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Fluorescence-guided surgery using 5-aminolevulinic acid (5-ALA) is now a widely-used modality for glioblastoma (GBM) treatment. However, intratumoral heterogeneity of fluorescence intensity may reflect different onco-metabolic programs. Here, we investigated the metabolic mechanism underlying the heterogeneity of 5-ALA fluorescence in GBM. Using an in-house developed fluorescence quantification system for tumor tissues, we collected 3 types of GBM tissues on the basis of their fluorescence intensity, which was characterized as strong, weak, and none. Expression profiling by RNA-sequencing revealed 77 genes with a proportional relationship and 509 genes with an inverse relationship between gene expression and fluorescence intensity. Functional analysis and in vitro experiments confirmed glutaminase 2 (GLS2) as a key gene associated with the fluorescence heterogeneity. Subsequent metabolite profiling discovered that insufficient NADPH due to GLS2 underexpression was responsible for the delayed metabolism of 5-ALA and accumulation of protoporphyrin IX (PpIX) in the high fluorescence area. The expression level of GLS2 and related NADPH production capacity is associated with the regional heterogeneity of 5-ALA fluorescence in GBM.

Background To evaluate the clinical impact of fluorescence-guided surgery (FGS) in glioblastoma, we analyzed the clinical data of 80 consecutive patients operated on by a single surgeon with or without 5-aminolevulinic acid (5-ALA). Methods We compared 3-dimensional volumetric extent of resection and clinical outcomes between 40 consecutive patients undergoing resection using a white-light (WL) microscope and 40 subsequent consecutive patients undergoing resection using FGS with 5ALA. Results By introducing FGS, there was a significant difference in the mean volumetric extent of the resection rate of T1-enhancing lesions (84.7% in the white-light group and 97.0% in the 5-ALA group, P = .002). The complete resection rate was improved from 43% to 80%, and the proportion of resections that were Conclusions The present study adds practical evidence of the clinical impact of 5-ALA FGS on glioblastomas from the surgeon's standpoint.

With the advent of the Internet, the types and amount of information one can access have increased dramatically. In today's overwhelming information environment, recommendation systems that quickly analyze large amounts of available information and help users find items of interest are increasingly needed. This paper proposes an improvement of an existing preference prediction algorithm to increase the accuracy of recommendation systems. In a recommendation system, prediction of items preferred by users is based on their ratings. However, individual users with the same degree of satisfaction to an item may give different ratings to the item. We intend to make more precise preference prediction by perceiving differences in users' rating dispositions. The proposed method consists of two processes of perceiving users' rating dispositions with clustering and of performing rating normalization according to such rating dispositions. The experimental results show that our method yields higher performance than ordinary collaborative filtering approach.

Background: Supratentorial primitive neuroectodermal tumors (PNETs) are highly malignant and rare tumors of the central nervous system. Objectives: The aim of this study was to determine the role of Gamma Knife surgery (GKS) as a salvage treatment option for patients with recurrent or residual supratentorial PNETs. Methods: Between 1998 and 2014, 11 patients with supratentorial PNETs were retrospectively analyzed. This series consisted of 7 male and 4 female patients. The median age was 17 years. All patients received surgical resection followed by adjuvant therapy. The median time from operation to the first GKS treatment was 72.5 months. The median tumor volume was 17.5 cm3, and the median marginal dose was 11.5 Gy. Results: 15 (65%) of the 23 tumors had been controlled. The actuarial local tumor control rate was 91% at 3 months, 73% at 6 months, and 44% at 12 months. At the time of analysis, 9 (82%) of the patients had died. The median survival time after the first GKS session was 17 months. The median survival time from the initial diagnosis was 65 months. No adverse radiation effect after GKS treatment occurred in any patient. Conclusions: GKS treatment might be an effective salvage treatment option for recurrent or residual supratentorial PNETs after multimodal treatment.

Total removal of petroclival meningioma is difficult, and aggressive extirpation is often associated with significant surgical morbidity and mortality. The aim of this study was to evaluate the long-term outcome and failure pattern of treatment with Gamma Knife radiosurgery (GKRS) in patients with petroclival meningiomas. Eighty-nine consecutive patients with petroclival meningiomas underwent GKRS between 1998 and 2013. Fifty-eight patients received GKRS as a primary treatment and 31 patients underwent GKRS as a secondary treatment after microsurgery. The mean tumor volume was 6.7 cm3 (range, 0.5-46.3 cm3) and the mean marginal dose was 13.2 Gy (range, 8-17 Gy). At the last radiological follow-up, tumor volume was decreased in 50 patients (56.2%), stationary in 34 patients (38.2%), and increased in 5 patients (5.6%). The actuarial progression-free survival after GKRS was 94.7% at 5 years and 88.9% at 10 years. Favorable cranial nerve outcomes were found in 81 patients (91%). A regrowth pattern was present in all 4 patients of the primary treatment group, whereas cyst formation (3 patients) and regrowth (1 patient) were observed in the secondary treatment group. GKRS is an effective and reasonable option as a primary or secondary treatment for petroclival meningioma. Further studies of failure patterns after GKRS for petroclival meningioma are mandatory.

OBJECTIVE Gamma Knife surgery (GKS) represents an alternative treatment for patients with tumor-related trigeminal neuralgia (TRTN). However, in previous studies, the primary GKS target was limited to mass lesions. The authors evaluated whether GKS could target both the tumor and the trigeminal root exit zone (REZ) in a single session while providing durable pain relief and minimizing radiation dose–related complications for TRTN patients. METHODS The authors' institutional review board approved the retrospective analysis of data from 15 consecutive patients (6 men and 9 women, median age 67 years, range 45–79 years) with TRTN who had undergone GKS. In all cases, the radiation was delivered in a single session targeting both the tumor and trigeminal REZ. The authors assessed the clinical outcomes, including the extent of pain relief, durability of the treatment response, and complications. Radiation doses to organs at risk (OARs), including the brainstem and the cranial nerve VII–VIII complex, were analyzed as doses received by 2% or 50% of the tissue volume and the tissue volume covered by a dose of 12 Gy (V12Gy). RESULTS The median length of clinical follow-up was 38 months (range 12–78 months). Pain relief with GKS was initially achieved in 14 patients (93.3%) and at the last follow-up in 13 patients (86.7%). The actuarial recurrence-free survival rates were 93%, 83%, and 69% at 1, 3, and 5 years after GKS, respectively. Persistent facial numbness was observed in 3 patients (20.0%). There were no complications such as facial weakness, altered taste function, hearing impairment, and balance difficulties indicating impaired function of the cranial nerve VII–VIII complex. The V12Gy in the brainstem was less than or equal to 0.24 cm3 in all patients. There were no significant differences in any OAR values in the brainstem between patients with and without facial numbness after GKS. CONCLUSIONS The strategy of performing GKS for both tumor and trigeminal REZ in a single session is a safe and effective radiosurgical approach that achieves durable pain control for TRTN patients.

SUMMARY Radio frequency identification (RFID), a new technology for the contactless recognition of objects, is considered an ideal solution to replace barcode systems. To make RFID technology widely applicable, it is important to resolve the ‘multiple tag identification problems’, that is, the problem of indicating tag collisions occurring when multiple RFID tags are simultaneously present in a reader's field. The proposed anti-collision algorithm in this paper consists of two separate phases: distribution and recognition. The algorithm distributes tags to be read in such a way that tag collisions are reduced. In the distribution phase, the conventional ALOHA algorithm is used with a newly added command. When there are several occurrences of collision or no-response in a round, a new round is initiated by adjusting the frame size on the basis of the estimated number of tags. ALOHA-based algorithms have the weakness of not being able to guarantee a 100% tag identification rate. Hence, the proposed algorithm uses a tree-based algorithm in the recognition phase in order to eliminate this problem. In addition, the reversed ID approach is employed to ensure efficient tag identification. The simulation results show that the proposed algorithm takes less tag identification time than the conventional algorithms, thereby increasing RFID system efficiency. Copyright © 2012 John Wiley & Sons, Ltd.

IPTV, a technological convergence that combines communication and broadcasting technologies, delivers customized, interactive TV content and other multimedia information over wired and wireless connections. Providing secure access to IPTV services calls for authentication, without proper and secure authentication mechanisms, an individual impersonating a subscriber could steal a service. This paper proposes a new authentication protocol to authenticate IPTV users. The authors based the proposed protocol, a hybrid authentication protocol providing lightweight, personalized user authentication, on RFID (radio-frequency identification) and USIM (Universal Subscriber Identity Module) technologies. In the proposed protocol, USIM performs highly personalized authentication, and the authenticated subscriber's RFID tags can have a temporary authority to execute authentication. These RFID tags become Agent Tags authorized to authenticate subscribers. Agent Tags identify and authenticate themselves to RFID readers in the set-top box, thus, simplifying the authentication process.

*Graduate School of Railroad, Seoul National University of Technology*Korea Railroad Research Institute(Received February 2, 2011; Revised March 12, 2011; Accepted March 13, 2011)Abstract − The brake disc materials for railway vehicle have been mainly used cast-iron. The brake disc and padshould be light, resist to a thermal crack and absorb enough friction energy. In order to satisfy this requirement,aluminum alloy brake disc for railway vehicle has been newly developed. The aluminum itself has not been con-sidered the friction material for railway vehicle. However, in the case of aluminum composite with dispersedceramic particles, friction characteristics, resistance to wear and heat are much improved. In the present study,aluminum composite brake disc of 20% ceramic particle and three kinds of organic pads have been tested indynamometer. The results show that Al MMC brake disc and pad have good friction coefficient and wear rate,and thermal cracks in brake disc have not been initiated. Also, the Al MMC brake disc can be applied to railwayvehicle of 150 km/h.Keywords − brake disc(제동디스크), brake lining(제동라이닝), friction coefficient(마찰계수), wear rate(마모량), Al brake disc(알루미늄 제동디스크), light weight(경량화)

Radio Frequency IDentification (RFID ) system is a contactless automatic identification system using small, low-cost RFID tags. It enables recognition of the tag information via radio frequency communication, by attaching an RFID tag to an animate or inanimate object. Since an RFID system has the advantage of simultaneously recognizing massive amounts of information, it is expected to replace the bar-code system. The most important problem with an RFID system is that an adversary can access the tag information, which gives rise to privacy and forgery problems. This paper presents a hash-based mutual authentication protocol as a solution. The proposed protocol is designed to send a random number generated by a tag to a back-end server without disclosure. Moreover it substitutes a random number with a secret value, which is employed in a response message. The properties of the proposed protocol enable constant creation of distinct response messages without interferences from intended or meaningless requests generated by an adversary, while the secret value is not directly transmitted. Our proposed protocol make is difficult for an attacker to launch successful brute-force attacks against our approach.

Let T be a tree in which every edge is associated with a real number. The sum of a path in T is the sum of the numbers associated with the edges of the path and its length is the number of the edges in it. For two positive integers L 1 ≤ L 2 and two real numbers S 1 ≤ S 2 , a path is feasible if its length is between L 1 and L 2 and its sum is between S 1 and S 2 . We address the problem: Given a tree T, and four numbers, L 1 , L 2 , S 1 and S 2 , find the longest feasible path of T. We provide an optimal O(n log n) time algorithm for the problem, where n = |T|.

In this study, we demonstrate complex networks of CD8 T cell cross-reactivities between influenza A virus and EBV in humans and between lymphocytic choriomeningitis virus and vaccinia virus in mice. We also show directly that cross-reactive T cells mediate protective heterologous immunity in mice. Subsets of T cell populations reactive with one epitope cross-reacted with either of several other epitopes encoded by the same or the heterologous virus. Human T cells specific to EBV-encoded BMLF1280–288 could be cross-reactive with two influenza A virus or two other EBV epitopes. Mouse T cells specific to the vaccinia virus-encoded a11r198–205 could be cross-reactive with three different lymphocytic choriomeningitis virus, one Pichinde virus, or one other vaccinia virus epitope. Patterns of cross-reactivity differed among individuals, reflecting the private specificities of the host’s immune repertoire and divergence in the abilities of T cell populations to mediate protective immunity. Defining such cross-reactive networks between commonly encountered human pathogens may facilitate the design of vaccines.

Background Tumors with cysts often correlate with gliomas, metastatic tumors, or hemangioblastomas, which require differentiation. Methods Thirty-eight cases of cyst associated-meningioma based on preoperative radiologic studies and histologic confirmations were reviewed from November 1998 to July 2017. Results A total of 395 cases of meningioma were observed in the 20 years, and surgical treatment of intracranial meningioma was performed in 120 cases. Thirty-eight (9.6%) cases of cyst associated meningiomas were analyzed. Nauta type I was the most common type of cyst (39.5%) and the most frequent histopathological subtype was meningothelial type (36.8%). Conclusion Statistically there were no significant associations between meningioma histopathological type and associated cysts; however, the rate of World Health Organization grade II was higher in cyst associated meningiomas than in unrelated meningiomas. This correlation was weak, in accordance with the meningioma grade.

Noble N-substituted-3-fluoropyrroles derivatives were prepared from new precursor via ring formation. The addition reaction of ethyl iododifluoroacetate to vinyl trimethylsilane under the Cu(0) catalyst resulted in the formation of ethyl-2,2-difluoro-4-iodo-4-(trimethylsilyl)butanolate, which reacted with diisobutylaluminium hydride at ‒30 o C to yield 2,2-diflouro-4-iodo-4-(trimethylsilyl)butanal. Finally, a series of N-substituted-3-fluoropyrrole derivatives were synthesized by the reaction of 2,2-diflouro-4-iodo-4-(trimethylsilyl)butanal with NH4OH or primary amines followed by reaction with KF solution.

In this paper, we address the following problems: Given a sequence A of n real numbers, and four parameters I, J, X and Y with I ≤ J and X ≤ Y, find the longest (or shortest) subsequence of A such that its length is between I and J and its sum is between X and Y. We present an online and an offline algorithm for the problems, both run in O(n log n) time, which are optimal.

Let T be a tree with n nodes, in which each edge is associated with a length and a weight. The density-constrained longest (heaviest) path problem is to find a path of T with maximum path length (weight) whose path density is bounded by an upper bound and a lower bound. The path density is the path weight divided by the path length. We show that both problems can be solved in optimal O(n log n) time.

Let T be a node-weighted tree with n nodes, and let π(u, v) denote the path between two nodes u and v in T. We address two problems: (i) Path Maximum Query: Preprocess T so that, for a query pair of nodes u and v, the maximum weight on π(u, v) can be found quickly. (ii) Path Maximum Sum Query: Preprocess T so that, for a query pair of nodes u and v, the maximum weight sum subpath of π(u, v) can be found quickly. For the problems we present solutions with O(1) query time and O(n log n) preprocessing time.

Radio Frequency Identification (RFID) Technology is a contactless automatic identification technology using radio frequency. For this RFID technology to be widely spread, the problem of privacy invasion should be solved. There are many research works in progress to solve the RFID privacy problems. Most of works for solving this problem have focused on developing light-weight cryptographic modules which can be embedded into RFID tags, but some of them used a proxy agent approach that control communications between the tag and the reader for protecting user privacy. The later approach is very useful and practical in terms of manufacturing low-cost tag hardware. However, all schemes of this approach have some problems in ownership transfer and forgery detection. In this paper, we are focusing on the proxy agent approach and we suggest an advanced agent scheme that guarantees not only privacy protection but also forgery detection. And our scheme is more scalable than other agent schemes so far.

We study the problem of finding the maximum suffix of a string on the external memory model of computation with one disk. In this model, we are primarily interested in designing algorithms that reduce the number of I/Os between the disk and the internal memory. A string of length  has  suffixes and among these, the lexicographically largest one is called the maximum suffix of the string. Finding the maximum suffix of a string plays a crucial role in solving some string problems. In this paper, we present an external memory algorithm for computing the maximum suffix of a string of length . The algorithm uses four blocks in the internal memory and performs at most 4 disk I/Os, where  is the size of a block.Keyword:External Memory Algorithms, Maximum Suffix, Strings 1. Introduction 1) Let ∑ be an alphabet. Let  and  be two strings over ∑. If s is lexicographically less than  , we denote this by  . Let     , where N is the length of  . For ≤≤≤ ,   

In a tree with each edge associated with a length and a weight (positive, negative, or zero are possible) we develop an O(nlognloglogn) time algorithm for finding a path such that its sum of weights is maximized and its sum of lengths does not exceed a given value. The previously best-known result is O(), where n is the number of nodes in the tree.

Background Nevus depigmentosus (ND) is known to be a rare congenital, nonprogressive disorder characterized by a hypopigmented lesion that remains stable over time. There have been only few studies of clinical and histopathologic characteristics of ND, and the etiopathogenesis is not fully established. Objective The purpose of this study was to investigate the clinical and histopathologic characteristics of ND. Methods A clinical survey was carried out with 60 patients given the diagnosis of ND. Punch biopsies (2 mm) from lesional and perilesional normal skin were performed. The sections were stained with hematoxylin-eosin, Fontana-Masson, antibodies to S-100 protein, MART-1, NKI/beteb, CD1a, CD3, CD20, and CD68. Results The lesions were usually present before the age of 3 years (68.3%), but some lesions appeared later in childhood (31.7%). In all, 27 patients (45%) had one lesion, but there were 14 patients (23.3%) who had more than 10 lesions. Fontana-Masson stain showed that the amount of melanin was significantly decreased in ND skin compared with perilesional normal skin. Melanocyte counts were significantly decreased in ND skin when stained with antibodies to GP-100 and MART-1. However, there were no significant differences in the number of melanocytes identified as S-100 protein–positive cells. There were no significant differences in histologic findings or dermal inflammatory infiltrates between ND skin and perilesional normal skin. Limitations Only 29 patients (48.3%) were followed up, and the average follow-up period after initial diagnosis was relatively short (68 months); therefore, these overall results may not be representative of the clinical course of the patients. Conclusion Only 18 patients (30.0%) presented with ND since birth and only 27 patients (45.0%) had one lesion. Both the amount of melanin and the number of melanocytes in ND skin were decreased in patients with ND. Therefore, both clinical and histologic findings should be considered together to make a diagnosis of ND.

Summary: The main functions of memory T cells are to provide protection upon re‐exposure to a pathogen and to prevent the re‐emergence of low‐grade persistent pathogens. Memory T cells achieve these functions through their high frequency and elevated activation state, which lead to rapid responses upon antigenic challenge. The significance and characteristics of memory CD8+ T cells in viral infections have been studied extensively. In many of these studies of T‐cell memory, experimental viral immunologists go to great lengths to assure that their animal colonies are free of endogenous pathogens in order to design reproducible experiments. These experimental results are then thought to provide the basis for our understanding of human immune responses to viruses. Although these findings can be enlightening, humans are not immunologically naïve, and they often have memory T‐cell populations that can cross‐react with and respond to a new infectious agent or cross‐react with allo‐antigens and influence the success of tissue transplantation. These cross‐reactive T cells can become activated and modulate the immune response and outcome of subsequent heterologous infections, a phenomenon we have termed heterologous immunity. These large memory populations are also accommodated into a finite immune system, requiring that the host makes room for each new population of memory cell. It appears that memory cells are part of a continually evolving interactive network, where with each new infection there is an alteration in the frequencies, distributions, and activities of memory cells generated in response to previous infections and allo‐antigens.

Why some virus-specific CD8 TCR repertoires are diverse and others restricted or "oligoclonal" has been unknown. We show here that oligoclonality and extreme clonal dominance can be a consequence of T cell cross-reactivity. Lymphocytic choriomeningitis virus (LCMV) and Pichinde virus (PV) encode NP(205-212) epitopes that induce different but highly cross-reactive diverse TCR repertoires. Homologous viral challenge of immune mice only slightly skewed the repertoire and enriched for predictable TCR motifs. However, heterologous viral challenge resulted in a narrow oligoclonal repertoire with dominant clones with unpredictable TCR sequences. This shift in clonal dominance varied with the private, i.e., unique, specificity of the host's TCR repertoire and was simulated using affinity-based computer models. The skewing differences in TCR repertoire following homologous versus heterologous challenge were observed within the same private immune system in mice adoptively reconstituted with memory CD8 T cell pools from the same donor. Conditions driving oligoclonality resulted in an LCMV epitope escape variant in vivo resembling the natural Lassa virus sequence. Thus, T cell oligoclonality, including extremes in clonal dominance, may be a consequence of heterologous immunity and lead to viral escape. This has implications for the design of peptide-based vaccines, which might unintentionally prime for skewed TCR responses to cross-reactive epitopes.

Recently the tagSNP selection problem has been researched for reducing the cost of association studies between human`s diversities and SNPs. General approach for this problem is that all of SNPs are separated into appropriate blocks and then tagSNPs are chosen in each block. Marsel in this paper is the system that involved the concept of linkage disequilibrium for overcoming the problem that the existing block partitioning approaches have short of biological meanings. In most approaches, the contiguous regions, which recombinations have LD coefficient |D`| and then tagSNP selection step is performed. and MarSel guarantees the minimum tagSNP selection using entropy-based optimal selection algorithm when tagSNPs are chosen in each block, and enables chromosome-level association studies using efficient memory management technique when input is very large-scale dataset that is impossible to be processed in the existing systems. Key Words: SNP,dynamic Programming,Haplotype,tagSNP Selection,Linkage Disequilibrium

Malignant glioma treated with anti-vascular endothelial growth factor (VEGF) bevacizumab show progression patterns that vary with different mechanisms of resistance. We evaluated the clinico-radiological data of 71 patients with progressive malignant glioma treated with bevacizumab to determine the prognostic value of the differential outcome of each progression pattern. Progression patterns were categorized as three types based on the initial response to bevacizumab and serious changes of MR images i.e., non-enhancing infiltration, flare-up of contrast enhancement (CE) and primary non-responder progression. We analyzed the clinical outcome in each type of progression using Kaplan–Meier survival analysis. Analysis of progression patterns showed that incidence of non-enhancing infiltration progression (28.1 %) was less common than flare-up of CE or primary non-responder pattern. The time from initiation of bevacizumab to development of non-enhancing infiltration or flare-up of CE progression was longer than for progression in primary non-responders. There was no significant difference of overall survival, progression-free survival from start of bevacizumab therapy, survival after bevacizumab failure between non-enhancing infiltration and flare-up of CE patterns. However, in the non-enhancing infiltration pattern, early appearance of enhancement was observed after bevacizumab was discontinued, resulting in poor survival, as compared to flare-up of CE pattern (P = 0.01). Although the appearance of non-enhancing infiltration after bevacizumab does not imply a worse prognosis, discontinuation of therapy can aggravate the clinical course.

A longest nonnegative path in an edge-weighted tree is a path such that the sum of edge weights on it is nonnegative and the number of edges on it is as large as possible. In this paper we show that if a tree has a constant degree, then its longest nonnegative path can be found in O(n log n) time, where n is the number of nodes. Previously known algorithms take O(n log2 n) time.

CD8 T cell cross-reactivity between viruses can play roles in protective heterologous immunity and damaging immunopathology. This cross-reactivity is sometimes predictable, such as between lymphocytic choriomeningitis virus (LCMV) and Pichinde virus, where cross-reactive epitopes share six out of eight amino acids. Here, however, we demonstrate more subtle and less predictable cross-reactivity between LCMV and the unrelated vaccinia virus (VV). Epitope-specific T cell receptor usage differed between individual LCMV-infected C57BL/6 mice, even though the mice had similar epitope-specific T cell hierarchies. LCMV-immune mice challenged with VV showed variations, albeit in a distinct hierarchy, in proliferative expansions of and down-regulation of IL-7Rα by T cells specific to different LCMV epitopes. T cell responses to a VV-encoded epitope that is cross-reactive with LCMV fluctuated greatly in VV-infected LCMV-immune mice. Adoptive transfers of splenocytes from individual LCMV-immune donors resulted in nearly identical VV-induced responses in each of several recipients, but responses differed depending on the donor. This indicates that the specificities of T cell responses that are not shared between individuals may influence cross-reactivity with other antigens and play roles in heterologous immunity upon encounter with another pathogen. This variability in cross-reactive T cell expansion that is unique to the individual may underlie variation in the pathogenesis of infectious diseases.

Virus-specific memory T cell populations demonstrate plasticity in antigen recognition and in their ability to accommodate new memory T cell populations. The degeneracy of T cell antigen recognition and the flexibility of diverse antigen-specific repertoires allow the host to respond to a multitude of pathogens while accommodating these numerous large memory pools in a finite immune system. These cross-reactive memory T cells can be employed in immune responses and mediate protective immunity, but they can also induce life-threatening immunopathology or impede transplantation tolerance and graft survival. Here we discuss examples of altered viral pathogenesis occurring as a consequence of heterologous T cell immunity and propose models for the maintenance of a dynamic pool of memory cells.

Viral infections have been shown to induce lymphopenias that lower memory CD8 T cell frequencies, and they also have been shown to cause a permanent loss of memory cells specific to previously encountered pathogens. In this study, the patterns and significance of virus-induced memory CD8 T cell depletion were examined in mice immune to heterologous (Pichinde, vesicular stomatitis, vaccinia) viruses and subsequently challenged with acute or persistent lymphocytic choriomeningitis virus infections. Memory CD8 T cell loss was comprehensive and occurred in both lymphoid and peripheral tissues of the immune host. The impact of the loss of memory T cells was reflected by in vivo cytotoxicity assays, which showed decreased clearance of epitope-expressing targets. Memory CD8 T cell loss occurred very early (day 2) after infection, and was thereafter sustained, consistent more with an active deletion model than with a competition model. Cross-reactive T cells, in contrast, increased in number, but memory cells were reduced whether or not there was competition from cross-reactive T cells. Memory T cell loss was more profound during persistent infection than after acute infection. Adoptive transfer studies showed that, unlike the resolved acute infection, in which the reduced memory frequencies became stable, memory T cell loss was a continuously ongoing process during persistent infection. This study therefore links an early virus-induced lymphopenia to a subsequent long-term loss of CD8 T cell memory and offers a new mechanism for immune deficiency during persistent viral infections.

Viruses can cause a severe lymphopenia early in infection and a subsequent, lasting loss of pre-existing CD8+ memory T cells. We therefore questioned how well virus Ag-specific memory CD8+ T cells could reconstitute mice rendered lymphopenic as a consequence of genetics, irradiation, or viral or poly(I:C)-induced cytokines. In each case, reconstitution of the CD8+ compartment was associated with limited division of virus-specific memory T cells and a reduction in their proportion. This indicates that foreign Ag-experienced CD44highCD8+ memory T cells may respond differently to homeostatic signals than other CD44highCD8+ cells, and that events inducing lymphopenia may lead to a permanent reduction in T cell memory.

The aim of this study was to evaluate the effectiveness of the extended endoscopic endonasal transsphenoidal approach (TSA) for recurrent or residual craniopharyngiomas, focusing on the extent of tumor resection and complications resulting from surgery at a single institution. Twelve adult patients (six men and six women) underwent extended endoscopic endonasal TSA for a recurrent or residual craniopharyngioma after a previous surgical intervention at a single institution by a single surgeon. The mean number of surgeries patients had undergone before TSA was 1.3 (range, 1–3). The mean period between patients’ most recent surgery and extended TSA was 55.9 months (range, 1–184). The mean preoperative (that is, pre-extended TSA) tumor volume was 2.87 cm³. The mean follow-up period was 15.8 months (range, 4–32). We reviewed clinical and radiological features in each case, focusing on the degree of tumor resection as well as endocrinological and ophthalmological outcomes. Gross total resection was achieved in ten patients (83.3 %), and the mean resection rate was 87 % in the other two cases. There were no significant differences between pre- and postoperative endocrine function, except in one patient who suffered postoperative panhypopituitarism resulting in pituitary stalk resection, which was necessary because of obvious tumor involvement. Three patients suffered transient diabetic insipidus (DI). With respect to ophthalmological outcomes, three patients showed improvement, two others showed decline, and the remainder showed no significant changes. The extended endoscopic endonasal transsphenoidal approach is an effective and safe surgical approach for treating recurrent or residual craniopharyngioma.

In the recommendation system suitable for products showing repetitive purchase pattern, we can use the repeat count of purchase for each product per user as a recommendation criteria. We implemented a system that recommends Products by user-based Collaborative Filtering and item-based Collaborative Filtering method, and recommends Associate Products analyzed by Association Rules.

Background Ischemia/reperfusion (I/R) injury in the early posttransplant period is closely associated with delayed recovery of graft function, increased acute rejection, and late allograft dysfunction. Pharmacological preconditioning with low-dose cyclosporine (CsA) or FK506 was performed to induce ischemic tolerance in rat kidney with I/R injury. Methods Low-dose CsA (3 mg/kg, administered i.v.) or FK506 (0.3 mg/kg i.v.) were used to induce ischemic tolerance in Sprague-Dawley rats, and the induction of heat shock protein (hsp) 70 by CsA or FK506 was evaluated overtime. Rats were pretreated with CsA or FK506 6 hr before I/R injury when hsp70 was maximally expressed, and were killed 24 hr later. The effect of pharmacological preconditioning on subsequent I/R injury was evaluated in terms of renal function, histopathology score, assays for apoptosis (DNA fragmentation analysis, TUNEL staining, expressions of pro-apoptotic genes, and caspase activity), and the expression of inflammatory cytokine genes (interleukin-1 and tumor necrosis factor-alpha). Results Preconditioning with low-dose CsA or FK506 significantly improved renal function and renal histology, compared to rats with I/R injury. Apoptotic cell death (typical DNA laddering and increased TUNEL-positive cells) in rat kidneys with I/R injury, was decreased by pretreatment with low-dose CsA or FK506. Increased expression of pro-apoptotic genes (Fas, Fas-ligand, caspase 1 and 3) and activated caspases in ischemic rat kidneys were decreased after CsA or FK506 pretreatment. Conclusions Pretreatment with low-dose CsA or FK506 prevents subsequent I/R injury, and this effect may be related to the induction of hsp70. Pretreatment of renal donors with low-dose CsA or FK506 may result in an improvement in immediate posttransplant function.

A rectilinear map consists of a set of mutually non-intersecting rectilinear (i.e., horizontal or vertical) line segments, and each segment is allowed to use a rectangular label of height B and length the same as the segment. Sliding labels are not restricted to any finite number of predefined positions but can slide and be placed at any position as long as it intersects the segment. This paper considers three versions of the problem of labeling a rectilinear map with sliding labels and presents efficient exact and approximation algorithms for them.

Let P and Q be disjoint polygons in the plane. We consider the problem of finding an optimal bridge (p,q) , p∈ \partial P and q∈ \partial Q , such that the length of the longest path from a point in P , passing through the bridge (p,q) , to a point Q is minimized. We propose efficient algorithms for three cases according to whether P and Q are convex or not. These problems are motivated from the bridge construction between two islands (or the canal construction between two lakes).

We investigate several straight-line drawing problems for bounded-degree trees in the integer grid without edge crossings under various types of drawings: (1) upward drawings whose edges are drawn as vertically monotone chains, a sequence of line segments, from a parent to its children, (2) order-preserving drawings which preserve the left-to-right order of the children of each vertex, and (3) orthogonal straight-line drawings in which each edge is represented as a single vertical or horizontal segment. Main contribution of this paper is a unified framework to reduce the upper bound on area for the straight-line drawing problems from O (n log n) (Crescenzi et al., 1992) to O (n loglog n) . This is the first solution of an open problem stated by Garg et al. (1993). We also show that any binary tree admits a small area drawing satisfying any given aspect ratio in the orthogonal straight-line drawing type. Our results are briefly summarized as follows. Let T be a bounded-degree tree with n vertices. Firstly, we show that T admits an upward straight-line drawing with area O (n loglog n) . If T is binary, we can obtain an O (n loglog n) -area upward orthogonal drawing in which each edge is drawn as a chain of at most two orthogonal segments and which has O (n/ log n) bends in total. Secondly, we present O (n loglog n) -area (respectively, -volume) orthogonal straight-line drawing algorithms for binary trees with arbitrary aspect ratios in 2-dimension (respectively, 3-dimension). Finally, we present some experimental results which shows the area requirements, in practice, for (order-preserving) upward drawing are much smaller than theoretical bounds obtained through analysis.

Whether CD8 T cell memory exists outside secondary lymphoid organs is unclear. Using an adoptive transfer system that enables tracking of OVA-specific CD8 T cells, we explored the antigenic requirements for inducing CD8 T cell memory and identified intestinal mucosa memory cells. Although systemic immunization with soluble OVA induced clonal expansion, memory CD8 cells were not produced. In contrast, infection with virus-encoding OVA induced memory CD8 cells in the periphery and the lamina propria and intraepithelial compartments of the intestinal mucosa. Mucosal memory cells expressed a distinct array of adhesion molecules as compared with secondary lymphoid memory cells, suggesting that there may be separate mucosal and systemic memory pools. Mucosal CD8 memory cells rapidly produced IFN-γ after Ag stimulation. Reactivation of memory cells by Ag feeding resulted in increased cell size and up-regulation of CD28 and CD11c. CD8 mucosal memory cells exhibited ex vivo lytic activity that was up-regulated dramatically following Ag reencounter in vivo. Interestingly, reactivation of memory cells did not require CD28-mediated costimulation. The ability of the intestinal mucosa to maintain CD8 memory cells provides a potential mechanism for effective mucosal vaccination.

We present efficient solutions on an RMESH for the following two problems: (i) The range minima problem: Given an array of real numbers, A =( a 1 ,…, a n ), preprocess A so that, after preprocessing, for any two query indices 1≤ i ≤ j ≤ n , min { a i ,…, a j } can be found efficiently. (ii) The range co-minima problem: Given an array of positive integers, B =( b 1 ,…, b n ) with b i ≤ n for all i , preprocess B so that, after preprocessing, for any two query indices 1≤ i ≤ j ≤ n , the minimum positive integer not in { b i ,…, b j } can be found efficiently. In other words, min {{1,2,…, n +1}−{ b i ,…, b j }} is to be found. Our preprocessing algorithms for both problems take constant time on an n × n RMESH, and a query can be answered in constant time using a single processor.

Primary cutaneous aggressive epidermotropic CD8(+) cytotoxic T-cell lymphoma is characterized by a proliferation of epidermotropic CD8(+) cytotoxic T cells and an aggressive clinical behavior. Patients present with localized or disseminated eruptive papules, nodules and tumors. We report a case of primary cutaneous aggressive epidermotropic CD8(+) cytotoxic T-cell lymphoma with unusual clinical manifestation. The lesion occurred as multiple brownish macules and flat-topped papules on the hands, feet and face in a 25-year-old woman.

In NC, one can decompose an n-vertex rectilinear polygon into O(n) rectangles, allowing Steiner points, so that any horizontal or vertical segment inside the polygon intersects O(logn) rectangles.

This paper presents a new method for selecting the force-reflection gain in a position-force type bilateral teleoperation system. The force-reflection gain greatly affects the task performance of a teleoperation system; too small gain results in poor task performance while too large gain results in system instability. The maximum boundary of the gain guaranteeing the stability greatly depends upon characteristics of the elements in the system such as: a master arm which is combined with the human operator's hand and the environments with which the slave arm contacts. In normal practice, it is, therefore, very difficult to determine such maximum boundary of the gain. To overcome this difficulty, this paper proposes a force-reflection gain selecting algorithm based on artificial neural network and fuzzy logic. The method estimates characteristics of the master arm and the environments by using neural networks and, then, determines the force-reflection gain from the estimated characteristics by using fuzzy logic. In order to show the effectiveness of the proposed algorithm, a series of experiments are conducted under various conditions of teleoperation using a laboratory-made telerobot system.

Dekel, Hu and Ouyang presented an O(N2) time algorithm for finding all compact sets of an edge-weighted graph G with M edges and N vertices. This is optimal provided G is represented by an adjacency matrix. Assuming G is represented by an adjacency list, we present an improved implementation of their algorithm which takes O(M + N log N) time to find and O(L) time to list all the compact sets, where L is the sum of the sizes of all compact sets of G.

Various techniques for personalized recommendation have been studied. One of the most promising such techniques is collaborative filtering (CF). However, CF is unable to produce high quality recommendations when user rating data is lacking or insufficient. To address this “sparsity” problem of CF systems, this paper proposes a hybrid recommendation system. The proposed system improves recommendation quality by exploiting trust scores between users in a social network. The proposed system overcomes the weakness of CF for sparse user ratings databases and yields better performance than the conventional CF method.