The Effect of Porosity Density and Configuration in Composite Materials on the Ultrasonic Waveform

Current practice is to accept or reject composite parts based upon ultrasonic C-scan results. Normally, this is based only on ultrasonic attenuation data. However, attenuation data alone does not account for variations in porosity distribution or type, and ignores the fact that other variables can influence attenuation besides porosity. This work was directed at determining additional parameters which can be used to define the defect structure in a composite

Correlation of Early Outcomes and Intradiscal Interleukin-6 Expression in Lumbar Fusion Patients.

OBJECTIVE: To determine if there is correlation between intradiscal levels of interleukin-6 (IL-6) and early outcome measures in patients undergoing lumbar fusion for painful disc degeneration. METHODS: Intervertebral disc tissue was separated into annulus fibrosus/nucleus pulposus and cultured separately in vitro in serum-free medium (Opti-MEM). Conditioned media was collected after 48 hours. The concentration of IL-6 was quantified using enzyme-linked immunosorbent assay. Pearson correlation coefficients quantified relationships between IL-6 levels and pre- and postoperative visual analogue scale (VAS) back pain and Oswestry Disability Index (ODI), as well as change in VAS/ODI. RESULTS: Sixteen discs were harvested from 9 patients undergoing anterior lumbar interbody fusion (mean age, 47.4 years; range, 21-70 years). Mean preoperative and 6-month postoperative VAS were 8.1 and 3.7, respectively. Mean preoperative and postoperative ODI were 56.2 and 25.6, respectively. There were significant positive correlations between IL-6 expression and postoperative VAS (ρ = 0.38, p = 0.048) and ODI (ρ = 0.44, p = 0.02). No significant correlations were found between intradiscal IL-6 expression and preoperative VAS (ρ = -0.12, p = 0.54). Trends were seen associating IL-6 expression and change in VAS/ODI (ρ = -0.35 p = 0.067; ρ = -0.34, p = 0.08, respectively). A trend associated IL-6 and preoperative ODI (ρ = 0.36, p = 0.063). CONCLUSION: The direct association between IL-6 expression and VAS/ODI suggests patients with elevated intradiscal cytokine expression may have worse early outcomes than those with lower expression of IL-6 after surgery for symptomatic disc degeneration

Paper Session II-C - Command and Control Through Space-Based Systems

A new space-based command and control concept is presented that combines a ground station in conjunction with satellites utilizing modern RF communications technology. By using current satellites such as TDRSS, GPS or the proposed LEO/MEO commercial constellations, the command system of the future will provide a reliable and highly redundant replacement for the current command system that requires as many as seven UHF transmitter sites along the various launch vehiclesÕ flight paths. This space-based command system requires a look at new technologies to provide innovative ways to transmit secure and jam resistant messages from the launch operations center. These messages would then be relayed through a satellite to the launch vehicle and back to the operations center for confirmation. This new command system must conform to Range Safety guidelines in terms of minimal propagation time, communication security, maximum reliability and design efficiency to ensure that no single point of failure will deny the capability to terminate or result in the inadvertent termination of a launch vehicle or payload

The Effect of Porosity Density and Configuration in Composite Materials on the Ultrasonic Waveform

Current practice is to accept or reject composite parts based upon ultrasonic C-scan results. Normally, this is based only on ultrasonic attenuation data. However, attenuation data alone does not account for variations in porosity distribution or type, and ignores the fact that other variables can influence attenuation besides porosity. This work was directed at determining additional parameters which can be used to define the defect structure in a composite.</p

Evolution of plastid genomes of Holcoglossum (Orchidaceae) with recent radiation

Abstract Background The plastid is a semiautonomous organelle with its own genome. Plastid genomes have been widely used as models for studying phylogeny, speciation and adaptive evolution. However, most studies focus on comparisons of plastid genome evolution at high taxonomic levels, and comparative studies of the process of plastome evolution at the infrageneric or intraspecific level remain elusive. Holcoglossum is a small genus of Orchidaceae, consisting of approximately 20 species of recent radiation. This made it an ideal group to explore the plastome mutation mode at the infrageneric or intraspecific level. Results In this paper, we reported 15 complete plastid genomes from 12 species of Holcoglossum and 1 species of Vanda. The plastid genomes of Holcoglossum have a total length range between 145 kb and 148 kb, encoding a set of 102 genes. The whole set of ndh-gene families in Holcoglossum have been truncated or pseudogenized. Hairpin inversion in the coding region of the plastid gene ycf2 has been found. Conclusions Using a comprehensive comparative plastome analysis, we found that all the indels between different individuals of the same species resulted from the copy number variation of the short repeat sequence, which may be caused by replication slippage. Annotation of tandem repeats shows that the variation introduced by tandem repeats is widespread in plastid genomes. The hairpin inversion found in the plastid gene ycf2 occurred randomly in the Orchidaceae

Safety of thoracic pedicle screw application using the funnel technique in Asians: a cadaveric evaluation

The objective of this cadaveric study is to determine the safety and outcome of thoracic pedicle screw placement in Asians using the funnel technique. Pedicle screws have superior biomechanical as well as clinical data when compared to other methods of instrumentation. However, misplacement in the thoracic spine can result in major neurological implications. There is great variability of the thoracic pedicle morphometry between the Western and the Asian population. The feasibility of thoracic pedicle screw insertion in Asians has not been fully elucidated yet. A pre-insertion radiograph was performed and surgeons were blinded to the morphometry of the thoracic pedicles. 240 pedicle screws were inserted in ten Asian cadavers from T1 to T12 using the funnel technique. 5.0 mm screws were used from T1 to T6 while 6.0 mm screws were used from T7 to T12. Perforations were detected by direct visualization via a wide laminectomy. The narrowest pedicles are found between T3 and T6. T5 pedicle width is smallest measuring 4.1 ± 1.3 mm. There were 24 (10.0%) Grade 1 perforations and only 1 (0.4%) Grade 2 perforation. Grade 2 or worse perforation is considered significant perforation which would threaten the neural structures. There were twice as many lateral and inferior perforations compared to medial perforations. 48.0% of the perforations occurred at T1, T2 and T3 pedicles. Pedicle fracture occurred in 10.4% of pedicles. Intra-operatively, the absence of funnel was found in 24.5% of pedicles. In conclusion, thoracic pedicle screws using 5.0 mm at T1–T6 and 6.0 mm at T7–T12 can be inserted safely in Asian cadavers using the funnel technique despite having smaller thoracic pedicle morphometry

Trap Door : Trans Cultural Production and the Politics of Visibility

"Essays, conversations, and archival investigations explore the paradoxes, limitations, and social ramifications of trans representation within contemporary culture. The increasing representation of trans identity throughout art and popular culture in recent years has been nothing if not paradoxical. Trans visibility is touted as a sign of a liberal society, but it has coincided with a political moment marked both by heightened violence against trans people (especially trans women of color) and by the suppression of trans rights under civil law. Trap Door grapples with these contradictions. The essays, conversations, and dossiers gathered here delve into themes as wide-ranging yet interconnected as beauty, performativity, activism, and police brutality. Collectively, they attest to how trans people are frequently offered “doors”—entrances to visibility and recognition—that are actually “traps,” accommodating trans bodies and communities only insofar as they cooperate with dominant norms. The volume speculates about a third term, perhaps uniquely suited for our time: the trapdoor, neither entrance nor exit, but a secret passageway leading elsewhere. Trap Door begins a conversation that extends through and beyond trans culture, showing how these issues have relevance for anyone invested in the ethics of visual culture." -- Publisher's websit

The major genetic determinants of HIV-1 control affect HLA class I peptide presentation.

Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified &gt;300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA-viral peptide interaction as the major factor modulating durable control of HIV infection