Vortex-Antivortex Lattice in Ultra-Cold Fermi Gases

We discuss ultra-cold Fermi gases in two dimensions, which could be realized in a strongly confining one-dimensional optical lattice. We obtain the temperature versus effective interaction phase diagram for an s-wave superfluid and show that, below a certain critical temperature T_c, spontaneous vortex-antivortex pairs appear for all coupling strengths. In addition, we show that the evolution from weak to strong coupling is smooth, and that the system forms a square vortex-antivortex lattice at a lower critical temperature T_M.Comment: Submitted to Physical Review Letter

Why business angels reject investment opportunities: Is it personal?

A major focus of research on business angels has examined their decision-making processes and investment criteria. As business angels reject most of the opportunities that they receive, this article explores the reasons informing such decisions. In view of angel heterogeneity, investment opportunities might be expected to be rejected for differing reasons. Two sources of data are used to examine this issue. Face-to-face interviews with 30 business angels in Scotland and Northern Ireland provided information on typical ‘deal killers’. This was complemented by an Internet survey of United Kingdom that attracted responses from 238 UK business angels. The findings confirm that the main reason for rejection relates to the entrepreneur/management team. However, angel characteristics do not explain the number of reasons given for opportunity rejection nor do they predict the reasons for rejecting investment opportunities. This could be related to the increasing trend for business angels to join organised groups which, in turn, leads to the development of a shared repertoire of investment approaches. We suggest the concept of ‘communities-of-practice’ as an explanation for this finding

Capacidade de troca de cátions das principais classes de solos da Amazônia, determinada a diferentes valores de pH.

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Efeito da inundação sobre as propriedades de um gleissolo salico sodico de várzea do rio dos Morcegos, no município de Primavera, PA.

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Avaliação da resistência à ferrugem em progênies de cafeeiro F4 obtidas por cruzamentos de 'icatu' com catimor.

Com o objetivo de selecionar progênies de cafeeiro resistentes à ferrugem foram instalados e conduzidos experimentos em Três Pontas, São Sebastião do Paraíso e Machado. Foram avaliadas 17 progênies desenvolvidas pelo programa de Melhoramento Genético do Cafeeiro em Minas Gerais, coordenado pela EPAMIG e obtidas pelo cruzamento ?Icatu? x Catimor, e a cultivar Rubi MG 1192 utilizada como testemunha. O delineamento foi o de blocos casualizados com três repetições. Foram analisadas as características incidência da ferrugem no primeiro semestre de 2006.Os resultados obtidos permitem verificar que as progênies avaliadas apresentam variabilidade para a resistência a ferrugem, isso é confirmado pelas estimativas da herdabilidade que foram de boa magnitude, chegando até o valor de 92,8%. Essa condição aliada à baixa incidência da doença apresentada por algumas progênies, demonstrou que é possível selecionar progênies superiores em relação à resistência a ferrugem na população estudada

Criopreservação de Ovócitos e o Impacto da Pandemia COVID‑19

Egg freezing has evolved over the last decades, becoming an accepted and recognized technique for fertility preservation. This technique has various medical and non ‑medical indications and it is becoming an important step in overcoming age‑related de‑clines in fertility. Nonetheless, since it remains inadequately understood by the general public and medical professionals, raising its awareness is of vital importance. There are numerous factors that influence the technique’s success, particularly the number of matured eggs retrieved and the woman’s age, which affects the quantity and quality of oocytes. Women were prompted to more seriously contemplate social egg freezing throughout the COVID‑19 pandemic, given that social isolation complicated their search for an ideal male partner and allowed for more time to consider and research this topic.info:eu-repo/semantics/publishedVersio