40 research outputs found

    Smart Acknowledgement Distributed Channel Access Scheme for TCP in MANETs

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    TCP upon wireless networks is most challenging issue because of random losses and ACK interference. Also, TCP suffers from performance declination in terms of creating delay and overhead in network because of poor characteristics of wireless channel. In order to overcome these issues, we proposed a Smart Acknowledgement Distributed Channel Access (SADCA) scheme for TCP in MANETs. In the proposed scheme, first a separate Access Category (AC) for data less TCP acknowledgement packets is used and then it is assigned with highest priority. In this way, delay during transmission of packet can be reduced and also packet can be acknowledged immediately. Also, to increase the performance, delay window size can be adjusted by considering the parameters such as transmission rate, number of hops, and channel occupied ratio (COR). Hence the proposed scheme helps to avoid any kind of delay and overhead for sending TCP acknowledgemen

    A SECRET-KEY OF FLEXIBLE CHOICE ON CONFIDENTIAL OUTSIDERS FILES

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    Expansion for data outsourcing may be used becoming an important understanding for a lot of programs. Inside the recent occasions, the efforts that have been made earlier mainly spotlight on minimization of communication needs. Inside the recent cryptography techniques, the essential concern is regarding leveraging of confidentiality of knowledge to deal with cryptographic functions numerous occasions. We produce a study making of understanding key more commanding so it permits knowledge of several cipher-texts, missing of the size increase. We commence an excellent public-key file encryption known to as key-aggregate cryptosystem. Cryptographic techniques of key assignment decreases spending in storing additionally to controlling of secret keys for wide-different cryptographic use. We study a novel cryptosystems of public-key that leave constant size cipher-texts for competent delegation of understanding legal rights for possible cipher-texts. Our strategy is flexible when compared to hierarchical key assignment that saves spaces when the entire key-holders distribute an connected number of legal rights

    DEFINITE OUTLAY OPTIMALITY BY SERVING VOLATILE REQUESTS

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    Several projects were emerged inside the yesteryear couple of years that explore migration of services into cloud platform. More novel programs were created on cloud platform while numerous traditional programs are in addition considering cloud-ward move including programs of content distribution programs. Two important tasks are concerned for just about any go to transfer contents towards cloud storage, also to allocate web service load towards cloud-based web services. Inside our work we design dynamic control formula to place contents and dispatch demands in the hybrid cloud system spanning geo-distributed data centres that reduces general operational expenditure ultimately, prone to the limitations and services information response time

    Slip-Sliding Away: Serial Changes and Homoplasy in Repeat Number in the Drosophila yakuba Homolog of Human Cancer Susceptibility Gene BRCA2

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    Several recent studies have examined the function and evolution of a Drosophila homolog to the human breast cancer susceptibility gene BRCA2, named dmbrca2. We previously identified what appeared to be a recent expansion in the RAD51-binding BRC-repeat array in the ancestor of Drosophila yakuba. In this study, we examine patterns of variation and evolution of the dmbrca2 BRC-repeat array within D. yakuba and its close relatives. We develop a model of how unequal crossing over may have produced the expanded form, but we also observe short repeat forms, typical of other species in the D. melanogaster group, segregating within D. yakuba and D. santomea. These short forms do not appear to be identical-by-descent, suggesting that the history of dmbrca2 in the D. melanogaster subgroup has involved repeat unit contractions resulting in homoplasious forms. We conclude that the evolutionary history of dmbrca2 in D. yakuba and perhaps in other Drosophila species may be more complicated than can be inferred from examination of the published single genome sequences per species

    Late Cretaceous Vicariance in Gondwanan Amphibians

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    Overseas dispersals are often invoked when Southern Hemisphere terrestrial and freshwater organism phylogenies do not fit the sequence or timing of Gondwana fragmentation. We used dispersal-vicariance analyses and molecular timetrees to show that two species-rich frog groups, Microhylidae and Natatanura, display congruent patterns of spatial and temporal diversification among Gondwanan plates in the Late Cretaceous, long after the presumed major tectonic break-up events. Because amphibians are notoriously salt-intolerant, these analogies are best explained by simultaneous vicariance, rather than by oceanic dispersal. Hence our results imply Late Cretaceous connections between most adjacent Gondwanan landmasses, an essential concept for biogeographic and palaeomap reconstructions

    Upregulated IL-1Ξ² in dysferlin-deficient muscle attenuates regeneration by blunting the response to pro-inflammatory macrophages.

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    BACKGROUND: Loss-of-function mutations in the dysferlin gene (DYSF) result in a family of muscle disorders known collectively as the dysferlinopathies. Dysferlin-deficient muscle is characterized by inflammatory foci and macrophage infiltration with subsequent decline in muscle function. Whereas macrophages function to remove necrotic tissue in acute injury, their prevalence in chronic myopathy is thought to inhibit resolution of muscle regeneration. Two major classes of macrophages, classical (M1) and alternative (M2a), play distinct roles during the acute injury process. However, their individual roles in chronic myopathy remain unclear and were explored in this study. METHODS: To test the roles of the two macrophage phenotypes on regeneration in dysferlin-deficient muscle, we developed an in vitro co-culture model of macrophages and muscle cells. We assayed the co-cultures using ELISA and cytokine arrays to identify secreted factors and performed transcriptome analysis of molecular networks induced in the myoblasts. RESULTS: Dysferlin-deficient muscle contained an excess of M1 macrophage markers, compared with WT, and regenerated poorly in response to toxin injury. Co-culturing macrophages with muscle cells showed that M1 macrophages inhibit muscle regeneration whereas M2a macrophages promote it, especially in dysferlin-deficient muscle cells. Examination of soluble factors released in the co-cultures and transcriptome analysis implicated two soluble factors in mediating the effects: IL-1Ξ² and IL-4, which during acute injury are secreted from M1 and M2a macrophages, respectively. To test the roles of these two factors in dysferlin-deficient muscle, myoblasts were treated with IL-4, which improved muscle differentiation, or IL-1Ξ², which inhibited it. Importantly, blockade of IL-1Ξ² signaling significantly improved differentiation of dysferlin-deficient cells. CONCLUSIONS: We propose that the inhibitory effects of M1 macrophages on myogenesis are mediated by IL-1Ξ² signals and suppression of the M1-mediated immune response may improve muscle regeneration in dysferlin deficiency. Our studies identify a potential therapeutic approach to promote muscle regeneration in dystrophic muscle

    Unusually Long Palindromes Are Abundant in Mitochondrial Control Regions of Insects and Nematodes

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    BACKGROUND: Palindromes are known to be involved in a variety of biological processes. In the present investigation we carried out a comprehensive analysis of palindromes in the mitochondrial control regions (CRs) of several animal groups to study their frequency, distribution and architecture to gain insights into the origin of replication of mtDNA. METHODOLOGY/PRINCIPAL FINDINGS: Many species of Arthropoda, Nematoda, Mollusca and Annelida harbor palindromes and inverted repeats (IRs) in their CRs. Lower animals like cnidarians and higher animal groups like chordates are almost devoid of palindromes and IRs. The study revealed that palindrome occurrence is positively correlated with the AT content of CRs, and that IRs are likely to give rise to longer palindromes. CONCLUSIONS/SIGNIFICANCE: The present study attempts to explain possible reasons and gives in silico evidence for absence of palindromes and IRs from CR of vertebrate mtDNA and acquisition and retention of the same in insects. Study of CRs of different animal phyla uncovered unique architecture of this locus, be it high abundance of long palindromes and IRs in CRs of Insecta and Nematoda, or short IRs of 10–20 nucleotides with a spacer region of 12–14 bases in subphylum Chelicerata, or nearly complete of absence of any long palindromes and IRs in Vertebrata, Cnidaria and Echinodermata

    Implementing and compiling clustering using Mac Queens alias K-means apriori algorithm

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    Abstract This paper aims at implementing a Symmetric Multi-Threading. The paper provides a true concurrency, also known as Symmetric Multi-Threading (IACKMA
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