DNA Barcoding and Morphological Identification of Benthic Nematodes Assemblages of Estuarine Intertidal Sediments: Advances in Molecular Tools for Biodiversity Assessment

Concerns regarding the status of marine ecosystems have increased in part due to traditional and emerging human activities in marine waters, driving a demand for approaches with high sample throughput capability to improve ecosystem monitoring. Nematodes are already used as indicator species in biodiversity assessments and biomonitoring of terrestrial and marine systems, with molecular approaches offering the opportunity to utilize these organisms further in large scale ecological surveys and environmental assessments. Based on an available nematode dataset for estuarine sediments of the Mira estuary (SW coast, Portugal), we evaluated the diversity of the nematode community of this system, using the molecular markers 18S rRNA and COI genes. These approaches were compared to voucher specimens from a morphological characterization of the same samples allowing validation and comparison between nematode communities. The spatial and temporal variability of the density and diversity of the nematode assemblages was analyzed based on morphological characterization to allow the validation and efficiency of the genetic characterization. A PCO ordination plot showed a distinct separation of the assemblages between sampling occasions confirmed by PERMANOVA analysis, which showed significant differences, although no significant differences were detected between sampling sites. The morphological characterization identified 50 genera of which only 26 and 25 distinct 18S rRNA and COI DNA barcodes, respectively, were obtained. 90.2% of the morphologically identified specimens representing eleven different genera, successfully generated DNA barcodes for both 18S rRNA and COI genes. This study confirmed that the success of the 18S rRNA gene PCR amplification is higher than of COI gene with 43 species amplified against 34. The study highlights a limitation of available sequences for both targets in databases when compared to the known diversity of marine nematodes. The gene sequences of this study enriched the databases, contributing gene sequences from 7 to 16 new genera for the 18S rRNA and COI genes, respectively. A robust database of gene sequences is a prerequisite for the development of robust high sample throughput techniques to be applied in marine assessing and monitoring programs

Synthesis, structure, solution behaviour and biological evaluation of oxidovanadium(IV/V) complexes: Substrate specific DMSO assisted methylation of a thiosemicarbazone

The synthesis and characterization of an oxidovanadium(IV) [VIVO(L)(acac)] (1) and of two dioxidovanadium(V) [VVO2(L')] (2) and [VVO2(L)] (2a) complexes of the Schiff base formed from the reaction of 4-(p-fluorophenyl) thiosemicarbazone with pyridine-2-aldehyde (HL) is described.The oxidovanadium(IV) species [VIVO(L)(acac)] (1) was synthesized by the reaction of VIVO(acac)2 with the thiosemicarbazone HL in refluxing ethanol. The recrystallization of [VIVO(L)(acac)] (1) in DMF, CH3CN or EtOH gave the same product i.e. the dioxidovanadium(V) complex [VVO2(L)] (2a); however, upon recrystallization of 1 in DMSO a distinct compound [VVO2(L')] (2) was formed, wherein the original ligand L- is transformed to a rearranged one, L’-. In the presence of DMSO the ligand in complex 1 is found to undergo methylation at the carbon centre attached to imine nitrogen (aldimine) and transformed to the corresponding V VO2- species through in situ reaction. The synthesized HL and the metal 2 complexes were characterized by elemental analysis, IR, UV–Vis, NMR and EPR spectroscopy. The molecular structure of [VVO2(L')] (2) was determined by single crystal X–ray crystallography.The methylation of various other ligands and complexes prepared from different vanadium precursors under similar reaction conditions was also attempted and it was confirmed that the imine methylation observed is both ligand and metal precursor specific. Complexes 1 and 2 show in vitro insulin-like activity against insulin responsive L6 myoblast cells, with complex 1 being more potent. In addition, the in vitro cytotoxicity studies of HL, and of complexes 1 and 2 against the MCF–7 and Vero cell lines were also done. The ligand is not cytotoxic and complex 2 is significantly more cytotoxic than 1. DAPI staining experiments indicate that increase in time of incubation as well as increase of concentration of the complexes lead to increase in cell death

Conserving pattern and process in the Southern Ocean: designing a Marine Protected Area for the Prince Edward Islands

South Africa is currently proclaiming a Marine Protected Area (MPA) in the Exclusive Economic Zone (EEZ) of its sub-Antarctic Prince Edward Islands. The objectives of the MPA are to: 1) contribute to a national and global representative system of MPAs, 2) serve as a scientific reference point to inform future management, 3) contribute to the recovery of the Patagonian toothfish (Dissostichus eleginoides), and 4) reduce the bird bycatch of the toothfish fishery, particularly of albatrosses and petrels. This study employs systematic conservation planning methods to delineate a MPA within the EEZ that will conserve biodiversity patterns and processes within sensible management boundaries, while minimizing conflict with the legal toothfish fishery. After collating all available distributional data on species, benthic habitats and ecosystem processes, we used C-Plan software to delineate a MPA with three management zones: four IUCN Category Ia reserves (13% of EEZ); two Conservation Zones (21% of EEZ); and three Category IV reserves (remainder of EEZ). Compromises between conservation target achievement and the area required by the MPA are apparent in the final reserve design. The proposed MPA boundaries are expected to change over time as new data become available and as impacts of climate change become more evident

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Membrane structure and interactions of a short Lycotoxin I anaiogue

Lycotoxin I and Lycotoxin II are natural anti-microbial peptides, that were identified in the venom of the Wolf Spider Lycosa carolinensis. These peptides were found to be potent growth inhibitors for bacteria (Escherichia coli) and yeast (Candida glabrata) at micromolar concentrations. Recently, shortened analogues of Lycol and LycoII have been reported to have decreased haemolytic effects. A shorter Lyco-I analogue studied, Lycol 1-15 (H-IWLTALKFLGKHAAK-NH2), was active only above 10 pm, but was also the least haemolytic. On the basis of these findings, we became interested in obtaining a deeper insight into the membrane activity of LycoI 1-15, as this peptide may represent the first major step for the future development of selective, i.e. non-haemolytic, Lycotoxin-based antibiotics. The interaction of this peptide with liposomes of different composition was studied by microcalorimetry [differential scanning calorimetry (DSC) and isothermal titration calorimetry (ITC)l and CD. The results obtained from the calorimetric and spectroscopic techniques were jointly discussed in an attempt to further understand the interaction of this peptide with model membranes. Copyright (c) 2007 European Peptide Society and John Wiley & Sons, Ltd

Geology of the Nevado Coropuna volcanic complex

The Nevado Coropuna volcanic complex (NCVC), located in the northernmost CAVZ (15°3’ S, 72º39’ W), includes several edifices, aligned WNW-ESE above Neogene ignimbrites. Adjacent composite volcanoes include the Late Pliocene, eroded Sunjillpa to the WNW and the glacially eroded, 0.6-0.25 Ma-old Cunciacha to the ESE. Located on the west flank of the Western Cordillera, the asymmetric volcanic complex shows stubby lava flows overlying the NE, 4500 m-high plateau, contrasting with long, inverted lava flows and debris-avalanche deposits filling deep valleys draining the steep SW flanks. The central, highest NCVC is a cluster of five, aligned lava domes reaching 6160 and 6330 masl. The dome cluster and its voluminous lava flows overlie an old stratovolcano with inverted lava flows dated at 1.02 Ma. The 0.4 Ma-old base of dome cluster is overlain by lower lava flows c. 270 - 254 ka, middle lava flows c. 118 - 108 ka, and the uppermost lava domes 70 – 60 ka. A high-spatial resolution DEM shows six vents on the domes and one collapse scar open to the south. NCVC has grown atop a caldera as shown by AMS data collected on Early Quaternary ignimbrites dipping away west, south and east of NCVC, and by abnormal contacts with both adjacent volcanoes to the WNW and the ESE. All lavas show two major compositional fields of high-K andesites and dacites (SiO2 57-67%wt). Harker diagrams and trace elements suggest AFC magmatic processes. Although CNVC tephra and PDC deposits represent a small volume, we observed Late Glacial Plinian fallout are scattered and Holocene ashfall layers are associated with three lava flows, the youngest being 1700 to 2400 yr old. The Nevado Coropuna ice cap c. 44.1 km2 is arguably the largest in the world tropical belt

AnBx - Security Protocols Design and Verification

Designing distributed protocols is challenging, as it requires actions at very different levels: from the choice of network-level mechanisms to protect the exchange of sensitive data, to the definition of structured interaction patterns to convey application-specific guarantees. Current security infrastructures provide very limited support for the specification of such guarantees. As a consequence, the high-level security properties of a protocol typically must often be hard-coded explicitly, in terms of low-level cryptographic notions and devices which clutter the design and undermine its scalability and robustness. To counter these problems, we propose an extended Alice & Bob notation for protocol narrations (AnBx) to be employed for a purely declarative modelling of distributed protocols. These abstractions provide a compact specification of the high-level security guarantees they convey, and help shield the design from the details of the underlying cryptographic infrastructure. We discuss an implementation of the abstractions based on a translation from the AnBx notation to the AnB language supported by the OFMC [1,2] verification tool. We show the practical effectiveness of our approach by revisiting the iKP e-payment protocols, and showing that the security goals achieved by our declarative specification outperform those offered by the original protocols

Loss of Kat2A Enhances Transcriptional Noise and Depletes Acute Myeloid Leukemia Stem-Like Cells

Acute Myeloid Leukemia (AML) is an aggressive hematological malignancy with abnormal progenitor self-renewal and defective myelo-monocytic differentiation. Its pathogenesis comprises subversion of transcriptional regulation, through mutation and by hijacking normal chromatin regulation. Kat2a is a histone acetyltransferase central to promoter activity that we recently associated with stability of pluripotency networks, and identified as a genetic vulnerability in AML. Through combined chromatin profiling and single-cell transcriptomics, we demonstrate that Kat2a contributes to leukemia propagation through homogeneity of transcriptional programs and preservation of leukemia stem-like cells. Kat2a loss reduces transcriptional bursting frequency in a subset of gene promoters, generating enhanced variability of transcript levels but minimal effects on mean gene expression. Destabilization of target programs shifts cellular equilibrium out of self-renewal towards differentiation. We propose that control of transcriptional variability is central to leukemia stem-like cell propagation, and establish a paradigm exploitable in different tumors and at distinct stages of cancer evolution.This work was funded by a Kay Kendall Leukaemia Fund Intermediate Fellowship (KKL888) and by a Leuka John Goldman Fellowship for Future Science (2017) to C.P.. S.P. is funded through a Cambridge-DBT Lectureship; R.K. was funded by an Isaac Newton Trust (INT) Research Grant and a Wellcome Trust ISSF/INT/University of Cambridge Joint Research Grant to C.P.; S.G. is funded by a Lady Tata Memorial Trust PhD Studentship, a Trinity Henry Barlow Trust Scholarship, and the Cambridge Trust; K.Z. received funding from AIRC (Italian Association for Cancer Research) and is the current recipient of a European Commission Horizon 2020 Marie Sklodowska Curie Post-Doctoral Fellowship

Modeling Monetary Policy

We develop a macroeconomic framework where money issupplied against only few eligible securities in open marketoperations. The relationship between the policy rate,expected inflation and consumption growth is affected bymoney market conditions, i.e. the varying liquidity value ofeligible assets and the associated risk. This induces a liquiditypremium, which explains the observed systematic wedgebetween the policy rate and consumption Euler interest ratethat standard models equate. It further implies a dampenedresponse of consumption to policy rate shocks that is humpshapedwhen we account for realistic central bank transfersand the dynamics of bond holdings

Estudio geológico preliminar del complejo volcánico nevado Coropuna

El Complejo Volcánico Nevado Coropuna (CVNC) está ubicado en el extremo norte de la Zona Volcánica de los Andes Centrales (15 ° 3 ‘S, 72º39 ‘O), incluye varios edificios alineados en dirección ONO-ESE y emplazados sobre ignimbritas del Neogeno (13-2 Ma). Adyacente al CVNC se tienen dos volcanes, el estratovolcán Sunjillpa del Plioceno tardío en su extremo occidental, y el estratovolcán Cuncaicha de hace 0,6 -0,25 Ma, en su extremo oriental. El CVNC es típicamente asimétrico, está en el borde de la Cordillera Occidental y está conformado principalmente por flujos de lava, domos, domo « cluster » y domo-coladas. Los flujos de lava de corto recorrido, normalmente de menos de 7 km, cubren la meseta NE, N y NO, pero flujos de lava de mayor recorrido, entre 10 y 16 km, se han emplazados en los valles profundos ubicados al sur. También en la zona sur se han dentificado importantes depósitos de avalanchas de escombros, rellenando valles profundos a más de 20 km de distancia. En la parte central y más alta del CVNC se han identifi cado al menos 05 “clusters” de domos, de este a oeste, son el Yanaranra (6305 msnm), Coropuna (6160 msnm), Paiche (6330 msnm), Casulla (6377 msnm) y Escalera (6171 msnm). Recientes dataciones obtenidas en el marco de este proyecto arrojaron edades alrededor de 0.4 Ma para lavas ubicadas en la base, las cuales están cubiertas por lavas con edades entre 270-254 ka. En la parte media se han datado lavas entre 118-108 ka, y en la parte superior de los “clusters” de domos se han obtenido edades entre 70 - 60 ka. En base a un modelo de elevación digital (DEM) de 3 m de resolución, se han identifi cado al menos 6 centro de emisión, 5 domos « cluster », una escarpa de colapso principal abierta en dirección sur. Las lavas son andesitas y dacitas, con concentraciones de SiO2 que varían entre 57 a 67 % wt. Todas presentan alto contenido de K. Los diagramas de Harker sugieren un importante proceso de diferenciación magmática, así como procesos de AFC