Anomalies in orbifold field theories

We study the constraints on models with extra dimensions arising from local anomaly cancellation. We consider a five-dimensional field theory with a U(1) gauge field and a charged fermion, compactified on the orbifold S^1/(Z_2 x Z_2'). We show that, even if the orbifold projections remove both fermionic zero modes, there are gauge anomalies localized at the fixed points. Anomalies naively cancel after integration over the fifth dimension, but gauge invariance is broken, spoiling the consistency of the theory. We discuss the implications for realistic supersymmetric models with a single Higgs hypermultiplet in the bulk, and possible cancellation mechanisms in non-minimal models.Comment: 10 pages, 2 figures, LaTex; v2: final version to be published in Phys. Lett.

Areias quartzosas da bacia do Ribeirão do Lobo (Brotas-Itirapina, SP) II: características mineralógicas e químicas

Aspectos mineralógicos e químicos foram estudados em três perfis de Areias Quartzosas localizados em uma toposequência da Bacia do Ribeirão do Lobo, nos municípios de Brotas e Itirapina, no Estado de São Paulo. A homogeneidade mineralógica observada entre os horizontes e entre os perfis permite que se conclua serem estes solos derivados do mesmo material de origem. A maturidade mineralógica e arredondamento dos grãos do resíduo pesado indicam que os solos estudados sofreram a mesma intensidade de transporte. Quimicamente são solos distróficos, caracterizados por reação ácida, baixos valores de soma de bases e elevada saturação com alumínio,determinando caráter álico.Chemical and mineralogical characteristics of three Psammic Soils occurring in the Lobo Creek Basin, situated at different topographic levels in Itirapina and Brotas municipalities were studied. The mineralogical homogeneity observed between horizons and profiles allows for the conclusion that these soils are derived from the same kind of parent material. The mineralogical maturity and the degree of roundness of the heavy residue indicate that these soils were subjected to the same intensity of transport. The chemical characteristics indicate that the soils present acid reaction and a distrophic and an alic character

Intracerebral Injection of Extracellular Vesicles from Mesenchymal Stem Cells Exerts Reduced Aβ Plaque Burden in Early Stages of a Preclinical Model of Alzheimer's Disease

Bone marrow Mesenchymal Stem Cells (BM-MSCs), due to their strong protective and anti-inflammatory abilities, have been widely investigated in the context of several diseases for their possible therapeutic role, based on the release of a highly proactive secretome composed of soluble factors and Extracellular Vesicles (EVs). BM-MSC-EVs, in particular, convey many of the beneficial features of parental cells, including direct and indirect \u3b2-amyloid degrading-activities, immunoregulatory and neurotrophic abilities. Therefore, EVs represent an extremely attractive tool for therapeutic purposes in neurodegenerative diseases, including Alzheimer's disease (AD). We examined the therapeutic potential of BM-MSC-EVs injected intracerebrally into the neocortex of APPswe/PS1dE9 AD mice at 3 and 5 months of age, a time window in which the cognitive behavioral phenotype is not yet detectable or has just started to appear. We demonstrate that BM-MSC-EVs are effective at reducing the A\u3b2 plaque burden and the amount of dystrophic neurites in both the cortex and hippocampus. The presence of Neprilysin on BM-MSC-EVs, opens the possibility of a direct \u3b2-amyloid degrading action. Our results indicate a potential role for BM-MSC-EVs already in the early stages of AD, suggesting the possibility of intervening before overt clinical manifestations

Produção da cenoura e efeito na fertilidade do solo e nutrição decorrente da solarização do solo para controle da tiririca.

Dentre os desafios do cultivo orgânico de hortaliças destaca-se o controle de plantas daninhas, devido à proibição do uso de herbicidas. Entre as invasoras, a tiririca (Cyperus rotundus L.) é de difícil controle pela sua alta competitividade. A solarização é uma alternativa para desinfestação do solo, a qual consiste em cobri-lo com plástico transparente, com bons resultados no controle da tiririca. A fim de avaliar a influência do preparo e do revolvimento do solo sobre a eficiência da solarização no controle da tiririca, bem como seu posterior efeito sobre o cultivo da cenoura, foi realizado um experimento na Fazendinha Agroecológica, em Seropédica (RJ). O experimento foi disposto em blocos ao acaso com três repetições, em arranjo fatorial 2 x 3 mais uma testemunha adicional, sendo: 1) solo solarizado, preparado (com grade aradora) e revolvido 30 dias após a solarização (manualmente com auxílio de uma enxada); 2) solo solarizado, preparado e revolvido aos 60 dias; 3) solo solarizado, preparado e não revolvido; 4) solo solarizado, não preparado e revolvido aos 30 dias; 5) solo solarizado, não preparado e revolvido aos 60 dias; 6) solo solarizado, não preparado e não revolvido; solo não solarizado, não preparado e não revolvido (testemunha). A solarização iniciou-se em 29/1/2002, e durou cem dias. A solarização reduziu em 86% a infestação de tiririca no cultivo da cenoura. Até 10 cm de profundidade, a temperatura do solo foi superior nas parcelas solarizadas, porém a 5 cm, a solarização foi mais eficiente quando associada ao preparo do solo, não havendo efeito do revolvimento. A solarização aumentou os valores da biomassa microbiana e dos teores de Ca, Mg e P do solo. O desenvolvimento da cenoura foi influenciado pela solarização que resultou em maior produtividade

RICORS2040 : The need for collaborative research in chronic kidney disease

Chronic kidney disease (CKD) is a silent and poorly known killer. The current concept of CKD is relatively young and uptake by the public, physicians and health authorities is not widespread. Physicians still confuse CKD with chronic kidney insufficiency or failure. For the wider public and health authorities, CKD evokes kidney replacement therapy (KRT). In Spain, the prevalence of KRT is 0.13%. Thus health authorities may consider CKD a non-issue: very few persons eventually need KRT and, for those in whom kidneys fail, the problem is 'solved' by dialysis or kidney transplantation. However, KRT is the tip of the iceberg in the burden of CKD. The main burden of CKD is accelerated ageing and premature death. The cut-off points for kidney function and kidney damage indexes that define CKD also mark an increased risk for all-cause premature death. CKD is the most prevalent risk factor for lethal coronavirus disease 2019 (COVID-19) and the factor that most increases the risk of death in COVID-19, after old age. Men and women undergoing KRT still have an annual mortality that is 10- to 100-fold higher than similar-age peers, and life expectancy is shortened by ~40 years for young persons on dialysis and by 15 years for young persons with a functioning kidney graft. CKD is expected to become the fifth greatest global cause of death by 2040 and the second greatest cause of death in Spain before the end of the century, a time when one in four Spaniards will have CKD. However, by 2022, CKD will become the only top-15 global predicted cause of death that is not supported by a dedicated well-funded Centres for Biomedical Research (CIBER) network structure in Spain. Realizing the underestimation of the CKD burden of disease by health authorities, the Decade of the Kidney initiative for 2020-2030 was launched by the American Association of Kidney Patients and the European Kidney Health Alliance. Leading Spanish kidney researchers grouped in the kidney collaborative research network Red de Investigación Renal have now applied for the Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS) call for collaborative research in Spain with the support of the Spanish Society of Nephrology, Federación Nacional de Asociaciones para la Lucha Contra las Enfermedades del Riñón and ONT: RICORS2040 aims to prevent the dire predictions for the global 2040 burden of CKD from becoming true