Design, manufacturing and testing of a rotorcraft access panel door from recycled carbon fiber reinforced polyphenylenesulfide

An integrally-stiffened access panel for a rotorcraft is selected for detail design, testing and actual flight to demonstrate a novel recycling route for thermoplastic composites. The design, development and validation followed the ‘Building Block approach’. The used material is post-industrial carbon fiber reinforced polyphenylene sulfide waste. This material originates from thermoplastic components of the very same rotorcraft as the panel will be mounted on, improving traceability, logistics and fixing supply and demand. Material data have been gathered from mechanical tests and used to predict the panels strength and stiffness. A critical design detail was selected and tested for validation. This section was included in a manufacturing demo, along with other integrated design features, enabling testing the processability. The final panel design was successfully produced and tested on component level. The re-manufacturing process includes simultaneously applied heat and low-shear mixing, followed by compression molding in an isothermal mold. This offers the possibility to retain long fibers and therefore high mechanical properties at short cycle times. In comparison to the current carbon/epoxy solution, the resulting product is lighter, significantly more cost-effective and made of recycled material (fiber and matrix). The prototype panel is targeted for flight testing on the rotorcraft in 2019.Dutch Organization of Applied Research – SIA, projeto SIA-RAAK 2014-01-72PR

Athletes treated for inguinal-related groin pain by endoscopic totally extraperitoneal (TEP) repair:long-term benefits of a prospective cohort

Purpose: Inguinal-related groin pain (IRGP) in athletes is a multifactorial condition, posing a therapeutic challenge. If conservative treatment fails, totally extraperitoneal (TEP) repair is effective in pain relief. Because there are only few long-term follow-up results available, this study was designed to evaluate effectiveness of TEP repair in IRGP-patients years after the initial procedure. Methods: Patients enrolled in the original, prospective cohort study (TEP-ID-study) were subjected to two telephone questionnaires. The TEP-ID-study demonstrated favorable outcomes after TEP repair for IRGP-patients after a median follow-up of 19 months. The questionnaires in the current study assessed different aspects, including, but not limited to pain, recurrence, new groin-related symptoms and physical functioning measured by the Copenhagen Hip and Groin Outcome Score (HAGOS). The primary outcome was pain during exercise on the numeric rating scale (NRS) at very long-term follow-up.Results: Out of 32 male participants in the TEP-ID-study, 28 patients (88%) were available with a median follow-up of 83 months (range: 69–95). Seventy-five percent of athletes were pain free during exercise (p &lt; 0.001). At 83 months follow-up, a median NRS of 0 was observed during exercise (IQR 0–2), which was significantly lower compared to earlier scores (p &lt;0.01). Ten patients (36%) mentioned subjective recurrence of complaints, however, physical functioning improved on all HAGOS subscales (p &lt;0.05).Conclusion:This study demonstrates the safety and effectivity of TEP repair in a prospective cohort of IRGP-athletes, for whom conservative treatment had failed, with a follow-up period of over 80 months.</p

Highly Parallel and Short-Acting Amplification with Locus-Specific Primers to Detect Single Nucleotide Polymorphisms by the DigiTag2 Assay

The DigiTag2 assay enables analysis of a set of 96 SNPs using Kapa 2GFast HotStart DNA polymerase with a new protocol that has a total running time of about 7 hours, which is 6 hours shorter than the previous protocol. Quality parameters (conversion rate, call rate, reproducibility and concordance) were at the same levels as when genotype calls were acquired using the previous protocol. Multiplex PCR with 192 pairs of locus-specific primers was available for target preparation in the DigiTag2 assay without the optimization of reaction conditions, and quality parameters had the same levels as those acquired with 96-plex PCR. The locus-specific primers were able to achieve sufficient (concentration of target amplicon ≥5 nM) and specific (concentration of unexpected amplicons <2 nM) amplification within 2 hours, were also able to achieve detectable amplifications even when working in a 96-plex or 192-plex form. The improved DigiTag2 assay will be an efficient platform for screening an intermediate number of SNPs (tens to hundreds of sites) in the replication analysis after genome-wide association study. Moreover, highly parallel and short-acting amplification with locus-specific primers may thus facilitate widespread application to other PCR-based assays

Targeted resequencing of candidate genes using selector probes

Targeted genome enrichment is a powerful tool for making use of the massive throughput of novel DNA-sequencing instruments. We herein present a simple and scalable protocol for multiplex amplification of target regions based on the Selector technique. The updated version exhibits improved coverage and compatibility with next-generation-sequencing (NGS) library-construction procedures for shotgun sequencing with NGS platforms. To demonstrate the performance of the technique, all 501 exons from 28 genes frequently involved in cancer were enriched for and sequenced in specimens derived from cell lines and tumor biopsies. DNA from both fresh frozen and formalin-fixed paraffin-embedded biopsies were analyzed and 94% specificity and 98% coverage of the targeted region was achieved. Reproducibility between replicates was high (R2 = 0, 98) and readily enabled detection of copy-number variations. The procedure can be carried out in <24 h and does not require any dedicated instrumentation

Characterization of long and stable de novo single alpha-helix domains provides novel insight into their stability

Naturally-occurring single α-helices (SAHs), are rich in Arg (R), Glu (E) and Lys (K) residues, and stabilized by multiple salt bridges. Understanding how salt bridges promote their stability is challenging as SAHs are long and their sequences highly variable. Thus, we designed and tested simple de novo 98-residue polypeptides containing 7-residue repeats (AEEEXXX, where X is K or R) expected to promote salt-bridge formation between Glu and Lys/Arg. Lys-rich sequences (EK3 (AEEEKKK) and EK2R1 (AEEEKRK)) both form SAHs, of which EK2R1 is more helical and thermo-stable suggesting Arg increases stability. Substituting Lys with Arg (or vice versa) in the naturally-occurring myosin-6 SAH similarly increased (or decreased) its stability. However, Arg-rich de novo sequences (ER3 (AEEERRR) and EK1R2 (AEEEKRR)) aggregated. Combining a PDB analysis with molecular modelling provides a rational explanation, demonstrating that Glu and Arg form salt bridges more commonly, utilize a wider range of rotamer conformations, and are more dynamic than Glu–Lys. This promiscuous nature of Arg helps explain the increased propensity of de novo Arg-rich SAHs to aggregate. Importantly, the specific K:R ratio is likely to be important in determining helical stability in de-novo and naturally-occurring polypeptides, giving new insight into how single α-helices are stabilized

Erratum to: Mutation screening in 86 known X-linked mental retardation genes by droplet-based multiplex PCR and massive parallel sequencing

Item does not contain fulltext[This corrects the article DOI: 10.1007/s11568-010-9137-y.].1 december 200