to 0.854, 0.770, and 0.772 in the validation set). In conclusion, PON1 can serve as a diagnostic biomarker for CRC and raise the sensitivity and specificity when incorporated with traditional tumor biomarkers.

12.
J Phys Condens Matter ; 32(40): 405605, 2020 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-32526723

RESUMO

Temperature and field-dependent magnetization M(T, H ) measurements and neutron scattering study of a single crystal CeSb2 are presented. Several anomalies in magnetization curves have been confirmed, i.e., at 15.6 K, 12 K, and 9.8 K, respectively. These three transitions are all metamagnetic transitions, which shift to lower temperatures as the magnetic field increases. In contrast to the previous studies that the anomaly at 15.6 K has been suggested as paramagnetic to ferromagnetic phase transition, in our measurement no hysteresis loop around zero field with either H ∥ c or H ⊥ c has been observed. The anomaly located at around 12 K is antiferromagnetic-like transition, and this turning point will clearly split into two when the magnetic field H ⩾ 2 kOe. A neutron scattering study reveals that the low temperature ground state of CeSb2 orders magnetically with commensurate propagation wave vectors k = (-1, ±1/6, 0) and k = (±1/6, -1, 0), with phase transition temperature T C ∼ 9.8 K.

13.
Int J Biol Sci ; 16(8): 1417-1426, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32210729

RESUMO

Accumulating investigations have demonstrated that microRNAs (miRNAs) are promising efficient targets for the next generation of molecular therapeutics. The development of miRNA-based therapies requires the identification and validation of cancer-associated miRNAs. Herein, we identified that miR-197-3p regulates the carcinogenesis and development of prostate cancer (PCa) via bioinformatics analysis. Next, we investigated the function and regulatory mechanisms of miR-197-3p in PCa. Overexpression of miR-197-3p suppressed PCa cell proliferation and colony formation. In contrast, inhibition of miR-197-3p activity enhanced PCa cell proliferation and colony formation. Mechanistic investigations identified that voltage dependent anion channel 1 (VDAC1) is a direct target of miR-197-3p. miR-197-3p targeting of VDAC1 resulted in downregulation of p-Akt and ß-catenin. Subsequently, we found that restoration of VDAC1 abolished the effects of miR-197-3p on PCa cell proliferation and AKT signaling pathway. Furthermore, we confirmed that miR-197-3p suppressed tumor xenograft growth in vivo. In conclusion, our study offers an empirical investigation of miR-197-3p, a tumor suppressor that may be a potential therapeutic target in PCa.


Assuntos
MicroRNAs/metabolismo , Neoplasias da Próstata/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Canal de Ânion 1 Dependente de Voltagem/metabolismo , beta Catenina/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células , Biologia Computacional , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Transdução de Sinais , Via de Sinalização Wnt
14.
Microb Cell Fact ; 18(1): 209, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31791335

RESUMO

BACKGROUND: 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. RESULTS: 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/m2/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/m2/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. CONCLUSION: 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.


Assuntos
Carotenoides/metabolismo , Diatomáceas/metabolismo , Luz , Silicatos/metabolismo , Carotenoides/química , Diatomáceas/química , Silicatos/química
15.
Phys Rev Lett ; 122(11): 117204, 2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-30951336

RESUMO

We use inelastic neutron scattering to study energy and wave vector dependence of spin fluctuations in SrCo_{2}As_{2}, derived from SrFe_{2-x}Co_{x}As_{2} iron pnictide superconductors. Our data reveal the coexistence of antiferromagnetic (AF) and ferromagnetic (FM) spin fluctuations at wave vectors Q_{AF}=(1,0) and Q_{FM}=(0,0)/(2,0), respectively. By comparing neutron scattering results with those of dynamic mean field theory calculation and angle-resolved photoemission spectroscopy experiments, we conclude that both AF and FM spin fluctuations in SrCo_{2}As_{2} are closely associated with a flatband of the e_{g} orbitals near the Fermi level, different from the t_{2g} orbitals in superconducting SrFe_{2-x}Co_{x}As_{2}. Therefore, Co substitution in SrFe_{2-x}Co_{x}As_{2} induces a t_{2g} to e_{g} orbital switching, and is responsible for FM spin fluctuations detrimental to the singlet pairing superconductivity.

16.
Nat Commun ; 9(1): 5320, 2018 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-30552314

RESUMO

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-1 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 LiTi2(PO4)3/LiMn2O4 lithium-ion cell incorporating this electrolyte provided an average discharge voltage > 1.5 V and a specific energy of 77 Wh kg-1, while for an alternative cell chemistry, i.e., TiO2/LiMn2O4, a further enhanced average output voltage of 2.1 V and an initial specific energy of 124.2 Wh kg-1 are achieved.

17.
Mar Drugs ; 16(8)2018 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-30081564

RESUMO

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 Phaeodactylum tricornutum, a cosmopolitan species that has also been found in Nordic region, using the chemical mutagens ethyl methanesulfonate (EMS) and N-methyl-N'-nitro-N-nitrosoguanidine (NTG). We found that both chlorophyll a 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 P. tricornutum 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.


Assuntos
Organismos Aquáticos/genética , Carotenoides/biossíntese , Diatomáceas/genética , Redes e Vias Metabólicas/genética , Mutagênese/efeitos dos fármacos , Organismos Aquáticos/metabolismo , Clorofila/biossíntese , Clorofila A , Cromatografia Líquida , Diatomáceas/metabolismo , Metanossulfonato de Etila/toxicidade , Fluorescência , Ensaios de Triagem em Larga Escala/métodos , Metabolismo dos Lipídeos/genética , Lipídeos/biossíntese , Metilnitronitrosoguanidina/toxicidade
18.
J Phys Condens Matter ; 30(38): 385702, 2018 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-30106004

RESUMO

We present high-resolution thermal-expansion and specific-heat measurements of single crystalline α-RuCl3. An extremely hysteretic structural transition expanding over 100 K is observed by thermal-expansion along both crystallographic axes, which we attribute to a change of stacking sequence of the RuCl3 layers. Three magnetic transitions are observed, which we link to the different stacking sequences. Using our data and thermodynamic relations, we derive the uniaxial and hydrostatic pressure derivatives of all three magnetic transitions. Our results demonstrate that magnetic order of the major transition at ∼7 K should be totally suppressed by very moderate pressures of 0.3 GPa. Finally, we discuss why our results differ from recent hydrostatic pressure measurements and suggest a possible route to reaching the spin-liquid state in α-RuCl3.

19.
Methods Mol Biol ; 1852: 117-126, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30109628

RESUMO

In order to produce natural pigments with competitive prices, algal strains employed in industrial production need to be improved for increasing the productivity of valuable metabolites, thereby reducing the overall production cost. Adaptive laboratory evolution (ALE) is a traditional method for strain improvement, which has been effectively utilized in bacteria and fungi. With the growing interest in algal biotechnology, attempts have recently been put forward to improve microalgal strains with ALE approach. This chapter describes a stepwise adaptive evolution strategy that enhances carotenoid yield from microalgae.


Assuntos
Adaptação Biológica , Evolução Biológica , Carotenoides/biossíntese , Microalgas/metabolismo , Biomassa , Cromatografia Líquida de Alta Pressão , Estresse Fisiológico
20.
Environ Technol ; 39(5): 581-592, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28303757

RESUMO

In the present study, the feasibility of microalgae production coupled with wastewater treatment was assessed. Continuous cultivation of Chlorella sorokiniana with wastewater was tested in lab-scale flat-panel photobioreactors. Nitrogen and phosphorus removals were found to be inversely proportional to the four dilution rates, while chemical oxygen demand removal was found to be 50% at all the tested conditions. The biomass obtained at the highest dilution rate was characterized for its content of lipids, proteins and pigments. The average yields of fatty acid methyl esters (FAMEs), protein, lutein, chlorophylls and ß-carotene was 62.4, 388.2, 1.03, 11.82 and 0.44 mg per gram dry biomass, respectively. Economic analysis revealed that potentially more than 70% of revenue was from the production of pigments, that is, chlorophyllin (59.6%), lutein (8.9%) and ß-carotene (5.0%) while reduction in discharging costs of the treated wastewaters could account for 19.6% of the revenue. Due to the low market price of biodiesel, the revenue from the above was found to be the least profitable (1.4%). Even when combining all these different revenues, this cultivation strategy was found with the current prices to be uneconomical. Power consumption for artificial light was responsible for the 94.5% of the production costs.


Assuntos
Eliminação de Resíduos Líquidos/métodos , Análise da Demanda Biológica de Oxigênio , Chlorella/metabolismo , Microalgas/metabolismo , Nitrogênio/análise , Fósforo/análise , Fotobiorreatores , Águas Residuárias , Poluentes Químicos da Água/análise
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