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Processing of end-of-life tyres (ELT) produces polymer fibres (PFELT) as a by-product. PFELT currently presents a challenge to the recycling industry, due to the increasing numbers of ELT and lack of alternatives for the re-use of this material. The object of this investigation was to propose an alternative for re-using PFELT, in order to improve the performance properties of hot mix asphalt (HMA). This study enabled us to understand the relation between the addition of polymer fibre to the aggregate-binder matrix of the HMA in depth, as well as its effects on the mechanical properties of the resulting asphalt mix. To do this, we first made a physical and chemical characterization of the PFELT (TGA, SEM, polarized light, and fluorescence microscopy), establishing a modification methodology using two asphalt binders (CA-24 and CA-14) and three PFELT contents (0.1%, 0.3%, and 0.5%). The HMA was designed using the Marshall method. The mechanical performance of the HMA was evaluated in a range of operating temperatures, from −10 °C to 50 °C, observing the following properties: (1) resistance to thermal cracking; (2) stiffness modulus; (3) indirect tensile strength; and (4) resistance to permanent deformation. The results show that the addition of 0.3% and 0.5% of PFELT to the asphalt binder significantly improved the mechanical performance properties of the mixes studied, with a greater effect at high operating temperatures; the resistance to permanent deformation increased by more than 30%.

Today, an important part of paved surfaces in the world uses asphalt mixtures. This practice increases the use of aggregates and fossil fuels, the availability of which is limited. Most of the studies referring to asphalt mixtures reported and compared the mechanical performances without detailing the environmental impacts of the different technologies proposed. The objective of this study was to present and compare through a life cycle assessment using a “cradle-to-gate” approach of different types of asphalt mixtures designed for the same performance, hot mix asphalt (HMA) as a control sample, and warm mix asphalt (WMA) using natural zeolite, Evotherm® and reclaimed asphalt material (RAP) in different proportions. The analysis was performed using SimaPro 9 software, using the ReCiPe method version 1.11. For the comparison of the environmental impacts, 1 ton of asphalt mixture was used as a functional unit. The most relevant results show that the use of natural zeolite or Evotherm® helps to reduce environmental impacts. In the global warming impact category, the decrease between the standard HMA and a mix with RAP and natural zeolite was 8%, while in the fossil fuel depletion, the decrease was 13%.

Several authors have demonstrated improvements in the mechanical performance of asphalt mixes by including the use of fibers. However, it has also been reported that environmental assessments must address fiber use in asphalt mixes from the point of view of sustainability. In this study, a life cycle assessment is used to compare the use of four different fibers (fiberglass, polyester fiber, aramid fiber, and cellulose fiber) commonly used in hot mix asphalt (HMA) and stone mastic asphalt (SMA) mixes. Additionally, the use of textile fibers from end-of-life tires (FiTyre) is included in the comparison. The results show that in the five selected impact categories (climate change, terrestrial acidification, human toxicity, particulate matter emissions, and the exhaustion of nonrenewable fossil fuels), the use of FiTyre and cellulose fibers is more advantageous than existing traditional fibers (fiberglass, polyester fiber, and aramid fiber).

Optical Coherence Tomography (OCT) is a noninvasive, high-speed, high-resolution imaging technology based in the Michaelson interferometry. A near-infrared light beam is used to register the intensity variations for the light backscattered on each sample layer. Due to the high repeatability on corneal measurements, spectral domain OCT (SD-OCT) is the gold standard when talking about in vivo, non-invasive anterior segment imaging. Changes in the morphology of various ocular surfaces such as the cornea, conjunctiva, limbus or tear film with soft (SCL), rigid, corneal or scleral lens (SL) wear can be described by OCT measurements. For instance, evaluation of the corneoscleral region is essential on SL fitting. For orthokeratology lenses central epithelial thinning and peripheral thickening and their regression could be quantified with OCT after Ortho-K lens wear. Blood vessel compression on the landing zone as well as vault thickness and fluid reservoir (FR) turbidity could be imaged with OCT. Tear film evaluation on contact lens wearers is essential because its use could lead to variations on the biochemical components in tears. Changes in tear meniscus dynamics and several parameters such as volume (TMV), tear meniscus height (HMT) and turbidity could be determined with OCT and positively correlated with the instillation of different ophthalmic solutions with Non-Invasive Break Up Time (NIBUT) and Schirmer test values. This manuscript shows the increasing applicability of OCT technology for the in vivo characterization of contact lens fitting and interaction with the ocular surface in a faster, safer and non-invasive way. Future research will still allow exploring OCT imaging to its full potential in contact lens practice, as there is still a significant amount of information contained in the images that are not yet easy to extract, analyze and give clinical value.

OBJECTIVE: Our aim was to report the recent changes in diagnosis and management of TSH-secreting pituitary adenomas. METHODS: We retrieved 43 consecutive patients with TSH-secreting pituitary tumors (23 male and 20 female) among 4400 pituitary adenomas followed between 1976 and 2001 in six Belgian and French centers. RESULTS: TSH was elevated in 18/43 and alpha subunit in 13/32 patients. In patients with intact thyroid (n=30), mean free tri-iodothyronine was 13.1 pmol/l (range 3.5-23) and mean free thyroxine was 38.4 pmol/l (range 10.2-62.7). Hyperprolactinemia and acromegaly were associated in 9/43 and 8/43 cases. The number of associated hypersecretions was higher in macroadenomas than in microadenomas (Chi square = 11.2, P

Colloid cysts of the third ventricle are rare, benign cysts of endodermal origin. Between 1989 and 1999, eight patients with this lesion (five females, three males), with a mean age of 40.5 years (range 20-54), were identified out of 1354 operated for tumours of the central nervous system. Among the eight, two were familial. They were half sisters 38 and 28 years-old, who were diagnosed to have colloid cysts of the third ventricle on CT scanning. Transcortical excision yielded 10 and 15 mm sized colloid cysts, respectively. Moreover, both sisters developed a multinodular goiter associated with these congenital tumours. The second sibling developed hyperprolactinemia associated with macroprolactinemia. Pregnancy was only possible after bromocriptine treatment. These cases provide further evidences that colloid cysts probably have an autosomic recessive pattern of inheritance with variable penetrance.