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1.
Micromachines (Basel) ; 13(8)2022 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-36014192

RESUMO

In this paper, we describe a newly developed vision feedback method for improving the placement accuracy and success rate of a single nozzle capillary force gripper. The capillary force gripper was developed for the pick-and-place of mm-sized objects. The gripper picks up an object by contacting the top surface of the object with a droplet formed on its nozzle and places the object by contacting the bottom surface of the object with a droplet previously applied to the place surface. To improve the placement accuracy, we developed a vision feedback system combined with two cameras. First, a side camera was installed to capture images of the object and nozzle from the side. Second, from the captured images, the contour of the pre-applied droplet for placement and the contour of the object picked up by the nozzle were detected. Lastly, from the detected contours, the distance between the top surface of the droplet for object release and the bottom surface of the object was measured to determine the appropriate amount of nozzle descent. Through the experiments, we verified that the size matching effect worked reasonably well; the average placement error minimizes when the size of the cross-section of the objects is closer to that of the nozzle. We attributed this result to the self-alignment effect. We also confirmed that we could control the attitude of the object when we matched the shape of the nozzle to that of the sample. These results support the feasibility of the developed vision feedback system, which uses the capillary force gripper for heterogeneous and complex-shaped micro-objects in flexible electronics, micro-electro-mechanical systems (MEMS), soft robotics, soft matter, and biomedical fields.

2.
Sci Rep ; 11(1): 17948, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34504173

RESUMO

Topological data analysis is an emerging concept of data analysis for characterizing shapes. A state-of-the-art tool in topological data analysis is persistent homology, which is expected to summarize quantified topological and geometric features. Although persistent homology is useful for revealing the topological and geometric information, it is difficult to interpret the parameters of persistent homology themselves and difficult to directly relate the parameters to physical properties. In this study, we focus on connectivity and apertures of flow channels detected from persistent homology analysis. We propose a method to estimate permeability in fracture networks from parameters of persistent homology. Synthetic 3D fracture network patterns and their direct flow simulations are used for the validation. The results suggest that the persistent homology can estimate fluid flow in fracture network based on the image data. This method can easily derive the flow phenomena based on the information of the structure.

3.
J Org Chem ; 86(12): 8500-8507, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34096302

RESUMO

This work describes the synthesis of PCBM ([6,6]-phenyl-C61-butyric acid methyl ester) derivatives and other methanofullerene derivatives via generation of fullerene radical anions under photoirradiation and controlled by photoswitching, without preparation, a strong reducing agent, or precise control of the reaction conditions.

4.
Org Biomol Chem ; 17(10): 2629-2634, 2019 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-30768088

RESUMO

Regio-purity in [70]fullerene derivatives is of great importance to improve the power conversion efficiencies of organic photovoltaics. We found that the introduction of a branched structure to [70]PCBM enhanced the yield of α-isomers. The effect of the steric group in the reaction mechanism was theoretically investigated and a difference in the activation energies within specific pathways was revealed.

5.
J Oral Sci ; 59(1): 1-11, 2017 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-27725369

RESUMO

We investigated the prevalences and risk factors for peri-implant diseases in Japanese adult dental patients attending a follow-up visit at dental hospitals or clinics as part of their maintenance program. This cross-sectional multicenter study enrolled patients with dental implants who attended regular check-ups as part of a periodontal maintenance program during the period from October 2012 through September 2013. Patients with implants with at least 3 years of loading time were included in the study. The condition of peri-implant tissue was examined and classified into the following categories: healthy, peri-implant mucositis, and peri-implantitis. Patients were also evaluated for implant risk factors. A total of 267 patients (110 men, 157 women; mean age: 62.5 ± 10.7 years) were analyzed. The prevalence of patient-based peri-implant mucositis was 33.3% (n = 89), and the prevalence of peri-implantitis was 9.7% (n = 26). Poor oral hygiene and a history of periodontitis were strong risk factors for peri-implant disease. The present prevalences were lower than those previously reported. The quality of periodontal therapy before and after implant installation and patient compliance and motivation, as indicated by plaque control level, appear to be important in maintaining peri-implant tissue health.


Assuntos
Peri-Implantite/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Adulto Jovem
6.
Oncol Lett ; 12(2): 1132-1138, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27446407

RESUMO

Saturation prostate biopsy protocols have been developed to improve the prostate cancer (PCa) detection rate, particularly in the setting of repeat biopsies. The present study attempted to clarify the association between PCa detection and various risk factors in repeat saturation biopsies. A retrospective analysis was conducted on 78 Japanese patients for whom findings had caused suspicion of PCa despite previous negative prostate biopsies, and who consecutively underwent a 24-core transperineal repeat biopsy at Toyama University Hospital (Toyama, Japan). PCa was confirmed histologically in 16 of the 78 patients (20.5%). A univariate analysis revealed that the prostate-specific antigen (PSA) level at repeat biopsy was higher (P<0.01), the fPSA/tPSA ratio was lower (P=0.04), the total prostate volume was smaller (P=0.01) and the PSA density was higher (P<0.01) in PCa patients than in patients with benign prostatic disease (BPD). Histological inflammation was more frequently observed in BPD patients than in PCa patients (P<0.01). A multivariate analysis revealed that histological inflammation was the only independent predictor of the presence of a malignant lesion on repeat biopsy (odds ratio, 0.027; P=0.01). It must be considered that inflammation may cause a PSA increase in some patients with a negative initial biopsy, leading to unnecessary repeat biopsy.

7.
ACS Appl Mater Interfaces ; 8(7): 4803-10, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26862987

RESUMO

Developing a design strategy to establish the compatibility of acceptor materials with donor materials is important for the rational development of organic solar cells. We synthesized 2,6-dimethoxyphenyl methanofullerene derivatives to realize an enhanced open-circuit voltage, and we investigated polarities and their effects on the film morphology of the active layer. The polarities of the synthesized fullerene derivatives were affected significantly by the presence of functional groups, such as methoxy, ether, and ester groups. Macro/nanoscopic morphological investigation and spectroscopic analysis of the blend films of the poly(3-hexylthiophene)(P3HT)/fullerene derivatives showed that a balanced polarity between materials results in the formation of optimized nanomorphology without grains and robust phase separation. Measurements of the device performance of the photovoltaic cells composed of P3HT and the fullerene derivatives confirmed the same tendency as that shown in the morphological analysis. This finding enables us to obtain an improved power conversion efficiency because of the enhanced open circuit voltage derived from the fullerene derivatives.

8.
Int J Urol ; 20(2): 185-92, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22905941

RESUMO

OBJECTIVES: To evaluate the early quality of life outcomes in prostate cancer patients managed by high-dose-rate brachytherapy as monotherapy. METHODS: A total of 51 patients with cT1c-T3aN0M0 prostate cancer treated between July 2007 and January 2010 were included in this study. The average age was 69 years, and the average initial serum prostate-specific antigen was 10.98 ng/mL. A total of 25, 18 and eight patients were considered to be low, intermediate and high risk, respectively. All patients received one implant of Ir-192 and seven fractions of 6.5 Gy within 3.5 days for a total prescribed dose of 45.5 Gy. For high-risk prostate cancer, neoadjuvant androgen deprivation therapy was carried out for at least 6 months, and continued after high-dose-rate brachytherapy. Quality of life outcomes were measured by using the International Prostate Symptom Score, the Functional Assessment of Cancer Therapy-Prostate and the International Index of Erectile Function Questionnaire. The oncological outcome was assessed by serum prostate-specific antigen and diagnostic imaging. Adverse events were also recorded. RESULTS: The Functional Assessment of Cancer Therapy-Prostate scores decreased for a few months after high-dose-rate brachytherapy, and recovered to pretreatment condition thereafter. The International Prostate Symptom Score significantly increased 2 weeks after treatment for each of its items and their sum, and it returned to baseline after 12 weeks. Sexual function decreased at 2 and 4 weeks, and recovered after 12 weeks. Severe complications were rare. Within a median follow up of 17.2 months, two patients showed a prostate-specific antigen recurrence. CONCLUSIONS: High-dose-rate brachytherapy for prostate cancer is a feasible treatment modality with acceptable toxicity and only a limited impact on the quality of life.


Assuntos
Adenocarcinoma/radioterapia , Braquiterapia/métodos , Neoplasias da Próstata/radioterapia , Qualidade de Vida , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Fatores Etários , Idoso , Braquiterapia/efeitos adversos , Estudos de Coortes , Relação Dose-Resposta à Radiação , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Prognóstico , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica , Estudos Retrospectivos , Medição de Risco , Perfil de Impacto da Doença , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
9.
J Org Chem ; 77(20): 9038-43, 2012 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-23034001

RESUMO

A series of arylated dihydrofullerene derivatives were synthesized to elucidate the effective design of fullerene derivatives for enhancing the performance of organic photovoltaics. The LUMO energy of the fullerenes was estimated by the first reduction potential and theoretical calculations. The results showed that the methoxy groups substituted at spatial proximity to the fullerene core offered significant stabilization of the LUMO level. The stabilizing effect of the directly arylated fullerenes is more significant than that of conventional methanofullerenes. The theoretical investigation was performed with regard to the electronic interaction between the methoxy and fullerene moieties.

10.
J Laparoendosc Adv Surg Tech A ; 21(7): 629-33, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21745100

RESUMO

INTRODUCTION: A retroperitoneoscopic nephrectomy (RN) for symptomatic hydronephrosis (SH) is a challenging procedure because of the limited working space. This report describes a specific technical modification for efficient and successful RN for SH by using the SAND balloon catheter. PATIENT AND METHODS: A 38-year-old woman underwent RN for SH caused by extrinsic compression of the ureter by a pelvic endometriosis. The SAND balloon catheter was directly inserted into the expanded hydronephrotic sac, and the liquid was extracted, appropriately. Urine leakage from the hydronephrotic sac could be avoided because the puncture site was sealed firmly between the two adjacent balloons at the tip of the catheter. Disposal counter traction using the catheter facilitated the mobilization of the hydronephrotic sac. RESULTS: The patient was discharged 3 days after undergoing this procedure. CONCLUSIONS: This method improves the surgeon's vision and facilitates resection without causing any injury to the hydronephrotic sac wall during RN.


Assuntos
Cateterismo/instrumentação , Hidronefrose/cirurgia , Laparoscopia/métodos , Nefrectomia/métodos , Adulto , Catéteres , Desenho de Equipamento , Feminino , Humanos , Hidronefrose/diagnóstico , Espaço Retroperitoneal
11.
J Laparoendosc Adv Surg Tech A ; 20(10): 821-4, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21105768

RESUMO

BACKGROUND: Recent reports on laparoscopic surgery for urachal anomalies have not described any techniques to restore the natural appearance of the umbilicus. In this report, we present a simple technique that enables complete resection of urachal anomalies while preserving the natural appearance of the umbilicus. MATERIALS AND METHODS: Laparoscopic excision of symptomatic urachal anomalies was performed for 4 men and 2 women. After dissecting the urachal lesion along the preperitoneal plane toward the umbilicus, the cephalic side of the lesion was ligated and the skin at the base of the umbilicus was divided while compressing the anterior abdominal wall to ensure complete removal of the lesion. RESULTS: The laparoscopic procedure was successfully completed with minimal blood loss, and the umbilicus could be restored to its natural appearance in all the cases. CONCLUSIONS: This is the first report to describe a procedure for restoring the natural appearance of the umbilicus. This simple, alternative approach yields better cosmetic results and, therefore, will be useful, especially in younger patients.


Assuntos
Laparoscopia , Umbigo/cirurgia , Úraco/cirurgia , Adolescente , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , Estudos Retrospectivos , Técnicas de Sutura , Resultado do Tratamento , Umbigo/patologia , Úraco/patologia , Adulto Jovem
12.
J Laparoendosc Adv Surg Tech A ; 20(10): 843-6, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21029023

RESUMO

BACKGROUND: Laparoscopic surgery has not yet met with widespread acceptance due to its degree of technical difficulty. The laparoscopic radical nephrectomy procedure was improved with the aid of an abdominal wall sealing device, a wound retractor, and a surgical glove. METHODS: A 5 cm skin incision was made at the beginning of the operation. The Alexis wound retractor S was set up through this small incision. The wrist portion of the surgical glove (size 8-0) was then used to cover the outer ring of the wound retractor to maintain pneumoperitoneum. The surgeon can use most of the usual surgical instruments through the wound retractor during the laparoscopic surgery. RESULTS: These procedures were successfully conducted in all cases without open conversion, and no postoperative complications were observed. CONCLUSIONS: Glove-assisted laparoscopic surgery can be used to perform advanced laparoscopic procedures. This new technique made laparoscopic abdominal surgery easier and safer for beginners in laparoscopic surgery and skilled surgeons in open surgery.


Assuntos
Carcinoma de Células Renais/cirurgia , Luvas Cirúrgicas , Neoplasias Renais/cirurgia , Laparoscopia/métodos , Nefrectomia/métodos , Adulto , Idoso , Carcinoma de Células Renais/patologia , Estudos de Coortes , Feminino , Humanos , Neoplasias Renais/patologia , Laparoscopia/instrumentação , Masculino , Pessoa de Meia-Idade , Nefrectomia/instrumentação , Resultado do Tratamento
13.
Phys Rev E Stat Nonlin Soft Matter Phys ; 79(5 Pt 1): 051120, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19518429

RESUMO

We introduce solvable stochastic dealer models, which can reproduce basic empirical laws of financial markets such as the power law of price change. Starting from the simplest model that is almost equivalent to a Poisson random noise generator, the model becomes fairly realistic by adding only two effects: the self-modulation of transaction intervals and a forecasting tendency, which uses a moving average of the latest market price changes. Based on the present microscopic model of markets, we find a quantitative relation with market potential forces, which have recently been discovered in the study of market price modeling based on random walks.

14.
Hinyokika Kiyo ; 54(3): 203-6, 2008 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-18411776

RESUMO

In 177 patients, we evaluated the efficacy of a portable 3-dimensional ultrasound scanning device (Bladder Scan BVI6100) in measurement for residual urine volume, compared with transabdominal ultrasound estimation, using values measured by urethral catheterization as actual values. A high correlation was demonstrated between values measured by BVI6100 and actual values. Error rates of the values measured by BVI6100 male mode, female mode and transabdominal ultrasound estimation to actual values were 42.7 +/- 32.6, 50.6 +/- 63.3 and 65.8 +/- 43.7%, respectively. The error rate of the values measured by BVI6100 female mode was significantly higher than that by BVI6100 male mode or transabdominal ultrasound estimation. Irrespective of patient sex, the error rate of the values measured by BVI6100 in male mode was significantly lower than that in female mode. Therefore, BVI6100 male mode was considered to be a useful alternative for measurement of residual urine with accuracy similar to that of transabdominal ultrasound estimation.


Assuntos
Retenção Urinária/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ultrassonografia/instrumentação
15.
Mol Cell Biochem ; 247(1-2): 75-82, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12841634

RESUMO

Thrombopoietin (TPO) is a hematopoietic cytokine that regulates megakaryocytosis and thrombocytosis by binding to its receptor (c-Mpl). The signaling pathways downstream of c-Mpl include the Ras/Raf/MAP kinase and JAK/STAT pathway and are transduced into the regulation of immediate early-, early- and delayed-response genes. How these genes couple c-Mpl activation to the biochemical machinery of cell growth and cell cycle progression in hematopoietic cells is still unclear. UT-7/TPO is a recently characterized TPO-dependent cell line. Using RNA fingerprinting with arbitrarily primed PCR (RAP-PCR) to identify the TPO-regulated genes in this cell line, we found that the mRNA expression of nucleolin was upregulated in the UT-7/TPO cells in response to TPO. Concomitantly, the TPO-stimulated cells expressed an increased amount of full length nucleolin as determined by immunoblot analysis. The TPO-induced upregulation of nucleolin mRNA was not inhibited by the MEK1/2 inhibitor PD98059, suggesting that ERK/MAPK activation is not necessary for elevation of nucleolin gene expression in response to TPO in UT-7/TPO. Nucleolin is a multifunctional nucleolar protein thought to be involved in many cellular processes, including ribosome biogenesis, the processing of ribosomal RNA (rRNA), mRNA stability, transcriptional regulation, and cell proliferation. Thus, these results indicate that the upregulation of nucleolin mRNA and protein may be important for the TPO-induced effects of hematopoietic cells.


Assuntos
Megacariócitos/citologia , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Trombopoetina/farmacologia , Regulação para Cima/efeitos dos fármacos , Sequência de Bases , Linhagem Celular , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Perfilação da Expressão Gênica/métodos , Megacariócitos/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Dados de Sequência Molecular , Fosfoproteínas/efeitos dos fármacos , Reação em Cadeia da Polimerase/métodos , RNA Mensageiro/efeitos dos fármacos , Proteínas de Ligação a RNA/efeitos dos fármacos , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Nucleolina
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