3,052 research outputs found
Convertible Codes: New Class of Codes for Efficient Conversion of Coded Data in Distributed Storage
No full textErasure codes are typically used in large-scale distributed storage systems to provide durability of data in the face of failures. In this setting, a set of k blocks to be stored is encoded using an [n, k] code to generate n blocks that are then stored on different storage nodes. A recent work by Kadekodi et al. [Kadekodi et al., 2019] shows that the failure rate of storage devices vary significantly over time, and that changing the rate of the code (via a change in the parameters n and k) in response to such variations provides significant reduction in storage space requirement. However, the resource overhead of realizing such a change in the code rate on already encoded data in traditional codes is prohibitively high.
Motivated by this application, in this work we first present a new framework to formalize the notion of code conversion - the process of converting data encoded with an [n^I, k^I] code into data encoded with an [n^F, k^F] code while maintaining desired decodability properties, such as the maximum-distance-separable (MDS) property. We then introduce convertible codes, a new class of code pairs that allow for code conversions in a resource-efficient manner. For an important parameter regime (which we call the merge regime) along with the widely used linearity and MDS decodability constraint, we prove tight bounds on the number of nodes accessed during code conversion. In particular, our achievability result is an explicit construction of MDS convertible codes that are optimal for all parameter values in the merge regime albeit with a high field size. We then present explicit low-field-size constructions of optimal MDS convertible codes for a broad range of parameters in the merge regime. Our results thus show that it is indeed possible to achieve code conversions with significantly lesser resources as compared to the default approach of re-encoding
Artists’ Moving Image: South Asian Trajectories
No full textA special South Asia-focused journal edition of the journal, 'Moving Image Review and Art Journal'. The edition includes eight articles, features, reviews and interviews as well as a contextual preface by the editors, Lucia King and Rashmi Sawhney. Trajectories of film history and the practices of 'artists' moving image' makers from South Asia are traced and critiqued, including the significant impact of documentary film experimentation from the 1960s to the present. Author contributors are: Nancy Adajania, Avijit Mukul Kishore, Adnan Madani, Shai Heredia, Nicole Wolf, Kaushik Bhamik, Lucia King and Rashmi Sawhney
Figures 1-3. Xanthochelus superciliosus aedeagus. 1 in 'Retournement' of the aedeagus in Curculionidae (Coleoptera, Curculionoidea)
No full textFigures 1-3. Xanthochelus superciliosus aedeagus. 1) Aedeagal apparatus of adult in ventral view. The muscles GM1 and GM2 have been labeled following Burke (1959). 2) Basal part of the aedeagal apparatus in lateral view, from the right side. 3) Tracheal supply to the aedeagus base in ventral view.Published as part of Jolivet, Pierre, Verma, K. K. & Saxena, Rashmi, 2013, 'Retournement' of the aedeagus in Curculionidae (Coleoptera, Curculionoidea), pp. 1-5 in Insecta Mundi 2013 (300) on page 2, DOI: 10.5281/zenodo.517595
The small-scale approach in wastewater treatment
No full textThe wastewater treatment is an essential practice and is one of the forefront new
worldwide challenges. Indeed, the today aims in wastewater management are profoundly
changing. The sanitization processes are of course essential, but now some more efforts are
required not only to reduce the environmental impact of the effluent regarding the
receiving water body, for example in terms of organic load, but also to provide
management practices to allow water recovery, recycle and reuse. This means that treated
wastewater are new resources that may be reused according to their final level of quality.
New technological facilities are available about, some more are expected in the near future,
and innovative scaling approaches are strongly encouraged too. Actually, sometimes
extensive sewage collection systems are no more cost-effective, thus decentralisation
treatment processes considering small-scale wastewater treatment plants may represent a
potential solution in both developed and developing countries. Furthermore, this kind of
approach will strengthen those areas that are historically affected by drought phenomena or
are expected to suffer from water scarcities in the near future as a consequence of climate
change
VisionMix Artists, Filmmakers & Curators' Workshop
No full textA catalogue of a symposium and public film screening series held at the Goethe institute and Jawaharlal Nehru University, New Delhi. Curated by Lucia King as Founding Curator of the VisionMix international network of artists, curators and filmmakers. Co-author/curator and network Director, Rashmi Sawhney. Featuring programme details, contributors biographies and critical preface
Energy and emission impact quantification of pavement preservation using life cycle assessment
No full textThis study aims at developing a life cycle assessment (LCA) model to quantify the impact of pavement preservation on energy consumption and greenhouse gas (GHG) emissions. In the past, most of the research focused on the environmental impact of pavements at material and construction stages but ignored the usage stage. The construction stage analyzed in this study contains energy consumption and GHG emissions at material, manufacture, transportation and placement phases. Vehicle operating cost and fuel economy is affected by change in tire rolling resistance during usage stage. This also affects GHG emissions significantly. In this study the Highway Development and Management (HDM-4) model and the Motor Vehicle Emission Simulator (MOVES) were used to analyze fuel consumption and emissions caused by different vehicles on the pavements treated by different preservation treatments. Surface characteristics such as roughness, texture and deflection were taken into account in tire rolling resistance along with general factors such as speed, traffic volume, and road grade. Two pavement sections with different roughness from the long-term pavement performance (LTPP) database were used in the analysis to illustrate the importance of considering usage stage in LCA. The thin overlay was found to have the highest energy consumption and emissions among four preservation treatments during construction stage, but at the same time resulted in the greatest reduction of energy and emission at usage stage. If only construction stage is considered, energy and emissions are ruled by use of amount of material and manufacture process. The reductions of GHG emission at usage stage are much greater than the GHG emission produced at construction stage for all preservation treatments. Excluding the usage stage will omit the fact that construction stage has less impact on pavement LCA than usage stage. Combining both construction and usage stages gave a life-cycle impact of pavement preservation on energy and GHG emission. The results show that there is a significant amount of change in energy consumption and emissions when traffic factors and pavement surface characteristics are considered during usage stage. The study results provide valuable insights in selecting sustainable pavement maintenance strategies from an environmental view point.M.S.Includes bibliographical referencesby Rashmi Gangara
A new determination of molecular mobility in amorphous materials:
No full textThis research investigated how the steady-state and time-resolved emission and intensity of phosphorescence from vanillin (4-hydroxy-3-methoxy benzaldehyde), a commonly used flavor compound, can be used to probe molecular mobility when dispersed within amorphous pure sucrose films. The luminescence properties and photophysical events of vanillin as a triplet state probe in amorphous sucrose films as a function of temperature was successfully characterized. The peak energy, bandwidth and lifetime data suggest that it is sensitive to molecular mobility and can be used monitor molecular mobility in amorphous sucrose films. Time-resolved phosphorescence intensity decays from vanillin were multiexponential both below and above the glass transition temperature, indicating that the pure (single component) amorphous matrix was dynamically heterogeneous on the molecular level.
Vanillin analogs (hydroxy, dihydroxy and ethyl vanillin)) phosphorescence lifetime were found to be extremely sensitive to the local environment in the amorphous sucrose in the glassy state and at the glass-to-rubber transition into the melt, and provided useful insight about the mechanism of vanillin sensitivity to molecular mobility. Based on this the capability of movement of methoxyl group about the C-O bond is thought to be the contributor to sensitivity of vanillin to matrix molecular mobility. The other possibility is that the effect is not that of larger group but rather that of group (like methoxy and ethoxy) not able to hydrogen bond to matrix, which can have a coupling the probe vibrations to the matrix.
Vanillin phosphorescence demonstrated that the average rate of matrix molecular mobility rates increases with an increase in the molecular size and Tg of the sugar in the glucose homologous series. A comparative study of mobility in three excipients sucrose, trehalose and PVP, using vanillin phosphorescence provided useful insight about their stabilizing effect.
The phosphorescence from probes erythrosin B, vanillin and tryptophan was successfully utilized to measure molecular mobility on three different time scales corresponding to each probe in amorphous sucrose and protein film. Molecular mobility was successfully studied in amorphous sucrose films by monitoring phosphorescence from the dual probe combination of erythrosin B: vanillin, erythrosin B: tryptophan and vanillin:tryptophan.Ph.D.Includes bibliographical referencesby Rashmi Satyanarayan Tiwar
FIGURE 1 in Elotespora mumbaiensis sp. nov.: A novel species of Anamorphic Ascomycota reported from Peninsular India
No full textFIGURE 1. Elotespora mumbaiensis sp. nov.: A–C. Chain of conidia attached to host surface, D–F. Part of conidiomatal cup attached at the basal end of conidia chain (arrowed), G conidia chain initials attached on the lateral sides of conidia, H. Blackish brown apical and basal end of conidia, I. Broad and straight basal conidia, J. Scanning Electron Microscopic images showing chain of conidia (arrowed), K. Scanning Electron Microscopic images of conidiomatal cup (arrowed), L. Host stem infested with fungal colonies (arrowed), (Scale bar A–G & I = 20 μm, H=10 μm, J–K= 10 μm)Published as part of Dubey, Rashmi, 2021, Elotespora mumbaiensis sp. nov.: A novel species of Anamorphic Ascomycota reported from Peninsular India, pp. 177-180 in Phytotaxa 529 (1) on page 178, DOI: 10.11646/phytotaxa.529.1.15, http://zenodo.org/record/581424
Estrogen-mediated modulation of uropathogenic Dr+ Escherichia coli-induced uropathogenesis
No full textUrinary tract infection (UTI) is a disease of medical significance. One of the important clinical effects of estrogen deficiency in postmenopausal women is their increased susceptibility to UTIs. Estrogen replacement in these women is effective in prevention of bacteriuria. However, the molecular mechanisms involved with estrogen treatment against UTIs are poorly understood. Uropathogenic Dr+ E. coli can cause cystitis, recurrent UTI and pyelonephritis in humans, and induce chronic pyelonephritis in C3H/HeJ mice. Dr+ E. coli colonize and invade the host uroepithelium by adhering to decay accelerating factor (DAF) and type IV collagen and these are known to be hormonally regulated. In the present study, we investigated the role of estrogen and estrogen receptors (ER) in modulation of Dr+ E. coli uropathogenesis using an in vivo C3H/HeJ murine model and an in vitro model of mouse kidney inner medullary collecting duct (mIMCD3) cells. Ovariectomy (OVX) induced menopausal mice showed increased bacterial colonization in the bladder and kidney tissues compared to the ovary intact mice after experimental induction of Dr+ E. coli infection. Pretreatment of the OVX mice with beta-estradiol (E2) at a physiological dose reduced bacterial colonization. ER antagonist ICI 182,780 pretreatment increased bacterial colonization in the ovary intact mice, suggesting ER involvement. Furthermore, UTI induction in ERalpha-/- mice led to increased bacterial colonization in the bladder and kidney tissues compared to the ERalpha+/+ mice confirming ERalpha involvement. Increased kidney infection corresponded with an increase in DAF and type IV collagen expression in OVX as well as ERalpha-/- mice. Delayed induction of TLR2 and pro-inflammatory cytokines in the OVX and ERalpha-/- mice at onset of infection resulted in increased bacterial colonization compared to the control mice. Protective effects of estrogen against Dr+ E. coli invasion were also seen in mIMCD3 cells, where physiological levels of E2 led to a 40-50% reduction in bacteria
Sleep Deprivation Impairs Productivity in Adults With Mood Disorders: A Scoping Review
No full textAbstract
Date Presented 4/1/2017
Sleep deprivation (SD) is common in adults with mood disorders. Yet, little is known about how SD in adults with mood disorders may further restrict participation in occupations. This scoping review synthesized the literature on the effects of sleep deprivation on the productivity of adults with mood disorders.
Primary Author and Speaker: Melissa Knott
Contributing Authors: Christopher Derak, Lisa McAughey, Rashmi Mehrotra, Florence Roudbarani</jats:p
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