New freshwater sponges from Amazonian waters

Four species of freshwater sponges have their first register of occurrence for Amazonian waters upon specimens collected from Culuene and Sete de Setembro Rivers (Xingú basin), Tapirapés River (Araguaia basin) and Cuieiras River. Trochospongilla pennsylvanica (POTTS 1882) and Trochospongilla variabilis BONETTO & EZCURRA DE DRAGO (1973) occurred as minute specimens inside large sponges of the genus Metania GRAY (1867) or of the genus Drulia GRAY (1867). T. pennsylvanica has its first register of occurrence for the Neotropical region. Spongilla spoliata n. sp. resembles Spongilla inarmata ANNADALE (1918) and Spongilla aspinosa POTTS (1880) but is readily separated from these two species on account of the characteristic spines on its microscleres. Radiospongilla amazonensis n. sp. differs from its congeners by the particular characteristics of its megascleres and gemmoscleres

Rydberg states of hydrogen-like ions in braneworld

It has been argued that precise measurements of optical transition frequencies between Rydberg states of hydrogen-like ions could be used to obtain an improved value of the Rydberg constant and even to test Quantum Electrodynamics (QED) theory more accurately, by avoiding the uncertainties about the proton radius. Motivated by this perspective, we investigate the influence of the gravitational interaction on the energy levels of Hydrogen-like ions in Rydberg states within the context of the braneworld models. As it is known, in this scenario, the gravitational interaction is amplified in short distances. We show that, for Rydberg states, the main contribution for the gravitational potential energy does not come from the rest energy concentrated on the nucleus but from the energy of the electromagnetic field created by its electrical charge, which is spread in space. The reason is connected to the fact that, when the ion is in a Rydberg state with high angular momentum, the gravitational potential energy is not computable in zero-width brane approximation due to the gravitational influence of the electrovacuum in which the lepton is moving. Considering a thick brane scenario, we calculate the gravitational potential energy associated to the nucleus charge in terms of the confinement parameter of the electric field in the brane. We show that the gravitational effects on the energy levels of a Rydberg state can be amplified by the extra dimensions even when the compactification scale of the hidden dimensions is shorter than the Bohr radius

The Electron Temperature Gradient in the Galactic Disk

We derive the electron temperature gradient in the Galactic disk using a sample of HII regions that spans Galactocentric distances 0--17 kpc. The electron temperature was calculated using high precision radio recombination line and continuum observations for more than 100 HII regions. Nebular Galactocentric distances were calculated in a consistent manner using the radial velocities measured by our radio recombination line survey. The large number of nebulae widely distributed over the Galactic disk together with the uniformity of our data provide a secure estimate of the present electron temperature gradient in the Milky Way. Because metals are the main coolants in the photoionized gas, the electron temperature along the Galactic disk should be directly related to the distribution of heavy elements in the Milky Way. Our best estimate of the electron temperature gradient is derived from a sample of 76 sources for which we have the highest quality data. The present gradient in electron temperature has a minimum at the Galactic Center and rises at a rate of 287 +/- 46 K/kpc. There are no significant variations in the value of the gradient as a function of Galactocentric radius or azimuth. The scatter we find in the HII region electron temperatures at a given Galactocentric radius is not due to observational error, but rather to intrinsic fluctuations in these temperatures which are almost certainly due to fluctuations in the nebular heavy element abundances. Comparing the HII region gradient with the much steeper gradient found for planetary nebulae suggests that the electron temperature gradient evolves with time, becoming flatter as a consequence of the chemical evolution of the Milky Way's disk.Comment: 43 pages, 9 figures (accepted for publication in the ApJ

Ethics and Design in the Brazilian Context

Often driven by practical and immediate requirements, more and more people are incorporating technology into a variety of aspects of their lives, often without reflecting on the consequences of using them. On the other hand, studies on interactive system development that lead to behavioral change have been gaining ground on the agenda of large HCI conferences. This movement brings to the forefront the fundamental issues of ethics in design and technology use. A designer’s intentions, when directing certain actions or behaviors, are not always explicit or desired by the stakeholders affected by the use of the technology. Systems that induce an undesired purchase, or even those that use conditioning strategies to cause a behavioral change are examples of such intentions. The challenge proposed is therefore about the relationship between design and personal freedom in a way that these technology users do not become victims, either passively or submissively, of the effects of its use. This advance allows for the redefinition of the relationship between man and technology, and the application of new forms of designing and developing interactive systems that take into account the ethical aspects of this relationship

Drying of α-amylase by spray drying and freeze-drying - a comparative study

This study is aimed at comparing two traditional methods of drying of enzymes and at verifying the efficiency of each one and their advantages and disadvantages. The experiments were performed with a laboratory spray dryer and freeze-dryer using α-amylase as the model enzyme. An experimental design in star revealed that spray drying is mainly influenced by the inlet air temperature and feed flow rate, which were considered to be the main factors influencing the enzymatic activity and water activity; the long period of material exposure to high temperatures causes a partial activity loss. In the experiments of freeze drying, three methods of freezing were used (freezer, acetone and dry ice, and liquid nitrogen) and samples subsequently freeze-dried for times ranging between 0-24 hours. The product obtained from the two techniques showed high enzymatic activity and low water activity. For the drying of heat-resistant enzymes, in which the product to be obtained does not have high added value, spray drying may be more economically viable because, in the freeze drying process, the process time can be considered as a limiting factor when choosing a technique313625631FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP99/12379-5; 01/00571-

Viable entanglement detection of unknown mixed states in low dimensions

We explore procedures to detect entanglement of unknown mixed states, which can be experimentally viable. The heart of the method is a hierarchy of simple feasibility problems, which provides sufficient conditions to entanglement. Our numerical investigations indicate that the entanglement is detected with a cost which is much lower than full state tomography. The procedure is applicable to both free and bound entanglement, and involves only single copy measurements.Comment: 8 pages, 9 figures, 4 table

Modeling electrodialysis and a photochemical process for their integration in saline wastewater treatment.

Oxidation processes can be used to treat industrial wastewater containing non-biodegradable organic compounds. However, the presence of dissolved salts may inhibit or retard the treatment process. In this study, wastewater desalination by electrodialysis (ED) associated with an advanced oxidation process (photo-Fenton) was applied to an aqueous NaCl solution containing phenol. The influence of process variables on the demineralization factor was investigated for ED in pilot scale and a correlation was obtained between the phenol, salt and water fluxes with the driving force. The oxidation process was investigated in a laboratory batch reactor and a model based on artificial neural networks was developed by fitting the experimental data describing the reaction rate as a function of the input variables. With the experimental parameters of both processes, a dynamic model was developed for ED and a continuous model, using a plug flow reactor approach, for the oxidation process. Finally, the hybrid model simulation could validate different scenarios of the integrated system and can be used for process optimization