On the geometry of moduli spaces of coherent systems on algebraic curves

Let $C$ be an algebraic curve of genus $g$. A coherent system on $C$ consists of a pair $(E,V)$, where $E$ is an algebraic vector bundle over $C$ of rank $n$ and degree $d$ and $V$ is a subspace of dimension $k$ of the space of sections of $E$. The stability of the coherent system depends on a parameter $\alpha$. We study the geometry of the moduli space of coherent systems for different values of $\alpha$ when $k\leq n$ and the variation of the moduli spaces when we vary $\alpha$. As a consequence, for sufficiently large $\alpha$, we compute the Picard groups and the first and second homotopy groups of the moduli spaces of coherent systems in almost all cases, describe the moduli space for the case $k=n-1$ explicitly, and give the Poincar\'e polynomials for the case $k=n-2$.Comment: 38 pages; v3. Appendix and new references added; v4. minor corrections, two added references; v5. final version, one typo corrected and one reference delete

Analysis of air mass dependence of three photovoltaic arrays

The solar spectrum, which is also could be described by air mass factor, has a significant relationship with the performance of photovoltaic modules. The air mass dependence has been investigated by a theoretical method as well as an actual case of three different photovoltaic arrays: polycrystalline silicon, amorphous silicon and cadmium telluride, at the EUIT Agrícola-UPM (Madrid, Spain, 40.4426oN, 3.7295oW). The calculating results show that: AM dependence of poly-Si array is positive because an elevating AM-value indicates a red shift and poly-Si module is more red sensitive; On the contrary, as a-Si module and CdTe module are more blue sensitive, their AM dependences are negative. Furthermore, the outdoor AM dependences of three arrays are corresponding to the calculating results although the thermal annealing effect could be superimposed on spectral effect in the case of a-Si. Keywords: PV system, spectral response, polycrystalline silicon, a-Si, CdT

Wiping DNA Methylation: Wip1 Regulates Genomic Fluidity on Cancer

Wip1 phosphatase plays an important role in cancer by inactivating p53 and INK4a/ARF pathways. In this issue of Cancer Cell, Filipponi and colleagues further connect the oncogenic role of Wip1 with heterochromatin dynamics, transposable element expression, and a mutation-prone environment that may enhance heterogeneity and ultimately contribute to tumor evolution

Economic feasibility analysis of choices for not connected clients: photovoltaic off-grid systems, compared to grid based system

Off-grid photovoltaic systems are less constrained by national regulations than their grid-connected counterparts. Off-grid systems do not depend on feed-in tariff and the analysis of their cost-efficiency is more stable along time. This work calculates the economic parameters for two different technologies of photovoltaic systems and compares the levelized cost of electricity (LCOE), with the price of the electricity, including the cost for the connection of the system related to the distance to the grid. The results show that the sustained decline in photovoltaic module¿s price contributes to subsequent decline in LCOE, whereas the increase in the price of grid electricity and materials related to the connection makes off-grid systems more cost-effective for remote areas. Finally, to determine if the photovoltaic system could be an economic alternative for investments in remote regions, a comparison between the cost of grid extension and the LCOE of a high capacity photovoltaic system was undertaken

The importance of the lipoxygenase-hepoxilin pathway in the mammalian epidermal barrier

This review covers the background to discovery of the two key lipoxygenases (LOX) involved in epidermal barrier function, 12R-LOX and eLOX3, and our current views on their functioning. In the outer epidermis, their consecutive actions oxidize linoleic acid esterified in ω-hydroxy-ceramide to a hepoxilin-related derivative. The relevant background to hepoxilin and trioxilin biochemistry is briefly reviewed. We outline the evidence that linoleate in the ceramide is the natural substrate of the two LOX enzymes and our proposal for its importance in construction of the epidermal water barrier. Our hypothesis is that the oxidation promotes hydrolysis of the oxidized linoleate moiety from the ceramide. The resulting free ω-hydroxyl of the ω-hydroxyceramide is covalently bound to proteins on the surface of the corneocytes to form the corneocyte lipid envelope, a key barrier component. Understanding the role of the LOX enzymes and their hepoxilin products should provide rational approaches to ameliorative therapy for a number of the congenital ichthyoses involving compromised barrier function. This article is part of a Special Issue entitled The Important Role of Lipids in the Epidermis and their Role in the Formation and Maintenance of the Cutaneous Barrier. Guest Editors: Kenneth R. Feingold and Peter Elias

Lurbinectedin in patients with pretreated neuroendocrine tumours: Results from a phase II basket study

Lurbinectedin; Neuroendocrine tumours; Small cellLurbinectedina; Tumores neuroendocrinos; Célula pequeñaLurbinectedina; Tumors neuroendocrins; Cèl·lula petitaBackground Patients with neuroendocrine tumours (NETs) need alternative therapies after failure of first-line therapy. Patients and methods This phase II trial evaluated lurbinectedin, a selective inhibitor of oncogenic transcription, at 3.2 mg/m2 as a 1-h intravenous infusion every 3 weeks in 32 NETs patients treated in the second- or third-line setting. The primary efficacy endpoint was overall response rate (ORR) according to RECIST v1.1 assessed by the investigators. Secondary endpoints included duration of response (DoR), progression-free survival (PFS), overall survival (OS) and safety. Results Two of 31 evaluable patients had confirmed partial responses (ORR = 6.5%; 95%CI, 0.8–21.4%). Median DoR was 4.7 months (95% CI, 4.0–5.4 months), median PFS was 1.4 months (95% CI, 1.2–3.0 months) and median OS was 7.4 months (95% CI, 3.4–16.2 months). Lurbinectedin showed an acceptable, predictable and manageable safety profile. The most common grade 3/4 toxicity was neutropenia (40.6%; grade 4, 12.4%; febrile neutropenia, 3.1%). Conclusions Considering the exploratory aim of this trial that evaluated a heterogeneous population of NETs patients, and the signs of antitumour activity observed (two confirmed partial responses and seven long disease stabilisations), further development of lurbinectedin is warranted in a more selected NETs population

Radiation-damage produced in BaHfO₃ irradiated with thermal and fast-neutrons

Samples of BaHfO₃ were irradiated with fast and thermal neutrons to produce ^181Hf. Attenuations of the gamma-gamma perturbed angular correlations in ^181Ta were observed, and they may have been caused by the interaction between defects (produced during or after neutron irradiation) and oxygen vacancies. Several defect structures were detected. For one of the structures, an excitation energy of 12 meV was measured, which was attributed to an electron state below the conduction band. The values of the dielectric constant and of the effective electron mass were also deduced