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Green mandarins are widely consumed unripe as mandarin oranges (Citrus unshiu Marcov.), which exhibit anti-inflammatory and anti-wrinkle effects by inhibiting the production of inflammatory cytokines and matrix metalloproteinase. A randomized, double-blind, placebo-controlled clinical study was performed to verify the skin improvement efficacy and safety of green mandarin extract (PTE). For the standardization of PTE, narirutin was set as a marker compound, and PTE with a constant narirutin content was prepared for the study. After randomizing subjects with periorbital wrinkles, they were orally administered PTE (300 mg/day) or a placebo for 12 weeks. Periorbital wrinkles were measured using PRIMOSCR SF. Skin elasticity, moisture content, transepidermal water loss, and gloss were also measured. In the study results, the depth, volume, and skin roughness of the periorbital wrinkles were significantly improved compared to the control group (p = 0.011, 0.009, and 0.004, respectively). The survey confirmed that the skin condition improved after PTE consumption for 12 weeks. No adverse reactions associated with PTE were observed during the study period. Thus, the results demonstrate that PTE effectively improves UV-induced skin wrinkles. Therefore, it is considered that PTE has sufficient value as a functional food ingredient that can prevent skin aging.

Magnolia flower buds are a source of herbal medicines with various active compounds. In this study, differences in the distribution and abundance of major essential oils, phenolic acids, and primary metabolites between white flower buds of Magnolia heptapeta and violet flower buds of Magnolia denudata var. purpurascens were characterised. A multivariate analysis revealed clear separation between the white and violet flower buds with respect to primary and secondary metabolites closely related to metabolic systems. White flower buds contained large amounts of monoterpene hydrocarbons (MH), phenolic acids, aromatic amino acids, and monosaccharides, related to the production of isoprenes, as MH precursors, and the activity of MH synthase. However, concentrations of β-myrcene, a major MH compound, were higher in violet flower buds than in white flower buds, possibly due to higher threonine levels and low acidic conditions induced by comparatively low levels of some organic acids. Moreover, levels of stress-related metabolites, such as oxygenated monoterpenes, proline, and glutamic acid, were higher in violet flower buds than in white flower buds. Our results support the feasibility of metabolic profiling for the identification of phytochemical differences and improve our understanding of the correlated biological pathways for primary and secondary metabolites.

Magnolia flower buds are a source of herbal medicines with various active compounds. In this study, differences in the distribution and abundance of major essential oils, phenolic acids, and primary metabolites between white flower buds of Magnolia heptapeta and violet flower buds of Magnolia denudata var. purpurascens were characterised. A multivariate analysis revealed clear separation between the white and violet flower buds with respect to primary and secondary metabolites closely related to metabolic systems. White flower buds contained large amounts of monoterpene hydrocarbons (MH), phenolic acids, aromatic amino acids, and monosaccharides, related to the production of isoprenes, as MH precursors, and the activity of MH synthase. However, concentrations of β-myrcene, a major MH compound, were higher in violet flower buds than in white flower buds, possibly due to higher threonine levels and low acidic conditions induced by comparatively low levels of some organic acids. Moreover, levels of stress-related metabolites, such as oxygenated monoterpenes, proline, and glutamic acid, were higher in violet flower buds than in white flower buds. Our results support the feasibility of metabolic profiling for the identification of phytochemical differences and improve our understanding of the correlated biological pathways for primary and secondary metabolites.

// Jung Wook Huh 1 , Sung Chun Kim 2 , Insuk Sohn 3 , Sin-Ho Jung 3, 4 , Hee Cheol Kim 1 1 Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea 2 Biois Corp, Seoul, Korea 3 Biostatistics and Clinical Epidemiology Center, Samsung Medical Center, Seoul, Korea 4 Department of Biostatistics and Bioinformatics, Duke University, Durham, NC, USA Correspondence to: Hee Cheol Kim, e-mail: hckim@skku.edu Keywords: aptamer, colon cancer, prognosis Received: November 02, 2015 Accepted: February 11, 2016 Published: February 19, 2016 ABSTRACT Background: In this study, we established and validated a model for predicting prognosis of stage IIA colon cancer patients based on expression profiles of aptamers in serum. Methods: Bloods samples were collected from 227 consecutive patients with pathologic T3N0M0 (stage IIA) colon cancer. We incubated 1,149 serum molecule-binding aptamer pools of clinical significance with serum from patients to obtain aptamers bound to serum molecules, which were then amplified and marked. Oligonucleotide arrays were constructed with the base sequences of the 1,149 aptamers, and the marked products identified above were reacted with one another to produce profiles of the aptamers bound to serum molecules. These profiles were organized into low- and high-risk groups of colon cancer patients based on clinical information for the serum samples. Cox proportional hazards model and leave-one-out cross-validation (LOOCV) were used to evaluate predictive performance. Results: During a median follow-up period of 5 years, 29 of the 227 patients (11.9%) experienced recurrence. There were 212 patients (93.4%) in the low-risk group and 15 patients (6.6%) in the high-risk group in our aptamer prognosis model. Postoperative recurrence significantly correlated with age and aptamer risk stratification (p = 0.046 and p = 0.001, respectively). In multivariate analysis, aptamer risk stratification (p < 0.001) was an independent predictor of recurrence. Disease-free survival curves calculated according to aptamer risk level predicted through a LOOCV procedure and age showed significant differences (p < 0.001 from permutations). Conclusion: Aptamer risk stratification can be a valuable prognostic factor in stage II colon cancer patients.

Article history: Received on: 02/02/2015 Revised on: 12/02/2015 Accepted on: 21/03/2015 Available online: 27/04/2015 For the purpose of developing anti-wrinkle cosmetic ingredients, the extracts from branches of a woody plant Sambucus sieboldiana var. pendula were examined on collagen synthesis activities using fibroblast HDFn cells. As a result, the S. sieboldiana ethanol extract (SSE) proved to activate the production of type I procollagen in a dose-dependent manner without showing cell toxicity. Phytochemical study was conducted to isolate the active constituents in the extracts by solvent fractionation followed by chromatographic purifications. From this procedure, two known compounds, kaempferol 3-O-sophoroside (1) and daucosterol (2), were identified by spectroscopic studies. From the isolates, the flavonoid glycoside 1 was verified to induce the synthesis of the type I procollagen dose-dependently. These results suggested that S. sieboldiana extract containing the flavonoid 1 could be useful as an active ingredient in wrinkle-care cosmetics.

Development of bioactive ingredients from natural sources has long been the research project of our laboratory. In this study, the extract from Corylus hallaisanensis Nakai branches was investigated and their anti-inflammatory constituents were identified. The prepared ethanol extract was successively partitioned into n-hexane, ethyl acetate, n-butanol and aqueous layers. Upon anti-inflammatory screenings, ethyl acetate fraction exhibited good nitric oxide production inhibitory activity in lipopolysaccharide-induced RAW 264.7 cells. Further phytochemical studies for the ethyl acetate fractions led to isolation of four constituents such as β-sitosterol (1), 3,3’,4’-tri-O-methylellagic acid (2), carpinontriol A (3) and carpinontriol B (4). All of the compounds were isolated for the first time from this plant. The isolates 2, 3 and 4 showed considerable inhibition on the production of nitric oxide in the RAW 264.7 cell without causing cell toxicities. And compounds 3 and 4 reduced the production of interleukin-6, an inflammatory cytokine, in dose-dependent manner in RAW 264.7 cells. Based on these results, C. hallaisanensis extracts could be potentially applicable as anti-inflammatory agents in pharmaceutical or cosmetic industries.

We proposed a 2 level tree based cluster based routing protocol for mobile ad hoc networks. it is our crucial goal to establish improved clustering’s structure in order to extend average node life-time and elevate the average packet delivery ratio. Because of insufficient wireless resources and energy, the method to form and manage clusters is useful for increasing network stability. but cluster-head fulfills roles as a host and a router in clustering protocol of Ad hoc networks environment. Therefore energy exhaustion of cluster-head causes communication interruption phenomenon. Effective management of cluster-head is key-point which determines the entire network performance. The scheme focuses on improving the performance the life time of the network and throughput through the management of cluster-heads and its neighbor nodes. In simulation, we demonstrated that it would obtain averagely better 17% performance than LS2RP.Keywords:Ad Hoc Networks, Routing Protocol, 2-Level Tree

클라이언트와 사회복지사의 관계는 사회복지실천의 중심으로 간주되어 왔지만 사회복지실천관계에 대한 현행 담론은 이론적 정향과 실천적 유용성 면에서 한계를 보이고 있다. 이런 상황에서 최근 사회 과학에서도 주목을 받고 있는 노자 도덕경은 유력한 대안 담론으로 검토될 만하다. 크게 본체론, 개체 론, 수양론을 아우르고 있는 도덕경은 원인론, 인과론, 개체주의로 상징되는 서양철학의 전통과 달리 객관주의, 긍정적 비판주의, 인본주의, 평등주의, 상호성과 관계성을 지향하는 유기적 세계관을 지향한 다. 본 연구에서는 이와 같은 노자 철학을 통해 사회복지실천관계론을 모색함으로써 다음과 같은 새로 운 가능성을 도출해 보았다. 첫째, 사회복지실천의 지향점을 ‘자연적 인본주의’로 설정함으로써 실천관 계를 인간본성에 근거한 상보적 존재로 규정한다. 둘째, 스스로 그러하다는 의미에서 자연스러운 존재 로서 인간본성을 규정함으로써 클라이언트의 잠재적 가능성과 이를 저해하는 인위적 억압을 인식한다. 셋째, 노자적 관점을 취하는 사회복지사는 폐쇄적 전문주의를 넘어 성찰과 무위(無爲)의 실천 주체로 설정된다. 이와 같이 노자 도덕경은 서구중심의 관계론이 가진 모더니즘과 포스트모더니즘의 이항 대립적 한계를 넘어 한국적 사회복지실천 관계를 모색하는 과정에서 중요한 이론적, 실천적 자원으로 활 용될 수 있을 것으로 보인다.

Ultrasonic shears is currently in wide use as an energy device for minimal invasive surgery. There is an advantage of minimizing the carbonization behavior of the tissue due to the vibrational energy transfer system of the transducer by applying a piezoelectric ceramic. However, the vibrational energy transfer system has a pitfall in energy consumption. When the movement of the forceps is interrupted by the tissue, the horn which transfers the vibrational energy of the transducer will be affected. A study was performed to recognize different tissues by measuring the impedance of the transducer of the ultrasonic shears in order to find the factor of energy consumption according to the tissue. In the first stage of the study, the voltage and current of the transducer connecting portion were measured, along with the phase changes. Subsequently, in the second stage, the impedance of the transducer was directly measured. In the final stage, using the handpiece, we grasped the tissue and observed the impedance differences appeared in the transducer To verify the proposed tissue distinguishing method, we used the handpiece to apply a force between 5N and 10N to pork while increasing the value of the impedance of the transducer from 400 .. It was found that fat and skin tissue, tendon, liver and protein all have different impedance values of 420 , 490 , 530 , and 580 , respectively. Thus, the impedance value can be used to distinguish the type of tissues grasped by the forceps. In the future study, this relationship will be used to improve the energy efficiency of ultrasonic shears.

Routing protocol in ad hoc mobile networking has been an active research area in recent years. However, the environments of ad hoc network tend to have vulnerable points from attacks, because ad hoc mobile network is a kind of wireless network without centralized authentication or fixed network infrastructure such as base stations. Also, existing routing protocols that are effective in a wired network become inapplicable in ad hoc mobile networks. To address these issues, several secure routing protocols have been proposed: SAODV and SRPTES. Even though our protocols are intensified security of networks than existing protocols, they can not deal fluidly with frequent changing of wireless environment. Moreover, demerits in energy efficiency are detected because they concentrated only safety routing. In this paper, we propose an energy efficient secure routing protocol for various ad hoc mobile environment. First of all, we provide that the nodes distribute security information to reliable nodes for secure routing. The nodes constitute tree-structured with around nodes for token escrow, this action will protect invasion of malicious node through hiding security information. Next, we propose multi-path routing based security level for protection from dropping attack of malicious node, then networks will prevent data from unexpected packet loss. As a result, this algorithm enhances packet delivery ratio in network environment which has some malicious nodes, and a life time of entire network is extended through consuming energy evenly.

The necessity of wireless sensor networks is increasing in the recent years. So many researches are studied in wireless sensor networks. The clustering algorithm provides an effective way to prolong the lifetime of the wireless sensor networks. The one-hop routing of LEACH algorithm is an inefficient way in the energy consumption of cluster-head, because it transmits a data to the BS(Base Station) with one-hop. On the other hand, other clustering algorithms transmit data to the BS with multi-hop, because the multi-hop transmission is an effective way. But the multi-hop routing of other clustering algorithms which transmits data to BS with multi-hop have a data bottleneck state problem. The unequal clustering algorithm solved a data bottleneck state problem by increasing the routing path. Most of the unequal clustering algorithms partition the nodes into clusters of unequal size, and clusters closer to the BS have small-size the those farther away from the BS. However, the energy consumption of cluster-head in unequal clustering algorithm is more increased than other clustering algorithms. In the thesis, I propose an energy efficient unequal clustering algorithm which decreases the energy consumption of cluster-head and solves the data bottleneck state problem. The basic idea is divided a three part. First of all I provide that the election of appropriate cluster-head. Next, I offer that the decision of cluster-size which consider the distance from the BS, the energy state of node and the number of neighborhood node. Finally, I provide that the election of assistant node which the transmit function substituted for cluster-head. As a result, the energy consumption of cluster-head is minimized, and the energy consumption of total network is minimized.

Wireless Sensor Networks are consisted of sensor nodes that communicated with each other to transmit information. Because sensor nodes have physically many limits, wireless sensor networks are hard to adopt for traditional networks. Transmissions are consumed most energy of sensor nodes. That's why energy-efficient transmission techniques and QoS support techniques for different kind of data are most important in wireless sensor networks. The thesis proposes the agent based framework for energy distribution and QoS in wireless sensor networks. Agents have its own behavior policy by means of a gene, which is optimized by genetic operations. Agents behavior to distribute energy consumption over sensor nodes. Simulation results show that the enhanced framework extends the lifetime of sensor nodes. Successful transmission ratios of emergency data and non emergency data are increased by 27% and 14%, respectively. Also, the results demonstrate that Qos of networks are improved.Keywords:Sensor Network, MONSOON, QoS

Conventional clinical decision support systems are generally based on a single classifier or a simple combination of these models, showing moderate performance. In this paper, we propose a classifier ensemble-based method for supporting the diagnosis of cardiovascular disease (CVD) based on aptamer chips. This AptaCDSS-E system overcomes conventional performance limitations by utilizing ensembles of different classifiers. Recent surveys show that CVD is one of the leading causes of death and that significant life savings can be achieved if precise diagnosis can be made. For CVD diagnosis, our system combines a set of four different classifiers with ensembles. Support vector machines and neural networks are adopted as base classifiers. Decision trees and Bayesian networks are also adopted to augment the system. Four aptamer-based biochip data sets including CVD data containing 66 samples were used to train and test the system. Three other supplementary data sets are used to alleviate data insufficiency. We investigated the effectiveness of the ensemble-based system with several different aggregation approaches by comparing the results with single classifier-based models. The prediction performance of the AptaCDSS-E system was assessed with a cross-validation test. The experimental results show that our system achieves high diagnosis accuracy (>94%) and comparably small prediction difference intervals (

Recently, wireless networking devices that depend on the limited Battery and power-saving of wireless hosts became important issue. Batteries can provide a finite amount of energy, therefore, to increase battery lifetime, it is important to design techniques to reduce energy consumption by wireless hosts. This paper improved power saying mechanism in Distributed Coordination Function(DCF) of IEEE 802.11. In the IEEE 802.11 power saving mechanism specified for DCF, time is divided into so-called beacon intervals. At the start of each beacon interval, each node in the power saving mode periodically wakes up during duration called the ATIM Window. The nodes are required to be synchronized to ensure that all nodes wake up at the same time. During the ATIM window, the nodes exchange control packets to determine whether they need to stay awake for the rest of the beacon interval. The size of the ATIM window has considerably affected power-saving. This paper can provide more power-saving than IEEE 802.11 power saving mode because ATIM window size is efficiently increased or decreased.

New multimedia services over the cellular/WLAN overlay networks require different Quality of Service (QoS). Therefore, efficient network management system is necessary in order to provide QoS sensitive multimedia services while enhancing network performance. In this paper, we propose a new online network management scheme that implements bandwidth reservation, congestion and transmission control strategies. Our online approach to network management exhibits dynamic adaptability, flexibility, and responsiveness to the current traffic conditions in multimedia overlay networks. Simulation results indicate the superior performance of our proposed scheme to strike the appropriate performance balance between contradictory QoS requirements under widely varying diverse traffic loads.

Accurate tumor localization is essential for minimally invasive surgery. This study describes the development of a novel endoscopic fluorescent band ligation method for the rapid and accurate identification of tumor sites during surgery. The method utilized a fluorescent rubber band, made of indocyanine green (ICG) and a liquid rubber solution mixture, as well as a near-infrared fluorescence laparoscopic system with a dual light source using a high-powered light-emitting diode (LED) and a 785-nm laser diode. The fluorescent rubber bands were endoscopically placed on the mucosae of porcine stomachs and colons. During subsequent conventional laparoscopic stomach and colon surgery, the fluorescent bands were assayed using the near-infrared fluorescence laparoscopy system. The locations of the fluorescent clips were clearly identified on the fluorescence images in real time. The system was able to distinguish the two or three bands marked on the mucosal surfaces of the stomach and colon. Resection margins around the fluorescent bands were sufficient in the resected specimens obtained during stomach and colon surgery. These novel endoscopic fluorescent bands could be rapidly and accurately localized during stomach and colon surgery. Use of these bands may make possible the excision of exact target sites during minimally invasive gastrointestinal surgery.

Most wavelength assignment algorithms assume that every node has infinite ADMs and I/O blocking is excluded. Furthermore wavelengths continue to occur intermittently in the network using existing algorithms. This can result in increased link blocking under dynamic traffic circumstances. In audition, it can create time-complexity problems such as O(W ) in the worst case scenario. In this paper, we propose a new wavelength assignment algorithm which has time-complexity of O(W ) and considers both I/O and link blocking. The basic idea is to maximize the number of links where wavelengths will be assigned continuously after present assignment. As a result, the number of intermittent wavelengths is minimized, and blocking probabilities are decreased.

In this study, we describe a novel approach to human cancer therapy that is based upon trans-splicing ribozyme-mediated replacement of cancer-specific RNAs with new transcripts that exert therapeutic activities. We have developed a specific ribozyme that can reprogram human telomerase reverse transcriptase (hTERT) RNA to induce transgene activity selectively in cancer cells that express the RNA. The ribozyme-mediated triggering of the transgene expression was accomplished via a high-fidelity trans-splicing reaction with the targeted residue in the hTERT-expressing cells. The ribozyme also induced cytotoxic activity in various hTERT-expressing cancer cells, hence selectively retarding the growth of those cells. Efficient and specific cell regression was also detected with ganciclovir (GCV) treatment only in hTERT-positive cancer cells, which were established to express stably the specific ribozyme that contains the herpes simplex virus thymidine kinase (HSV-tk) gene. Tissue-specific expression of the ribozyme could further augment the target specificity of the ribozyme. Importantly, we observed efficient regression of tumors with GCV treatment in mice that had been inoculated subcutaneously with hTERT-positive cancer cells that stably expressed the specific ribozyme that contains HSV-tk. These results suggest that the hTERT RNA-targeting trans-splicing ribozyme could be a powerful agent for tumor-targeted specific gene therapy.

We fabricated a tunable fiber ring laser consisting of a novel strain device and fiber Bragg gratings. The lasing power and FWHM bandwidth of the optical fiber ring laser was -12dBm and 0.05nm respectively. The fiber ring laser was tuned as much as 10nm at a 8000.

Server clusters for Internet services can yield both high performance and cost effectiveness. Contemporary approaches to cluster design must confront the tradeoff between dynamic load-balancing and efficiency when dispatching client requests to servers in the cluster. In this paper we describe a packet filtering-based RR scheduling scheme, intended to be an easily implemented scheme for hosting Internet services on a server cluster in a way transparent to clients. We take a non-centralized approach, in which client packets sent to the cluster's single IP address are broadcast to all of its servers. Packets requesting that a new TCP session be set up cause counters in each server to be incremented; if a server's counter matches its fixed unique ID, it takes charge of the session, else it ignores the packet. This yields a round-robin type algorithm. We describe this approach in detail, and present results of simulations that show it achieves higher performance (in terms of throughput and reliability) than similar approaches based on client-IP hashing and dispatcher-based RR.

Natural orifice transluminal endoscopic surgery (NOTES) is an emerging surgical technique. We aimed to design, create, and evaluate a new semi-automatic snake robot for NOTES. The snake robot employs the characteristics of both a manual endoscope and a multi-segment snake robot. This robot is inserted and retracted manually, like a classical endoscope, while its shape is controlled using embedded robot technology. The feasibility of a prototype robot for NOTES was evaluated in animals and human cadavers. The transverse stiffness and maneuverability of the snake robot appeared satisfactory. It could be advanced through the anus as far as the peritoneal cavity without any injury to adjacent organs. Preclinical tests showed that the device could navigate the peritoneal cavity. The snake robot has advantages of high transverse force and intuitive control. This new robot may be clinically superior to conventional tools for transanal NOTES.

We introduce new techniques for hiding communication overheads involved in dynamic load balancing for hypercubes, meshes and trees. The basic idea is either coalescing some phases of balancing to overlap the transfer of load units on different links or dividing each phase into steps to pipeline the transfer of load unit by unit for maximum utilization of links. Previous schemes perform transfer in a sequential way, leaving many links idle in some phases. The first technique (method1 technique in the paper) collects information about transfers on all the links in all phases and determines which can be overlapped with which. We construct new phases such that all the transfer actions that can be overlapped are combined into a phase. In some cases (especially severely uneven load distribution) the method1 is not so effective since processors should wait for incoming units before sending out. To remedy this, we introduce a new technique (method2 technique in the paper) in which each phase is split into steps and one unit is transferred in a step. Since each processor does not have to wait for all of the units to be sent to its neighbor before sending out, the method1 technique enhances the utilization of links. Our techniques are shown via simulation to result in 15–65% reduction (hiding) to known techniques, depending on the initial load distribution.

Endothelial progenitor cells (EPCs) were recently demonstrated to exist in human cord blood. Phytohaemagglutinin (PHA), a potent mitogen for mononuclear cells was used to induce EPCs from unsorted cord blood mononuclear cells (CBMCs). Adherent cells in clusters appeared approximately 24 h after CBMCs were cultured in plain Roswell Park Memorial Institute media containing 10% fetal bovine serum (culture media) and PHA. Adherent cells were further propagated for 1 week in plain culture media. Flow cytometry and Di-I staining analyses showed that CD45-, CD34+, Flk-1+, CD31+ or VE-cadherin+ EPCs were induced and that they were mainly from the CD34+ cell compartment. When enriched CD34+ cells alone were stimulated with culture supernatant of the PHA-activated CBMCs, they neither proliferated readily nor induced EPCs. Because EPCs first appeared within the clustering cells that expressed high levels of fibronectin and vascular endothelial growth factor (VEGF), our data suggest that both cell-cell/cell-matrix interaction and the local VEGF action are important in the induction of EPCs. Thus, we demonstrate for the first time that EPCs are induced from human cord blood stem cell populations that interact with neighbouring PHA-activated CBMCs. This finding may have a significant implication in inflammatory cell-mediated vasculogenesis and angiogenesis in vivo.

The search for differentially expressed genes in gastric cancer may help define molecular alterations and molecular diagnosis of gastric cancer. Using the differential display PCR technique, we identified 18 genes that are differentially expressed between normal and tumor human gastric tissues. Their expressions were verified with reverse Northern blot analysis and Northern blot analysis. Oxidative phosphorylation-related genes, antizyme inhibitor of ornithine decarboxylase, protein phosphatase-1beta, 35-kDa peroxisomal membrane protein, and cystic fibrosis transmembrane conductance receptor were highly expressed in tumor tissue, whereas pepsinogen A, Na-K ATPase alpha subunit, nerve growth factor receptor, and alpha-tropomyosin were highly expressed in normal tissue. In addition, 3 unknown genes were found to be differentially expressed in paired gastric tissues. These differentially expressed genes may provide significant opportunities for further understanding of gastric carcinogenesis and the molecular diagnosis of gastric cancer.

NMR and topochemical studies of irreversible HIV-1 protease inhibitors containing a cis-epoxide as amide isostere have been carried out to identify conformational preference of the inhibitors in solution. The inhibitors prefer to adopt extended conformations similar to the beta-strand in solution.

Novel irreversible HIV-1 protease inhibitors containing sulfonamide and sulfone as amide bond isosteres were designed, synthesized, and kinetically characterized. A representative compound 2 displayed rapid, time-dependent inactivation of HIV-1 protease and high potency in cell culture with IC50 of 6.6 nM.

A novel isostere was designed for the inactivation of HIV protease on the basis of mechanistic and structural information. Key factors of the inactivator are the cis-epoxide for the nucleophilic addition of the active site aspartic residue and two amide carbonyls at P2 and P1' for the formation of the hydrogen-bondings with an essential structural water molecule. Novel isostere was designed for the inactivation of HIV protease on the basis of mechanistic and structural information. The key factors of the inactivators are the cis-epoxide for the nucleophilic addition of the aspartic residue at the active site and two amide carbonyls at P2 and P1′ for the formation of the hydrogen-bondings with an essential structural water molecule.

β-Methanesulfonyl-L-valine as a surrogate for asparagine and valine was designed, synthesized, and characterized. A representative compound 1 showed IC 50 of 4.9 nM.

Pseudo -C 2 -symmetric irreversible inhibitors of HIV-1 protease containing cis -epoxide were designed, synthesized, and kinetically characterized. Introduction of a Gly residue into P 1 ' of the inactivators yielded strong time-dependent irreversible ones with k ina /K i ranging from 1.5×10 8 to 3.4×10 5 M −1 min −1 .

β-Methanesulfonyl-L-valine as a surrogate for asparagine and valine was designed, synthesized, and characterized. A representative compound 1 showed IC 50 of 4.9 nM.

Novel irreversible HIV-1 protease inhibitors containing sulfonamide and sulfone as amide bond isosteres were designed, synthesized, and kinetically characterized. A representative compound 2 displayed rapid, time-dependent inactivation of HIV-1 protease and high potency in cell culture with IC50 of 6.6 nM.

It is our interest to design and develop a high power pulser system employing microplasma discharge in a spark gap system. The type of discharge generates short electric pulses capable of both the characteristics of high repetition rate and fast rise time. Such a switch pulser has wide applications in the industry. An efficient electrical discharge in the spark gap is very important for the switching operation. The regime of operation utilizes the residual plasma in the inter pulse recovery of the spark gap to increase the repetition rate. Therefore, the mechanisms of the discharge in a controlled manner, such as the plasma discharge by the arc channel, the dielectric recovery process as well as residual plasma in the post arc period are of great importance to ensure the high repetition rate. The aforementioned mechanisms are established through optimization of the circuit element parameters such as the electrode geometry, the gap distance, the gas pressure, the gas type as well as the applied voltage and current ratings.

Over the past 15 years, South Korea has been actively pursuing a sustainable waste management strategy, which includes the thermal treatment of non-recyclable waste. Over 18,000 tons/day of waste are thermally treated in South Korea in over 40 plants. Since municipalities are not allowed to export waste outside of their respective jurisdictions, plants range in size from 25 ton/day to over 500 tons/day. There are currently 7 plants on 6 sites using gasification technology in South Korea, with the first plant in operation since 2001. The purpose of this paper is to describe how the downdraft gasification technology works, integration of the technology into a complete energy from waste facility, operating history, availability, emission levels and lessons learned. Synopsis of the technology: Curbside Municipal Solid Waste (MSW) is rough shredded and fed into the primary chamber through an air lock. The gasification occurs in the low temperature negative pressurized primary chamber where the MSW goes through drying, pyrolysis and gasification stages. The resulting syn-gas is filtered through the char bed into a secondary chamber where combustion takes place, producing a hot inert flue gas. A Heat Recovery Steam Generator (boiler) is used to recover the thermal energy from the flue gas. The char at the bottom of the primary chamber is oxidized, creating the heat for the gasification process. The air pollution control system is located after the Boiler and consists of carbon and lime injection followed by a bag filter. Operating history, availability and emission levels are presented.Copyright © 2009 by ASME

The mechanism of interaction of quinols and phenols with dopamine beta-monooxygenase (D beta M) has been investigated. The ratio of quinone formation (from catechol) to oxygen consumption rises from a value of 1 in the presence of phenethylamine substrate to 2 in the absence of substrate. These results implicate quinol oxidation at both the reductant- and substrate-binding sites of D beta M. In the presence of saturating ascorbate, catechol and p-hydroquinol behave as mechanism-based inhibitors of D beta M, with partitioning ratios of turnover to inactivation of 21:1 and 41:1, respectively. Phenol is found to inactivate the enzyme in a manner similar to p-cresol, suggesting that the methyl group of p-cresol is not an essential component of enzyme inhibition. Solvent isotope effects on inactivation and turnover have been measured for various inactivators. Although the majority of these inhibitors, including catechol, p-hydroquinol, aniline, phenethylenediamine, and benzylhydrazine, are characterized by relatively small solvent isotope effects (1.5-2.5) on the inactivation rate constant (ki), solvent isotope effects on ki for phenol and p-cresol are 5.7 and 7.4, respectively. By contrast, solvent isotope effects on the turnover of p-cresol are almost unity. Using p-cresol-d7 as substrate, we observe D(kcat) = 5.2 and D(kcat/Km) = 3.1, while isotope effects on inactivation are D(ki) = 0.95 and D(ki/Ki) = 0.59. These results lead us to propose that inhibitors fall into two mechanistic classes, involving either one-electron oxidation to form radical cation intermediates (quinols) or hydrogen atom abstraction (phenols).(ABSTRACT TRUNCATED AT 250 WORDS)

We present a biology-inspired probabilistic graphical model, called the hypernetwork model, and its application to medical diagnosis of disease. The hypernetwork models are a way of simulated DNA computing. They have a set of hyperedges representing a subset of features in the training data. These characteristics allow the hypernetwork models to work similarly to associative memories and make their learning results more understandable. This comprehensibility is one of main advantages of the models over other machine learning algorithms such as support vector machines and artificial neural networks which are used in a wide range of applications but are not easy to understand their learning results. Since medical applications require both competitive performance and understandability of results, the hypernetwork models are suitable for this kind of applications. However, ordinary hypernetwork models have limitations that hyperedges cannot be changed after they are sampled once. To improve this diversity problem, we adopted simple evolutionary computation method, the hyperedges replacement strategy as the method of keeping the diversity into conventional hypernetworks in addition to error correction for model learning. To show the improvement, we used aptamer-based cardiovascular disease data. Experiment results show that the hypernetworks can achieve fairly competitive performance and the results are also comprehensible.

Reconfiguration of WDM networks allows network operators to reconfigure the topologies in response to changing traffic demands to improve the QoS. To reconfigure the current virtual topology, the time to reconfigure is decided, and then a target topology is created. Next, real transition between topologies is occurred. We propose a VTR controller for WDM networks. First, our controller decides when current virtual topology is reconfigured. Some traffic may travel with single hop lightpaths and others may not. What the amount of traffic which is serviced through multi-hop increases shows that current virtual topology is not adequate for traffic demands. We use this information to reconfigure. And, the controller creates a target topology. As discontinuous wavelengths increases in networks, it can increase the difficulty of establishing single hop lightpaths for future traffic. Hence, the controller establishes the lightpaths which would remain discontinuous as few as possible after assigning.

Single-walled carbon nanotube biosensor was developed for the detection of Escherichia coli using aptamer-functionalized carbon nanotube field effect transistors. RNA-based E. coli aptamer was chosen by the SELEX process, and immobilized on sidewalls of carbon nanotubes by CDI-Tween 20 linking molecules. The electrical response of the carbon nanotube sensor before and after the binding of E. coli aptamer and E. coli were studied.

A reconfigurable mesh consists of a mesh-connected topology augmented by a dynamically reconfigurable bus system. Efficient utilization of processing resources in a large, multiuser parallel system depends on the reliable processor management scheme. We present a dynamic and reliable processor allocation strategy to increase the performance of mesh-connected parallel systems with faulty processors. The idea is to reconfigure a faulty mesh system into a maximum convex system using the fault-free boundary nodes to compensate for the nonboundary faulty nodes. To utilize the nonrectangular shaped system parts, our strategy tries to allocate L-shaped submeshes instead of signaling the allocation failure. Extensive simulations show that the strategy performs more efficiently than other strategies in terms of the completion time, the job response time and the system utilization.

Dynamic load balancing on hypercube multiprocessors is considered with emphasis on quantized loads. Quantized loads are divisible only in a fixed size. First, we show that a direct application of the well-known Dimension Exchange Method (DEM) to quantized loads may result in difference in assigned loads to processors as large as log N units after balancing for a hypercube of size N. Then we propose a new method which reduces the maximum difference by half to [1/2 log N]. The claim is proved both by analysis of possible cases incrementing the difference on each phase of balancing and by enumerating all possible combination of load for hypercubes of limited sizes using a computer. To estimate the accumulated effect of balancing instances under real-world parallel processing environment, a simulation for hypercube multiprocessors using SLAM II tool is performed. The result shows about 30% improvement in speedup which results from reduced processing time, which in turn results from reduced nonuniformity.

We propose a new ATM switch architecture with output queueing. The proposed switch, FBSF (FAB Banyan switching fabrics) can deliver up to 2r packets simultaneously destined for the same outlet in a single time slot. Unlike the existing switches with multiple outlets where r parallel N/spl times/N networks are used to deliver more than one packet to each output port, the proposed FBSF switch uses only two N/spl times/N FAB networks, resulting in a simpler hardware implementation. The switch fabric consists of Batcher sorter; a radix-r double shuffle network, r-packet distributors, two FAB networks, and output buffer modules. The proposed FBSF switch also supports multimedia traffic such as voice and compressed video data as well as text data. The performance of the switch fabric is evaluated by measures of throughput, packet delay, and packet loss probability. The numerical results show that nearly perfect throughput can be archived by the proposed switch in the case where r/spl ges/2.