Charles Darwin y las glaciaciones más antiguas de Patagonia: los bloques erráticos del alto valle del Río Santa Cruz

Although the depositational environment assigned by Darwin to the large erratic blocks and gravels in the Río Santa Cruz valley has been reinterpreted, his geomorphological and stratigraphic observations are still in force. The large erratic blocks he described as crowning the Condor Cliff terrace and spread at the bottom of the valley just east of this locality (Sites 2 and 3), are now interpreted as indicators of the maximum glacial expansion in Patagonia. Similar blocks, though of a different lithology, accumulated over a lower terrace located up-valley (Site 4), are now linked to moraines and glacifluvial terraces of the Penultimate Glaciation. Finally, in addition to the erratic block discovered by Darwin in the lower Río Santa Cruz valley (Site 1), there are others - recently discovered - which probably account for a catastrophic event ascribed to a big glacier-lake outburst during the last interglacial.No obstante haber sido reinterpretado el ambiente depositacional asignado por Darwin a los grandes bloques erráticos y rodados del valle del río Santa Cruz, siguen vigentes sus observaciones geomorfológicas y estratigráficas. Los grandes bloques erráticos que describe coronando la terraza de Condor Cliff y dispersos en el fondo del valle inmediatamente al este de esta localidad (Sitios 2 y 3), son interpretados ahora como indicadores de la máxima expansión glaciaria de la Patagonia. Bloques similares, aunque de dispar litología, acumulados sobre una terraza más baja situada río arriba (Sitio 4), se vinculan actualmente a morenas y terrazas glacifluviales de la Penúltima Glaciación. Finalmente, al bloque errático descubierto por Darwin en el tramo inferior del valle del río Santa Cruz (Sitio 1), se le suman otros -de reciente descubrimiento- que probablemente den cuenta de un evento catastrófico atribuible al vaciamiento de un gran lago glaciar durante el último interglaciar.Fil: Malagnino, Eduardo Cayetano. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Strelin, Jorge Adrián. Universidad Nacional de Córdoba; Argentin

Characterization of OATP1B3-1B7 (LST-3TM12) - a novel transporter of the OATP1B family

The effectiveness of a drug is determined by its pharmacodynamic and pharmacokinetic properties. While pharmacodynamics describes the interaction between the target structure and the drug, pharmacokinetics is an umbrella term for all the processes influencing the entry of a drug into the organism and eventually its elimination from the organism. An important mechanism that affects the pharmacokinetics of a drug is its transport across membranes by uptake and efflux transporters. Two uptake transporters that have been extensively studied for their impact on pharmacokinetics are OATP1B3 and OATP1B1. These two transporters are encoded on chromosome 12 by the genes SLCO1B3 and SLCO1B1, respectively. Between these genes lies another gene locus annotated as SLCO1B7. This gene is deemed to be a pseudogene as no function has been reported for its translational product. In 2005, an mRNA sequence named LST-3TM12 that is highly similar to SLCO1B7 was submitted to the National Center of Biotechnology (NCBI) by Mizutamari, H. and Abe, T. (NCBI#, AY257470). The aim of this thesis was to assess the function and transcriptional regulation of this mRNA. By aligning the transcripts of SLCO1B3, SLCO1B7, and LST-3TM12, we could show that the initial five exons of LST-3TM12 originate from SLCO1B3 and the remaining part of LST-3TM12 is encoded by SLCO1B7. Due to this finding, LST-3TM12 is referred to as OATP1B3-1B7 in this thesis. Because the OATP1B3-1B7 mRNA and OATP1B3 have the same 5’UTR it seemed likely that they share the same promoter, which was corroborated by our finding that silencing the exon 4 of SLCO1B3 significantly inhibited OATP1B3-1B7 mRNA transcription. Given that the gene SLCO1B3 is controlled by, among others, farnesoid X receptor (FXR), we tested and confirmed that FXR also regulates OATP1B3-1B7 transcription. Hence, OATP1B3-1B7 is part of the FXR regulated gene-network. Our functional assessments of OATP1B3-1B7 revealed that OATP1B3-1B7 transports exogenous and endogenous compounds. Endogenous substances were dehydroepiandrosterone sulfate (DHEAS), estradiol β-D-glucuronide (E2G), taurocholic acid (TCA), and lithocholic acid (LCA). Exogenous substances were the drugs ezetimibe and atorvastatin. Real-time PCR assessment of OATP1B3-1B7 mRNA showed that it is highly expressed in the liver and, to a lesser extent, in the small intestine. Consequently, the protein OATP1B3-1B7 is detectable in the liver and intestine. Strikingly, the cellular location of OATP1B3-1B7 is not sinusoidal, as is the case for OATP1B1 and OATP1B3, but it is located in the smooth endoplasmic reticulum (SER). Given that OATP1B3-1B7 has a broad substrate range and is expressed in tissues dedicated to metabolism, we hypothesized that OATP1B3-1B7 could have a function related to the high metabolic activity of these tissues. One enzyme class that is highly expressed in such tissues are uridine 5'-diphospho-glucuronosyltransferases (UGTs). UGTs are anchored in the SER membrane and have their active enzymatic site facing the SER lumen. However, it is still not clearly understood how UGT substrates reach and leave the active enzymatic site. As OATP1B3-1B7 is a SER transporter, we assessed whether it could provide access to or exit from the lumen and thus contribute to the metabolic activity of the UGTs. We have investigated this hypothesis with regard to ezetimibe, which is a substrate of OATP1B3-1B7 and is highly metabolized by UGTs. In this case, we were able to show that inhibition of OATP1B3-1B7 lowers the glucuronidation rate of ezetimibe. Hence, we propose that OATP1B3-1B7 is a drug transporter that is a gateway for the SER lumen

The Impact of Tobacco Smoking on Oral Health - An Ob-servational Study

Cigarette smoking is a major cause of a high number of diseases including oral diseases. The aim of the present study was to evaluate the impact of smoking on oral health. This is an observational study. In the present research were taken into consideration 200 young adults with an age range of 18 to 25 years old, of which 58% were males and 42% were females. The study found a strong correlation between smoking and very bad gingival status (P= .001; 95% CI 0.42-0.53), missing teeth (P= .001; 95% CI 0.35-0.45), dental caries (P= .001; 95% CI 0.36-0.43), and inflammation of the lips (P= .001; 95% CI 0.33-0.57)

Life safety assessment in multi-storey building fires

Life safety is one of the most important objectives of Performance Based Fire-Design and is commonly considered to be achieved if building occupants escape the effects of the fire unharmed. Numerical simulations are often used to predict fire dynamics and factors affecting the evacuation capabilities of occupants. The main scope of this research is to assess life safety in a multi-storey building fire. Statistics based fire risk assessment is used to choose the scenario to be simulated taking into consideration the damage severity and likelihood of occurrence. In the fire simulations, particular attention is given to the fuel modelling to consider the toxicity of combustion products and thus, its effects on the building occupants. Fire simulations results are then integrated with evacuation simulations. The fire risk assessment and fire/evacuation simulations are performed for a multi-storey hotel building located in Lecce, Italy

An all-densities pedestrian simulator based on a dynamic evaluation of the interpersonal distances

In this paper we deal with pedestrian modeling, aiming at simulating crowd behavior in normal and emergency scenarios, including highly congested mass events. We are specifically concerned with a new agent-based, continuous-in-space, discrete-in-time, nondifferential model, where pedestrians have finite size and are compressible to a certain extent. The model also takes into account the pushing behavior appearing at extreme high densities. The main novelty is that pedestrians are not assumed to generate any kind of "field" in the space around which determines the behavior of the crowd. Instead, the behavior of each pedestrian solely relies on its knowledge of the environment and the evaluation of interpersonal distances between it and the others. The model is able to reproduce the concave/concave fundamental diagram with a "double hump" (i.e. with a second peak) which shows up when body forces come into play. We present several numerical tests (some of them being inspired by the recent ISO 20414 standard), which show how the model can reproduce classical self-organizing patterns

Energy Systems Optimization on Agricultural Sector

Come molti altri settori produttivi, anche l'agricoltura deve affrontare una crescente dipendenza energetica da elettricità, petrolio e gas naturale. Tuttavia, l'agricoltura può rispondere direttamente a tali richieste ricorrendo alle fonti di energia rinnovabili (FER), come il solare fotovoltaico (PV) e gli impianti biogas/biometano (BP). Questi sistemi sono stati fortemente incentivati in passato. Gli attuali sistemi d’incentivazione prevedono invece sussidi commisurati alle caratteristiche aziendali come stalle, fienili, disponibilità di biomasse, ecc. Per questi motivi, per quanto riguarda il settore FV, è necessario utilizzare modelli analitici affidabili per valutare l’orientamento e la tecnologia migliore, in particolare per generatori integrati architettonicamente. Per la produzione di biometano, gli impianti di piccole dimensioni risultano quelli maggiormente incentivati previa alimentazione con sottoprodotti agro-industriali. Tuttavia, le loro performance dipendono fortemente dalla tecnologia d’upgrading. Pertanto, le prospettive economiche offerte da questi sistemi RES sono legate alla scelta della tecnologia da impiegare e non più esclusivamente al semplice dimensionamento. Su questa base, l'obiettivo principale di questo lavoro è stato lo sviluppo di strumenti di supporto decisionali (DSSS) per l'ottimizzazione energetica d’impianti FV e BP. Un primo studio si è focalizzato sull’analisi prestazionale per singolo componente e globale d’impianti FV installati in un’azienda agricola. Inoltre, una procedura analitica di ottimizzazione dei parametri d’impianto è stata definita per massimizzare il rendimento elettrico di un generatore integrato architettonicamente rispetto ad un’installazione a terra. Attraverso una serie d’informazioni tecnico-economiche di tecnologie di upgrading, un secondo studio è stato condotto con l'obiettivo di sviluppare un DSS per valutare la marginalità sul reddito aziendale data dall’installazione on-farm di un impianto BP collegato alla rete del gas naturale. I risultati dei due studi hanno dimostrato come questi DSS possono essere utili strumenti per valutare preventivamente le diverse potenzialità offerte da impianti FV e BP in base alle caratteristiche di un’azienda agricola.Like many other productive sectors, even agriculture must tackle an increasing energy dependency on electricity, petroleum and natural gas. Nevertheless, agriculture can directly respond to such request thanks to renewable energy systems (RES) like solar photovoltaic (PV) and biogas/biomethane (BP) plants. These systems have been strongly incentivized in the past. On the contrary, current incentive schemes provide feed-in-tariffs proportionate to farming characteristics as stables, barns, biomass availability, etc. For this reason, as regards the PV sector, it is required to use reliable analytical models for assessing the best orientation and technology, in particular for architecturally integrated generators. For the biomethane production, small-medium plants have stronger incentives in particular using agro-food by-products as feed. However, their performances are strongly dependent on biomethane upgrading technology. Thus, the economic prospective offered by these RES systems are substantially tied to technology choice optimization and no longer solely in simple sizing. On this basis, the main goal of this work is to develop Decision Support Tools (DSSs) for energy optimization both for PV and BP plants. A first study was focused on the analysis of PV plants installed in the same farm. The aim is to examine the impact each plant component has on the PV generator global efficiency and define an analytical procedure for technical parameters optimization in order to maximize the electric yield of an architectonically integrated plant compared to a ground-mounted one. Based on the economic and efficiency features of a biomethane upgrading technology set, a second study was carried out with the aim to design a DSS to assess enterprise-wide profit margins resulting from the on-farm BP plant installation linked to the natural gas grid. The results of the two studies have shown how these DSSs can be useful tools for choosing PV and BP technologies based on farm characteristics

Influence of Rotation Speed of Mtwo Files on Root Canal Instrumentation Time with Different Canal Curvatures

Introduction: The aim of this study was to analyze the effect of rotation speed on the instrumentation time of root canals with different curvatures using Mtwo NiTi rotary instruments. Methods and Materials: Forty root canals were selected and divided into 2 groups, according to the angle of curvature (group A>30°, group B<30°). Both groups were divided into 2 subgroups (n=10), according to the rotational speed used for root canal instrumentation (150 rpm: group A1 and B1; 250 rpm: group A2 and B2). The total instrumentation time and the total number of instrumentation cycles (NCI) required to complete root canal preparation were registered for each canal. The mean and standard deviation were then calculated. Data were then statistically analyzed using two-way ANOVA and interaction effect P-values (P<0.05). Results: During root canal instrumentation, there were no file fractures. Total instrumentation time of the low speed groups A1 (150 rpm) and B1 (150 rpm) were significantly higher (P<0.05) than that of the high speed groups, A2 (250 rpm) and B2 (250 rpm); however, there was no statistically significant difference in terms of NCI between the different groups (P>0.05). Statistical difference was not found between the different angles of curvature, group A1 vs B1 and A2 vs B2 in terms of total instrumentation time (P>0.05) and NCI (P>0.05). Conclusions: This ex-vivo study showed that canal preparation with Mtwo rotary files could be completed safely with an increase of the instrumentation time at low rotational speed independently of the root canal curvature

Colloidal suspensions in external rotating electric field: experimental studies and prospective applications in physics, material science, and biomedicine

Colloidal suspensions and tunable self-assembly of colloidal particles attract a great interest in recent years. In this paper, we propose a new setup and technology for studies of self-assembly of colloidal particles, interection of which between themselves is tuned by external rotating electric fields. We reveal wide prospectives of electric field employment for tunable self-assembly, from suspensions of inorganic particles to ensembles of biological cells. These results make enable particle-resolved studies of various collective phenomena and fundamental processes in many-particle systems in equilibrium state and far from it, while the dynamics can be resolved at the level of individual particles using video microscopy. For the first time, we demonstrate that, apart from ability to prepare photonic crystalline films of inorganic silica particles, the tunable self-assembly provides a novel technological way for manipulation with ensembles of biological cells by control of interactions between them

Conditioning of root canal anatomy on static and dynamics of nickel-titanium rotary instruments

Abstract Aim Aim of this study is to analyze the real movement, influenced by anatomical difficulties, of nickel-titanium rotary instruments within root canal systems; then the objective is to point out the physical and geometrical characteristics of an ideal instrument, able to overcome the most complex anatomies. Methodology At first, observation of the behavior of nickel-titanium rotary instruments within root canal systems and of the influence on them of root canal anatomy. Then, attempt to avoid the anatomical obstructions exploiting, with manual rotation, the advantages of a zero/low torque. Results Given that, in some root canals the severity of the curves prevents instruments to advance in rotation, we obtained significant results by manually advancing and rotating NiTi rotary instruments. Conclusions Therefore, in some cases, we would need an instrument that can reconcile efficiency with a reduction of mass and torque; the ideal instrument should have a very contained working part, combining efficiency with the decrease of mass and, consequently, of torsional stresses too