440 research outputs found

    Implementation of a sensorized neonatal head model for gynechological training

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    During labor it is very important to know the exact position and orientation of the fetal head when descending the birth canal. Indeed, incorrect evaluations may lead to dangerous situations for both the infant and the mother. Usually, gynecologists and midwives rely on their experience to determine the head position and to evaluate the risk level of each delivery. In this context, it is essential to train new physicians and midwives to correctly manage different types of delivery. Here, we present the design and implementation of a realistic sensorized neonatal head that could be used on low-cost birth simulators for training and evaluation of residents and midwifery students

    CHOLANE AND LANOSTANE DERIVATIVES: ANTIMICROBIAL EVALUATION

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    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

    Scaling Laws for Mitotic Chromosomes

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    During mitosis in higher eukaryotes, each chromosome condenses into a pair of rod-shaped chromatids. This process is co-regulated by the activity of several gene families, and the underlying biophysics remains poorly understood. To better understand the factors regulating chromosome condensation, we compiled a database of mitotic chromosome size and DNA content from the tables and figures of >200 published papers. A comparison across vertebrate species shows that chromosome width, length and volume scale with DNA content to the powers ∌1/4, ∌1/2, and ∌1, respectively. Angiosperms (flowering plants) show a similar length scaling, so this result is not specific to vertebrates. Chromosome shape and size thus satisfy two conditions: (1) DNA content per unit volume is approximately constant and (2) the cross-sectional area increases proportionately with chromosome length. Since viscous drag forces during chromosome movement are expected to scale with length, we hypothesize that the cross-section increase is necessary to limit the occurrence of large chromosome elongations that could slow or stall mitosis. Lastly, we note that individual vertebrate karyotypes typically exhibit a wider range of chromosome lengths as compared with angiosperms

    Tele-Psychiatry Assessment of Post-traumatic Stress Symptoms in 100 Patients With Bipolar Disorder During the COVID-19 Pandemic Social-Distancing Measures in Italy

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    The acute phase of the COrona VIrus Disease-19 (COVID-19) emergency determined relevant stressful burdens in psychiatric patients, particularly those with chronic mental disorders such as bipolar disorder (BD), not only for the threat of being infected but also for the strict lock-down and social-distancing measures adopted, the economic uncertainty, and the limited possibilities to access psychiatric services. In this regard, telepsychiatry services represented a new important instrument that clinicians could adopt to monitor and support their patients. The aim of the present study was to investigate acute post-traumatic stress symptoms (PTSS) reported by patients with BD followed in the framework of a telepsychiatry service, set up in the acute phase of the COVID-19 outbreak at the psychiatric clinic of the University of Pisa (Italy). A sample of 100 patients were consecutively enrolled and assessed by the IES-r, GAD-7, HAM-D, and YMRS. Patients reported a mean (±SD) IES-r total score of 18.15 ± 13.67. Further, 17% of the sample reported PTSS (IES-r > 32), 17% depressive symptoms (HAM-D > 17), and 26% anxiety symptoms (GAD-7 > 10). Work and financial difficulties related to the COVID-19 pandemic and anxiety symptoms appeared to be positively associated with the development of acute PTSS. Acute manic symptoms appeared to be protective. The data of the present study suggest the relevance of monitoring patients with BD exposed to the burden related to the COVID-19 outbreak for prompt assessment and treatment of PTSS

    Spatial-Related Community Structure and Dynamics in Phytoplankton of the Ross Sea, Antarctica

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    The Ross Sea exhibits the largest continental shelf and it is considered to be the most productive region in Antarctica, with phytoplankton communities that have so far been considered to be driven by the seasonal dynamics of the polynya, producing the picture of what is considered as the classical Antarctic food web. Nevertheless, the Ross Sea is made up of a complex mosaic of sub-systems, with physical, chemical, and biological features that change on different temporal and spatial scales. Thus, we investigated the phytoplankton community structure of the Ross Sea with a spatial scale, considering the different ecological sub-systems of the region. The total phytoplankton biomass, maximum quantum efficiency (Fv/Fm), size classes, and main functional groups were analyzed in relation to physical–chemical properties of the water column during the austral summer of 2017. Data from our study showed productivity differences between polynyas and other areas, with high values of biomass in Terra Nova Bay (up to 272 mg chl a m–2) and the south-central Ross Sea (up to 177 mg chl a m–2) that contrast with the HNLC nature of the off-shore waters during summer. Diatoms were the dominant group in all the studied subsystems (relative proportion ≄ 50%) except the southern one, where they coexisted with haptophytes with a similar percentage. Additionally, the upper mixed layer depth seemed to influence the level of biomass rather than the dominance of different functional groups. However, relatively high percentages of dinoflagellates (∌30%) were observed in the area near Cape Adare. The temporal variability observed at the repeatedly sampled stations differed among the sub-systems, suggesting the importance of Long-Term Ecological Research (L-TER) sites in monitoring and studying the dynamics of such an important system for the global carbon cycle as the Ross Sea. Our results provide new insights into the spatial distribution and structure of phytoplankton communities, with different sub-systems following alternative pathways for primary production, identifiable by the use of appropriate sampling scales

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

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    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

    Some polynomial special cases for the Minimum Gap Graph Partitioning Problem

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    We study various polynomial special cases for the problem of partitioning a vertex-weighted undirected graph into p connected subgraphs with minimum gap between the largest and the smallest vertex weight

    Uniform partition of graphs: Complexity results, algorithms and formulations

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    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

    Subsurface life can modify volatile cycling on a planetary scale

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    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.. UniversitĂ  degli Studi di Napoli Federico II; Italia. Tokyo Institute of Technology; JapĂłn. 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 CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico 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.. UniversitĂ  degli Studi di Napoli Federico II; ItaliaFil: Covone, G.. UniversitĂ  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

    Plasma from pre-pubertal obese children impairs insulin stimulated Nitric Oxide (NO) bioavailability in endothelial cells: Role of ER stress.

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    Childhood obesity is commonly associated with early signs of endothelial dysfunction, characterized by impairment of insulin signaling and vascular Nitric Oxide (NO) availability. However, the underlying mechanisms remain to be established. Hence, we tested the hypothesis that endothelial insulin-stimulated NO production and availability was impaired and related to Endoplasmic Reticulum (ER) in human umbilical vein endothelial cells (HUVECs) cultured with plasma obtained from pre-pubertal obese (OB) children. OB children (N = 28, age: 8.8 ± 2.2; BMI z-score: 2.15 ± 0.39) showed impaired fasting glucose, insulin and HOMA-IR than normal weight children (CTRL; N = 28, age: 8.8 ± 1.7; BMI z-score: 0.17 ± 0.96). The in vitro experiments showed that OB-plasma significantly impaired endothelial insulin-stimulated NO production and bioavailability compared to CTRL-plasma. In parallel, in HUVECs OB-plasma increased GRP78 and activated PERK, eIF2α, IkBα and ATF6 (all ER stress markers). Moreover, OB-plasma increased NF-ÎșB activation and its nuclear translocation. Notably, all these effects proved to be significantly restored by using PBA and TUDCA, known ER stress inhibitors. Our study demonstrate for the first time that plasma from obese children is able to induce in vitro endothelial insulin resistance, which is characterized by reduced insulin-stimulated NO production and bioavailability, endothelial ER stress and increased NF-ÎșB activation
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