New physics in the charged relativistic Bose gas using zeta-function regularization?

The multiplicative anomaly, recently introduced in QFT, plays a fundamental role in solving some mathematical inconsistencies of the widely used zeta-function regularization method. Its physical relevance is still an open question and is here analyzed in the light of a non-perturbative method. Even in this approach the ``different physics'' seems to hold and not to be easily removable by renormalization.Comment: 6 pages, LaTeX. Talk given at the ``SEWM2000 - Strong and Electro-Weak Matter 2000''Conference, June 2000, Marseilles, France. Proceedings to be published by World Scientifi

Restos de Allosauroideo (Theropoda, Tetanurae) de la formación sierra barrosa (Coniaciano Medio, Cretácico Superior), Patagonia, Argentina

La fauna de terópodos del Cretácico Tardío de América del Sur está compuesta por Abelisauridae, Noasauridae, Carcharodontosauridae, Spinosauridae, Megaraptora y Coelurosauria. Estos grupos incluyen mayormente taxones de pequeño (Noasauridae y Coelurosauria) y de mediano a gran tamaño (Abelisauridae, Carcharodontosauridae y Megaraptora). Algunos de estos linajes son predominantemente gondwánicos (Abelisauridae, Noasauridae, Carcharodontosauridae, Megaraptora) y poco representados en los continentes laurásicos. Particularmente, distintos terópodos han sido reportados desde la Patagonia, conocidos o por sus distintivas características anatómicas o por su grado de preservación, tales como Carnotaurus, Skorpiovenator, Giganotosaurus, Megaraptor, Alvarezsaurus y Unenlagia. Aquí describimos una nueva tibia incompleta (MAU-PV-CM-653) proveniente de la Formación Sierra Barrosa (Coniaciano medio, Cretácico Superior), Patagonia, Argentina. MAU-PV-CM-653 muestra una cresta cnemial reducida anteroposteriormente, que está fuertemente curvada lateralmente. Finalmente, la tibia carece de una extensión proximal de la cresta fibular. Estos rasgos hacen recordar una morfología de tetanuro y, junto con la procedencia estratigráfica de MAU-PV-CM-653, nos permite asignarla a un terópodo allosauroideo, y por ende mejorar el registro global de Allosauroidea para la parte media del Cretácico Tardío.The late Cretaceous theropod fauna of South America is composed of Abelisauridae, Noasauridae, Spinosauridae, Carcharodontosauridae, Megaraptora, and Coelurosauria. These groups include mostly small (Noasauridae and Coelurosauria) and medium to- tolarge-sized taxa (Carcharodontosauridae, Abelisauridae, and Megaraptora). Some of these lineages are predominantly Gondwanic (Abelisauridae, Noasauridae, Carcharodontosauridae, Megaraptora) and poorly represented in Laurasian landmasses. Particularly, several theropods have been reported from Patagonia, known either due to distinct anatomical features or due to their high degree of preservation, such as Carnotaurus, Skorpiovenator, Giganotosaurus, Megaraptor, Alvarezsaurus, and Unenlagia. here we describe a new incomplete tibia (MAU-PV-CM-653) from the Sierra Barrosa Formation (middle Coniacian, Upper Cretaceous), Patagonia, Argentina. MAU-PV-CM-653 shows an anteroposteriorly reduced cnemial crest that is strongly curved laterally. Finally, the tibia lacks a proximal extension of the fibular crest. These traits are reminiscent of tetanuran morphology and, together with the stratigraphic provenance of MAU-PV-CM-653, they allow us to assign it to an allosauroid theropod, thus improving the Allosauroidea global record for the middle Late Cretaceous.Fil: Baiano, Mattia Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Universidad Nacional de Río Negro; Argentina. Provincia del Neuquén. Municipalidad de Villa El Chocón. Museo Paleontológico "Ernesto Bachmann"; ArgentinaFil: Filippi, Leonardo Sebastián. No especifíca

Structural and functional properties of plant mitochondrial F-ATP synthase

The mitochondrial F-ATP synthase is responsible for coupling the transmembrane proton gradient, generated through the inner membrane by the electron transport chain, to the synthesis of ATP. This enzyme shares a basic architecture with the prokaryotic and chloroplast ones, since it is composed of a catalytic head (F1), located in the mitochondrial matrix, a membrane-bound part (FO), together with a central and a peripheral stalk. In this review we compare the structural and functional properties of F-ATP synthase in plant mitochondria with those of yeast and mammals. We also present the physiological impact of the alteration of F-ATP synthase in plants, with a special regard to its involvement in cytoplasmic male sterility. Furthermore, we show the involvement of this enzyme in plant stress responses. Finally, we discuss the role of F-ATP synthase in shaping the curvature of the mitochondrial inner membrane and in permeability transition pore formation

Caspase-3-like activity and proteasome degradation in grapevine suspension cell cultures undergoing silver-induced programmed cell death

Toxic metal contamination is one of the major environmental concerns of the recent decade, due to the large application of metals in industrial, healthcare and commercial products, even in the form of nanostructures and nanomaterials. Nevertheless, the effects of silver (Ag+) on plants have not yet thoroughly elucidated. Therefore, suspension cell cultures of grapevine were used as a model for investigating silver toxicity. To do this, oxidative stress and programmed cell death (PCD), evaluated as reactive oxygen species production, caspase-3-like activity and ubiquitin-proteasome system, were investigated. As a result, the highest concentration (10 \u3bcM) of Ag+ caused a rapid (within 24 h) induction of PCD (approx. 80%), accompanied by generation of reactive oxygen species and activation of caspase-3-like activity. In the presence of specific inhibitor of this enzyme, a partial recovery of cell viability and a strong inhibition of caspase- 3-like activity was observed. In addition, silver-induced PCD was accompanied either by increase of poly-ubiquitin conjugated proteins and degradation of subunit PBA1 of the proteasome 20S core, similarly to what found for metal-induced neurotoxicity in animals. The present study shows that silver could induce PCD in grapevine suspension cell cultures, mediated by caspase-3-like activity and oxidative stress. These effects were associated to accumulation of poly-ubiquitin conjugated proteins, suggesting the impairment of ubiquitin-proteasome complex, confirmed by the decrease of the PBA1 subunit. These findings indicate that animal and plant cells could share a common pathway in response to toxic metal, which involves PCD and disassembling of proteasome complex

Urban Freight Transport Demand Modelling: a State of the Art

The paper provides a review of freight transport demand models for applications in urban and metropolitan areas. The perspective adopted is the short-term one of public decision-makers involved in transport planning and traffic management. The paper recalls the general methodology to be used for assessing the city logistics scenario and the features of models in relation to the planning horizons: strategic, tactical and operative. The focus is on the transport demand models able to support the assessment of short-term policies/measures. Several models and methods have been proposed. They usually refer to the multi-stage modelling approach and can be classified in terms of reference unit: truck/vehicle, commodity/quantity, delivery and mixed. The paper offers an analysis of pros and cons of each above classes of models. The research prospects are also identified

Effect of internal surface curvature on steady axisymmetric shock waves

A dissertation submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science in Engineering, 2017.The cardinal aspects of supersonic and hypersonic propulsion intake design involve understanding the internal shock wave structures forming therein. A study was conducted to explore the effects of internal surface curvature and entry deflection angle on steady axisymmetric shock waves. Very little is known about these influences with only Curved Shock Theory, produced by M¨ older, providing analytical insight directly after a curved shock wave. The shock waves and accompanying flow fields which were generated were studied via experimental and numerical means. Radius normalised internal radii of curvature of 1, 1.5 and 2 with entry deflection angles of 0◦, 4◦ and 8◦ were investigated between a Mach number range of Mach 2.4 and 3.6. Experimental results were produced using a blow down supersonic wind tunnel facility and were captured via shadowgraph and schlieren flow visualisation techniques. The numerical simulations were validated using the experimental results. A self similar curved shock wave shape equation was presented with an empirical model which uses flow Mach number and internal radius of curvature in order to produce the resulting curved shock shape. Curved Shock Theory streamlines were used to try predict the internal surfaces that produced the curved shocks but results did not correlate. This was due to extreme streamline curvature curving the streamlines when the shock angle approached the Mach angle. Very good agreement was however found between the theoretical and numerical streamlines at lower curvatures. The higher the internal surface curvature and entry deflection angle, the greater the flow fields were impacted. Steeper characteristics formed as a result, curving the shock wave more noticeably. Both the internal surface curvature and entry deflection angle were found to have an effect on the trailing edge expansion fans which then altered the shape of downstream shock wave structures. The highest curvature models produced steady double reflection patterns due the flow being turned in onto itself by the imposed internal surface curvature. The effects of conical and curved internal surfaces were explored for additional insight into the presence of flow-normal curvature and the curving of the attached shock waves.XL201