Multiscale method for characterization of porous microstructures and their impact on macroscopic effective permeability

Recent technology advancements on X-ray computed tomography (X-ray CT) offer a nondestructive approach to extract complex three-dimensional geometries with details as small as a few microns in size. This new technology opens the door to study the interplay between microscopic properties (e.g. porosity) and macroscopic fluid transport properties (e.g. permeability). To take full advantage of X-ray CT, we introduce a multiscale framework that relates macroscopic fluid transport behavior not only to porosity but also to other important microstructural attributes, such as occluded/connected porosity and geometrical tortuosity, which are extracted using new computational techniques from digital images of porous materials. In particular, we introduce level set methods, and concepts from graph theory, to determine the geometrical tortuosity and connected porosity, while using a lattice Boltzmann/finite element scheme to obtain homogenized effective permeability at specimen-scale. We showcase the applicability and efficiency of this multiscale framework by two examples, one using a synthetic array and another using a sample of natural sandstone with complex pore structure

Particle separation by phase modulated surface acoustic waves

High efficiency isolation of cells or particles from a heterogeneous mixture is a critical processing step in lab-on-a-chip devices. Acoustic techniques offer contactless and label-free manipulation, preserve viability of biological cells, and provide versatility as the applied electrical signal can be adapted to various scenarios. Conventional acoustic separation methods use time-of-flight and achieve separation up to distances of quarter wavelength with limited separation power due to slow gradients in the force. The method proposed here allows separation by half of the wavelength and can be extended by repeating the modulation pattern and can ensure maximum force acting on the particles. In this work, we propose an optimised phase modulation scheme for particle separation in a surface acoustic wave microfluidic device. An expression for the acoustic radiation force arising from the interaction between acoustic waves in the fluid was derived. We demonstrated, for the first time, that the expression of the acoustic radiation force differs in surface acoustic wave and bulk devices, due to the presence of a geometric scaling factor. Two phase modulation schemes are investigated theoretically and experimentally. Theoretical findings were experimentally validated for different mixtures of polystyrene particles confirming that the method offers high selectivity. A Monte-Carlo simulation enabled us to assess performance in real situations, including the effects of particle size variation and non-uniform acoustic field on sorting efficiency and purity, validating the ability to separate particles with high purity and high resolution

The Effect of Confinement on Capillary Phase Transition In Granular Aggregates

Utilizing a 3D mean-field lattice-gas model, we analyze the effect of confinement on the nature of capillary phase transition in granular aggregates with varying disorder and their inverse porous structures obtained by interchanging particles and pores. Surprisingly, the confinement effects are found to be much less pronounced in granular aggregates as opposed to porous structures. We show that this discrepancy can be understood in terms of the surface-surface correlation length with a connected path through the fluid domain, suggesting that this length captures the true degree of confinement. We also find that the liquid-gas phase transition in these porous materials is of second order nature near capillary critical temperature, which is shown to represent a true critical temperature, i.e. independent of the degree of disorder and the nature of solid matrix, discrete or continuous. The critical exponents estimated here from finite-size scaling analysis suggest that this transition belongs to the 3D random field Ising model universality class as hypothesized by P.G. de Gennes, with the underlying random fields induced by local disorder in fluid-solid interactions

Cross-evaluation of the therapeutical methods for idiopathic congenital clubfoot (talipes equinovarus): controversies regarding the tendocalcaneous tenotomy

OBJECTIVE: There has been a lot of discussion regarding the treatment of congenital clubfoot (talipes equinovarus,) and Posenti's methodology currently seems to be the most rational, offering high rates of satisfactory results when compared to Kite's approach that prevailed in orthopedics until the end of the 90s. With the recent change of concepts, this study purports to analyze the profile of orthopedists treating this infirmity in Brazil, through a questionnaire used at the 39th Brazilian Congress of Orthopaedics and Traumatology, since such data is unknown in the Brazilian literature. METHODS: An investigative questionnaire was prepared to ascertain the treatment method used, the characteristics of the population studied, the results acquired with treatment and, particularly, how they approached the Achilles tendon. RESULTS: Of the 5,329 registered orthopedists, we acquired 539 spontaneous participations. Of these, only 88 (16.30%) orthopedists perform the treatment for congenital clubfoot; 78 (88.60%) use the Ponseti method and 9 (10.20%) use Kite's; for 47.70%, conservative treatment is performed between 4 and 6 months and for 35.30%, between 1 and 3 months; 58 (66.00%) interviewees perform the Achilles tendon tenotomy in 80% to 100% of their patients and 59 (67.05%) perform it at a surgical center due to safety conditions, sterilized environment, anesthesia, ease of access, and patient monitoring; 32 (36.36%) orthopedists present 80% of good results or more, 54 (61.36%) present 50% to 80% good results and 46 (52.27%) present a 10% relapse rate. CONCLUSIONS: Although the Ponseti Method defines that the Achilles tendon tenotomy should be performed in an outpatient setting, most of the orthopedists (59 - 67.05%) perform it in the operating room.OBJETIVO: Há muita discussão em relação ao tratamento do pé torto congênito equino-cavo-varo e atualmente a sistemática proposta por Ponseti parece ser a mais racional oferecendo altas taxas de resultados satisfatórios em detrimento à metodologia de Kite que predominou no meio ortopédico até o final da década de 90. Com a recente mudança de conceitos, este trabalho tem o intuito de analisar, por meio de questionário aplicado no 39° Congresso Brasileiro de Ortopedia e Traumatologia, o perfil dos ortopedistas no Brasil frente a esta afecção, fato este desconhecido considerando a literatura nacional. MÉTODO: Um questionário para investigação foi elaborado para verificar o método de tratamento utilizado, as características da população estudada, os resultados obtidos com o tratamento e particularmente como abordam cirurgicamente o tendão calcâneo. RESULTADOS: Do total de 5.329 ortopedistas inscritos, obtivemos 539 participações espontâneas; destes, somente 88 (16,30%) indivíduos executam o tratamento para o pé torto congênito; 78 (88,60%) aplicam o método de Ponseti; e nove (10,20%) o de Kite. Para 47,70%, o tratamento conservador é realizado entre quatro e seis meses e para 35,20% entre um e três meses; 58 (66,00%) entrevistados efetuam a tenotomia do tendão calcâneo em 80% a 100% de seus pacientes e 59 (67,05%) a realizam no centro cirúrgico devido às condições de segurança, assepsia, anestesia, facilidade de acesso e monitorização do paciente; 32 (36,36%) ortopedistas apresentam 80% ou mais de bons resultados, 54 (61,36%) apresentam 50% a 80% de bons resultados e 46 (52,27%) apresentam taxa de recidiva de 10%. CONCLUSÃO: Embora o método de Ponseti defina que a tenotomia do tendão calcâneo seja realizada ambulatorialmente com anestesia local, a maioria 59 (67,05%) dos ortopedistas a realiza no centro cirúrgico.Universidade Federal de São Paulo (UNIFESP) Departamento de Ortopedia e TraumatologiaUniversidade Federal de São Paulo (UNIFESP) Departamento de Ortopedia e Traumatologia Ortopedia PediátricaUNIFESP, Depto. de Ortopedia e TraumatologiaUNIFESP, Depto. de Ortopedia e Traumatologia Ortopedia PediátricaSciEL

The Psychedelic State Induced by Ayahuasca Modulates the Activity and Connectivity of the Default Mode Network

The experiences induced by psychedelics share a wide variety of subjective features, related to the complex changes in perception and cognition induced by this class of drugs. A remarkable increase in introspection is at the core of these altered states of consciousness. Self-oriented mental activity has been consistently linked to the Default Mode Network (DMN), a set of brain regions more active during rest than during the execution of a goal-directed task. Here we used fMRI technique to inspect the DMN during the psychedelic state induced by Ayahuasca in ten experienced subjects. Ayahuasca is a potion traditionally used by Amazonian Amerindians composed by a mixture of compounds that increase monoaminergic transmission. In particular, we examined whether Ayahuasca changes the activity and connectivity of the DMN and the connection between the DMN and the task-positive network (TPN). Ayahuasca caused a significant decrease in activity through most parts of the DMN, including its most consistent hubs: the Posterior Cingulate Cortex (PCC)/Precuneus and the medial Prefrontal Cortex (mPFC). Functional connectivity within the PCC/Precuneus decreased after Ayahuasca intake. No significant change was observed in the DMN-TPN orthogonality. Altogether, our results support the notion that the altered state of consciousness induced by Ayahuasca, like those induced by psilocybin (another serotonergic psychedelic), meditation and sleep, is linked to the modulation of the activity and the connectivity of the DMN.The Brazilian Federal Agencies: CNPq, CAPES; FINEP; The Sao Paulo State financial agency (FAPESP)

GASTRO PROTECTIVE AND ANTI-HELICOBACTER PYLORI EFFECTS OF A FLAVONOID RICH FRACTION OBTAINED FROM ACHYROCLINE SATUREOIDES (LAM) D.C.

Objectives: The study aimed to investigate the gastroprotective effects of a flavonoid rich fraction (FRF) obtained from Achyrocline satureoides. Methods: The following protocols were employed: ethanol and NSAID-induced ulcer, ligature pylorus model, and free mucus quantification. Nitric oxide (NO) and sulfhydryl group participation were observed by pretreatment with L-NAME or NEM. Besides, it was assayed the acetic acid-induced chronic ulcer andthe anti-Helicobacter pyloriactivity in vitro. Results: The phytochemical profile of FRF showed three main flavonoids, luteolin, quercetin and 3-O-methyl-quercetin. The administration of FRF was able to prevent the damage evoked by ethanol and NSAID-induced ulcer models. The pH and concentration of H+ in the stomach were not modified by FRF treatment. However, the FRF treatment induces mucus secretion. The effect presented by FRF was mediated by nitric oxide (NO). In chronic ulcer model FRF reduced significantly the lesion area, promoting a cure ratio of 65.42±13.00, a similar data presented by cimetidine treated animals (61.35±11.88). Using an in vitro assay was observed that FRF at 500 µg/mL was able to inhibit bacterial growth. Conclusions: The results show that FRF provided a significant gastroprotective and ulcer healing activity, mainly due to their capacity to enhance mucus secretion

RIT with Y90-Ibritumomab Tiuxetan in Follicular Non-Hodgkin Lymphoma: Evaluation of Recent Outcomes in a Single Institution

Background. Based on historical data we reviewed our hospital clinical database to analyse our updated information and therapy outcomes of follicular non-Hodgkin lymphoma (F-NHL) patients treated with 90Y-Ibritumomab tiuxetan. Patients and Methods. Between 2005 and 2011, 56 F-NHL patients were included in a clinical protocol conducted by a multidisciplinary team and treated in the same centre. All patients received 0.3 or 0.4 mCi/kg IV (88%) of 90Y-IT; response evaluation was performed 12 weeks after. Results. M/F 44.6%/55.4%, mean age 61.45 years (30–85); ECOG 0-1 96.9%. According to FLIPI score, distribution were good: 58.5%, intermediate: 29.2%, and poor: 12.3%. Previous therapies: >2: 40% (26). ORR was 94.6% (53/56). CR: 85.7%; CR according to previous disease: relapsed disease: 90% (27/30), refractory disease: 42.85% (3/7), consolidation with CR: 92.85% (13/14), and consolidation with PR: 100% (5/5). Global PR and NR were 8.9% (5) and 5.3% (3), respectively. Mean OS 63.86 months with a mean follow-up time of 57 months (2–73). Mean TTP: 52.65 months (95% CI: 43.83–61.48). Median OS and TTP were not achieved. No hospital submissions or deaths were registered. Conclusions. This study confirms the safety and high efficacy of 90Y-IT in F-NHL patients, RIT in early stage of disease could improve outcomes

Evaluation of the effects of Quercetin and Kaempherol on the surface of MT-2 cells visualized by atomic force microscopy

AbstractThis study investigated the anti-viral effects of the polyphenolic compounds Quercetin and Kaempherol on the release of HTLV-1 from the surface of MT-2 cells. Atomic force microscopy (AFM) was used to scan the surface of the MT-2 cells. MT-2 cells were fixed with 100% methanol on round glass lamina or cleaved mica and dried under UV light and laminar flow. The images were captured on a Multimode equipment monitored by a NanoScope IIId controller from Veeco Instruments Inc operated in tapping mode and equipped with phase-imaging hardware. The images demonstrated viral budding structures 131±57nm in size, indicating profuse viral budding. Interestingly, cell-free viruses and budding structures visualized on the surface of cells were less common when MT-2 was incubated with Quercetin, and no particles were seen on the surface of cells incubated with Kaempherol. In summary, these data indicate that HTLV-1 is budding constantly from the MT-2 cell surface and that polyphenolic compounds were able to reduce this viral release. Biological samples were analyzed with crude cell preparations just after cultivation in the presence of Quercetin and Kaempherol, showing that the AFM technique is a rapid and powerful tool for analysis of antiviral activity of new biological compounds

Fractional Distillation of Bio-Oil Produced by Pyrolysis of Açaí (Euterpe oleracea) Seeds

In this work, the seeds of açaí (Euterpe oleracea, Mart), a rich lignin-cellulose residue, has been submitted to pyrolysis to produce a bio-oil-like fossil fuels. The pyrolysis carried out in a reactor of 143 L, 450°C, and 1.0 atm. The morphology of Açaí seeds in nature and after pyrolysis is characterized by SEM, EDX, and XRD. The experiments show that bio-oil, gas, and coke yields were 4.38, 30.56, and 35.67% (wt.), respectively. The bio-oil characterized by AOCS, ASTM, and ABNT/NBR methods for density, kinematic viscosity, and acid value. The bio-oil density, viscosity, and acid value were 1.0468 g/cm3, 68.34 mm2/s, and 70.26 KOH/g, respectively. The chemical composition and chemical functions of bio-oil are determined by GC-MS and FT-IR. The GC-MS identified in bio-oil 21.52% (wt.) hydrocarbons and 78.48% (wt.) oxygenates (4.06% esters, 8.52% carboxylic acids, 3.53% ketones, 35.16% phenols, 20.52% cresols, 5.75% furans, and 0.91% (wt.) aldehydes), making it possible to apply fractional distillation to obtain fossil fuel-like fractions rich in hydrocarbons. The distillation of bio-oil is carried out in a laboratory-scale column, according to the boiling temperature of fossil fuels. The distillation of bio-oil yielded fossil fuel-like fractions (gasoline, kerosene, and light diesel) of 4.70, 28.21, and 22.35% (wt.), respectively

Brazilian urban population genetic structure reveals a high degree of admixture

Advances in genotyping technologies have contributed to a better understanding of human population genetic structure and improved the analysis of association studies. To analyze patterns of human genetic variation in Brazil, we used SNP data from 1129 individuals - 138 from the urban population of Sao Paulo, Brazil, and 991 from 11 populations of the HapMap Project. Principal components analysis was performed on the SNPs common to these populations, to identify the composition and the number of SNPs needed to capture the genetic variation of them. Both admixture and local ancestry inference were performed in individuals of the Brazilian sample. Individuals from the Brazilian sample fell between Europeans, Mexicans, and Africans. Brazilians are suggested to have the highest internal genetic variation of sampled populations. Our results indicate, as expected, that the Brazilian sample analyzed descend from Amerindians, African, and/or European ancestors, but intermarriage between individuals of different ethnic origin had an important role in generating the broad genetic variation observed in the present-day population. The data support the notion that the Brazilian population, due to its high degree of admixture, can provide a valuable resource for strategies aiming at using admixture as a tool for mapping complex traits in humans. European Journal of Human Genetics (2012) 20, 111-116; doi:10.1038/ejhg.2011.144; published online 24 August 2011CNPq (Brazil) [150653/2008-5]FAPESP [2007/58150-7]Hospital Samaritano, Sao Paul