Dynamical models for sand ripples beneath surface waves

We introduce order parameter models for describing the dynamics of sand ripple patterns under oscillatory flow. A crucial ingredient of these models is the mass transport between adjacent ripples, which we obtain from detailed numerical simulations for a range of ripple sizes. Using this mass transport function, our models predict the existence of a stable band of wavenumbers limited by secondary instabilities. Small ripples coarsen in our models and this process leads to a sharply selected final wavenumber, in agreement with experimental observations.Comment: 9 pages. Shortened version of previous submissio

A comparison of Optisoap versus commercial soap in preventing protein deposition on hydrophilic contact lenses

This study compared the effectiveness of Optisoap versus other commericial hand soaps in preventing protein deposition of hydrophilic contact lenses due to soap residues. Twelve clean lenses were halved, treated with Optisoap or a commercial soap, and placed in a protein solution. The lenses were inspected for protein deposits after thirty and sixty minutes. No significant difference was found between the Optisoap or the commercial soaps

Fiscal policies and car choices in Italy and Norway: A scenario analysis based on a stated-preference survey

Norwegian and Italian car drivers make very different car choices. This paper investigates the influence of fiscal policies on car buyers’ choices, using data collected from a stated preference survey conducted in 2021. After estimating a joint random parameter logit model, we simulated the market shares of five car powertrains under three scenarios: “Italian car buyers face the same net purchase car prices and fuel\electricity costs as the Norwegian car drivers and vice versa”, “Italy adopts the Norwegian registration tax”, and “Both Italy and Norway adopt a social cost internalizing registration tax”. The results indicate that Italian car users are reluctant to switch to battery electric cars (BEVs). They would choose BEVs more frequently in the three scenarios envisaged but without reaching the corresponding Norwegian levels. If Italy would adopt the Norwegian registration tax system, BEVs’ market share would gain 5.4 percentage points relative to the baseline scenario, while under the social cost internalizing scenario, BEVs’ market share would improve by 3.4 and PHEVs’ one by 0.2 percentage points. On the contrary, Norwegians are BEV-oriented and would comparatively preserve a high BEV share. In the social cost internalization scenario, the BEV share relative to the baseline scenario would decrease by 7.2 percentage points, petrol cars would gain 1.2, HEVs 2.9, PHEVs 3.4, and diesel cars would lose 0.3 percentage points. In general, there seems to be a lock-in or path dependence effect that limits BEV penetration in Italy and prevents the decline of the BEV share in Norway

XAS investigation of silica aerogel supported cobalt rhenium catalysts for ammonia decomposition.

The implementation of ammonia as a hydrogen vector relies on the development of active catalysts to release hydrogen on-demand at low temperatures. As an alternative to ruthenium-based catalysts, herein we report the high activity of silica aerogel supported cobalt rhenium catalysts. XANES/EXAFS studies undertaken at reaction conditions in the presence of the ammonia feed reveal that the cobalt and rhenium components of the catalyst which had been pre-reduced are initially re-oxidised prior to their subsequent reduction to metallic and bimetallic species before catalytic activity is observed. A synergistic effect is apparent in which this re-reduction step occurs at considerably lower temperatures than for the corresponding monometallic counterpart materials. The rate of hydrogen production via ammonia decomposition was determined to be 0.007 molH2 gcat−1 h−1 at 450 °C. The current study indicates that reduced Co species are crucial for the development of catalytic activity

A literature review and survey of childhood pneumonia etiology studies: 2000-2010.

The Pneumonia Etiology Research for Child Health (PERCH) project is the largest multicountry etiology study of childhood pneumonia since the Board on Science and Technology in International Development studies of the 1980s. However, it is not the only recent or ongoing pneumonia etiology study, and even with seven sites, it cannot capture all epidemiologic settings in the developing world. Funding providers, researchers and policymakers rely on the best available evidence to strategically plan programs, new research directions and interventions. We aimed to describe the current landscape of recent pneumonia etiology studies in children under 5 years of age in the developed and developing world, as ascertained by a literature review of relevant studies with data since the year 2000 and a survey of researchers in the field of childhood pneumonia. We collected information on the study population, study design, case definitions, laboratory samples and methods and identified pathogens. A literature review identified 88 studies with child pneumonia etiology results. As of June 2010, our survey of researchers identified an additional 65 ongoing and recently completed child pneumonia etiology studies. This demonstrates the broad existing context into which the PERCH study must be placed. However, the landscape analysis also reveals a multiplicity of case definitions, levels of clinician involvement, facility types, specimen collection, and laboratory techniques. It reinforces the need for the standardization of methods and analyses for present and future pneumonia etiology studies in order to optimize their cumulative potential to accurately describe the microbial causes of childhood pneumonia

Three-year results from a preclinical implantation study of a long-term resorbable surgical mesh with time-dependent mechanical characteristics

PURPOSE: The purpose of this study was to evaluate the biocompatibility, local tissue effects and performance of a synthetic long-term resorbable test mesh (TIGR(®) Matrix Surgical Mesh) compared to a non-resorbable polypropylene control mesh following implantation in a sheep model. METHODS: Full-thickness abdominal wall defects were created in 14 sheep and subsequently repaired using test or control meshes. Sacrifices were made at 4, 9, 15, 24 and 36 months and results in terms of macroscopic observations, histology and collagen analysis are described for 4, 9, 15, 24 and 36 months. RESULTS: The overall biocompatibility was good, and equivalent in the test and control meshes while the resorbable mesh was characterized by a collagen deposition more similar to native connective tissue and an increased thickness of the integrating tissue. The control polypropylene mesh provoked a typical chronic inflammation persistent over the 36-month study period. As the resorbable test mesh gradually degraded it was replaced by a newly formed collagen matrix with an increasing ratio of collagen type I/III, indicating a continuous remodeling of the collagen towards a strong connective tissue. After 36 months, the test mesh was fully resorbed and only microscopic implant residues could be found in the tissue. CONCLUSIONS: This study suggests that the concept of a long-term resorbable mesh with time-dependent mechanical characteristics offers new possibilities for soft tissue repair and reinforcement

Effective Communication About Pregnancy, Birth, Lactation, Breastfeeding and Newborn Care:The Importance of Sexed Language

On 24 September 2021, The Lancet medical journal highlighted an article on its cover with a single sentence in large text; “Historically, the anatomy and physiology of bodies with vaginas have been neglected.” This statement, in which the word “women” was replaced with the phrase “bodies with vaginas,” is part of a trend to remove sexed terms such as “women” and “mothers” from discussions of female reproduction. The good and important intention behind these changes is sensitivity to, and acknowledgment of, the needs of people who are biologically female and yet do not consider themselves to be women because of their gender identity (1). However, these changes are often not deliberated regarding their impact on accuracy or potential for other unintended consequences. In this paper we present some background to this issue, describe various observed impacts, consider a number of potentially deleterious consequences, and suggest a way forward

Fish Structure in Channel Networks of a Large Anabranching Floodplain: Effect of Isolation/Connection Processes

Channel networks of floodplain rivers are the main routes for water, sediment, organic matter, and aquatic organisms between main channels and lakes, playing a substantial role in floodplain dynamics. Despite their importance most investigations in large floodplain rivers focus on main channels and lentic water bodies. This research deals with fish assemblage variations in different lotic sites (scour holes and straight reaches) of one of the many channels which shape the wide anabranching floodplain of the middle reach of the Paraná River. We considered the influence of environmental factors, such as hydro-geomorphological features and water quality of the channel, connections with surrounding lentic water bodies, seasonality, and interannual flow variations. The results showed two main ecological patterns closely related to floodplain connectivity. In-channel habitat heterogeneity has low influence on fish assemblages when minor channels are connected to significant flooded areas (sampling period 2013–2016). Spatial or temporal predictions of fish structure during these stages are not easy due to the interaction of several environmental factors. However, during very low water levels (winter of 2018) most lentic areas become isolated from the nearby channel network, and floodplain fish are forced to move into the numerous scour holes of the floodplain channels where water conditions resemble those in lentic habitats. Our work highlights the importance of in-channel characteristics of floodplain river networks and their crucial role for fish conservation, particularly during very low water stages.Fil: Abrial, Elie. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Espínola, Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Amsler, Mario Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Rabuffetti, Ana Pia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Latosinski, Francisco Guillermo. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas. Departamento de Hidráulica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Szupiany, Ricardo Nicolas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas. Departamento de Hidráulica; ArgentinaFil: Eurich, María Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Blettler, Martin Cesar Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; Argentin

COx-free hydrogen production from ammonia – mimicking the activity of Ru catalysts with unsupported Co-Re alloys

On-demand production of hydrogen from ammonia is a challenge limiting the implementation of ammonia as a long term hydrogen vector to overcome the difficulties associated with hydrogen storage. Herein, we present the development of catalysts for the on-demand production of hydrogen from ammonia by combining metals with high and low N-adatom adsorption energies. In this way, cobalt-rhenium (Co-Re) catalysts show high activity mimicking that of ruthenium. EXAFS/XANES analyses demonstrate that the bimetallic Co-Re contribution is responsible for the activity and the stability of the catalysts in consecutive runs with no observable formation of nitrides (Co-N and Re-N) occurring under the ammonia atmosphere. While cobalt is partially re-oxidised under ammonia, re-reduction in the presence of rhenium is observed at higher temperatures, coinciding with the on-set of catalytic activity which is accompanied by minor structural changes. These results provide insight for the development of highly active alloy based ammonia decomposition catalysts