Cover Article Research Articles, Systems/Circuits

Double cones are the most common photoreceptor cell type in most avian retinas, but their precise functions remain a mystery. Among their suggested functions are luminance detection, polarized light detection, and light-dependent, radical-pair-based magnetoreception. To better understand the function of double cones, it will be crucial to know how they are connected to the neural network in the avian retina. Here we use serial sectioning, multi-beam scanning electron microscopy (ssmSEM) to investigate double cone anatomy and connectivity with a particular focus on their contacts to other photoreceptor and bipolar cells in the chicken retina. We found that double cones are highly connected with neighbouring double cones and with other photoreceptor cells through telodendria-to-terminal and telodendria-to-telodendria contacts. We also identified 15 bipolar cell types based on their axonal stratifications, photoreceptor contact pattern, soma position, and dendritic and axonal field mosaics. Thirteen of these 15 bipolar cell types contacted at least one or both members of the double cone. All bipolar cells were bi- or multistratified. We also identified surprising contacts between other cone types and between rods and cones. Our data indicate a much more complex connectivity network in the outer plexiform layer of the avian retina than originally expected

Analisi aperlindungan Hukum Pemegang Saham Minorotas Oleh Emiten Berdasarkan Undang-Undang Nomor 8 Tahun 1995 tentang Pasar Modal

Perlindunga hukum terhadap pemegang saham minoritas didalam Pasar Modal merupakan hal yang sangat penting terlebih terhadap keterbukaan informasi yang terdapat di dalam Pasal 1 butir 25 Undang-Undang Nomor 8 Tahun 1995 tentang Pasar Modal. Adapun tujuan dari penulisan ini adalah: untuk mengetahui bagaimana perlindungan hukum dan tanggung jawab emiten terhadap pemegang saham minoritas berdasarkan prinsip keterbukaan yang ada di dalam Undang-Undang Nomor 8 Tahun 1995 Tentang Pasar Modal, dan juga penegakan hukum atau sanksi kepada pihak yang melakukan pelanggaran terhadap prinsip keterbukaan di dalam ketentuan tersebut. Metode penelitian yang digunakan dalam penulisan ini adalah jenis penelitian hukum yuridis-normatif. Yuridis-normatif adalah penelitian dengan pendekatan perundang-undangan dimana dalam hal ini Undang-Undang Nomor 8 Tahun 1995 tentang Pasar Modal. Hasil dari penelitian mengenai perlindungan hukum terhadap pemegang saham minoritas atas kerugian akibat tidak adanya keterbukaan informasi di Pasar Modal berdasarkan prinsip keterbukaan yang terdapat pada Pasal 1 butir 25 Undang_Undang Nomor 8 Tahun 1998 tentang Pasar Modal. dalam hal kerugian akibat tidak adanya keterbukaan infomasi yang dialami oleh invertor menjadi tanggung jawab Emiten sepenuhnya, dan pemegang saham yang mengalami kerugian berhak mendapat ganti rugi, dan investor yang menderita kerugian dapat melakukan upaya hukum berdasarkan perbuatan melawan hukum Pasal 1365 BW dan dapat melakukan gugatan berdasarkan Pasal 111 UUPM, juga dapat melakukan gugatan wanprestasi. Disarankan untuk dapat melakuakn rivisi terhadap UUPM dimana dalam hal ini UUPM tidah menjelaskan pengaturan secara spesifik mengenai, tanggung jawab emiten terhadap pemegang saham minoritas, maka harus dilakaukan revisi terhadap UUPM dan UUPM harus menyebukan pasal yang mengatur secara spesifik tentang tanggung jawab emiten terhadap pemegang saham minoritas. Agar dapat menjamin hak-hak pemegang saham minoritas apaliba terjadi kerugian yang diakibatkan oleh tidak berjalannya prinsip keterbukaan didalam Pasar Modal

First Measurement of the Transverse Spin Asymmetries of the Deuteron in Semi-Inclusive Deep Inelastic Scattering

First measurements of the Collins and Sivers asymmetries of charged hadrons produced in deep-inelastic scattering of muons on a transversely polarized 6-LiD target are presented. The data were taken in 2002 with the COMPASS spectrometer using the muon beam of the CERN SPS at 160 GeV/c. The Collins asymmetry turns out to be compatible with zero, as does the measured Sivers asymmetry within the present statistical errors.Comment: 6 pages, 2 figure

The Polarised Valence Quark Distribution from semi-inclusive DIS

The semi-inclusive difference asymmetry A^{h^{+}-h^{-}} for hadrons of opposite charge has been measured by the COMPASS experiment at CERN. The data were collected in the years 2002-2004 using a 160 GeV polarised muon beam scattered off a large polarised ^6LiD target and cover the range 0.006 < x < 0.7 and 1 < Q^2 < 100 (GeV/c)^2. In leading order QCD (LO) the asymmetry A_d^{h^{+}-h^{-}} measures the valence quark polarisation and provides an evaluation of the first moment of Delta u_v + Delta d_v which is found to be equal to 0.40 +- 0.07 (stat.) +- 0.05 (syst.) over the measured range of x at Q^2 = 10 (GeV/c)^2. When combined with the first moment of g_1^d previously measured on the same data, this result favours a non-symmetric polarisation of light quarks Delta u-bar = - Delta d-bar at a confidence level of two standard deviations, in contrast to the often assumed symmetric scenario Delta u-bar = Delta d-bar = Delta s-bar = Delta s.Comment: 7 pages, 3 figures, COMPASS, revised: details added, author list update

The COMPASS Experiment at CERN

The COMPASS experiment makes use of the CERN SPS high-intensitymuon and hadron beams for the investigation of the nucleon spin structure and the spectroscopy of hadrons. One or more outgoing particles are detected in coincidence with the incoming muon or hadron. A large polarized target inside a superconducting solenoid is used for the measurements with the muon beam. Outgoing particles are detected by a two-stage, large angle and large momentum range spectrometer. The setup is built using several types of tracking detectors, according to the expected incident rate, required space resolution and the solid angle to be covered. Particle identification is achieved using a RICH counter and both hadron and electromagnetic calorimeters. The setup has been successfully operated from 2002 onwards using a muon beam. Data with a hadron beam were also collected in 2004. This article describes the main features and performances of the spectrometer in 2004; a short summary of the 2006 upgrade is also given.Comment: 84 papes, 74 figure

Gluon polarization in the nucleon from quasi-real photoproduction of high-pT hadron pairs

We present a determination of the gluon polarization Delta G/G in the nucleon, based on the helicity asymmetry of quasi-real photoproduction events, Q^2<1(GeV/c)^2, with a pair of large transverse-momentum hadrons in the final state. The data were obtained by the COMPASS experiment at CERN using a 160 GeV polarized muon beam scattered on a polarized 6-LiD target. The helicity asymmetry for the selected events is = 0.002 +- 0.019(stat.) +- 0.003(syst.). From this value, we obtain in a leading-order QCD analysis Delta G/G=0.024 +- 0.089(stat.) +- 0.057(syst.) at x_g = 0.095 and mu^2 =~ 3 (GeV}/c)^2.Comment: 10 pages, 3 figure

The Deuteron Spin-dependent Structure Function g1d and its First Moment

We present a measurement of the deuteron spin-dependent structure function g1d based on the data collected by the COMPASS experiment at CERN during the years 2002-2004. The data provide an accurate evaluation for Gamma_1^d, the first moment of g1d(x), and for the matrix element of the singlet axial current, a0. The results of QCD fits in the next to leading order (NLO) on all g1 deep inelastic scattering data are also presented. They provide two solutions with the gluon spin distribution function Delta G positive or negative, which describe the data equally well. In both cases, at Q^2 = 3 (GeV/c)^2 the first moment of Delta G is found to be of the order of 0.2 - 0.3 in absolute value.Comment: fits redone using MRST2004 instead of MRSV1998 for G(x), correlation matrix adde