477 research outputs found
A star-forming galaxy at z= 5.78 in the Chandra Deep Field South
Get PDFWe report the discovery of a luminous z = 5.78 star-forming galaxy in the Chandra Deep Field South. This galaxy was selected as an ‘i-drop’ from the GOODS public survey imaging with the Hubble Space Telescope/Advanced Camera for Surveys (object 3 in the work of Stanway, Bunker & McMahon 2003). The large colour of (i′−z′)AB = 1.6 indicated a spectral break consistent with the Lyman α forest absorption shortward of Lyman α at z≈ 6. The galaxy is very compact (marginally resolved with ACS with a half-light radius of 0.08 arcsec, so rhl 5. Our spectroscopic redshift for this object confirms the validity of the i′-drop technique of Stanway et al. to select star-forming galaxies atz≈ 6
Negatively supercharging cellulases render them lignin-resistant
No full textNon-specific adsorption of cellulases to lignin hinders enzymatic deconstruction of lignocellulosic biomass. Here we tested the hypothesis that negatively supercharging cellulases could reduce lignin inhibition. Computational design was used to negatively supercharge the surfaces of Ruminoclostridium thermocellum family 5 CelE and a CelE-family 3a carbohydrate binding module fusion. Resulting designs maintained the same expression yield, thermal stability, and nearly identical activity on soluble substrate as the wild-type proteins. Four designs showed complete lack of inhibition by lignin but with lower cellulose conversion compared to original enzymes. Increasing salt concentrations could partially rescue the activity of supercharged enzymes, supporting a mechanism of electrostatic repulsion between designs and cellulose. Results showcase a protein engineering strategy to construct highly active cellulases that are resistant to lignin-mediated inactivation, although further work is needed to understand the relationship between negative protein surface potential and activity on insoluble polysaccharides.Peer reviewe
Support Recovery from Linear Measurements: Tradeoffs in the Measurement-Constrained Regime
No full textIn this thesis, we study problems under the theme of discovering joint sparsity structure in a set of high-dimensional data samples from linear measurements. Our primary focus is on the regime where the number of samples available can potentially be large, but we are constrained to access very few measurements per sample. This setting can be used model high-dimensional estimation tasks in a distributed setting, where storing or communicating more measurements per sample can be expensive.
We first study a basic problem in this setting -- that of support recovery from linear measurements. In this problem, a set of n samples in d-dimensional Euclidean space, each having a support of size k, is accessed through m linear measurements per sample. The goal is to recover the unknown support, given knowledge of the m-dimensional measurements and the corresponding measurement matrices. This problem, also sometimes referred to as variable selection or model selection, has been extensively studied in the signal processing and statistics literature, and finds applications in source localization, hyperspectral imaging, heavy hitters detection in networks, and feature selection in regression. It is known that if we have m=\Omega(k \log d) measurements per sample, then even a single sample is sufficient for support recovery. As such, when we have access to multiple samples, an interesting question is whether we can perform recovery with fewer than k measurements per sample. This measurement-constrained setting is relatively less explored in the literature, and the optimal sample-measurement tradeoff was unknown prior to our work.
We provide a tight characterization of the sample complexity of this problem, which together with previous results in the literature gives a full understanding of the scaling laws of this problem for different values of the ratio k/m. We propose two algorithms that can perform recovery in the measurement-constrained regime, where standard algorithms fail to work. Our first algorithm is a simple closed-form variance estimation-based procedure, while our second algorithm is based on an approximate maximum likelihood procedure. We show that when m<k, the minimum number of samples required for exact support recovery with high probability scales as \Theta((k^2/m^2)\log d). Our upper bound is obtained by analyzing the closed-form estimator and holds for the class of subgaussian samples and subgaussian measurement matrices chosen independently across samples. Our lower bound construction uses Gaussian samples and Gaussian measurement matrices.
In the second part of the thesis, we show that the upper bound result for the closed-form estimator extends to worst-case inputs, thus demonstrating that the case of Gaussian inputs is the hardest for this problem. In addition, our analysis reveals a phase transition for the problem of support recovery at k/m=1. In this way, our result demonstrates that when m<k, multiple measurements from the same sample are more valuable than measurements from different samples. In our analysis for this worst-case inputs setting, we provide some useful results in the form of concentration bounds for heavy-tailed random variables, which may find use in other problems as well.
In the third part of the thesis, we consider the extension of the problem to the case of multiple disjoint supports, where the support of each sample is assumed to be one out of a small set of a constant number of allowed supports, each of size k. We propose a two-step algorithm for this setting, that first estimates the union of the underlying supports, and then estimates the individual supports using a spectral algorithm. We analyze this algorithm for the class of subgaussian inputs and measurement matrices, and show an upper bound of O(k^4/m^4), up to polylogarithmic factors in the problem dimensions, on the sample complexity of this problem when m<k
Application Portfolio STMIK Jakarta Campus STI & K Using Macromedia Flash 8.0
Get PDFScientific writing is about a Portfolio Application Campus STMIK STI & K. Jakarta To Create Multimedia Animation. This application was created to provide information to users in order to simplify the familiar campus STMIK STI & K. Jakarta In scientific writing, Multimedia Applications To Create Animations author using Macromedia Flash 8.0 which will support the presentation of learning methods in these applications include the use of writing and moving images. thus can be expected to attract more users in identifying campus STMIK STI & K. Jakart
ALUMNI DATA PROCESSING APPLICATIONS STMIK JAKARTA STI & K USING MICROSOFT VISUAL FoxPro 9.0
No full textAbstract :This explains the scientific writing about the Application of Data Processing Alumni JAKARTA STMIK STI & K by using Microsoft Visual FoxPro 9.0. Where an existing application has a menu that has not been integrated and enhanced by the author with this application. The data in this application obtained through a form that is spread by the Institute of Development Computerization (LPK) JAKARTA STMIK STI & K section Career Services Center (Carreer Center) to alumni. Alumni who referred to here are students who Three have passed the Diploma session or Strata One. In this application, alumni data that has not worked can be processed into a file Microsoft Office Excel, where the files are requested by the company Three graduate diploma requires a person or Strata One with various criteria are needed so that graduates can obtain employment information. Ultimately Applications of Data Processing Alumni STMIK JAKARTA STI & K This will be applied on Computerization Development Institute (LPK) STMIK JAKARTA STI & K the Career Services Center (Carreer Center) to accommodate alumni data and simplify the service vacancies informationjobs for alumni
Control under communication constraints
No full textThesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000.Includes bibliographical references (p. 224-228).This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.by Sekhar Chandra Tatikonda.Ph.D
Radio sources in the Chandra Galactic Bulge Survey
Get PDFWe discuss radio sources in the Chandra Galactic Bulge Survey region. By cross-matching the X-ray sources in this field with the NRAO VLA Sky Survey archival data, we find 12 candidate matches. We present a classification scheme for radio/X-ray matches in surveys taken in or near the Galactic plane, taking into account other multiwavelength data. We show that none of the matches found here is likely to be due to coronal activity from normal stars because the radio to X-ray flux ratios are systematically too high. We show that one of the source could be a radio pulsar, and that one could be a planetary nebula, but that the bulk of the sources are likely to be background active galactic nuclei (AGN), with many confirmed through a variety of approaches. Several of the AGN are bright enough in the near-infrared (and presumably in the optical) to use as probes of the interstellar medium in the inner Galaxy
Alumni Data Processing Applications STMIK Jakarta STI & K Using Microsoft Visual Foxpro 9.0
Get PDFThis explains the scientific writing about the Application of Data Processing Alumni JAKARTA STMIK STI & K by using Microsoft Visual FoxPro 9.0. Where an existing application has a menu that has not been integrated and enhanced by the author with this application. The data in this application obtained through a form that is spread by the Institute of Development Computerization (LPK) JAKARTA STMIK STI & K section Career Services Center (Carreer Center) to alumni. Alumni who referred to here are students who Three have passed the Diploma session or Strata One. In this application, alumni data that has not worked can be processed into a file Microsoft Office Excel, where the files are requested by the company Three graduate diploma requires a person or Strata One with various criteria are needed so that graduates can obtain employment information. Ultimately Applications of Data Processing Alumni STMIK JAKARTA STI & K This will be applied on Computerization Development Institute (LPK) STMIK JAKARTA STI & K the Career Services Center (Carreer Center) to accommodate alumni data and simplify the service vacancies informationjobs for alumni
SPARSE SUPPORT RECOVERY VIA COVARIANCE ESTIMATION
No full textWe consider the problem of recovering the common support of a set of k-sparse signals {X-i}(i=1)(L) from noisy linear under-determined measurements of the form {Phi X-i + w(i)}(i=1)(L) where Phi is an element of R-mxN (m < N) is the sensing matrix and w(i )is the additive noise. We employ a Bayesian setup where we impose a Gaussian prior with zero mean and a common diagonal covariance matrix Gamma across all x(i), and formulate the support recovery problem as one of covariance estimation. We develop an algorithm to find the approximate maximum-likelihood estimate of Gamma using a modified reweighted minimization procedure. Empirically, we find that the proposed algorithm succeeds in exactly recovering the common support with high probability in the k < m regime with L of the order of m and in the k >= m regime with larger L. The key advantage of the proposed algorithm is that its complexity is independent of L, unlike existing sparse support recovery algorithms
Odontotrypes (Odontotrupes) tawangensis Gupta, Chandra & Hillert, 2016, new species
No full text<i>Odontotrypes</i> (<i>Odontotrupes</i>) <i>tawangensis</i> new species <p>(Figs. 1–19)</p> <p> <b>Type locality.</b> India, Arunachal Pradesh state, Tawang district.</p> <p> <b>Type material.</b> 18 specimens: holotype male labeled: “ India, Arunachal Pradesh state, Tawang district / Sela / 27.523491N, 92.106493E / 5.x.2010 / collected K. Chandra ” in ZSCI [ZSI Registration Number: 21489/H4A]. Allotype female labeled: “NE INDIA W, ARUNACHAL PR / TAWANG Monastery vicinity / 27°35´30´´N 91°51´E; 2700–3000 m / 19.-27.v. 2004 ” in SJCP. Paratypes: “ India, Arunachal Pradesh state / Tawang district / Sela 27.523491N, 92.106493E / 5.x.2010 / collected K. Chandra ” 1 male in ZSCI [ZSI Registration Number: 21490/H4A]; “NE INDIA W, ARUNACHAL PR / TAWANG Monastery vicinity / 27°35´30´´N 91°51´E; 2700– 3000 m / 19.-27.v. 2004 ” 1 male in DKCP, 1 male and 1 female in JSCP, 6 males and 4 females in SJCP, 1 male and 1 female in OHCB.</p> <p> <b>Description of holotype</b> (Fig. 1). Length 20.0 mm, maximum width 9.7 mm, oblong and convex. Dorsally black; vertex and elytra at base with metallic luster; ventral surface black with cuprous tinge especially on mesofemora, metafemora, and anterior part of pronotum.</p> <p>Head (Figs. 2, 4): Labrum truncate anteriorly. Anterior clypeal margin broadly arcuate, clypeal disc distinctly elevated in middle, clypeal surface slightly rugopunctate near lateral margins, elevated areas smooth; area around frontoclypeal junction distinctly depressed, T-shaped, suture distinct. Median suture on vertex indistinct; eye tubercle blunt and distinctly prominent dorsally, in lateral view angular; eye canthus smooth.</p> <p>Pronotum (Figs. 3, 5): Transverse, broadest just posteriad of middle; completely bordered (finely at base); lateral margins rounded, not crenulate; anterior marginal carina moderately elevated and widened in middle. Anterior angles blunt, broadly rounded, sides almost straight in anterior third forming a rounded lateral angle; posterior angles bent 45°. Surface completely smooth in middle with few scattered punctures; anterior concavity reduced, simple depression; lateral fovea small with rugopunctation; surface near lateral margins rugopunctate anteriorly and posteriorly.</p> <p>Scutellum (Fig. 7): Pentagonal, basal margin not bordered, slightly declined inward, surface entirely smooth, yellow border present at each side from meeting point to base.</p> <p>Elytra (Fig. 6): Humeral umbone weakly prominent; base almost equal in length to pronotum, neither margined nor carinate; surface glabrous. Surface with 7 distinct striae clearly indicated between suture and humeral umbone, which gradually disappear towards apex; intervals 3–7 convex and impunctate; lateral side with a continuous carina from humeral umbone to apex.</p> <p>Legs (Figs. 8–9): Profemora black, not shiny, completely smooth; mesofemora and metafemora shiny with 2 rows of setose punctures. Protibiae laterally with 5 teeth including 4 distinct anterior teeth, and 1 weak basal tooth (Fig. 8); on ventral side medially with 7 teeth including 3 anterior, sharp, distinct teeth and 4 blunt, reduced teeth (Fig 9).</p> <p>Macropterous (Fig. 10).</p> <p>Abdominal ventrites shiny, serrate punctate.</p> <p>Aedeagus as in Figs. 11–13 (holotype) and 16–17 (paratypes: India, Arunachal Pradesh, Tawang Monastery vicinity, in DKCP).</p> <p>Measurements (mm): Median length of head (excluding labrum and mandibles) 3.1, distance between frontal tubercles 2.9, anterior margin of clypeus (circumference) 4.1, median length of pronotum (dorsal) 5.3, maximum width 9.6, median length of scutellum 1.3, maximum width 1.7, sutural length of elytra (dorsal) 9.2, maximum width combined 9.7, aedeagus (length) 3.7.</p> <p> <b>Variation</b>. Length 17.0–20.0 mm, width 8.5–9.7 mm. The female differs from male by the less developed clypeal tubercle and the weaker protibial teeth.</p> <p> <b>Distribution</b>. Only known from type locality: Sela, Tawang, Arunachal Pradesh, India (Fig. 15).</p> <p> <b>Etymology.</b> The name <i>tawangensis</i> refers to the type locality of this species, the Tawang district of the state of Arunachal Pradesh.</p> <p> <b>Differential diagnosis.</b> <i>Odontotrypes</i> (<i>Odontotrupes</i>) <i>tawangensis</i> new species is distinguished from the closely related species <i>O</i>. (<i>O</i>.) <i>orichalceus</i> (reported from the Tibetan Plateau of Sikkim) by the unique structure of the aedeagus (Figs. 11–13, 16–17) (right paramere with distinct internal truncate appendix situated subapically and directed inward) and the structure of the elytra (elytral striae are distinct basally, becoming more shallowly apically), and the well-developed metathoracic wings. Based on the keys given by Král <i>et al.</i> (2001) <i>Odontotrypes</i> (<i>O.</i>) <i>tawangensis</i> should be classified in the subgenus <i>Odontotrupes</i>. Species of this subgenus that are distributed in Bhutan and India characteristically have slightly reduced or normal-sized metathoracic wings, namely <i>O.</i> (<i>O.</i>) <i>bhutan</i>, <i>O.</i> (<i>O.</i>) <i>gogona</i>, <i>O.</i> (<i>O.</i>) <i>orichalceus</i>, and <i>O.</i> (<i>O.</i>) <i>tawangensis</i>. According to Král <i>et al.</i> (2001) the distribution ranges of <i>Odontotrypes</i> are relatively small, many of them being endemic to single mountain systems, separated by deep river valleys.</p> <p>The authors wish to thank the director of the Zoological Survey of India, for providing them with the necessary facilities and for his encouragements. The first author is thankful to Paul Schoolmeesters (Belgium) for literature, Baiju Lal (former Officer-in-Charge, Coleoptera Section, Zoological Survey of India), Amitava Mujumder, and Joyjit Ghosh. We also thank Marc Miquel (Queen Mary University of London, United Kingdom) for editing our English text and review the earlier version of manuscript and Stanley Jákl, David Král, and Jan Schneider for access to the specimens examined.</p>Published as part of <i>Gupta, Devanshu, Chandra, Kailash & Hillert, Oliver, 2016, Odontotrypes (Odontotrupes) tawangensis new species (Coleoptera: Geotrupidae) from Arunachal Pradesh, India, pp. 559-566 in Zootaxa 4154 (5)</i> on pages 560-565, DOI: 10.11646/zootaxa.4154.5.4, <a href="http://zenodo.org/record/264799">http://zenodo.org/record/264799</a>
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