Self-assembly of pseudo-dipolar nanoparticles at low densities and strong coupling

Nanocolloids having directional interactions are highly relevant for designing new self-assembled materials easy to control. In this article we report stochastic dynamics simulations of finite-size pseudo-dipolar colloids immersed in an implicit dielectric solvent using a realistic continuous description of the quasi-hard Coulombic interaction. We investigate structural and dynamical properties near the low-temperature and highly-diluted limits. This system self-assembles in a rich variety of string-like configurations, depicting three clearly distinguishable regimes with decreasing temperature: fluid, composed by isolated colloids; string-fluid, a gas of short string-like clusters; and string-gel, a percolated network. By structural characterization using radial distribution functions and cluster properties, we calculate the state diagram, verifying the presence of string-fluid regime. Regarding the string-gel regime, we show that the antiparallel alignment of the network chains arises as a novel self-assembly mechanism when the characteristic interaction energy exceeds the thermal energy in two orders of magnitude, ud/kBT ≈ 100. This is associated to relevant structural modifications in the network connectivity and porosity. Furthermore, our results give insights about the dynamically-arrested nature of the string-gel regime, where we show that the slow relaxation takes place in minuscule energy steps that reflect local rearrangements of the network.Fil: Brito, Mariano Exequiel. Helmholtz Gemeinschaft. Forschungszentrum Jülich; Alemania. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Carignano, Marcelo A.. Qatar Environment And Energy Research Institute; QatarFil: Marconi, Veronica Iris. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentin

Necrosis is the dominant cell death pathway in uropathogenic Escherichia coli elicited epididymo-orchitis and is responsible for damage of rat testis

Male infertility is a frequent medical condition, compromising approximately one in twenty men, with infections of the reproductive tract constituting a major etiological factor. Bacterial epididymo-orchitis results in acute inflammation most often caused by ascending canalicular infections from the urethra via the continuous male excurrent ductal system. Uropathogenic Escherichia coli (UPEC) represent a relevant pathogen in urogenital tract infections. To explore how bacteria can cause damage and cell loss and thus impair fertility, an in vivo epididymo-orchitis model was employed in rats by injecting UPEC strain CFT073 into the vas deference in close proximity to the epididymis. Seven days post infection bacteria were found predominantly in the testicular interstitial space. UPEC infection resulted in severe impairment of spermatogenesis by germ cell loss, damage of testicular somatic cells, a decrease in sperm numbers and a significant increase in TUNEL (+) cells. Activation of caspase-8 (extrinsic apoptotic pathway), caspase-3/−6 (intrinsic apoptotic pathway), caspase-1 (pyroptosis pathway) and the presence of 180 bp DNA fragments, all of which serve as indicators of the classical apoptotic pathway, were not observed in infected testis. Notably, electron microscopical examination revealed degenerative features of Sertoli cells (SC) in UPEC infected testis. Furthermore, the passive release of high mobility group protein B1 (HMGB1), as an indication of necrosis, was observed in vivo in infected testis. Thus, necrosis appears to be the dominant cell death pathway in UPEC infected testis. Substantial necrotic changes seen in Sertoli cells will contribute to impaired spermatogenesis by loss of function in supporting the dependent germ cells

A novel linkage map of sugarcane with evidence for clustering of retrotransposon-based markers

The development of sugarcane as a sustainable crop has unlimited applications. The crop is one of the most economically viable for renewable energy production, and CO2 balance. Linkage maps are valuable tools for understanding genetic and genomic organization, particularly in sugarcane due to its complex polyploid genome of multispecific origins. The overall objective of our study was to construct a novel sugarcane linkage map, compiling AFLP and EST-SSR markers, and to generate data on the distribution of markers anchored to sequences of scIvana_1, a complete sugarcane transposable element, and member of the Copia superfamily. The mapping population parents (‘IAC66-6’ and ‘TUC71-7’) contributed equally to polymorphisms, independent of marker type, and generated markers that were distributed into nearly the same number of co-segregation groups (or CGs). Bi-parentally inherited alleles provided the integration of 19 CGs. The marker number per CG ranged from two to 39. The total map length was 4,843.19 cM, with a marker density of 8.87 cM. Markers were assembled into 92 CGs that ranged in length from 1.14 to 404.72 cM, with an estimated average length of 52.64 cM. The greatest distance between two adjacent markers was 48.25 cM. The scIvana_1-based markers (56) were positioned on 21 CGs, but were not regularly distributed. Interestingly, the distance between adjacent scIvana_1-based markers was less than 5 cM, and was observed on five CGs, suggesting a clustered organization. Results indicated the use of a NBS-profiling technique was efficient to develop retrotransposon-based markers in sugarcane. The simultaneous maximum-likelihood estimates of linkage and linkage phase based strategies confirmed the suitability of its approach to estimate linkage, and construct the linkage map. Interestingly, using our genetic data it was possible to calculate the number of retrotransposon scIvana_1 (~60) copies in the sugarcane genome, confirming previously reported molecular results. In addition, this research possibly will have indirect implications in crop economics e.g., productivity enhancement via QTL studies, as the mapping population parents differ in response to an important fungal disease13CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPnão temnão tem2010/51708-

Formulação de drageados de frutas com solução de reuso da desidratação osmótica de abacaxi

The objective of this work was to evaluate the reuse of sucrose syrup in pineapple (Ananas comosus) osmotic dehydration and the application of the spent solution in fruit dragée formulation. Osmotic dehydration trials were performed in five cycles (65° Brix/45°C/3 hours), directly reusing the osmotic solution, with only one intermediate reconditioning step. Variations in osmotic solution properties and in dehydration parameters were observed, as well as a low microbial load in the system. The spent solution was rich in vitamin C (30 mg 100 g-1). Pineapple dragée covered with red fruits and acai powders were obtained with the reconditioned spent solution used as an adhesion solution. The dragée presented high levels of vitamin C (176 mg 100 g-1), polyphenols (154 mg GAE 100-1 g), carotenoids (220 µg 100 g-1), and potassium (330 mg 100 g-1). The product showed good sensory acceptance and purchase intention. Reusing sucrose syrup is technically feasible during pineapple osmotic dehydration, as is the application of the spent solution as an ingredient in fruit dragée production.O objetivo deste trabalho foi avaliar o reuso do xarope de sacarose na desidratação osmótica de abacaxi (Ananas comosus) e o uso da solução final na formulação de drageados de frutas. Os ensaios de desidratação osmótica foram conduzidos em cinco ciclos (65 °Brix/45°C/3 horas), com reuso direto da solução osmótica, com apenas uma etapa intermediária de recondicionamento. Foram observadas variações nas propriedades da solução osmótica e nos parâmetros da desidratação, bem como baixa carga microbiana do sistema. A solução final apresentou-se rica em vitamina C (30 mg 100 g-1). Foram obtidos drageados de abacaxi cobertos com frutas vermelhas e açaí em pó com a solução final recondicionada como solução de aderência. O drageado apresentou níveis elevados de vitamina C (176 mg 100 g-1), polifenóis (154 mg GAE 100 g-1), carotenoides (220 µg 100 g-1) e potássio (330 mg100 g-1). O produto teve boa aceitação e intenção de compra. O reuso do xarope de sacarose é tecnicamente viável na desidratação osmótica de abacaxi, bem como a aplicação da solução final como ingrediente na produção de drageados de frutas

Revascularização e rejeição do transplante heterotópico de traquéia conservada em glicerina

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Revascularização e rejeição do transplante heterotópico de traquéia conservada em glicerina

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A construção e o caminhar do grupo união agroecológica de inconfidentes: agroecologia como/é resistência/autonomia estudantil

O relato apresentado aborda sobre a construção de um grupo de agroecologia em uma instituição federal de ensino. O grupo foi idealizado por discentes e vem sendo construído pela autonomia e resistência estudantil, autogestionado de maneira horizontal. São inúmeras as atividades desenvolvidas, em parcerias com diversos movimentos sociais, sindicais, estudantis e culturais. A postura tomada pelos discentes do grupo, que deveria ser vista como positiva pelos demais envolvidos e apoiada pela instituição, ocorre de maneira contrária. São poucos os docentes e servidores que apóiam a iniciativa e por parte da instituição não existe apoio algum para a autonomia estudantil, ainda mais quando se diz respeito a uma construção coletiva. O perfil e objetivo do grupo são: jovens que estão buscando conhecimento, através de estudos, pesquisas, extensão e debates nas diversas áreas temáticas da agroecologia que perpetuam questões ambientais e sociais.Eje: B6 Desarrollo rural, movimientos sociales, Estado y agroecología (Relatos de experiencias)Facultad de Ciencias Agrarias y Forestale