On the Noisy Feedback Capacity of Gaussian Broadcast Channels

It is well known that, in general, feedback may enlarge the capacity region of Gaussian broadcast channels. This has been demonstrated even when the feedback is noisy (or partial-but-perfect) and only from one of the receivers. The only case known where feedback has been shown not to enlarge the capacity region is when the channel is physically degraded (El Gamal 1978, 1981). In this paper, we show that for a class of two-user Gaussian broadcast channels (not necessarily physically degraded), passively feeding back the stronger user's signal over a link corrupted by Gaussian noise does not enlarge the capacity region if the variance of feedback noise is above a certain threshold.Comment: 5 pages, 3 figures, to appear in IEEE Information Theory Workshop 2015, Jerusale

Lesions mimicking lacrimal gland pleomorphic adenoma

Aim: To report a series of patients with lacrimal gland lesions simulating the clinicoradiological features of lacrimal gland pleomorphic adenoma (LGPA). Methods: Multicentre retrospective, interventional case series. Clinical records of all patients with lesions mimicking LGPA seen in five orbital units were reviewed. Results: The study included 14 patients (seven men and seven women) with a mean age of 50.9 years. The diagnosis of LGPA was made in all cases by experienced orbital surgeons, based on clinicoradiological features, and lacrimal gland excision was performed. Postoperative histology revealed lymphoma (four patients), chronic dacryoadenitis (three patients), adenoid cystic carcinoma (two patients), Sjogren's syndrome (two patients), cavernous haemangioma (one patient), benign lymphoid hyperplasia (one patient) and granulomatous dacryoadenitis (one patient). Comparison with the total number of histologically confirmed LGPA cases seen during the study period revealed that 22.6% of cases of suspected LGPA were misdiagnosed based on clinicoradiological criteria. Conclusions: Many different lesions may mimic the clinicoradiological features of LGPA. The accepted clinicoradiological criteria used for the diagnosis of LGPA have a high false-positive rate, even in experienced hands. Based on this study, the authors believe that fine-needle aspiration biopsy or intraoperative biopsy and frozen section diagnosis may help reduce unnecessary lacrimal gland excision.Venkatesh C Prabhakaran, Paul S Cannon, Alan McNab, Garry Davis, Brett O’Donnell, Peter J Dolman, Raf Ghabrial, Dinesh Selv

A high resolution, hard x-ray photoemission investigation of La_(2-2x)Sr_(1+2x)Mn_2O_7 (0.30<x<0.50): on microscopic phase separation and the surface electronic structure of a bilayered CMR manganite

Photoemission data taken with hard x-ray radiation on cleaved single crystals of the bilayered, colossal magnetoresistant manganite La_(2-2x)Sr_(1+2x)Mn_2O_7 (LSMO) with 0.30<x<0.50 are presented. Making use of the increased bulk-sensitivity upon hard x-ray excitation it is shown that the core level footprint of the electronic structure of the LSMO cleavage surface is identical to that of the bulk. Furthermore, by comparing the core level shift of the different elements as a function of doping level x, it is shown that microscopic phase separation is unlikely to occur for this particular manganite well above the Curie temperature.Comment: 7 pages, 5 figure

Cephalopod resources revealed by exploratory surveys in Indian seas

The areawise and depth wise cephalopod catches of fishing vessels of Government of India and some Agencies which conducted exploratory fishing in offshore areas have been presented and discussed. The exploratory fishing by Government of India vessels in Bombay-Gujarat region during 1977-80 yielded a maximum of 7,609 kg of cephalopods a year at a catch rate of 6.8 kg/h. The highest catch rates were recorded from the area 19-70 and the depth zone 80-89 m. In Visakhapatnam region the cephalopod catch was poor during 1968-75 but during 1977-80 the annual catch increased to 3,283 kg. The most intensively fished area was 17-83. The catch was composed of four species of cuttlefishes and three species of squids. The results of trawl surveys in other parts of Indian waters are also dealt with

Hukum, Profesi Jurnalistik Dan Etika Media Massa

Dalam kajian hukum dan media massa, moral dan etika tersebut dikaitkan pada kewajiban para jurnalistik antara lain seperti; pelaksanaan kode etik jurnalistik dalam setiap aktivitas jurnalistiknya, tunduk pada institusi dan peraturan hukum untuk melaksanakan dengan etiket baiknya sebagaimana ketentuan-ketentuan di dalam hukum tersebut yang merupakan perangkat prinsip-prinsip dan aturan-aturan yang pada umumnya sudah diterima dan disetujui oleh masyarakat. Sehubungan dengan hal itu, prinsip etika bagi profesi jurnalistik memberikan dasar hukum bagi pengelolaan pemberitaan di media secara tertib dalam hubungan antar subyek hukum.Pada perkembangan di institusi media di Indonesia, aspek kepemilikan saham di media (kepemimpinan), ekonomi dan pemasaran media akan sangat menentukan ideologi yang diusung media, di mana ideologi tersbeut jika mengarah pada pendekatan ekonomi politik media akan memunculkan pelaku media yang kurang akrab dengan etika komunikasi. Etika komunikasi di sini ditempatkan hanya sebagai instrumen belaka dan menjadi kurang bermakna dalam menentukan isi program, kualitas program serta penghormatan pelaku media terhadap hak asasi manusia yang direpresentasikan pada individu sebagai sumber informasi. Pilihan ini menimbulkan etika komunikasi pada pelaku media dianggap sudah mengalami reduksi. Pelaku media sebagai profesi telah mengambil jalan pintas dengan mengacu asas manfaat lebih mengutamakan asas manfaat dalam peliputan dan pemberitaannya, yang sekaligus paradoks dengan etika profesi yang diembannya. Diperparah lagi ketiadaan penghormatan atas asas praduga tak bersalah atas nama demi kepentingan publik untuk memperoleh informasi, akan semakin menjadikan media massa dan pelaku media sebagai pribadi-pribadi yang dominan dalam merekonstruksi dan memanipulasi realitas sosial.Hingga di sini pilihan terhadap kecenderungan pemaknaan pendekatan ekonomi politik atau pendekatan etika, sebenarnya keduanya tidak memiliki implikasi hukum yang kentara, semuanya dikembalikan kepada masing-masing pribadi yang terlibat dalam aktivitas di institusi media massa

On the Communication Complexity of Secure Computation

Information theoretically secure multi-party computation (MPC) is a central primitive of modern cryptography. However, relatively little is known about the communication complexity of this primitive. In this work, we develop powerful information theoretic tools to prove lower bounds on the communication complexity of MPC. We restrict ourselves to a 3-party setting in order to bring out the power of these tools without introducing too many complications. Our techniques include the use of a data processing inequality for residual information - i.e., the gap between mutual information and G\'acs-K\"orner common information, a new information inequality for 3-party protocols, and the idea of distribution switching by which lower bounds computed under certain worst-case scenarios can be shown to apply for the general case. Using these techniques we obtain tight bounds on communication complexity by MPC protocols for various interesting functions. In particular, we show concrete functions that have "communication-ideal" protocols, which achieve the minimum communication simultaneously on all links in the network. Also, we obtain the first explicit example of a function that incurs a higher communication cost than the input length in the secure computation model of Feige, Kilian and Naor (1994), who had shown that such functions exist. We also show that our communication bounds imply tight lower bounds on the amount of randomness required by MPC protocols for many interesting functions.Comment: 37 page

The co-occurrence of anemia and cardiometabolic disease risk demonstrates sex-specific sociodemographic patterning in an urbanizing rural region of southern India.

BACKGROUND/OBJECTIVES: To determine the extent and sociodemographic determinants of anemia, overweight, metabolic syndrome (MetS) and the co-occurrence of anemia with cardiometabolic disease risk factors among a cohort of Indian adults. SUBJECT/METHODS: Cross-sectional survey of adult men (n=3322) and nonpregnant women (n=2895) aged 18 years and older from the third wave of the Andhra Pradesh Children and Parents Study that assessed anemia, overweight based on body mass index, and prevalence of MetS based on abdominal obesity, hypertension and blood lipid and fasting glucose measures. We examined associations of education, wealth and urbanicity with these outcomes and their co-occurrence. RESULTS: The prevalence of anemia and overweight was 40% and 29% among women, respectively, and 10% and 25% among men (P<0.001), respectively, whereas the prevalence of MetS was the same across sexes (15%; P=0.55). The prevalence of concurrent anemia and overweight (9%), and anemia and MetS (4.5%) was highest among women. Household wealth was positively associated with overweight and MetS across sexes (P<0.05). Independent of household wealth, higher education was positively correlated with MetS among men (odds ratio (95% confidence interval): MetS: 1.4 (0.99, 2.0)) and negatively correlated with MetS among women (MetS: 0.54 (0.29, 0.99)). Similar sex-specific associations were observed for the co-occurrence of anemia with overweight and MetS. CONCLUSIONS: Women in this region of India may be particularly vulnerable to co-occurring anemia and cardiometabolic risk, and associated adverse health outcomes as the nutrition transition advances in India

On the weak confinement of kinks in the one-dimensional quantum ferromagnet CoNb2O6

In a recent paper Coldea et al (2010 Science {\bf 327} 177) report observation of the weak confinement of kinks in the Ising spin chain ferromagnet CoNb2O6 at low temperatures. To interpret the entire spectra of magnetic excitations measured via neutron scattering, they introduce a phenomenological model, which takes into account only the two-kink configurations of the spin chain. We present the exact solution of this model. The explicit expressions for the two-kink bound-state energy spectra and for the relative intensities of neutron scattering on these magnetic modes are obtained in terms of the Bessel function.Comment: 18 pages, 9 figures; v2: figures 1,3,4 replaced, few misprints correcte

Deep generative modeling for single-cell transcriptomics.

Single-cell transcriptome measurements can reveal unexplored biological diversity, but they suffer from technical noise and bias that must be modeled to account for the resulting uncertainty in downstream analyses. Here we introduce single-cell variational inference (scVI), a ready-to-use scalable framework for the probabilistic representation and analysis of gene expression in single cells ( https://github.com/YosefLab/scVI ). scVI uses stochastic optimization and deep neural networks to aggregate information across similar cells and genes and to approximate the distributions that underlie observed expression values, while accounting for batch effects and limited sensitivity. We used scVI for a range of fundamental analysis tasks including batch correction, visualization, clustering, and differential expression, and achieved high accuracy for each task