Putting aromatic compounds to work: Rational synthesis of organic 2D polymers

This contribution describes two different approaches aimed at the synthesis of monolayer molecular sheets with internal order, or, in other words, 2D polymers. First, an interfacial strategy is presented in which terpyridene-based hexafunctional monomers spread at the air/water interface are connected to one another with the help of metal salts. While this approach leads to micrometer-sized monolayer sheets that are mechanically stable enough to be spanned over several micrometer-sized holes, their internal structure could not yet be proven. The second approach rests upon solid-state photochemistry, and properly designed monomers are covalently connected with one another while being held in layered geometries owing to crystal packing. Exfoliation to single sheets can be achieved, and molecular structure is supported by a Raman spectroscopic analysis. We consider this the first case of a rational synthesis of 2D polymers and briefly touch on the impact this may hav

Prediction of the Fracture Location by Tensile Tests of Gray Cast Iron Based on the Dimensional Changes of Graphite Flakes

Gray cast iron has been used as a component in various mechanical parts, such as the blocks and heads of automobile and marine engines, cylinder liners for internal combustion engines, and machine tool bases. It is desirable because of its good castability and machinability, damping characteristics, and high performance-to-cost ratio. On the other hand, weak graphite flakes present in gray cast iron serve as stress concentrators and adversely affect the material strength. Therefore, it is crucial to examine the relationship between the distribution of graphite flakes and the strength or fracture of gray cast iron. In this study, tensile tests on gray cast iron were carried out using a plate specimen and observed by scanning electron microscopy, and the microscopic deformation was observed on the specimen surface. Particularly, the change in the size of graphite flakes during the tensile tests was examined, and the observed trend was discussed. The experimental results reveal that the dimensional changes in the graphite flakes vary in the observed area and that the final fracture occurs in an area where a large dimensional change is observed, suggesting that the fracture location or critical parts of gray cast iron can be predicted from the dimensional changes of the graphite flakes at an early stage of deformation

シュトケン コンジュウ チイキ ニオケル ケイカンイキ ノ ケイカクテキ カダイ ト セイビ ニカンスル ケンキュウ

本研究は、本来、田園景観を呈する混在地域を、多様な機能を充足する居住地としての可能性を認め、それを活用するための条件を明確化しようとするものである。その1つの手がかりとして、混在化把握の新たな枠組みとしての景観に着目し、 ...筑波大学博士 (デザイン学) 学位論文・平成11年3月25日授与 (乙第1532号)標題紙，目次 -- Summary -- はじめに　 -- 本論文の概要 -- 第１章　研究の目的と方法 -- 第２章　首都圏における混住化動向に関する考察 -- 第３章　景観指標に基づく広域的地域類型と計画的課題 -- 第４章　混住地域における景観域の把握と類型化 -- 第５章　景観域における景観変容の特性 -- 第６章　景観域の計画論　ー計画的課題と整備の方向ー -- 資料編 -- 研究業績 -- 謝

Polymers Going Rigid, Thick, and Laterally Infinite

This short review article provides insight into the impact organic chemistry can have on state-of-the-art materials creation. Three cases were selected from the authors' laboratory, the first being 'Suzuki polycondensation', a powerful method with which innovative organic chemistry was successfully transferred to polymer synthesis and which meanwhile has even found technical scale application. The second describes the decoration of linear polymers with a dense layer of regular branch work. Though seemingly a rather esoteric enterprise, these decorations resulted in considerable property changes as compared to other linear polymers and, additionally, led to the discovery of novel properties. Consequently, this area which is commonly referred to as 'dendronized polymers' in a world-wide activity has been developed into a ripe research field, presently under exploration for possible technical application. Finally, an example still very much in its first tumbling steps was selected to give yet another perspective of the role of organic chemistry in a materials-oriented chemistry. It aims at the generation of ultrathin, yet internally strictly defined, sheet-like macromolecules for which a great future is foreseen, e.g. as a 2D platform for the systematic construction of 3D matter

Finite Element Study of the Effect of Internal Cracks on Surface Profile Change due to Low Loading of Turbine Blade

Turbine blades for thermal power plants are exposed to severe environments, making it necessary to ensure safety against damage, such as crack formation. A previous method detected internal cracks by applying a small load to a target member. Changes in the surface properties of the material were detected before and after the load using a digital holographic microscope and a digital height correlation method. In this study, this technique was applied in combination with finite element analysis using a 2D and 3D model simulating the turbine blades. Analysis clarified that the change in the surface properties under a small load varied according to the presence or absence of a crack, and elucidated the strain distribution that caused the difference in the change. In addition, analyses of the 2D model considering the material anisotropy and thermal barrier coating were conducted. The difference in the change in the surface properties and strain distribution according to the presence or absence of cracks was elucidated. The difference in the change in the top surface height distribution of the materials with and without a crack was directly proportional to the crack length. As the value was large with respect to the vertical resolution of 0.2 nm of the digital holographic microscope, the change could be detected by the microscope

Visualizing Individual Perceptual Differences Using Intuitive Word-Based Input

Numerous studies have investigated the fundamental dimensions of human tactile perceptual space using a wide range of materials. Participants generally touch materials and quantitatively evaluate variations in tactile sensations for pairs of adjectives pertaining to the material properties, such as smooth—rough and soft—hard. Thus, observers evaluate their perceptual experiences one by one in terms of adjective pairs. We previously proposed an alternative method of qualitative evaluation of tactile sensations. Our system can automatically estimate ratings of fundamental tactile properties from single sound-symbolic words. We were able to construct a word-based perceptual space by collecting words that express tactile sensations and applying them to the system. However, to explore individual differences in perceptual spaces, different databases for converting words into ratings of adjective pairs are required for each individual. To address this, in the present study we created an application that can automatically generate an individualized perceptual space by moving only a few words in the initial word-based perceptual space. In addition, we evaluated the efficacy of the application by comparing the tactile perceptual space before and after use

Generalized edema and heart failure caused from hypothyroidism and ferrous agent for hypochromic anemia

The patient was an 85-year-old female who has been treated for hypertension and atrial fibrillation (Af). She has visited outpatient clinic and has received regularly general blood tests for every six months. Hemoglobin (Hb) level was stable as 11.2-12.3 g/dL and MCV 88fL from 2017, but it decreased suddenly to 5.2 g/dL and 64 fL in Sept 2020. She did not feel any symptoms or signs. Further evaluations revealed that occult blood in stool and upper and endoscopic exams were negative. About 40 days after starting sodium ferrous citrate, she developed edema anasarca, bilateral pleural effusion and heart failure. Laboratory test showed hypothyroidism, and then the administration of thyroid hormone and diuretics brought her early improvement. As to this impressive case report, general clinical progress and some discussion of the relationship among anemia, edema anasarca, heart failure and hypothyroidism would be described

cis9, trans11-Conjugated Linoleic Acid Differentiates Mouse 3T3-L1 Preadipocytes into Mature Small Adipocytes through Induction of Peroxisome Proliferator-activated Receptor γ

Dietary conjugated linoleic acid (CLA) has been reported to exhibit a number of therapeutic effects in animal models and patients, such as anti-hypertensive, anti-hyperlipidemic, anti-arteriosclerotic, anti-carcinogenic, and anti-diabetic effects. However, the underlying mechanism is not well-characterized. In the present study, the effects of cis(c)9, trans(t)11-CLA on the differentiation of mouse 3T3-L1 preadipocytes into mature adipocytes were examined. Treatment with c9, t11-CLA in the presence of insulin, dexamethasone, and 3-isobutyl-1-methyl-xanthine (differentiation cocktail) significantly stimulated the accumulation of triacylglycerol. The microscopic observation of cells stained by Oil Red O demonstrated that c9, t11-CLA increases the amount and proportion of small mature adipocytes secreting adiponectin, a benign adipocytokine, when compared to the differentiation cocktail alone. Furthermore, c9, t11-CLA increased bioactive peroxisome proliferator-activated receptor γ (PPARγ) levels in a nuclear extract of 3T3-L1 cells, suggesting the enhancing effect of this fatty acid on the nuclear transmission of PPARγ, a master regulator of adipocyte differentiation, in 3T3-L1 cells. These results suggest that the therapeutic effects of c9, t11-CLA on lifestyle-related diseases are partially due to the enhanced formation of small adipocytes from preadipocytes via PPARγ stimulation

Prediction Models for BMI and NAFLD

Nonalcoholic fatty liver disease (NAFLD) is closely associated with obesity. Disulfide bond‐forming oxidoreductase A‐like protein (DsbA‐L) is known to be a key molecule in protection against obesity and obesity‐induced inflammation. In the present study, we used a modeling and simulation approach in an attempt to develop body mass index (BMI) and BMI‐based NAFLD prediction models incorporating the DsbA‐L polymorphism to predict the BMI and NAFLD in 341 elderly subjects. A nonlinear mixed‐effect model best represented the sigmoidal relationship between the BMI and the logit function of the probability of NAFLD prevalence. The final models for BMI and NAFLD showed that DsbA‐L rs1917760 polymorphism, age, and gender were associated with the BMI, whereas gender, patatin‐like phospholipase 3 rs738409 polymorphism, HbA1c, and high‐density and low‐density lipoprotein cholesterol levels were associated with the risk of NAFLD. This information may aid in the genetic‐based prevention of obesity and NAFLD in the general elderly population

Current Multidisciplinary Approach to Fertility Preservation for Breast Cancer Patients

Adverse effects on fertility are a significant problem for premenopausal breast cancer patients. Since April 2009, we have been referring young patients for fertility counseling provided by a multidisciplinary team. Here we evaluated the efficacy and safety of our current fertility preservation approach. We retrospectively analyzed the cases of 277 patients < 45 years old at diagnosis, which was made between 2009 and 2016. Seventy-two (26%) patients received fertility counseling. Seventeen (6%) of the 277 patients decided to preserve their fertility before starting adjuvant systemic therapy. Six (35%) patients underwent oocyte cryopreservation, and 11 (65%) married patients opted for embryo cryopreservation. There were no pregnancies among the patients undergoing oocyte cryopreservation, whereas 3 (27%) of the patients who opted for embryo cryopreservation became pregnant. Two (12%) patients stopped endocrine therapy after 2 years in an effort to become pregnant, but their breast cancers recurred. Though the problem of fertility loss for breast cancer patients is important and we should assess the infertility risk for all patients, we should also consider the prognosis. In June 2016, we launched a prospective multicenter cohort study to evaluate the efficacy and safety of fertility preservation in greater detail