A flocculant based on cashew gum (CG) grafted with polyacrylamide (PAM) was synthesized using potassium persulfate as the chemical initiator and ultrasound energy. The intrinsic viscosity, hydrodynamic radius, and grafting efficiency of the grafted copolymers (CG-g-PAM) were investigated at different monomer and initiator concentrations. The CG-g-PAM copolymers were evaluated in kaolin suspension and river water by using jar test procedure comparatively to a commercial flocculant (Flonex-9045). Ultrasonication resulted in reduced reaction time and high grafting efficiency. The reaction gel point was reached within 10 min and the grafting efficiency was dependent on the acrylamide concentration. The grafted copolymer CG-g-PAM-15 285 obtained with 0.285 mmol of initiator showed higher hydrodynamic radius, with flocculation efficacy of 96% comparable with the flocculant Flonex-9045.

Here we investigate the behavior of controlled‐release systems based on poly(hydroxybutyrate) (PHB) to propose an actuation mechanism in a designed environment. Two formulations were produced employing 5% pure NPK fertilizer or 30% of bentonite nanoparticles (Bent) previously modified with NPK. The polymeric composites were obtained by melt processing and their thermal properties evaluated. The release of active compounds was evaluated by conductometric analysis in aqueous solutions at different pHs for 30 days, and the results were modulated by the Korsmeyer‐Peppas model. Also, the systems were evaluated for their biodegradation characteristics using different soil types to generate a decomposition profile. In general, the systems showed a good release control, with 40% and 50% of fertilizer being released in 30 days, depending on the conditions and type of polymeric composite employed. The model indicated a linear release of active compounds in the first 30 days, according to the Fick diffusion. Additionally, the compounds were relatively stable in the first 30 days when exposed to biodegradation, being degraded faster speed after this. The efficiency and applicability of the systems were confirmed by the germination tests, which showed that both systems containing NPK favored plant growth, while the system in which the active agents had been previously incorporated into nanoparticles provided a reduction in the waste of agrochemicals. Thus, a novel mechanism of action for polymeric controlled release systems based on thermoplastic biopolymers was determined, supporting more efficient industrial processes.

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This experiment was conducted to determine the effect of earlier weaning in addition to biocholine supplementation on age at puberty of Brangus heifers. Brangus calves were randomized and divided into three weaning ages groups, at 30 (Hyper-early weaning; HW), 75 (Early weaning; EW) and 180 days (Conventional weaning; CW). Then, calves were supplemented using the additive Biocholine (BIO) or not (CON). Animals were subjected to puberty induction and transrectal ultrasonography was performed to assess the ovarian activity and the presence of corpus luteum to determine heifer puberty. We also evaluated the body weight (BW; Kg), hip height (HH; cm), thoracic perimeter (TP; cm) and BW:HH ratio during the experimental period. BIO group showed higher ADG (>226g/day) when the animals were exposed to ryegrass pasture compared to CON (P < 0.05). We observed an interaction between weaning x biocholine and CW-BIO heifers showed greater HH more compared to CW-CON (P < 0.05). Overall, animals that have reached puberty at day 8 after puberty induction showed 331.0±23.14kg BW, 122.0±2.58cm HH and 165.4±3.45cm TP and 2.7±0.14 BW:HH. At the time of ovulation detection, the heifers from the HW group had 32.1kg BW, 3.93cm HH and 0.18cm BW:HH greater compared to CW (P < 0.05). The BIO supplementation together with ryegrass pasture, led to an increase in ADG weight throughout the evaluated period. We concluded that HW heifers showed an adequate body development throughout the experimental period until puberty appearance at the same age as others weaned groups.