Progress report on identification of "organisms" in Lake Victoria responsible for echosounder traces

Exploratory fishing with midwater trawls in the pelagic zone of Lake Victoria generally yielded low quantities of fish even where dense traces appeared on the echosounder. Efforts to identify the "organisms" met with limited success. Types of gear were tested the midwater trawl, high-speed beam trawl, Lampara net, zooplankton net and SCUBA. This information plus that of earlier investigators indicate that the bulk of the traces are not caused by fish. The evidence however is not conclusive and further studies are warranted. Some recommendations for study are presented

CHOLANE AND LANOSTANE DERIVATIVES: ANTIMICROBIAL EVALUATION

Steroids are natural compounds with several important applications in many fields of research, such as medicinal chemistry, pharmacology, supramolecular chemistry and nanotechnology.In particular, bile acids such as lithocholic acid (LCA) and ursodeoxycholic acid (UDCA) have been considered quite useful as starting points for a rich and different set of medicinal chemistry activities. Besides, the discovery of bioactive ingredients from plants and fungi is always the main target in medicinal chemistry. The lanostane-type triterpenoid 3b-hydroxylanosta-8,24-diene-21-oic acid (Trametenolic acid, TMA) was the main bioactive component of Gloeophyllum odoratum, which was reported to possess widely bioactivities, including tumor cell anti-proliferation effects (for example, human HL-60 leukemia, human KB epidermoid carcinoma, murine L1210 leukemia cells, Caski, HT-3, T-24, etc.), inhibition of enzyme activity (human thrombin, bovine trypsin and so on).Nevertheless, trametenolic acid was scarcely investigated as antimicrobial agent. Structurally, bile acids (LCA and UDCA) and trametenolic acid are similar since they may be regarded as consisting of two components, a rigid steroid nucleus and an aliphatic side chain possessing a carboxyl group. On the basis of these considerations, six new compounds bearing a guanidine moiety in their side chain were synthesized using LCA, UDCA and TMA as starting materials. The parent bile acids, TMA and their resulting derivatives were evaluated for antimicrobial activity against S. aureus, B. subtilis and M. smegmatis. The derivative 3a-hydroxy-23-guanidino-5b-cholane showed the best activity, with MIC values of 12.5 \u3bcM against S. aureus, 5 \u3bcM against B. subtilis and 50 \u3bcM against M. smegmatis. The cytotoxic activity of bile acids, trametenolic acid and derivatives was also evaluated against HT-29 cell lin

Altered inflammasome machinery as a key player in the perpetuation of Rett syndrome oxinflammation

Rett syndrome (RTT) is a progressive neurodevelopmental disorder mainly caused by mutations in the X-linked MECP2 gene. RTT patients show multisystem disturbances associated with an oxinflammatory status. Inflammasomes are multi-protein complexes, responsible for host immune responses against pathogen infections and redox-related cellular stress. Assembly of NLRP3/ASC inflammasome triggers pro-caspase-1 activation, thus, resulting in IL-1β and IL-18 maturation. However, an aberrant activation of inflammasome system has been implicated in several human diseases. Our aim was to investigate the possible role of inflammasome in the chronic subclinical inflammatory condition typical of RTT, by analyzing this complex in basal and lipopolysaccharide (LPS)+ATP-stimulated primary fibroblasts, as well as in serum from RTT patients and healthy volunteers. RTT cells showed increased levels of nuclear p65 and ASC proteins, pro-IL-1β mRNA, and NLRP3/ASC interaction in basal condition, without any further response upon the LPS + ATP stimuli. Moreover, augmented levels of circulating ASC and IL-18 proteins were found in serum of RTT patients, which are likely able to amplify the inflammatory response. Taken together, our findings suggest that RTT patients exhibited a challenged inflammasome machinery at cellular and systemic level, which may contribute to the subclinical inflammatory state feedback observed in this pathology

The Spectrum of Integrated Millimeter Flux of the Magellanic Clouds and 30-Doradus from TopHat and DIRBE Data

We present measurements of the integrated flux relative to the local background of the Large and Small Magellanic Clouds and the region 30-Doradus (the Tarantula Nebula) in the LMC in four frequency bands centered at 245, 400, 460, and 630 GHz, based on observations made with the TopHat telescope. We combine these observations with the corresponding measurements for the DIRBE bands 8, 9, and 10 to cover the frequency range 245 - 3000 GHz (100 - 1220 micrometers) for these objects. We present spectra for all three objects and fit these spectra to a single-component greybody emission model and report best-fit dust temperatures, optical depths, and emissivity power-law indices, and we compare these results with other measurements in these regions and elsewhere. Using published dust grain opacities, we estimate the mass of the measured dust component in the three regions.Comment: 41 pages, 4 figures. Accepted for publication in Astrophysical Journa

Uniform partition of graphs: Complexity results, algorithms and formulations

In this presentation, we address centered and non centered equipartition problems on graphs into p connected components (p-partitions). In the former case, each class of the partition must contain exactly one special vertex called center, whereas in the latter, partitions are not required to fulfil this condition. Among the different equipartition problems considered in the literature, we focus on: 1) Most Uniform Partition (MUP) and 2) Uniform Partition (UP). Both criteria are defined either w.r.t. weights assigned to each vertex or to costs assigned to each vertex-center pair. Costs are assumed to be flat, i.e., they are independent of the topology of the graph. With respect to costs, MUP minimizes the difference between the maximum and minimum cost of the components of a partition and UP refers to optimal min-max or max-min partitions. Additionally, we present various problems of partitioning a vertex-weighted undirected graph into p connected components minimizing the gap that is a measure related to the difference between the largest and the smallest vertex weight in the component of the partition. For all the problems considered here, we provide polynomial time algorithms, as well as, NP-complete results even on very special classes of graphs like trees. For the centered partitioning problems, we also present a new mathematical programming formulation that can be compared with the ones already provided in the literature for similar problems

Water Quality Monitoring: A comparative case study of municipal and Curtin Sarawak’s lake samples

In this study, particle size distribution and zeta potential of the suspended particles in municipal water and lake surface water of Curtin Sarawak's lake were compared and the samples were analysed using dynamic light scattering method. High concentration of suspended particles affects the water quality as well as suppresses the aquatic photosynthetic systems. A new approach has been carried out in the current work to determine the particle size distribution and zeta potential of the suspended particles present in the water samples. The results for the lake samples showed that the particle size ranges from 180nm to 1345nm and the zeta potential values ranges from -8.58 mV to -26.1 mV. High zeta potential value was observed in the surface water samples of Curtin Sarawak's lake compared to the municipal water. The zeta potential values represent that the suspended particles are stable and chances of agglomeration is lower in lake water samples. Moreover, the effects of physico-chemical parameters on zeta potential of the water samples were also discussed

Subsurface life can modify volatile cycling on a planetary scale

The past decade of environmental microbiology has revealed that subsurface environments, both marine and continental, harbor one of the largest ecosystems of our planet, with diversity and biomass rivaling those of the surface. In addition, subsurface life has been recently shown to contribute significantly to the planet’s biogeochemistry, with microbial activity potentially playing an important role in controlling the flux and composition of volatiles recycled between the Earth’s surface and interior, which has broad implications for the search for life beyond our planet. Current efforts to discover extraterrestrial life are focused on planetary bodies with largely inhospitable surfaces, such as Mars, Venus, Europa, Titan, and Enceladus. In these locations, subsurface environments might provide niches of habitability, making the study of deep microbial life a priority for future astrobiological missions. Understanding how volatile elements are exchanged between planetary surfaces and interiors and the role of a subsurface biosphere in altering their composition and flux might provide a tractable target for defining planetary habitability and the detection of subsurface life forms.Fil: Giovanelli, D.. Università degli Studi di Napoli Federico II; Italia. Tokyo Institute of Technology; Japón. Rutgers University; Estados Unidos. Consiglio Nazionale delle Ricerche; Italia. Woods Hole Oceanographic Institution; Estados UnidosFil: Barry, P. H.. Woods Hole Oceanographic Institution; Estados UnidosFil: Bekaert, D. V.. Woods Hole Oceanographic Institution; Estados UnidosFil: Chiodi, Agostina Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; ArgentinaFil: Cordone, A.. Università degli Studi di Napoli Federico II; ItaliaFil: Covone, G.. Università degli Studi di Napoli Federico II; Italia. Istituto Nazionale di Astrofisica; Italia. Istituto Nazionale di Fisica Nucleare; ItaliaFil: Jessen, G.. Universidad Austral de Chile; ChileFil: Lloyd, K.. University of Tennessee; Estados UnidosFil: de Moor, J. M.. Universidad Nacional; Costa RicaFil: Morrison, S. M.. Carnegie Institution For Science; Estados UnidosFil: Schrenk, M. O.. Michigan State University; Estados UnidosFil: Vitale Brovarone, A.. Alma Mater Studiorum Universit`a Di Bologna; Italia. Sorbonne University; Francia. Museum National d’Histoire Naturelle; Franci

Endothelial cells from umbilical cord of women affected by gestational diabetes: A suitable in vitro model to study mechanisms of early vascular senescence in diabetes

Human umbilical cord endothelial cells (HUVECs) obtained from women affected by gestational diabetes (GD-HUVECs) display durable pro-atherogenic modifications and might be considered a valid in vitro model for studying chronic hyperglycemia effects on early endothelial senescence. Here, we demonstrated that GD- compared to C-HUVECs (controls) exhibited oxidative stress, altered both mitochondrial membrane potential and antioxidant response, significant increase of senescent cells characterized by a reduced NAD-dependent deacetylase sirtuin-1 (SIRT1) activity together with an increase in cyclin-dependent kinase inhibitor-2A (P16), cyclin-dependent kinase inhibitor-1 (P21), and tumor protein p53 (P53) acetylation. This was associated with the p300 activation, and its silencing significantly reduced the GD-HUVECs increased protein levels of P300 and Ac-P53 thus indicating a persistent endothelial senescence via SIRT1/P300/P53/P21 pathway. Overall, our data suggest that GD-HUVECs can represent an “endothelial hyperglycemic memory” model to investigate in vitro the early endothelium senescence in cells chronically exposed to hyperglycemia in vivo

Outstanding Survival and Regeneration Process by the Use of Intelligent Acellular Dermal Matrices and Mesenchymal Stem Cells in a Burn Pig Model

A pig model with a deep large burn was used to study the regeneration process induced by mesenchymal stem cells (MSCs) and acellular pig dermal matrices, made intelligent by the combination with biodegradable nanofibers loaded with growth factors (granulocitemacrophage colony-stimulating factor and epidermal growth factor) and coated with the anti-CD44 monoclonal antibody (intelligent acellular dermal matrices, IADMs). These IADMs are specially designed to integrate in the wound bed as new biological scaffolds as well as to specifically recruit and attach circulating and/or externally applied MSCs through the anti-CD44 antibody while delivering precise amounts of growth factors. In this way, the reparative process as well as the aesthetic and functional results were enhanced in our burn model. The animal survived, the wound was completely closed, and total regeneration of the skin was obtained without much scarring. Surprisingly, hair follicles and other skin appendages developed despite the severity and deepness of the burn. Even burned muscles and ribs seemed to have undergone a regenerative process by the end of the study. Based on these findings, we have proposed the use of IADMs and autologous, allogeneic or xenogeneic MSCs, as a new paradigm for the future treatment of large burns and probably other dermatological and cosmetic human conditions.Facultad de Ciencias Médica

Speeding-Up Expensive Evaluations in High-Level Synthesis Using Solution Modeling and Fitness Inheritance

High-Level Synthesis (HLS) is the process of developing digital circuits from behavioral specifications. It involves three interdependent and NP-complete optimization problems: (i) the operation scheduling, (ii) the resource allocation, and (iii) the controller synthesis. Evolutionary Algorithms have been already effectively applied to HLS to find good solution in presence of conflicting design objectives. In this paper, we present an evolutionary approach to HLS that extends previous works in three respects: (i) we exploit the NSGA-II, a multi-objective genetic algorithm, to fully automate the design space exploration without the need of any human intervention, (ii) we replace the expensive evaluation process of candidate solutions with a quite accurate regression model, and (iii) we reduce the number of evaluations with a fitness inheritance scheme. We tested our approach on several benchmark problems. Our results suggest that all the enhancements introduced improve the overall performance of the evolutionary search