Implementation Of Approximate Multiplier By Using 4:2 Compressors

Four duplication designs have been proposed using approximately 4: 2 compressors. Overall simulation results show that the proposed designs achieve a significant improvement in accuracy with reduced power and lag compared to previous preliminary designs. An image processing application is also presented to show the efficiency of the proposed designs. This report manages another planned approach to estimating complications. The results of the multiplier are modified midway to present the variable probability conditions. The unpredictability of the estimation justification for the collection of modified fractional elements fluctuates in light of the probability that they will occur. The suggested estimate is used in two variants of 16-bit multiples. The combined results revealed that two of the proposed multipliers reach 72% of the control reserve funds and 38%, individually, in contrast to the correct multiplier. They have better precision when differentiated from the harsh complications that exist. The average relative division numbers are as low as 7.6% and 0.02% for the proposed severe multipliers, which are better than previous work. The implementation of the proposed complications is clarified with an image produced by the application, where one of the proposed models achieves the most striking dazzling peak to the point of inversion

Bioremediation Of Dairy Wastewater Using Microalgae For The Production Of Biodiesel

This study describes the feasibility for treatment of dairy waste waters in batch cultures by using selected strains of green microalgae namely Chlorella vulgaris, Botryococcus braunii and a mixed algal culture in indoor and outdoor. The Biomass productivity peaked on the 6th day. Best results were observed in C. vulgaris strain in both indoor and outdoor studies with biomass productivity of 0.51g/L, chlorophyll concentration of 0.039mg/L and lipid yield of 0.030g/L in indoor cultures whereas 0.59g/L of biomass productivity, 0.045mg/L chlorophyll concentration and 0.035g/L lipid yields were obtained in outdoor studies.. Gas Chromatography mass Spectrophotometer (GC MS) analysis of the extracted lipids showed that major components in C.vulgaris and mixed algae were palmitic acid, staeric acid and oleic acid where as oleic acid was the major component in B.braunii and palmitic acid, staeric acid were also present in minor amounts

Salt-tolerant genes from halophytes are potential key players of salt tolerance in glycophytes

Crop productivity strongly depends on several biotic and abiotic factors. Salinity is one of the most important abiotic factors, besides drought, extreme temperatures, light and metal stress. The enhanced burden of secondary salinization induced through anthropogenic activities increases pressure on glycophytic crop plants. The recent isolation and characterization of salt tolerance genes encoding signaling components from halophytes, which naturally grow in high salinity, has provided tools for the development of transgenic crop plants with improved salt tolerance and economically beneficial traits. In addition understanding of the differences between glycophytes and halophytes with respect to levels of salinity tolerance is also one of the prerequisite to achieve this goal. Based on the recent developments in mechanisms of salt tolerance in halophytes, we will explore the potential of introducing salt tolerance by choosing the available genes from both dicotyledonous and monocotyledonous halophytes, including the salt overly sensitive system (SOS)-related cation/proton antiporters of plasma (NHX/SOS1) and vacuolar membranes (NHX), energy-related pumps, such as plasma membrane and vacuolar H+ adenosine triphosphatase (PM& V-H+ATPase), vacuolar H+ pyrophosphatases (V-H+PPase) and potassium transporter genes. Various halophyte genes responsible for other processes, such as crosstalk signaling, osmotic solutes production and reactive oxygen species (ROS) suppression, which also enhance salt tolerance will be described. In addition, the transgenic overexpression of halophytic genes in crops (rice, peanut, finger millet, soybean, tomato, alfalfa, jatropha, etc.) will be discussed as a successful mechanism for the induction of salt tolerance. Moreover, the advances in genetic engineering technology for the production of genetically modified crops to achieve the improved salinity tolerance under field conditions will also be discussed

Chick Embryo Partial Ischemia Model: A New Approach to Study Ischemia Ex Vivo

Background: Ischemia is a pathophysiological condition due to blockade in blood supply to a specific tissue thus damaging the physiological activity of the tissue. Different in vivo models are presently available to study ischemia in heart and other tissues. However, no ex vivo ischemia model has been available to date for routine ischemia research and for faster screening of anti-ischemia drugs. In the present study, we took the opportunity to develop an ex vivo model of partial ischemia using the vascular bed of 4th day incubated chick embryo. Methodology/Principal Findings: Ischemia was created in chick embryo by ligating the right vitelline artery using sterile surgical suture. Hypoxia inducible factor- 1 alpha (HIF-1a), creatine phospho kinase-MB and reactive oxygen species in animal tissues and cells were measured to confirm ischemia in chick embryo. Additionally, ranolazine, N-acetyl cysteine and trimetazidine were administered as an anti-ischemic drug to validate the present model. Results from the present study depicted that blocking blood flow elevates HIF-1a, lipid peroxidation, peroxynitrite level in ischemic vessels while ranolazine administration partially attenuates ischemia driven HIF-1a expression. Endothelial cell incubated on ischemic blood vessels elucidated a higher level of HIF-1a expression with time while ranolazine treatment reduced HIF-1a in ischemic cells. Incubation of caprine heart strip on chick embryo ischemia model depicted an elevated creatine phospho kinase-MB activity under ischemic condition while histology of the treated heart sections evoked edema and disruption of myofibril structures. Conclusions/Significance: The present study concluded that chick embryo partial ischemia model can be used as a novel ex vivo model of ischemia. Therefore, the present model can be used parallel with the known in vivo ischemia models in understanding the mechanistic insight of ischemia development and in evaluating the activity of anti-ischemic drug.status: publishe

Slot: Shortened Loop Internet Transport using Overlay Networks

Overlay routing has emerged as a promising approach to mitigating many problems with Internet routing, such as improving the reliability of Internet paths and supporting multicast communication. As overlay routing is gaining wider acceptance, we argue that it is time t o investigate how overlay networks can benefit Internet transport. This paper presents Slot, a framework that leverages overlay networks to improve the throughput of feedback-based transport protocols. Slot exploits the observation that the throughput of feedback-based transport protocols (e.g., TCP, XCP, VCP, DCCP) is inversely proportional to the length of their end-to-end feedback control loop, and effectively shortens an end-to-end control loop by breaking it up into multiple pipelined shortened sub-loops via intermediaries carefully chosen from an overlay network. As a result, Slot increases the throughput of an end-to-end transport connection to that of the longest sub-loop. This paper studies the potential of Slot and addresses key challenges in the design and the deployment of Slot. The contributions of this paper are three-fold. First, we make the case for Slot by measuring and analyzing the control loop lengths of close to 3.7 million node pairs and their potential benefit from Slot using PlanetLab as an example overlay network. Second, we identify key challenges in the design of Slot and show that a simple, low overhead solution can be used to select an overlay path that can achieve close to the maximum throughput improvement possible. Third, we implement a prototype of Slot and deploy it on PlanetLab to fetch a large set of files crawled from popular web servers. Our results show that compared to directly fetching the same documents, Slot improves the throughput of 95% of the large file transfers, and 50% of these transfers achieve more than 30% increase in throughput

Distributed Hashing for Scalable Multicast in Wireless Ad Hoc Networks

Several multicast protocols for mobile ad hoc networks (MANETs) have been proposed that build multicast trees using location information available from GPS or localization algorithms and use geographic forwarding to forward packets down the multicast trees. These stateless multicast protocols carry encoded membership, location and tree information in each packet. Stateless protocols are more efficient and robust than stateful protocols (ADMR, ODMRP) as they avoid the difficulty of maintaining distributed states in the presence of frequent topology changes in MANETs. However, stateless locationbased multicast protocols are not scalable to large groups because they encode group membership in the header of each data packet, i.e. they incur a per-packet encoding overhead. Additionally, such protocols involve centralized group membership and location management, either at the tree root or the traffic source. In this work, we present the Hierarchical Rendezvous Point Multicast (HRPM) protocol which significantly improves the scalability of stateless location-based multicast with respect to the group size. HRPM incorporates two key design ideas: (1) hierarchical decomposition of multicast groups, and (2) use of distributed geographic hashing to construct and maintain such a hierarchy efficiently. HRPM organizes a large group into a hierarchy of recursively organized manageable-sized subgroups in an effort to reduce per-packet encoding overhead. More importantly, HRPM constructs and maintains this hierarchy at virtually no cost using distributed hashing; distributed hashing is recursively applied at each subgroup for group management and avoids the potentially high cost associated with maintaining distributed state at mobile nodes. The hierarchical organization and the distributed hashing property also allows HRPM to scale to large networks and large numbers of groups. Performance results obtained via detailed simulations demonstrate that HRPM achieves enhanced scalability and performance. Coupled with its leverage of stateless geographic forwarding, HRPM scales well in terms of the group size, the number of groups, the number of sources, as well as the size of the network. In particular, HRPM maintains close to 95% multicast delivery ratio while incurring on average 5.5% per packet tree-encoding overhead for up to 250 group members in a 500-node network. Furthermore, it achieves a steady 95% delivery ratio while incurring nearly constant overhead as the number of groups increases from 2 to 45, while keeping the total number of receivers constant at 180, in a 500-node network. Lastly, it steadily achieves above 90% delivery ratio as the network scales up to 1000 nodes with up to 30% group members. As a reference, we also compared HRPM to ODMRP, a state-of-the-art topology-based multicast protocol that is scalable to large groups. HRPM performs comparably to ODMRP across a wide range of group sizes. More over, HRPM outperforms ODMRP when the network size, the number of groups, or the number of sources increases

Mitigating the Gateway Bottleneck via Transparent Cooperative Caching in Wireless Mesh Networks

Wireless mesh networks (WMNs) have been proposed to provide cheap, easily deployable and robust Internet access. The dominant Internet-bound traffic from clients causes a congestion bottleneck around the gateway, which can significantly limit the throughput of the WMN clients in accessing the Internet. In this paper, we present MeshCache, a transparent caching system for WMNs that exploits the locality in client Internet-bound traffic to mitigate the bottleneck effect at the gateway, thereby improving client perceived performance. MeshCache leverages the fact that a WMN typically spans a small geographic area and hence mesh routers are easily over-provisioned with CPU, memory, and disk storage, and extends the individual wireless mesh routers in a WMN with built-in content caching functionality. It then performs cooperative caching among the wireless mesh routers. We explore two architecture designs for MeshCache: (1) caching at every client access mesh router upon file download, and (2) caching at each mesh router along the route the Internet traffic travels, which requires breaking a single end-to-end transport connection into multiple single-hop transport connections along the route. We also leverage the abundant research results from cooperative web caching in the Internet in designing cache selection protocols for efficiently locating caches containing data objects for these two architectures. We further compare these two MeshCache designs with caching at the gateway router only. Through extensive simulations and evaluations using a prototype implementation on a testbed, we find that MeshCache can significantly improve the performance of client nodes in WMNs. In particular, our experiments with a Squid-based MeshCache implementation deployed on the MAP mesh network testbed with 15 routers show that compared to caching at the gateway only, the MeshCache architecture with hop-by-hop caching reduces the load at the gateway by 38%, improves the average client throughput by 170%, and increases the number of transfers that achieve a throughput greater than 1 Mbps by a factor of 3