3D printed microchannels for sub-nL NMR spectroscopy

Nuclear magnetic resonance (NMR) experiments on subnanoliter (sub-nL) volumes are hindered by the limited sensitivity of the detector and the difficulties in positioning and holding such small samples in proximity of the detector. In this work, we report on NMR experiments on liquid and biological entities immersed in liquids having volumes down to 100 pL. These measurements are enabled by the fabrication of high spatial resolution 3D printed microfluidic structures, specifically conceived to guide and confine sub-nL samples in the sub-nL most sensitive volume of a single-chip integrated NMR probe. The microfluidic structures are fabricated using a two-photon polymerization 3D printing technique having a resolution better than 1 \u3bcm3. The high spatial resolution 3D printing approach adopted here allows to rapidly fabricate complex microfluidic structures tailored to position, hold, and feed biological samples, with a design that maximizes the NMR signals amplitude and minimizes the static magnetic field inhomogeneities. The layer separating the sample from the microcoil, crucial to exploit the volume of maximum sensitivity of the detector, has a thickness of 10 \u3bcm. To demonstrate the potential of this approach, we report NMR experiments on sub-nL intact biological entities in liquid media, specifically ova of the tardigrade Richtersius coronifer and sections of Caenorhabditis elegans nematodes. We show a sensitivity of 2.5x1013spins/ Hz1/2on1H nuclei at 7 T, sufficient to detect 6 pmol of1H nuclei of endogenous compounds in active volumes down to 100 pL and in a measurement time of 3 hours. Spectral resolutions of 0.01 ppm in liquid samples and of 0.1 ppm in the investigated biological entities are also demonstrated. The obtained results may indicate a route for NMR studies at the single unit level of important biological entities having sub-nL volumes, such as living microscopic organisms and eggs of several mammalians, humans included

Morfoanatomia foliar em mudas de Schinus terebinthifolius sob diferentes níveis de saturação hídrica.

As características morfológicas e anatômicas foliares de espécies vegetais são importantes indicadores de sua ecologia e de seus hábitats. Objetivou-se caracterizar a plasticidade fenotípica de Schinus terebinthifolius Raddi em diferentes condições de saturação hídrica. As mudas foram produzidas em tubetes plásticos, permanecendo em estufa por quatro meses, sendo irrigadas normalmente. Em seguida foram submetidas aos tratamentos: T1- testemunha, T2- alagamento parcial e T3- alagamento total. Após três semanas sob alagamento, foram realizadas descrições anatômicas foliares comparativas e avaliadas as características morfológicas área foliar, área específica foliar, espessura foliar, teor de água e densidade estomática. Durante 10 semanas foram observadas as modificações fenotípicas adaptativas. Foi observado aumento da espessura da base do caule, clorose e abscisão foliar, surgimento de lenticelas e raízes adventícias. Após três semanas de alagamento, não foram verificadas grandes modificações na morfologia das folhas, principalmente para a AF e AEF. Em T3, o teor de água foi maior e a espessura foliar menor. Não houve diferença entre os tratamentos para DE. Quanto aos aspectos anatômicos, observou-se uma redução na espessura do mesofilo e das nervuras, assim como a produção de compostos fenólicos por alguns tipos celulares. Os espaços intercelulares são progressivamente mais amplos nas plantas submetidas ao alagament

Caracterização física e produtividade de acessos de Passiflora nítida no Cerrado do Distrito Federal.

Ref. 71577

On the Fibonacci universality classes in nonlinear fluctuating hydrodynamics

We present a lattice gas model that without fine tuning of parameters is expected to exhibit the so far elusive modified Kardar-Parisi-Zhang (KPZ) universality class. To this end, we review briefly how non-linear fluctuating hydrodynamics in one dimension predicts that all dynamical universality classes in its range of applicability belong to an infinite discrete family which we call Fibonacci family since their dynamical exponents are the Kepler ratios $z_i = F_{i+1}/F_{i}$ of neighbouring Fibonacci numbers $F_i$, including diffusion ($z_2=2$), KPZ ($z_3=3/2$), and the limiting ratio which is the golden mean $z_\infty=(1+\sqrt{5})/2$. Then we revisit the case of two conservation laws to which the modified KPZ model belongs. We also derive criteria on the macroscopic currents to lead to other non-KPZ universality classes.Comment: 17 page

Soil biochemistry and microbial activity in vineyards under conventional and organic management at Northeast Brazil.

The São Francisco Submedium Valley is located at the Brazilian semiarid region and is an important center for irrigated fruit growing. This region is responsible for 97% of the national exportation of table grapes, including seedless grapes. Based on the fact that orgThe São Francisco Submedium Valley is located at the Brazilian semiarid region and is an important center for irrigated fruit growing. This region is responsible for 97% of the national exportation of table grapes, including seedless grapes. Based on the fact that organic fertilization can improve soil quality, we compared the effects of conventional and organic soil management on microbial activity and mycorrhization of seedless grape crops. We measured glomerospores number, most probable number (MPN) of propagules, richness of arbuscular mycorrhizal fungi (AMF) species, AMF root colonization, EE-BRSP production, carbon microbial biomass (C-MB), microbial respiration, fluorescein diacetate hydrolytic activity (FDA) and metabolic coefficient (qCO2). The organic management led to an increase in all variables with the exception of EE-BRSP and qCO2. Mycorrhizal colonization increased from 4.7% in conventional crops to 15.9% in organic crops. Spore number ranged from 4.1 to 12.4 per 50 g-1 soil in both management systems. The most probable number of AMF propagules increased from 79 cm-3 soil in the conventional system to 110 cm-3 soil in the organic system. Microbial carbon, CO2 emission, and FDA activity were increased by 100 to 200% in the organic crop. Thirteen species of AMF were identified, the majority in the organic cultivation system. Acaulospora excavata, Entrophospora infrequens, Glomus sp.3 and Scutellospora sp. were found only in the organically managed crop. S. gregaria was found only in the conventional crop. Organically managed vineyards increased mycorrhization and general soil microbial activity