Automatic, fast and robust characterization of noise distributions for diffusion MRI

Knowledge of the noise distribution in magnitude diffusion MRI images is the centerpiece to quantify uncertainties arising from the acquisition process. The use of parallel imaging methods, the number of receiver coils and imaging filters applied by the scanner, amongst other factors, dictate the resulting signal distribution. Accurate estimation beyond textbook Rician or noncentral chi distributions often requires information about the acquisition process (e.g. coils sensitivity maps or reconstruction coefficients), which is not usually available. We introduce a new method where a change of variable naturally gives rise to a particular form of the gamma distribution for background signals. The first moments and maximum likelihood estimators of this gamma distribution explicitly depend on the number of coils, making it possible to estimate all unknown parameters using only the magnitude data. A rejection step is used to make the method automatic and robust to artifacts. Experiments on synthetic datasets show that the proposed method can reliably estimate both the degrees of freedom and the standard deviation. The worst case errors range from below 2% (spatially uniform noise) to approximately 10% (spatially variable noise). Repeated acquisitions of in vivo datasets show that the estimated parameters are stable and have lower variances than compared methods.Comment: v2: added publisher DOI statement, fixed text typo in appendix A

Are autistic traits measured equivalently in individuals with and without an Autism Spectrum Disorder?:An invariance analysis of the Autism Spectrum Quotient Short Form

It is common to administer measures of autistic traits to those without autism spectrum disorders (ASDs) with, for example, the aim of understanding autistic personality characteristics in non-autistic individuals. Little research has examined the extent to which measures of autistic traits actually measure the same traits in the same way across those with and without an ASD. We addressed this question using a multi-group confirmatory factor invariance analysis of the Autism Quotient Short Form (AQ-S: Hoekstra et al. in J Autism Dev Disord 41(5):589-596, 2011) across those with (n = 148) and without (n = 168) ASD. Metric variance (equality of factor loadings), but not scalar invariance (equality of thresholds), held suggesting that the AQ-S measures the same latent traits in both groups, but with a bias in the manner in which trait levels are estimated. We, therefore, argue that the AQ-S can be used to investigate possible causes and consequences of autistic traits in both groups separately, but caution is due when combining or comparing levels of autistic traits across the two group

Immunotherapy of lung cancer: An update

In Germany lung cancer is the leading cause of cancer-associated death in men. Surgery, chemotherapy and radiation may enhance survival of patients suffering from lung cancer but the enhancement is typically transient and mostly absent with advanced disease; eventually more than 90% of lung cancer patients will die of disease. New approaches to the treatment of lung cancer are urgently needed. Immunotherapy may represent one new approach with low toxicity and high specificity but implementation has been a challenge because of the poor antigenic characterization of these tumors and their ability to escape immune responses. Several different immunotherapeutic treatment strategies have been developed. This review examines the current state of development and recent advances with respect to non-specific immune stimulation, cellular immunotherapy ( specific and non-specific), therapeutic cancer vaccines and gene therapy for lung cancer. The focus is primarily placed on immunotherapeutic cancer treatments that are already in clinical trial or well progressed in preclinical studies. Although there seems to be a promising future for immunotherapy in lung cancer, presently there is not standard immunotherapy available for clinical routine

The QUIJOTE experiment: project overview and first results

QUIJOTE (Q-U-I JOint TEnerife) is a new polarimeter aimed to characterize the polarization of the Cosmic Microwave Background and other Galactic and extragalactic signals at medium and large angular scales in the frequency range 10-40 GHz. The multi-frequency (10-20~GHz) instrument, mounted on the first QUIJOTE telescope, saw first light on November 2012 from the Teide Observatory (2400~m a.s.l). During 2014 the second telescope has been installed at this observatory. A second instrument at 30~GHz will be ready for commissioning at this telescope during summer 2015, and a third additional instrument at 40~GHz is now being developed. These instruments will have nominal sensitivities to detect the B-mode polarization due to the primordial gravitational-wave component if the tensor-to-scalar ratio is larger than r=0.05.Comment: To appear in "Highlights of Spanish Astrophysics VIII", Proceedings of the XI Scientific Meeting of the Spanish Astronomical Society, Teruel, Spain (2014

Brief report:An evaluation of the AQ-10 as a brief screening instrument for ASD in adults

There is a need for brief screening instruments for autistic spectrum disorders (ASD) that can be used by frontline healthcare professionals to aid in the decision as to whether an individual should be referred for a full diagnostic assessment. In this study we evaluated the ability of a short form of the autism spectrum quotient (AQ) questionnaire, the 10 item AQ-10, to correctly classify individuals as having or not having ASD. In a sample of 149 individuals with ASD and 134 controls without an ASD diagnosis, we found that the full AQ (AQ-50) abridged AQ (AQ-S) and AQ-10 all performed well as a screen for ASD. ROC analysis indicated that sensitivity, specificity and area under the curve were very similar at suggested cut-off's for ASD across measures, with little difference in performance between the AQ-10 and full AQ-50. Results indicate the potential usefulness of the AQ-10 as a brief screen for ASD

Planck pre-launch status: calibration of the Low Frequency Instrument flight model radiometers

The Low Frequency Instrument (LFI) on-board the ESA Planck satellite carries eleven radiometer subsystems, called Radiometer Chain Assemblies (RCAs), each composed of a pair of pseudo-correlation receivers. We describe the on-ground calibration campaign performed to qualify the flight model RCAs and to measure their pre-launch performances. Each RCA was calibrated in a dedicated flight-like cryogenic environment with the radiometer front-end cooled to 20K and the back-end at 300K, and with an external input load cooled to 4K. A matched load simulating a blackbody at different temperatures was placed in front of the sky horn to derive basic radiometer properties such as noise temperature, gain, and noise performance, e.g. 1/f noise. The spectral response of each detector was measured as was their susceptibility to thermal variation. All eleven LFI RCAs were calibrated. Instrumental parameters measured in these tests, such as noise temperature, bandwidth, radiometer isolation, and linearity, provide essential inputs to the Planck-LFI data analysis.Comment: 15 pages, 18 figures. Accepted for publication in Astronomy and Astrophysic

Understory 2014

“Art is the struggle to be, in a particular sort of way, virtuous.” —Iris Murdoch Indeed, when we embark on any creative adventure it is with the purpose of conveying a certain truth; an emotion, an idea that brings us together and reminds us of the innate consciousness that dwells within. Understory is emblematic of this; where individuals intent on honing their craft can join others to become a part of something greater, their work immortalized to become a time capsule. Decades from now a volume of Understory may be discovered on a dusty bookshelf in some forgotten corner and the lucky explorer who finds it shall be enlightened by pages of gold. We, as editors of Understory 2014, have worked very hard this year to put together a journal that showcases the very best of the University of Alaska Anchorage undergraduate student work. We hope you enjoy your journey through this issue as much as we have enjoyed ours. Thank you to the English and Art Departments, for the staff and faculty’s unerring support of our club; to Provost Baker, for seeing and believing in the vision of Understory; and to our club’s faculty advisor, Douglass Bourne, for his guidance and tireless assistance. Finally, thank you to the wonderful students who submit such excellent work each year. Without your passion for the arts, we would not be here.Staff / Letter from the Editors / Glass Blower / Writing / Obsolete Evolution / Permafrost / Phoenix / Untitled / Ratio / Tripping / Abiogenesis / My Heart Beats for You / Meeting of the Fingerprint Lines / You Are No Stranger / Nightmare Fuel / Cane-Sugar / Gossamer Strands / Panthera Gold / Butterfly / A Mantis Too Far / Long and Winding Road / Chasing Shadows / Merisunas / Chequer Grove / Modzilla / Beans / Little Red and Mr. Wolf / In Memoriam, Joel Fletcher Armstrong / Glance / Courage / Uranium Waltz / Danger / Journey to the West / Antumbra / Roaring Like a Lion / Pre-boarding / Untitled / How Do You Say a Word / Fishing for Doom/ Contributor

Use Of Informatıon And Communıcatıon Technology (Ict) Devıces For Instructıonal Delıvery In Secondary Schools In Ebonyı State Of Nıgerıa

The study examined teachers perceptions on the use of information and communication technology (ICT) devices for instructional delivery in secondary schools in Ebonyi State, Nigeria. Four research questions guided the study. The population of the study comprised of all the three thousand two hundred and eighty-five (3,285) teacher in the two hundred and twenty-one (221) public secondary schools in Ebonyi State. Simple random sampling technique was used to select (8) teachers each from ninety schools used for the study to give a sample of seven hundred and twenty (720) respondents. The instrument used for data collection was structured questionnaire. Pearson’s Moment Correlation Co-efficient was used to calculate the reliability co-efficient of the pilot tests to get established reliability value of 0.79. The data collected were analysed using mean scores. It was found among other things that ICT devices are not adequately available, most available ICT devices are not in good working condition in schools studied, hence they are not adequately used and above all trained personnel are not also adequately available to operate the functional ones. Government through her appropriate agencies should as a matter of urgency procure and distribute the necessary ICT devices to secondary schools, more trained personnel should be recruited but for the interim the available ones could be retrained through short term holiday programmes, workshops and conferences to ensure adequate use and maintenance of these ICT devices as this will go a long way in improving instructional delivery in Ebonyi State Secondary Schools

Genetic and environmental transactions underlying the associationbetween physical fitness/physical exercise and body composition

We examined mean effects and variance moderating effects of measures of physical activity and fitness on six measures of adiposity and their reciprocal effects in a subsample of the population-representative Danish Twin Registry. Consistent with prior studies, higher levels of physical activity suppressed variance in adiposity, but this study provided further insight. Variance suppression appeared to have both genetic and environmental pathways. Some mean effects appeared due to reciprocal influences of environmental circumstances differing among families but not between co-twins, suggesting these reciprocal effects are uniform. Some variance moderating effects also appeared due to biases in individual measures of adiposity, as well as to differences and inaccuracies in measures of physical activity. This suggests a need to avoid reliance on single measures of both physical activity and adiposity in attempting to understand the pathways involved in their linkages, and constraint in interpreting results if only single measures are available. Future research indications include identifying which physical activity-related environmental circumstances have relatively uniform effects on adiposity in everyone, and which should be individually tailored to maximize motivation to continue involvement.</p