Irrationality and quasiperiodicity in driven nonlinear systems

We analyse the relationship between irrationality and quasiperiodicity in nonlinear driven systems. To that purpose we consider a nonlinear system whose steady-state response is very sensitive to the periodic or quasiperiodic character of the input signal. In the infinite time limit, an input signal consisting of two incommensurate frequencies will be recognised by the system as quasiperiodic. We show that this is in general not true in the case of finite interaction times. An irrational ratio of the driving frequencies of the input signal is not sufficient for it to be recognised by the nonlinear system as quasiperiodic, resulting in observations which may differ by several orders of magnitude from the expected quasiperiodic behavior. Thus, the system response depends on the nature of the irrational ratio, as well as the observation time. We derive a condition for the input signal to be identified by the system as quasiperiodic. Such a condition also takes into account the sub-Fourier response of the nonlinear system.Comment: accepted in Phys. Rev. Let

Public-Private Partnerships: Unmasking the reality

PUBLIC-PRIVATE Partnerships (PPPs) are long-term contractual arrangements where the private sector provides (builds and sometimes runs) infrastructure assets and services that have traditionally been directly funded by the government, such as hospitals, schools, prisons, roads, bridges, tunnels, railways, and water and sanitation plants, and where there is also some form of risk sharing between the public and the private sector. These arrangements started in the 1990s in developed countries and now many developing countries are trying them. In this Policy Brief, first, it scrutinized the arguments to justify these contractual arrangements and the available evidence about their proclaimed benefits. Then we discuss Philippine PPPs

Técnicas de encaminamiento en redes ad-hoc basadas en criterios de potencia y batería

Las redes ad hoc están formadas únicamente por terminales móviles que funcionan a partir de baterías, es decir, no hay estaciones base. El consumo de energía es, por lo tanto, un punto muy importante ala hora de diseñar la red. Paramax.imizar el tiempo de vida de una red ad hoc, el consumo de energía tiene que ser distribuido de forma equitati va entre el conjunto de nodos que la forman, y a la vez ha de rIÚnirnizarse el consumo total de energía para cada transmisión. Los algoritmosdeencarninarniento clásicos para ad hoc no tienen en cuenta la energía y por tanto no consiguen maximizar el tiempo de vida de la red. En este artículo se hace un estudio del estado del arte en métricas de encaminamiento que tengan en cuenta la batería al seleccionar las rutas y se proponen nuevas métricas al respecto. Dichas métricas se comparan mediante simulación intentando llegar a un compromiso entre parámetros como el tiempo de vida de la red y la calidad de servicio, entre otros.Peer Reviewe

Alumina and zirconia as inhibitors of crystallization during sintering of borosilicate glasses

The glass composition (in mol%) 16 Na2O ∙ 24 B2O3 ∙ 60 SiO2 has suitable viscosity and dilatometric properties to be used as sealing material for the gas manifolds of molten carbonate fuel cells (MCFC). Nevertheless, quartz crystallization takes place during sintering of the borosilicate glass powder at temperatures between 600 and 700 °C. The quartz crystallization leads to the formation of pores and a variation in the thermal expansion coefficient; both giving rise to defects and tensions in the seal. In this work, the possibility of inhibition of quartz crystallization by substituting AI2O3 or ZrO2 for 2 or 5 mol% of SiO2 is described. The thermal properties and the viscosity-temperature curve of the new compositions, especially those containing alumina do not differ much from the original glass

EUropean prospective cohort study on Enterobacteriaceae showing REsistance to CArbapenems (EURECA): a protocol of a European multicentre observational study

Introduction: The rapid worldwide spread of carbapenem-resistant Enterobacteriaceae (CRE) constitutes a major challenge. The aim of the EUropean prospective cohort study on Enterobacteriaceae showing REsistance to CArbapenems (EURECA), which is part of the Innovative Medicines Initiative Joint Undertaking (IMI JU) funded COMBACTE-CARE project, is to investigate risk factors for and outcome determinants of CRE infections to inform randomised clinical trial designs and to provide a historical cohort that could eventually be used for future comparisons with new drugs targeting CRE. Methods: A multicentre (50 sites), multinational (11 European countries), analytical observational project was designed, comprising 3 studies. The aims of study 1 (a prospective cohort study) include characterising the features, clinical management and outcomes of hospitalised patients with intra-abdominal infection, pneumonia, complicated urinary tract infections and bloodstream infections caused by CRE (202 patients in each group). The main outcomes will be 30-day all-cause mortality and clinical response. Study 2 (a nested case–control study) will identify the risk factors for target infections caused by CRE; 248 selected patients from study 1 will be matched with patients with carbapenem-susceptible Enterobacteriaceae (1:1) and with hospitalised patients (1:3) and will provide a historical cohort of patients with CRE infections. Study 3 (a matched cohort study) will follow patients in study 2 in order to assess mortality, length of stay and hospital costs associated with CRE. All patients will be followed for 30 days. Different, up-to-date statistical methods will be applied to come to unbiased estimates for all 3 studies. Ethics and dissemination: Before-study sites will be initiated, approval will be sought from appropriate regulatory agencies and local Ethics Committees of Research or Institutional Review Boards (IRBs) to conduct the study in accordance with regulatory requirements. This is an observational study and therefore no intervention in the diagnosis, management or treatment of the patients will be required on behalf of the investigation. Any formal presentation or publication of data collected from this study will be considered as a joint publication by the participating physician(s) and will follow the recommendations of the International Committee of Medical Journal Editors (ICMJE) for authorship.Innovative Medicine Initiative (IMI)European Union's Seventh Framework Programme (FP7)Spanish Network for Research in Infectious Diseases [REIPI RD12/0015, RD16/2016

Aphicidal activity of farnesol against the green peach aphid – Myzus persicae

BACKGROUND: Myzus persicae (Hemiptera: Aphididae) is considered one of most important agricultural pests in the world. It is one of the main pests in protected pepper crops under glasshouse conditions in Southeastern Spain, but its control is limited as a consequence of the few available authorized insecticides and their incompatibility with the natural enemies. Some essential oils and pure compounds such as anise (Pimpinella anisum) or farnesol are repellent and/or toxic to aphids. Their use as a botanical insecticides can be an alternative for aphid control in pepper. RESULTS: The effect of farnesol was evaluated against M. persicae in a new bioassay developed to test the contact effect (aqueous formulation of the products) on aphids in laboratory conditions. Aniseed essential oil, geraniol and (Z)-jasmone at 0.6% causes an aphid mortality of >50%; and farnesol was the most effective (93.67% mortality). Farnesol nanoemulsions between 0.2% and 0.6% were formulated with an IKA-Labor Pilot dispersing machine (7940 rpm for 10 min) using Tween 80 as a surfactant. These formulations were tested on field experiments (glasshouse conditions) on pepper crops for 2 years. Foliar applications of farnesol at a concentration of 0.4% in field conditions causes a high reduction in aphid populations, with efficacies of ≈70–80% with respect to the control, similar to or even higher than the efficacy of the reference pyrethrin insecticide. CONCLUSION: Farnesol showed a great aphicidal effect against M. persicae. The use of this molecule in integrated pest management programs combined with natural enemies is a good option for future control of M. persicae

Aniseed essential oil botanical insecticides for the management of the currant-lettuce aphid

Nasonovia ribisnigri Mosley (Hemiptera: Aphididae) is the most damaging aphid species of lettuce grown in open fields. Populations of N. ribisnigri are developing resistance to insecticides, making their control difficult. Botanicals are an alternative for pest control. Aniseed (Pimpinella anisum L.) is a relevant crop in the production of essential oils. The effect of aqueous nano-formulations of this oil and its main compound (E)-anethole were tested against N. ribisnigri in a growth chamber, a greenhouse (in spring for two years, 2019 and 2020) and in the open field in a plot in the Southeast of Spain (Torrepacheco, Murcia) in May 2019. Aniseed essential oil nanoemulsions were prepared using a laboratory dispersing machine at a high-speed regime (10 min, 7940 revs/min, 15 ◦C) using Tween80 as a surfactant at a 1:2 ratio. Foliar applications of aniseed essential oil at concentrations of 0.2% and 0.4% (0.1 and 0.2 mL respectively) to lettuce plants infested with homogeneous populations of N. ribisnigri reduced the number of insects compared with the control in the laboratory (efficacies > 50%) and greenhouse (efficacies > 25%, 48 h after treatment) experiments. During the field trial, a reduction in the aphid populations was also produced after the application of the products, without any phytotoxic effects observed on the crop. Likewise, (E)-anethole gave similar results as aniseed essential oil (with efficiencies of up to 47% with respect to the control) without damaging the plant