Bony canal and grooves of the middle meningeal artery: mythic structures in anatomy and neurosurgery?

Background: It has been previously published that the frontal branch of the middle meningeal artery (MMA) is usually embedded in a bony canal (BC). Although the incidence of the BC was over 70%, this structure is currently omitted both in anatomical nomenclature and in most of the literature. We found the same gap pertaining to the grooves for the MMA on the skull base. The aims of our study were to assess the incidence and morphometry of the MMA BC and grooves on the skull base. Materials and methods: Computed tomography (CT) scans of 378 patients, 172 skull bases as well as 120 sphenoidal bones and 168 temporal bones, and 12 histological specimens from 3 men and 3 women and 3 different regions of the MMA course were assessed. Results: Based on CT scans, the incidence of the BC was 85.44% and was significantly higher in females than in males. Most of the canals and grooves were bilateral. The mean canal length was 17.67 mm, the mean transverse diameter 1.33 mm, and the mean distance from the superior orbital fissure (dFOS) was 26.7 mm. In the skull bases, the BC incidence was 70.07%, the mean canal length 10.74 mm, and the mean dFOS was 19.16 mm. The groove for the MMA on the temporal and sphenoidal bones was present in 99.42% and 95.35%, respectively. Histological specimens confirmed the presence of the MMA and accompanying vein/s. Conclusions: Based on our results, we suggest the addition of the BC and grooves for the middle meningeal vessels to the upcoming version of the Terminologia Anatomica

Adolescent Self-Consent for Biomedical HIV Prevention Research: Implications for Institutional Review Board Approval and Implementation

Purpose The Adolescent Medicine Trials Network Protocol 113 (ATN113) is an open-label, multisite demonstration project and Phase II safety study of human immunodeficiency virus (HIV) preexposure prophylaxis with 15- to 17-year-old young men who have sex with men that requires adolescent consent for participation. The purpose of this study was to examine factors related to the process by which Institutional Review Boards (IRBs) and researchers made decisions regarding whether to approve and implement ATN113 so as to inform future biomedical HIV prevention research with high-risk adolescent populations. Methods Participants included 17 researchers at 13 sites in 12 states considering ATN113 implementation. Qualitative descriptive methods were used. Data sources included interviews and documents generated during the initiation process. Results A common process for initiating ATN113 emerged, and informants described how they identified and addressed practical, ethical, and legal challenges that arose. Informants described the process as responding to the protocol, preparing for IRB submission, abstaining from or proceeding with submission, responding to IRB concerns, and reacting to the outcomes. A complex array of factors impacting approval and implementation were identified, and ATN113 was ultimately implemented in seven of 13 sites. Informants also reflected on lessons learned that may help inform future biomedical HIV prevention research with high-risk adolescent populations. Conclusions The results illustrate factors for consideration in determining whether to implement such trials, demonstrate that such protocols have the potential to be approved, and highlight a need for clearer standards regarding biomedical HIV prevention research with high-risk adolescent populations

Minors' and Young Adults' Experiences of the Research Consent Process in a Phase II Safety Study of Pre-exposure Prophylaxis for HIV

PURPOSE: There is a persistent HIV epidemic among sexual and gender minority adolescents in the U.S. Oral pre-exposure prophylaxis (PrEP) is an efficacious prevention strategy, but not yet approved for minors. Minors' access to biomedical HIV prevention technologies is impeded by the ethical and legal complexities of consent to research participation. We explore autonomous consent and study experiences among minor and adult participants in Project PrEPare, a Phase II safety study of PrEP for HIV prevention. METHODS: Data for this mixed-methods descriptive study were collected via self-administered web-survey and in-depth telephone interviews in early 2016. Eligible participants were previously enrolled in Project PrEPare. We attempted to contact 191 participants; 74 were reached and expressed interest in participating and 58 enrolled. RESULTS: Participants nearly universally felt well informed, understood the study, and freely volunteered with the clear understanding they could withdraw any time. All felt supported by study staff, but a small minority wished for more support during enrollment. Minors were more likely than adults to indicate a wish for more support in decision-making, and adults expressed higher satisfaction with their decision compared to minors. There was no association between elements of consent and Project PrEPare study outcomes. CONCLUSIONS: Participants had an overwhelmingly positive experience in a Phase II safety study of PrEP for HIV prevention. Some minors wished for more support during the decision-making process, but none consulted their parents about the decision. Our results support the inclusion of decisional supports in consent processes for adolescents, while also protecting their privacy

Search for weakly interacting sub-eV particles with the OSQAR laser-based experiment: results and perspectives

Recent theoretical and experimental studies highlight the possibility of new fundamental particle physics beyond the Standard Model that can be probed by sub-eV energy experiments. The OSQAR photon regeneration experiment looks for "Light Shining through a Wall" (LSW) from the quantum oscillation of optical photons into "Weakly Interacting Sub-eV Particles" (WISPs), like axion or axion-like particles (ALPs), in a 9 T transverse magnetic field over the unprecedented length of $2 \times 14.3$ m. No excess of events has been detected over the background. The di-photon couplings of possible new light scalar and pseudo-scalar particles can be constrained in the massless limit to be less than $8.0\times10^{-8}$ GeV$^{-1}$. These results are very close to the most stringent laboratory constraints obtained for the coupling of ALPs to two photons. Plans for further improving the sensitivity of the OSQAR experiment are presented.Comment: 7 pages, 7 figure

Dense quark matter in compact stars

The densest predicted state of matter is colour-superconducting quark matter, in which quarks near the Fermi surface form a condensate of Cooper pairs. This form of matter may well exist in the core of compact stars, and the search for signatures of its presence is an ongoing enterprise. Using a bag model of quark matter, I discuss the effects of colour superconductivity on the mass-radius relationship of compact stars, showing that colour superconducting quark matter can occur in compact stars at values of the bag constant where ordinary quark matter would not be allowed. The resultant ``hybrid'' stars with colour superconducting quark matter interior and nuclear matter surface have masses in the range 1.3-1.6 Msolar and radii 8-11 km. Once perturbative corrections are included, quark matter can show a mass-radius relationship very similar to that of nuclear matter, and the mass of a hybrid star can reach 1.8 \Msolar.Comment: 11 pages, for proceedings of SQM 2003 conference; references added, abstract reworde

Stellar Populations in the Central 0.5 pc of Our Galaxy III: The Dynamical Sub-structures

We measure the 3D kinematic structures of the young stars within the central 0.5 parsec of our Galactic Center using the 10 m telescopes of the W.~M.~Keck Observatory over a time span of 25 years. Using high-precision measurements of positions on the sky, and proper motions and radial velocities from new observations and the literature, we constrain the orbital parameters for each young star. Our results show two statistically significant sub-structures: a clockwise stellar disk with 18 candidate stars, as has been proposed before, but with an improved disk membership; a second, almost edge-on plane of 10 candidate stars oriented East-West on the sky that includes at least one IRS 13 star. We estimate the eccentricity distribution of each sub-structure and find that the clockwise disk has = 0.39 and the edge-on plane has = 0.68. We also perform simulations of each disk/plane with incompleteness and spatially-variable extinction to search for asymmetry. Our results show that the clockwise stellar disk is consistent with a uniform azimuthal distribution within the disk. The edge-on plane has an asymmetry that cannot be explained by variable extinction or incompleteness in the field. The orientation, asymmetric stellar distribution, and high eccentricity of the edge-on plane members suggest that this structure may be a stream associated with the IRS 13 group. The complex dynamical structure of the young nuclear cluster indicates that the star formation process involved complex gas structures and dynamics and is inconsistent with a single massive gaseous disk.Comment: 41 pages, 26 figures, 13 tables, 2 appendices. Accepted for publication in Ap

Intimate partner violence and oral HIV pre-exposure prophylaxis adherence among young African women

Objective: To estimate the effect of intimate partner violence (IPV) on oral pre-exposure prophylaxis (PrEP) adherence among adolescent girls and young women (AGYW). Design: We conducted a secondary analysis of data from HIV Prevention Trials Network 082 (HPTN 082), a multisite prospective study designed to assess oral PrEP adherence among AGYW in southern Africa. Methods: We estimated the relative prevalence of high PrEP adherence 3 and 6 months after initiation among AGYW 16 – 25 years who reported a history of any IPV in the past year at enrollment versus AGYW who did not, both overall and by age. High adherence was defined as an intracellular tenofovir-diphosphate concentration at least 700 fmol/ punch or more dried blood spots. Results: Among 409 PrEP-initiating AGYW, half (49%) reported experiencing any IPV by a current/recent partner in the year prior to enrollment. Overall, a similar proportion of AGYW who reported IPV had high PrEP adherence at months 3 and 6 as AGYW who did not report IPV. There was, however, evidence of effect modification by age at month 3: among AGYW less than 21 years old, those who reported IPV were less than half as likely to have high adherence [adjusted PR (aPR) = 0.43, 95% confidence interval (CI) 0.22– 0.86]; among AGYW aged 21 years or older, those who reported IPV were more than twice as likely to have high adherence (aPR = 2.21, 95% CI 1.34– 3.66). At month 6, effect estimates within each age stratum were consistent in direction to those at month 3. Conclusion: IPV events may either impede or motivate PrEP adherence among African AGYW, with age appearing to be an important consideration for IPV-related adherence interventions

Latest Results of the OSQAR Photon Regeneration Experiment for Axion-Like Particle Search

The OSQAR photon regeneration experiment searches for pseudoscalar and scalar axion-like particles by the method of "Light Shining Through a Wall", based on the assumption that these weakly interacting sub-eV particles couple to two photons to give rise to quantum oscillations with optical photons in strong magnetic field. No excess of events has been observed, which constrains the di-photon coupling strength of both pseudoscalar and scalar particles down to $5.7 \cdot 10^{-8}$ GeV$^{-1}$ in the massless limit. This result is the most stringent constraint on the di-photon coupling strength ever achieved in laboratory experiments.Comment: 6 pages, 5 figures. appears in Proceedings of the 10th PATRAS Workshop on Axions, WIMPs and WISPs (2014

Determination of ππ\pi\pi scattering lengths from measurement of π+π−\pi^+\pi^- atom lifetime

The DIRAC experiment at CERN has achieved a sizeable production of $\pi^+\pi^-$ atoms and has significantly improved the precision on its lifetime determination. From a sample of 21227 atomic pairs, a 4% measurement of the S-wave $\pi\pi$ scattering length difference $|a_0-a_2| = (.0.2533^{+0.0080}_{-0.0078}|_\mathrm{stat}.{}^{+0.0078}_{-0.0073}|_\mathrm{syst})M_{\pi^+}^{-1}$ has been attained, providing an important test of Chiral Perturbation Theory.Comment: 6 pages, 6 figure