Recuperação da vegetação de caatinga após impacto em Assaré - CE

Recuperação da vegetação de caatinga apósimpacto em Assaré - C

Fitofiosionomia de uma caatinga no município de Milagres, CE

Fitofiosionomia de uma caatinga nomunicípio de Milagres, C

Caracterização de uma vegetação de cerrado em uma área no município de Nova Olinda-CE

Caracterização de uma vegetação de cerrado em umaárea no município de Nova Olinda-C

Fluctuations, dissipation and the dynamical Casimir effect

Vacuum fluctuations provide a fundamental source of dissipation for systems coupled to quantum fields by radiation pressure. In the dynamical Casimir effect, accelerating neutral bodies in free space give rise to the emission of real photons while experiencing a damping force which plays the role of a radiation reaction force. Analog models where non-stationary conditions for the electromagnetic field simulate the presence of moving plates are currently under experimental investigation. A dissipative force might also appear in the case of uniform relative motion between two bodies, thus leading to a new kind of friction mechanism without mechanical contact. In this paper, we review recent advances on the dynamical Casimir and non-contact friction effects, highlighting their common physical origin.Comment: 39 pages, 4 figures. Review paper to appear in Lecture Notes in Physics, Volume on Casimir Physics, edited by Diego Dalvit, Peter Milonni, David Roberts, and Felipe da Rosa. Minor changes, a reference adde

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time, and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space. While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes, vast areas of the tropics remain understudied. In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity, but it remains among the least known forests in America and is often underrepresented in biodiversity databases. To worsen this situation, human-induced modifications may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge, it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Características de carcaça e dos componentes não-carcaça de cabritos Moxotó e Canindé submetidos a dois níveis de alimentação Characteristics of carcass and non-carcass components of Moxotó and Canindé male kids under two feeding levels

Foram utilizados 22 cabritos não-castrados (10 Moxotó e 12 Canindé com peso médio inicial de 15 kg) confinados em baias individuais. Os animais foram distribuídos em um delineamento inteiramente casualizado, em arranjo fatorial 2 x 2 (duas raças e dois níveis de alimentação: AV = à vontade e AR = 30% de restrição). Foram avaliados os rendimentos de carcaça quente (RCQ), verdadeiro (RV) e comercial (RC), os cortes da carcaça e o rendimento dos componentes não-carcaça em relação ao peso do corpo vazio (PCV). Cabritos alimentados à vontade apresentaram maiores RCQ e RC e porções comestíveis da carcaça. O rendimento verdadeiro não foi influenciado pelo maior nível de alimentação. Após o abate e resfriamento da carcaça, foram feitos os seguintes cortes: pescoço, paleta, costelas (1ª-5ª), costelas (6ª-13ª), lombo, perna e baixo. Apesar do maior peso (kg) dos cortes dos animais alimentados AV, não foi observada diferença entre seus rendimentos em relação ao peso da carcaça fria. O rendimento da perna foi afetado pelo nível de alimentação, sendo menor para os grupos com nível de alimentação AV. Os rendimentos do fígado, da cabeça e do trato gastrintestinal foram influenciados pelo nível de alimentação. A raça não foi determinante de diferenças nas características de carcaça e dos componentes não-carcaça, assim como no rendimento dos cortes quando o peso e o tamanho à maturidade foram semelhantes. A restrição alimentar afetou o desenvolvimento e a deposição de tecidos nos animais, resultando em menores rendimentos e quilogramas de carcaça fria a ser comercializada.<br>Twenty-two non-castrated male kids (10 Moxotó and 12 Canindé) averaging 15 kg of initial body weight and housed in individual pens were used in this trial. Animals were assigned to a completely randomized design in a 2 x 2 factorial arrangement of treatments [two breeds and two feeding levels: ad libitum (AL) or 30% of feed restriction (FR). Animals fed AL had greater yields of hot carcass, cold carcass, and carcass edible parts compared to those fed FR. It was not observed a significant feeding level effect on true carcass yield. After slaughter and cooling of the carcasses the following cuts were done: neck, shoulder clod, ribs (1st-5th and 6th-13th), loin, leg and breast. Although animals fed AL had greater body weights than FR kids, no significant differences were found between treatments for the different carcass cuts when expressed as percentage of cold carcass weight. Hind leg yield was affected by feeding level being lower in animals fed AL. Yields of liver, head, and gut, as percentage of empty body weight, were also affected by feeding level. Feed restriction had a negative effect on development and tissue deposition leading to lower cold carcass yield and weight. It can be concluded that when size and mature weight were similar, breed was not responsible for the differences on carcass characteristics, non-carcass components, and commercial cuts