Understanding Rates of Marijuana Use and Consequences Among Adolescents in a Changing Legal Landscape.

Purpose of Review:There is not one answer to address whether marijuana use has increased, decreased, or stayed the same given changes in state legalization of medical and non-medical marijuana in the USA. Recent Findings:Evidence suggests some health benefits for medical marijuana; however, initiation of marijuana use is a risk factor for developing problem cannabis use. Though use rates have remained stable over recent years, about one in three 10th graders report marijuana use, most adolescents do not view the drug as harmful, and over 650,000 youth aged 12 to 17 struggle with cannabis use disorder. Summary:Although the health benefits of medical marijuana are becoming better understood, more research is needed. Intervention and prevention programs must better address effects of marijuana, acknowledging that while there may be some benefits medically, marijuana use can affect functioning during adolescence when the brain is still developing

The 8 o'clock Arc: A Serendipitous Discovery of a Strongly Lensed Lyman Break Galaxy in the SDSS DR4 Imaging Data

We report on the serendipitous discovery of the brightest Lyman Break Galaxy (LBG) currently known, a galaxy at z=2.73 that is being strongly lensed by the z=0.38 Luminous Red Galaxy (LRG) SDSS J002240.91+143110.4. The arc of this gravitational lens system, which we have dubbed the "8 o'clock arc" due to its time of discovery, was initially identified in the imaging data of the Sloan Digital Sky Survey Data Release 4 (SDSS DR4); followup observations on the Astrophysical Research Consortium (ARC) 3.5m telescope at Apache Point Observatory confirmed the lensing nature of this system and led to the identification of the arc's spectrum as that of an LBG. The arc has a spectrum and a redshift remarkably similar to those of the previous record-holder for brightest LBG (MS 1512-cB58, a.k.a "cB58"), but, with an estimated total magnitude of (g,r,i) = (20.0,19.2,19.0) and surface brightness of (mu_g,mu_r,mu_i) = (23.3, 22.5, 22.3) mag/arcsec^2, the 8 o'clock arc is thrice as bright. The 8 o'clock arc, which consists of three lensed images of the LBG, is 162deg (9.6arcsec) long and has a length-to-width ratio of 6:1. A fourth image of the LBG -- a counter-image -- can also be identified in the ARC 3.5m g-band images. A simple lens model for the system assuming a singular isothermal ellipsoid potential yields an Einstein radius of 2.91+/-0.14 arcsec, a total mass for the lensing LRG (within the (10.6+/-0.5)/h kpc enclosed by the lensed images) of 1.04x10^12/h Msun, and a magnification factor for the LBG of 12.3(+15/-3.6). The LBG itself is intrinsically quite luminous (approximately 6L*) and shows indications of massive recent star formation, perhaps as high as 160/h Msun/year.Comment: 4 pages 5 figures, submitted to ApJ Letter

“K Cramps,” Recurrent Abdominal Pain in a Patient with Chronic Ketamine Use: A Case Report

Introduction: Medical and nonmedical ketamine use is increasing in the United States. This will likely lead to an increase in emergency department (ED) visits in individuals experiencing associated side effects. Physicians will need to be able to effectively recognize and manage ketamine-related complications. Case Report: A 31-year-old male with a three-year history of inhalational, intramuscular, and intravenous nonmedical ketamine use presented to the ED twice within a week with symptoms of severe atraumatic back pain, abdominal pain, and dyspepsia. A comprehensive workup, including advanced imaging, was unrevealing for identifiable causes, and the patient was discharged with instructions for primary care follow-up for further evaluation. The patient used information shared on Reddit, an online forum and social network, to identify that the cause of his pain was related to chronic ketamine use. Subsequently, upon discontinuation of ketamine, the pain improved in 24 hours. The patient self-navigated to addiction treatment. Conclusion: Emergency physicians should consider sequelae of chronic ketamine use as a possible cause for gastrointestinal and urologic symptoms in the ED. In addition to thorough examination and assessment for other acute medical problems, patients should be offered education, symptomatic treatment, and linkage to harm reduction and substance use disorder treatment services

Atypical Teratoid Rhabdoid Tumor: two Case Reports and an Analysis of Adult Cases With Implications for Pathophysiology and Treatment

We present the first quantitative analysis of atypical teratoid rhabdoid tumors (ATRT) in adults, including two patients from our own institutions. These are of interest as one occurred during pregnancy and one is a long-term survivor. Our review of pathological findings of 50 reported cases of adult ATRT leads us to propose a solely ectodermal origin for the tumor and that epithelial-mesenchymal transition (EMT) is a defining feature. Thus, the term ATRT may be misleading. Our review of clinical findings shows that ATRT tends to originate in mid-line structures adjacent to the CSF, leading to a high rate of leptomeningeal dissemination. Thus, we hypothesize that residual undifferentiated ectoderm in the circumventricular organs, particularly the pituitary and pineal glands, is the most common origin for these tumors. We note that if growth is not arrested soon after diagnosis, or after the first relapse/progression, death is almost universal. While typically rapidly fatal (as in our first case), long-term remission is possible (as in our second). Significant predictors of prognosis were the extent of resection and the use of chemotherapy. Glial differentiation (GFAP staining) was strongly associated with leptomeningeal metastases (chi-squared p = 0.02) and both predicted markedly worse outcomes. Clinical trials including adults are rare. ATRT is primarily a disease of infancy and radiotherapy is generally avoided in those aged less than 3 years old. Treatment options in adults differ from infants in that cranio-spinal irradiation is a viable adjunct to systemic chemotherapy in the adult population. Given the grave prognosis, this combined approach appears reasonable. As effective chemotherapy is likely to cause myelosuppression, we recommend that stem-cell rescue be available locally

The Sloan Bright Arcs Survey: Four Strongly Lensed Galaxies with Redshift >2

We report the discovery of four very bright, strongly-lensed galaxies found via systematic searches for arcs in Sloan Digital Sky Survey Data Release 5 and 6. These were followed-up with spectroscopy and imaging data from the Astrophysical Research Consortium 3.5m telescope at Apache Point Observatory and found to have redshift $z>2.0$. With isophotal magnitudes $r = 19.2 - 20.4$ and 3\arcsec-diameter magnitudes $r = 20.0 - 20.6$, these systems are some of the brightest and highest surface brightness lensed galaxies known in this redshift range. In addition to the magnitudes and redshifts, we present estimates of the Einstein radii, which range from 5.0 \arcsec to 12.7 \arcsec, and use those to derive the enclosed masses of the lensing galaxies

Synthesis and characterisation of pyrene-labelled polydimethylsiloxane networks: towards the in situ detection of strain in silicone elastomers

Pyrene-substituted polyhydromethylsiloxanes (PHMS-Py-x) were synthesised by the hydrosilylation reaction of prop-3-enyloxymethylpyrene with polyhydromethylsiloxane (M-n = 3700). The ratio of pyrene substituent to Si-H unit was varied to afford a range of pyrene-functionalised polysiloxanes. These copolymers were subsequently incorporated into polydimethylsiloxane (PDMS) elastomers by curing via either Pt(0) catalysed hydrosilylation with divinyl-terminated PDMS (M-n = 186) and tetrakis(dimethylsiloxy) silane, or Sn(II) catalysed condensation with alpha,omega-dihydroxyPDMS (M-n = 26 000) and tetraethoxysilane. An alternative method involving the synthesis and integration of [3-(pyren-1-ylmethoxy)propyl]triethoxysilane (Py-TEOS) into PDMS elastomers was also investigated: a mixture of alpha,omega-dihydroxyPDMS (M-n = 26 000), tetraethoxysilane, and Py-TEOS was cured using an Sn( II) catalyst. Certain of the resulting fluorescent pyrene-labelled elastomers were studied by differential scanning calorimetry and dynamic mechanical analysis. No significant changes were observed in the thermal or mechanical properties of the elastomers containing pyrene when compared to otherwise identical samples not containing pyrene. All of the pyrene-containing elastomers were demonstrated to be fluorescent under suitable excitation in a photoluminescent spectrometer. Two of the elastomers were placed in a photoluminescence spectrometer and subjected to cycles of extension and relaxation (strain = 0-16.7%) while changes in the emission spectra were monitored. The resulting spectra of the elastomer containing the PHMS-Py-50 copolymers were variable and inconsistent. However, the emission peaks of elastomers containing Py-TEOS displayed clear and reproducible changes in fluorescence intensity upon stretching and relaxation. The intensity of the monomer and excimer emission peaks was observed to increase with elongation of the sample and decrease upon relaxation. Furthermore, the ratio of the intensities of the excimer : monomer peak decreased with elongation and increased with relaxation. In neither case was there appreciable hysteresis, suggesting that fluorescent labelling of elastomers is a valid approach for the non-invasive in situ monitoring of stress and strain in such materials

Historical Analysis of Bibliometric Trends in the Journal of Pediatric Orthopaedics With a Particular Focus on Sex

Background: Orthopaedics is the clinical discipline with the lowest percentage of female residents and faculty. Pediatric orthopaedics has a higher percentage of women than other orthopaedic subspecialties. It was the purpose of this study to examine bibliometric trends in the Journal of Pediatric Orthopaedics (JPO) with a specific focus on sex. Methods: A bibliometeric analysis for the years 2015, 2005, 1995, 1985, 1981 was performed. The names of first and corresponding authors; corresponding author position; country of origin; number of institutions, countries, authors, printed pages, and references was tabulated. Author sex was identified for the first and corresponding authors using the “Baby Name Guesser” (www.gpeters.com/names/baby-names.php). A P<0.05 was considered significant. Results: There were 746 publications; 68.7% were from North America. The average number of authors, corresponding author position, collaborating institutions, countries, and number of references increased, whereas the number of printed pages decreased. Asia had the greatest number of authors (4.4), with Australia/New Zealand the fewest (3.4). Sex was determined for 98.3% of the first authors and 98.5% of the corresponding authors. There was a significant increase in the number of female first authors over time (5.9% to 25.6%, P<10−6), especially in Europe and North America. There were significant increase in the number of female corresponding authors over time (5.8% to 17.6%, P=0.000009). There was a significant trend to have a greater percentage of both female first and corresponding authors over time (P=0.0005) with a reverse trend for both male first and corresponding authors (P<10−6). Conclusions: In this study, we noted that the number of female first and corresponding authors in Journal of Pediatric Orthopaedics has been steadily increasing. This should result in more female pediatric orthopaedic surgeons in academic faculty positions

Rest-Frame Optical Spectra of Three Strongly Lensed Galaxies at z~2

We present Keck II NIRSPEC rest-frame optical spectra for three recently discovered lensed galaxies: the Cosmic Horseshoe (z = 2.38), the Clone (z = 2.00), and SDSS J090122.37+181432.3 (z = 2.26). The boost in signal-to-noise ratio (S/N) from gravitational lensing provides an unusually detailed view of the physical conditions in these objects. A full complement of high S/N rest-frame optical emission lines is measured, spanning from rest-frame 3600 to 6800AA, including robust detections of fainter lines such as H-gamma, [SII]6717,6732, and in one instance [NeII]3869. SDSS J090122.37+181432.3 shows evidence for AGN activity, and therefore we focus our analysis on star-forming regions in the Cosmic Horseshoe and the Clone. For these two objects, we estimate a wide range of physical properties, including star-formation rate (SFR), metallicity, dynamical mass, and dust extinction. In all respects, the lensed objects appear fairly typical of UV-selected star-forming galaxies at z~2. The Clone occupies a position on the emission-line diagnostic diagram of [OIII]/H-beta vs. [NII]/H-alpha that is offset from the locations of z~0 galaxies. Our new NIRSPEC measurements may provide quantitative insights into why high-redshift objects display such properties. From the [SII] line ratio, high electron densities (~1000 cm^(-3)) are inferred compared to local galaxies, and [OIII]/[OII] line ratios indicate higher ionization parameters compared to the local population. Building on previous similar results at z~2, these measurements provide further evidence (at high S/N) that star-forming regions are significantly different in high-redshift galaxies, compared to their local counterparts (abridged).Comment: 16 pages, 8 figures. Accepted for publication in the Astrophysical Journa

Discovery of A Very Bright, Strongly-Lensed z=2 Galaxy in the SDSS DR5

We report on the discovery of a very bright z = 2.00 star-forming galaxy that is strongly lensed by a foreground z=0.422 luminous red galaxy (LRG). This system was found in a systematic search for bright arcs lensed by LRGs and brightest cluster galaxies in the Sloan Digital Sky Survey Data Release 5 sample. Follow-up observations on the Subaru 8.2m telescope on Mauna Kea and the Astrophysical Research Consortium 3.5m telescope at Apache Point Observatory confirmed the lensing nature of this system. A simple lens model for the system, assuming a singular isothermal ellipsoid mass distribution, yields an Einstein radius of 3.82 +/- 0.03 arcsec or 14.8 +/- 0.1 kpc/h at the lens redshift. The total projected mass enclosed within the Einstein radius is 2.10 +/- 0.03 x 10^12 M_sun/h, and the magnification factor for the source galaxy is 27 +/- 1. Combining the lens model with our gVriz photometry, we find an (unlensed) star formation rate for the source galaxy of 32 M_sun/h / yr, adopting a fiducial constant star formation rate model with an age of 100 Myr and E(B-V) = 0.25. With an apparent magnitude of r = 19.9, this system is among the very brightest lensed z >= 2 galaxies, and provides an excellent opportunity to pursue detailed studies of the physical properties of an individual high-redshift star-forming galaxy.Comment: 31 pages, 12 figures, 4 tables, submitted to Ap

Deficiency of the zinc finger protein ZFP106 causes motor and sensory neurodegeneration

Acknowledgements We are indebted to Jim Humphries, JennyCorrigan, LizDarley, Elizabeth Joynson, Natalie Walters, Sara Wells and the whole necropsy, histology, genotyping and MLC ward 6 teams at MRC Harwell for excellent technical assistance. We thank the staff of the WTSI Illumina Bespoke Team for the RNA-seq data, the Sanger Mouse Genetics Project for the initial mouse characterization and Dr David Adams for critical reading of the manuscript. We also thank KOMP for the mouse embryonic stem cells carrying the knockout first promoter-less allele (tm1a(KOMP)Wtsi) within Zfp016. Conflict of Interest statement. None declared. Funding This work was funded by the UK Medical Research Council (MRC) to A.A.-A. and a Motor Neurone Disease Association (MNDA) project grant to A.A.-A. and EMCF. D.L.H.B. is a Wellcome Trust Senior Clinical Scientist Fellow and P.F. is a MRC/MNDA Lady Edith Wolfson Clinician Scientist Fellow. Funding to pay the Open Access publication charges for this article was provided by the MRC grant number: MC_UP_A390_1106.Peer reviewedPublisher PD