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1.
J Am Chem Soc ; 146(37): 25527-25535, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39248728

RESUMO

Singlet fission (SF) is a promising approach in quantum information science because it can generate spin-entangled quintet triplet pairs by photoexcitation independent of temperature. However, it is still challenging to rationally achieve quantum coherence at room temperature, which requires precise control of the orientation and dynamics of triplet pairs. Here we show that the quantum coherence of quintet multiexcitons can be achieved at room temperature by arranging two pentacene chromophores in parallel and in close proximity within a macrocycle. By making dynamic covalent Schiff-base bonds between aldehyde-modified pentacene derivatives, macrocyclic parallel dimer-1 (MPD-1) can be selectively synthesized in a high yield. MPD-1 exhibits fast subpicosecond SF in polystyrene film and generates spin-polarized quintet multiexcitons. Furthermore, the coherence time T2 of the MPD-1 quintet is as long as 648 ns, even at room temperature. This macrocyclic parallel dimer strategy opens up new possibilities for future quantum applications using molecular multilevel qubits.

2.
Hepatol Res ; 54(10): 888-898, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38804859

RESUMO

AIM: Measurement of O-glycosylated middle hepatitis B surface antigen (HBsAg glycan isomer, HBsAgGi) has been developed to quantify hepatitis B virus (HBV) infectious virions and distinguish them from subviral particles. This study aimed to evaluate the association between serum HBsAg seroclearance and serum HBV virions measured by HBsAgGi in patients with chronic hepatitis B (CHB). METHODS: Serum HBsAgGi levels were quantified in 232 treatment-naïve patients with CHB genotype C. Cox proportional hazards analysis was used to calculate hazard ratios (HRs) for factors associated with HBsAg seroclearance. RESULTS: Baseline HBsAgGi levels showed significant differences among HBV phenotypes. During a median follow-up period of 7.4 years, 22 of the 232 patients achieved HBsAg seroclearance. Multivariate analysis demonstrated that quantitative HBsAg, nucleoside/nucleotide analog therapy during the follow-up period, and HBsAgGi levels were independent predictors of seroclearance. The adjusted HR indicated that the HBsAg seroclearance probability in patients with low HBsAgGi (≤3.5log ng/mL) was over five times higher than that in patients with high HBsAgGi. Kaplan-Meier analysis indicated that the 10-year probabilities of HBsAg seroclearance were 21.0% and 3.0% in patients with low and high HBsAgGi levels, respectively (p < 0.001), and that patients with high HBsAgGi levels showed low seroclearance probabilities irrespective of the other predictors. CONCLUSION: Serum HBV infectious virion levels, measured using HBsAgGi, may be a novel predictor of HBsAg seroclearance.

3.
Int Psychogeriatr ; 36(1): 64-77, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36714996

RESUMO

OBJECTIVES: We aimed to investigate the association between very late-onset schizophrenia-like psychosis (VLOSLP), a schizophrenia spectrum disorder with an onset of ≥60 years, and Alzheimer's disease (AD) using biomarkers. DESIGN: Retrospective cross-sectional study. SETTING: Neuropsychology clinic of Osaka University Hospital in Japan. PARTICIPANTS: Thirty-three participants were classified into three groups: eight AD biomarker-negative VLOSLP (VLOSLP-AD), nine AD biomarker-positive VLOSLP (VLOSLP+AD), and sixteen amnestic mild cognitive impairment due to AD without psychosis (aMCI-P+AD) participants. MEASUREMENTS: Phosphorylated tau levels in the cerebrospinal fluid and 18F-Florbetapir positron emission tomography results were used as AD biomarkers. Several scales (e.g. the Mini-Mental State Examination (MMSE), Wechsler Memory Scale-Revised (WMS-R) Logical Memory (LM) I and II, and Neuropsychiatric Inventory (NPI)-plus) were conducted to assess clinical characteristics. RESULTS: Those in both VLOSLP-AD and +AD groups scored higher than those in aMCI-P+AD in WMS-R LM I. On the other hand, VLOSLP+AD participants scored in between the other two groups in the WMS-R LM II, with only VLOSLP-AD participants scoring significantly higher than aMCI-P+AD participants. There were no significant differences in sex distribution and MMSE scores among the three groups or in the subtype of psychotic symptoms between VLOSLP-AD and +AD participants. Four VLOSLP-AD and five VLOSLP+AD participants harbored partition delusions. Delusion of theft was shown in two VLOSLP-AD patients and five VLOSLP+AD patients. CONCLUSION: Some VLOSLP patients had AD pathology. Clinical characteristics were different between AD biomarker-positive and AD biomarker-negative VLOSLP, which may be helpful for detecting AD pathology in VLOSLP patients.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Transtornos Psicóticos , Esquizofrenia , Humanos , Esquizofrenia/diagnóstico , Doença de Alzheimer/psicologia , Estudos Transversais , Estudos Retrospectivos , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/psicologia , Disfunção Cognitiva/psicologia , Biomarcadores , Peptídeos beta-Amiloides/líquido cefalorraquidiano
4.
Proc Natl Acad Sci U S A ; 118(31)2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34315818

RESUMO

Optical cavities confine light on a small region in space, which can result in a strong coupling of light with materials inside the cavity. This gives rise to new states where quantum fluctuations of light and matter can alter the properties of the material altogether. Here we demonstrate, based on first-principles calculations, that such light-matter coupling induces a change of the collective phase from quantum paraelectric to ferroelectric in the [Formula: see text] ground state, which has thus far only been achieved in out-of-equilibrium strongly excited conditions [X. Li et al., Science 364, 1079-1082 (2019) and T. F. Nova, A. S. Disa, M. Fechner, A. Cavalleri, Science 364, 1075-1079 (2019)]. This is a light-matter hybrid ground state which can only exist because of the coupling to the vacuum fluctuations of light, a photo ground state The phase transition is accompanied by changes in the crystal structure, showing that fundamental ground state properties of materials can be controlled via strong light-matter coupling. Such a control of quantum states enables the tailoring of materials properties or even the design of novel materials purely by exposing them to confined light.

5.
Psychogeriatrics ; 24(2): 281-294, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38152057

RESUMO

BACKGROUND: We aimed to validate the Clinical Dementia Rating (CDR®) dementia staging instrument plus the National Alzheimer's Coordinating Centre Behaviour and Language Domains (CDR® plus NACC FTLD) for use in clinical settings in Japan and in the Japanese language. METHODS: This prospective observational study enrolled 29 patients with frontotemporal dementia (FTD) and 21 patients with Alzheimer's disease (AD) dementia from the Departments of Psychiatry at Osaka University Hospital and Asakayama General Hospital and the Brain Function Centre at Nippon Life Hospital. CDR® plus NACC FTLD, CDR®, Mini-Mental State Examination (MMSE), Western Aphasia Battery (WAB), Neuropsychiatric Inventory-plus (NPI-plus), Stereotypy Rating Inventory (SRI), and frontal behavioural symptom scores obtained from items of NPI-plus and SRI, were conducted to assess inter- and intra-rater reliability, validity, and responsiveness. We performed receiver operating characteristic (ROC) curve analysis to evaluate the discriminating power of the Behaviour/Comportment/Personality (BEHAV) and Language (LANG) domains of the CDR® plus NACC FTLD and the MEMORY domain of the CDR® in patients AD dementia and FTD. RESULTS: The CDR® plus NACC FTLD showed good inter- and intra-rater reliabilities. In patients with FTD, the BEHAV domain of the CDR® plus NACC FTLD was significantly correlated with all clinical measures except for the SRI total score, while the LANG domain of the CDR® plus NACC FTLD was significantly correlated with the MMSE and the WAB-Aphasia quotient. In addition, the CDR® plus NACC FTLD sum of boxes significantly changed after 6 months and after 1 year. ROC curve analysis showed that the BEHAV and LANG domains of the CDR® plus NACC FTLD distinguished between patients with AD dementia and FTD better than the MEMORY domain of the CDR®. CONCLUSIONS: This study validated the Japanese version of the CDR® plus NACC FTLD with good reliability, validity, and responsiveness.


Assuntos
Doença de Alzheimer , Afasia , Demência Frontotemporal , Doença de Pick , Humanos , Demência Frontotemporal/diagnóstico , Doença de Alzheimer/diagnóstico , Japão , Reprodutibilidade dos Testes , Testes de Estado Mental e Demência , Idioma
6.
Kyobu Geka ; 77(1): 38-41, 2024 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-38459844

RESUMO

Off-pump totally-endoscopic surgery for atrial fibrillation is reported. This procedure is also called the Wolf-Ohtsuka procedure or totally thoracoscopic maze (TT-maze) surgery. It is a minimally invasive left atrial appendage management and surgical ablation. The wound is limited to that required for port placement, and the patient recovers quickly. Advantages over WATCHMAN include the that it can be applied regardless of the size of the left atrial appendage, can be performed even if there is a thrombus at the tip of the left atrial appendage, and no wound or device comes on the endocardial side. Advantages over catheter ablation is the potential for embolism prevention by simultaneously performing ablation and the left atrial appendage management. The tips and techniques for this procedure are also described here.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Ablação por Cateter , Humanos , Fibrilação Atrial/cirurgia , Apêndice Atrial/cirurgia , Resultado do Tratamento , Toracoscopia/métodos , Ablação por Cateter/métodos
7.
Angew Chem Int Ed Engl ; 63(22): e202403886, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38545689

RESUMO

The photocatalytic reduction of carbon dioxide (CO2) represents an attractive approach for solar-energy storage and leads to the production of renewable fuels and valuable chemicals. Although some osmium (Os) photosensitizers absorb long wavelengths in the visible-light region, a self-photosensitized, mononuclear Os catalyst for red-light-driven CO2 reduction has not yet been exploited. Here, we discovered that the introduction of an Os metal to a PNNP-type tetradentate ligand resulted in the absorption of light with longer-wavelength (350-700 nm) and that can be applied to a panchromatic self-photosensitized catalyst for CO2 reduction to give mainly carbon monoxide (CO) with a total turnover number (TON) of 625 under photoirradiation (λ≥400 nm). CO2 photoreduction also proceeded under irradiation with blue (λ0=405 nm), green (λ0=525 nm), or red (λ0=630 nm) light to give CO with >90 % selectivity. The quantum efficiency using red light was determined to be 12 % for the generation of CO. A catalytic mechanism is proposed based on the detection of intermediates using various spectroscopic techniques, including transient absorption, electron paramagnetic resonance, and UV/Vis spectroscopy.

8.
Acc Chem Res ; 55(7): 933-943, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-34851099

RESUMO

The synthesis of organic chemicals from H2O and CO2 using solar energy is important for recycling CO2 through cyclical use of chemical ingredients produced from CO2 or molecular energy carriers based on CO2. Similar to photosynthesis in plants, the CO2 molecules are reduced by electrons and protons, which are extracted from H2O molecules, to produce O2. This reaction is uphill; therefore, the solar energy is stored as the chemical bonding energy in the organic molecules. This artificial photosynthetic technology mimicking green vegetation should be implemented as a self-standing system for on-site direct solar energy storage that supports CO2 recycling in a circular economy. Herein, we explain our interdisciplinary fusion methodology to develop hybrid photocatalysts and photoelectrodes for an artificial photosynthetic system for the CO2 reduction reaction (CO2RR) in aqueous solutions. The key factor for the system is the integration of uniquely different functions of molecular transition-metal complexes and solid semiconductors. A metal complex catalyst and a semiconductor appropriate for a CO2RR and visible-light absorption, respectively, are linked, and they function complementary way to catalyze CO2RR under visible-light irradiation as a particulate photocatalyst dispersion in solution. It has also been proven that Ru complexes with bipyridine ligands can catalyze a CO2RR as photocathodes when they are linked with various semiconductor surfaces, such as those of doped tantalum oxides, doped iron oxides, indium phosphides, copper-based sulfides, selenides, silicon, and others. These photocathodes can produce formate and carbon monoxide using electrons and protons extracted from water through potential-matched connections with photoanodes such as TiO2 or SrTiO3 for oxygen evolution reactions (OERs). Benefiting from the very low overpotential of an aqueous CO2RR at metal complexes approaching the theoretical lower limit, the semiconductor/molecule hybrid system demonstrates a single tablet-formed monolithic electrode called "artificial leaf." This single electrode device can generate formate (HCOO-) from H2O and CO2 in a water-filled single-compartment reactor without requiring a separation membrane under unassisted or bias-free conditions, either electrically or chemically. The reaction proceeds with a stoichiometric electron/hole ratio and stores solar energy with a solar-to-chemical energy conversion efficiency of 4.6%, which exceeds that of plants. In this Account, the key results that marked our milestones in technological progress of the semiconductor/molecule hybrid photosystem are concisely explained. These results include design, proof of the principle, and understanding of the phenomena by time-resolved spectroscopies, synchrotron radiation analyses, and DFT calculations. These results enable us to address challenges toward further scientific progress and the social implementation, including the use of earth-abundant elements and the scale-up of the solar-driven CO2RR system.


Assuntos
Dióxido de Carbono , Fotossíntese , Dióxido de Carbono/química , Folhas de Planta , Semicondutores , Luz Solar
9.
Chemphyschem ; 24(8): e202200927, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-36594677

RESUMO

Reentrant phenomena in soft matter and biosystems have attracted considerable attention because their properties are closely related to high functionality. Here, we report a combined experimental and computational study on the self-assembly and reentrant behavior of a single-component thermotropic smectic liquid crystal toward the realization of dynamically functional materials. We have designed and synthesized a mesogenic molecule consisting of an alicyclic trans,trans-bicyclohexyl mesogen and a polar cyclic carbonate group connected by a flexible tetra(oxyethylene) spacer. The molecule exhibits an unprecedented sequence of layered smectic phases, in the order: smectic A-smectic B-reentrant smectic A. Electron density profiles and large-scale molecular dynamics simulations indicate that competition between the stacking of bicyclohexyl mesogens and the conformational flexibility of tetra(oxyethylene) chains induces this unusual reentrant behavior. Ion-conductive reentrant liquid-crystalline materials have been developed, which undergo the multistep conductivity changes in response to temperature. The reentrant liquid crystals have potential as new mesogenic materials exhibiting switching functions.

10.
Chemphyschem ; 24(8): e202300192, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37066767

RESUMO

The front cover artwork is provided by Takashi Kato at the University of Tokyo. The image shows three assembled structures of smectic liquid crystals that show reentrant behavior. Read the full text of the Research Article at 10.1002/cphc.202200927.

11.
Nano Lett ; 22(3): 881-887, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35084202

RESUMO

A magnetic skyrmion induced on a ferromagnetic topological insulator (TI) is a real-space manifestation of the chiral spin texture in the momentum space and can be a carrier for information processing by manipulating it in tailored structures. Here, a sandwich structure containing two layers of a self-assembled ferromagnetic septuple-layer TI, Mn(Bi1-xSbx)2Te4 (MnBST), separated by quintuple layers of TI, (Bi1-xSbx)2Te3 (BST), is fabricated and skyrmions are observed through the topological Hall effect in an intrinsic magnetic topological insulator for the first time. The thickness of BST spacer layer is crucial in controlling the coupling between the gapped topological surface states in the two MnBST layers to stabilize the skyrmion formation. The homogeneous, highly ordered arrangement of the Mn atoms in the septuple-layer MnBST leads to a strong exchange interaction therein, which makes the skyrmions "soft magnetic". This would open an avenue toward a topologically robust rewritable magnetic memory.

12.
Molecules ; 28(8)2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37110789

RESUMO

The understanding and control of the rheological behaviors of colloids and polymer mixtures is an important issue for scientific interests and industrial applications. Aqueous mixed suspensions of silica nanoparticles and poly(ethylene oxide) (PEO) under certain conditions are interesting systems called "shake-gels", whose states vary reversibly between sol-like and gel-like under repeated shaking and being left to stand. Previous studies have indicated that the amount of PEO dose per silica surface area (Cp) is a crucial parameter for the formation of shake-gels and the relaxation time from gel-like to sol-like states. However, the relationship between the gelation dynamics and the Cp values has not been fully investigated. To determine how the gelation dynamics are affected by the Cp, we measured the time taken for silica and PEO mixtures to gelate from the sol-like to gel-like states as a function of the Cp under different shear rates and flow types. Our results show that the gelation time decreased with increasing shear rates and depended on the Cp values. Moreover, the minimum gelation time was found around a certain Cp (=0.03 mg/m2) for the first time. The finding suggests that there is an optimum Cp value at which the bridging of silica nanoparticles using PEO is significant, and thus, the shake-gels and stable gel-like states are most likely to form.

13.
Opt Express ; 30(8): 12248-12267, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35472864

RESUMO

The first step to gain optical control over the ultrafast processes initiated by light in solids is a correct identification of the physical mechanisms at play. Among them, exciton formation has been identified as a crucial phenomenon which deeply affects the electro-optical properties of most semiconductors and insulators of technological interest. While recent experiments based on attosecond spectroscopy techniques have demonstrated the possibility to observe the early-stage exciton dynamics, the description of the underlying exciton properties remains non-trivial. In this work we propose a new method called extended Ptychographic Iterative engine for eXcitons (ePIX), capable of reconstructing the main physical properties which determine the evolution of the quasi-particle with no prior knowledge of the exact relaxation dynamics or the pump temporal characteristics. By demonstrating its accuracy even when the exciton dynamics is comparable to the pump pulse duration, ePIX is established as a powerful approach to widen our knowledge of solid-state physics.

14.
Phys Rev Lett ; 129(16): 167401, 2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36306771

RESUMO

Recent experiments have demonstrated that light can induce a transition from the quantum paraelectric to the ferroelectric phase of SrTiO_{3}. Here, we investigate this terahertz field-induced ferroelectric phase transition by solving the time-dependent lattice Schrödinger equation based on first-principles calculations. We find that ferroelectricity originates from a light-induced mixing between ground and first excited lattice states in the quantum paraelectric phase. In agreement with the experimental findings, our study shows that the nonoscillatory second harmonic generation signal can be evidence of ferroelectricity in SrTiO_{3}. We reveal the microscopic details of this exotic phase transition and highlight that this phenomenon is a unique behavior of the quantum paraelectric phase.

15.
BMC Gastroenterol ; 22(1): 270, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35641912

RESUMO

BACKGROUND: Serum hepatitis B surface antigen (HBsAg) is a component of both hepatitis B virus (HBV) virions and non-infectious subviral particles (SVPs). Recently, O-glycosylation of the PreS2 domain of middle HBsAg protein has been identified as a distinct characteristic of genotype C HBV virions versus SVPs. This study aimed to evaluate serum O-glycosylated HBsAg levels in patients with chronic hepatitis B (CHB) treated with nucleos(t)ide analogs (NAs). METHODS: Forty-seven treatment-naïve patients with genotype C CHB were retrospectively enrolled. Serum O-glycosylated HBsAg levels at baseline and after 48 weeks of NA therapy were quantified by immunoassay using a monoclonal antibody against the O-glycosylated PreS2 domain of middle HBsAg, and their correlations with conventional HBV marker levels were analyzed. RESULTS: At baseline, the serum O-glycosylated HBsAg levels were significantly correlated with the HBV DNA (P = 0.004), HBsAg (P = 0.005), and hepatitis B-core related antigen (HBcrAg, P = 0.001) levels. Both HBV DNA and O-glycosylated HBsAg levels were decreased after 48 weeks of NA therapy. The significant correlation of the O-glycosylated HBsAg level with the HBsAg or HBcrAg level was lost in patients who achieved undetectable HBV DNA (HBsAg, P = 0.429; HBcrAg, P = 0.065). Immunoprecipitation assays demonstrated that HBV DNA and RNA were detected in the O-glycosylated HBsAg-binding serum fraction, and the proportion of HBV RNA increased during NA therapy (P = 0.048). CONCLUSION: Serum O-glycosylated HBsAg levels change during NA therapy and may reflect combined levels of serum HBV DNA and RNA virions. An O-glycosylated HBsAg-based immunoassay may provide a novel means to monitor viral kinetics during NA therapy.


Assuntos
Hepatite B Crônica , DNA Viral , Glicosilação , Antígenos de Superfície da Hepatite B , Hepatite B Crônica/tratamento farmacológico , Humanos , RNA , Estudos Retrospectivos
16.
BMC Gastroenterol ; 22(1): 478, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36411436

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is usually asymptomatic and lacks a specific biomarker; therefore, many individuals might remain undiagnosed even with advanced liver fibrosis. The aim of this study was to clarify the prevalence and clinical features of subjects with a high risk of advanced liver fibrosis in the general population, using the Fibrosis-4 (FIB-4) index. METHODS: We retrospectively investigated 6,087 subjects without known liver disease who had participated in an annual health checkup examination. We analyzed the factors associated with high FIB-4 index (≥ 2.67) using a logistic regression analysis. RESULTS: Among the 6,087 subjects, 76 (1.2%) had high FIB-4 index. Multivariate analysis identified hypertension (odds ratio [OR]; 9.040; 95% confidence interval [CI], 4.081-20.024; P < 0.001) and diabetes mellitus (OR = 4.251; 95% CI, 1.773-10.193; P = 0.001) as important risk factors for high FIB-4 index. The rates of hypertension and diabetes mellitus in subjects with high FIB-4 index were 78.9% and 23.7%, respectively. No significant association was observed between obesity or large waist circumference and high FIB-4 index. A history of cardiovascular disease was significantly more common in subjects with high FIB-4 index. These results were also observed in subjects with normal liver function test. CONCLUSIONS: The present study revealed that approximately 1% of the general Japanese population has a high risk of advanced liver fibrosis. Many of these patients had hypertension and/or diabetes mellitus. Our findings suggest that there are many undiagnosed patients NAFLD with risk of advanced liver fibrosis in the general population.


Assuntos
Diabetes Mellitus , Hipertensão , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Estudos Retrospectivos , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Cirrose Hepática/diagnóstico , Cirrose Hepática/epidemiologia , Cirrose Hepática/complicações , Hipertensão/epidemiologia , Hipertensão/complicações
17.
Appl Microbiol Biotechnol ; 106(8): 3021-3032, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35451630

RESUMO

Poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate] (PHBHHx) is a type of biopolyester of the polyhydroxyalkanoate group (PHA). Due to a wide range of properties resulting from the alteration of the (R)-3-hydroxyhexanoate (3HHx) composition, PHBHHx is getting a lot of attention as a substitute to conventional plastic materials for various applications. Cupriavidus necator H16 is the most promising PHA producer and has been genetically engineered to produce PHBHHx efficiently for many years. Nevertheless, the role of individual genes involved in PHBHHx biosynthesis is not well elaborated. C. necator H16 possesses six potential physiologically active ß-ketothiolase genes identified by transcriptome analysis, i.e., phaA, bktB, bktC (h16_A0170), h16_A0462, h16_A1528, and h16_B0759. In this study, we focused on the functionality of these genes in vivo in relation to 3HHx monomer supply. Gene deletion experiments identified BktB and H16_A1528 as important ß-ketothiolases for C6 metabolism in ß-oxidation. Furthermore, in the bktB/h16_A1528 double-deletion strain, the proportion of 3HHx composition of PHBHHx produced from sugar was very low, whereas that from plant oil was significantly higher. In fact, the proportion reached 36.2 mol% with overexpression of (R)-specifc enoyl-CoA hydratase (PhaJ) and PHA synthase. Furthermore, we demonstrated high-density production (196 g/L) of PHBHHx with high 3HHx (32.5 mol%) by fed-batch fermentation with palm kernel oil. The PHBHHx was amorphous according to the differential scanning calorimetry analysis. KEY POINTS: • Role of six ß-ketothiolases in PHBHHx biosynthesis was investigated in vivo. • Double-deletion of bktB/h16_A1528 results in high 3HHx composition with plant oil. • Amorphous PHBHHx with 32.5 mol% 3HHx was produced in high density by jar fermenter.


Assuntos
Cupriavidus necator , Poli-Hidroxialcanoatos , Acetil-CoA C-Aciltransferase/genética , Acetil-CoA C-Aciltransferase/metabolismo , Cupriavidus necator/genética , Cupriavidus necator/metabolismo , Hidroxibutiratos/metabolismo , Óleos de Plantas/metabolismo , Poli-Hidroxialcanoatos/metabolismo
18.
J Chem Phys ; 156(16): 164705, 2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35490024

RESUMO

We applied hot-carrier extraction to particulate photocatalysts for artificial photosynthetic reactions including water splitting for H2 production and CO2 reduction to CO and HCOOH, and elucidated promising features of hot-carrier photocatalysts (HC-PCs). We designed a specific structure of the HC-PC; a semiconductor core in which thermalization of photo-generated carriers is significantly suppressed is surrounded by a shell whose bandgap is wider than that of the core. Among the photo-generated hot carriers in the core, only carriers whose energies are larger than the shell bandgap are extracted passing through the shell to the active sites on the shell surface. Thus, the shell functions as an energy-selective contact. We calculated the upper bounds of the rates of the carrier supply from the core to the active sites using a newly constructed detailed-balance model including partial thermalization and nonradiative recombination of the carriers. It has been revealed that the HC-PCs can yield higher carrier-supply rates and thus potentially higher solar-to-chemical energy conversion efficiencies for H2 and CO production than those of conventional photocatalysts with the assistance of intraband transition and Auger recombination/impact ionization. It should be noted, however, that one of the necessary conditions for efficient hot-carrier extraction is sufficiently large carrier density in the core, which, in turn, requires concentrated solar illumination by several hundreds. This would raise rate-limiting problems of activities of the chemical reactions induced by the photo-generated carriers and material-transfer properties.


Assuntos
Fotossíntese , Semicondutores , Temperatura Alta , Água/química
19.
Proc Natl Acad Sci U S A ; 116(10): 4135-4140, 2019 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-30765519

RESUMO

Materials can be classified by the topological character of their electronic structure and, in this perspective, global attributes immune to local deformations have been discussed in terms of Berry curvature and Chern numbers. Except for instructional simple models, linear response theories have been ubiquitously used in calculations of topological properties of real materials. Here we propose a completely different and versatile approach to obtain the topological characteristics of materials by calculating physical observables from the real-time evolving Bloch states: The cell-averaged current density reveals the anomalous velocities that lead to the conductivity quantum. Results for prototypical cases are shown, including a spin-frozen valley Hall and a quantum anomalous Hall insulator. The advantage of this method is best illustrated by the example of a quantum spin Hall insulator: The quantized spin Hall conductivity is straightforwardly obtained irrespective of the non-Abelian nature in its Berry curvature. Moreover, the method can be extended to the description of real observables in nonequilibrium states of topological materials.

20.
Acta Med Okayama ; 76(4): 439-446, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36123159

RESUMO

This study examined the relationship between cognitive/structural social capital and post-traumatic stress disorder (PTSD) among victims of heavy rain and flood. Participants were individuals aged≥18 years affected by the July 2018 heavy rainfall in the cities of Kurashiki and Soja, Japan, and living in temporary housing. We distributed five copies of a questionnaire to 1,991 households and received responses from 1,927 individuals (907 men, 1,008 women, 12 respondents of unspecified sex) in 1,029 households (51.7%). We estimated odds ratios (ORs) and 95% confidence intervals (CIs) for associations between high (vs. low) social capital and PTSD or other outcomes. After covariate adjustment, the odds of having PTSD were lower in participants with high cognitive social capital than those with low cognitive social capital (OR=0.346, 95%CI: 0.263-0.456). Elderly women with higher structural social capital tended to have lower PTSD odds than those with lower structural social capital (OR=0.671, 95%CI: 0.431-1.046). The opposite pattern was observed for elderly men (OR=1.315, 95%CI: 0.792-2.183). Cognitive social capital is a protective factor that may reduce PTSD or promote a favorable PTSD prognosis after heavy rainfall and flood events. The associations between structural social capital and PTSD differ by age and sex.


Assuntos
Capital Social , Transtornos de Estresse Pós-Traumáticos , Idoso , Desastres , Feminino , Inundações , Humanos , Japão/epidemiologia , Masculino , Apoio Social , Transtornos de Estresse Pós-Traumáticos/epidemiologia
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