Direct calorimetric measurements of isothermal entropy change on single crystal W-type hexaferrites at the spin reorientation transition

We report on the magnetic field induced isothermal entropy change, \Delta s(Ha, T), of W-type ferrite with CoZn substitution. Entropy measurements are performed by direct calorimetry. Single crystals of the composition BaCo$_0.62$Zn$_1.38$Fe$_16$O$_27$, prepared by the flux method, are measured at different fixed temperatures under an applied field perpendicular and parallel to the c axis. At 296 K one deduces a value of K$_1$ = 8.7 \times 10^{4} J m$^-3$ for the first anisotropy constant, which is in good agreement with the literature. The spin reorientation transition temperature is estimated to take place between 200 and 220 K

Grapevine virus diseases: economic impact and current advances in viral prospection and management.

Grapevine (Vitis spp.) is a major vegetative propagated fruit crop with high socioeconomic importance worldwide. It is susceptible to several graft-transmitted agents that cause several diseases and substantial crop losses, reducing fruit quality and plant vigor, and shorten the longevity of vines. ] The vegetative propagation and frequent exchanges of propagative material among countries contribute to spread these pathogens, favoring the emergence of complex diseases. Its perennial life cycle further accelerates the mixing and introduction of several viral agents into a single plant. Currently, approximately 65 viruses belonging to different families have been reported infecting grapevines, but not all cause economically relevant diseases. The grapevine leafroll, rugose wood complex, leaf degeneration and fleck diseases are the four main disorders having worldwide economic importance. In addition, new viral species and strains have been identified and associated with economically important constraints to grape production. In Brazilian vineyards, eighteen viruses, three viroids and two virus-like diseases had already their occurrence reported and were molecularly characterized. Here, we review the current knowledge of these viruses, report advances in their diagnosis and prospection of new species, and give indications about the management of the associated grapevine diseases. Index terms: Vegetative propagation, plant viruses, crop losses, berry quality, next-generation sequencing. VIROSES EM VIDEIRAS: IMPACTO ECONÔMICO E RECENTES AVANÇOS NA PROSPECÇÃO DE VÍRUS E MANEJO DAS DOENÇAS DE ORIGEM VIRAL A videira (Vitis spp.) é propagada vegetativamente e considerada uma das principais culturas frutíferas por sua importância socioeconômica mundial. Ela é suscetível a vários agentes transmitidos por meio da enxertia, os quais causam diversas doenças e significativas perdas na produtividade e produção, redução na qualidade dos frutos, no vigor da planta e na longevidade dos vinhedos. A propagação vegetativa e o frequente intercâmbio de material propagativo entre países contribuem para a disseminação destes patógenos, favorecendo a emergência de doenças complexas. Seu ciclo de vida perene acelera ainda mais a mistura e a introdução de vários agentes virais em uma mesma planta. Atualmente, aproximadamente 65 vírus pertencentes a diferentes famílias foram reportados infectando videiras, embora nem todos causem doenças economicamente relevantes. As viroses do enrolamento da folha, complexo do lenho rugoso, degenerescência e mancha-das-nervuras da videira são as quatro principais desordens que têm importância econômica mundial. Além disso, novas espécies e estirpes virais foram identificadas e associadas a limitações economicamente importantes para a produção de uvas. Em vinhedos brasileiros, dezoito espécies virais, três viroides e duas doenças semelhantes a viroses já tiveram sua ocorrência reportada e foram molecularmente caracterizados. Aqui, nós revisamos o conhecimento atual dessas viroses, os recentes avanços na diagnose e prospecção viral, e fornecemos recomentações sobre o manejo das viroses da videira. Termos para indexação: Propagação vegetativa, vírus de plantas, redução da produtividade e produção, qualidade das bagas, sequenciamento de nova geração

Inclusive gauge boson production in the color dipole formalism

The inclusive production of the gauge bosons $W^{\pm}$ and $Z^0$ is studied within the color dipole formalism. Gluon saturation effects associated to non-linear corrections to the QCD dynamics, which are expected to contribute at high energies, are naturally included in such formalism. We estimate the contribution of these effects at LHC energies and compare our results with the next-to-next-to-leading order collinear predictions. A comparison with the current experimental data is performed and predictions for higher energies are presented.Comment: 12 pages, 6 figures, 2 tables. Version to be published in Physical Review

Explicit models for flexural edge and interfacial waves in thin elastic plates

In the thesis explicit dual parabolic-elliptic models are constructed for the Konenkov flexural edge wave and the Stoneley-type flexural interfacial wave in case of thin linearly elastic plates. These waves do not appear in an explicit form in the original equations of motion within the framework of the classical Kirchhoff plate theory. The thesis is aimed to highlight the contribution of the edge and interfacial waves into the overall displacement field by deriving specialised equations oriented to aforementioned waves only. The proposed models consist of a parabolic equation governing the wave propagation along a plate edge or plate junction along with an elliptic equation over the interior describing decay in depth. In this case the parabolicity of the one-dimensional edge and interfacial equations supports flexural wave dispersion. The methodology presented in the thesis reveals a dual nature of edge and interfacial plate waves contrasting them to bulk-type wave propagating in thin elastic structures. The thesis tackles a number of important examples of the edge and interfacial wave propagation. First, it addresses the propagation of Konenkov flexural wave in an elastic isotropic plate under prescribed edge loading. For the latter, parabolic-elliptic explicit models were constructed and thoroughly investigated. A similar problem for a semi-infinite orthotropic plate resulted in a more general dual parabolic-elliptic model. Finally, an anal- ogous model was derived and analysed for two isotropic semi-infinite Kirchhoff plates under perfect contact conditions.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Strategies for achieving sustainable logging rate in the Brazilian Amazon Forest.

Data of increment of the remnant trees after logging, ingrowth and mortality was obtained by assessment before logging and after 6 years, two sites of 50 ha, in Amazon forest. Logging scenarios were simulated to identify the logging rate potential for each studying sites, by diameter class projection method. The cy- cle of 35 years and the logging rate of 30 m3?ha?1 exceed the time required for recovery in the primary forest, in the studied site. The simulation showed that in the studying area, a well-planned logging, with minimum logging damage would be possible to implement an initial cycle of 25 years to the forest to re- cover 30 m3?ha?1, if 50% of the timber stock were reserved. The forest increment, beyond important fac- tors such as the increase of individual species, is quite dependent on the remnant trees

Pancreatic cancer-associated diabetes mellitus: an open field for proteomic applications.

Background: Diabetes mellitus is associated with pancreatic cancer in more than 80% of the cases. Clinical, epidemiological, and experimental data indicate that pancreatic cancer causes diabetes mellitus by releasing soluble mediators which interfere with both beta-cell function and liver and muscle glucose metabolism. Methods: We analysed, by matrix-assisted laser desorption ionization time of flight (MALDI-TOF), a series of pancreatic cancer cell lines conditioned media, pancreatic cancer patients' peripheral and portal sera, comparing them with controls and chronic pancreatitis patients' sera. Results: MALDI-TOF analysis of pancreatic cancer cells conditioned media and patients' sera indicated a low molecular weight peptide to be the putative pancreatic cancer-associated diabetogenic factor. The sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis of tumor samples from diabetic and non-diabetic patients revealed the presence of a 1500 Da peptide only in diabetic patients. The amino acid sequence of this peptide corresponded to the N-terminal of an S-100 calcium binding protein, which was therefore suggested to be the pancreatic cancer-associated diabetogenic factor. Conclusions: We identified a tumor-derived peptide of 14 amino acids sharing a 100% homology with an S-100 calcium binding protein, which is probably the pancreatic cancer-associated diabetogenic facto

Pancreatic cancer-derived S-100A8 N-terminal peptide: a diabetes cause?

BACKGROUND: Our aim was to identify the pancreatic cancer diabetogenic peptide. METHODS: Pancreatic tumor samples from patients with (n=15) or without (n=7) diabetes were compared with 6 non-neoplastic pancreas samples using SDS-PAGE. RESULTS: A band measuring approximately 1500 Da was detected in tumors from diabetics, but not in neoplastic samples from non-diabetics or samples from non-neoplastic subjects. Sequence analysis revealed a 14 amino acid peptide (1589.88 Da), corresponding to the N-terminal of the S100A8. At 50 nmol/L and 2 mmol/L, this peptide significantly reduced glucose consumption and lactate production by cultured C(2)C(12) myoblasts. The 14 amino acid peptide caused a lack of myotubular differentiation, the presence of polynucleated cells and caspase-3 activation. CONCLUSIONS: The 14 amino acid peptide from S100A8 impairs the catabolism of glucose by myoblasts in vitro and may cause hyperglycemia in vivo. Its identification in biological fluids might be helpful in diagnosing pancreatic cancer in patients with recent onset diabetes mellitus