788 research outputs found

    Detecting Targeted Malicious Email Through Mail Client

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    Sharing and storing of data in the web world is with the help of social networks. Messages are exchanged between hosts using the Simple Mail Transfer Protocol (SMTP). While the email messages are transporting between systems, SMTP communicates delivery parameters using a message envelope separate from the message (header and body) itself. A malicious email message is the one which have been deliberately crafted to cause problems on the server or at the client side. This message may contain a virus. A filtering technique is applied on messaging string contents by applying tokenization and then applying naïve bayesian classifier we classify targeted and non targeted malicious email. A network defender encounters different classes of threat actors with varying intents and capabilities. Conventional computer network attacks exploit network-based listening services such as Web servers. Traditional decision-tree classification algorithms split each node using the best split from all available features. With random forests, each node splits from a randomly selected set of features at that node. It is only focus on mail body not on hyperlinks and attachments. Proposed extension is feature extraction to file attachment metadata. Threat actors might inadvertently leave remnants of infor-mation such as file paths, time zones, or even author names. In addi¬tion, organizations can track features that characterize the types and amounts of email received by a particular email address

    Simian immunodeficiency virus infection in wild-caught chimpanzees from Cameroon

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    Simian immunodeficiency viruses (SIVcpz) infecting chimpanzees (Pan troglodytes) in west central Africa are the closest relatives to all major variants of human immunodeficiency virus type 1 ([HIV-1]; groups M, N and O), and have thus been implicated as the source of the human infections; however, information concerning the prevalence, geographic distribution, and subspecies association of SIVcpz still remains limited. In this study, we tested 71 wild-caught chimpanzees from Cameroon for evidence of SIVcpz infection. Thirty-nine of these were of the central subspecies (Pan troglodytes troglodytes), and 32 were of the Nigerian subspecies (Pan troglodytes vellerosus), as determined by mitochondrial DNA analysis. Serological analysis determined that one P. t. troglodytes ape (CAM13) harbored serum antibodies that cross-reacted strongly with HIV-1 antigens; all other apes were seronegative. To characterize the newly identified virus, 14 partially overlapping viral fragments were amplified from fecal virion RNA and concatenated to yield a complete SIVcpz genome (9,284 bp). Phylogenetic analyses revealed that SIVcpzCAM13 fell well within the radiation of the SIVcpzPtt group of viruses, as part of a clade including all other SIVcpzPtt strains as well as HIV-1 groups M and N. However, SIVcpzCAM13 clustered most closely with SIVcpzGAB1 from Gabon rather than with SIVcpzCAM3 and SIVcpzCAM5 from Cameroon, indicating the existence of divergent SIVcpzPtt lineages within the same geographic region. These data, together with evidence of recombination among ancestral SIVcpzPtt lineages, indicate long-standing endemic infection of central chimpanzees and reaffirm a west central African origin of HIV-1. Whether P. t. vellerosus apes are naturally infected with SIVcpz requires further study

    The birds of the Loyalty Islands (New Caledonia): census, ecological and biogeographical issues

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    The avifauna of the Loyalty Islands comprises 62 species, including 14 breeding or erratic seabirds, 5 migratory birds, 7 herons, ducks and rails, 4 birds of prey, 28 indigenous land breeders (belonging to 33 subspecies) and 2 species introduced from the Grande Terre (main island of New Caledonia). Six species are endemic: 3 on the Grande Terre and in the Loyalty Islands (New Caledonian Friarbird Philemon diemenensis, Green-backed White-eye Zosterops xanthochrous, Striated Starling Aplonis striatus) and 3 only found in the Loyalty Islands (Ouvea Parakeet Eunymphicus uvaeensis, Large Lifou White-eye Zosterops inornatus and Small Lifou White-eye Z. minutus). Eunymphicus is an endemic genus of New Caledonia. Eight subspecies are endemic to both the Grande Terre and the Loyalty Islands and 11 are exclusive of the Loyalty Islands. Of the 24 taxa whose geographical origin could be identified, 58% are identical or similar to those on the Grande Terre, 105 km away, and 42% have affinities with birds in Vanuatu, twice as far away (225 km). The paths of cyclones could explain the specific influence of Vanuatu. The correlation between the islands’land area and the number of species that have successfully settled is very close (r = 0.97) and confirms this biogeographical standard. The land breeding species frequencies vary, with rare localized species limited to some islands (Bluefaced Parrotfinch Erythrura trichroa, Ouvea Parakeet), or possibly extinct (Island Thrush Turdus poliocephalus) and others whose frequency varies widely from place to place (Fan-tailed Cuckoo Cacomantis flabelliformis, Gerygone Gerygone flavolateralis, Silvereye Zosterops lateralis), while others show high (Red-bellied Fruit-Dove Ptilinopus greyii), average (Melanesian Flycatcher Myiagra caledonica, Sacred Kingfischer Todiramphus sanctus) or low (Emerald Dove Chalcophaps indica) frequencies that remain comparable between these islands. The species ecology has been determined with some species associated with wide forests, e.g. the Ouvea Parakeet, while others are typical of the open settings. The threats onto this avifauna are mainly linked to habitat destruction and the impact of introduced species. A specific effort should be made to ensure the protection of populations of that species for which there is the greatest concern, i.e. the Ouvea ParakeetL'avifaune des Loyauté comprend 62 espèces, dont 14 marines nicheuses ou erratiques, 5 migratrices, 7 hérons, canards et râles, 4 rapaces/chouette, 28 oiseaux terrestres nicheurs indigènes (appartenant à 33 sous-espèces) et 2 espèces introduites de Grande Terre. Six espèces sont endémiques à l'archipel néo-calédonien: 3 présentes à la fois en Grande Terre et aux Loyauté: Polochion moine Philemon diemenensis, Zostérops à dos vert Zosterops xanthochrous, Stourne des Loyauté Aplanis striatus et 3 pour les seules Loyauté: Perruche d'Ouvéa Eunymphicus uvaeensis, Zostérops de Lifou Zosterops inornatus et Zostérops minute Z. minutus. Eunymphicus est un genre endémique de Nouvelle-Calédonie. Huit sous-espèces sont endémiques à la fois de Grande Terre et des Loyauté et 11 sont exclusives des Loyauté. Sur 24 taxons dont l'origine géographique peut être établie, 58 % sont identiques ou proches de ceux de Grande Terre distante de 105 km, et 42 % ont des affinités avec des oiseaux du Vanuatu, deux fois plus éloigné (225 km). La trajectoire des cyclones pourrait expliquer cette influence ni-vanuatu particulière. La corrélation entre la surface des îles et le nombre d'espèces qui y ont réussi leur implantation est très étroite (r = 0,97) et vérifie bien cette règle de la biogéographie. La fréquence des espèces terrestres nicheuses est variable, avec des espèces rares et localisées, limitées à certaines îles (Diamant de Kittlitz Erythrura trichroa, Perruche d'Ouvéa) et qui ont peut-être disparu (Merle des Iles Turdus poliocephalus), d'autres dont la fréquence est très inégalement répartie (Coucou à éventail Cacomantis flabelliformis, Gérygone Gerygone flavolateralis, Zostérops à dos noir Zosterops lateralis), d'autres enfin aux fréquences élevées (Ptilope de Grey Ptilinopus greyii), moyennes (Monarque Myiagra caledonica, Martin-chasseur Todiramphus sanctus) ou faibles (Colombine turvert Chalcophaps indica), mais comparables entre les îles. L'écologie des espèces a pu être précisée avec des espèces inféodées aux grandes forêts, parmi lesquelles la Perruche d'Ouvéa, et des espèces typiques des milieux ouverts. Les menaces pesant sur cette avifaune sont essentiellement liées aux destructions d'habitat et à l'impact des espèces introduites. Un effort particulier doit être consenti pour sécuriser les populations de l'espèce dont le statut est le plus préoccupant: la Perruche d'Ouvéa

    FtsK-Dependent Dimer Resolution on Multiple Chromosomes in the Pathogen Vibrio cholerae

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    Unlike most bacteria, Vibrio cholerae harbors two distinct, nonhomologous circular chromosomes (chromosome I and II). Many features of chromosome II are plasmid-like, which raised questions concerning its chromosomal nature. Plasmid replication and segregation are generally not coordinated with the bacterial cell cycle, further calling into question the mechanisms ensuring the synchronous management of chromosome I and II. Maintenance of circular replicons requires the resolution of dimers created by homologous recombination events. In Escherichia coli, chromosome dimers are resolved by the addition of a crossover at a specific site, dif, by two tyrosine recombinases, XerC and XerD. The process is coordinated with cell division through the activity of a DNA translocase, FtsK. Many E. coli plasmids also use XerCD for dimer resolution. However, the process is FtsK-independent. The two chromosomes of the V. cholerae N16961 strain carry divergent dimer resolution sites, dif1 and dif2. Here, we show that V. cholerae FtsK controls the addition of a crossover at dif1 and dif2 by a common pair of Xer recombinases. In addition, we show that specific DNA motifs dictate its orientation of translocation, the distribution of these motifs on chromosome I and chromosome II supporting the idea that FtsK translocation serves to bring together the resolution sites carried by a dimer at the time of cell division. Taken together, these results suggest that the same FtsK-dependent mechanism coordinates dimer resolution with cell division for each of the two V. cholerae chromosomes. Chromosome II dimer resolution thus stands as a bona fide chromosomal process

    Determination of 87Sr/86Sr isotopic ratio in olive oil and pomace using multicollector-ICPMS; analysis of pomace residues as a simpler approach for determination of 87Sr/86Sr ratio in olive oil with low Sr content

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    This study presents an analytical procedure for measuring the 87Sr/86Sr isotopic ratio in olive oil and pomace using multicollector-inductively coupled mass spectrometry (MC-ICPMS). The developed method combines liquid-liquid extraction with an acid solution and degradation of organic residues in the extract by dry ashing and oxidation by H2O2 and HNO3. The method enabled 87Sr/86Sr ratios to be obtained in olive oil with Sr content as low as 0.2 ng/g, with a precision of 54 ppm. The method’s validity was confirmed by an interlaboratory comparison using NIST SRM 2387, providing the first data on its elemental Sr (2380 ± 230 ng/g ; n = 10), and 87Sr/86Sr isotopic composition (0.70908 ± 0.00004 ; n = 14). The procedure was applied to olive oil and pomace samples, showing that they have an identical 87Sr/86Sr ratio, which was consistent with that determined in soils from the same orchards. The results thus revealed that Sr isotopic ratios of olive oil and pomace can both be used in geographical traceability studies of olive oil, which means that, instead of processing large volume of oil, characteristic 87Sr/86Sr signatures of olive oil can be more easily obtained by analyzing small quantities of pomace obtained by centrifuging the oil

    TRANSFAC(®) and its module TRANSCompel(®): transcriptional gene regulation in eukaryotes

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    The TRANSFAC(®) database on transcription factors, their binding sites, nucleotide distribution matrices and regulated genes as well as the complementing database TRANSCompel(®) on composite elements have been further enhanced on various levels. A new web interface with different search options and integrated versions of Match™ and Patch™ provides increased functionality for TRANSFAC(®). The list of databases which are linked to the common GENE table of TRANSFAC(®) and TRANSCompel(®) has been extended by: Ensembl, UniGene, EntrezGene, HumanPSD™ and TRANSPRO™. Standard gene names from HGNC, MGI and RGD, are included for human, mouse and rat genes, respectively. With the help of InterProScan, Pfam, SMART and PROSITE domains are assigned automatically to the protein sequences of the transcription factors. TRANSCompel(®) contains now, in addition to the COMPEL table, a separate table for detailed information on the experimental EVIDENCE on which the composite elements are based. Finally, for TRANSFAC(®), in respect of data growth, in particular the gain of Drosophila transcription factor binding sites (by courtesy of the Drosophila DNase I footprint database) and of Arabidopsis factors (by courtesy of DATF, Database of Arabidopsis Transcription Factors) has to be stressed. The here described public releases, TRANSFAC(®) 7.0 and TRANSCompel(®) 7.0, are accessible under

    Release properties of UCx_x and molten U targets

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    The release properties of UCx_x and molten U thick targets associated with a Nier- Bernas ion source have been studied. Two experimental methods are used to extract the release time. Results are presented and discussed for Kr, Cd, I and Xe

    Guillain-Barre syndrome presenting with sensory disturbance following a herpes virus infection: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>We present a case of an unusual clinical manifestation of Guillain-Barre syndrome following a pre-existing herpes virus infection. Although there have been several reports describing the co-existence of herpes virus infection and Guillain-Barre syndrome, we undertook a more in-depth study of the cross-reactivity between herpes viruses and recommend a follow-up study based on serology tests.</p> <p>Case presentation</p> <p>A 39-year-old healthy Caucasian man with Guillain-Barre syndrome presented to our facility initially with sensory disturbance, followed by an atypical descending pattern of clinical progression. On physical examination, our patient showed hot and cold temperature sensory disturbance under the T4 vertebrae level, symmetrically diminished muscle power mainly to his lower limbs, blurred vision, a loss of taste and paresis and diminished reflexes of his lower limbs. Serology test results for common viruses on hospital admission were positive for cytomegalovirus immunoglobulin M, cytomegalovirus immunoglobulin G, herpes simplex virus immunoglobulin M, herpes simplex virus immunoglobulin G, Epstein-Barr virus immunoglobulin M, and varicella zoster virus immunoglobulin G, borderline for Epstein-Barr virus immunoglobulin G and negative for varicella zoster virus immunoglobulin M. At one month after hospital admission his test results were positive for cytomegalovirus immunoglobulin M, cytomegalovirus immunoglobulin G, herpes simplex virus immunoglobulin G, Epstein-Barr virus immunoglobulin G, varicella zoster virus immunoglobulin G, borderline for herpes simplex virus immunoglobulin M and negative for Epstein-Barr virus immunoglobulin M and varicella zoster virus immunoglobulin M. At his six month follow-up, tests were positive for cytomegalovirus immunoglobulin G, herpes simplex virus immunoglobulin M, herpes simplex virus immunoglobulin G, Epstein-Barr virus immunoglobulin G and varicella zoster virus immunoglobulin G and negative for cytomegalovirus immunoglobulin M, Epstein-Barr virus immunoglobulin M and varicella zoster virus immunoglobulin M.</p> <p>Conclusions</p> <p>The clinical manifestation of Guillain-Barre syndrome in our patient followed a combined herpes virus infection. The cross-reactivity between these human herpes viruses may have a pathogenic as well as evolutionary significance. Our patient showed seroconversion at an early stage of Epstein-Barr virus immunoglobulin M to immunoglobulin G antibodies, suggesting that Epstein-Barr virus might have been the cause of this syndrome. Even if this case is not the first of its kind to be reported, it may contribute to a better understanding of the disease and the cross-reaction mechanisms of herpes virus infections. This case report may have a broader clinical impact across more than one area of medicine, suggesting that cooperation between different specialties is always in the patient's best interest.</p
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