Biodegradability of diesel and biodiesel blends

The biodegradability of pure diesel and biodiesel and blends with different proportions of biodiesel (2%(commercial); 5% and 20%) was evaluated employing the respirometric method and the redox indicator2,6-dichlorophenol indophenol (DCPIP) test. In the former, experiments simulating the contamination of natural environments (soil from a petrol station or water from a river) were carried out in Bartha biometer flasks (250 ml), and used to measure the microbial CO2 production. With the DCPIP test, the capability of three inocula to biodegrade the blends was tested. Results show that although biodiesel is more easily and faster biodegraded than diesel oil, among the blends evaluated (2%, 5% and 20%), only the blend with higher concentration of biodiesel presented biodegradability significantly different from diesel and it was not verified an improvement on the biodegradation of the diesel by means of  cometabolism

Surgical resection of a giant peripheral ossifying fibroma in mouth floor managed with fiberscopic intubation

Tracheal intubation for general anesthesia can sometimes be difficult in patients with a large mass in the mouth floor. Preoperative evaluation of the patient's airway is most important when treating large oral disease

Aerobic biodegradation of butanol and diesel oil blends

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)This work aimed to evaluate the aerobic biodegradation of butanol/diesel oil blends (5, 10, 15, 20%, v/v) in comparison to the biodiesel/diesel oil blend (20%, v/v). Respirometric experiments simulating the contamination of natural environments (soil and water from a river) were carried out in biometer flasks (250 mL) used to measure microbial carbon dioxide (CO(2)) production. The automated turbidimeter Bioscreen C was used to follow the growth of Pseudomonas aeruginosa LBI on butanol/diesel oil blends. A redox indicator (2,6-dichlorophenol indophenol - DCPIP) test was used to evaluate the capability of four inocula to biodegrade the blends with 20% (v/v). The experiment which simulated the soil contamination demonstrated that butanol is less biodegradable than diesel oil, and for this reason the increase in the portion of butanol in the butanol/diesel blend from 5 to 20% had negative effects on biodegradation. While in soil the biodiesel/diesel blend was more easily biodegraded than the butanol/diesel blend, in water this order was the inverse. The insoluble fuels (diesel and biodiesel) were poorly biodegraded in water and the biodegradation of the butanol/diesel blend was favored by the water solubilization of the butanol, which enhances the bioavailability of this compound. On the other hand, initial concentrations of butanol in the water higher than 10 mL L(-1) inhibited the cell growth of the tested microorganisms. Thus, butanol toxicity presumably had a significant effect on the degree of biodegradation of the fuel blends.94270947101Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Agencia Nacional do Petroleo, Gas Natural e Biocombustiveis (ANP) [PRH-05]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)FAPESP [2007/00341-1, 2007/07049-4]Agencia Nacional do Petroleo, Gas Natural e Biocombustiveis (ANP) [PRH-05

Quantum Fluctuations and the Unruh Effect in Strongly-Coupled Conformal Field Theories

Through the AdS/CFT correspondence, we study a uniformly accelerated quark in the vacuum of strongly-coupled conformal field theories in various dimensions, and determine the resulting stochastic fluctuations of the quark trajectory. From the perspective of an inertial observer, these are quantum fluctuations induced by the gluonic radiation emitted by the accelerated quark. From the point of view of the quark itself, they originate from the thermal medium predicted by the Unruh effect. We scrutinize the relation between these two descriptions in the gravity side of the correspondence, and show in particular that upon transforming the conformal field theory from Rindler space to the open Einstein universe, the acceleration horizon disappears from the boundary theory but is preserved in the bulk. This transformation allows us to directly connect our calculation of radiation-induced fluctuations in vacuum with the analysis by de Boer et al. of the Brownian motion of a quark that is on average static within a thermal medium. Combining this same bulk transformation with previous results of Emparan, we are also able to compute the stress-energy tensor of the Unruh thermal medium.Comment: 1+31 pages; v2: reference adde

Occurrence of B chromosomes in Tetragonisca Latreille, 1811 (Hymenoptera, Apidae, Meliponini): A new contribution to the cytotaxonomy of the genus

Tetragonisca angustula and Tetragonisca fiebrigi have recently been listed as valid species. This study aimed to cytogenetically investigate both species, emphasizing the new registry of B chromosomes in the tribe Meliponini. We analyzed colonies of T. angustula and T. fiebrigi collected at Tangará da Serra, Mato Grosso, Brazil, through conventional Giemsa staining, C-banding, and base-specific fluorochrome staining (CMA3/DAPI). T. angustula showed 2n = 34 chromosomes in females and n = 17 in males, with karyotype formula 2K = 34AM. T. fiebrigi showed numeric variation, with chromosome number varying from 2n = 34 to 2n = 36 in females and from n = 17 to n = 18 in males, with karyotype formula 2K = 32AM+2AMc and 2K = 32AM+2AMc + 1 or 2 B-chromosomes. The B chromosomes are heterochromatic. In T. fiebrigi, the CMA3/DAPI staining revealed four chromosomes with a CMA3 positive band. All individuals from the same colony showed the same number of B chromosomes. T. angustula and T. fiebrigi showed karyotype divergence, principally due to the presence of B chromosomes, which are found only in T. fiebrigi. Our data corroborate the status of valid species for both T. angustula and T. fiebrigi, as recently proposed

DNA Barcoding Identifies Argentine Fishes from Marine and Brackish Waters

DNA barcoding has been advanced as a promising tool to aid species identification and discovery through the use of short, standardized gene targets. Despite extensive taxonomic studies, for a variety of reasons the identification of fishes can be problematic, even for experts. DNA barcoding is proving to be a useful tool in this context. However, its broad application is impeded by the need to construct a comprehensive reference sequence library for all fish species. Here, we make a regional contribution to this grand challenge by calibrating the species discrimination efficiency of barcoding among 125 Argentine fish species, representing nearly one third of the known fauna, and examine the utility of these data to address several key taxonomic uncertainties pertaining to species in this region..This study constitutes a significant contribution to the global barcode reference sequence library for fishes and demonstrates the utility of barcoding for regional species identification. As an independent assessment of alpha taxonomy, barcodes provide robust support for most morphologically based taxon concepts and also highlight key areas of taxonomic uncertainty worthy of reappraisal

On the universality of thermodynamics and η/s ratio for the charged Lovelock black branes

Abstract: We investigate general features of charged Lovelock black branes by giving a detailed description of geometrical, thermodynamic and holographic properties of charged Gauss-Bonnet (GB) black branes in five dimensions. We show that when expressed in terms of effective physical parameters, the thermodynamic behaviour of charged GB black branes is completely indistinguishable from that of charged Einstein black branes. Moreover, the extremal, near-horizon limit of the two classes of branes is exactly the same as they allow for the same AdS2 × R3, near-horizon, exact solution. This implies that, although in the UV the associated dual QFTs are different, they flow in the IR to the same fixed point. The calculation of the shear viscosity to entropy ratio η/s confirms these results. Despite the GB dual plasma has in general a non-universal temperature-dependent η/s, it flows monotonically to the universal value 1/4π in the IR. For negative (positive) GB coupling constant, η/s is an increasing (decreasing) function of the temperature and the flow respects (violates) the KSS bound

On the Evolution of Hexose Transporters in Kinetoplastid Potozoans

Glucose, an almost universally used energy and carbon source, is processed through several well-known metabolic pathways, primarily glycolysis. Glucose uptake is considered to be the first step in glycolysis. In kinetoplastids, a protozoan group that includes relevant human pathogens, the importance of glucose uptake in different phases of the life cycles is well established, and hexose transporters have been proposed as targets for therapeutic drugs. However, little is known about the evolutionary history of these hexose transporters. Hexose transporters contain an intracellular N- and C- termini, and 12 transmembrane spans connected by alternate intracellular and extracellular loops. In the present work we tested the hypothesis that the evolutionary rate of the transmembrane span is different from that of the whole sequence and that it is possible to define evolutionary units inside the sequence. The phylogeny of whole molecules was compared to that of their transmembrane spans and the loops connecting the transmembrane spans. We show that the evolutionary units in these proteins primarily consist of clustered rather than individual transmembrane spans. These analyses demonstrate that there are evolutionary constraints on the organization of these proteins; more specifically, the order of the transmembrane spans along the protein is highly conserved. Finally, we defined a signature sequence for the identification of kinetoplastid hexose transporters

The Chemotherapeutic Drug 5-Fluorouracil Promotes PKR-Mediated Apoptosis in a p53- Independent Manner in Colon and Breast Cancer Cells

The chemotherapeutic drug 5-FU is widely used in the treatment of a range of cancers, but resistance to the drug remains a major clinical problem. Since defects in the mediators of apoptosis may account for chemo-resistance, the identification of new targets involved in 5-FU-induced apoptosis is of main clinical interest. We have identified the ds-RNA-dependent protein kinase (PKR) as a key molecular target of 5-FU involved in apoptosis induction in human colon and breast cancer cell lines. PKR distribution and activation, apoptosis induction and cytotoxic effects were analyzed during 5-FU and 5-FU/IFNα treatment in several colon and breast cancer cell lines with different p53 status. PKR protein was activated by 5-FU treatment in a p53-independent manner, inducing phosphorylation of the protein synthesis translation initiation factor eIF-2α and cell death by apoptosis. Furthermore, PKR interference promoted a decreased response to 5-FU treatment and those cells were not affected by the synergistic antitumor activity of 5-FU/IFNα combination. These results, taken together, provide evidence that PKR is a key molecular target of 5-FU with potential relevance in the clinical use of this drug