123 research outputs found
Uncertainties inherent in the decomposition of a Transformation
This contribution adds to the points on the <indeterminacy of special
relativity> made by De Abreu and Guerra. We show that the Lorentz
Transformation can be composed by the physical observations made in a frame K
of events in a frame K-prime viz i) objects in K-prime are moving at a speed v
relative to K, ii) distances and time intervals measured by K-prime are at
variance with those measured by K and iii) the concept of simultaneity is
different in K-prime compared to K. The order in which the composition is
executed determines the nature of the middle aspect (ii). This essential
uncertainty of the theory can be resolved only by a universal synchronicity as
discussed in [1] based on the unique frame in which the one way speed of light
is constant in all directions.Comment: 10 pages including an appendix. Published in the European Journal of
Physics as a Comment. Eur. J. Phys. 29 (2008) L13-L1
Simple and Rapid Methods for the Analysis of Captopril in Dosage Forms
Abstract: Two indirect methods are described for the micro determination of captopril using hexacyanoferrate (III) as reagent. The reaction used for titrimetry proceeds at room temperature and will be complete in 10 minute with a stoichiometry of 1:1 with respect to the oxidant and captopril. The reaction product used for spectrophotometric determination shows the absorption maximum at 510 nm. The Beer's law is obeyed over the concentration range 0.25-12.00 µg mL -1 , the molar absorptivity and Sandell sensitivity for the system being 9.14×10 3 L mol -1 cm -1 and 23.78 ng cm -2 , respectively. The limit of detection and quantification are found to be 0.08 and 0.26 µg mL -1 , respectively. Both procedures have been applied to the determination of captopril in tablets. The results have been statistically compared with those obtained by the official (BP) method
Simple and Rapid Methods for the Analysis of Captopril in Dosage Forms
Two indirect methods are described for the micro determination of captopril using hexacyanoferrate (III) as reagent. The reaction used for titrimetry proceeds at room temperature and will be complete in 10 minute with a stoichiometry of 1:1 with respect to the oxidant and captopril. The reaction product used for spectrophotometric determination shows the absorption maximum at 510 nm. The Beer’s law is obeyed over the concentration range 0.25-12.00 μg mL-1, the molar absorptivity and Sandell sensitivity for the system being 9.14×103 L mol-1cm-1 and 23.78 ng cm-2, respectively. The limit of detection and quantification are found to be 0.08 and 0.26 μg mL-1, respectively. Both procedures have been applied to the determination of captopril in tablets. The results have been statistically compared with those obtained by the official (BP) method
Reversal in time order of interactive events: Collision of inclined rods
In the rod and hole paradox as described by Rindler (1961 Am. J. Phys. 29
365-6), a rigid rod moves at high speed over a table towards a hole of the same
size. Observations from the inertial frames of the rod and slot are widely
different. Rindler explains these differences by the concept of differing
perceptions in rigidity. Gron and Johannesen (1993 Eur. J. Phys. 14 97-100)
confirmed this aspect by computer simulation where the shapes of the rods are
different as observed from the co-moving frames of the rod and slot. Lintel and
Gruber (2005 Eur. J. Phys. 26 19-23) presented an approach based on retardation
due to speed of stress propagation. In this paper we consider the situation
when two parallel rods collide while approaching each other along a line at an
inclination with their axis. The collisions of the top and bottom ends are
reversed in time order as observed from the two co-moving frames. This result
is explained by the concept of extended present derived from the principle of
relativity of simultaneity
Reducing Operating Room Costs through Real Time Cost Information Feedback: A Pilot Study
Purpose: To create a protocol for providing real-time operating room (OR) cost feedback to surgeons. We hypothesize that this protocol will reduce costs in a responsible way without sacrificing quality of care.
Methods: All OR costs were obtained and recorded for robot-assisted partial nephrectomy and laparoscopic donor nephrectomy. Before the beginning of this project, costs pertaining to the 20 most recent cases were analyzed. Items were identified from previous cases as modifiable for replacement or omission. Timely feedback of total OR costs and cost of each item used was provided to the surgeon after each case, and costs were analyzed.
Results: A cost analysis of the robot-assisted partial nephrectomy before the washout period indicates expenditures of 1229.33 representing 23.4% of the total cost. A postwashout period cost analysis found the total OR cost decreased by 3530.05 with 289.73 (8.0%). No complications occurred in the donor nephrectomy cases while one postoperative complication occurred in the partial nephrectomy group.
Conclusion: Providing surgeons with feedback related to OR costs may lead to a change in surgeon behavior and decreased overall costs. Further studies are needed to show equivalence in patient outcomes
The Post-COVID-19 Era: Interdisciplinary Demands of Contagion Surveillance Mass Spectrometry for Future Pandemics
Mass spectrometry (MS) can become a potentially useful instrument type for aerosol, droplet and fomite (ADF) contagion surveillance in pandemic outbreaks, such as the ongoing SARS-CoV-2 pandemic. However, this will require development of detection protocols and purposing of instrumentation for in situ environmental contagion surveillance. These approaches include: (1) enhancing biomarker detection by pattern recognition and machine learning; (2) the need for investigating viral degradation induced by environmental factors; (3) representing viral molecular data with multidimensional data transforms, such as van Krevelen diagrams, that can be repurposed to detect viable viruses in environmental samples; and (4) absorbing engineering attributes for developing contagion surveillance MS from those used for astrobiology and chemical, biological, radiological, nuclear (CBRN) monitoring applications. Widespread deployment of such an MS-based contagion surveillance could help identify hot zones, create containment perimeters around them and assist in preventing the endemic-to-pandemic progression of contagious diseases
Shortest Path Problems on a Polyhedral Surface
We develop algorithms to compute shortest path edge sequences, Voronoi diagrams, the Fréchet distance, and the diameter for a polyhedral surface
Design agency:prototyping multi-agent systems in architecture
This paper presents research on the prototyping of multi-agent systems for architectural design. It proposes a design exploration methodology at the intersection of architecture, engineering, and computer science. The motivation of the work includes exploring bottom up generative methods coupled with optimizing performance criteria including for geometric complexity and objective functions for environmental, structural and fabrication parameters. The paper presents the development of a research framework and initial experiments to provide design solutions, which simultaneously satisfy complexly coupled and often contradicting objectives. The prototypical experiments and initial algorithms are described through a set of different design cases and agents within this framework; for the generation of façade panels for light control; for emergent design of shell structures; for actual construction of reciprocal frames; and for robotic fabrication. Initial results include multi-agent derived efficiencies for environmental and fabrication criteria and discussion of future steps for inclusion of human and structural factors
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KAT2A complexes ATAC and SAGA play unique roles in cell maintenance and identity in hematopoiesis and leukemia
Author notes:
*E.F. and S.W. contributed equally to this study.
ChIP-seq and A-seq data have been deposited in GEO (accession numbers GSE128902 and GSE128512).
Send data sharing requests via e-mail to the corresponding author.
The full-text version of this article contains a data supplement.Copyright © 2021 The Authors. Epigenetic histone modifiers are key regulators of cell fate decisions in normal and malignant hematopoiesis. Their enzymatic activities are of particular significance as putative therapeutic targets in leukemia. In contrast, less is known about the contextual role in which those enzymatic activities are exercised, and specifically, how different macromolecular complexes configure the same enzymatic activity with distinct molecular and cellular consequences. We focus on KAT2A, a lysine acetyltransferase responsible for Histone 3 Lysine 9 acetylation, which we recently identified as a dependence in Acute Myeloid Leukemia stem cells, and that participates in 2 distinct macromolecular complexes: Ada Two- A-Containing (ATAC) and Spt-Ada-Gcn5-Acetyltransferase (SAGA). Through analysis of human cord blood hematopoietic stem cells and progenitors, and of myeloid leukemia cells, we identify unique respective contributions of the ATAC complex to regulation of biosynthetic activity in undifferentiated self-renewing cells, and of the SAGA complex to stabilisation or correct progression of cell type-specific programs with putative preservation of cell identity. Cell type and stage-specific dependencies on ATAC and SAGA-regulated programs explain multi-level KAT2A requirements in leukemia and in erythroid lineage specification and development. Importantly, they set a paradigm against which lineage specification and identity can be explored across developmental stem cell systems.Rosetrees Trust PhD Studentship; Kendall Leukaemia Fund Intermediate Fellowship (KKL888); Leuka John Goldman Fellowship for Future Science (2017); Wellcome Trust/University of Cambridge ISSF Grant; Lady Tata Memorial Trust PhD Studentship; Trinity Henry Barlow Trust Studentship; NIH RO1 grant (1R01GM131626-01); Agence Nationale de la Recherche (ANR) Program grants (AAPG2019 PICen, PRCI AAPG2019 EpiCAST, ANR-10-LABX-0030-INRT, frame program Investissements d’Avenir ANR-10IDEX-0002-02); Brunel University
A Strategy for Origins of Life Research
Aworkshop was held August 26–28, 2015, by the Earth-
Life Science Institute (ELSI) Origins Network (EON,
see Appendix I) at the Tokyo Institute of Technology. This
meeting gathered a diverse group of around 40 scholars researching
the origins of life (OoL) from various perspectives
with the intent to find common ground, identify key questions
and investigations for progress, and guide EON by suggesting
a roadmap of activities.
Specific challenges that the attendees were encouraged to
address included the following: What key questions, ideas,
and investigations should the OoL research community address
in the near and long term? How can this community
better organize itself and prioritize its efforts? What roles
can particular subfields play, and what can ELSI and EON
do to facilitate research progress? (See also Appendix II.)
The present document is a product of that workshop; a
white paper that serves as a record of the discussion that
took place and a guide and stimulus to the solution of the
most urgent and important issues in the study of the OoL.
This paper is not intended to be comprehensive or a balanced
representation of the opinions of the entire OoL research
community. It is intended to present a number of
important position statements that contain many aspirational
goals and suggestions as to how progress can be made in
understanding the OoL.
The key role played in the field by current societies and
recurring meetings over the past many decades is fully acknowledged,
including the International Society for the
Study of the Origin of Life (ISSOL) and its official journal
Origins of Life and Evolution of Biospheres, as well as the
International Society for Artificial Life (ISAL)
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