Semismall perturbations, semi-intrinsic ultracontractivity, and integral representations of nonnegative solutions for parabolic equations

We consider nonnegative solutions of a parabolic equation in a cylinder D \timesI, where $D$ is a noncompact domain of a Riemannian manifold and $I =(0,T)$ with $0 < T \le \infty$ or $I=(-\infty,0)$. Under the assumption [SSP] (i.e., the constant function 1 is a semismall perturbation of the associated elliptic operator on $D$), we establish an integral representation theorem of nonnegative solutions: In the case $I =(0,T)$, any nonnegative solution is represented uniquely by an integral on $(D \times \{0 \}) \cup (\partial_M D \times [0,T))$, where $\partial_M D$ is the Martin boundary of $D$ for the elliptic operator; and in the case $I=(-\infty,0)$, any nonnegative solution is represented uniquely by the sum of an integral on $\partial_M D \times (-\infty,0)$ and a constant multiple of a particular solution. We also show that [SSP] implies the condition [SIU] (i.e., the associated heat kernel is semi-intrinsically ultracontractive).Comment: 35 page

Differential localization of the centromere-specific proteins in the major centromeric satellite of Arabidopsis thaliana

The 180 bp family of tandem repetitive sequences, which constitutes the major centromeric satellite in Arabidopsis thaliana, is thought to play important roles in kinetochore assembly. To assess the centromere activities of the 180 bp repeats, we performed indirect fluorescence immunolabeling with antibodies against phosphorylated histone H3 at Serl0, HTR12 (Arabidopsis centromeric histone H3 variant) and AtCENP-C (Arabidopsis CENP-C homologue) for the A. thaliana cell cultures. The immunosignals from all three antibodies appeared on all sites of the 180 bp,repeats detected by fluorescence in situ hybridization. However, some of the 180 bp repeat clusters, particularly those that were long or stretched at interphase, were not fully covered with the signals from anti-HTR12 or AtCENP-C. Chromatin fiber immunolabeling clearly revealed that the centromeric proteins examined in this study, localize only at the knobs on the extended chromatin fibers, which form a limited part of the 180 bp clusters. Furthermore, outer HTR12 and inner phosphohistone H3 (Ser1O) localization at the kinetochores of metaphase chromosomes suggests that two kinds of histone H3 (a centromere variant and a phosphorylated form) might be linked to different roles in centromere functionality; the former for spindle-fiber attachment, and the latter for chromatid cohesion.</p

ライムギ小型染色体を保持する普通系コムギからのライムギ型cDNAのディファレンシャルスクリーニング

Occurrence of the midget chromosome in a common wheat with rye cytoplasm [(cereale)-Chinese Spring (CS)] indicates that the chromosome carries the essential gene(s) for maintaining the function of rye cytoplasm. To elucidate the interaction between the midget chromosome and rye cytoplasm, in this study, an attempt was made to isolate rye-type cDNAs from a cDNA library of (cereale)-CS by differential screening. Two replica filters from each plate were hybridized with digoxigenin (DIG)-labeled wheat CS cDNAs and with DIG-labeled rye cDNAs,respectively. Out of ca. 20,000 plaques, 27 were hybridized more strongly with rye cDNAs than with CS cDNAs. These clones were classified into six classes (Ⅰ-Ⅵ) by blot hybridization. The majority of the clones (21 out of 27) was belonged to the same class (1), showing rye-type RFLP (restriction fragment length polymorphism). The DNA sequence of clone CrClA in class Ⅰ, was very similar to that of wheat ribulose 1,5-bisphosphate carboxylase,large subnit gene, rbcL(94.5% homology). However, the 3' end of CrClA was shorter than that of wheat rbcL, and terminated at TAA instead of TAG, like the rbcL of Aegilops crassa. In the clone CrC5.4, the first half of the sequence was similar to that of one rice EST clone, the functions of which are not known, and the latter was similar to the reverse sequence of maize 4.5S-23S ribosomal RNA. This suggests that CrC5.4 had been derived from two defferent cDNAs of (cereale)-CS. Three other clones had homology to the chlorophyll a/b binding protein genes (cab) of wheat, maize and tomato, and one to wheat rbcS (ribulose1,5-bisphosphate carboxylase small subnit gene). However, no clear polymorphisms were detected between wheat and rye by using those clones as probes.ライムギの細胞質を有する普通系コムギ(cereale)-Chinese Spring (CS)には、「ミジェット」と呼ばれる非常に小型の染色体が存在する。この染色体が失われると、その種子は胚乳が退化して発芽出来ない。かりに発芽しても、その植物は虚弱で不稔となる。このことは、この染色体にライムギ細胞質の機能維持に不可欠な遺伝子が座乗していることを示唆している。本研究では、ディファレンシャルスクリーニング法により、このミジェット染色体に座乗している遺伝子の同定を試みた。(cereale)-CSの若苗からcDNAライブラリーを作成し、約20,000のプラークをスクリーニングした。その結果、ライムギのcDNAには強くハイブリダイズするが、CSのcDNAには弱くハイブリダイズするクローンが27得られた。これらについてその特異性をサザンハイブリダイゼイション等で解析したところ、19個のクローン( CrClAなど) はサイズ、制限酵素部位に違いは認められるもののお互いにハイブリダイズすることから、同じクラスⅠに分類された。これらは、正常CSと(cereale)-CSとの間でRELP（制限酵素断片長多型）を示し、その型はライムギと同様であった。このcDNAの塩基配列は、コムギ葉緑体DNA遺伝子rbcLに類似しており、ライムギの葉緑体DNAに由来していると考えられた。他のクローンは、コムギの核遺伝子cabとrbcにその塩基配列が類似していたが、はっきりとした多型は検出されなかった。ここで用いた方法では、光合成に関連した発現量の多いcDNAがスクリーニングされやすい傾向があり、効率的なスクリーニングには均一化したcDNAを用いる必要があると思われる

Sakurajima-Satsuma (Sz-S) and Noike-Yumugi (N-Ym) tephras: new tephrochronological marker beds for the last deglaciation, southern Kyushu, Japan

Two prominent tephras, Sakurajima-Satsuma (Sz-S) erupted from Sakurajima volcano and Noike-Yumugi (N-Ym) erupted from Kuchierabujima Island, provide new key marker beds for dating and synchronizing palaeoenvironmental and archaeological records in the last deglaciation in southern Japan. These tephras were identified on the basis of glass major-element compositions in two distal areas, a marine core (IMAGES MD98-2195) in the northern part of the East China Sea and on the central part of Tanegashima Island, and related their stratigraphic positions to the marine oxygen isotope-based chronology. In MD98-2195, Sz-S, 0.8 cm in thickness at 9.12 m depth and N-Ym, 3 cm in thickness at 9.30 m depth, are both white, vitric, ash-grade tephras. On Tanegashima Island, Sz-S, 10 cm in thickness and N-Ym, 3 cm in thickness, are stratigraphically constrained by well-characterised marker tephras Kikai-Akahoya (7,300 cal BP) and Aira-Tn (29,000 cal BP). Sz-S is rhyolitic and homogeneous on the basis of glass major-element compositions assayed by electron microprobe. Pumiceous glass shards predominant in distal Sz-S tephra indicate that it derived from pumice fall units that correspond to pumiceous and phreatomagmatic fine ash units constituting proximal Sz-S tephra. N-Ym is rhyolitic and glass major-element analyses reveal compositional diversity between units, suggesting that the lower and middle tephra units dispersed to the east, whereas the upper unit was dispersed north to north-west from the vent. Stratigraphically, Sz-S occurs at around the start of the late-glacial reversal (cooling) in oxygen isotope records of MD98-2195, corresponding to the end of GI-1 and the start of GS-1 in the ice-core events of NGRIP (GICC05), consistent with a terrestrial age of ˜12,800 cal BP. Based on the oxygen isotope stratigraphy, the tephra identified in the core as N-Ym at 9.30 m depth is close to the end of Greenland GI-1 and hence has an age of ˜13,000 cal BP, but on Kuchierabujima Island it has an age based on ¹⁴C assay of charcoal of c. 14,900 cal BP. Although this age discrepancy (14.9 vs 13.0 cal ka) needs resolution, the occurrence in core MD98-2195 of N-Ym shows that it is more widespread than hitherto demonstrated. The widespread distributions and key stratigraphic positions for the two marker tephras indicate that they are thus critical isochrons for precise correlation of palaeoenvironmental changes and prehistoric cultural events during the last deglaciation in southern Kyushu, and for relating such changes and events to the ice-core chronology via the marine oxygen isotope chronostratigraphy

Compulsory Repetitive Learning to Improve Student Achievement and Performance in Fundamental Subjects

　We employ the methodology of “Compulsory Repetitive Learning” to improve student learning and performance in fundamental subjects. It is a challenge for many universities to intrinsically motivate students and it is a demanding issue that a large part of students do not sufficiently do homework. Here, we let students solve the problems associated with the teaching immediately following each lecture. Through the usage of “Compulsory Repetitive Learning”, each student as well as the subject teacher(s) could monitor and evaluate the quality of student learning and performance

General Architecture for Hardware Implementation of Genetic Algorithm

FCCM 2006 : 14th Annual IEEE Symposium on Field-Programmable Custom Computing Machines , Apr 24-26, 2006 , Napa, CA, USAIn this paper, the authors propose a technique to flexibly implement genetic algorithms (GAs) for various problems on FPGAs. For the purpose, the authors propose a common architecture for GA. The proposed architecture allows designers to easily implement a GA as a hardware circuit consisting of parallel pipelines which execute GA operations. The proposed architecture is scalable to increase the number of parallel pipelines. The architecture is applicable to various problems and allows designers to estimate the size of resulting circuits. The authors give a model for predicting the size of resulting circuits from given parameters. Based on the proposed method, the authors have implemented a tool to facilitate GA circuit design and development. Through experiments using knapsack problem and traveling salesman problem (TSP), the authors show that the FPGA circuits synthesized based on the proposed method run much faster and consume much lower power than software implementation on a PC and the model can predict the size of the resulting circuit accurately enough

Congestion Alleviation Scheduling Technique for Car Drivers Based on Prediction of Future Congestion on Roads and Spots

ITSC2007 : IEEE Intelligent Transportation Systems Conference , Sep 30-Oct 3, 2007 , Bellevue, WA, USAIn arranging efficient touring to various areas in urban areas, taking into account potential congestion is needed in order to schedule the order of these visits it is important to on the roads used and at the places to be visited. A number of scheduling methods have been proposed for finding (1) a noncongested route by sharing route information among users, or (2) a schedule to alleviate congestion at specific places based on the latest congestion information. However, these methods do not suffice since they do not deal with, simultaneously, congestion on road and at sites visited. In this paper, we propose a method of finding schedules for thousands of users by predicting, in advance, both types of congestion. Using the predicted results, the method adjusts each user's provisional schedule by changing visiting order of places, and reducing their number in keeping with each user's preferences. We have implemented the proposed method and evaluated it by simulations. The results showed it to achieve higher user satisfaction than existing methods

A Hardware Implementation Method of Multi-Objective Genetic Algorithms

CEC2006 : IEEE International Conference on Evolutionary Computation , Jul 16-21, 2006 , Vancouver, BC, CanadaMulti-objective genetic algorithms (MOGAs) are approximation techniques to solve multi-objective optimization problems. Since MOGAs search a wide variety of pareto optimal solutions at the same time, MOGAs require large computation power. In order to solve practical sizes of the multi objective optimization problems, it is desirable to design and develop a hardware implementation method for MOGAs with high search efficiency and calculation speed. In this paper, we propose a new method to easily implement MOGAs as high performance hardware circuits. In the proposed method, we adopt simple Minimal Generation Gap (MGG) model as the generation model, because it is easy to be pipelined. In order to preserve diversity of individuals, we need a special selection mechanism such as the niching method which takes large computation time to repeatedly compare superiority among all individuals in the population. In the proposed method, we developed a new selection mechanism which greatly reduces the number of comparisons among individuals, keeping diversity of individuals. Our method also includes a parallel execution architecture based on Island GA which is scalable to the number of concurrent pipelines and effective to keep diversity of individuals. We applied our method to multi-objective Knapsack Problem. As a result, we confirmed that our method has higher search efficiency than existing method

A personal tourism navigation system to support traveling multiple destinations with time restrictions

AINA2004 : The 18th International Conference on Advanced Information Networking and Applications , Mar 29 -31, 2004 , Fukuoka, JapanWe propose a personal navigation system (called PNS) which navigates a tourist through multiple destinations efficiently. In our PNS, a tourist can specify multiple destinations with desired arrival/stay time and preference degree. The system calculates the route including part of the destinations satisfying tourist's requirements and navigates him/her. For the above route search problem, we have developed an efficient route search algorithm using a genetic algorithm. We have designed and implemented the PNS as a client-server system so that the portable device users can use the PNS through the Internet. Experiments using general map data and PDAs show that our PNS can calculate a semioptimal route almost in real-time

Video ads dissemination through WiFi-cellular hybrid networks

PerCom2009 : The Seventh Annual IEEE International Conference on Pervasive Computing and Communications , Mar 16-20, 2009 , Dallas, TX, USAIn this paper, we propose a method for video ads dissemination through a hybrid network consisting of WiFi and cellular networks, in order to provide timely delivery of video ads with preferred content to users according to the users' contexts. In recent years, video download/streaming services for cellular phones have already become popular. Among various video delivery services, a service for disseminating video ads according to the users' contexts is expected to achieve high advertising effects. However, context-aware video ads dissemination will consume large bandwidth since the size of video ad is rather large and the same ad is required at different time from various users. We propose a new video ads dissemination method for mobile terminals which utilizes both WiFi and cellular networks. In the proposed method, a file of video ad is divided into pieces and each node exchanges the pieces with neighbor nodes using WiFi ad hoc communication so that the usage of cellular network is reduced. In order to make the method works effectively for a large number of nodes, we propose an algorithm where mobile nodes autonomously and probabilistically decide their actions without a central control. Through simulations, we confirmed that our method reduces cellular network usage by about 93% compared with a case that all nodes download video ads via cellular network, and works effectively in cases with a large number of nodes and high mobility