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The globally important marine diazotrophic cyanobacterium Trichodesmium is abundant in the New Caledonian lagoon (southwestern Pacific Ocean) during austral spring/summer. We investigated the cellular processes mediating Trichodesmium mortality from large surface accumulations (blooms) in the lagoon. Trichodesmium cells (and associated microbiota) were collected at the time of surface accumulation, enclosed under simulated ambient conditions, and sampled over time to elucidate the stressors and subcellular underpinning of rapid biomass demise (> 90 % biomass crashed within ∼ 24 h). Metatranscriptomic profiling of Trichodesmium biomass, 0, 8 and 22 h after incubations of surface accumulations, demonstrated upregulated expression of genes required to increase phosphorus (P) and iron (Fe) availability and transport, while genes responsible for nutrient storage were downregulated. Total viral abundance oscillated throughout the experiment and showed no significant relationship with the development or demise of the Trichodesmium biomass. Enhanced caspase-specific activity and upregulated expression of a suite of metacaspase genes, as the Trichodesmium biomass crashed, implied autocatalytic programmed cell death (PCD) as the mechanistic cause. Concurrently, genes associated with buoyancy and gas vesicle production were strongly downregulated concomitant with increased production and high concentrations of transparent exopolymeric particles (TEP). The rapid, PCD-mediated, decline of the Trichodesmium biomass, as we observed from our incubations, parallels mortality rates reported from Trichodesmium blooms in situ. Our results suggest that, whatever the ultimate factor, PCD-mediated death in Trichodesmium can rapidly terminate blooms, facilitate aggregation, and expedite vertical flux to depth.

A one-dimensional two-phase Stefan problem for the melting of a semi-infinite material with a power-type temperature-dependent thermal conductivity was considered. The assumption of taking thermal parameters as functions of temperature found its basis in physical and industries applications, allowing for a more precise and realistic description of phase change processes. By imposing a Dirichlet condition at the fixed face, a theoretical and approximate study was developed. Through a similarity transformation, an equivalent ordinary differential problem was obtained from which an integral problem was deduced. The existence of at least one analytical solution was guaranteed by using the Banach fixed point theorem. Due the unavailability of an analytical solution, a heat balance integral method was applied, assuming a quadratic temperature profile in space, to simulate temperature variations and the location of the interface during the melting process. For constant thermal conductivity, results can be compared with the exact solution available in the literature to check the accuracy of the approximate method.

The aim of the study was to compare the efficacy and safety of singledose prulifloxacin vs. single-dose pefloxacin in the treatment of patients with acute uncomplicated urinary tract infections. Two hundred and thirty-one female out-patients were considered microbiologically evaluable and randomly treated with 600 mg prulifloxacin (116 patients) or 800 mg pefloxacin (115 patients). The most commonly isolated uropathogen at baseline was Escherichia coli (71.4%), followed by Proteus mirabilis (10.8%) and Klebsiella pneumoniae (7.8%). Five-seven days posttreatment, the eradication rate was 97.4% and 92.2% in the prulifloxacin and pefloxacin group, respectively. The one-tailed 95% confidence interval analysis showed the equivalence of treatments. Four weeks from treatment no relapses, reinfections or superinfections were observed. The clinical success rates were 92.2% in the prulifloxacin and 84.3% pefloxacin groups. The safety profile was very good with both drugs. The results of the study make it possible to consider prulifloxacin a possible therapeutic option in patients with acute uncomplicated UTIs.

We consider two one-phase nonlinear one-dimensional Stefan problems for a semi-infinite material x > 0; with phase change temperature Tf : We assume that the heat capacity and the thermal conductivity satisfy a Storm’s condition. In the first case, we assume a heat flux boundary condition of the type [PLEASE CHECK FORMULA IN THE PDF], and in the second case, we assume a temperature boundary condition T = Ts < Tf at the fixed face. Solutions of similarity type are obtained in both cases, and the equivalence of the two problems is demonstrated. We also give procedures in order to compute the explicit solution.

Abstract  This study describes an original surgical technique for the correction of medium/high-degree cystocele using a tension-free way to apply a polypropylene mesh: the “tension-free cystocele repair” (TCR). About 218 patients were available with a mean follow-up of 38 months. This technique showed an elevated rate of anatomic correction (75.7%), a statistically significant correction of storage symptoms (48.6 vs 32.5%, p p p [ABSTRACT FROM AUTHOR]

Mechanical forces, acting on eukaryotic cells, are responsible for cell shape, cell proliferation, cell polarity, and cell differentiation thanks to two cells abilities known as mechanosensing and mechanotransduction. Mechanosensing consists of the ability of a cell to sense mechanical cues, while mechanotransduction is the capacity of a cell to respond to these signals by translating mechanical stimuli into biochemical ones. These signals propagate from the extracellular matrix to the nucleus with different well known physical connections, but how the mechanical signals are transduced into biochemical ones remains an open challenge. Recent findings showed that the cell-generated forces affect the translocation of transcription factors (TFs) from the cytoplasm to the nucleus. This mechanism is affected by the features of nuclear pore complexes. Owing to the complex patterns of strains and stresses of the nuclear envelope caused by cytoskeletal forces, it is likely that the morphology of NPC changes as cytoskeleton assemblies’ change. This may ultimately affect molecular transport through the nucleus, hence altering cell functions. Among the various TFs, Yes-associated protein (YAP), which is typically involved in cell proliferation, survival, and differentiation, is able to activate specific pathways when entrapped into the cell nucleus. Here, starting from experimental results, we develop a multiscale finite element (FE) model aimed to simulate the macroscopic cell spreading and consequent changes in the cell mechanical behaviour to be related to the NPCs changes and YAP nuclear transport.

In this article, we define a p-generalized modified error function as the solution to a non-linear ordinary differential equation of second order, with a Robin type boundary condition at x=0. We prove existence and uniqueness of a non-negative $C^{\infty}$ solution by using a fixed point argument. We show that the p-generalized modified error function converges to the p-modified error function defined as the solution to a similar problem with a Dirichlet boundary condition. In both problems, for p=1, the generalized modified error function and the modified error function are recovered. In addition, we analyze the existence and uniqueness of solution to a problem with a Neumann boundary condition.

The extracellular microenvironment proved to exert a potent regulatory effect over different aspects of Embryonic Stem Cells (ESCs) behavior. In particular, the employment of engineered culture surfaces aimed at modulating ESC self-organization resulted effective in directing ESCs toward specific fate decision. ESCs fluctuate among different levels of functional potency and in this context the Zscan4 gene marks the so-called “metastate,” a cellular state in which ESCs retain both self-renewal and pluripotency capabilities. Here we investigated the impact of topographic cues on ESCs pluripotency, differentiation and organization capabilities. To this aim, we engineered culturing platforms of nanograted surfaces with different features size and we investigated their impact on ESCs multicellular organization and Zscan4 gene expression. We showed that the morphology of ESC-derived aggregates and Zscan4 expression are strictly intertwined. Our data suggest that ESC Zscan4 metastate can be promoted if the adhesive surface conditions guide cellular self-aggregation into 3D dome-like structure, in which both cell-material interactions and cell-cell contact are supportive for Zscan4 expression.

A systematic European Union (EU)-wide data framework for the collection of fisheries data in support of the EU Common Fisheries Policy (CFP) was first implemented in 2002. Since that time, EU data collection regulation has undergone 2 revisions in response to evolving policy needs. The European Commission’s Joint Research Centre (JRC) is responsible for conducting research and providing advice on fisheries management under the CFP, and since 2005 has worked closely with the Scientific, Technical and Economic Committee for Fisheries (STECF). JRC and STECF have an open data policy, and aggregated data submitted by EU member states in response to data calls issued under the provisions of the data collection regulation are published via the website of the STECF. This paper provides an overview of the fisheries data activities carried out by the JRC in support of and in collaboration with the STECF and discusses some of the benefits and drawbacks of such activities.