A Measurement Study on the Advertisements Displayed to Web Users Coming from the Regular Web and from Tor

Online advertising is an effective way for businesses to find new customers and expand their reach to a great variety of audiences. Due to the large number of participants interacting in the process, advertising networks act as brokers between website owners and businesses facilitating the display of advertisements. Unfortunately, this system is abused by cybercriminals to perform illegal activities such as malvertising. In this paper, we perform a measurement of malvertising from the user point of view. Our goal is to collect advertisements from a regular Internet connection and using The Onion Router in an attempt to understand whether using different technologies to access the Web could influence the probability of infection. We compare the data from our experiments to find differences in the malvertising activity observed. We show that the level of maliciousness is similar between the two types of accesses. Nevertheless, there are significant differences related to the malicious landing pages delivered in each type of access. Our results provide the research community with insights into how ad traffic is treated depending on the way users access Web content

MODELO EXPLICATIVO DEL PRECIO SPOT DEL MINERAL DE HIERRO

The objective of this study was to construct an explanatory model of the spot price of iron ore in the international market. For this, the method of multiple linear regressions was used. As a dependent variable, the spot price of iron ore (62% Fe) China Tianjin port was taken, between 2010 and 2013. As independents variables were taken seven variables of international iron ore market. The resulting model includes variables: Iron ore inventory in Chinese ports, Baltic Dry Index (BDI), Iron ore exports from Brazil & Australia and Chinese Rebar Steel Price, as explanatory variables of the behavior of the spot price of iron ore in the international market. The model has an adjusted coefficient of determination R2 of 0.90, and was validated by comparing its predictions vs. known values of 2014.El objetivo de este estudio fue construir un modelo explicativo del precio Spot del mineral de hierro en el mercado internacional. Para ello se utilizó el método de regresión lineal múltiple. Como variable dependiente, se tomó el precio Spot del mineral de hierro (62% Fe) puerto Tianjin China, entre los años 2010 y 2013. Como variables independientes fueron tomadas 7 variables del mercado internacional de mineral de hierro. El modelo resultante incluye a las variables: Inventario de mineral en puertos de China, “Baltic Dry Index” (BDI), Exportaciones de mineral de Australia + Brasil y el Precio del “Rebar” de China, como las variables explicativas del comportamiento del precio spot del mineral de hierro en el mercado internacional. El modelo tiene un coeficiente de determinación ajustado R2  de 0.90, y fue validado mediante la comparación de sus pronósticos vs. valores conocidos de 2014

El poder de servir en un mundo de paradojas

Cuando se escribe un libro debemos tener en la mente al público lector, porque escribimos para los estudiantes y para el público lector. Luis Yerovi escribe para los estudiantes y también para el público. Tiene su estilo propio que, ha logrado a través del tiempo, con sus conversaciones en el aula, conversatorios diríamos, diálogos que le han permitido elaborar un texto ameno, rico en pensamiento metafórico, a manera de los relatos o narraciones de vida de las personas o de las ciudades, que nos atraen tanto.Universidad Tecnológica Indoaméric

Adaptação cultural e validação da versão portuguesa do questionário Medical Outcomes Study Social Support Survey (MOS-SSS)

O objectivo deste trabalho é calcular as propriedades psicométricas da versão portuguesa do questionário Medical Outcomes Study Social Support Survey (MOS-SSS). Este questionário foi traduzido e adaptado à cultura portuguesa. A amostra é constituída por 101 doentes com doença crónica, utentes de um centro de saúde rural de Portugal. A idade média é 63,4 anos; 56,4% são mulheres. 29% são analfabetos e 2% possuem estudos superiores. 78% sofrem de hipertensão arterial e 56,4% sofrem de diabetes mellitus tipo 2. A consistência interna foi avaliada com o alpha de Cronbach. Depois, foi realizada uma análise factorial exploratória e confirmatória com o objectivo de confirmar a validade e fiabilidade da escala e as suas características multidimensionais. A confiabilidade teste-reteste realizada às duas semanas foi estimada usando a análise kappa ponderado para as variáveis ordinais e o coeficiente de correlação intraclasse para as variáveis quantitativas. A alpha de Cronbach para as subescalas varia entre 0,873 e 0,967 no teste e 0,862 e 0,972 no reteste. A análise factorial exploratória revelou a existência de quatro factores (apoio emocional, material, afectivo e interacção social positiva) que explicam o 72,71% da variância. A análise factorial confirmatória permite concluir a existência destes quatro factores que permitem a aplicação da escala com os itens do questionário original. Os índices de ajustamento são satisfatórios e verificam a estrutura inicial, apresentando valores de χ2/df =2,01; GFI =0,998; CFI=0,999; AGFI =0,998; TLI =0,999; NFI =0,998; SRMR =0,332; RMSEA =0,76. A confiabilidade teste-reteste às duas semanas da versão portuguesa do MOS-SSS foi estimada pelo coeficiente de correlação intraclasse que variou entre 0,941 e 0,966 para as quatro dimensões do questionário e para o índice de apoio total. Os índices kappa ponderados variaram entre 0,67 e 0,87 para todos os itens. A versão portuguesa do MOS-SSS demonstrou boas características psicométricas e parece ser útil para avaliar as características multidimensionais do apoio social em população portuguesa.The aim of this study was the assesment of psychometric properties of the Portuguese version of the instrument «Medical Outcomes Study – Social Support Survey (MOSSSS) ». This questionnaire has been translated and adapted in a Portuguese sample of 101 patients with chronic illness of a rural health centre in Portugal. The average age of patients was 63.4 years, 56.4% female. 29% were illiterate and 2% had completed high school. 78% had arterial hypertension and the 56.4% had diabetes mellitus type 2. The internal consistency was evaluated using Cronbach’s alpha. Exploratory and Confirmatory factor analysis were performed in order to confirm reliability and validity of the scale and its multidimensional characteristics. The 2-week test-retest reliability was estimated using weighted kappa for the ordinals variables and intraclass coefficient correlation for the quantitative variables. Cronbach’s alphas for the subscales ranged from 0.873 to 0.967 at test, and 0.862 to 0.972 at retest. Exploratory factor analysis revealed the existence of four factors (emotional, tangible, positive interaction and affection support) that explain the 72.71% of the variance. Confirmatory factor analysis supported the existence of four factors that allowed the application of the scale with original items. The goodness-of-fit measures corroborate the initial structure, with χ2/ df=2.01, GFI=0.998, CFI=0.999, AGFI=0.998, TLI=0.999, NFI=0.998, SRMR=0.332, RMSEA=0.76. The 2-weeks test-retest reliability of the Portuguese MOS-SSS as measured by the intraclass correlation coefficient was ranged from 0.941 to 0.966 for the four dimensions and the overall support index. The weighted kappa was ranged from 0.67 to 0.87 for all the items. The MOS-SSS Portuguese version demonstrates good psychometric properties and seems to be useful to measure multidimensional aspects of social support in the Portuguese population.Sociedade Espanhola de Medicina Familiar e Comunitária (SEMFYC

New method for analytical photovoltaic parameters identification: meeting manufacturer’s datasheet for different ambient conditions

At present, photovoltaic energy is one of the most important renewable energy sources. The demand for solar panels has been continuously growing, both in the industrial electric sector and in the private sector. In both cases the analysis of the solar panel efficiency is extremely important in order to maximize the energy production. In order to have a more efficient photovoltaic system, the most accurate understanding of this system is required. However, in most of the cases the only information available in this matter is reduced, the experimental testing of the photovoltaic device being out of consideration, normally for budget reasons. Several methods, normally based on an equivalent circuit model, have been developed to extract the I-V curve of a photovoltaic device from the small amount of data provided by the manufacturer. The aim of this paper is to present a fast, easy, and accurate analytical method, developed to calculate the equivalent circuit parameters of a solar panel from the only data that manufacturers usually provide. The calculated circuit accurately reproduces the solar panel behavior, that is, the I-V curve. This fact being extremely important for practical reasons such as selecting the best solar panel in the market for a particular purpose, or maximize the energy extraction with MPPT (Maximum Peak Power Tracking) methods

A Nonionic Alcohol Soluble Polymer Cathode Interlayer Enables Efficient Organic and Perovskite Solar Cells

The choice of interfacial materials and their properties play a critical role in determining solar cell performance and stability. For compatibility with roll-to-roll printing, it is desirable to develop stable cathode interface layers (CILs) that can be processed over the photoactive layer using orthogonal solvents. In this study, an n-type naphthalene diimide core and oligo (ethylene glycol) side-chain-based conjugated polymer is reported as a universal, efficient CIL for organic and perovskite photovoltaics. Besides good thermal stability and easy processing in alcohol/water, the new CIL is found to possess electron transport properties with an electrical conductivity of 2.3 × 10^{–6} S cm^{–1}, enabling its use as a CIL with a film thickness of up to ∼35(±2) nm. Utilizing the new CIL, 16% power conversion efficiency (PCE) is achieved for organic solar cells (OSCs) based on the PM6-Y6 photoactive layer (8.9% PCE for no CIL and 15.1% with state-of-the-art CIL, PDINO), and perovskite solar cells from methylammonium lead iodide yielded a PCE of 17.6%. Compared to the reference devices, the new CIL reduced trap-assisted carrier recombination and increased the built-in potential by 80 mV, simultaneously enhancing all photovoltaic parameters. Moreover, new CIL based devices had better photostability with no burn-in losses

Inclusion of new 5-fluorouracil amphiphilic derivatives in liposome formulation for cancer treatment

Correction for 'Inclusion of new 5-fluorouracil amphiphilic derivatives in liposome formulation for cancer treatment' by M. Petaccia et al., Med. Chem. Commun., 2015, 6, 1639–1642

Antioxidant activity and characterization of whey protein-based beverages: Effect of shelf life and gastrointestinal transit on bioactivity

Whey proteins can exhibit antioxidant activity. The objectives of this study were to formulate model whey based beverages with well-established antioxidants (plant polyphenols, vitamins and astaxanthin) to investigate (1) the antioxidant shelf life over a 24-week period and (2) the antioxidant activity after upper gastrointestinal transit. Pilot scale processing (pasteurization, ultra-high temperature or spray drying) was used to prepare beverages which were representative of current product formats. In vitro gastrointestinal digestion of test samples was performed using the standardised INFOGEST method and antioxidant activity of samples was determined using ABTS, FRAP and ORAC. Results from the antioxidant shelf life study provided evidence that powder products functionality was preserved. Whey beverages (pasteurised or spray dried) increased or maintained antioxidant activity during gastrointestinal transit. Combination of whey with additional antioxidant ingredients increased the bioactivity of formulated products; however, this greater bioactivity was altered after gastrointestinal transit, depending on processing type and antioxidant methodology. Industrial relevance: Whey protein-based antioxidant beverages could benefit the elderly consumer to meet their increased protein requirements and boost their antioxidant status. Consumer's acceptance for whey protein-based beverages often improves with clear formulations. This work generated whey protein-based UHT beverages with greater stability and clarity than pasteurised formulations. A novel combination of plant and marine antioxidants increased antioxidant activity of whey protein-based formulations. Furthermore, to suit export markets this work generated spray dried whey protein formulations that did not alter antioxidant potentialThis work was funded by the Irish Department of Agriculture, Food and the Marine, FIRM 13F354-WheyGSH and 15F604-TOMI). A. R. Corrochano was in receipt of a Teagasc Walsh Fellowship. E. Arranz also received funding from Enterprise Ireland (MF2018-0151) and the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 71365

Affordable laparoscopic simulator to acquire basic skills in undergraduate surgery students

Background: The simulation emerges as an option that allows students to practice in a safe environment, all this in a scenario that resembles the real situation.Methods: We developed a prototype of a low-cost simulator that mimics the dimensions of the abdominal cavity and allows the undergraduate students to acquire the basic skills in minimally invasive surgery.Results: In the 10 competencies evaluated, statistically significant improvement was found in both groups being higher in the students who were trained by our simulator of laparoscopic surgery compared with students who attended surgeries and participated as seconds assistants, taking as reference a value of p ≤0.05.Conclusions: The simulation as new teaching strategy generates a real environment and scenarios that can be recreated in multiple occasions, being able to change depending on the objectives for the acquisition of skills. This simulator gives the user skills for more types of simulation as it progresses in its surgical training

Backbone-driven host-dopant miscibility modulates molecular doping in NDI conjugated polymers

Molecular doping is the key to enabling organic electronic devices, however, the design strategies to maximize doping efficiency demands further clarity and comprehension. Previous reports focus on the effect of the side chains, but the role of the backbone is still not well understood. In this study, we synthesize a series of NDI-based copolymers with bithiophene, vinylene, and acetylenic moieties (P1G, P2G, and P3G, respectively), all containing branched triethylene glycol side chains. Using computational and experimental methods, we explore the impact of the conjugated backbone using three key parameters for doping in organic semiconductors: energy levels, microstructure, and miscibility. Our experimental results show that P1G undergoes the most efficient n-type doping owed primarily to its higher dipole moment, and better host–dopant miscibility with N-DMBI. In contrast, P2G and P3G possess more planar backbones than P1G, but the lack of long-range order, and poor host–dopant miscibility limit their doping efficiency. Our data suggest that backbone planarity alone is not enough to maximize the electrical conductivity (σ) of n-type doped organic semiconductors, and that backbone polarity also plays an important role in enhancing σ via host–dopant miscibility. Finally, the thermoelectric properties of doped P1G exhibit a power factor of 0.077 μW m−1 K−2, and ultra-low in-plane thermal conductivity of 0.13 W m−1K−1 at 5 mol% of N-DMBI, which is among the lowest thermal conductivity values reported for n-type doped conjugated polymers