Separate Nodes Research Articles

In vitro shoot induction and multiplication from nodal segments of adult Ginkgo biloba plants

The in vitro performance of herbaceous and woody nodal segments from adult plants and the effect of hydrolyzed casein (HC 500 mg L-1), kinetin (KIN; 6-furfurylaminopurine 0.46 and 4.65 µM) and activated charcoal (AC 1.5 g L-1) were evaluated upon new shoots induction and development, and to establish a system of in vitro propagation from adult plants of Ginkgo biloba. Woody nodal segments did not produce axillary shoots and presented 100% of bacterial and fungal contamination in culture. However, nodal segments from herbaceous shoots were successfully disinfected and displayed high in vitro morphogenic capacity. The HC was essential for the axillary shoots induction and further multiplication, stimulating shoot formation in 85% of the cultured nodal segments and multiple shoots induction in 35% of them at establishment stage. During the multiplication stage, 66.6% of propagules formed new shoots and 33.3% of them formed multiple shoots when cultured with HC. The KIN and AC inhibited the organogenic process in ginkgo. Two distinct patterns of sprouts development were observed in vitro, similar to what occurs in vivo: 1) short shoots with crowded internodes and expansion of only a few leaves and slow growth; 2) long shoots with separated nodes and marked apical growth. This is the first report of multiple shoots in vitro formation in nodal segments obtained from adult plants of Ginkgo biloba.

Design and Research of Low-Energy Consumption Sensor Nodes in a Smart-Scene System

This paper introduces an application of wireless sensor network based on the ZigBee -- the Smart-Scene system. In-depth analysis of factors of invalid power consumption, a functional separated sink node is designed and a DPM (Dynamic Power Management) schema of dynamic node based on event-driven is proposed. The schema is used in Smart-Scene system and the experimental results indicate it is high feasibility and reduce energy consumption. This method will become an effective solution for wireless sensor network.

The Wiring Economy Principle for Designing Inference Networks

The wiring economy principle in neuroscience has explained many experimentally observed properties of neuronal networks by asserting the need to keep the axons and dendrites that connect neurons small in length. Just like neuronal networks, many distributed systems are physical constructs that incur deployment and maintenance costs for their communication infrastructure. Taking wiring economy as a design goal for engineering systems that perform distributed coordination and inference, this paper formulates and studies the tradeoff between performance and wiring cost. It is shown that separated communication topology design and physical node placement yields optimal design. Designing optimal networks is shown to be NP-complete. The natural relaxation to the integer network design problem is shown to be a reverse convex program. Small optimal networks are computed. Optimally placed random network topologies are demonstrated to have good performance.

Quantum Simulation via Filtered Hamiltonian Engineering: Application to Perfect Quantum Transport in Spin Networks

We propose a method for Hamiltonian engineering that requires no local control but only relies on collective qubit rotations and field gradients. The technique achieves a spatial modulation of the coupling strengths via a dynamical construction of a weighting function combined with a Bragg grating. As an example, we demonstrate how to generate the ideal Hamiltonian for perfect quantum information transport between two separated nodes of a large spin network. We engineer a spin chain with optimal couplings starting from a large spin network, such as one naturally occurring in crystals, while decoupling all unwanted interactions. For realistic experimental parameters, our method can be used to drive almost perfect quantum information transport at room temperature. The Hamiltonian engineering method can be made more robust under decoherence and coupling disorder by a novel apodization scheme. Thus, the method is quite general and can be used to engineer the Hamiltonian of many complex spin lattices with different topologies and interactions.

Cooperative Carrier Signaling: Harmonizing Coexisting WPAN and WLAN Devices

The unlicensed ISM spectrum is getting crowded by wireless local area network (WLAN) and wireless personal area network (WPAN) users and devices. Spectrum sharing within the same network of devices can be arbitrated by existing MAC protocols, but the coexistence between WPAN and WLAN (e.g., ZigBee and WiFi) remains a challenging problem. The traditional MAC protocols are ineffective in dealing with the disparate transmit-power levels, asynchronous time-slots, and incompatible PHY layers of such heterogeneous networks. Recent measurement studies have shown moderate-to-high WiFi traffic to severely impair the performance of coexisting ZigBee. We propose a novel mechanism, called cooperative carrier signaling (CCS), that exploits the inherent cooperation among ZigBee nodes to harmonize their coexistence with WiFi WLANs. CCS employs a separate ZigBee node to emit a carrier signal (busy tone) concurrently with the desired ZigBee's data transmission, thereby enhancing the ZigBee's visibility to WiFi. It employs an innovative way to concurrently schedule a busy tone and a data transmission without causing interference between them. We have implemented and evaluated CCS on the TinyOS/MICAz and GNURadio/USRP platforms. Our extensive experimental evaluation has shown that CCS reduces collision between ZigBee and WiFi by 50% for most cases, and by up to 90% in the presence of a high-level interference, all at negligible WiFi performance loss.

Emergence of network features from multiplexity.

Many biological and man-made networked systems are characterized by the simultaneous presence of different sub-networks organized in separate layers, with links and nodes of qualitatively different types. While during the past few years theoretical studies have examined a variety of structural features of complex networks, the outstanding question is whether such features are characterizing all single layers, or rather emerge as a result of coarse-graining, i.e. when going from the multilayered to the aggregate network representation. Here we address this issue with the help of real data. We analyze the structural properties of an intrinsically multilayered real network, the European Air Transportation Multiplex Network in which each commercial airline defines a network layer. We examine how several structural measures evolve as layers are progressively merged together. In particular, we discuss how the topology of each layer affects the emergence of structural properties in the aggregate network.

Defending Sybil attack using Associate Membership method in Distributed P2P Network

The Peer-to-peer networks popularity is increasing day by day for its resource allocation system like file sharing, Skype etc .The system is extremely fast because of its fully decentralized nature. Although this is efficient system but this system’s security is vulnerable and can be attacked anytime by attackers. This paper describes P2P’s most challenging threat Sybil attack. Generally Sybil attack is defined as an attack by a malicious user who creates multiple identities and act as separate and real nodes. These fake nodes are called Sybil nodes. After creating these fake IDs, malicious user can control the network by controlling the nodes which contains resources. They can also change the resources and can attack node’s routing table, they can damage node’s communication on the network. This paper describes possible solutions against this attack by using existing SyMon protocol with our proposed “Associate membership” method .By implementing the proposed model performance will increase to defense against Sybil attack.

An Adaptive Distance-based Resource Allocation Scheme for Interdependent Tasks in Mobile Ad Hoc Computational Grids

Two key components contribute to task completion time: execution cost and communication cost. The communication cost is induced by data transfers between tasks residing on separate nodes. The communication is always expensive and unreliable in mobile ad hoc Grids and therefore plays a critical role in application performance. To reduce communication cost, interdependent tasks are allocated to nodes located close to one another. However, once the tasks have been allocated, nodes can move within a Grid. The movement of nodes within a Grid may result in multi-hop communication between nodes executing dependent tasks. In order to deal with node mobility within a Grid, an effective resource allocation scheme is required, but the design of such a scheme for mobile ad hoc computational Grids is challenging due to the constrained communication environment, node mobility, and infrastructure-less network environment. In this paper, we have developed an adaptive and distance-based resource allocation scheme which takes into account the characteristics of an application and nodes and applies migration heuristics to address the local node mobility problem. The scheme is validated in a simulated environment using various workloads and parameters. DOI: http://dx.doi.org/10.5755/j01.itc.41.4.877

A Self-Organizing Feature Map (SOFM) model based on aggregate-ordering of local color vectors according to block similarity measures

Self-Organizing Feature Maps (SOFMs) are extensively used for dimensionality reduction and rendering of inherent data structures. A novel model of a SOFM based on the notion of aggregate/reduced ordering (R-ordering) of vector sets is proposed and applied to the segmentation of color images. The so-called Cross-Order Distance Matrix is defined in order to measure the similarity between local histograms corresponding to ordered sets of color vectors. Color images are regarded as two-dimensional (2-D) vector fields. Basic image processing algorithms are modified since color is represented as a vector instead of a scalar gray level variable. Operators utilizing several distance and similarity measures are adopted in order to quantify the color distribution within a sliding window. The proposed window-based SOFM uses sets of one, two and more color vectors in order to approximate local color distributions within sliding windows. Each set represents a separate node of the SOFM that is trained according to a sequence of ordered input sets of color vectors. A 3×3 window is used to capture color components in uniform color space (L⁎u⁎v⁎). The color vectors within the sliding window are R-ordered. The neuron featuring the smallest aggregated distance (similarity) is activated during training. Segmentation results suggest that clustered nodes represent populations of pixels in rather compact segments of the images featuring similar texture.

Range Detection Multicast Routing Protocol for Mobile Ad-Hoc Networks

Problem statement: Many efforts have been implemented towards the Group membership management on multicast routing in MANETs, but the difficulties associated with Group membership management are still existed. Approach: Maintaining endurance of Group Leader (GL) in multicasting routing has been a great challenge to all the protocol having been invented so far. Results: This study provides the RDMP algorithm for persistency of Group Leader within the group. Nodes perform very active in exchanging the Data and Control packet when they mobile within the transmission range. Range Detection Multicast Protocol (RDMP) focuses on dynamic topology of nodes and uses detection mechanism based on transmission range within the group. Instead of having a separate external node to monitor on Group leadership, a node within the transmission range acts as a Leadership Track Node (LTN), Group Leader manages the group member with the aid provided by LTN and thus control over head shared among them. LTN keeps track of mobility of Group Leader and send alert message when Group Leader moves out of Transmission range and also holds the list of address of all other Group Leader which are adjacent to it. Routing control packet and data packet are regulated with minimum control over head. Conclusion/Recommendations: Our simulation results under increasing group size demonstrate endurance of Group leader for longer period of time, joining delay for multicast group is very low, normalized control over head and minimizing number of hops in maintain average path length.

An embedded cohesive crack model for finite element analysis of quasi-brittle materials

This paper presents a numerical implementation of the cohesive crack model for the analysis of quasibrittle materials based on the strong discontinuity approach in the framework of the finite element method. A simple central force model is used for the stress versus crack opening curve. The additional degrees of freedom defining the crack opening are determined at the crack level, thus avoiding the need for performing a static condensation at the element level. The need for a tracking algorithm is avoided by using a consistent procedure for the selection of the separated nodes. Such a model is then implemented into a commercial program by means of a user subroutine, consequently being contrasted with the experimental results. The model takes into account the anisotropy of the material. Numerical simulations of well-known experiments are presented to show the ability of the proposed model to simulate the fracture of quasibrittle materials such as mortar, concrete and masonry.

The real other? Museum objects in digital contact networks

What can museum objects do when they are placed within a digital contact network – a system made up of reciprocally linked but otherwise separate nodes in which control and ownership of content lies with each location? What new connections are enabled through the placement of objects within this contact network and what are the new understandings that result? Dynamics of access, ownership and meaning change when museum collections are transformed into digital forms, in ways that require the reconceptualization of digital objects and their relational capacities. In theory and in practice, the ‘real’ and the digital object are often framed as disconnected and oppositional entities, a separation that hinders approaches to, and uses of, digital forms. Using examples of recent projects at the University of Cambridge Museum of Archaeology and Anthropology, and at the British Museum, it is argued that digital contact networks enable the unique qualities of digital objects to come to the fore, providing platforms for effective engagement and digital reciprocation.

LPA Stimulates the Phosphorylation of p130Cas via G i2 in Ovarian Cancer Cells

Ovarian cancer is the most deadly gynecological cancer, with previous studies implicating lysophosphatidic acid (LPA) in the progression of approximately 90% of all ovarian cancers. LPA potently stimulates the tyrosine phosphorylation of p130Cas, a scaffolding protein, which, upon phosphorylation, recruits an array of signaling molecules to promote tumor cell migration. Our work presented here identifies Gαi2 as the major G protein involved in tyrosine phosphorylation of p130Cas in a panel of ovarian cancer cells consisting of HeyA8, SKOV3, and OVCA429. Our results also indicate that the G12 family of G proteins that are also involved in LPA-mediated migration inhibits tyrosine phosphorylation of p130Cas. Using p130Cas siRNA, we demonstrate that p130Cas is a necessary downstream component of LPA Gαi2-induced migration and collagen-1 invasion of ovarian cancer cells. Considering the fact that LPA stimulates invasive migration through the coordination of multiple downstream signaling pathways, our current study identifies a separate unique signaling node involving p130Cas and Gαi2 in mediating LPA-mediated invasive migration of ovarian cancer cells.

An effective and robust two-phase resource allocation scheme for interdependent tasks in mobile ad hoc computational Grids

This paper addresses the problem of resource allocation to interdependent tasks in mobile ad hoc computational Grids. Dependencies between tasks imply that there can be heavy communication induced by data transfers between tasks executed on separate nodes. The communication in mobile ad hoc Grids is always expensive and unreliable, and therefore plays a critical role in application performance. There are several factors that contribute to communication cost. Unreliable and short-term connectivity can increase communication cost due to frequent failure and activation of links, and ineffective resource allocation can increase communication cost due to multi hop communication between dependent tasks. To reduce communication cost, an effective and robust resource allocation scheme is required. However, the design of such a scheme for mobile ad hoc computational Grids exhibits numerous difficulties due to the constrained communication environment, node mobility, and lack of pre-existing network infrastructure.In this paper, we propose a two-phase resource allocation scheme to reduce communication cost between dependent tasks. The scheme is divided into two phases. The first phase exploits the history of user mobility patterns to select nodes that provide long-term connectivity and the second phase takes into account the task and dependency types, and uses the distance information among the nodes selected in the first phase to reduce communication costs. The scheme is validated in a simulation environment using various workloads and parameters.

Sonographic characteristics of presumptively normal main axillary and superficial cervical lymph nodes in dogs

To evaluate the B-mode and Doppler ultrasonographic appearance of presumptively normal main axillary and large superficial cervical lymph nodes (MALNs and SCLNs, respectively) in adult dogs. 51 healthy adult dogs (data from 1 dog were not analyzed). For each dog, weight, distance from the cranial aspect of the first sternebra to the caudal aspect of the left ischiatic tuberosity, and thoracic height and width at the level of the xiphoid process were recorded. Via B-mode and Doppler ultrasonography, echogenic characteristics, size in relation to body size and weight, and vascular supply of the MALNs and the SCLNs were evaluated (1 SCLN in 1 dog was not ultrasonographically visible). Most MALNs were clearly margined, solitary, and ovoid; echopatterns were homogenous or cortical and hypo- to isoechoic, compared with surrounding soft tissues. Size measurements of MALNs correlated with dogs' body length, thoracic width and height, and body weight. Most SCLNs were clearly margined, fusiform, and hypoechoic (compared with surrounding soft tissues) with a cortical or homogenous echopattern. Size measurements of SCLNs correlated with dogs' body length, thoracic width and height, and body weight. In 50 of the 100 MALNs, an intranodal vascular supply was detected; in contrast, an intranodal vascular supply in SCLNs was detected infrequently. Results indicated that, in dogs, anatomically separate lymph nodes have different echogenic and vascular characteristics; body size (skeletal length, height, and width), along with body weight, were correlated with sizes of presumptively normal MALNs and SCLNs.

Role of imaging techniques in the TNM classification of non-small cell bronchogenic carcinoma

The Seventh Edition of the TNM classification for non-small cell bronchogenic carcinomas includes a series of changes in the T and M descriptor, in particular a re-classification of malignant pleural and pericardial effusions and of separated tumor nodes, new tumour size cut-off values and sub-divisions of the T1–T2 and M1 categories. We review these corrections that led to the changes in the staging system that affects stages II–III. Furthermore, we describe and illustrate the role of the different imaging techniques in tumour staging (CT, PET, PET–CT and MRI), highlighting their respective indications, advantages and disadvantages, as well their complementary function.

Differentiation of four indian aboriginal cattle populations revealed by SIR markers

Cattle are the most important livestock in India and play a pivotal role in agrarian economy. There are 34 recognized breeds of cattle and number of unexplored lesser known populations. The present study is a contribution towards determining genetic variation and understanding the relationship among four lesser known populations. A total of 194 unrelated DNA samples from three cattle populations of Orissa (Binjharpuri, Ghumsuri, Motu) and Hill cattle of Kumaun (Kumauni) were collected from respective breeding tracts. Genotyping was done with 23 bovine microsatellite markers as suggested by International Society for Animal Genetics (ISAG) and FAO (DAD-IS) on automated sequencer. The average observed heterozygosity in the four populations lie within the narrow range of 0.623 +/- 0.04 in Binjharpuri to 0.664 +/- 0.03 in Kumauni. Mean estimates of observed and expected heterozygosity over all loci and breeds were 0.651 +/- 0.02 and 0.720 +/- 0.01, respectively. In the overall population, the homozygote excess (F(IT)) of 0.132 +/- 0.03, was partly due to the genetic differentiation among breeds (F(ST) = 0.044 +/- 0.01) and, to a larger extent, to a significant homozygote excess within breeds (F(IS) = 0.094 +/- 0.03). The phylogenetic reconstruction from a UPGMA clustering based on Nei's Standard genetic distance yielded a tree with Binjharpuri and Ghumsuri on a single node and Motu and Kumauni on separate nodes. The most probable clustering detected by STRUCTURE in population was three. Binjharpuri and Ghumsuri animals were assigned to one cluster with high proportion of membership.

Approach-related left prefrontal EEG asymmetry predicts muted error-related negativity

In two studies, we used electroencephalography (EEG) to test whether approach-motivation-related brain activity would predict reduced sensitivity to negative outcomes. In both studies, participants (Study 1, N=26; Study 2, N=56) were first recorded for baseline EEG to measure approach-related left frontal EEG activity. They then completed either the color-naming Stroop task (Study 1) or the Multi-Source Interference Task (Study 2) to measure error-related negativity (ERN), an event-related potential that has been associated with aversive motivation and distress. In both studies, higher leftward frontal EEG asymmetry predicted reduced ERN amplitude. Hierarchical regression analyses of the separate frontal nodes that comprised the asymmetry score further showed that left frontal activity predicted reduced ERN amplitude whereas right frontal activity predicted greater ERN amplitude. Results have implications for understanding emotion and motivation and for understanding the personal resilience associated with approach motivated states.

Circular grid pattern based surface strain measurement system for sheet metal forming

A surface strain measurement system (XJTUSM) for sheet metal forming is developed based on close range industry photogrammetry. A circular grid pattern is electrochemically etched onto the surface of flat sheet metal before forming. As the sheet metal is pressed into a desired shape, these circular grid nodes are deformed into approximate elliptical shapes. Original images are then recorded from different photo stations using a single camera. The three-dimensional (3D) coordinates of these ellipse centers are reconstructed according to image processing technologies, which include noise reduction, adaptive thresholding, sub-pixel edge detection, least-square ellipse fitting, camera calibration, fast matching and reconstruction of grid nodes. Subsequently, a 3D grid generation procedure is performed to build the topology of separate grid nodes and the deformation gradient tensor is calculated. Finally, the surface strains are derived from the deformation gradient tensor and the forming limit diagram (FLD) is thus obtained. To evaluate the accuracy of the novel system, a tensile experiment was carried out, and the high-accuracy surface strain measurement system XJTUDIC was employed for comparison. The surface strains measured by two systems agree well. The XJTUSM system can be used to diagnose production problems, identify critical areas and/or verify the accuracy of numerical modeling.

Papel de las técnicas de imagen en la nueva clasificación TNM del carcinoma broncogénico no microcítico

The Seventh Edition of the TNM Classification for non-small cell bronchogenic carcinomas include a series of changes in the T and M descriptor, in particular a re-classification of malignant pleural and pericardial effusions and of separated tumour nodes, new tumour size cut-off values and sub-divisions of the T1-T2 and M1 categories. We review these corrections that led to the changes in the staging system that affects stages II-III. Furthermore, we describe and illustrate the role of the different imaging techniques in tumour staging (CT, PET, PET-CT and MRI), highlighting their respective indications, advantages and disadvantages, as well their complementary function.