2,508 research outputs found
First Records Of Small Squaregilled Mayflies (ephemeroptera, Caenidae) From The State Of Roraima, Northern Brazil
Conselho Nacional de Desenvolvimento CientÃfico e Tecnológico (CNPq)New records and notes on the distribution of the family Caenidae from Roraima state, Brazil are provided. No previous records were known of this family from Roraima. Our study reports four speciesof Brasilocaenis and Caenis: Brasilocaenis irmleri Puthz, 1975, Caenis chamie Alba-Tercedor & Mosquera, 1999, C. fittkaui Malzacher, 1986 and C. reissi Malzacher, 1986. In addition, an unidentified species of Latineosus, based in a unique exuvia, was also found. © 2016 Check List and Authors.124407623/2013–2, CNPq, Conselho Nacional de Desenvolvimento CientÃfico e TecnológicoConselho Nacional de Desenvolvimento CientÃfico e Tecnológico (CNPq
Pd-catalyzed allylative dearomatisation using Grignard reagents
Pd-catalyzed allylative dearomatisation of naphthyl halides is shown to be feasible by employing Grignard reagents. The high reactivity of the nucleophile allows for fast reactions and low catalyst loading, while a plethora of successfully substituted compounds illustrate the broad scope. Five membered heteroaromatic compounds are also demonstrated to be reactive under similar conditions.</p
Evaluation of SCION for User-driven Path Control:a Usability Study
The UPIN (User-driven Path verification and control in Inter-domain Networks) project aims to implement a way for users of a network to control how their data is traversing it. In this paper we investigate the possibilities and limitations of SCION for user-driven path control. Exploring several aspects of the performance of a SCION network allows us to define the most efficient path to assign to a user, following specific requests. We extensively analyze multiple paths, specifically focusing on latency, bandwidth and data loss, in SCIONLab, an experimental testbed and implementation of a SCION network. We gather data on these paths and store it in a database, that we then query to select the best path to give to a user to reach a destination, following their request on performance or devices to exclude for geographical or sovereignty reasons. Results indicate our software is a viable option to offer users many paths to choose from, following a series of requests, and therefore perform user-driven path control in a SCION network.</p
Increasing the Transparency, Accountability and Controllability of multi-domain networks with the UPIN framework
Demands for a more trustworthy Internet are constantly increasing, in particular to support emerging critical services such as intelligent urban transport systems and smart energy grids. Such cyber-physical systems require more insight into the properties of network operators (e.g., in terms of the security posture of their equipment) and more control over which network operators transport their data, thus going well beyond the traditional security paradigm which the Internet security community currently focuses on (confidentiality, availability, and integrity). In this work-in-progress paper we propose the UPIN framework, which aims to fulfill these new trust requirements. The framework advances the state-of-the-art by defining components needed to incorporate transparency, accountability, and controllability into the Internet or other types of inter-domain networks. The framework is based on our analysis of a smart grid use case to understand the specific needs of critical service providers and a literature study on existing technologies. We also discuss our ongoing work, and the demands and challenges of implementing and deploying the UPIN framework
Increasing the Transparency, Accountability and Controllability of multi-domain networks with the UPIN framework
Electrophilic Trapping of Semibenzenes
[Image: see text] In this work, we demonstrate how allylative dearomatization of benzyl chlorides can provide direct access to a variety of semibenzenes. These scaffolds behave as highly reactive nucleophiles in the presence of carbocations. In addition, semibenzenes are susceptible to intramolecular rearrangements rendering a broad scope of functionalized arenes. An analysis of this new reactivity is reported, as well as the rationale behind the observed intramolecular reorganizations
Meiotic behavior of a nonaploid accession endorses x = 6 for Brachiaria humidicola (Poaceae).
Brachiaria humidicola (Poaceae), originally from Africa, is an economically important pasture plant in tropical South America. An accession of B. humidicola (H038) collected from the wild African savanna (Mbeya, Tanzania) showed irregular microsporogenesis. This meiotic behavior was consistent with an allopolyploid origin. Multivalent chromosome association at diakinesis gave tri- to octavalents, associated with two nucleoli in some cells. Six non-congregated univalents in metaphase I and anaphase I, along with previous lines of evidence for x = 6 in B. humidicola, confirm H038 as a nonaploid accession, 2n = 9x = 54. Asynchrony in the genome during microsporogenesis also corroborated this assumption. Its putative origin could be a cross between two related species with different rhythms in meiosis. The meiotic behavior of this accession reinforces the hypothesis of the existence of a new basic chromosome number (x = 6) for Brachiaria. The use of this accession in the breeding of this important forage grass for the tropics is discussed
Compensatory Feto-Placental Upregulation of the Nitric Oxide System during Fetal Growth Restriction
Background: Fetal Growth Restriction is often associated with a feto-placental vascular dysfunction conceivably involving endothelial cells. Our study aimed to verify this pathogenic role for feto-placental endothelial cells and, coincidentally, demonstrate any abnormality in the nitric oxide system. Methods: Prenatal assessment of feto-placental vascular function was combined with measurement of nitric oxide (in the form of S-nitrosohemoglobin) and its nitrite byproduct, and of the endogenous nitric oxide synthase inhibitor asymmetric dimethylarginine. Umbilical vein endothelial cells were also harvested to determine their gene profile. The study comprised term pregnancies with normal (n = 40) or small-for-gestational-age (n = 20) newborns, small-for-gestational-age preterm pregnancies (n = 15), and bi-chorial, bi-amniotic twin pregnancies with discordant fetal growth (n = 12). Results: Umbilical blood nitrite (p<0.001) and S-nitrosohemoglobin (p = 0.02) rose with fetal growth restriction while asymmetric dimethylarginine decreased (p = 0.003). Nitrite rise coincided with an abnormal Doppler profile from umbilical arteries. Fetal growth restriction umbilical vein endothelial cells produced more nitrite and also exhibited reciprocal changes in vasodilator (upwards) and vasoconstrictor (downwards) transcripts. Elevation in blood nitrite and S-nitrosohemoglobin persisted postnatally in the fetal growth restriction offspring. Conclusion: Fetal growth restriction is typified by increased nitric oxide production during pregnancy and after birth. This response is viewed as an adaptative event to sustain placental blood flow. However, its occurrence may modify the endothelial phenotype and may ultimately represent an element of risk for cardiovascular disease in adult life.Fil: Pisaneschi, Silvia. Università degli Studi di Pisa; Italia. Scuola Superiore Sant’Anna; ItaliaFil: Strigini, Francesca A. L.. Università degli Studi di Pisa; ItaliaFil: Sanchez, Angel Matias. Università degli Studi di Pisa; Italia. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Mendoza. Instituto de Medicina y BiologÃa Experimental de Cuyo; ArgentinaFil: Begliuomini, Silvia. Università degli Studi di Pisa; ItaliaFil: Casarosa, Elena. Università degli Studi di Pisa; ItaliaFil: Ripoli, Andrea. National Research Council. Institute of Clinical Physiology, ; ItaliaFil: Ghirri, Paolo. Università degli Studi di Pisa; ItaliaFil: Boldrini, Antonio. Università degli Studi di Pisa; ItaliaFil: Fink, Bruno. Noxygen Science Transfer and Diagnostics; AlemaniaFil: Genazzani, Andrea R.. Università degli Studi di Pisa; ItaliaFil: Coceani, Flavio. Scuola Superiore Sant’Anna; ItaliaFil: Simoncini, Tommaso. Università degli Studi di Pisa; Itali
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