情報フィルタリングを用いた地域ポータルサイトの開発

本論文は，保守性，検索精度，迅速性，可用性に優れたポータルサイトの開発に関する論文である．近年，地方自治体の経営資源の制約から，公共サービスを含む様々な分野のサービスを，近隣の地域間で分担補完するための連携が進められている．ゆえに，地域の情報を発信するポータルサイトにおいても，自治体の枠にとらわれない横断的なコンテンツを提供すべきである．しかしながら，このようなポータルサイトは現状なく，その実現が急務である．そこで本論文では，横断的なコンテンツを提供するポータルサイトを開発し，地方自治体間の連携の推進に寄与することを目的としたポータルサイトの実現方法を提案する．　本論文は全7章からなる．第1章では，地域ポータルサイトの現状について，地方自治体間の連携の観点から言及する．地方自治体間の連携が社会的に一般化しつつあるため，連携に対応した横断的なポータルサイトの実現が急務であることを述べる．続いて第2章では，地域のものづくりを中心とした産業振興を担う公共機関に焦点を当て，そのポータルサイトを紹介し，地域ポータルサイトの現状と課題を具体的に掘り下げる．既存のポータルサイトは，保守性，検索精度，迅速性の面で劣ることを述べるとともに，それらを向上させることが，地方自治体間の連携の推進につながることを示す．　第3章では，本論文の核である，情報フィルタリングを基盤としたポータルサイトの開発について述べる．ここでは，Webクローラによる保守性の向上策，URL フィルタによる検索精度の向上策，RSSパーサによる迅速性の向上策について述べる．開発したポータルサイトの特徴は，Webクローラの内部に情報フィルタリング機能を有している点である．Webクローラは，各地域情報が掲載されたWeb サイトを巡回し，ポータルサイトの情報を自動で更新するプログラムである．この機能によって，掲載情報の保守性を向上させる．また，このWebクローラ内部の情報フィルタリング機能は，WebページのURLから必要なWebページのみを選別する機能である．この機能によって，検索機能の精度を向上させる．RSSパーサは，Webサイトが配信するRSSを解析し，それをポータルサイトに反映させるプログラムである．この機能によって，新着情報のみを選別した上でポータルサイト上に掲載するとともに，Webクローラの実行のトリガーとすることで，情報発信の迅速性を向上させる．これらの機能を組み合わせることで，保守性，検索精度，迅速性に優れた，地域横断的なポータルサイトを実現する．　第4章から第6章では，開発したポータルサイトの社会実装と評価実験について述べる．まず第4章では，地域の産業を対象とした社会実装と評価実験について述べ，開発したポータルサイトが保守性，検索精度，迅速性の面で優れていることを定量的に示す．次に第5章では，第4章で社会実装を行ったポータルサイトの拡張と検索精度の向上策について述べる．ポータルサイトの拡張にともなう検索精度の低下に対する対策として，単語リストのパターンマッチングを提案する．この機能をWebクローラに組み込むことで，拡張前と同等の保守性，検索精度，迅速性を維持したまま拡張できることを示す．さらに第6章では，観光業を対象とした社会実装と評価実験について述べ，開発したポータルサイトが保守性，検索精度，迅速性の面で優れているとともに，外国人観光客にとっての可用性向上に資することを示す．　最後に第7章では，本論文で開発したポータルサイトによって，産業や観光業における地方自治体間の連携の推進に寄与したことを述べるとともに，今後の研究課題について言及する．電気通信大学201

Influence of Exercise History on the Proximal Femur Strength; Finite Element Analysis of Female Athletes

Bone structure and material properties adapt to mechanical loading, and accordingly exercise highly influences bone’s functional adaptation. Studying bones from various athletic subjects provides us a good opportunity to understand the mechanism of exercise-induced structural change in bone. Constructing 3D bone models has become available with current medical imaging techniques and is essential to investigate this mechanism. Finite element (FE) models of these bone models enable us to solve complicated numerical problems. In bone biomechanics, they provide an appropriate tool for assessing bone strength, detection of hip fracture prone regions and revealing the beneficial type of exercises to strengthen those regions. Hip fracture is a worldwide medical problem and majority of them are directly caused by falling. Cortical wall of the femoral neck get thinner with aging and some regions become more prone to the fracture. Impact loading exercises have positive effect on maintaining and/or increasing cortical thickness, increasing thus bone strength. This adaptation may be a key in preventing hip fractures. Therefore, the objective of this thesis was to investigate if the exercise history is associated with femoral neck bone strength in a lateral fall condition. To achieve this, MRI-based FE models of 36 young competitive female athletes’ proximal femurs were created. These subjects were categorized into 5 different groups based on the exercise history; 1) High-Impact, 2) Odd-Impact, 3) High-Magnitude, 4) Repetitive Low-Impact, 5) Repetitive Non-Impact, and compared to a control group. The proximal femur was modeled as the linear elastic, isotropic and homogenous material. Regional mean cortical and trabecular vonMises stresses were calculated for 8 anatomical sectors of the smallest cross-section of the femoral neck. Statistical analysis based on the nonparametric Mann-Whitney text was performed to investigate the difference in the sector-wise stress between each athlete’s group and the control group. At superior cortical region, ~17MPa stress was observed in the Odd-Impact group compared to ~20MPa stress in the control group. This result indicates that the proximal femur in the Odd-Impact groups has somewhat higher load bearing capacity in the lateral fall. Thus, Odd-Impact exercise performed in adulthood could be an optimal means to prevent bone fragility in older age. However, statistical power was very low and the findings from this study are preliminary and indicative only. Future study should include not only more subjects to obtain better statistical confidence, but also be based on more realistic the FE models and different loading conditions, including the dynamic situation

Exercise and Proximal Femur Bone Strength to Reduce Fall-Induced Hip Fracture

Bone mass and structure, constituting its strength, adapt to prevalent mechanical environment. Physical activity and exercise provide natural ways to apply the mechanical loading to bone. Finding effective osteogenic exercise types to improve proximal femur bone strength is of great importance to reduce hip fracture incidence and consequent substantial socioeconomic burden. Importantly, almost all hip fractures are caused by falls. Therefore, the primary objective of the present doctoral research was to find such effective exercise types by exploring the effect of long-term specific exercise loading on proximal femur bone strength in the fall situation using a finite element (FE) method. The secondary objective was to analyze 3D morphological adaptation of proximal femur cortical bone to the specific exercise loading. The results from this secondary objective were anticipated to help understanding the findings pertinent to the primary objective. To achieve these objectives, proximal femur MRI data were obtained from 91 young adult female athletes (aged 24.7 ± 6.1 years, > 8 years competing career) and 20 nonathletic but physically active controls (aged 23.7 ± 3.8 years). The athletes were classified into five distinct exercise loading groups based on the typical loading patterns of their sports: high-impact (H-I: triple- and high-jumpers), odd-impact (O-I: soccer/football and squash players), high-magnitude (H-M: powerlifters), repetitive-impact (R-I: endurance runners), and repetitive non-impact (R-NI: swimmers). Based on their MRI data, proximal femur FE models were first created in a single fall configuration (direction) to compare 1) cortical stresses in eight anatomical octants of femoral neck cross-sections in the proximal, middle, and distal femoral neck regions and 2) fracture behavior (load, location, and mode) between each exercise loading and control groups. The athletic bones are adapted to the long- term specific exercise loading characterized by not only the loading magnitude, rate, and frequency but also direction. Given this, the study was extended to simulate the FE models in multiple fall directions to examine whether potentially identified higher proximal femur bone strength to reduce fall-induced hip fracture risk, attributed to the long-term specific exercise loading, depends on the direction of the fall onto the greater trochanter or hip. For the secondary objective, a new computational anatomy method called Ricci-flow conformal mapping (RCM) was implemented to obtain 3D distribution of the cortical thickness within the proximal femur and to perform its spatial between-group statistical comparisons. Key results from the present research demonstrated that young adult females with the exercise loading history of high ground impacts (H-I), ground impacts from unusual/odd directions (O-I), or a great number of repetitive ground impacts (R-I) had 10-22%, 12-16%, and 14-23% lower fall-induced cortical stress at the fracture-prone superolateral femoral neck and 11-17%, 10-11%, and 22-28% higher fracture loads (higher proximal femur bone strength) in the fall situations compared to the controls, respectively. These results indicate that the long-term H-I, O-I, and R-I exercise loadings may reduce the fall-induced hip fracture risk. Furthermore, the present results showed that the higher proximal femur bone strength to reduce hip fracture risk in athletes engaged in the high-impact or repetitive-impact sports are robust and independent of the direction of fall. In contrast, the higher strength attributed to the odd-impact exercise loading appears more modest and specific to the fall direction. The analysis of the minimum fall strength spanning the multiple fall directions also supported the higher proximal femur bone strength in the athletes engaged in these impact exercises. In concordance with the literature, the present results also confirmed in these young adult females that 1) the fall-induced hip fracture most likely initiates from the superolateral femoral neck’s cortical bone, particularly at its posterior aspect (superoposterior cortex) in the distal femoral neck region, and 2) the most dangerous fracture-causing fall direction is the one where the impact is imposed to the posterolateral aspect of the greater trochanter. It would be ideal if impact exercise loading could induce beneficial cortical bone adaptation in the fracture-prone posterior aspect of superolateral femoral neck cortex. However, such apparently beneficial cortical adaptation was not observed in any of the impact or nonimpact exercise loading types examined in the present research based on the supplementary RCM-based 3D morphological analyses of proximal femur cortical bone. This analysis importantly showed that the higher proximal femur bone strengths to reduce fall-induced hip fracture risk in athletes engaged in the high- or odd-impact exercise types are likely due to thicker cortical layers in other femoral neck regions including the inferior, posterior, and/or superior-to-superoanterior regions. Interestingly, the higher proximal femur strength in the athletes with the repetitive-impact exercise loading was not supported by such cortical adaptation. This suggests that other structural/geometrical adaptation contributes to their higher strength. This calls for further studies to elucidate the source of the higher proximal femur bone strength in this type of athletes. In contrast to the impact exercise loading histories, the exercise loading history of the high-magnitude (e.g., powerlifting) or repetitive, non-impact (e.g., swimming) was not associated with higher proximal femur bone strength to reduce fall-induced hip fracture risk. This most likely reflects the lack of any beneficial structural adaptations of cortical bone around the femoral neck in the athletes with these exercise loading histories. Considering the loading characteristics of the exercise types examined in the present doctoral research, the moderate-to-high loading magnitude alone appears insufficient but needs to be generated at the high loading rate and/or frequency to induce the beneficial adaptation in the proximal femur cortical bone. Therefore, in addition to aforementioned three impact exercise loading types, other exercise or sport types satisfying this condition may also be effective to increase or maintain the proximal femur bone strength to reduce fall- induced hip fracture risk. As a clinical prospect, the present findings highlight the importance of impact exercise in combating fall-induced hip fracture. Compared to the high-impact loading exercises (e.g., triple/long and high jumping exercise), the odd-impact [ball or invasion games (e.g., football/soccer, tennis)] and/or repetitive-impact loading exercises (e.g., endurance running, jogging, and perhaps vigorous walking) likely provide a safer and more feasible choice for the populations covering the sedentary adults to old people. This is due to the relatively more moderate ground impact involved in the odd- and repetitive-impact loading exercises than in the high-impact exercises. For young, physically active, and/or fit people, the above-mentioned or similar jumping exercises and any other exercise types consisting of the high ground impact (e.g., volleyball, basketball, gymnastics) can also be incorporated into their habitual exercise routines. Lastly, the present results were observed in the young adult females who had engaged in sport-specific training from their childhood/adolescence to early adulthood. Therefore, this calls for the prospective and/or retrospective observational studies to investigate whether the higher proximal femur bone strength to reduce fall-induced hip fracture risk obtained from the long-term specific impact exercise loading during these early phases of life can sustain into the later stages, especially after age of 65 years when the hip fracture is generally more common

Does the three site Higgsless model survive the electroweak precision tests at loop?

We complete the list of one loop renormalization group equations and matching conditions relevant for the computation of the electroweak precision parameters $S$ and $T$ in the three site Higgsless model. We obtain one-loop formulas for $S$ and $T$ expressed in terms of physical observables such as the KK gauge boson mass $M_{W'}$, the KK fermion mass $M$, and the KK gauge boson ($W'$) couplings with light quarks and leptons $g_{W'ff}$. It is shown that these physical observables, $M_{W'}$, $M$ and $g_{W'ff}$ are severely constrained by the electroweak precision data. Unlike the tree level analysis on the ideally delocalized fermion, we find that perfect fermiophobity of $W'$ is ruled out by the precision data. We also study the cutoff dependence of our analysis. Although the model is non-renormalizable, the dependence on the cutoff parameter $\Lambda$ is shown to be non-significant.Comment: 13pages, 5figures, minor corrections made, references adde

Control of immunity and allergy by steroid hormones

Steroid hormones, especially glucocorticoids, androgens, and estrogens, have profound influence on immunity. Recent studies using cell-type specific steroid hormone receptor-deficient mice have revealed the precise roles of some of these hormones in the immune system. Glucocorticoids are known to have strong anti-inflammatory and immunosuppressive effects and pleiotropic effects on innate and adaptive immune responses. They suppress the production of inflammatory cytokines by macrophages and DCs and the production of IFN-γ by NK cells, thus inhibiting innate immunity. By contrast, glucocorticoids enhance the immune response by inducing the expression of IL-7R and CXCR4 in T cells and the accumulation of T cells in lymphoid organs in accordance with the diurnal change of the glucocorticoid concentration. Thus, glucocorticoids suppress innate immunity but enhance adaptive immunity. Androgens suppress the homeostasis and activation of ILC2s and the differentiation of Th2 and Th17 cells and enhance the suppressive function of Tregs, thereby alleviating allergic airway inflammation. Thus, these steroid hormones have pleiotropic functions in the immune system. Further investigations are awaited on the regulation of immunity and allergy by estrogens using cell-specific steroid hormone receptor-deficient mice

Z to b bbar and Chiral Currents in Higgsless Models

In this note we compute the flavor-dependent chiral-logarithmic corrections to the decay Z to b bbar in the three site Higgsless model. We compute these corrections diagrammatically in the "gaugeless" limit in which the electroweak couplings vanish. We also compute the chiral-logarithmic corrections to the decay Z to b bbar using an RGE analysis in effective field theory, and show that the results agree. In the process of this computation, we compute the form of the chiral current in the gaugeless limit of the three-site model, and consider the generalization to the N-site case. We elucidate the Ward-Takahashi identities which underlie the gaugeless limit calculation in the three-site model, and describe how the result for the Z to b bbar amplitude is obtained in unitary gauge in the full theory. We find that the phenomenological constraints on the three-site Higgsless model arising from measurements of Z to b bbar are relatively mild, requiring only that the heavy Dirac fermion be heavier than 1 TeV or so, and are satisfied automatically in the range of parameters allowed by other precision electroweak data.Comment: 19 pages, 7 embedded eps figures (additional reference added

JOINT ANGLE CHANGES WITH VARIED FOOT POSITIONING IN ROCK CLIMBING

high-step on a vertical indoor wall using different foot positions 1) with the inside edge of the foot or 2) with the front part of the shoe/toe against the wall. Subjects self-selected the rate of movement and specific body positioning, other than the right foot, during each trial. Reflective markers identified elbow, shoulder hip, knee, and ankle joints. Minimum and maximum joint angles were found via 3D kinematic analysis. With the exception of the elbow, Maximum joint angles were different between the two foot positions, however, there were no differences in the Minimal angles for any of the studied joints. Results indicate that when foot position is altered the climber adjusts maximum angles of other joints to perform the movement