Social and attitudinal determinants of viral marketing dynamics

At this time of uncertainty, viral marketing is emerging as one of the most intriguing communication strategies, due to low cost and the results it obtains. However, the success of this kind of practice depends on a range of factors including what we explore and refer to in the present research as the individual’s “viral dynamics”. We thus propose a causal model in which viral dynamics is determined by the individual’s social capital and prior attitudes. Based on a survey of young adults, the authors test the effects of structural and relational capital as well as attitudes on viral dynamics. The results evidence that the individual’s connectedness in the email network does not impact viral dynamics, whereas the individual’s integration and relationship with the network and the attitudes towards viral messages prove critical to the individual involved in the receiving-forwarding process.     

Viscoelastic properties of poly(vinyl alcohol) hydrogels and ferrogels obtained through freezing-thawing cycles

We report the preparation of poly(vinyl alcohol) (PVA) hydrogels obtained through freezing-thawing cycles. The viscoelastic properties of these gels using parallel-plate shear mode were evaluated as a function of temperature, time, degree of swelling, concentration and the number of freezing-thawing cycles. The storage modulus was analyzed on the basis of a theoretical model based on the scaling approach. These results provide additional evidence for a non-crystalline nature of the structure of PVA cryogels.Furthermore, PVA ferrogels have been prepared from PVA aqueous solutions and a ferrofluid through freezing-thawing cycles. The viscoelastic properties of these materials have been evaluated. It is shown that the variation of the storage modulus with ferrofluid concentration cannot be fitted using classical theories what has been attributed to the small dimensions of the particles in the ferrogels and to the magnetic interactions between particles.     

Steam-activated carbons from a bituminous coal in a continuous multistage fluidized bed pilot plant

A vertical three-stage fluidized bed pilot plant, with downcomers, was designed and built in order to study the continuous process of the production of activated carbons from a high-volatile bituminous coal from the Puertollano basin (Spain), by steam activation. The pilot plant can operate with a production of up to 40 kg per day. Very good activated carbons were produced at the selected operating conditions. The effect of the following operating conditions on the reactivity and adsorption characteristics of the activated carbons was analyzed: (1) carbonization conditions (one- and two-step activation), (2) activation temperature (800–850 °C), and (3) steam gas velocity (1.5–3 times the minimum fluidization velocity). Carbonization conditions considerably affect the reactivity of the chars obtained; the faster the carbonization process, the higher the reactivity. Nevertheless, the effect of this variable on the development of porosity is not very relevant, and consequently the direct activation process is an attractive alternative to the two-step (carbonization and activation) process. On the other hand, both temperature and steam flow rate (affecting the reaction rate) have a marked effect on the development of porosity.     

Effects of vinyltrimethoxy silane on mechanical properties and morphology of polypropylene‐woodflour composites

The effects of composition and interface modification on the tensile properties and the impact resistance of different woodflour/polypropylene composites (WPC) were studied. The woodflour was treated with vinyltrimethoxy silane as a coupling agent, and its effect on the WPC properties was examined. In addition, the tensile data were fitted with several semiempirical models to clarify the mechanical behavior of the composites. The Pukánszky parameters obtained from the fit of the tensile strength data revealed that the distribution of the filler was more homogeneous in the composites containing silane and that interaction between components was improved. The impact strength was maximal for the composites containing 30% of silane‐treated woodflour. Morphological analysis by SEM revealed that the woodflour tended to form agglomerates when present in relatively high amounts in the formulations. For the silane‐treated composites, the dispersion of the filler into the polypropylene (PP) matrix improved, although surface treatment blocked the inclusion of PP into the wood cells. This probably decreased the elastic moduli, even when the filler‐matrix interaction was improved. The beneficial effects of the coupling agent on the WPC properties were greater in the materials containing a relatively low amount of filler (up to 30%); the effectiveness of 0.5% and 1% organosilane were very similar, demonstrating the effectiveness of the coupling agent. POLYM. ENG. SCI., 2009. © 2008 Society of Plastics Engineers     

Mortality due to lung, laryngeal and bladder cancer in towns lying in the vicinity of combustion installations

Background

Installations that burn fossil fuels to generate power may represent a health problem due to the toxic substances which they release into the environment.

Objectives

To investigate whether there might be excess mortality due to tumors of lung, larynx and bladder in the population residing near Spanish combustion installations included in the European Pollutant Emission Register.

Methods

Ecologic study designed to model sex-specific standardized mortality ratios for the above three tumors in Spanish towns, over the period 1994-2003. Population exposure to pollution was estimated on the basis of distance from town of residence to pollution source. Using mixed Poisson regression models, we analyzed: risk of dying from cancer in a 5-kilometer zone around installations that commenced operations before 1990; effect of type of fuel used; and risk gradient within a 50-kilometer radius of such installations.

Results

Excess mortality (relative risk, 95% confidence interval) was detected in the vicinity of pre-1990 installations for lung cancer (1.066, 1.041-1.091 in the overall population; 1.084, 1.057-1.111 in men), and laryngeal cancer among men (1.067, 0.992-1.148). Lung cancer displayed excess mortality for all types of fuel used, whereas in laryngeal and bladder cancer, the excess was associated with coal-fired industries. There was a risk gradient effect in the proximity of a number of installations.

Conclusions

Our results could support the hypothesis of an association between risk of lung, laryngeal and bladder cancer mortality and proximity to Spanish combustion installations.     

Novel Self‐Reinforced Films Based on Poly (3‐Hydroxybutyrate‐Co‐3‐Hydroxyvalerate) (PHBV) and PHBV Microparticles

Biodegradable self‐reinforced films of poly (3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV) and PHBV microparticles were prepared through the solvent casting method (srPHBV). Differential scanning calorimetry (DSC), wide angle X‐ray scattering (WAXS) and polarized optical microscopy results confirmed the nucleating effect of PHBV microparticles. WAXS proved that diffractograms of PHBV and srPHBV‐6 films at room temperature contain the main characteristic diffraction peaks of an orthorhombic α‐type crystalline structure. Small angle X‐ray scattering (SAXS) showed a similar decrement rate of long spacing in PHBV and srPHBV films. SAXS/WAXS data revealed that when the amount of filler was increased, lamellae thickness grew. Transmission electron microscopy images illustrated well filler dispersion in the srPHBV films. Scanning electron microscopy results exhibited a significant reduction in porosity for srPHBV films once the PHBV microparticles were added. Atomic force microscopy analysis showed higher surface roughness after filler incorporation. Samples of srPHBV films showed higher barrier properties against water vapor, oxygen, and carbon dioxide. Combined properties of srPHBV films revealed the possibility of being suitable candidates for food packaging applications. POLYM. ENG. SCI., 59:E120–E128, 2019. © 2018 Society of Plastics Engineers     

Metataxonomic and immunological analysis of milk from ewes with or without a history of mastitis

Mastitis is a highly prevalent condition that has a great impact on milk production and animal welfare, and often requires substantial management efforts. For this reason, it is generally considered an important threat to the dairy industry. Many microbial, host, and environmental factors can protect against, predispose to, or influence the development of mastitis. The objective of this work was to characterize the milk microbiota of Manchega ewes, and to compare samples from animals with and without a history of mastitis. We analyzed milk samples from 36 ewes belonging to 2 different farms (18 ewes from each farm) using culture-dependent and culture-independent techniques. We also analyzed several immune compounds to investigate associations of mastitis with 3 main variables: farm; history of mastitis or no mastitis; and parity number. Both culture-dependent and culture-independent techniques showed that ewe milk harbored a site-specific complex microbiota and microbiome. Staphylococcus epidermidis was the main species driving the difference between farm A (where it was the dominant species) and B (where it was not). In contrast, samples from farm B were characterized by the presence of a wide spectrum of other coagulase-negative staphylococci. Some of these species have already been associated with subclinical intramammary infections in ruminants. Of the 10 immune compounds assayed in this study, 3 were related to a history of mastitis [IL-8, IFN-γ, and IFN-gamma-induced protein 10 (IP-10)]. Increases in IL-8 concentrations in milk seemed to be a feature of subclinical mastitis in sheep, and in this study, this immune factor was detected only in samples from ewes with some episodes of mastitis and from the group with the highest somatic cell count. We also observed a positive correlation between the samples with the highest somatic cell count and IFN-γ and IP-10 levels. Our results suggest that these 3 compounds could be used as biomarkers for the negative selection of mastitis-prone animals, particularly when somatic cell count is very high.     

Latent communities of digital publications: The role of editors,followers, and advertisers

This research explores how digital publications may be turned into something more than just a meeting point for people who are seeking information and may become a latent community. The paper proposes that the network of editors, followers, and advertisers of digital publications determine the user sense of community towards the publication. While the pattern of connections among editors and followers reinforces the sense of community, advertisers act as intruders who weaken the feasibility of building a community. Data were collected from followers of digital publications. The dynamics of the sense of community is described as a process in which informational value and identification are essential to nurturing readers’ soft or hard commitment. Findings indicate that the strong ties between editors and followers as well as the diversity positively impacts on informational value and identification, whereas advertising intrusiveness diminishes the informational value.     

Relationship between Proinflammatory and Antioxidant Proteins with the Severity of Cardiovascular Disease in Type 2 Diabetes Mellitus

Type 2 diabetes mellitus patients are at significant risk of cardiovascular disease, however, the pathophysiology of these complications is complex and incompletely known in this population. The aim of this study was to compare the serum proteome of patients with type 2 diabetes mellitus presenting or not presenting cardiovascular disease with non-diabetic subjects to find essential proteins related to these cardiovascular complications. This cross-sectional study compares the serum proteome by a combination of protein depletion with 2D-DIGE (2-dimension Difference Gel Electrophoresis) methodology. The proteins differentially expressed were identified by MALDI TOF/TOF (Matrix-assisted laser desorption/ionization and Time-Of-Flight ion detector) or LC-MS/MS (Liquid Chromatography coupled to Mass-Mass Spectrometry). Type 2 diabetes mellitus patients with cardiovascular disease showed higher expression of plasma retinol binding protein and glutathione peroxidase-3 compared to those without cardiovascular disease and non-diabetic controls. These results show that proteins related to the inflammatory and redox state appear to play an important role in the pathogenesis of the cardiovascular disease in the type 2 diabetes mellitus patients.