Immediate versus water-storage performance of Class V flowable composite restoratives

Objectives The aims of this investigation were to clarify the effects of 24 h water-storage and finishing time on mechanical properties and marginal adaptation to a Class V cavity of eight modern flowable resin-composites. Methods Eight flowable composites, plus two controls (one microfilled and one hybrid composite), were investigated with specimen sub-groups (n = 10) for each property measured. The principal series of experiments was conducted in model Class V cavities with interfacial polishing either immediately (3 min) after setting or after 24 h water-storage. After the finishing procedure, each tooth was sectioned in a buccolingual direction through the center of the restoration, and the presence or absence of marginal-gaps was measured (and then summed for each cavity) at 14 points (each 0.5 mm apart) along the cavity restoration interface (n = 10 per group; total points measured = 140). The shear bond-strengths to enamel and to dentin, and flexural strengths and moduli data were also measured at 3 min and after 24 h water-storage. Results For all flowable composites, polished immediately after setting, 14–30 summed gaps were observed (controls: 64 and 42). For specimens polished after 24 h, a significantly (p &#60; 0.05) reduced number of 8–17 summed gaps occurred for only 3 flowable composites; whereas for 5 flowable composites there were non-significantly-different (p &#62; 0.05) numbers (11–17) of summed gaps (controls: 28 and 22). After 24 h storage, shear bond-strengths to enamel and to dentin, flexural strengths and moduli increased highly significantly (p &#60; 0.001) for all materials, except Silux Plus. Significance A post-cure interval of 24 h resulted in enhanced mechanical and adhesive properties of flowable dental composites. In a minority of cases there was also a reduced incidence of marginal-gap formation. However the latter effect may be partly attributed to 24 h delayed polishing, even though such a delay is not usual clinical practice.</p

Filtering effect of cone oil droplets detected in the P-111 response spectra of japanese quail

AbstractWhile absorption spectra of bird cone visual pigments have been well studied, physiological study of bird cone cells has been less advanced owing to their small sizes. We measured the P-III components of electroretinograms (ERG) from isolated retinas of Japanese quail. We recorded responses to monochromatic flashes of equal photon numbers, and found that the shape of the response spectrum is dependent on the incident direction of the flashes. The spectrum obtained with the flashes from the cornea side had a steeper peak around 500 nm than that with flashes from the receptor side. This is clear electrophysiological evidence of the filtering effect of the oil droplets in the cone cells, which has long been suspected. We analyzed these spectra with respect to the absorption spectra of cone pigments and transmittance spectra of oil droplets

Noise-limited scene-change detection in images

This thesis describes the theoretical, experimental, and practical aspects of a noise-limited method for scene-change detection in images. The research is divided into three sections: noise analysis and modelling, dual illumination scene-change modelling, and integration of noise into the scene-change model. The sources of noise within commercially available digital cameras are described, with a new model for image noise derived for charge-coupled device (CCD) cameras. The model is validated experimentally through the development of techniques that allow the individual noise components to be measured from the analysis of output images alone. A generic model for complementary metal-oxide-semiconductor (CMOS) cameras is also derived. Methods for the analysis of spatial (inter-pixel) and temporal (intra-pixel) noise are developed. These are used subsequently to investigate the effects of environmental temperature on camera noise. Based on the cameras tested, the results show that the CCD camera noise response to variation in environmental temperature is complex whereas the CMOS camera response simply increases monotonically. A new concept for scene-change detection is proposed based upon a dual illumination concept where both direct and ambient illumination sources are present in an environment, such as that which occurs in natural outdoor scenes with direct sunlight and ambient skylight. The transition of pixel colour from the combined direct and ambient illuminants to the ambient illuminant only is modelled. A method for shadow-free scene-change is then developed that predicts a pixel's colour when the area in the scene is subjected to ambient illumination only, allowing pixel change to be distinguished as either being due to a cast shadow or due to a genuine change in the scene. Experiments on images captured in controlled lighting demonstrate 91% of scene-change and 83% of cast shadows are correctly determined from analysis of pixel colour change alone. A statistical method for detecting shadow-free scene-change is developed. This is achieved by bounding the dual illumination model by the confidence interval associated with the pixel's noise. Three benefits arise from the integration of noise into the scene-change detection method: - The necessity for pre-filtering images for noise is removed; - All empirical thresholds are removed; and - Performance is improved. The noise-limited scene-change detection algorithm correctly classifies 93% of scene-change and 87% of cast shadows from pixel colour change alone. When simple post-analysis size-filtering is applied both these figures increase to 95%

The spectroscopic impedance of cellophane

Paper presented at the Fifth International Conference on Electromagnetic Wave Interaction with Water and Moist Substances, 2003, Rotorua, N. Z.The electrical impedance of cellophane has been measured as a function of moisture content and temperature in the frequency range 10⁻³ – 10⁵ Hz. The data show a very strong dependence on moisture content, which is a typical characteristic of hygroscopic solids, and at low frequencies, remarkable constant phase angle spectra were obtained. Making use of the hopping model of conduction in non-crystalline solids, we explain the measured spectra. The model treats absorbed water as an impurity in the cellophane and conduction is predicted to occur by temperature-activated proton hopping between water molecules. We also propose that this model is widely applicable to prediction of the low frequency dielectric properties of hygroscopic solids

Development of Interactive Learning Material for Internal Stress of a Bending Beam

　材料力学は工学初心者にとって理解が容易な分野であるとは言い難い。例えば，中学校技術科教員を目指す学生で，片持ちはりに力を加えた場合にどのような内部応力が発生するのか正しく理解しているものは少ない。本研究では，仮想空間に呈示された片持ちはりに対して，学習者が三次元力覚呈示装置を介して接触し，自ら力を加えて変形させたときの内部応力分布を視覚的に確認できる教材を開発した。内部応力の算出には有限要素法の弾性二次元解析を用いた。自然な力覚呈示には1ms以下の周期が必要とされるが，有限要素法は要素数（節点数）とともに計算時間が増加する。本研究では要素数（節点数）と計算時間の関係を明らかにした上で，力覚呈示の条件を満たす仕様を決定した。結果として十分な分解能を持つ分割要素を組み込んだ教材においても，要求される計算速度を達成できることが確認された

Induction of Ptp2 and Cmp2 protein phosphatases is crucial for the adaptive response to ER stress in Saccharomyces cerevisiae

Expression control of the protein phosphatase is critically involved in crosstalk and feedback of the cellular signaling. In the budding yeast ER stress response, multiple signaling pathways are activated and play key roles in adaptive reactions. However, it remains unclear how the expression level of the protein phosphatase is modulated during ER stress response. Here, we show that ER stress increases expression of Ptp2 tyrosine phosphatase and Cmp2 calcineurin phosphatase. Upregulation of Ptp2 is due to transcriptional activation mediated by Mpk1 MAP kinase and Rlm1 transcription factor. This induction is important for Ptp2 to effectively downregulate the activity of Hog1 MAP kinase. The budding yeast genome possesses two genes, CMP2 and CNA1, encoding the catalytic subunit of calcineurin phosphatase. CMP2 is more important than CNA1 not only in ER stress response, but also in salt stress response. Higher promoter activity of CMP2 contributes to its relative functional significance in ER stress response, but is less important for salt stress response. Thus, our results suggest that expression control of Ptp2 and Cmp2 protein phosphatases at the promoter level is crucial for adaptive responses to ER stress

ＲＮＡ制御系によるｍＲＮＡ安定性と翻訳の時空間ファインチューニング

科学研究費助成事業 研究成果報告書：基盤研究(C)2015-2017課題番号 : 15K0694

Gene Expression Profiles of the Small Intestinal Mucosa of Dogs Repeatedly Infected with the Cestode \u3ci\u3eEchinococcus multilocularis\u3c/i\u3e

The data set presented in this article is related to a previous research article entitled, The timing of worm exclusion in dogs repeatedly infected with the cestode Echinococcus multilocularis (Kouguchi et al., 2016). This article describes the genes \u3e2 fold up- or down-regulated in the first- and repeated-infection groups compared to the healthy controls group. The gene expression profiles were generated using the Agilent-021193 Canine (V2) Gene Expression Microarray (GPL15379). The raw and normalized microarray data have been deposited with the Gene Expression Omnibus (GEO) database under accession number GSE105098