A 2D hydrodynamic-sedimentological model for gravel-bed rivers. Part I: theory and validation

This paper presents a novel 2D-depth average model especially developed for gravel-bed rivers, named Lican-Leufú (Lican=pebble and Leufu=river, in Mapuche’s language, the native inhabitants of Central Patagonia, Argentina). The model consists of three components: a hydrodynamic, a sedimentological, and a morphological model. The flow of water is described by the depth-averaged Reynolds equations for unsteady, free-surface, shallow water flows. It includes the standard k-e model for turbulence closure. Sediment transport can be divided in different size classes (sand-gravel mixture) and the equilibrium approach is used for Exner’s equation. The amour layer is also included in the structure of the model and the surface grain size distribution is also allowed to evolve. The model simulates bank slides that enable channel widening. Models predictions were tested against a flume experiment where a static armour layer was developed under conditions of sediment starvations and general good agreements were found: the model predicted adequately the sediment transport, grain size of transported material, final armour grain size distribution and bed elevation

3_D modeling using TLS and GPR techniques to characterize above and below-ground wood distribution in pyroclastic deposits along the Blanco River (Chilean Patagonia)

To date, the study of in-stream wood in rivers has been focused mainly on quantifying wood pieces deposited above the ground. However, in some particular river systems, the presence of buried dead wood can also represent an important component of wood recruitment and budgeting dynamics. This is the case of the Blanco River (Southern Chile) severely affected by the eruption of Chait\ue9n Volcano occurred between 2008 and 2009. The high pyroclastic sediment deposition and transport affected the channel and the adjacent forest, burying wood logs and standing trees. The aim of this contribution is to assess the presence and distribution of wood in two study areas (483 m2 and 1989 m2, respectively) located along the lower streambank of the Blanco River, and covered by thick pyroclastic deposition up to 5 m. The study areas were surveyed using two different devices, a Terrestrial Laser Scanner (TLS) and a Ground Penetrating Radar (GPR). The first was used to scan the above surface achieving a high point cloud density ( 48 2000 points m-2) which allowed us to identify and measure the wood volume. The second, was used to characterize the internal morphology of the volcanic deposits and to detect the presence and spatial distribution of buried wood up to a depth of 4 m. Preliminary results have demonstrated differences in the numerousness and volume of above wood between the two study areas. In the first one, there were 43 wood elements, 33 standing trees and 10 logs, with a total volume of 2.96 m3 (109.47 m3 km-1), whereas the second one was characterized by the presence of just 7 standing trees and 11 wood pieces, for a total amount of 0.77 m3 (7.73 m3 km-1). The dimensions of the wood elements vary greatly according to the typology, standing trees show the higher median values in diameter and length (0.15 m and 2.91 m, respectively), whereas the wood logs were smaller (0.06 m and 1.12 m, respectively). The low dimensions of deposited wood can be probably connected to their origin, suggesting that these elements were generated by toppling and breaking of surrounding dead trees. Results obtained with the GPR confirm the ability of this instrument to localize the presence and distribution of buried wood. From the 3- D analysis it was possible to assess the spatial distribution and to estimate, as first approach, the volume of the buried wood which represents approximately 0.04% of the entire volcanic deposit. Further analysis will focus on additional GPR calibration with different wood sizes for a more accurate estimation of the volume. The knowledge of the overall wood amount stored in a fluvial system that can be remobilized over time, represent an essential factor to ensure better forest and river management actions

Update on Pathophysiology of Premature Ejaculation: The Bases for New Pharmacological Treatments

Even though premature ejaculation is the most widespread pathology of sexual behavior, it is still considered a psychological disease. Organic etiologies are only now becoming more evident. Premature ejaculation is largely under-diagnosed and under-treated, while erectile dysfunction has received great scientific and clinical attention in recent years. There are plenty of reasons for this: (i) PE is classically considered as psychogenic in nature; (ii) it is traditionally treated with behavioral psychotherapies; (iii) clear and accepted clinical definition(s) are lacking; (iv) the etiologies are largely unknown; (v) the pathogenesis is still obscure - there is a lack of awareness and acknowledgement of PE as a symptom of medical disease; (vi) lacking a medical presence in the field, requests for help from patients are low. Finally, erectile and ejaculatory dysfunctions frequently overlap. For all these reasons, an update on pathophysiology of premature ejaculation is to be considered the base for new pharmacological treatments. © 2006 European Association of Urology and European Board of Urology

Movilidad y reclutamiento de material leñoso de gran tamaño en dos cauces de la Cordillera de la Costa de Chile

In-stream large wood mobility was studied in segments of the main channels of Vuelta de Zorra and Pichún catchments, located in the Coastal Mountain Range, Chile. Statistical significant relationships were found only between bankfull channel width and dependent variables associated to some large wood characteristics measured in the channel reaches. This would indicate that large wood length, and not diameter, would regulate the mobility of the wood pieces during high flows. After the winter season of 2009, the 12 and 6.5 % of the wood elements were mobilized in Vuelta de Zorra and Pichún, respectively. The lower percentage in Pichún would be associated to the lower bankfull width/mean piece length ratio. A statistical non-significant trend was found between mobilized distance and piece length/mean bankfull width; indicating that distance decreased with increased dimensionless piece length. Large wood mobility in the two channels was associated to normal peak flows and could be considered as a minimum mobility rate at annual level. The recruited wood volume was higher than the exported wood volume in both segments, therefore the study period can be considered as an in-stream large wood stocking-period

Material leñoso de gran tamaño en dos cuencas de la Cordillera de la Costa de Chile con diferente historia de uso del suelo

Previous researches indicated that in-stream large wood (LW) depended on the characteristics of the riparian vegetation. This is the first study about LW abundance, longitudinal distribution and sediment trapped by large wood structures comparing two stream segments in catchments with contrasting land use, located in the Coastal Mountain Range, Southern Chile. One such catchment (Vuelta de Zorra) is covered mainly by native forests and the other (Pichún) runs under productive plantations. In a stream segment of each catchment the riparian vegetation was characterized, each LW piece was measured and geo-referenced and the channel morphology was defined. Vegetation along the Vuelta de Zorra channel corresponded to an adult second growth forest ca. 200 years old with a basal area of 69 m² ha-1; while in Pichún, it was a much degraded remnant of old native forests with a basal area of 24 m² ha-1. Considering channel bankfull area as reference, LW volume at Vuelta de Zorra and Pichún was 109 and 56 m³ ha-1, respectively. Trapped sediment values in the stream segments were 82 and 30 m3 km-1 for Vuelta de Zorra and Pichún, respectively; in both channels the accumulations of LW played a key role in the amount of trapped sediment. LW volume was associated with the characteristics of the riparian vegetation which is a consequence of the history of forest interventions and land uses in each catchment

A critical analysis of the role of testosterone in erectile function: From pathophysiology to treatment - A systematic review

Context: Androgen modulation of erectile function (EF) is widely accepted. However, the use of testosterone replacement therapy (TRT) in men with erectile dysfunction (ED) has generated an unprecedented debate. Objective: To summarize the relevant data on the incidence, diagnosis, and management of ED coexisting with hypogonadism and to develop a pathophysiology-based treatment algorithm. Evidence acquisition: We reviewed the relevant medical literature, with a particular emphasis on original molecular studies, prospective observational data, and randomized controlled trials performed in the past 20 yr. Evidence synthesis: Testosterone modulates nearly every component involved in EF, from pelvic ganglions to smooth muscle and the endothelial cells of the corpora cavernosa. It also regulates the timing of the erectile process as a function of sexual desire, coordinating penile erection with sex. Epidemiologic studies confirm the significant overlap of hypogonadism and ED; however, most guidelines do not consider the differential diagnosis of hypogonadism or the relevance of subclinical disease. Various clinical tools can help the physician to assess and restore androgen levels in men with ED. Special attention is given to fertility-sparing treatments, due to the increasing number of older men desiring fatherhood. The simultaneous use of phosphodiesterase type 5 inhibitors (PDE5-Is) and TRT has recently been questioned. Originally proposed as a salvage therapy for nonresponders to PDE5-Is, this approach has been inappropriately transformed into a combination therapy. Clinical data are consistent when reinterpreted in the proper framework, whereas molecular evidence remains controversial. Conclusions: A body of molecular and clinical evidence supports the use of TRT in hypogonadal patients with ED, although the benefit-risk ratio is uncertain in advanced age. Critical appraisal of this evidence enabled the development of a pathophysiology-oriented algorithm designed to avoid inappropriate treatments and support whether to start with TRT, PDE5-I only, or both. Apparently divergent findings are reconciled when TRT is correctly indicated. An improved diagnosis and individualized management is desirable in light of the many available options. © 2013 European Association of Urology

The SIAMS-ED Trial: A National, Independent, Multicentre Study on Cardiometabolic and Hormonal Impairment of Men with Erectile Dysfunction Treated with Vardenafil

Increased cardiovascular risk has been associated with reduced response to proerectile drugs. The Italian Society of Andrology and Sexual Medicine (SIAMS) promoted an independent, multicenter study performed in 604 men (55 ± 12 yrs) suffering from erectile dysfunction (ED) to assess multiple health outcomes and response to 6-month vardenafil challenge in a real-life setting. Overall, 30.8% men had metabolic syndrome. Cardiovascular risk stratification revealed a greater number of ED subjects with moderate risk of a major adverse cardiovascular event than the general population (P < 0.01). Age-adjusted pulse pressure was positively correlated with ED severity and negatively with androgens and waist circumference (P < 0.01). A decline in total testosterone was observed with increasing arterial pulse pressure (P < 0.05), which was not accompanied by compensatory LH rise. Follow-up on 185 men treated with vardenafil in an nonrandomized, open, single-arm trial documented a significant rise in IIEF-5 (delta = 6.1 ± 4.8) that was maintained in men with high cardiovascular risk. Mild adverse events occurred in <5%, with no differences between cardiovascular risk classes. In summary, ED is a frequent symptom in patients with an elevated, but often unknown, risk of future cardiovascular events. Androgens predict vascular resistance in ED patients. Vardenafil's response and safety profile were preserved in subjects with higher cardiovascular risk

Measurement of the prompt J/psi and psi(2S) polarizations in pp collisions at sqrt(s) = 7 TeV

The polarizations of prompt J/psi and psi(2S) mesons are measured in proton-proton collisions at sqrt(s) = 7 TeV, using a dimuon data sample collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 4.9 inverse femtobarns. The prompt J/psi and psi(2S) polarization parameters lambda[theta], lambda[phi], and lambda[theta, phi], as well as the frame-invariant quantity lambda(tilde), are measured from the dimuon decay angular distributions in three different polarization frames. The J/psi results are obtained in the transverse momentum range 14 &lt; pt &lt; 70 GeV, in the rapidity intervals abs(y) &lt; 0.6 and 0.6 &lt; abs(y) &lt; 1.2. The corresponding psi(2S) results cover 14 &lt; pt &lt; 50 GeV and include a third rapidity bin, 1.2 &lt; abs(y) &lt; 1.5. No evidence of large transverse or longitudinal polarizations is seen in these kinematic regions, which extend much beyond those previously explored

Schadevergoeding bij overlijden: een stoel die een soort tafeltje is

In het aansprakelijkheidsrecht heeft een benadeelde in beginsel recht op volledige vergoeding van zijn schade. De gevolgen van de schadetoebrengende gebeurtenis dienen zoveel als mogelijk te worden weggenomen of te worden gecompenseerd. Daarbij wordt gekeken naar de situatie waarin de benadeelde zou hebben verkeerd indien de schadetoebrengende gebeurtenis niet zou hebben plaatsgevonden. Dat is bij overlijden per definitie problematisch. Er is iemand weggevallen, wat vele gevolgen heeft. De schade als gevolg van het overlijden komt maar beperkt voor vergoeding in aanmerking. In artikel 6:108 BW is een drietal beperkingen te vinden. Het gaat hier om beperkingen ten aanzien van de aard van de schade, de kring van gerechtigden en de omvang van de schade. Daarbij hinkt het recht op schadevergoeding bij overlijden op twee gedachten. Aan de ene kant is er het aansprakelijkheidsrecht, maar de geleden schade komt niet volledig voor vergoeding in aanmerking. Aan de andere kant is er het recht op alimentatie uit het familierecht, maar dat wordt bij overlijden niet consequent toegepast. De motieven voor de beperkingen van het recht op schadevergoeding zijn achterhaald en niet (langer) overtuigend. Het recht is niet bij de tijd, het sluit niet aan bij de maatschappelijke ontwikkelingen. De beperkingen die het recht op schadevergoeding bij overlijden in de huidige samenleving met zich meebrengt zorgen voor complexe methoden om de nabestaanden tegemoet te komen en oogsten daardoor veel kritiek. In deze bijdrage wordt die kritiek besproken. De bijdrage wordt afgesloten met enkele denkrichtingen voor nader onderzoek