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In-plane mesopatterns derived from block-copolymer (BCP) micro-phase segregation in thin films have attracted much interest in practical applications as well as fundamental research programs. However, phase segregation along the film-normal direction has been less studied. Here, we describe a strategy to concurrently, yet independently, control in-plane micro-phase and out-of-plane macro-phase segregation in multiblended films composed of liquid-crystalline BCPs (LCBCPs), affording spontaneously layered three-dimensional (3D) mesostructures. This strategy relies on sequential liquid crystallization during the cooling process in thermal annealing as follows. The constituent LCBCP with the highest isotropic-transition temperature (Tiso) first liquid-crystallizes and segregates from the other LCBCP mixture remaining in isotropic states to form a noncontaminated layer at the top surface. This preformed LCBCP layer preserves its inherent in-plane pattern and acts as a template guiding the subsequent micro-phase segregations of the other low-Tiso LCBCPs underneath. This self-template-assisted micro-phase segregation (STAMPS) readily provides 3D mesostructures, the potential toward rational material design of which is also demonstrated in water-separation applications.
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The existing methods for determining adult age from human skeletons are mostly qualitative. However, a shift in quantifying age-related skeletal morphology on a quantitative scale is emerging. This study describes an intuitive variable extraction technique and quantifies skeletal morphology in continuous data to understand their aging pattern. A total of 200 postmortem CT images from the deceased aged 25-99 years (130 males, 70 females) who underwent forensic death investigations were used in the study. The 3D volume of the fourth lumbar vertebral body was segmented, smoothed, and post-processed using the open-source software ITK-SNAP and MeshLab, respectively. To measure the extent of 3D shape deformity due to aging, the Hausdorff distance (HD) analysis was performed. In our context, the maximum Hausdorff distance (maxHD) was chosen as a metric, which was subsequently studied for its correlation with age at death. A strong statistically significant positive correlation (P < 0.001) between maxHD and age at death was observed in both sexes (Spearman's rho = 0.742, male; Spearman's rho = 0.729, female). In simple linear regression analyses, the regression equations obtained yielded the standard error of estimates of 12.5 years and 13.1 years for males and females, respectively. Our study demonstrated that age-related vertebral morphology could be described using the HD method. Moreover, it encourages further studies with larger sample sizes and on other population backgrounds to validate the methodology.
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Auger electrons can induce nanoscale physiochemical damage to DNA. The present study reports a sequential and systematic evaluation of the relationship between DNA damage such as double-strand breaks (DSBs) and the cell cycle for the Auger electron-emitting agent radiolabeled cisplatin with DNA binding ability. For dynamic imaging analysis, we used U2OS-derived cancer cells expressing two fluorescent fusion proteins: tumor-suppressor p53 binding protein 1 with a green fluorescent protein (53BP1-EGFP) and proliferating cell nuclear antigen with a red fluorescent protein (PCNA-DsRed). Time-lapse images of the cells were quantitatively analyzed using the ImageJ software with the deepImageJ plugin and the Google Colaboratory platform. From the middle-to-late G1 phase, around the G1-to-S phase transition, we found increased 53BP1 foci in cells treated with the radio-cisplatin. The radio-cisplatin caused significantly more DSBs than the nonradioactive cisplatin and saline in the G1 phase but not in the other phases. These results indicate that Auger electron-induced DNA damage, including DSBs, depends on the cell cycle. The G1 phase, which is associated with low DNA repair capacity and high radiosensitivity, is a promising target; thus, combining radiolabeled cisplatin with agents that arrest cells in the G1 phase could improve the DNA-damaging effect of Auger electrons and their therapeutic efficacy.
Assuntos
Cisplatino , Elétrons , Cisplatino/farmacologia , Divisão Celular , Ciclo Celular , Dano ao DNARESUMO
This study evaluated the age-related changes in the vertebral body using 3D Postmortem CT (PMCT) images and proposed an alternative age estimation formula. The PMCT images of 200 deceased individuals aged 25 to 99 years (126 males, 74 females) were retrospectively reviewed and included in the study. Using the open-source software ITK-SNAP and MeshLab, a 3D surface mesh of the fourth lumbar vertebral body (L4) and its convex hull models were created from the PMCT data. Using their inbuilt tools, volumes (in mm3) of the L4 surface mesh and convex hull models were subsequently computed. We derived VD, defined as the difference in volumes between the convex hull and L4 surface mesh normalized by L4 mesh volume, and VR, defined as the ratio of L4 mesh volume to convex hull volume based on individual L4. Correlation and regression analyses were performed between VD, VR, and chronological age. A statistically significant positive correlation (P < 0.001) between chronological age and VD, (rs = 0.764, males; rs = 0.725, females), and a significant negative correlation between chronological age and VR (rs = -0.764, males; rs = -0.725, females) was obtained in both sexes. The lowest standard error of the estimate was demonstrated by the VR at 11.9 years and 12.5 years for males and females, respectively. As such, their regression models to estimate adult age were Age = 248.9-2.5VR years, males; Age = 258.1-2.5VR years, females. These regression equations may be useful for estimating age in Japanese adults in forensic settings.
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População do Leste Asiático , Corpo Vertebral , Masculino , Feminino , Adulto , Humanos , Estudos Retrospectivos , Imageamento Tridimensional , Análise de RegressãoRESUMO
BACKGROUND: Use of the Glatzel mirror for measuring expiratory nasal flow in preschool children has the disadvantage of vagueness, and the mirror may induce fear and inhibition of interest in those children. In response to these limitations, we developed a new device with dual cameras for measuring expiratory nasal flow in 2 to 6 year old children. The aim of this study is to compare the Glatzel mirror and the new device, in terms of accurate assessment of expiratory nasal flow, children's feelings, and correlation to each child's profile. METHODS: This study evaluated 20 cleft lip and palate patients and 21 healthy children aged between 2 and 6 (under 7) years. After consent was granted, a 4-week screening period was undertaken followed by inspection at weeks 8, 16, 24, and 32. Each inspection was conducted while the children were asked to pronounce various sounds and comprised three stages: i) use of the Glatzel mirror, ii) subjective visual assessment using the new device, and iii) image recording by dual cameras of the new device. Questionnaires for the new device were administered at the initial and final inspections. To contrast the results between the Glatzel mirror and the new device, the numbers that indicated values of subjective visual assessment and camera assessment greater than the assessment values of the Glatzel mirror were compared. For measuring the children's responses to the new device compared with those to the Glatzel mirror, the answers to the questionnaires were compared. For the comparison of the children's profiles (age and sex) and feelings, the numbers of subjects who could use the new device were measured. RESULTS: The camera assessment of the new device indicated significantly greater values than that of the Glatzel mirror (P < 0.05). The feelings of the subjects to the new device mostly improved as the study progressed. Subjects aged 3 years and older were generally able to use the new device from the initial inspection. For both sexes, as the inspection progressed, the number occasions of successful use increased. CONCLUSION: This study demonstrated the superiority of the new device with dual cameras to the Glatzel mirror in terms of functionality and attitude of children.
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A technique to measure the temperature of water and non-turbid aqueous media surrounding an induction-heated small magnetic sphere is presented. This technique utilizes wavelengths of 1150 and 1412 nm, at which the absorption coefficient of water is dependent on temperature. Water or a non-turbid aqueous gel containing a 2.0-mm- or 0.5-mm-diameter magnetic sphere is irradiated with 1150 nm or 1412 nm incident light, as selected using a narrow bandpass filter; additionally, two-dimensional absorbance images, which are the transverse projections of the absorption coefficient, are acquired via a near-infrared camera. When the three-dimensional distributions of temperature can be assumed to be spherically symmetric, they are estimated by applying inverse Abel transforms to the absorbance profiles. The temperatures were observed to consistently change according to time and the induction heating power.
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Magnetismo/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Água/química , Temperatura Alta , TemperaturaRESUMO
Measurement of volume and surface area of the frontal, parietal, temporal and occipital lobes from magnetic resonance (MR) images shows promise as a method for use in diagnosis of dementia. This article presents a novel computer-aided system for automatically segmenting the cerebral lobes from 3T human brain MR images. Until now, the anatomical definition of cerebral lobes on the cerebral cortex is somewhat vague for use in automatic delineation of boundary lines, and there is no definition of cerebral lobes in the interior of the cerebrum. Therefore, we have developed a new method for defining cerebral lobes on the cerebral cortex and in the interior of the cerebrum. The proposed method determines the boundaries between the lobes by deforming initial surfaces. The initial surfaces are automatically determined based on user-given landmarks. They are smoothed and deformed so that the deforming boundaries run along the hourglass portion of the three-dimensional shape of the cerebrum with fuzzy rule-based active contour and surface models. The cerebrum is divided into the cerebral lobes according to the boundaries determined using this method. The reproducibility of our system with a given subject was assessed by examining the variability of volume and surface area in three healthy subjects, with measurements performed by three beginners and one expert user. The experimental results show that our system segments the cerebral lobes with high reproducibility.
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Algoritmos , Córtex Cerebral/anatomia & histologia , Lógica Fuzzy , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Reconhecimento Automatizado de Padrão/métodos , Humanos , Aumento da Imagem/métodos , Armazenamento e Recuperação da Informação/métodos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
A conventional ultrasonography system can noninvasively provide human tissue and blood flow velocity information with real-time processing. In general, since the human skull prevents the disclosure of brain anatomy, we usually placed the sensor at the anterior and superior attachment site of the upper ear (the posterior temporal window) in adults. Due to this limitation, the conventional system cannot obtain transcranial information from arbitrary places in the skull. This paper describes a transcranial sonography system that can visualize the shape of the skull and brain surface from any point to examine skull fracture and brain disease such as cerebral atrophy and epidural or subdural hematoma. In this system, we develop anatomical knowledge of the human head, and we employ fuzzy inference to determine the skull and brain surface. To evaluate our method, three models are applied: the phantom model, the animal model with soft tissue, and the animal model with brain tissue. In all models, the shapes of the skull and the brain tissue surface are successfully determined. Next, the method is applied to two adults. As a result, we have determined the skin surface, skull surface, skull bottom, and brain tissue surface for the subjects' foreheads. Consequently, our system can provide the skull and brain surface information using three-dimensional shapes.
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Sistemas Inteligentes , Lógica Fuzzy , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Reconhecimento Automatizado de Padrão/métodos , Crânio/diagnóstico por imagem , Ultrassonografia Doppler Transcraniana/métodos , Algoritmos , Humanos , Aumento da Imagem/métodos , Armazenamento e Recuperação da Informação/métodos , Modelos Biológicos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
The absolute stereochemistry of FD-594 1, a new cytotoxic antibiotic, was determined by X-ray diffraction, and its conformation was studied by CD and NMR spectroscopy. The aglycon part of 1 was found to have (3R,6S,7S) configuration. Particularly interesting was the solvent-dependent atropisomerism of 1 and related compounds. The CD spectra of 1 exhibited in two solvent systems almost opposite mirror-image curves depending on the solvent. While a large negative Cotton effect (Deltaepsilon = -33.9, 279 nm) was observed in CHCl(3), a similar positive Cotton effect (Deltaepsilon = 38.9, 279 nm) appeared in methanol most probably due to dramatic conformational changes. Similar chiroptical reversal was observed in aglycon 2 and aglycon methyl ether 4. These results can be best described in terms of solvent-dependent atropisomerism. This constitutes the first observation of solvent-dependent atropisomerism of a natural product. The crucial factor that perturbs the stable conformation in different solvents is discussed on the basis of molecular mechanics calculations.
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This paper presents a remote and preparation-free method of temperature imaging of aqueous solutions in microchannels of microfluidic chips. The principle of this method is based on the temperature dependency of the near-infrared (NIR) absorption band (ν(2) + ν(3) band) of water. Temperature images were constructed from absorbances in a narrow wavelength range including 1908 nm, the most sensitive to temperature in the band, measured by using an NIR camera and an optical narrow-bandpass filter. Calculation and calibration results demonstrated a linear relationship between the absorption coefficient and temperature with a temperature coefficient of 1.5 × 10(-2) K(-1) mm(-1). Temperature images of 50 µm thick water in a Y-shaped PDMS microchannel locally heated by a neighboring hot wire were obtained, in which thermal diffusion processes in the microchip were visualized. Temperature resolution was estimated to be approximately 0.2 K according to the temperature coefficient and noise level.