Modelling the precipitation of NbC on dislocations in a-Fe

A model has been developed for describing the precipitation of NbC on dislocations in ferrite in an Fe–C–Nb steel. This model is a continuous description of the classical laws for nucleation growth and coarsening, which are adapted to the specific case where precipitates only form on dislocations. This model is successfully applied on an extensive data set obtained by small-angle neutron scattering for a wide temperature range and two alloy contents. Using this model, it is possible to estimate the effects of process parameters on the final microstructure and, notably, it is shown that the initial dislocation density has a pronounced influence on the maximum precipitate density

Cytostatic Factor Proteins Are Present in Male Meiotic Cells and β-Nerve Growth Factor Increases Mos Levels in Rat Late Spermatocytes

Background: In co-cultures of pachytene spermatocytes with Sertoli cells, beta-NGF regulates the second meiotic division by blocking secondary spermatocytes in metaphase (metaphase II), and thereby lowers round spermatid formation. In vertebrates, mature oocytes are arrested at metaphase II until fertilization, because of the presence of cytostatic factor (CSF) in their cytoplasm. By analogy, we hypothesized the presence of CSF in male germ cells. Methodology/Principal Findings: We show here, that Mos, Emi2, cyclin E and Cdk2, the four proteins of CSF, and their respective mRNAs, are present in male rat meiotic cells; this was assessed by using Western blotting, immunocytochemistry and reverse transcriptase PCR. We measured the relative cellular levels of Mos, Emi2, Cyclin E and Cdk2 in the meiotic cells by flow cytometry and found that the four proteins increased throughout the first meiotic prophase, reaching their highest levels in middle to late pachytene spermatocytes, then decreased following the meiotic divisions. In co-cultures of pachytene spermatocytes with Sertoli cells, beta-NGF increased the number of metaphases II, while enhancing Mos and Emi2 levels in middle to late pachytene spermatocytes, pachytene spermatocytes in division and secondary spermatocytes. Conclusion/Significance: Our results suggest that CSF is not restricted to the oocyte. In addition, they reinforce the view that NGF, by enhancing Mos in late spermatocytes, is one of the intra-testicular factors which adjusts the number of round spermatids that can be supported by Sertoli cells

Outcome of Ph negative myeloproliferative neoplasms transforming to accelerated or leukemic phase

Myeloproliferative neoplasms (MPN) are chronic disorders that can sometimes evolve into accelerated or leukemic phases. We retrospectively identified 122 patients with such blastic phases. The overall median survival was four months: 10.2 months for patients treated with intensive treatments compared to three months for best supportive care (p = .005). Azacytidine, intensive chemotherapies, or allogeneic stem cell transplantation gave the highest median survivals with 9, 10.2, and 19.4 months, respectively. Accelerated phases (AP) had a longer median survival compared to acute leukemia (4.8 months vs. 3.1 months; p = .02). In this retrospective and observational study, we observe that the longest survivals are seen in patients eligible for intensive treatments. Azacytidine shows interesting results in patients non-fit for intensive chemotherapy. Supportive care should probably be restricted to elderly patients and those with unfavorable karyotype. An early diagnosis of AP could also result in a better survival rate

EXPAND, a dose-finding study of ruxolitinib in patients with myelofibrosis and low platelet counts: 48-week follow-up analysis

EEXPAND (phase Ib, dose-finding study) evaluated the starting dose of ruxolitinib in patients with myelofibrosis with baseline platelet counts of 50-99×109 /L. The study consisted of dose-escalation and safety-expansion phases. Based on the baseline platelet counts, patients were assigned to stratum 1 (75-99x109 /L) or stratum 2 (50-74x109 /L), with the primary objective of determining the maximum safe starting dose (MSSD); key secondary objectives included safety and efficacy. At week 48 data cutoff (stratum 1, n=44; stratum 2, n=25), 24.6% (17 out of 69) of patients were still receiving treatment. The MSSD was established as ruxolitinib 10 mg twice daily in both strata. Thrombocytopenia [grade 4 (stratum 1, n=1; stratum 2, n=2)] was the only reported dose-limiting toxicity (study drug related) at 10 mg twice daily. In the MSSD cohort (stratum 1, n=20; stratum 2, n=18), adverse events (regardless of study drug relationship) led to treatment discontinuation in 15.0% and 33.3% of patients in stratum 1 and stratum 2, respectively, and dose adjustment/interruption in 45.0% and 66.7% of patients in stratum 1 and stratum 2, respectively. Three cases of on-treatment deaths were reported at the MSSD. Spleen response was achieved at week 48 in 33.3% and 30.0% of patients in stratum 1 and stratum 2, respectively. Improvements in the Total Symptom Score were also observed. In this study, ruxolitinib demonstrated acceptable tolerability in both the strata at the MSSD of 10 mg twice daily. (Registered at: clinicaltrials.gov identifier: 01317875)

National records of 3000 European bee and hoverfly species: A contribution to pollinator conservation

Pollinators play a crucial role in ecosystems globally, ensuring the seed production of most flowering plants. They are threatened by global changes and knowledge of their distribution at the national and continental levels is needed to implement efficient conservation actions, but this knowledge is still fragmented and/or difficult to access. As a step forward, we provide an updated list of around 3000 European bee and hoverfly species, reflecting their current distributional status at the national level (in the form of present, absent, regionally extinct, possibly extinct or non-native). This work was attainable by incorporating both published and unpublished data, as well as knowledge from a large set of taxonomists and ecologists in both groups. After providing the first National species lists for bees and hoverflies for many countries, we examine the current distributional patterns of these species and designate the countries with highest levels of species richness. We also show that many species are recorded in a single European country, highlighting the importance of articulating European and national conservation strategies. Finally, we discuss how the data provided here can be combined with future trait and Red List data to implement research that will further advance pollinator conservation

Modelling the precipitation of NbC on dislocations in a-Fe

International audienceA model has been developed for describing the precipitation of NbC on dislocations in ferrite in an Fe–C–Nb steel. This model is a continuous description of the classical laws for nucleation growth and coarsening, which are adapted to the specific case where precipitates only form on dislocations. This model is successfully applied on an extensive data set obtained by small-angle neutron scattering for a wide temperature range and two alloy contents. Using this model, it is possible to estimate the effects of process parameters on the final microstructure and, notably, it is shown that the initial dislocation density has a pronounced influence on the maximum precipitate density