The Synergistic Effect of Carbon Black/Carbon Nanotube Hybrid Fillers on the Physical and Mechanical Properties of EPDM Composites after Exposure to High-Pressure Hydrogen Gas.

This study investigated the synergistic effect of carbon black/multi-wall carbon nanotube (CB/MWCNT) hybrid fillers on the physical and mechanical properties of Ethylene propylene diene rubber (EPDM) composites after exposure to high-pressure hydrogen gas. The EPDM/CB/CNT hybrid composites were prepared by using the EPDM/MWCNT master batch (MB) with 10 phr CNTs to enhance the dispersion of CNTs in hybrid composites. The investigation included a detailed analysis of cure characteristics, crosslink density, Payne effect, mechanical properties, and hydrogen permeation properties. After exposure to 96.3 MPa hydrogen gas, the hydrogen uptake and the change in volume and mechanical properties of the composites were assessed. We found that as the MWCNT volume fraction in fillers increased, the crosslink density, filler-filler interaction, and modulus of hybrid composites increased. The hydrogen uptake and the solubility of the composites decreased with an increasing MWCNT volume fraction in fillers. Moreover, after exposure to hydrogen gas, the change in volume and mechanical properties exhibited a diminishing trend with a higher MWCNT volume fraction. We conclude that the hybridization of CB and CNTs formed strong filler-filler networks in hybrid composites, consequently reinforcing the EPDM composites and enhancing the barrier properties of hydrogen gas.

The Effect of Polyamide 11 on the Thermal Stability and Light Transmittance of Silicone-Based Thermoplastic Vulcanizates.

The effect of polyamide 11 (PA11) on the thermal stability and light transmittance properties of silicone-based thermoplastic vulcanizates (TPVs) has been investigated. The blends were prepared through a dynamic vulcanization process by adding 15, 30, and 45 wt% PA11 to the silicon-based TPVs, respectively. The effect of PA11 on the dispersion of silicone rubber in the TPVs after dynamic vulcanization was characterized by a scanning electron microscope (SEM), the thermal stability of the compounds was evaluated through the changes in mechanical performance in the thermo-oxidative aging process, and the light transmittance of TPVs was measured by a haze meter. The results showed that adding PA11 to silicone-based TPVs caused a decrease in the size of the silicone rubber particles after dynamic vulcanization, resulting in improved dispersion. Due to this, by increasing the compatibility between the segments through silicone's effective dispersion, the amount of light absorption was reduced, and the amount of light transmittance was increased. Finally, according to the results of the thermal aging test, it was found that TPVs with 30 and 45 wt% PA11, respectively, showed outstanding thermal resistance after aging at 160 °C and 168 h and did not melt down.

Efficacy of Minimally Invasive Oblique Lumbar Interbody Fusion Using Polyetheretherketone Cages for Lumbar Pyogenic Spondylodiscitis Treatment.

(1) Background: This study evaluated the efficacy and safety of a minimally invasive oblique lumbar interbody fusion (OLIF) using polyetheretherketone (PEEK) cages for the treatment of lumbar pyogenic spondylodiscitis. (2) Methods: Fifty-one patients with single-level lumbar pyogenic spondylodiscitis were included in the study. Patients were divided into two groups: anterior lumbar interbody fusion with a tri-cortical iliac bone graft (ALIF+ tri-cortical iliac bone graft) (n = 28) and OLIF using PEEK cages with an autologous bone graft (OLIF+ PEEK cages) (n = 23). Perioperative radiographic parameters, complications, and clinical outcomes in both groups were analyzed and compared. (3) Results: The postoperative and final follow-up LL (lumbar lordosis) and RL (regional lordosis) were improved in both groups (p < 0.001). But, compared with the ALIF group, the OLIF group had more improvement of the RL. The operation time was 79 min for the OLIF group and 101 min for the ALIF group (p < 0.05). The intraoperative blood loss was 92 mL for the OLIF group and 114 mL for the ALIF group (p < 0.05). Significant clinical improvement was observed in visual analogue scale scores for the back and Oswestry Disability Index in both groups (p < 0.001). There was no recurrence of infection. (4) Conclusions: Compared with the ALIF group, the OLIF group had more improvement in radiographic and clinical outcomes. Thus, OLIF using PEEK cages with an autologous bone graft could be proposed for the surgical treatment of lumbar pyogenic spondylodiscitis.

Influence of Carbon Black and Silica Fillers with Different Concentrations on Dielectric Relaxation in Nitrile Butadiene Rubber Investigated by Impedance Spectroscopy.

In neat nitrile butadiene rubber (NBR), three relaxation processes were identified by impedance spectroscopy: α and α' processes and the conduction contribution. We investigated the effects of different carbon black (CB) and silica fillers with varying filler content on the dielectric relaxations in NBR by employing a modified dispersion analysis program that deconvolutes the corresponding processes. The central frequency for the α' process with increasing high abrasion furnace (HAF) CB filler was gradually upshifted at room temperature, while the addition of silica led to a gradual downshift of the center frequency. The activation energy behavior for the α' process was different from that for the central frequency. The use of HAF CB led to a rapid increase in DC conductivity, resulting from percolation. The activation energy for the DC conductivity of NBRs with HAF CB decreased with increasing filler, which is consistent with that reported in different groups.

Complaints addressed by regulatory authorities in drug advertising targeted at consumers: Cases across three, different countries.

BACKGROUND: Misleading advertisements can affect behavior of both consumers and prescribers and may lead to inappropriate use of medications. OBJECTIVE: To analyze the complaints upheld by regulatory authorities in the United Kingdom, Canada, and Australia regarding pharmaceutical advertising directed at consumers. METHODS: Complaints addressed between January 2014 and June 2017 were retrieved from the websites of regulatory authorities. Complaints addressed by self-regulatory bodies were not included due to the poor availability of data. RESULTS: Sixty complaints, 374 complaints, and 223 complaints from the United Kingdom, Canada, and Australia, respectively, were analyzed. In the United Kingdom, the most frequent type of violation was advertising of prescription drugs (70.5%); most of these violations involved botulinum toxin. In Canada, advertising on online media was more likely to be associated with prescription drugs than that on traditional media (P < 0.001). In Australia, advertising of prescription drugs accounted for less than 10% of complaints, but all were associated with online media. CONCLUSIONS: In countries where direct-to-consumer advertising of prescription drugs is prohibited, regulatory authorities may need to devise further strategies to safeguard the public as this is an unresolved issue and is predicted to become more problematic with the increased use of online media.

In vivo commitment and functional tissue regeneration using human embryonic stem cell-derived mesenchymal cells.

Development of clinically relevant regenerative medicine therapies using human embryonic stem cells (hESCs) requires production of a simple and readily expandable cell population that can be directed to form functional 3D tissue in an in vivo environment. We describe an efficient derivation method and characterization of mesenchymal stem cells (MSCs) from hESCs (hESCd-MSCs) that have multilineage differentiation potential and are capable of producing fat, cartilage, and bone in vitro. Furthermore, we highlight their in vivo survival and commitment to the chondrogenic lineage in a microenvironment comprising chondrocyte-secreted morphogenetic factors and hydrogels. Normal cartilage architecture was established in rat osteochondral defects after treatment with chondrogenically-committed hESCd-MSCs. In view of the limited available cell sources for tissue engineering applications, these embryonic-derived cells show significant potential in musculoskeletal tissue regeneration applications.