A new method for the inversion of atmospheric parameters of A/Am stars

We present an automated procedure that derives simultaneously the effective temperature $T_{eff}$, the surface gravity logg, the metallicity [Fe/H], and the equatorial projected rotational velocity vsini for "normal" A and Am stars. The procedure is based on the principal component analysis inversion method of Paletou et al. (2015a). A sample of 322 high resolution spectra of F0-B9 stars, retrieved from the Polarbase, SOPHIE, and ELODIE databases, were used to test this technique with real data. We have selected the spectral region from 4400-5000\AA\ as it contains many metallic lines and the Balmer H$\beta$ line. Using 3 datasets at resolving powers of R=42000, 65000 and 76000, about 6.6x$10^6$ synthetic spectra were calculated to build a large learning database. The Online Power Iteration algorithm was applied to these learning datasets to estimate the principal components (PC). The projection of spectra onto the few PCs offered an efficient comparison metric in a low dimensional space. The spectra of the well known A0- and A1-type stars, Vega and Sirius A, were used as control spectra in the three databases. Spectra of other well known A-type stars were also employed in order to characterize the accuracy of the inversion technique. All observational spectra were inverted and atmospheric parameters derived. After removal of a few outliers, the PCA-inversion method appears to be very efficient in determining $T_{eff}$, [Fe/H], and vsini for A/Am stars. The derived parameters agree very well with previous determinations. Using a statistical approach, deviations of around 150 K, 0.35 dex, 0.15 dex, and 2 km/s were found for $T_{eff}$, logg, [Fe/H], and vsini with respect to literature values for A-type stars. The PCA-inversion proves to be a very fast, practical, and reliable tool for estimating stellar parameters of FGK and A stars, and deriving effective temperatures of M stars.Comment: 16 pages, 9 figures. Accepted in A&

The potential of Manitoba chokecherry as a source of high natural antioxidants

Consumption of fruits and vegetables is shown to be beneficial for protecting health and preventing some chronic diseases such as cancer, cardiovascular disease, and stroke. The positive health effects have been mainly due to the contributions of their natural antioxidant capacity. Chokecherry (Prunus virginiana), a unique fruit, is a member of the Rose family and native to North America. Here we demonstrate that chokecherry fruit with strong antioxidant capacity is available in Manitoba, and that its potent antioxidant potential can be developed for health benefits in value-added applications.These findings are useful for developing novel value-added antioxidant products from chokecherry because of its phytochemical profile associated with health protection and prevention of disease. The results provide evidence essential for breeding novel cultivars of fruit plants with strong natural antioxidants

FRB microstructure revealed by the real-time detection of FRB170827

We report a new fast radio burst (FRB) discovered in real-time as part of the UTMOST project at the Molonglo Observatory Synthesis Radio Telescope. FRB170827 was first detected with our low-latency (20 ± 7 Jy ms, and is narrow with a width of ∼400 s at 10 per cent of its maximum amplitude. However, the burst shows three temporal components, the narrowest of which is ∼30 s, and a scattering time-scale of 4.1 ± 2.7 s. The FRB shows spectral modulations on frequency scales of 1.5 MHz and 0.1 MHz. Both are prominent in the dynamic spectrum, which shows a very bright region of emission between 841 and 843 MHz, and weaker and patchy emission across the entire band. We show that the fine spectral structure could arise in the FRB host galaxy, or its immediate vicinity

Reflection Photoelastic Stress Analysis of a Dental Bridge

The stress distribution on the surface of a four unit gold bridge was determined by reflection photoelasticity. The highest stress concentration was at the soldered joints. The distribution of stress was a function of the support of the abutment teeth. Good support caused the bridge to function as one that was fixed at both ends, whereas poor support caused it to function as a cantilever beam.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68063/2/10.1177_00220345710500052701.pd

Apparent Modulus of Elasticity of Dental Amalgams

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66932/2/10.1177_00220345750540043301.pd

Hubungan Budaya Organisasi Dengan Kinerja Petugas Perpustakaan Di Kantor Perpustakaan Dan Arsip Daerah Kabupaten Purbalingga

Tujuan dari penelitian ini adalah untuk mengetahui bagaimana hubungan budaya organisasi dengan kinerja petugas perpustakaan di Kantor Perpustakaan dan Arsip Daerah Kabupaten Purbalingga. Subjek dalam penelitian ini adalah budaya organisasi yang menekankan pada model level budaya organisasi yang meliputi artefak, nilai-nilai dan asumsi dasar. Sedangkan objeknya adalah kinerja petugas perpustakaan dengan indikator kualitas dan kuantitas yang diberikan, waktu kerja dan kerjasama antar sesama petugas. Jenis penelitian yang digunakan adalah penelitian kualitatif dengan metode deskriptif. Penentuan informan dilakukan dengan teknik purposive sampling dengan jumlah informan sebanyak 6 orang. Sementara itu, teknik pengumpulan datanya menggunakan wawancara mendalam, observasi partisipatif dan dokumentasi. Hasil penelitian menunujukan bahwa budaya organisasi yang ada di Kantor Perpustakaan dan Arsip Daerah Kabupaten Purbalingga masih terbilang lemah, hal tersebut berdampak pada kinerja petugas perpustakaan. Sebagian besar informan menyatakan bahwa masih ada petugas yang belum sadar dengan adanya peraturan dan nilai yang ada di dalam organisasi, hal itu menyebabkan waktu kerja petugas kurang efektif. Selain itu belum adanya pembagian kerja yang jelas juga menyebabkan proses penambahan kuantitas (dalam hal ini teknologi) tidak berjalan maksimal. Meskipun demikian, petugas selalu berusaha memberikan kualitas kerja yang baik kepada masyarakat serta tetap menjaga profesionalisme kerja dengan kerjasama yang baik sehingga lingkungan kerja menjadi tetap nyaman dan kondusif

Analisis Pembentukan Portofolio Optimal Saham Perusahaan Indeks Sri Kehati-bei Menggunakan Model Indeks Tunggal (2013-2015)

This research aims to know: 1) the company's stock in the Sri Kehati Index that form the optimal portfolio using Single Index Model; 2) the right proportion of funds for each stock which form an optimal portfolio; 3) the amount of expected return and risk are resulting from the optimal portfolio formation. The kind of research used in this research is descriptive research with a quantitative approach. The population used in this research are all of company's stock in the Sri Kehati Index period 2013-2015. The stock sampled in this research are 19 stocks. The results of this research showed that of the 19 stocks were sampled, there are only four stocks which form an optimal portfolio. The stocks which form an optimal portfolio are UNVR (64,48%), PJAA (21,85%), BBRI (11,77%) and BBCA (1,90%). The optimal portfolio formation resulting 2,4758% of expected return at 0,0885% level of risk

Left ear advantage in speech-related dichotic listening is not specific to auditory processing disorder in children: A machine-learning fMRI and DTI study

AbstractDichotic listening (DL) tests are among the most frequently included in batteries for the diagnosis of auditory processing disorders (APD) in children. A finding of atypical left ear advantage (LEA) for speech-related stimuli is often taken by clinical audiologists as an indicator for APD. However, the precise etiology of ear advantage in DL tests has been a source of debate for decades. It is uncertain whether a finding of LEA is truly indicative of a sensory processing deficit such as APD, or whether attentional or other supramodal factors may also influence ear advantage. Multivariate machine learning was used on diffusion tensor imaging (DTI) and functional MRI (fMRI) data from a cohort of children ages 7–14 referred for APD testing with LEA, and typical controls with right-ear advantage (REA). LEA was predicted by: increased axial diffusivity in the left internal capsule (sublenticular region), and decreased functional activation in the left frontal eye fields (BA 8) during words presented diotically as compared to words presented dichotically, compared to children with right-ear advantage (REA). These results indicate that both sensory and attentional deficits may be predictive of LEA, and thus a finding of LEA, while possibly due to sensory factors, is not a specific indicator of APD as it may stem from a supramodal etiology