Polyhydroxyalkanoates (PHAs) are the ideal candidates for the substitution of the conventional plastics, as they present similar properties with them, but are also environmentally friendly. Regardless of their benefits, these biopolymers still face challenges today, due to their high market price, which is related to the raw material selected for their production. The utilization of low cost and readily available substrates - like organic wastes - for PHA production is a promising solution, which can decrease the total biopolymer production cost. However, PHA products from waste-derived materials need to have a consistent quality. This currently remains a challenge. The last years, PHA production from organic wastes, like food waste, has acquired growing attention. This work reviews the literature of the last decade on the use of household food waste as feedstock for PHA production. Household food waste has been divided in three categories: composite food waste, spent oils and spent coffee grounds. Both pure and mixed microbial cultures have been employed. The review focuses on the feedstock’s and the culture’s pre-treatment methods, the biopolymer’s production and the purification of the final product. It also refers to the PHA content obtained in each scientific work. Household food waste has proven to be a good substrate, especially when combined with pure microbial cultures, like Cupriavidus necator that resulted in PHA accumulation from around 37% to 90%. This scientific work also provides informations concerning PHA applications, industrial production and market prices.

Abbreviations

®, registered trademark symbol; ATCC, American Type Culture Collection; FFW, fermented food waste; FWC, composite food waste; GC, gas chromatography; GC-MS, gas chromatography-mass spectrometry; HA, hydroxyalkanoates; HDPE, high density polyethylene; HPLC, high performance liquid chromatography; HRT, hydraulic retention time; LB, Luria-Bertani; LDPE, low-density polyethylene; MM, mineral salt medium; MMC, mixed microbial cultures; MSB, minimal salt basal medium; OLR, organic loading rate; PHAs, polyhydroxyalkanoates; PHB, poly(3-hydroxybutyrate); P(HB-HV), poly(3-hydroxybutyrate-co-3-hydroxyvalerate); PHO, poly(3-hydroxy-octanoate); PLA, poly (lactic-acid); PP, polypropylene; SBRs, sequencing batch reactors; SCG, spent coffee grounds; SEC, size-exclusion chromatography; SRT,

sludge retention time; TM, unregistered trademark symbol; TSA, tryptone soya agar; TSB, tryptone soya broth; UASB, upflow anaerobic sludge blanket; UCO, used cooking oil; UFW, unfermented food waste; VFAs, volatile fatty acids; WCO, waste cooking oil

With widespread use of pre-exercise stretching methods across sport and exercise, recent studies have questioned the effectiveness of such methods (Kay & Blazevich 2012; Cramer et al., 2005; Curry, Chengkalath, Crouch, Romance, & Manns, 2009). The purpose of this study was to examine how the relationship between pennation angle, proprioception, and muscle power are influenced by a static stretching protocol. Participants (n = 17) from a southeastern university in the United States consented to participate and were divided into an experimental group (n = 12) and control group (n = 5). The experimental group engaged in static stretched by placing the right foot on an incline board and maximally dorsiflexing the ankle joint while keeping the bottom of their foot flush with the board’s surface and the

knee fully extended. The control group remained seated for the same amount of time and did not engage in stretching. Both groups were measured for vertical jump using the Vertec force plate, electrical activity of the gastrocnemius via the Terason ultrasound machine, and proprioception of the ankle joint via the Biodex 2 dynamometer pre- and post- stretching and control protocols. Results indicated that static stretching resulted in a decrease in muscle power without change of proprioception or electrical-mechanical delay while accompanied by an increase in pennation angle. The increase in pennation angle may the reason why static stretch resulted in a reduction in muscle power. The results are discussed in regard to previous research and future practical application.

L’objectif de cette étude est de réaliser un biocapteur micro-onde miniaturisé afin d’effectuer des caractérisations diélectriques de tissus biologiques, et plus particulièrement de plaques athéromateuses présentes dans les tissus artériels. Le principe de ce capteur est basé surun circuit résonnant de type CSRR fonctionnant à la fréquence de 2.3 GHz. Une modélisation électromagnétique et une caractérisation

expérimentale ont permis de valider le modèle électrique équivalent développé avec une très bonne précision. Un étalonnage de ce capteur sera aussi effectué à l’aide de matériaux connus et les résultats obtenus comparés à ceux donnés par d’autres techniques de caractérisation.

The paper states that the insertions of Polo-like Kinase 4 (Plk4) into the centrosome forms the basis for construction of new centrioles during the time when a cell is about to divide (mitosis). If the inserted amount of Plk4 is too little, the cell will die instead of dividing. Alternatively, excessive Plk4 insertion can produce extra centrioles ultimately leading to tumorigenesis and cancer. Therefore, in order for normal cell division and duplication to occur, the amount of Plk4 inserted needs to be carefully controlled.

The paper also provides a review of centriole construction and geometry as a basis for Plk4 study. The paper is therefore self-contained: that is, a general review ending with a focus on Plk4.