Cascade radical cyclizations of benzannulated enyne-allenes and development of new synthetic strategies for novel polycyclic aromatic compounds

The cascade radical cyclization of benzannulated enyne-allene generated in situ from enediynyl propargylic alcohols promoted by thionyl chloride via an SNi\u27 reaction provides an efficient synthetic pathway to 11H-benzo[b]fluoren-11-ols and related compounds. The simplicity of the synthetic sequence and the mildness of the reaction condition make this cascade reaction sequence useful for the construction of polycyclic aromatic compounds. Interestingly, when this strategy was employed for the systems having two benzannulated enyne-allene units, it was quite unexpected that the reaction sequence led to the formation of highly twisted 1,1\u27-dialkyl-9,9\u27-bifluorenylidenes involving an unusual cleavage of a benzene ring, and spiro[1H-cyclobut[ a]indene-1,9\u27-[9H]fluorenes] along with other polycyclic aromatic compounds. Conceivably, the transformation from the precursors having two benzannulated enyne-allene units to the novel polycyclic compounds involves a C2-C6 cyclization reaction followed by a radical-radical coupling reaction and a tautomerization to give the formal Diels-Alder adducts or the [2+2] cycloaddition adducts.;The Ireland-Claisen rearrangement of the benzannulated enediynyl propargylic acetates was successfully adopted for the synthesis of the corresponding benzannulated enyne-allenes in situ for the subsequent Schmittel cyclization to generate benzofulvene biradicals for cascade radical cyclizations. The mildness of the reaction conditions and the ready availability of a variety of silyl ketene acetal make this synthetic pathway quite attractive. Several polycyclic aromatic derivatives of benzo[ghi]fluoranthene and 11H-benzo[ b]fluorene were thus produced from the corresponding enediynyl propargylic acetates in a single operation.;The Wagner-Meerwein rearrangement of fluorenylmethanols derived from 15,16-diaryl-diindeno[2,1-b:1\u27,2 \u27-h]phenanthrenes was successfully adopted for the synthesis of helical 17,18-diaryl-dibenzo[a,o]pentaphenes involving the carbocation-promoted ring expansion and aromatization. Two of the 17,18-diaryl-dibenzo[a,o]pentaphenes were employed for the subsequent intramolecular Friedel-Crafts arylation reactions involving phenyl or 4-biphenylyl substiuents at the 17 & 18 positions, producing several butterfly-shaped compounds having two planes of symmetry and a C2 symmetry in the case of the phenyl substituent and having only a C2 symmetry in the case of the 4-biphenylyl substituent. They possess very interesting structural features

Global conservative solutions of a generalized two-component Camassa-Holm system

The Cauchy problem for a generalized two-component Camassa-Holm system is investigated. Following the idea of fixed points and using new sets of independent and dependent variables, the existence of the global conservative solutions for the system is established

ANALYTICAL SOLUTION AND FIELD TEST OF CRITICAL BEARING CAPACITY AND SETTLEMENT OF PILE TIP

In order to explore the relationship between the critical bearing capacity and settlement of closed pile tip pierced into the soil, based on the Boussinesq solution and the Kelvin solution, the analytical solution between the critical bearing capacity and the critical settlement of the closed pile tip is derived by combining the stress distribution function. The analytical solution of critical bearing capacity and settlement of pile tip is verified by field test of static pressure pile penetrating into layered soil with a full-section pressure sensor installed at pile tip. The results show that during the penetration process, the bearing capacity increase stage of the pile tip is divided into linear steepening section and nonlinear slow increasing section. The soil in the linear steep increase section behaves as an elastic state. The bearing capacity of the pile tip before the punctured soil layer is linear with the settlement, and the final value of the linear steep increase section is the elastic limit value and the critical bearing capacity of the piercing pile tip. When the residual pile tip force is not considered, the critical settlement of the pile tip is between 0.095-0.119d; when considering the residual pile tip force, the critical settlement is between 0.091-0.105d. In particular, when the Poisson's ratio is 0.5, the analytical solution of the semi-infinite space is equivalent to the analytical solution of the infinite space

A Novel Adaptive Spectrum Noise Cancellation Approach for Enhancing Heartbeat Rate Monitoring in a Wearable Device

This paper presents a novel approach, Adaptive Spectrum Noise Cancellation (ASNC), for motion artifacts removal in Photoplethysmography (PPG) signals measured by an optical biosensor to obtain clean PPG waveforms for heartbeat rate calculation. One challenge faced by this optical sensing method is the inevitable noise induced by movement when the user is in motion, especially when the motion frequency is very close to the target heartbeat rate. The proposed ASNC utilizes the onboard accelerometer and gyroscope sensors to detect and remove the artifacts adaptively, thus obtaining accurate heartbeat rate measurement while in motion. The ASNC algorithm makes use of a commonly accepted spectrum analysis approaches in medical digital signal processing, discrete cosine transform, to carry out frequency domain analysis. Results obtained by the proposed ASNC have been compared to the classic algorithms, the adaptive threshold peak detection and adaptive noise cancellation. The mean (standard deviation) absolute error and mean relative error of heartbeat rate calculated by ASNC is 0.33 (0.57) beats·min-1 and 0.65%, by adaptive threshold peak detection algorithm is 2.29 (2.21) beats·min-1 and 8.38%, by adaptive noise cancellation algorithm is 1.70 (1.50) beats·min-1 and 2.02%. While all algorithms performed well with both simulated PPG data and clean PPG data collected from our Verity device in situations free of motion artifacts, ASNC provided better accuracy when motion artifacts increase, especially when motion frequency is very close to the heartbeat rate

Gaze-Informed egocentric action recognition for memory aid systems

Egocentric action recognition has been intensively studied in the fields of computer vision and clinical science with applications in pervasive health-care. The majority of the existing egocentric action recognition techniques utilize the features extracted from either the entire contents or the regions of interest in video frames as the inputs of action classifiers. The former might suffer from moving backgrounds or irrelevant foregrounds usually associated with egocentric action videos, while the latter may be impaired by the mismatch between the calculated and the ground truth regions of interest. This paper proposes a new gaze-informed feature extraction approach, by which the features are extracted from the regions around the gaze points and thus representing the genuine regions of interest from a first person of view. The activity of daily life can then be classified based only on the identified regions using the extracted gaze-informed features. The proposed approach has been further applied to a memory support system for people with poor memory, such as those with Amnesia or dementia, and their carers. The experimental results demonstrate the efficacy of the proposed approach in egocentric action recognition and thus the potential of the memory support tool in health care

A Regularized Gradient Projection Method for the Minimization Problem

We investigate the following regularized gradient projection algorithm xn+1=Pc(I−γn(∇f+αnI))xn, n≥0. Under some different control conditions, we prove that this gradient projection algorithm strongly converges to the minimum norm solution of the minimization problem minx∈Cf(x)

酸化ストレス下におけるヘムオキシゲナーゼ-1の尿細管上皮細胞における選択的細胞保護作用

取得学位 : 博士（医学）, 学位授与番号 : 医博甲第1615号, 学位授与年月日 : 平成16年3月25日, 学位授与大学 : 金沢大