167 research outputs found
Recenzja pracy grupowej: N. Hauder, J. Jadach, P. Jankowska, M. Jeż, M. Jonczyk, p.t. "Zarządanie wartością przedsiębiorstwa na przykładzie organizacji X, Y, Z"
No full text<p>Recenzja pracy grupowej: N. Hauder, J. Jadach, P. Jankowska, M. Jeż, M. Jonczyk p.t. "Zarządzanie wartością przedsiębiorstwa na przykładzie organizacji X, Y, Z"</p
Defective interaction between Pol2p and Dpb2p, subunits of DNA polymerase epsilon, contributes to a mutator phenotype in Saccharomyces cerevisiae.
No full textMost of the prokaryotic and eukaryotic replicative polymerases are multi-subunit complexes. There are several examples indicating that noncatalytic subunits of DNA polymerases may function as fidelity factors during replication process. In this work, we have further investigated the role of Dpb2p, a noncatalytic subunit of DNA polymerase epsilon holoenzyme from Saccharomyces cerevisiae in controlling the level of spontaneous mutagenesis. The data presented indicate that impaired interaction between catalytic Pol2p subunit and Dpb2p is responsible for the observed mutator phenotype in S. cerevisiae strains carrying different mutated alleles of the DPB2 gene. We observed a significant correlation between the decreased level of interaction between different mutated forms of Dpb2p towards a wild-type form of Pol2p and the strength of mutator phenotype that they confer. We propose that structural integrity of the Pol epsilon holoenzyme is essential for genetic stability in S. cerevisiae cells
Proofreading deficiency of Pol I increases the levels of spontaneous rpoB mutations in E. coli
No full textThe fidelity role of DNA polymerase I in chromosomal DNA replication in E. coli was investigated using the rpoB forward target. These experiments indicated that in a strain carrying a proofreading-exonuclease-defective form of Pol I (polAexo mutant) the frequency of rpoB mutations increased by about 2-fold, consistent with a model that the fidelity of DNA polymerase I is important in controlling the overall fidelity of chromosomal DNA replication. DNA sequencing of rpoB mutants revealed that the Pol I exonuclease deficiency lead to an increase in a variety of base-substitution mutations. A polAexo mutator effect was also observed in strains defective in DNA mismatch repair and carrying the dnaE915 antimutator allele. Overall, the data are consistent with a proposed role of Pol I in the faithful completion of Okazaki fragment gaps at the replication fork
dnaX36 mutator of Escherichia coli: effects of the tau subunit of the DNA polymerase III holoenzyme on chromosomal DNA replication fidelity.
No full textThe Escherichia coli dnaX36 mutant displays a mutator effect, reflecting a fidelity function of the dnaX-encoded τ subunit of the DNA polymerase III (Pol III) holoenzyme. We have shown that this fidelity function (i) applies to both leading- and lagging-strand synthesis, (ii) is independent of Pol IV, and (iii) is limited by Pol II
Realizing Smart City Infrastructure at Scale, in the Wild: A Case Study
No full textCopyright \ua9 2022 James, Jonczyk, Smith, Harris, Komar, Bell and Ranjan.The smart city term has been widely used for a number of years and many pilot projects and limited scale, sector independent initiatives have been progressed, but comprehensive, long-term, city wide, multi-sector systems are much less evident. This paper examines one such case study in Newcastle, UK highlighting the challenges and opportunities that realizing “smart city” concepts at scale present. The paper provides the background to the Newcastle Urban Observatory project and discusses the socio-technical and practical challenges of developing and maintaining smart city networks of sensors in the plurality that is a modern city. We discuss the organizational requirements, governance, data quality and volume issues, big data management and discuss the current and future needs of decision makers and other city stakeholders. Finally, we propose areas where smart cities can have a positive impact on public outcomes through the discussion of two case studies related to COVID-19 and pedestrianization initiatives
The development of social capital: On managing game-players, trade-off makers and low-keys
No full textThis paper looks at how service professionals in the audit and consulting industry manage their social capital, i.e. their networks at a critical career stage: When they become project managers. We identify three prototypes of networkers, the game-players, the trade-off makers and the low-keys. The paper characterizes each prototype and confirms the descriptive validity by demonstrating how these prototypes are correlated to other network variables.
Writing a chapter on networking and dedicating it to this anniversary volume for Gilbert seems like a perfect match. When you have read the below chapter you will most certainly come to the conclusion that Gilbert Probst is part of the rare species of Master Networkers who never hesitated to make his rich social capital available to his doctoral students
From Internet of Things to Internet of Caring Things: A Paradigm Shift for Healthy Longevity
No full text\ua9 The Author(s) 2025. The global ageing population presents unique challenges and opportunities for technological innovation. This paper introduces the Internet of Caring Things (IoCT) as a novel evolution of the Internet of Things (IoT), reframing the approach to technology development for healthy ageing and longevity. Unlike traditional IoT applications or age-specific technologies, IoCT focuses on what people genuinely care about in their daily lives, integrating data-driven insights to support well-being across the lifespan. Through analysis of behavioral factors, market trends, and real-world case studies, this paper demonstrates how IoCT represents a significant paradigm shift in addressing healthy longevity challenges, moving from “caring about people” to “what people care about”
ChemInform Abstract: Reactions of Organic Anions. Part 184. A Simple Synthesis of gem‐ Bromochlorocyclopropanes via Phase‐Transfer Catalysis.
No full textExperimental studies on k-space strategies for MRI guided punctures in open high-field MRI at 1.0 T
No full textDurch neue Techniken ist eine nahezu Echtzeitbildgebung im MRT für
Interventionen möglich. Die fehlende Exposition mit ionisierenden Strahlen,
die multiplanare Schichtorientierung und der hohe Weichteilkontrast sowie die
Erfassung von funktionellen Daten prädestiniert die MRT für minimal-invasive
Eingriffe. Jedoch existiert derzeit kein Standard für minimale
Bildwiederholungsraten. Um maximale Sicherheit und Effizienz zu
gewährleisten, soll dies untersucht werden. Durch das konventionelle Keyhole
Imaging lassen sich MRT-Sequenzen beschleunigen. Daher wurde untersucht,
welchen Einfluss die reduzierte k-Raumfüllung auf die Darstellung eines
Nadelartefaktes hat und wie groß die Abweichung zwischen Bild und
tatsächlicher Nadelposition ist. Die Technik soll auf ihre Anwendbarkeit für
interventionelle MRT bewertet werden. In den Studien wurde das 1,0T Panorama
HFO MRT (Philips, Best, Netherlands) verwendet. Zwei Probandengruppen (A:
Erfahrene Untersucher (N=7); B: unerfahrene Probanden (N=13)) punktierten ein
statisches Gel-Phantommodell für die Punktionsstudie. Ausgewertet wurden die
Bildparameter SNR und CNR sowie die Punktionsparameter Zeit bis zum Auffinden
der Ebene (tl), Punktionsdauer (tp), getätigte Korrekturen (cn) und die
Distanz zur anvisierten Zielstruktur (dist) nach Beendigung des
Punktionsprocederes in Abhängigkeit zur Akquisitionszeit (ta) und der
Gruppenzugehörigkeit. Eine interaktive Sequenz wurde auf eine
Akquisitionszeit von ta=1s optimiert. Dann wurde sie verzögert, um
gleichbleibende Bildqualität bei unterschiedlichen Akquisitionszeiten ta=1s -
6s zu gewährleisten. Ein MR-kompatibler Punktionsautomat lieferte in der
k-Raumstudie iterative Bewegungen, die anhand von Gleichungen nachvollzogen
werden konnten. Die k-Raumfüllung einer Gradientenechosequenz wurde von 100%
(1,4s) in 10%-Schritten bis auf 20% reduziert und zusätzlich eine untere
Füllungsgrenze 15% (0,56s) angenommen. Die Qualität der Aufnahmen wurde
anhand der Parameter Kontrast (C), CNR, SNR sowie mit Hilfe der
Modulationstransferfaktoren (MTF) bestimmt und miteinander verglichen.
Weiterhin wurde der Beitrag der Bewegungen entlang (vl) und senkrecht zur
Nadel (vp) in Hinblick auf die Darstellung der Nadel ausgewertet. In der
Punktionsstudie zeigte sich, dass ein signifikanter Zusammenhang zwischen dem
Auffinden der Ebene sowohl für die Akquisitionszeit (p<0,001) als auch der
Gruppenzugehörigkeit (p=0,01) besteht (A: ta=1s 25±12s; ta=6s 55±21s; B:
ta=1s 22±13s; ta=6s 37±12s). Weiterhin konnte eine Verbindung (p<0,001)
zwischen der Akquisitionszeit und der Punktionsdauer dokumentiert werden (A:
ta=1s 59±36s; ta=6s 122±21s; B: ta=1s 47±23s; ta=6s 83±12s). Ein signifikanter
Zusammenhang besteht ab ta=4s. Ebenso korrelieren die Korrekturen (cn) mit der
Akquisitionszeit (p=0,04) und der Gruppenzugehörigkeit (p=0,01) (A: ta=1s
3±2; ta=6s 5±4; B: ta=1s 1,5±1,5s; ta=6s 2±2). Des Weiteren lag die
durchschnittliche Genauigkeit bei 5,6±3mm, während die Parameter SNR und CNR
konstant gehalten werden konnten. In der k-Raumstudie konnte kein
signifikanter Zusammenhang zwischen der Artefaktbreite und der k-Raumfüllung
festgestellt werden. Ebenfalls traten keine neuen Artefakte auf. Die
Abweichung der berechneten Nadelposition zu der Position des Artefaktes betrug
entlang der Nadel 3mm und senkrecht 0,8mm. Weiterhin ließ sich eine schwache
Korrelation (r=-0,14) zwischen der reduzierten k-Raumakquisition und dem CNR
festhalten. Es konnte gezeigt werden, dass Akquisitionszeiten bis zu 4s für
Interventionen an statischen Organen tolerabel sind. Allerdings ist es durch
das konventionelle Keyhole Imaging mit k-Raumfüllungen größer 15% möglich,
die zeitliche Auflösung bei Punktionen von Strukturen größer als 1mm auf
Bruchteile einer Sekunde ohne signifikanten Qualitätsverlust zu erhöhen,
wodurch der gesamte Interventionsprozess besser dokumentiert werden kann.Near real time MR-guided interventions are achievable using new techniques.
The lack of exposure to ionizing radiation, multiplanar slice orientation and
high soft tissue contrast as well as the acquisition of functional data
predestine MRI for minimally invasive interventions. However, there is
currently no standard for minimum frame rates. This has to be investigated to
ensure maximum safety and efficiency. MRI sequences can be accelerated by
using conventional keyhole imaging. Therefore, the influence of reduced
k-space filling on the presentation of a needle artefact and the difference
between image and physical needle position was investigated. The technique
will be evaluated for their applicability to interventional MRI. The 1.0T
Panorama HFO MRI (Philips, Best, The Netherlands) was used in the studies. Two
groups of experimentees (A: experienced investigators (N = 7), B:
inexperienced subjects (N = 13)) punctured a static gel phantom for the
puncture study. We analyzed the image parameters SNR and CNR and the puncture
parameters time to locate the plane (tl), puncture time (tp), done corrections
(cn) and the distance to the intended target structure (dist) after completion
of the puncture procedures in respect to the acquisition time (ta) and
affiliation to the groups. An interactive sequence has been optimized for an
acquisition time of ta=1s. This sequence was delayed to ensure consistent
image quality at different acquisition times ta=1s-6s. A MR-compatible
puncture machine provided iterative movements in the k-space study, which
could be reconstructed on the basis of equations. The k-space filling of a
gradient echo sequence of 100% (1.4 s) was reduced in 10% increments down to
20% and in addition a minimum filling of 15% (0.56 s) was assumed. Image
quality was measured and compared using the parameters contrast (C), CNR, SNR,
as well as the modulation transfer factors (MTF). Furthermore, the
contribution of movements along (vl) and perpendicular to the needle (vp) was
evaluated in regard to the representation of the needle in the images. The
puncture study showed a significant correlation of the time to locate the
plane to both, the acquisition time (p<0.001) and the affiliation to the
groups (p=0.01; A: ta=1s 25±12s; ta=6s 55±21s; B: ta=1s 22±13s; ta=6s 37±12s).
There is also a correlation (p<0.001) between the acquisition time and the
puncture time (A: ta=1s 59±36s; ta=6s 122±21s, B: ta=1s 47±23s; ta=6s 83±12s).
Moreover, the corrections (cn) correlates with the acquisition time (p=0.04)
and the affiliation to the groups (p=0.01; A: ta=1s 3±2; ta=6s 5±4; B: ta=1s
1.5±1.5 s; ta=6s 2±2). Furthermore, the average accuracy was measured with
5.6±3mm, keeping the parameters SNR and CNR constant. The k-space study could
not dedect a significant relationship between the width of the needle and the
k-space filling. Nevertheless, there were no new artefacts. The deviations of
the calculated needle tip positions to the position of the artefact were 3mm
along and 0.8mm vertically to the needle axes. Furthermore, a weak correlation
(r=-0.14) was found between the reduced k-space acquisition and the CNR. It
could be shown that acquisition times up to 4s for interventions to static
organs are acceptable. However, it is possible to increase temporal resolution
to fractions of a second for punctures on structures larger than 1mm without
significant loss in quality using conventional keyhole imaging with filiings
greater than 15%, so that the entire intervention process can be better
documented
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