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1.
Sci Rep ; 14(1): 13481, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38866850

RESUMEN

Unique architectures of microbial skeletons are viewed as a model for the architectural design of artificial structural materials. In particular, the specific geometric arrangement of a spherical skeleton 0.5-1.5 mm in diameter of shell-bearing protists, Phaeodaria (Aulosphaera sp.), is remarkably interesting because of its similarity to a geodesic polyhedron, which is a hollow framework with 6-branched nodes that requires minimal building material for maximal strength. A phaeodarian skeleton composed of silica rods 5-10 µm in diameter was characterized as a distorted dome that is based on an icosahedron sectioned with a 7-frequency subdivision. The major difference of the biogenic architecture from the ideal geodesic dome is the coexistence of 7- and 5-branched nodes with the distortion of the frames and the presence of radial spines. From a microscopic perspective, the frames and radial spines were revealed to be hollow tubes having inner fibers and lamellar walls consisting of silica nanoparticles 4-8 nm in diameter with interlayer organic matter. The high degradability of the silica skeleton in seawater after cell mortality is ascribed to the specific nanometric composite structure. The biological architectonics sheds light on the production of environmentally friendly, lightweight structural materials and microdevices.

2.
Chem Commun (Camb) ; 60(33): 4419-4422, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38505980

RESUMEN

Ultra-small metal particles having band gaps are regarded as a new class of functional materials. We investigated the size dependencies of the band-edge energies on Cu quantum-dots in the size range of 0.7-2.1 nm. The extremely high conduction band-edge energies owing to the strong quantum-size effects were observed for sizes below 1 nm.

3.
ACS Nano ; 17(3): 3135-3142, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36669094

RESUMEN

Magnesium rechargeable batteries (MRBs) promise to be the next post lithium-ion batteries that can help meet the increasing demand for high-energy, cost-effective, high-safety energy storage devices. Early prototype MRBs that use molybdenum-sulfide cathodes have low terminal voltages, requiring the development of oxide-based cathodes capable of overcoming the sulfide's low Mg2+ conductivity. Here, we fabricate an ultraporous (>500 m2 g-1) and ultrasmall (<2.5 nm) cubic spinel MgMn2O4 (MMO) by a freeze-dry assisted room-temperature alcohol reduction process. While the as-fabricated MMO exhibits a discharge capacity of 160 mAh g-1, the removal of its surface hydroxy groups by heat-treatment activates it without structural change, improving its discharge capacity to 270 mAh g-1─the theoretical capacity at room temperature. These results are made possible by the ultraporous, ultrasmall particles that stabilize the metastable cubic spinel phase, promoting both the Mg2+ insertion/deintercalation in the MMO and the reversible transformation between the cubic spinel and cubic rock-salt phases.

4.
Gan To Kagaku Ryoho ; 49(7): 775-778, 2022 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-35851349

RESUMEN

Weight loss during cancer chemotherapy affects the continuation of treatment; therefore, it is important to maintain and improve nutritional status. Additionally, appropriate fluid and electrolyte replacement is essential for maintaining life. This study included 100 patients who underwent outpatient chemotherapy in April 2021. The degree of dehydration was assessed based on serum osmolality, and the possibility of screening was examined by a hidden dehydration check sheet. Hidden dehydration was noted in 38 patients and dehydration in 6 patients. The incidence of pancreatic cancer was significantly lower than that of lung cancer. In the hidden dehydration check sheet, 51 patients were found to present with high possibility of hidden dehydration and required consultation to a medical professional. The serum osmolality of the results was not significantly different. During outpatient cancer chemotherapy, a certain percentage of patients present with hidden dehydration. To detect dehydration at an early stage, serum osmolality should be actively measured and continuous diet counseling, including confirmation of food and fluid intake, is required.


Asunto(s)
Neoplasias , Pacientes Ambulatorios , Detección Precoz del Cáncer , Humanos , Neoplasias/tratamiento farmacológico , Concentración Osmolar
5.
Chem Commun (Camb) ; 57(97): 13150-13153, 2021 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-34812452

RESUMEN

The fluorescence of benzanthrone, which is a conjugated molecule bearing a carbonyl group, is activated by confinement in a pore with a diameter close to the molecular size. An intense emission originating from the aromatic character π-π* transition is achieved through suppression of the nonradiative n-π* transition by strong hydrogen bonding between carbonyl groups and silanol groups with a micropore-filling effect in the nanospace.

6.
Angle Orthod ; 91(5): 656-663, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-33822872

RESUMEN

OBJECTIVES: To examine the torque moment that occurs between esthetic brackets and bendable alloy (stainless steel [SS], titanium-molybdenum [Ti-Mo], and titanium-niobium [Ti-Nb]) wires. MATERIALS AND METHODS: This study examined ceramic (CR), zirconium oxide (ZC), polycarbonate (PC), and conventional metallic brackets (MT) (upper, 0.018-inch and 0.022-inch slots) combined with SS, Ti-Mo, and Ti-Nb wires using elastic module ligation. The torque moments delivered by various wire and bracket combinations were measured using a torque gauge apparatus. The wire torque angles at 5-40° were examined. RESULTS: The torque value increased in the order of CR, ZC, MT, and PC brackets for both 0.018-inch and 0.022-inch slots. The fracture points of the CR and ZC brackets combined with SS and Ti-Mo wires were approximately more than 30° and 35°, respectively. No fracture points were detected in the combination of ZC brackets and Ti-Nb wires. CONCLUSIONS: The current study identified the material characteristics of CR, ZR, and PC brackets during torque tooth movements. The present results demonstrate a characteristic combined effect between different esthetic brackets and bendable alloy wires.


Asunto(s)
Soportes Ortodóncicos , Alambres para Ortodoncia , Aleaciones , Análisis del Estrés Dental , Estética Dental , Ensayo de Materiales , Diseño de Aparato Ortodóncico , Acero Inoxidable , Titanio , Torque
7.
J Biol Chem ; 296: 100372, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33548223

RESUMEN

Neural cell adhesion molecules 1 (NCAM1) and 2 (NCAM2) belong to the cell adhesion molecules of the immunoglobulin superfamily and have been shown to regulate formation, maturation, and maintenance of synapses. NCAM1 and NCAM2 undergo proteolysis, but the identity of all the proteases involved and how proteolysis is used to regulate their functions are not known. We report here that NCAM1 and NCAM2 are BACE1 substrates in vivo. NCAM1 and NCAM2 overexpressed in HEK cells were both cleaved by metalloproteinases or BACE1, and NCAM2 was also processed by γ-secretase. We identified the BACE1 cleavage site of NCAM1 (at Glu 671) and NCAM2 (at Glu 663) using mass spectrometry and site-directed mutagenesis. Next, we assessed BACE1-mediated processing of NCAM1 and NCAM2 in the mouse brain during aging. NCAM1 and NCAM2 were cleaved in the olfactory bulb of BACE1+/+ but not BACE1-/- mice at postnatal day 10 (P10), 4 and 12 months of age. In the hippocampus, a BACE1-specific soluble fragment of NCAM1 (sNCAM1ß) was only detected at P10. However, we observed an accumulation of full-length NCAM1 in hippocampal synaptosomes in 4-month-old BACE1-/- mice. We also found that polysialylated NCAM1 (PSA-NCAM1) levels were increased in BACE1-/- mice at P10 and demonstrated that BACE1 cleaves both NCAM1 and PSA-NCAM1 in vitro. In contrast, we did not find evidence for BACE1-dependent NCAM2 processing in the hippocampus at any age analyzed. In summary, our data demonstrate that BACE1 differentially processes NCAM1 and NCAM2 depending on the region of brain, subcellular localization, and age in vivo.


Asunto(s)
Secretasas de la Proteína Precursora del Amiloide/metabolismo , Ácido Aspártico Endopeptidasas/metabolismo , Antígeno CD56/metabolismo , Moléculas de Adhesión de Célula Nerviosa/metabolismo , Secretasas de la Proteína Precursora del Amiloide/fisiología , Animales , Ácido Aspártico Endopeptidasas/genética , Ácido Aspártico Endopeptidasas/fisiología , Encéfalo/metabolismo , Antígeno CD56/fisiología , Moléculas de Adhesión Celular/metabolismo , Femenino , Hipocampo/metabolismo , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Molécula L1 de Adhesión de Célula Nerviosa/metabolismo , Moléculas de Adhesión de Célula Nerviosa/fisiología , Neuronas/metabolismo , Ácidos Siálicos/metabolismo , Análisis Espacio-Temporal , Sinapsis/metabolismo
8.
Compr Psychiatry ; 96: 152148, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31756584

RESUMEN

OBJECTIVE: The Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime version (K-SADS-PL) is a widely used semi-structured diagnostic interview in child and adolescent psychiatry. However, given the extensive use of the K-SADS-PL in clinical practice and research and its adaptation for use in many languages and cultures, validation studies of the instrument are scarce. This study was designed to examine the inter-rater reliability, criterion validity and construct validity of the updated instrument, the K-SADS-PL for DSM-5, in Japanese outpatients totaling 95 children and adolescents. METHOD: We translated and adapted the updated instrument into Japanese using a standard forward-backward translation procedure. Two of nine experienced clinicians independently made diagnoses using the interview for each patient in a conjoint session. Discrepancies in diagnosis between two clinicians were resolved by consensus, and the consensus diagnosis was compared with a "best-estimate" diagnosis made by five experienced clinicians using all available data sources for patients who were blinded to the diagnosis using the K-SADS-PL for DSM-5. The "best-estimate" diagnosis of ASD was also based on the Diagnostic Interview for Social and Communication Disorders. RESULTS: The inter-rater reliability was very good, as shown by κ ≥ 0.8 for all disorders examined: autism spectrum disorder (ASD), attention-deficit hyperactivity disorder, tic disorders, selective mutism, enuresis and encopresis. The criterion validity was good, as shown by κ ≥ 0.6 for all disorders examined, except for ASD (κ = 0.59). This study also revealed good construct validity of the instrument by confirming the expected associations with each scale from the Social Responsiveness Scale-2nd edition and the Strengths and Difficulties Questionnaire. CONCLUSION: These results suggest that the K-SADS-PL for DSM-5 generates valid diagnoses in child and adolescent psychiatry.


Asunto(s)
Trastorno del Espectro Autista/diagnóstico , Trastornos de la Conducta Infantil/diagnóstico , Escalas de Valoración Psiquiátrica , Adolescente , Niño , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Humanos , Japón , Masculino , Pacientes Ambulatorios , Reproducibilidad de los Resultados , Traducciones
9.
Langmuir ; 35(16): 5594-5598, 2019 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-30924656

RESUMEN

Supermicroporous silicas having micropores 1-2 nm in diameter were miniaturized to 30-40 nm in diameter using a combination of binary organic agents: cationic surfactant as a porogen and polyethylene glycol as a growth suppressor in a concentrated system. The miniaturized nanograins of the porous silica were effective as a porous and transparent matrix for WO3 quantum dots that exhibit enhanced photocatalytic activity.

10.
Langmuir ; 33(12): 3014-3017, 2017 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-28271895

RESUMEN

The size of In2O3 quantum dots (QDs) is tuned from 0.57 to 1.80 nm by using supermicroporous silicas (SMPSs) as a template. The band gap energy and photoluminescence quantum yields of In2O3-QDs increase remarkably when their size is decreased below 1 nm.

11.
Chem Commun (Camb) ; 52(36): 6185-8, 2016 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-27075304

RESUMEN

The conduction band edge (CBE) of WO3 quantum dots (QDs) was determined experimentally and engineered by size control to around one nanometer. Photocatalytic reactions of proton and molecular oxygen were tuned by changing the CBE of WO3-QDs.

12.
Angew Chem Int Ed Engl ; 53(40): 10706-9, 2014 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-25132195

RESUMEN

1 nm CuO quantum dots (QDs) were produced in size-controlled super-micropores of a silica matrix. The reversible color change of the QDs from pale blue to deep green was clearly observed in a wide temperature range from 298 to 673 K. This particular thermochromism is ascribed to an enhanced bandgap shift depending on temperature with a strong electron-phonon coupling in the confined space of the 1 nm QDs.

13.
Dent Mater J ; 33(3): 363-7, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24786348

RESUMEN

The objective of the study was to measure the torque moment delivered by a novel elastic bendable wire, Ti-Nb wire, and to compare it with nickel-titanium (Ni-Ti) and titanium-molybdenum (Ti-Mo) alloy wires. Two sizes of Ti-Nb, Ni-Ti and Ti-Mo alloy wires and 0.022-inch slot stainless steel brackets were ligated with elastic modules or ligature wires. The torque moment delivered by the various wire-bracket combinations was measured using a torque gauge at the temperature and humidity of 37°C and 50%, respectively. As the degree of applied torque and the inserted wire size increased, the torque moment gradually increased. The torque moment of Ti-Nb wires was smaller than those of Ni-Ti wires and Ti-Mo wires, at more than 20 degrees applied torque. The torque moment with wire ligation was significantly larger than those with elastic ligation.


Asunto(s)
Alambres para Ortodoncia , Torque , Elasticidad , Movimiento
14.
Chem Commun (Camb) ; 49(76): 8477-9, 2013 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-23938767

RESUMEN

The band-gap energy tuning of WO3 quantum dots was realized in the range of 2.6 eV (bulk) to 3.7 eV (sub-nano) by precise size control around one nanometer. Newly synthesized sub-nanoporous silicas act as excellent templates. In addition, single-electron reduction of oxygen under UV irradiation is now achievable with WO3.

15.
Org Lett ; 4(19): 3313-6, 2002 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-12227777

RESUMEN

[reaction: see text] Enantioselective borohydride reduction, catalyzed by the optically active beta-ketoiminato cobalt(II) complex, was successfully applied to the 1,1'-dialkanoyl- and 1,1'-dibenzoylferrocenes to afford the corresponding C(2)-symmetrical chiral ferrocenyl diols with high diastereoselectivity and excellent enantioselectivity.

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