2,562 research outputs found

    Functional Subdomains within Human FFA

    Get PDF
    Cataloged from PDF version of article.The fusiform face area (FFA) is a well-studied human brain region that shows strong activation for faces. In functional MRI studies, FFA is often assumed to be a homogeneous collection of voxels with similar visual tuning. To test this assumption, we used natural movies and a quantitative voxelwise modeling and decoding framework to estimate category tuning profiles for individual voxels within FFA. We find that the responses in most FFA voxels are strongly enhanced by faces, as reported in previous studies. However, we also find that responses of individual voxels are selectively enhanced or suppressed by a wide variety of other categories and that these broader tuning profiles differ across FFA voxels. Cluster analysis of category tuning profiles across voxels reveals three spatially segregated functional subdomains within FFA. These subdomains differ primarily in their responses for nonface categories, such as animals, vehicles, and communication verbs. Furthermore, this segregation does not depend on the statistical threshold used to define FFA from responses to functional localizers. These results suggest that voxels within FFA represent more diverse information about object and action categories than generally assumed. © 2013 the authors

    Pengaruh Hambatan Samping Terhadap Kinerja Pada Ruas Jalan Panjaitan (Kelenteng Ban Hing Kiong) Dengan Menggunakan Metode Mkji 1997

    Get PDF
    Jalan merupakan prasarana transportasi darat yang memegang peranan penting dalam sektor perhubungan darat, dalam kehidupan masyarakat modern dengan berkembangnya teknologi, pertumbuhan ekonomi dan jumlah penduduk mengakibatkan banyaknya aktivitas kegiatan yang dilakukan, sedangkan kapasitas dan kinerja jalan yang menampung arus kendaraan, semakin terbatas. Pada kondisi ini sering menimbulkan kemacetan. Kinerja arus lalu lintas di daerah komersial menjadi berkurang, karena disebabkan oleh berbagai faktor yang terjadi pada sisi jalan. Salah satu faktor yang menyebabkan hal tersebut adalah aktifitas pada sisi jalan atau hambatan samping berupa kendaraan keluar masuk, penyeberang jalan, dan kendaraan lambat. Jalan Panjaitan khususnya depan kelenteng Ban Hing Kiong dipilih sebagai lokasi penelitian karena pada ruas jalan ini sering terjadi kemacetan yang diakibatkan oleh tingginya aktifitas sisi jalan berupa banyaknya kendaraan yang berhenti yang menaikkan dan menurunkan penumpang, parkir di badan jalan, penyeberang jalan, kendaraan tidak bermotor, kendaraan yang keluar masuk sisi jalan, yang mempengaruhi arus lalu lintas, kecepatan, kapasitas. Penelitian dilakukan selama 4 hari, yaitu pada hari Senin, Rabu, Jumat, dan Sabtu. Pengambilan data secara langsung dilapangan, untuk volume lalu lintas, kecepatan kendaraan dan data hambatan samping dibagi per 15 menit. Selanjutnya dilakukan analisa data yang dibagi dalam dua bagian yaitu volume lalu lintas, kecepatan, dan kapasitas jalan menggunakan Manual Kapasitas Jalan Indonesia (MKJI) Tahun 1997. Sedangkan untuk pengaruh hambatan samping terhadap kecepatan arus lalu lintas, dianalisa menggunakan regresi berganda dengan bantuan Microsoft Excel dengan cara menghilangkan salah satu faktor hambatan samping untuk mengetahui seberapa besar kontribusi masing-masing faktor hambatan samping terhadap kinerja arus lalu lintas. Hasil penelitian ini menunjukkan bahwa tingginya aktifitas sisi jalan atau hambatan samping cukup berpengaruh terhadap tingkat kinerja arus lalu lintas. Faktor hambatan samping yang sangat berpengaruh terhadap kecepatan arus lalu lintas adalah faktor kendaraan lambat 12.1 %, faktor penyeberang jalan 7.6 %, faktor kendaraan masuk dan keluar 5.5 %, faktor kendaraan berhenti 4.3 %, Selain itu diperoleh nilai kapasitas sebesar 1330.06 smp/jam, dengan derajat kejenuhan (DS) sebesar 0.986, Koefisien Determinasi (r) yang diperoleh dari hasil analisis yaitu sebesar 0.868, hal ini menunjukkan bahwa 86.8 % Perubahan variabel kendaraan keluar dan masuk penelitian, kendaraan berhenti, penyeberang jalan, dan kendaraan lambat secara bersama-sama mempengaruhi kecepatan arus lalu lintas

    MtDNA Analyses on Hair Samples Confirm Cougar, Puma concolor, Presence in Southern New Brunswick, Eastern Canada

    Get PDF
    For the last 40 years, the presence of Cougars (Puma concolor) in eastern Canada has been highly controversial. The purpose of this study was to collect physical evidence of Cougars using a passive detection method. Baited hair-traps combined with camera-traps were installed in New Brunswick and Nova Scotia, Canada. DNA analyses on two hair samples confirmed that the species was present in southern New Brunswick in 2003. A footprint photographed after an observation of a Cougar by reliable observers was examined by experts and was consistent with a Cougar footprint. Additional data are required to determine the status of Cougars in the northeastern part of its historical range

    Trapped-ion decay spectroscopy towards the determination of ground-state components of double-beta decay matrix elements

    Full text link
    A new technique has been developed at TRIUMF's TITAN facility to perform in-trap decay spectroscopy. The aim of this technique is to eventually measure weak electron capture branching ratios (ECBRs) and by this to consequently determine GT matrix elements of ββ\beta\beta decaying nuclei. These branching ratios provide important input to the theoretical description of these decays. The feasibility and power of the technique is demonstrated by measuring the ECBR of 124^{124}Cs.Comment: 9 pages, 9 figure

    Flecainide Paradoxically Activates Cardiac Ryanodine Receptor Channels under Low Activity Conditions: A Potential Pro-Arrhythmic Action.

    Get PDF
    Cardiac ryanodine receptor (RyR2) mutations are implicated in the potentially fatal catecholaminergic polymorphic ventricular tachycardia (CPVT) and in atrial fibrillation. CPVT has been successfully treated with flecainide monotherapy, with occasional notable exceptions. Reported actions of flecainide on cardiac sodium currents from mice carrying the pro-arrhythmic homozygotic RyR2-P2328S mutation prompted our explorations of the effects of flecainide on their RyR2 channels. Lipid bilayer electrophysiology techniques demonstrated a novel, paradoxical increase in RyR2 activity. Preceding flecainide exposure, channels were mildly activated by 1 mM luminal Ca2+ and 1 µM cytoplasmic Ca2+, with open probabilities (Po) of 0.03 ± 0.01 (wild type, WT) or 0.096 ± 0.024 (P2328S). Open probability (Po) increased within 0.5 to 3 min of exposure to 0.5 to 5.0 µM cytoplasmic flecainide, then declined with higher concentrations of flecainide. There were no such increases in a subset of high Po channels with Po ≥ 0.08, although Po then declined with ≥5 µM (WT) or ≥50 µM flecainide (P2328S). On average, channels with Po < 0.08 were significantly activated by 0.5 to 10 µM of flecainide (WT) or 0.5 to 50 µM of flecainide (P2328S). These results suggest that flecainide can bind to separate activation and inhibition sites on RyR2, with activation dominating in lower activity channels and inhibition dominating in more active channels

    Elevated Mechanical Loading When Young Provides Lifelong Benefits to Cortical Bone Properties in Female Rats Independent of a Surgically Induced Menopause

    Get PDF
    Exercise that mechanically loads the skeleton is advocated when young to enhance lifelong bone health. Whether the skeletal benefits of elevated loading when young persist into adulthood and after menopause are important questions. This study investigated the influence of a surgically induced menopause in female Sprague-Dawley rats on the lifelong maintenance of the cortical bone benefits of skeletal loading when young. Animals had their right forearm extrinsically loaded 3 d/wk between 4 and 10 weeks of age using the forearm axial compression loading model. Left forearms were internal controls and not loaded. Animals were subsequently detrained (restricted to cage activities) for 94 weeks (until age 2 years), with ovariectomy (OVX) or sham-OVX surgery being performed at 24 weeks of age. Loading enhanced midshaft ulna cortical bone mass, structure, and estimated strength. These benefits persisted lifelong and contributed to loaded ulnas having greater strength after detraining. Loading also had effects on cortical bone quality. The benefits of loading when young were not influenced by a surgically induced menopause because there were no interactions between loading and surgery. However, OVX had independent effects on cortical bone mass, structure, and estimated strength at early postsurgery time points (up to age 58 weeks) and bone quality measures. These data indicate skeletal loading when young had lifelong benefits on cortical bone properties that persisted independent of a surgically induced menopause. This suggests that skeletal loading associated with exercise when young may provide lifelong antifracture benefits by priming the skeleton to offset the cortical bone changes associated with aging and menopause

    Storage capacity of a constructive learning algorithm

    Full text link
    Upper and lower bounds for the typical storage capacity of a constructive algorithm, the Tilinglike Learning Algorithm for the Parity Machine [M. Biehl and M. Opper, Phys. Rev. A {\bf 44} 6888 (1991)], are determined in the asymptotic limit of large training set sizes. The properties of a perceptron with threshold, learning a training set of patterns having a biased distribution of targets, needed as an intermediate step in the capacity calculation, are determined analytically. The lower bound for the capacity, determined with a cavity method, is proportional to the number of hidden units. The upper bound, obtained with the hypothesis of replica symmetry, is close to the one predicted by Mitchinson and Durbin [Biol. Cyber. {\bf 60} 345 (1989)].Comment: 13 pages, 1 figur

    X-Ray Observations of the supernova remnant G21.5-0.9

    Full text link
    We present the analysis of archival X-ray observations of the supernova remnant (SNR) G21.5-0.9. Based on its morphology and spectral properties, G21.5-0.9 has been classified as a Crab-like SNR. In their early analysis of the CHANDRA calibration data, Slane et al. (2000) discovered a low-surface-brightness, extended emission. They interpreted this component as the blast wave formed in the supernova (SN) explosion. In this paper, we present the CHANDRA analysis using a total exposure of ~150 ksec. We also include ROSAT and ASCA observations. Our analysis indicates that the extended emission is non-thermal -- a result in agreement with XMM observations. The entire remnant of radius ~ 2'.5 is best fitted with a power law model with a photon index steepening away from the center. The total unabsorbed flux in the 0.5-10 keV is 1.1E-10 erg/cm2/s with an 85% contribution from the 40" radius inner core. Timing analysis of the High-Resolution Camera (HRC) data failed to detect any pulsations. We put a 16% upper limit on the pulsed fraction. We derive the physical parameters of the putative pulsar and compare them with those of other plerions (such as the Crab and 3C 58). G21.5-0.9 remains the only plerion whose size in X-rays is bigger than in the radio. Deep radio observations will address this puzzle.Comment: 23 pages including 11 figures and 3 tables; accepted by ApJ June 22, 2001; to appear in Oct 20, 2001 issue of Ap

    Modeling resilience and sustainability in ancient agricultural systems

    Get PDF
    The reasons why people adopt unsustainable agricultural practices, and the ultimate environmental implications of those practices, remain incompletely understood in the present world. Archaeology, however, offers unique datasets on coincident cultural and ecological change, and their social and environmental effects. This article applies concepts derived from ecological resilience thinking to assess the sustainability of agricultural practices as a result of long-term interactions between political, economic, and environmental systems. Using the urban center of Gordion, in central Turkey, as a case study, it is possible to identify mismatched social and ecological processes on temporal, spatial, and organizational scales, which help to resolve thresholds of resilience. Results of this analysis implicate temporal and spatial mismatches as a cause for local environmental degradation, and increasing extralocal economic pressures as an ultimate cause for the adoption of unsustainable land-use practices. This analysis suggests that a research approach that integrates environmental archaeology with a resilience perspective has considerable potential for explicating regional patterns of agricultural change and environmental degradation in the past
    corecore