bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of New Dietary Fiber from Japanese Apricot (Prunus mume Sieb. et Zucc.) on Gut Function and Intestinal Microflora in Adult Mice
Authors: Tamura Motoi , Ohnishi Yuriko , Kotani Tatsuya , Gato Nobuki
Published: March 2011

Much attention has been focused recently on functional foods. Ume, the Japanese name for the apricot of Prunus mume Sieb. et Zucc., is an example of a Japanese traditional functional food. There are, however, few reports on the effects of fiber from this fruit on bowel function. With this objective, we prepared ume fiber to test the hypothesis that it can change gut function and intestinal flora in mice. Mice were fed an ume fiber (UF) or cellulose (CF) diet (control) for 40 days. The fecal weight, fecal lipids, plasma lipids and cecal composition of the microflora were analyzed. The amount of feces was significantly greater in the UF group than in the CF group (p < 0.01). The fecal lipids content (% DW) of the feces sampled on the final days of the experiment were significantly greater in the UF group than in the CF group (p < 0.01). Plasma non-esterified fatty acids (NEFA) concentrations tended to be lower in the UF compared to the CF group (p = 0.058). Occupation ratios of Bacteroides and Clostridium cluster IV were significantly greater in the cecal flora of the UF group. Our results suggest that ume fiber possesses the fecal lipid excretion effects and feces bulking effects.
An Acetylenic Alkaloid from the Calcareous Sponge Leucetta sp.
Authors: Hermawan Idam , De Voogd Nicole J. , Tanaka Junichi
Published: March 2011

A new acetylenic alkaloid was isolated from the sponge Leucetta sp. The structure was established by analyzing spectroscopic data. The alkaloid showed cytotoxicity IC50 2.5 mg/mL against NBT-T2 cells.
Preparation of Calibration Standards of N1-H Paralytic Shellfish Toxin Analogues by Large-Scale Culture of Cyanobacterium Anabaena circinalis (TA04)
Authors: Watanabe Ryuichi , Suzuki Toshiyuki , Oshima Yasukatsu
Published: March 2011

Mouse bioassay is the official testing method to quantify paralytic shellfish toxins (PSTs) in bivalves. A number of alternative analytical methods have been reported. Some methods have been evaluated by a single laboratory validation. Among the different types of methods, chemical analyses are capable of identifying and quantifying the toxins, however a shortage of the necessary calibration standards hampers implementation of the chemical analyses in routine monitoring of PSTs in bivalves. In our present study, we studied preparation of major PST analogues as calibrants by large-scale cultivation of toxic freshwater cyanobacteria Anabaena circinalis TA04. The cells were steadily grown in 10 L bottle for 28 days. The primary N1-H toxins, C1/C2, were produced at a concentration of 1.3 ± 0.1 µmol/L. The intracellular and extracellular toxins occupied 80% and 20%, respectively. Over 220 µmol of the toxins was obtained from approximately 200 L of the culture over six months, demonstrating that it is sufficient to prepare saxitoxin analogues. The toxins were chemically converted to six N1-H analogues. Preparation of the analogues was carried out at relatively high yields (50–90%). The results indicate that our preparation method is useful to produce N1-H toxins. In our present study, detailed conditions for preparation of one of the rare N1-H analogues, gonyautoxin-5, were investigated.
Marine Biocatalysts: Enzymatic Features and Applications
Authors: Trincone Antonio
Published: March 2011

In several recent reports related to biocatalysis the enormous pool of biodiversity found in marine ecosystems is considered a profitable natural reservoir for acquiring an inventory of useful biocatalysts. These enzymes are characterized by well-known habitat-related features such as salt tolerance, hyperthermostability, barophilicity and cold adaptivity. In addition, their novel chemical and stereochemical characteristics increase the interest of biocatalysis practitioners both in academia and research industry. In this review, starting from the analysis of these featuring habitat-related properties, important examples of marine enzymes in biocatalysis will be reported. Completion of this report is devoted to the analysis of novel chemical and stereochemical biodiversity offered by marine biocatalysts with particular emphasis on current or potential applications of these enzymes in chemical and pharmaceutical fields. The analysis of literature cited here and the many published patent applications concerning the use of marine enzymes supports the view that these biocatalysts are just waiting to be discovered, reflecting the importance of the marine environment. The potential of this habitat should be thoroughly explored and possibly the way to access useful biocatalysts should avoid destructive large-scale collections of marine biomass for enzyme production. These two aspects are day by day increasing in interest and a future increase in the use of marine enzymes in biocatalysis should be expected.
Panduratin A Inhibits the Growth of A549 Cells through Induction of Apoptosis and Inhibition of NF-KappaB Translocation
Authors: Cheah Shiau-Chuen , Appleton David R. , Lee Sui-Ting , Lam May-Lynn , Hadi A. Hamid A. , Mustafa Mohd. Rais
Published: March 2011

In the present study we investigated the effects of panduratin A, isolated from Boesenbergia rotunda, on proliferation and apoptosis in A549 human non-small cell lung cancer cells. Cell proliferation and induction of apoptosis was determined by the real-time cellular analyzer (RTCA), MTT assay and High Content Screening (HCS). The RTCA assay indicated that panduratin A exhibited cytotoxicity, with an IC50 value of 4.4 µg/mL (10.8 µM). Panduratin A arrested cancer cells labeled with bromodeoxyuridine (BrdU) and phospho-Histone H3 in the mitotic phase. The cytotoxic effects of panduratin A were found to be accompanied by a dose-dependent induction of apoptosis, as assessed by DNA condensation, nuclear morphology and intensity, cell permeability, mitochondrial mass/ potential, F-actin and cytochrome c. In addition, treatment with an apoptosis-inducing concentration of panduratin A resulted in significant inhibition of Nuclear Factor-kappa Beta (NF-κB) translocation from cytoplasm to nuclei activated by tumor necrosis factor-alpha (TNF-α), as illustrated by the HCS assay. Our study provides evidence for cell growth inhibition and induction of apoptosis by panduratin A in the A549 cell line, suggesting its therapeutic potential as an NF-κB inhibitor.
Synthesis and In Vitro Antibacterial Activity of 7-(3-Amino-6,7-dihydro-2-methyl-2H-pyrazolo[4,3-c] Pyridin-5(4H)-yl)fluoroquinolone Derivatives
Authors: Guo Xin , Liu Ming Liang , Guo Hui Yuan , Wang Yu Cheng , Wang Ju Xian
Published: March 2011

A series of novel 7-(3-amino-6,7-dihydro-2-methyl-2H-pyrazolo[4,3-c]pyridin- 5(4H)-yl)fluoroquinolone derivatives were designed, synthesized and characterized by 1H-NMR, MS and HRMS. These fluoroquinolones were evaluated for their in vitro antibacterial activity against representative Gram-positive and Gram-negative strains. Results reveal that most of the target compounds exhibit good growth inhibitory potency against methicillin-resistant Staphylococcus epidermidis (MRSE) (MIC: 0.25–4 μg/mL) and Streptococcus pneumoniae (MIC: 0.25–1 μg/mL). In addition, compound 8f is 8–128 fold more potent than the reference drugs gemifloxacin (GM), moxifloxacin (MX), ciprofloxacin (CP) and levofloxacin (LV) against methicillin-resistant Staphylococcus aureus 10-05 and Streptococcus hemolyticus 1002 and 2–64 fold more active against methicillin-sensitive Staphylococcus aureus 10-03 and 10-04.
Immunosuppressive Activity of 8-Gingerol on Immune Responses in Mice
Authors: Lu Jing , Guan Shuang , Shen Xue , Qian Wenhui , Huang Guoren , Deng Xuming , Xie Guanghong
Published: March 2011

8-Gingerol is one of the principal components of ginger, which is widely used in China and elsewhere as a food, spice and herb. It shows immunosuppressive activity on the immune responses to ovalbumin (OVA) in mice. In the present study, we found that 8-gingerol suppressed lipopolysaccharide (LPS) and concanavalin A (ConA)-stimulated splenocyte proliferation in vitro. In vivo, 8-gingerol not only signiﬁcantly suppressed Con A-, LPS- and OVA-induced splenocyte proliferation (P < 0.05) but also decreased the percentage of CD19+ B cells and CD3+ T cell (P < 0.05) at high doses (50, 100 mg/kg). Moreover, OVA-speciﬁc IgG, IgG1 and IgG2b levels in OVA-immunized mice were reduced by 8-gingerol at doses of 50, 100 mg/kg. These results suggest that 8-gingerol could suppress humoral and cellular immune responses in mice. The mechanism might be related to direct inhibition of sensitized T and B lymphocytes.
In-Vitro Antagonistic Characteristics of Crude Aqueous and Methanolic Extracts of Garcinia kola (Heckel) Seeds against Some Vibrio Bacteria
Authors: Penduka Dambudzo , Okoh Omobola O. , Okoh Anthony I.
Published: March 2011

The methanolic and aqueous extracts of Garcinia kola seeds were screened for their anti-Vibrio activities against 50 Vibrio isolates obtained from wastewater final effluents in the Eastern Cape Province, South Africa. The crude extracts at 10 mg/mL exhibited appreciable inhibitory activities against most of the test Vibrio isolates, with zones of inhibition ranging from 10–19 mm for methanol extract and 8–15 mm for the aqueous extracts. The minimum inhibitory concentrations (MIC) of the methanol extract varied from 0.313 to 2.5 mg/mL while that for the aqueous extract was 10 mg/mL for all the susceptible Vibrio isolates. Rate of kill assay of the methanolic extracts against three selected Vibrio species showed bacteriostatic activities against all of them achieving 58% and 60% (Vibrio vulnificus AL042); 68% and 69% (Vibrio parahaemolyticus AL049); and 70% and 78% (Vibrio fluvialis AL040) killing of the test bacteria at 3× and 4 ×MIC values, respectively, after 2 h exposure time. We conclude that Garcinia kola seeds hold promise as a potential source of therapeutic compounds of relevance in Vibrio infections management.
Routes to Nanoparticle-Polymer Superlattices
Authors: Mehdizadeh Taheri Sara , Fischer Steffen , Förster Stephan
Published: March 2011

Nanoparticles can self-assemble into highly ordered two- and three-dimensional superlattices. For many practical applications these assemblies need to be integrated into polymeric matrices to provide stability and function. By appropriate co-assembly of nanoparticles and polymers it has become possible to tailor the nanoparticle superlattice structure via the length and stiffness of the polymer chains. The present article outlines and discusses established routes to nanoparticle-polymer superlattices. Recent progress has been remarkable so that the integration into functional devices has become the next challenge.
Airborne Remote Sensing of a Biological Hot Spot in the Southeastern Bering Sea
Authors: Churnside James H. , Brown Evelyn D. , Parker-Stetter Sandra , Horne John K. , Hunt George L. , Hillgruber Nicola , Sigler Michael F. , Vollenweider Johanna J.
Published: March 2011

Intense, ephemeral foraging events within localized hot spots represent important trophic transfers to top predators in marine ecosystems, though the spatial extent and temporal overlap of predators and prey are difficult to observe using traditional methods. The southeastern Bering Sea has high marine productivity along the shelf break, especially near marine canyons. At a hot spot located near Bering Canyon, we observed three foraging events over a 12 day period in June 2005. These were located by aerial surveys, quantified by airborne lidar and visual counts, and characterized by ship-based acoustics and net catches. Because of the high density of seabirds, the events could be seen in images from space-based synthetic aperture radar. The events developed at the shelf slope, adjacent to passes between the Aleutian Islands, persisted for 1 to 8 days, then abruptly disappeared. Build-up and break down of the events occurred on 24 hr time scales, and diameters ranged from 10 to 20 km. These events comprised large concentrations of euphausiids, copepods, herring, other small pelagic fishes, humpback whales, Dall’s porpoise, short-tailed shearwaters, northern fulmars, and other pelagic seabirds. The lidar and acoustic remote sensing data demonstrated that prey densities inside the events were several times higher than those outside, indicating the importance of including events in forage fish surveys. This implies a need for either very intensive traditional surveys covering large expanses or for adaptive surveys guided by remote sensing. To our knowledge, this is the first time that an Alaskan hot spot was monitored with the combination of airborne and satellite remote sensing.
A Comparison of Two Open Source LiDAR Surface Classification Algorithms
Authors: Tinkham Wade T. , Huang Hongyu , Smith Alistair M. S. , Shrestha Rupesh , Falkowski Michael J. , Hudak Andrew T. , Link Timothy E. , Glenn Nancy F. , Marks Danny G
Published: March 2011

With the progression of LiDAR (Light Detection and Ranging) towards a mainstream resource management tool, it has become necessary to understand how best to process and analyze the data. While most ground surface identification algorithms remain proprietary and have high purchase costs; a few are openly available, free to use, and are supported by published results. Two of the latter are the multiscale curvature classification and the Boise Center Aerospace Laboratory LiDAR (BCAL) algorithms. This study investigated the accuracy of these two algorithms (and a combination of the two) to create a digital terrain model from a raw LiDAR point cloud in a semi-arid landscape. Accuracy of each algorithm was assessed via comparison with >7,000 high precision survey points stratified across six different cover types. The overall performance of both algorithms differed by only 2%; however, within specific cover types significant differences were observed in accuracy. The results highlight the accuracy of both algorithms across a variety of vegetation types, and ultimately suggest specific scenarios where one approach may outperform the other. Each algorithm produced similar results except in the ceanothus and conifer cover types where BCAL produced lower errors.
A Reliable Energy-Efficient Multi-Level Routing Algorithm for Wireless Sensor Networks Using Fuzzy Petri Nets
Authors: Yu Zhenhua , Fu Xiao , Cai Yuanli , Vuran Mehmet C.
Published: March 2011

A reliable energy-efficient multi-level routing algorithm in wireless sensor networks is proposed. The proposed algorithm considers the residual energy, number of the neighbors and centrality of each node for cluster formation, which is critical for well-balanced energy dissipation of the network. In the algorithm, a knowledge-based inference approach using fuzzy Petri nets is employed to select cluster heads, and then the fuzzy reasoning mechanism is used to compute the degree of reliability in the route sprouting tree from cluster heads to the base station. Finally, the most reliable route among the cluster heads can be constructed. The algorithm not only balances the energy load of each node but also provides global reliability for the whole network. Simulation results demonstrate that the proposed algorithm effectively prolongs the network lifetime and reduces the energy consumption.
Implementation of a Synchronized Oscillator Circuit for Fast Sensing and Labeling of Image Objects
Authors: Kowalski Jacek , Strzelecki Michal , Kim Hyongsuk
Published: March 2011

We present an application-specific integrated circuit (ASIC) CMOS chip that implements a synchronized oscillator cellular neural network with a matrix size of 32 × 32 for object sensing and labeling in binary images. Networks of synchronized oscillators are a recently developed tool for image segmentation and analysis. Its parallel network operation is based on a “temporary correlation” theory that attempts to describe scene recognition as if performed by the human brain. The synchronized oscillations of neuron groups attract a person’s attention if he or she is focused on a coherent stimulus (image object). For more than one perceived stimulus, these synchronized patterns switch in time between different neuron groups, thus forming temporal maps that code several features of the analyzed scene. In this paper, a new oscillator circuit based on a mathematical model is proposed, and the network architecture and chip functional blocks are presented and discussed. The proposed chip is implemented in AMIS 0.35 mm C035M-D 5M/1P technology. An application of the proposed network chip for the segmentation of insulin-producing pancreatic islets in magnetic resonance liver images is presented.
A QoS-Guaranteed Coverage Precedence Routing Algorithm for Wireless Sensor Networks
Authors: Jiang Joe-Air , Lin Tzu-Shiang , Chuang Cheng-Long , Chen Chia-Pang , Sun Chin-Hong , Juang Jehn-Yih , Lin Jiun-Chuan , Liang Wei-Wen
Published: March 2011

For mission-critical applications of wireless sensor networks (WSNs) involving extensive battlefield surveillance, medical healthcare, etc., it is crucial to have low-power, new protocols, methodologies and structures for transferring data and information in a network with full sensing coverage capability for an extended working period. The upmost mission is to ensure that the network is fully functional providing reliable transmission of the sensed data without the risk of data loss. WSNs have been applied to various types of mission-critical applications. Coverage preservation is one of the most essential functions to guarantee quality of service (QoS) in WSNs. However, a tradeoff exists between sensing coverage and network lifetime due to the limited energy supplies of sensor nodes. In this study, we propose a routing protocol to accommodate both energy-balance and coverage-preservation for sensor nodes in WSNs. The energy consumption for radio transmissions and the residual energy over the network are taken into account when the proposed protocol determines an energy-efficient route for a packet. The simulation results demonstrate that the proposed protocol is able to increase the duration of the on-duty network and provide up to 98.3% and 85.7% of extra service time with 100% sensing coverage ratio comparing with LEACH and the LEACH-Coverage-U protocols, respectively.
Resistive Oxygen Gas Sensors for Harsh Environments
Authors: Moos Ralf , Izu Noriya , Rettig Frank , Reiß Sebastian , Shin Woosuck , Matsubara Ichiro
Published: March 2011

Resistive oxygen sensors are an inexpensive alternative to the classical potentiometric zirconia oxygen sensor, especially for use in harsh environments and at temperatures of several hundred °C or even higher. This device-oriented paper gives a historical overview on the development of these sensor materials. It focuses especially on approaches to obtain a temperature independent behavior. It is shown that although in the past 40 years there have always been several research groups working concurrently with resistive oxygen sensors, novel ideas continue to emerge today with respect to improvements of the sensor response time, the temperature dependence, the long-term stability or the manufacture of the devices themselves using novel techniques for the sensitive films. Materials that are the focus of this review are metal oxides; especially titania, titanates, and ceria-based formulations.
Glucose Sensing by Time-Resolved Fluorescence of Sol-Gel Immobilized Glucose Oxidase
Authors: Esposito Rosario , Della Ventura Bartolomeo , De Nicola Sergio , Altucci Carlo , Velotta Raffaele , Mita Damiano Gustavo , Lepore Maria
Published: March 2011

A monolithic silica gel matrix with entrapped glucose oxidase (GOD) was constructed as a bioactive element in an optical biosensor for glucose determination. Intrinsic fluorescence of free and immobilised GOD was investigated in the visible range in presence of different glucose concentrations by time-resolved spectroscopy with time-correlated single-photon counting detector. A three-exponential model was used for analysing the fluorescence transients. Fractional intensities and mean lifetime were shown to be sensitive to the enzymatic reaction and were used for obtaining calibration curve for glucose concentration determination. The sensing system proposed achieved high resolution (up to 0:17 mM) glucose determination with a detection range from 0:4 mM to 5 mM.
On Prolonging Network Lifetime through Load-Similar Node Deployment in Wireless Sensor Networks
Authors: Li Qiao-Qin , Gong Haigang , Liu Ming , Yang Mei , Zheng Jun
Published: March 2011

This paper is focused on the study of the energy hole problem in the Progressive Multi-hop Rotational Clustered (PMRC)-structure, a highly scalable wireless sensor network (WSN) architecture. Based on an analysis on the traffic load distribution in PMRC-based WSNs, we propose a novel load-similar node distribution strategy combined with the Minimum Overlapping Layers (MOL) scheme to address the energy hole problem in PMRC-based WSNs. In this strategy, sensor nodes are deployed in the network area according to the load distribution. That is, more nodes shall be deployed in the range where the average load is higher, and then the loads among different areas in the sensor network tend to be balanced. Simulation results demonstrate that the load-similar node distribution strategy prolongs network lifetime and reduces the average packet latency in comparison with existing nonuniform node distribution and uniform node distribution strategies. Note that, besides the PMRC structure, the analysis model and the proposed load-similar node distribution strategy are also applicable to other multi-hop WSN structures.
A Review of Non-Invasive Techniques to Detect and Predict Localised Muscle Fatigue
Authors: Al-Mulla Mohamed R. , Sepulveda Francisco , Colley Martin
Published: March 2011

Muscle fatigue is an established area of research and various types of muscle fatigue have been investigated in order to fully understand the condition. This paper gives an overview of the various non-invasive techniques available for use in automated fatigue detection, such as mechanomyography, electromyography, near-infrared spectroscopy and ultrasound for both isometric and non-isometric contractions. Various signal analysis methods are compared by illustrating their applicability in real-time settings. This paper will be of interest to researchers who wish to select the most appropriate methodology for research on muscle fatigue detection or prediction, or for the development of devices that can be used in, e.g., sports scenarios to improve performance or prevent injury. To date, research on localised muscle fatigue focuses mainly on the clinical side. There is very little research carried out on the implementation of detecting/predicting fatigue using an autonomous system, although recent research on automating the process of localised muscle fatigue detection/prediction shows promising results.
Design and Development of a Run-Time Monitor for Multi-Core Architectures in Cloud Computing
Authors: Kang Mikyung , Kang Dong-In , Crago Stephen P. , Park Gyung-Leen , Lee Junghoon
Published: March 2011

Cloud computing is a new information technology trend that moves computing and data away from desktops and portable PCs into large data centers. The basic principle of cloud computing is to deliver applications as services over the Internet as well as infrastructure. A cloud is a type of parallel and distributed system consisting of a collection of inter-connected and virtualized computers that are dynamically provisioned and presented as one or more unified computing resources. The large-scale distributed applications on a cloud require adaptive service-based software, which has the capability of monitoring system status changes, analyzing the monitored information, and adapting its service configuration while considering tradeoffs among multiple QoS features simultaneously. In this paper, we design and develop a Run-Time Monitor (RTM) which is a system software to monitor the application behavior at run-time, analyze the collected information, and optimize cloud computing resources for multi-core architectures. RTM monitors application software through library instrumentation as well as underlying hardware through a performance counter optimizing its computing configuration based on the analyzed data.
Fiber Optic Sensors for Structural Health Monitoring of Air Platforms
Authors: Guo Honglei , Xiao Gaozhi , Mrad Nezih , Yao Jianping
Published: March 2011

Aircraft operators are faced with increasing requirements to extend the service life of air platforms beyond their designed life cycles, resulting in heavy maintenance and inspection burdens as well as economic pressure. Structural health monitoring (SHM) based on advanced sensor technology is potentially a cost-effective approach to meet operational requirements, and to reduce maintenance costs. Fiber optic sensor technology is being developed to provide existing and future aircrafts with SHM capability due to its unique superior characteristics. This review paper covers the aerospace SHM requirements and an overview of the fiber optic sensor technologies. In particular, fiber Bragg grating (FBG) sensor technology is evaluated as the most promising tool for load monitoring and damage detection, the two critical SHM aspects of air platforms. At last, recommendations on the implementation and integration of FBG sensors into an SHM system are provided.
Fabrication of a Flexible Micro Temperature Sensor for Micro Reformer Applications
Authors: Lee Chi-Yuan , Lin Chien-Hen , Lo Yi-Man
Published: March 2011

Micro reformers still face obstacles in minimizing their size, decreasing the concentration of CO, conversion efficiency and the feasibility of integrated fabrication with fuel cells. By using a micro temperature sensor fabricated on a stainless steel-based micro reformer, this work attempts to measure the inner temperature and increase the conversion efficiency. Micro temperature sensors on a stainless steel substrate are fabricated using micro-electro-mechanical systems (MEMS) and then placed separately inside the micro reformer. Micro temperature sensors are characterized by their higher accuracy and sensitivity than those of a conventional thermocouple. To the best of our knowledge, micro temperature sensors have not been embedded before in micro reformers and commercial products, therefore, this work presents a novel approach to integrating micro temperature sensors in a stainless steel-based micro reformer in order to evaluate inner local temperature distributions and enhance reformer performance.
Sustainability Assessment of a Biorefinery Complex in Thailand
Authors: Gheewala Shabbir H. , Bonnet Sébastien , Prueksakorn Kritana , Nilsalab Pariyapat
Published: March 2011

In this paper, a biorefinery complex in Thailand was assessed vis-à-vis sustainability. The complex studied includes plantations of sugarcane and a biorefinery system composed of several units including, a sugar mill, power plant, ethanol factory and fertilizer plant. The assessment aimed at evaluating the environmental and socio-economic implications relating to molasses-based ethanol production and use, and maximized utilization of the biomass materials produced as part of the biorefinery complex. Global warming potential, human development index and total value added are the three indicators that were selected to perform the assessment. The results obtained revealed that the maximization of biomass utilization at the level of the biorefinery complex provide greenhouse gases emissions reduction benefits, enhanced living conditions for sugarcane farmers and employees of the biorefinery, and economic benefits, particularly with regard to profit and income generation. These results could serve as a first step to further improve and design indicators for sustainability assessment of biomass utilization.
Long Time Behaviour on a Path Group of the Heat Semi-group Associated to a Bilaplacian
Authors: Leandre Remi
Published: March 2011

We show that in long-time the heat semi-group on a path group associated to a Bilaplacian on the group tends to the Haar distribution on a path group.
Monochrome Symmetric Subsets in Colorings of Finite Abelian Groups
Authors: Zelenyuk Yuliya
Published: March 2011

A subset S of a group G is symmetric if there is an element g є G such that gS-1g = S. We study some Ramsey type functions for symmetric subsets in finite Abelian groups.
From Toxins Targeting Ligand Gated Ion Channels to Therapeutic Molecules
Authors: Nasiripourdori Adak , Taly Valérie , Grutter Thomas , Taly Antoine
Published: March 2011

Ligand-gated ion channels (LGIC) play a central role in inter-cellular communication. This key function has two consequences: (i) these receptor channels are major targets for drug discovery because of their potential involvement in numerous human brain diseases; (ii) they are often found to be the target of plant and animal toxins. Together this makes toxin/receptor interactions important to drug discovery projects. Therefore, toxins acting on LGIC are presented and their current/potential therapeutic uses highlighted.
Re-Assembled Botulinum Neurotoxin Inhibits CNS Functions without Systemic Toxicity
Authors: Ferrari Enrico , Maywood Elizabeth S. , Restani Laura , Caleo Matteo , Pirazzini Marco , Rossetto Ornella , Hastings Michael H. , Niranjan Dhevahi , Schiavo Giampietro , Davletov Bazbek
Published: March 2011

The therapeutic potential of botulinum neurotoxin type A (BoNT/A) has recently been widely recognized. BoNT/A acts to silence synaptic transmission via specific proteolytic cleavage of an essential neuronal protein, SNAP25. The advantages of BoNT/A-mediated synaptic silencing include very long duration, high potency and localized action. However, there is a fear of possible side-effects of BoNT/A due to its diffusible nature which may lead to neuromuscular blockade away from the injection site. We recently developed a “protein-stapling” technology which allows re-assembly of BoNT/A from two separate fragments. This technology allowed, for the first time, safe production of this popular neuronal silencing agent. Here we evaluated the re-assembled toxin in several CNS assays and assessed its systemic effects in an animal model. Our results show that the re-assembled toxin is potent in inhibiting CNS function at 1 nM concentration but surprisingly does not exhibit systemic toxicity after intraperitoneal injection even at 200 ng/kg dose. This shows that the re-assembled toxin represents a uniquely safe tool for neuroscience research and future medical applications.
Les sociétés françaises de services et d'ingénierie en informatique, historique et perspectives
Authors: Horaist Jacques
Published: March 2011

French computer service and software engineering companies, background and outlook,

by Jacques Horaist.

The importance of the French computer service and software engineering companies lies not in their percentage of the national turnover, which is modest, but rather in their dynamic outlook and in the impact of their activities. In this respect they are a fine example of the "developed tertiary sector" in which much hope is stored, particularly with regard to generating employment.

The technological progress which has been maintained over the last thirty years has meant that costs of equipments have been kept down, with the result that companies can afford to install more and more hardware and consequently increase their need for services. To date, as is demontrasted in the first part of the article, the French computer service companies owe their development mainly to software engineering and userdesigned software based on their creativity, the fruits of their research, the quality of their staff and sound financial management. The fact that they have come to occupy the number two place on the world market is proof of their ability and of the soundness of their approach In recent years, the increasing demand for mass produced hardware and software has led to the industrialization of software production. The new software products are faring very well in France under the driving force of Amercan companies-mainly the hardware producers themselves. The text goes on to point ou that, rather than jumping headlong into this type of production, which involves new business methods, the French computer service companies prefer to consolidate their position. The outlook for demand, taking into consideration foreseeable technological advances, seems to point to a strong trend towards customdesigned applications, with a high intellectual content, particularly in the realm of the data processing networks. But such development will be irregular because of force of habit and the desire among certain users to get the most out of their past investments.

If they are to make the most of the situation and maintain their lead, the French computer service and software engineering companies will have, in conjunction with their public or private partners, to find a way round the problems of setting up a market on the European scale, financing their research and training their staff.
Une méthode d'analyse interne des modèles macro-économétriques multinationaux : présentation et application au modèle de R.C. Fair
Authors: Laffargue Jean-Pierre
Published: March 2011

An internal analysis procedure

of macroeconometric multinational models:

presentation and application to the R.C. Fair's model,

by Jean-Pierre Laffargue.

This paper introduces a new evaluation procedure of multinational models and gives an application to the multi-country system which has been built by R.C. Fair. The first step is to modify the numerical values of parameters in order to make all the countne's structures similar (i.e. only differing in size). Then the consequences of economic policy can be allocated between a world and a differential component. These components are independent and it is easy to give them an economic interpretation. In the following steps, countries' structural specificities are progressively remtroduced. Simulations show how these peculiarities change the results which have been obtained in their absence. These modifications then receive economic interpretations.
La concurrence dans le commerce de détail en France
Authors: Écalle François
Published: March 2011

Competition in the retail trade in France,

by François Ecalle.

First of all this article describes certain characteristics of competition in the retail trade which are inherent in the very nature of the activity. It stresses the fact that poor consumer information and the differences between the services provided do not necessarily prevent the free play of competition; they just temper it and keep it from being too harsh.

It goes on to give the results for the sector of a survey of concentration measured by "arrondissement", showing that, in general concentration is quite limited, although in certain zones or sectors the levels were higher.

The effect of the barriers set up by the French legislation on new commercial installations (the Royer Law) is also noted. The aim and provisions of this law might have led us to expect a sharp drop in the number of new supermarkets starting up. But it does not seem to have been enforced too harshly. Here again, big differences can be seen from one place to another and from one product to another.

Finally, certain indicators are mentioned suggesting that competition has been generally intense in the retail trade in recent years. The legislation does threaten to check it, however, without any real economic justification, in numerous regions.
Le Japon : succès présents, contraintes futures
Authors: Broclawski Jean-Pierre
Published: March 2011

Japan: present successes, futures constraints, by Jean-Pierre Broclawski.

The successes obtained by Japan in the recovery phase of the world economy which began in spring 1983 concretized the industrial restructuring efforts undertaken since the first oil crisis. The performances realized by the Japanese economy both concerning growth and the great macroeconomic equilibriums were perceived abroad first of all by its trade surpluses essentially in manufactured goods and then by the massive outflow of long terme capital still widely privileging portfolio movements. In the middle of the 1 980s the record surpluses of the trade balance are reinforcing Japan's status as the mam creditor of the international monetary system at a time when the United States are becoming debtors to the rest of the world and when the financial situation of the Opep is rapidly deteriorating.

However the perenniality of this positive balance linked with the capacity of adaptation of Japanese production to the evolution of the international environment is not entirely ensured in the medium term. Japan will have to face up to the threats hanging over the freedom of trade and it will have to answer the ever sharper criticisms of its main partners, in the first place the United States. The passage to a model of growth founded on domestic demand and no longer centered on exports is a necessity proclaimed very officially by the Mayekawa report transmitted to the Prime Minister Mr. Nakasone on the eve of the Tokyo Summit. But this priority given to expansion of the domestic components of demand constitutes a particularly ambitious objective since the Japan's population is becoming older and older and since the amplitude of the national debt is rather inciting the government to continue applying a restrictive budgetary policy.
Réglementation et concurrence : quelques éléments de théorie économique
Authors: Encaoua David
Published: March 2011

Réglementation et concurrence : quelques éléments de théorie économique, par David Encaoua.

Ce document présente des éléments de théorie économique permettant d'éclairer le débat autour du thème de la déréglementation économique. L'accent est mis sur les situations de concurrence inefficace ou/et impraticable qui sont censées caractériser le fonctionnement de nombreuses activités : télécommunications, transports aériens, transports routiers... Jusqu'au milieu des années 1960, il était traditionnellement admis que les défaillances des mécanismes de marché dues à ces imperfections de la concurrence justifiaient une régulation par les pouvoirs publics en termes de contrôle des prix et de la structure de l'offre. Mais à partir de cette date, de nombreuses critiques sont apparues aux Etats-Unis, mettant l'accent soit sur les défaillances des processus réglementaires eux-mêmes, soit sur le caractère erroné des prémisses à partir desquelles se justifiait la réglementation.

Le document développe plus précisément ce deuxième type de critiques en analysant la théorie des marchés contestables qui se présente comme un nouveau paradigme d'analyse de la concurrence. La question centrale qui est traitée est alors la suivante : l'existence d'une menace d'entrée de concurrents potentiels et le dépassement des frontières d'activités définissant un monopole naturel suivant l'apparition de nouvelles technologies peuvent-elles, créer une pression suffisante pour que la régulation par les forces du marché conduise à des résultats collectivement satisfaisants ? La situation du monopole naturel multi- produits ne comportant pas de coûts fixes irréversibles est examinée en détail, notamment à travers le problème de l'allocation des coûts.

La dernière partie du texte a pour objet d'examiner dans quelle mesure les expériences récentes de déréglementation aux Etats-Unis se sont avérées conformes aux prédictions de la théorie des marchés contestables, en analysant les situations respectives des transports aériens et des télécommunications.
Les dénationalisations britanniques : objectifs et réalisations
Authors: Santini Jean-Jacques
Published: March 2011

Privatization in the United Kingdom aims and achievements, by Jean-Jacques Santini.

The policy of privatization which the United Kingdom embarked on in 1979 is far-reaching enough to constitute an unprecedented experience which most of the industrialized nations are observing with interest.

After a short summary of the main development in the british public sector from 1945 to the present days, this paper attempts to analyse the privatization policy which Mrs Thatcher's government is carrying out in terms of its aims and achievements.

The process is far from complete at the moment and is even likely to speed up over the next three years, furthermore its impact cannot always be appreciated in the short term, so the conclusions which are drawn remain incomplete. It would appear, nevertheless, that the main objectives of the British Government — improving the performance of public sector firms, reducing State influence on the economy, relaxing budgetary constraints, developing popular investment and employee share schemes and reducing the power of the unions — have been accomplished to a satisfactory extent.

Although certain questions remain to be answered, the British privatization policy, which has been reasonably empirical in its approach, appears successful enough to be considered as an example to be followed by some other countries.

JEL: Classification number 614.
Econométrie de l'investissement et enquêtes de conjoncture
Authors: Poret Pierre
Published: March 2011

Econometrics of investment and business surveys,

by Pierre Poret.

The usual model of the accelerator (which relates capital to production) does not provide for the measurement of the role played by Keynesian demand constraints, which can limit production just as easily as insufficient returns.

At most, this near-accounting equation we find in most of the major macro-econometric forecasting models can tell us something about the production function selected. If we wish to conserve them, however, we can seek to improve them by reconsidering the supposed characteristics of the production function. In this way we show how business surveys shed an original and useful light on the possible deformations of the production function and on depreciation behaviours.

Models based on more than one school (Keynesian, classical, etc.) in which market constraint is unduly represented by production are theoretically biassed towards the acceptation of the Keynesian hypothesis. We therefore propose another formulation of the Keynesian accelerator, based on balances of opinion from surveys and on predictable demand trends, and allowing quite a rich description of behaviours (taking into account past anticipation errors and demand uncertainties). Finally, we present estimations made with more general models based on two schools (Keynesian and classical) and compare these estimations with the results of surveys on the number of investors with financial constraints. Both approaches showd the same trend: the effect of profitability has increased on average since the mid-seventies.

This study also brings out the threefold value of business survey results: they bring additional information to shed more light on the meaning of statistics or quantitative results, they provide direct knowledge of anticipations and give "leading indicators" which can be integrated into econometric modelling.
Quelques propositions d'indicateurs d'analyse du commerce bilatéral
Authors: Mathis Jean
Published: March 2011

Quelques propositions d'indicateurs d'analyse du commerce bilatéral,

par Jean Mathis.

L'analyse du commerce extérieur bilatéral nécessite l'utilisation d'indicateurs. Ceux-ci sont passés en revue en partant des plus simples pour aboutir, par des combinaisons successives, à des formulations plus riches de sens économique.

L'article cherche à répondre à deux questions. Quels sont, tout d'abord, les indicateurs qui permettent d'analyser les spécificités d'une relation bilatérale (entre deux pays ou deux zones) au-delà des caractéristiques globales du commerce extérieur des partenaires ? Les indicateurs habituellement utilisés ne sont-ils pas, d'autre part, entachés de biais statistiques ?

Les critiques formulées et les solutions proposées sont illustrées par une analyse du commerce extérieur des grands pays industriels.
La réorientation du système fiscal britannique (1979-1986)
Authors: Santini Jean-Jacques
Published: March 2011

The reorientation of the british tax system (1979-1986),

by Jean-Jacques Santini.

A number of studies carried out in the United Kingdom in the 1970s seemed to indicate that the British tax system led to distortions in resource allocation which were prejudicial to the operations of the economic system.

In the light of these findings, when Mrs Thatcher's government came to power in 1979 it immediately brought in a tax reform policy. The measures included in this policy, which were numerous and often far- reaching, affected taxes on households as well as company taxation.

The study presented here describes the various measures complemented and attempts to judge their possible impact on the British economic system. Although it is still difficult to draw up a conclusive report on the results of this tax reform policy (which is not yet complete, several of the projected reforms having not yet been implemented, and which includes structural alterations which are slow to alter behaviour), three conclusions seem to stand out:

the réorientation of the fiscal system since 1979 has been a major one, as can be seen from the change in the spread of taxation over households and companies on the one hand and the respective weight of direct and indirect taxation on the other;

the short-term impact of the reforms introduced has sometimes been quite marked, whether positive (as in the case of the investment tax reform carried out between 1984 and 1986) or negative (the increase in direct taxation introduced in 1979);

generally speaking, the British tax system seems better oriented now than in 1979 with regard to the achievement of economic policy objectives: the incentive to work has been increased, financial savings should progress and be better oriented towards productive investment, the quality of investment should improve and employment should be encouraged.

JEL: 321
Une analyse du processus de désinflation
Authors: Morin Pierre
Published: March 2011

Une analyse du processus de désinflation, par Pierre Morin.

Le succès des politiques de désinflation appelle un examen attentif de ses causes. Il est mené ici à l'aide des outils fournis par les analyses quantitatives : équations, maquettes, modèles. L'article aborde successivement trois points. Il rend compte des propriétés essentielles des boucles prix-salaires des modèles. Il examine attentivement les leçons des travaux économétriques. Il quantifie, si c'est possible, la contribution des diverses causes envisageables des désinflations françaises, — cas particulier mais qui a ses singularités — , et de la zone Ocdé... Les difficultés que l'on rencontre à tous les niveaux y sont précisées : insatisfaction sur les variables explicatives pertinentes, doutes sur les propriétés à long terme souhaitables, certitudes sur le caractère réducteur des maquettes, constituant pourtant le seul outil évitant un degré de complexité non-maîtrisable.

Plusieurs conclusions apparaissent néanmoins. Ainsi l'importance de l'inflation et de la désinflation importée ne suffit pas pour simuler la réalité du mouvement des prix et l'examen d'un ensemble agrégé de pays conduit à infléchir la pondération des causes apparue pour un seul.