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1.
Nat Immunol ; 21(12): 1540-1551, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33020660

RESUMO

The metabolic challenges present in tumors attenuate the metabolic fitness and antitumor activity of tumor-infiltrating T lymphocytes (TILs). However, it remains unclear whether persistent metabolic insufficiency can imprint permanent T cell dysfunction. We found that TILs accumulated depolarized mitochondria as a result of decreased mitophagy activity and displayed functional, transcriptomic and epigenetic characteristics of terminally exhausted T cells. Mechanistically, reduced mitochondrial fitness in TILs was induced by the coordination of T cell receptor stimulation, microenvironmental stressors and PD-1 signaling. Enforced accumulation of depolarized mitochondria with pharmacological inhibitors induced epigenetic reprogramming toward terminal exhaustion, indicating that mitochondrial deregulation caused T cell exhaustion. Furthermore, supplementation with nicotinamide riboside enhanced T cell mitochondrial fitness and improved responsiveness to anti-PD-1 treatment. Together, our results reveal insights into how mitochondrial dynamics and quality orchestrate T cell antitumor responses and commitment to the exhaustion program.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Contagem de Linfócitos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Dinâmica Mitocondrial/imunologia , Biomarcadores , Epigênese Genética , Epigenômica , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/imunologia , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Mitofagia , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/terapia , Niacinamida/farmacologia , Receptor de Morte Celular Programada 1/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais , Estresse Fisiológico , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
2.
J Environ Manage ; 351: 119763, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38071921

RESUMO

Rhizosphere is a soil volume of high spatio-temporal heterogeneity and intensive plant-soil-microbial interactions, for which visualization and process quantification is of highest scientific and applied relevance, but still very challenging. A novel methodology for quick assessment of two-dimensional distribution of available phosphorus (P) in rhizosphere was suggested, tested, and development up to the application platform. Available P was firstly trapped by an in-situ diffusive gradients in thin-films (DGT) sampler with precipitated zirconia as the binding gel, and subsequently, the loaded gel was analyzed with an optimized colorimetric imaging densitometry (CID). The imaging platform was established linking: i) DGT, ii) planar optode, and iii) soil zymography techniques to simultaneously determine available P, oxygen, and acid phosphatase in rhizosphere at sub-millimeter spatial scales. The DGT identified available P level in rice rhizosphere were spatially overlapping to the localized redox hotspots and phosphatase activity. The spatial relationship between available P and acid phosphatase activity was dependent on root development. The root radial oxygen loss (ROL) remained active during the experimental observations (2-3 days), while a flux of available P of 10 pg cm-2 s-1 was visualized within 2-3 mm of roots, confirming the correlative response of rice roots to oxygen secretion and P uptake. Summarizing, the established imaging platform is suitable to capture spatial heterogeneity and temporal dynamics of root activities, nutrient bioavailability, ROL and enzyme activities in rhizosphere.


Assuntos
Oryza , Fósforo , Fósforo/metabolismo , Rizosfera , Solo , Oxigênio/metabolismo , Fosfatase Ácida/metabolismo , Raízes de Plantas/metabolismo
3.
J Org Chem ; 88(22): 15871-15880, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37882877

RESUMO

Herein, we report a novel method for the synthesis of thioesters and acyl disulfides via nickel-catalyzed reductive cross-electrophile coupling of acid chlorides with tetrasulfides. This approach for the synthesis of thioesters and acyl disulfides is convenient and practical under mild reaction conditions, relying on easy availability. In addition, a wide range of thioesters and acyl disulfides were obtained in medium to good yields with good functional group tolerance. Moreover, thioesters and acyl disulfides can also be prepared at the gram scale, indicating that they have certain potential for industrial application.

4.
Neurochem Res ; 47(8): 2244-2253, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35585298

RESUMO

Nicotinamide adenine dinucleotide (NAD) is a critical cosubstrate for enzymes involved in supplying energy to the brain. Nicotinamide riboside (NR), an NAD+ precursor, emerges as a neuroprotective factor after chronic brain insults. However, researchers have not determined whether it improves cognition after acute ischemia. In the present study, mice with middle cerebral artery occlusion were treated with NR chloride (NRC, 300 mg/kg, IP., 20 min after reperfusion). The results of the Morris water maze test revealed better recovery of learning and memory function in the NRC-treated group. Acute NRC treatment decreased hippocampal infarct volume, reduced neuronal loss and apoptosis in the hippocampus. Western blot and high-performance liquid chromatography assays of hippocampal tissues revealed that the activation of Sirtin-1 and adenosine 5' monophosphate-activated protein kinase was increased, the NAD content was elevated, and the production of adenosine triphosphate was strengthened by NRC. Collectively, acute NRC treatment increased the energy supply, reduced the neuronal loss and apoptosis, protected the hippocampus and ultimately promoted the recovery of cognitive function after brain ischemia.


Assuntos
Cloretos , NAD , Animais , Cognição , Hipocampo/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Camundongos , NAD/metabolismo , Niacinamida/análogos & derivados , Compostos de Piridínio
5.
Clin Rehabil ; 36(5): 693-702, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34985366

RESUMO

OBJECTIVES: Repetitive peripheral magnetic stimulation (rPMS) is a non-invasive method that activates peripheral nerves and enhances muscle strength. This study aimed to investigate the effect of rPMS applied in early subacute stroke on severe upper extremity impairment. DESIGN: Randomized controlled trial. SETTING: Rehabilitation department of a university hospital. SUBJECTS: People aged 30-80 years with no practical arm function within four weeks of a first stroke. INTERVENTIONS: Participants were randomly assigned to either the rPMS group (n = 24, 20Hz and 2400 pulses of rPMS to triceps brachii and extensor digitorum muscles daily for two weeks in addition to conventional physiotherapy) or the control group (n = 20, conventional physiotherapy). MAIN MEASURES: The primary outcome was the upper extremity motor section of Fugl-Meyer Assessment after treatment. Secondary outcomes included Barthel Index and root mean square of surface electromyography for muscle strength and stretch-induced spasticity of critical muscles of the upper extremity. Data presented: mean (SD) or median (IQR). RESULTS: The rPMS group showed more significant improvements in the Fugl-Meyer Assessment (12.5 (2.5) vs. 7.0 (1.4), P < 0.001), Barthel Index (15 (5) vs. 10 (3.7), P < 0.001), and strength-root mean square (biceps brachii: 20.5 (4.8) vs. 6.2 (2.7), p < 0.001; triceps brachii: 14.9 (5.8) vs. 4.3 (1.2), p < 0.001; flexor digitorum: 5.1 (0.8) vs. 4.0 (1.1), p < 0.001) compared with the control group. CONCLUSION: In patients with no functional arm movement, rPMS of upper limb extensors improves arm function and muscle strength for grip and elbow flexion and extension.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Fenômenos Magnéticos , Pessoa de Meia-Idade , Espasticidade Muscular , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico , Reabilitação do Acidente Vascular Cerebral/métodos , Resultado do Tratamento , Extremidade Superior
6.
Phys Rev Lett ; 127(18): 187003, 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34767423

RESUMO

Whether the doped t-J model on the Kagome lattice supports exotic superconductivity has not been decisively answered. In this Letter, we propose a new class of variational states for this model and perform a large-scale variational Monte Carlo simulation on it. The proposed variational states are parameterized by the SU(2)-gauge rotation angles, as the SU(2)-gauge structure hidden in the Gutzwiller-projected mean-field Ansatz for the undoped model is broken upon doping. These variational doped states smoothly connect to the previously studied U(1) π-flux or 0-flux states, and energy minimization among them yields a chiral noncentrosymmetric nematic superconducting state with 2×2-enlarged unit cell. Moreover, this pair density wave state possesses a finite Fermi surface for the Bogoliubov quasiparticles. We further study experimentally relevant properties of this intriguing pairing state.

7.
Phys Rev Lett ; 125(15): 157002, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33095631

RESUMO

It has long been proposed that doping a chiral spin liquid (CSL) or fractional quantum Hall state can give rise to topological superconductivity. Despite intensive effort, definitive evidences still remain lacking. We address this problem by studying the t-J model supplemented by time-reversal symmetry breaking chiral interaction J_{χ} on the triangular lattice using density-matrix renormalization group with a finite concentration δ of doped holes. It has been established that the undoped, i.e., δ=0, system has a CSL ground state in the parameter region 0.32≤J_{χ}/J≤0.56. Upon light doping, we find that the ground state of the system is consistent with a Luther-Emery liquid with power-law superconducting and charge-density-wave correlations but short-range spin-spin correlations. In particular, the superconducting correlations, whose pairing symmetry is consistent with d±id wave, are dominant at all hole doping concentrations. Our results provide direct evidences that doping the CSL on the triangular lattice can naturally give rise to topological superconductivity.

8.
Neuropsychobiology ; 79(3): 198-207, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31940619

RESUMO

BACKGROUND: Depression is one of the most common neuropsychiatric disturbances in Parkinson's disease (PD), but its pathophysiology is not definite. Lines of evidence have indicated that the hippocampus and serotonin 1A (5-HT1A) receptors are related to the regulation of depression. OBJECTIVE: The purpose of the present study was to observe the effect of 5-HT1A receptors in the dorsal hippocampus (dHIP) on PD-related depression in rats. METHODS: Unilateral 6-hydroxydopamine lesioning of the medial forebrain bundle (MFB) was used to establish the hemiparkinsonian rat model. The effects of intra-dHIP injection of the 5-HT1A receptor -agonist 8-hydroxy-2-(dipropylamino)tetralin hydrobromide (8-OH-DPAT) or antagonist WAY-100635 on depressive-like behaviors were observed in sucrose preference and forced swim tests in control and lesioned rats. Monoamine levels including dopamine (DA), 5-HT, and noradrenaline (NA) in depression-related brain regions were determined by a neurochemical method in all groups. RESULTS: Behavioral results showed that MFB lesions induced depressive-like behaviors. Intra-dHIP injection of 8-OH-DPAT produced antidepressant effects, while WAY-100635 induced or increased the depressive-like behaviors in both control and the lesioned rats. Neurochemical results found that intra-dHIP injection of 8-OH-DPAT significantly increased DA and 5-HT levels in the medial prefrontal cortex (mPFC), lateral habenula (LHb), ventral hippocampus and amygdala in the lesioned group and decreased NA levels in the mPFC and LHb in the control group. Moreover, after injection of WAY-100635, NA levels in all these regions of the lesioned group were significantly increased. CONCLUSIONS: These findings suggest that hippocampal 5-HT1A receptors regulate depression and PD-related depression by neurochemical mechanisms.


Assuntos
Comportamento Animal/efeitos dos fármacos , Depressão , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Doença de Parkinson/complicações , Receptor 5-HT1A de Serotonina/metabolismo , Agonistas do Receptor 5-HT1 de Serotonina/farmacologia , Antagonistas da Serotonina/farmacologia , 8-Hidroxi-2-(di-n-propilamino)tetralina/farmacologia , Tonsila do Cerebelo/efeitos dos fármacos , Tonsila do Cerebelo/metabolismo , Animais , Depressão/induzido quimicamente , Depressão/tratamento farmacológico , Depressão/etiologia , Depressão/metabolismo , Modelos Animais de Doenças , Habenula/efeitos dos fármacos , Habenula/metabolismo , Masculino , Feixe Prosencefálico Mediano/lesões , Piperazinas/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Piridinas/farmacologia , Ratos , Ratos Sprague-Dawley , Agonistas do Receptor 5-HT1 de Serotonina/administração & dosagem , Antagonistas da Serotonina/administração & dosagem
9.
Bioorg Med Chem ; 27(13): 2801-2812, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31079967

RESUMO

Deregulation of receptor tyrosine kinase c-Met has been reported in human cancers and is considered as an attractive target for small molecule drug discovery. In this study, a series of 4-phenoxyquinoline derivatives bearing sulfonylurea moiety were designed, synthesized and evaluated for their c-Met kinase inhibition and cytotoxicity against tested four cell lines in vitro. The pharmacological data indicated that most of the tested compounds showed moderate to significant potency as compared with foretinib, with the most promising compound 13x (c-Met kinase IC50 = 1.98 nM) demonstrated relatively good selectivity versus 10 other tyrosine kinases and remarkable cytotoxicities against HT460, MKN-45, HT-29 and MDA-MB-231 with IC50 values of 0.055 µM, 0.064 µM, 0.16 µM and 0.49 µM, respectively. The preliminary structure activity relationships indicated that a sulfonylurea moiety as linker as well as mono-EGWs (such as R1 = 4-F) on the terminal phenyl rings contributed to the antitumor activity.


Assuntos
Inibidores de Proteínas Quinases/uso terapêutico , Compostos de Sulfonilureia/química , Compostos de Sulfonilureia/síntese química , Humanos , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/farmacologia , Relação Estrutura-Atividade
10.
Anal Chem ; 90(5): 3335-3340, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29411603

RESUMO

A highly sensitive and selective colorimetric assay based on a multifunctional molecular beacon with palindromic tail (PMB) was proposed for the detection of target p53 gene. The PMB probe can serve as recognition element, primer, and polymerization template and contains a nicking site and a C-rich region complementary to a DNAzyme. In the presence of target DNA, the hairpin of PMB is opened, and the released palindromic tails intermolecularly hybridize with each other, triggering the autonomous polymerization/nicking/displacement cycles. Although only one type of probe is involved, the system can execute triple and continuous polymerization strand displacement amplifications, generating large amounts of G-quadruplex fragments. These G-rich fragments can bind to hemin and form the DNAzymes that possess the catalytic activity similar to horseradish peroxidase, catalyzing the oxidation of ABTS by H2O2 and producing the colorimetric signal. Utilizing the newly proposed sensing system, target DNA can be detected down to 10 pM with a linear response range from 10 pM to 200 nM, and mutant target DNAs are able to be distinguished even by the naked eye. The desirable detection sensitivity, high specificity, and operation convenience without any separation step and chemical modification demonstrate that the palindromic molecular beacon holds the potential for detecting and monitoring a variety of nucleic acid-related biomarkers.


Assuntos
Colorimetria/métodos , DNA Catalítico/química , DNA/análise , Genes p53/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Sequência de Bases , Benzotiazóis/química , Técnicas Biossensoriais/métodos , Compostos Cromogênicos/química , DNA/genética , DNA Catalítico/genética , Neoplasias/diagnóstico , Neoplasias/genética , Hibridização de Ácido Nucleico , Ácidos Sulfônicos/química
12.
Small ; 13(18)2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28296136

RESUMO

Efficient and durable oxygen evolution reaction (OER) catalysts are highly required for the cost-effective generation of clean energy from water splitting. For the first time, an integrated OER electrode based on one-step direct growth of metallic iron-nickel sulfide nanosheets on FeNi alloy foils (denoted as FeNi3 S2 /FeNi) is reported, and the origin of the enhanced OER activity is uncovered in combination with theoretical and experimental studies. The obtained FeNi3 S2 /FeNi electrode exhibits highly catalytic activity and long-term stability toward OER in strong alkaline solution, with a low overpotential of 282 mV at 10 mA cm-2 and a small Tafel slope of 54 mV dec-1 . The excellent activity and satisfactory stability suggest that the as-made electrode provides an attractive alternative to noble metal-based catalysts. Combined with density functional theory calculations, exceptional OER performance of FeNi3 S2 /FeNi results from a combination of efficient electron transfer properties, more active sites, the suitable O2 evolution kinetics and energetics benefited from Fe doping. This work not only simply constructs an excellent electrode for water oxidation, but also provides a deep understanding of the underlying nature of the enhanced OER performance, which may serve as a guide to develop highly effective and integrated OER electrodes for water splitting.

13.
Phys Rev Lett ; 119(10): 107202, 2017 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-28949178

RESUMO

Proposed as a fundamental symmetry describing our Universe, spacetime supersymmetry (SUSY) has not been discovered yet in nature. Nonetheless, it has been predicted that SUSY may emerge in low-energy physics of quantum materials such as topological superconductors and Weyl semimetals. Here, by performing state-of-the-art sign-problem-free quantum Monte Carlo simulations of an interacting two-dimensional topological superconductor, we show convincing evidence that the N=1 SUSY emerges at its edge quantum critical point (EQCP) while its bulk remains gapped and topologically nontrivial. Remarkably, near the EQCP, we find that the edge Majorana fermion acquires a mass that is identical with that of its bosonic superpartner. To the best of our knowledge, this is the first observation that fermions and bosons have equal dynamically generated masses, a hallmark of emergent SUSY. We further discuss experimental signatures of such EQCP and associated SUSY.

14.
Chemistry ; 23(62): 15680-15693, 2017 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-28782857

RESUMO

In this work, five new cadmium metal-organic frameworks (Cd-MOFs 1-5) have been synthesized from solvothermal reactions of Cd(NO3 )2 ⋅4 H2 O with isophthalic acid and 1,4-bis(imidazol-1-yl)-benzene under different solvent systems of CH3 OH, C2 H5 OH, (CH3 )2 CHOH, DMF, and N-methyl-2-pyrrolidone (NMP), respectively. Cd-MOF 1 shows a 3D diamondoid framework with 1D rhombic and hexagonal channels, and the porosity is 12.9 %. Cd-MOF 2 exhibits a 2D (4,4) layer with a 1D parallelogram channel and porosity of 23.6 %. Cd-MOF 3 has an 8-connected dense network with the Schäfli symbol of [424 ⋅64 ] based on the Cd6 cluster. Cd-MOFs 4-5 are isomorphous, and display an absolutely double-bridging 2D (4,4) layer with 1D tetragonal channels and porosities of 29.2 and 28.2 %, which are occupied by DMF and NMP molecules, respectively. Followed by the calcination-thermolysis procedure, Cd-MOFs 1-5 are employed as precursors to prepare MOF-derived porous carbon materials (labeled as PC-me, PC-eth, PC-ipr, PC-dmf and PC-nmp), which have the BET specific surface area of 23, 51, 10, 122, and 96 m2 g-1 , respectively. The results demonstrate that the specific surface area of PCs is tuned by the porosity of Cd-MOFs, where the later is highly dependent on the solvent. Thereby, the specific surface area of PCs could be adjusted by the solvent used in the synthese of MOF precusors. Significantly, PCs have been further activated by KOH to obtain activated carbon materials (APCs), which possess even higher specific surface area and larger porosity. After a series of characterization and electrochemical investigations, the APC-dmf electrode exhibits the best porous properties and largest specific capacitances (153 F g-1 at 5 mV s-1 and 156 F g-1 at 0.5 Ag-1 ). Meanwhile, the APC-dmf electrode shows excellent cycling stability (ca. 84.2 % after 5000 cycles at 1 Ag-1 ), which can be applied as a suitable electrode material for supercapacitors.

15.
Inorg Chem ; 56(11): 6184-6196, 2017 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-28524653

RESUMO

Herein three novel cobalt metal-organic frameworks (Co-MOFs) with similar ingredients, [Co(bib)(o-bdc)]∞ (1), [Co2(bib)2(m-bdc)2]∞ (2), and {[Co(bib)(p-bdc)(H2O)](H2O)0.5}∞ (3), have been synthesized from the reaction of cobalt nitrate with 1,4-bis(imidazol-1-yl)benzene (bib) and structure-related aromatic acids (1,2-benzenedicarboxylic acid = o-bdc, 1,3-benzenedicarboxylic acid = m-bdc, and 1,4-benzenedicarboxylic acid = p-bdc) by the solvothermal method. It is aimed to perform systematic research on the relationship among the conformation of benzoate acid, lattice dimension of Co-MOF, and pore diameter of MOF-derived carbon composite. Through the precursor strategy, Co-MOFs 1-3 have been utilized to synthesize porous cobalt@carbon nanotube composites (Co@CNTs). After the in situ gas-sulfurization, secondary composites CoS2@CNTs were successfully obtained, which kept similar morphologies of corresponding Co@CNTs without destroying previous highly dispersed structures. Co-MOFs and two series of composites (Co@CNTs and CoS2@CNTs) have been well characterized. Topology and Brunauer-Emmett-Teller analyses elucidate that the bdc2- ion could control the pore diameters of MOF-derived carbon composites by adjusting the lattice dimension of Co-MOFs. The systematic studies on electrochemical properties demonstrate that (p)-CoS2@CNT possesses hierarchical morphology, moderate specific surface area, proper pore diameter distribution, and high graphitization, which lead to remarkable specific capacitances (839 F g-1 at 5 mV s-1 and 825 F g-1 at 0.5 A g-1) in 2 M potassium hydroxide solution. In addition, the (p)-CoS2@CNT electrode exhibits good electrochemical stability and still retains 82.9% of initial specific capacitance at the current density of 1 A g-1 after 5000 cycles.

17.
Phys Rev Lett ; 117(26): 267002, 2016 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-28059531

RESUMO

A fundamental open issue in physics is whether and how the fermion sign problem in quantum Monte Carlo (QMC) simulations can be solved generically. Here, we show that Majorana-time-reversal (MTR) symmetries can provide a unifying principle to solve the fermion sign problem in interacting fermionic models. By systematically classifying Majorana-bilinear operators according to the anticommuting MTR symmetries they respect, we rigorously prove that there are two and only two fundamental symmetry classes which are sign-problem-free and which we call the "Majorana class" and "Kramers class," respectively. Novel sign-problem-free models in the Majorana class include interacting topological superconductors and interacting models of charge-4e superconductors. We believe that our MTR unifying principle could shed new light on sign-problem-free QMC simulation on strongly correlated systems and interacting topological matters.

18.
Langmuir ; 32(35): 8980-7, 2016 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-27556281

RESUMO

Oxygen-sensitive photoreversible intelligent ink capable of assessment with the human eye is an ongoing demand in the modern era. In the food industry, redox-dye-based oxygen indicator films have been proposed, but the leaching of dyes from the film that contaminates the food is one unsolved issue. On the other hand, it is also highly desirable to develop rewritable paper that significantly reduces the pressure on modern society for the production and consumption of paper. Herein, we have developed an oxygen-deficient TiO2 - x/methylene blue (MB) sol without relying on external sacrificial electron donors (SEDs) for photoreversible color switching. Oxygen vacancies in TiO2 - x can work as electron donor to favor the adsorption of the substrate and improve the charge separation that is required for the redox-based color-switching system. The problems of rewriteable paper and food packaging are addressed as two sides of a single coin in this article. We have used hydroxyethyl cellulose (HEC) for rewritable paper that can significantly delay the oxidation of leuco-MB (LMB) through hydrogen bonding and retain the printed information for a long time. The dye leaching from oxygen indicator films is also significantly reduced (only 1.54%) by using furcelleran as the coating polymer that is extracted from edible red seaweed.

19.
Phys Rev Lett ; 114(23): 237001, 2015 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-26196823

RESUMO

Supersymmetry (SUSY) interchanges bosons and fermions but no direct evidence of it has been revealed in nature yet. In this Letter, we observe that fluctuating pair density waves (PDW) consist of two complex order parameters which can be superpartners of the unavoidably doubled Weyl fermions in three-dimensional lattice models. We construct explicit fermionic lattice models featuring 3D Weyl fermions and show that PDW is the leading instability via a continuous phase transition as short-range interactions exceed a critical value. Using a renormalization group, we theoretically show that N=2 space-time SUSY emerges at the continuous PDW transitions in 3D Weyl semimetals, which we believe is the first realization of emergent (3+1)D space-time SUSY in microscopic lattice models. We further discuss possible routes to realize such lattice models and experimental signatures of emergent SUSY at the PDW criticality.

20.
Chem Asian J ; 19(11): e202400086, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38676953

RESUMO

A visible light-catalyzed radical coupling reaction of polysulfide reagents with aryldiazonium was developed, which gave thiosulfonates under mild conditions. In this reaction, the thiosulfonates were isolated in good yields with a broad tolerance to functional groups. And the synthesis of diaryl monosulfides were achieved through a step-by-step reaction of two molecular aryldiazonium with DBSPS, where the sulfur source was provided by DBSPS. It was worth noting that the reaction of this monosulfides could also be achieved by a one pot two-step process. The described polysulfide reagents were able to produce three new radicals: sulfonyl radicals, sulfur-sulfonyl radicals and sulfur-sulfur-sulfonyl radicals.

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