A New Feather Mite Species of the Genus \u3ci\u3eTrouessartia\u3c/i\u3e Canestrini (Acariformes: Trouessartiidae) from the Northern Rough-winged Swallow \u3ci\u3eStelgidopteryx serripennis\u3c/i\u3e (Passeriformes: Hirundinidae) in Pennsylvania

A new feather mite species, Trouessartia stelgidopteryx sp. n. (Astigmata: Trouessartiidae), is described from the Northern rough-winged swallow Stelgidopteryx serripennis Newton (Passeriformes: Hirundinidae) in Pennsylvania, USA. The new species is close to the minutipes species group and differs from its representatives and all other known species of the genus Trouessartia in having a unique combination of features in males: the opisthosomal lobes are much longer than wide, they are separated by a large semi-ovate terminal cleft, and their lobar apices bear semi-ovate terminal lamellae with a smooth margin

A Flexible System for Simulating Aeronautical Telecommunication Network

At Old Dominion University, we have built Aeronautical Telecommunication Network (ATN) Simulator with NASA being the fund provider. It provides a means to evaluate the impact of modified router scheduling algorithms on the network efficiency, to perform capacity studies on various network topologies and to monitor and study various aspects of ATN through graphical user interface (GUI). In this paper we describe briefly about the proposed ATN model and our abstraction of this model. Later we describe our simulator architecture highlighting some of the design specifications, scheduling algorithms and user interface. At the end, we have provided the results of performance studies on this simulator

Scalable parallel communications

Coarse-grain parallelism in networking (that is, the use of multiple protocol processors running replicated software sending over several physical channels) can be used to provide gigabit communications for a single application. Since parallel network performance is highly dependent on real issues such as hardware properties (e.g., memory speeds and cache hit rates), operating system overhead (e.g., interrupt handling), and protocol performance (e.g., effect of timeouts), we have performed detailed simulations studies of both a bus-based multiprocessor workstation node (based on the Sun Galaxy MP multiprocessor) and a distributed-memory parallel computer node (based on the Touchstone DELTA) to evaluate the behavior of coarse-grain parallelism. Our results indicate: (1) coarse-grain parallelism can deliver multiple 100 Mbps with currently available hardware platforms and existing networking protocols (such as Transmission Control Protocol/Internet Protocol (TCP/IP) and parallel Fiber Distributed Data Interface (FDDI) rings); (2) scale-up is near linear in n, the number of protocol processors, and channels (for small n and up to a few hundred Mbps); and (3) since these results are based on existing hardware without specialized devices (except perhaps for some simple modifications of the FDDI boards), this is a low cost solution to providing multiple 100 Mbps on current machines. In addition, from both the performance analysis and the properties of these architectures, we conclude: (1) multiple processors providing identical services and the use of space division multiplexing for the physical channels can provide better reliability than monolithic approaches (it also provides graceful degradation and low-cost load balancing); (2) coarse-grain parallelism supports running several transport protocols in parallel to provide different types of service (for example, one TCP handles small messages for many users, other TCP's running in parallel provide high bandwidth service to a single application); and (3) coarse grain parallelism will be able to incorporate many future improvements from related work (e.g., reduced data movement, fast TCP, fine-grain parallelism) also with near linear speed-ups

Marine Leeches of the Eastern United States and the Gulf of Mexico with a Key to the Species

Unlike the Eurasian marine leeches (Johansson, 1896; Selensky, 1915; Herter, 1935; Vasileyev, 1939; Knight-Jones, 1961; Sawyer, 1970; Soós, 1965), those from North America comprise an unusually neglected group, due primarily to the bewildering taxonomy of the members. Most early descriptions were brief, ambiguous, and concerned only with superficial characters. Some of the nominal species reported from the eastern United States and Canada are unrecognizable today, thus perpetuating nomenclatural confusion. We attempt to analyze critically the marine leeches from Newfoundland to Texas, with emphasis on those of the southern states from Virginia to Mississippi. An illustrated dichotomous key and a diagnosis for each species is presented. A synonymy, a list of hosts, the geographical distribution, and biological observations accompany the diagnoses. The poorly known Pacific marine leeches (Moore & Meyer, 1951; Moore, 1952a) will be deferred to another study. We found 14 valid species in the Atlantic Ocean and in the Gulf of Mexico from Newfoundland to Texas. Fortunately, the internal anatomy of most is now well known: Ozobranchus branchiatus (Menzies, 1791); O. margoi (Apathy, 1890); Stibarobdella macrothela (Schmarda, 1861); Branchellion torpedinis Savigny, 1822; Trachelobdella lubrica (Grube, 1840); Oxytonostoma typica Malm, 1863; Branchellion ravenelii (Girard, 1850); Trachelobdella rugosa Moore, 1898; Calliobdella vivida (Verrill, 1872); Platybdella buccalis Nigrelli, 1946; Malmiana nuda Richardson, 1970; Myzobdella lugubris Leidy, 1851; Austrobdella rapax (Verrill, 1873); and a new species provisionally assigned to Malmiana Strand, 1942. The first six are also European or cosmopolitan species. Trachelobdella lubrica, Oxytonostoma typical, and the undescribed species of Malmiana are new to the region under study. Trachelobdella rugosa, Austrobdella rapax, and Platybdella buccalis are reported for the first time since their original descriptions. In addition the following important synonyms are presented for the first time: Calliobdella vivida synonymous with C. carolinensis of Sawyer & Chamberlain (1972) and C. nodulifera of Threlfall (1969); Myzobdella lugubris synonymous with Illinobdella alba, I. elongata, I. richardsoni, and I. moorei of Meyer (1940), Ichthyobdella rapax of Wass (1972) and Cystobranchus virginicus of Paperna and Zwerner (1974); and the undescribed Malmiana species synonymous with Piscicola funduli of Causey (1953). Piscicola zebra Moore, 1898, is species inquirendae

Emerging Marine Diseases: Climate Links and Anthropogenic Factors

Mass mortalities due to disease outbreaks have recently affected major taxa in the oceans. For closely monitored groups like corals and marine mammals, reports of the frequency of epidemics and the number of new diseases have increased recently. A dramatic global increase in the severity of coral bleaching in 1997-98 is coincident with high El Niño temperatures. Such climate-mediated, physiological stresses may compromise host resistance and increase frequency of opportunistic diseases. Where documented, new diseases typically have emerged through host or range shifts of known pathogens. Both climate and human activities may have also accelerated global transport of species, bringing together pathogens and previously unexposed host populations

PAI-1: An Integrator of Cell Signaling and Migration

Cellular migration, over simple surfaces or through complex stromal barriers, requires coordination between detachment/re-adhesion cycles, involving structural components of the extracellular matrix and their surface-binding elements (integrins), and the precise regulation of the pericellular proteolytic microenvironment. It is now apparent that several proteases and protease inhibitors, most notably urokinase plasminogen activator (uPA) and plasminogen activator inhibitor type-1 (PAI-1), also interact with several cell surface receptors transducing intracellular signals that significantly affect both motile and proliferative programs. These events appear distinct from the original function of uPA/PAI-1 as modulators of the plasmin-based proteolytic cascade. The multifaceted interactions of PAI-1 with specific matrix components (i.e., vitronectin), the low-density lipoprotein receptor-related protein-1 (LRP1), and the uPA/uPA receptor complex have dramatic consequences on the migratory phenotype and may underlie the pathophysiologic sequalae of PAI-1 deficiency and overexpression. This paper focuses on the increasingly intricate role of PAI-1 as a major mechanistic determinant of the cellular migratory phenotype

Overexpression of Partner of Numb Induces Asymmetric Distribution of the PI4P 5-Kinase Skittles in Mitotic Sensory Organ Precursor Cells in Drosophila

Unequal segregation of cell fate determinants at mitosis is a conserved mechanism whereby cell fate diversity can be generated during development. In Drosophila, each sensory organ precursor cell (SOP) divides asymmetrically to produce an anterior pIIb and a posterior pIIa cell. The Par6-aPKC complex localizes at the posterior pole of dividing SOPs and directs the actin-dependent localization of the cell fate determinants Numb, Partner of Numb (Pon) and Neuralized at the opposite pole. The plasma membrane lipid phosphatidylinositol (4,5)-bisphosphate (PIP2) regulates the plasma membrane localization and activity of various proteins, including several actin regulators, thereby modulating actin-based processes. Here, we have examined the distribution of PIP2 and of the PIP2-producing kinase Skittles (Sktl) in mitotic SOPs. Our analysis indicates that both Sktl and PIP2 reporters are uniformly distributed in mitotic SOPs. In the course of this study, we have observed that overexpression of full-length Pon or its localization domain (LD) fused to the Red Fluorescent Protein (RFP::PonLD) results in asymmetric distribution of Sktl and PIP2 reporters in dividing SOPs. Our observation that Pon overexpression alters polar protein distribution is relevant because RFP::PonLD is often used as a polarity marker in dividing progenitors

Expression Profiling of a Genetic Animal Model of Depression Reveals Novel Molecular Pathways Underlying Depressive-Like Behaviours

The Flinders model is a validated genetic rat model of depression that exhibits a number of behavioural, neurochemical and pharmacological features consistent with those observed in human depression.In this study we have used genome-wide microarray expression profiling of the hippocampus and prefrontal/frontal cortex of Flinders Depression Sensitive (FSL) and control Flinders Depression Resistant (FRL) lines to understand molecular basis for the differences between the two lines. We profiled two independent cohorts of Flinders animals derived from the same colony six months apart, each cohort statistically powered to allow independent as well as combined analysis. Using this approach, we were able to validate using real-time-PCR a core set of gene expression differences that showed statistical significance in each of the temporally distinct cohorts, representing consistently maintained features of the model. Small but statistically significant increases were confirmed for cholinergic (chrm2, chrna7) and serotonergic receptors (Htr1a, Htr2a) in FSL rats consistent with known neurochemical changes in the model. Much larger gene changes were validated in a number of novel genes as exemplified by TMEM176A, which showed 35-fold enrichment in the cortex and 30-fold enrichment in hippocampus of FRL animals relative to FSL.These data provide significant insights into the molecular differences underlying the Flinders model, and have potential relevance to broader depression research