1,859 research outputs found
ATM and ATR signaling at a glance
Get PDFATM and ATR signaling pathways are well conserved throughout evolution and are central to the maintenance of genome integrity. Although the role of both ATM and ATR in DNA repair, cell cycle regulation and apoptosis have been well studied, both still remain in the focus of current research activities owing to their role in cancer. Recent advances in the field suggest that these proteins have an additional function in maintaining cellular homeostasis under both stressed and non-stressed conditions. In this Cell Science at a Glance article and the accompanying poster, we present an overview of recent advances in ATR and ATM research with emphasis on that into the modes of ATM and ATR activation, the different signaling pathways they participate in - including those that do not involve DNA damage - and highlight their relevance in cancer
An interactive human-machine control interface for an autonomous shuttle
No full textAutonomous Shuttles are touted to be the first widespread implementation of autonomous vehicles for the first and last-mile applications in urban mobility. Extensive research in the field of autonomous mobility is being carried out in various aspects which include sensor data fusion, planning, perception, localization, mapping, and control algorithms. These algorithms need real-world data for testing, development, and validation. This paper proposes a modular architecture for easy integration of diverse autonomous driving logics in an autonomous driving system. Further, the proposed architecture is applied on an autonomous shuttle to develop a human-machine interface for facilitating the research in Politecnico di Milano
Heterodermia flabellata Awasthi
No full text<i>Heterodermia flabellata</i> (Fée) Awasthi <p> NEW REPORT. — Chapada do Céu, Parque Nacional das Emas, on bark, leg. <i>A. Aptroot 85583</i>. New to Goiás.</p>Published as part of <i>R, Jeanne dos, Silva, eis, Aptroot, André, E, Marcela, S, ugenia da & Cáceres, ilva, 2023, Lichens from dry central Brazil: a checklist of lichenized fungi from Distríto Federal and Goiás, pp. 117-133 in Cryptogamie, Mycologie 20 (9)</i> on page 127, DOI: 10.5252/cryptogamie-mycologie2023v44a9, <a href="http://zenodo.org/record/8434271">http://zenodo.org/record/8434271</a>
Robust Communication-Optimal Distributed Clustering Algorithms
Get PDFIn this work, we study the k-median and k-means clustering problems when the data is distributed across many servers and can contain outliers. While there has been a lot of work on these problems for worst-case instances, we focus on gaining a finer understanding through the lens of beyond worst-case analysis. Our main motivation is the following: for many applications such as clustering proteins by function or clustering communities in a social network, there is some unknown target clustering, and the hope is that running a k-median or k-means algorithm will produce clusterings which are close to matching the target clustering. Worst-case results can guarantee constant factor approximations to the optimal k-median or k-means objective value, but not closeness to the target clustering.
Our first result is a distributed algorithm which returns a near-optimal clustering assuming a natural notion of stability, namely, approximation stability [Awasthi and Balcan, 2014], even when a constant fraction of the data are outliers. The communication complexity is O~(sk+z) where s is the number of machines, k is the number of clusters, and z is the number of outliers. Next, we show this amount of communication cannot be improved even in the setting when the input satisfies various non-worst-case assumptions. We give a matching Omega(sk+z) lower bound on the communication required both for approximating the optimal k-means or k-median cost up to any constant, and for returning a clustering that is close to the target clustering in Hamming distance. These lower bounds hold even when the data satisfies approximation stability or other common notions of stability, and the cluster sizes are balanced. Therefore, Omega(sk+z) is a communication bottleneck, even for real-world instances
Shoreoxylon deomaliense Prakash & Awasthi
No full textShoreoxylon cf. deomaliense Prakash & Awasthi (Fig. 15) Shoreoxylon deomaliense Prakash & Awasthi, 1971: 219, pl. 1, figs 3-4. HOLOTYPE. — Birbal Sahni Institute of Palaeosciences Museum, India, specimen no. 34050. MATERIAL. — MNHN.F.50192 (field number: NAT17-4). Estimated minimal diameter: 25-37 cm. LOCALITY. — Kalewa Township, Sagaing Region, Myanmar. AGE. — Upper lower to lowermost middle Miocene. DESCRIPTION Wood diffuse-porous, showing lateral compression. Growth limits marked by tangential canal lines. Vessels about 77-90% solitary (Fig. 15A) and in radial groups of 2-4, oval due to lateral compression, 4-13 per mm² (average: 8; likely overestimated due to compression); tangential diameter 120-200 µm (average: 150 µm; likely underestimated due to compression). Tyloses present (Fig. 15F). Vessel elements 140-460 µm (average: 330 µm) long. Perforation plates simple. Intervessel pits alternate. Vessel-ray pits not preserved. Vasicentric tracheids present (Fig. 15F). Parenchyma mostly vasicentric and aliform with short wings, sometimes confluent (Fig. 15B) or rarely forming thin bands from several rays to rays; diffuse parenchyma with cells larger than fibres ones (Fig. 15K), sometimes gathered in small groups; thin bands of parenchyma are tangentially crossing the section at regular intervals (5-7 mm). They can contain secretory canals but these ones are not always visible (Fig. 15H). When no canal is present, the bands are only 1-4 cells wide. Parenchyma cells 50-90 µm long (average: 70 µm), 15-35 µm wide (average: 25 µm) in tangential section; sometimes crystals in chambered cells (up to 8 crystals per strand seen) (Fig. 15E). Parenchyma cells can be more or less enlarged in the form of idioblasts. Rays 1- to 5-(6-)seriate (mainly 4) (Fig. 15C), uniseriate about 15% of the rays, non-storied, 5-10 rays per mm (average: 8), 270-1600 µm (average: 650 µm) or up to 30-40 (even 70) cells high, heterocellular made of procumbent cells with 1-4 or more upright cells at the ends (Fig. 15G), end-to-end fusion possible resulting in very high rays (Fig. 15D). Fibres non-septate, 5-19 µm (average: 12 µm) wide, thin-to-thick walled (lumina 1 time the double wall thickness in average) (Fig. 15J). Secretory canals in long tangential lines surrounded by parenchyma (Fig. 15A, H, I), but also in seemingly short lines probably due to compression in concentric parenchyma bands, or very rarely scattered by 2 in the section, 30-100 µm in tangential diameter (average 60 µm). DISCUSSION This specimen is characterized by: 1) diffuse-porous wood; 2) mostly solitary vessels as well as in radial groups; 3) crystalliferous and mostly aliform parenchyma, as well as diffuse; 4) 1-6-seriate heterocellular rays; 5) long tangential lines of secretory canals; and 6) vasicentric tracheids. As for our previous specimens (start p. 878), these features are diagnostic of the Dipterocarpaceae family. According to the identification key of Schweitzer (1958), long tangential lines of canals are found in the genera Shorea, Dryobalanops, Hopea, and Parashorea Kurz but the latter three can be dismissed: the genus Dryobalanops has exclusively solitary vessels and visible fibretracheids, Hopea has smaller and more frequent vessels (less than 200 µm in average diameter for 10-20 or more vessels per mm²), while Parashorea has less vessels and larger rays (up to 7-seriate) (Metcalfe & Chalk 1950; Gottwald & Parameswaran 1966; Soerianegara & Lemmens 1993; Richter & Dallwitz 2000 -onward; Ogata et al. 2008). The genus Shorea is divided into several sections that are more or less phylogenetically supported and roughly characterized by few features: section ‘Pentacme’ by big vessels, section ‘Richetioides’ (or ‘Richetia’) by the presence of radial canals, section ‘Anthoshorea’ by the presence of silica bodies in ray cells as well as short rays, thin-walled fibres and rare crystals in parenchyma, sections ‘Rubroshorea’ by solitary crystals or in short chain of non-chambered (or chambered) parenchyma cells and idioblasts, section ‘Shorea’ by short rays, few marginal ray cells and crystals in long chains of chambered parenchyma cells and idioblasts. The present wood would thus be close to the section ‘ Shorea ”. Among Shorea extant species, Shorea laevis Ridl. shares many features of our fossil including the aliform parenchyma (but without crystals), the vessel size and density, the similar rays (mostly 3-5-seriate) with few marginal cells and few uniseriate rays. The same arrangement of crystalliferous parenchyma and ray size is found in S. parvifolia Dyer, S. pauciflora King, S. atrinervosa Symington., and with a lesser extent in S. maxwelliana King and S. almon Foxw. Shoreoxylon groups the fossil specimens close to all Shorea and Parashorea. The genus Hopenium was instituted (Awasthi 1980) for woods resembling Hopea, with upright ray cells in the middle of the rays. Species descriptions in Shoreoxylon are often overlapping and rarely consider inter- and intraspecific variations. In addition, they sometimes lack diagnostic characters or qualitative illustrations. Consequently, it is difficult to identify a unique species that could be attributed to our specimen. Some species display features that are close to our fossil (Appendix 1): Shoreoxylon burmense Prakash (Prakash 1965a, 1973; Licht et al. 2014) share the same type of rays, the parenchyma is also quite similar, but the secretory canals are grouped in very close lines, from 2 to 4, which is not the case in our fossil, and it has no crystal in parenchyma. Shoreoxylon indicum Awasthi (1974) has the same vessel and ray distribution, crystals in parenchyma cells, but its apotracheal and confluent parenchyma are more developed whith only 5 crystals per parenchyma strands (up to 8 in our fossil). Shoreoxylon posthumi Schweitzer (1958) has crystals in parenchyma as well as enlarged parenchyma cells, but it has much developed apotracheal parenchyma and its canal lines are irregularly distributed or superimposed. Shoreoxylon tipamense Prakash & Awasthi (1970) has similar vessel, parenchyma and ray arrangement, but it also has bigger vessels, larger canals, thinner fibres cell walls and sheath cells. Shoreoxylon deomaliense is the closest fossil species to our specimen (Prakash & Awasthi 1971; Licht et al. 2014), though the present fossil has a lesser frequency of vessels, more aliform parenchyma and slightly thinner rays (up to 6-seriate, compared to 7-seriate for S. deomaliense) with shorter rows of marginal ray cells. Considering its preservation, we attribute our fossil to Shoreoxylon cf. deomaliense. Shorea is a genus of tropical Asian trees growing in humid lowland areas, on podzols and peat swamps, mostly below 1000 m altitude (Ashton 1982; Soerianegara & Lemmens 1993). Shorea laevis mostly grows on well-drained to dry soils, on ridges or hillsides up to 1000 m. It is also found in lowland mixed dipterocarp forests and on alluvial sites (Ashton 1982; Soerianegara & Lemmens 1993; Pooma et al. 2017). All the other species cited above are found in mixed dipterocarp forests in lowlands or on rolling hills, on well-drained soils at up to 1000 m altitude (Ashton 1982, 2004).Published as part of Gentis, Nicolas, Licht, Alexis, Boura, Anaïs, Aung, Dario De Franceschi Zaw Win Day Wa & Dupont-Nivet, Guillaume, 2022, Fossil wood from the lower Miocene of Myanmar (Natma Formation): palaeoenvironmental and biogeographic implications, pp. 853-909 in Geodiversitas 44 (28) on pages 882-884, DOI: 10.5252/geodiversitas2022v44a28, http://zenodo.org/record/714530
Boerhaavia diffusa-Derived Antiviral Glycoprotein: A Novel, Eco-friendly Approach for the Management of Viral Diseases
No full textInternational audienceMany higher plants are known to contain endogenous proteins that act as virus inhibitors (Hansen 1989; Chessin et al. 1995 and Verma et al. 1998). All these belong to a class of proteins called ribosome-inactivating proteins (RIPs). These proteins have been studied in Phytolacca americana (Irvin 1975), Mirabilis jalapa (Kubo et al. 1990), and Trichosanthes kirilowii (Yeung et al. 1988) and show antiviral activity when mixed with virus inoculum (Loebenstein 1972; Kumar et al. 1997). On the other hand, some virus inhibitors of plant origin have been reported to induce systemic resistance in non-treated parts of plants also and thereby preventing infection of viruses (Verma et al. 1979; Ponz and Broening 1986; Verma et al. 1995, 1996, 1998). One such glycoproteinaceous substance isolated from B. diffusa roots has prevented virus infection and multiplication in plants (Verma and Awasthi 1979: Verma et al. 1979). It has shown very high antiviral activity when mixed with viruses in vitro and provoked the plant system to produce new protein(s) in the treated plants which is the actual virus inhibitory agent (VIA) (Verma and Awasthi 1980). This glycoprotein induces antiviral state in the plants, through formation of a de novo synthesized protein, and perhaps is active in signaling the activation of defense mechanism in susceptible hosts
Synthesis of ZnO nanostructures
No full textZinc oxide (ZnO) is an inorganic compound. It can be present in three crystal structures: wurtzite, zinc blende, and rock-salt. At ambient conditions, the wurtzite structure is the most stable phase thermodynamically, in which zinc atoms are coordinated with four oxygen atoms with the Zn atom at the center of the tetrahedron. ZnO has attracted intensive research efforts for versatile applications in nanoelectronics, optics, piezoelectric devices, energy conversion devices, chemical sensors, and photocatalysts. Because of these unique physicochemical properties and the requirement of energy-efficient and miniaturized devices, researchers have focused on the synthesis of ZnO nanostructures, which involves the manufacturing and applications of materials with the size under 100nm in one or more dimensions. The well-defined morphologies like quantum dots, nanowires, nanorods, nanocages, nanotetrapods, nanoflowers, and nanoforests have been successfully grown via a variety of strategies including thermal evaporation, electrodeposition, sputtering, electrospinning, and hydrothermal technique. In general, nanostructure production is a complicated process, and different process parameters have a great impact on the properties of the resulting product, however, the parameters in various synthesis methods lead to different shapes and sizes of the nanostructures. In this chapter, we are going to discuss the synthesis process of some of the nanostructures with different techniques.</p
Supplementary_Material – Supplemental material for Clinicopathological parameters influencing inhibitor development in patients with hemophilia A receiving on-demand therapy
No full textSupplemental material, Supplementary_Material for Clinicopathological parameters influencing inhibitor development in patients with hemophilia A receiving on-demand therapy by Sanya Arshad, Anshima Singh, Namrata Punit Awasthi, Swati Kumari and Nuzhat Husain in Therapeutic Advances in Hematology</p
The lichen genus Parmotrema A. Massal. (Lecanorales, Ascomycota) from India with addition distributional records
No full textA detailed morpho-taxonomic account of 53 species of lichen genus Parmotrma is provided.
Based on the phylogenetic studies carried out elsewhere now Parmelaria subthomsonii D.D.
Awasthi and P. thomsonii (Stirt.) D.D. Awasthi are transferred in the genus Parmotrema. Key to
the species of Parmotrema known from India and their additional distribution are also provided.</jats:p
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