cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Towards improving the accuracy of aortic transvalvular pressure gradients: rethinking Bernoulli
Creators: name: Franke, Benedikt
name: Weese, J.
name: Waechter-Stehle, I.
name: Brüning, Jan
name: Kuehne, Titus
name: Goubergrits, Leonid
Publisher: name: Charité - Universitätsmedizin Berlin
Year: 2020
Subjects: subject: Aortic valve stenosis
subject: Bernoulli equation
subject: Computational fluid dynamics
subject: Aortic valve area
subject: Transvalvular pressure gradient
subject: 600 Technik, Medizin, angewandte Wissenschaften::610 Medizin und Gesundheit::610 Medizin und Gesundheit

description: The transvalvular pressure gradient (TPG) is commonly estimated using the Bernoulli equation. However, the method is known to be inaccurate. Therefore, an adjusted Bernoulli model for accurate TPG assessment was developed and evaluated. Numerical simulations were used to calculate TPGCFD in patient-specific geometries of aortic stenosis as ground truth. Geometries, aortic valve areas (AVA), and flow rates were derived from computed tomography scans. Simulations were divided in a training data set (135 cases) and a test data set (36 cases). The training data was used to fit an adjusted Bernoulli model as a function of AVA and flow rate. The model-predicted TPGModel was evaluated using the test data set and also compared against the common Bernoulli equation (TPGB). TPGB and TPGModel both correlated well with TPGCFD (r > 0.94), but significantly overestimated it. The average difference between TPGModel and TPGCFD was much lower: 3.3 mmHg vs. 17.3 mmHg between TPGB and TPGCFD. Also, the standard error of estimate was lower for the adjusted model: SEEModel = 5.3 mmHg vs. SEEB = 22.3 mmHg. The adjusted model's performance was more accurate than that of the conventional Bernoulli equation. The model might help to improve non-invasive assessment of TPG. Graphical abstract Processing pipeline for the definition of an adjusted Bernoulli model for the assessment of transvalvular pressure gradient. Using CT image data, the patient specific geometry of the stenosed AVs were reconstructed. Using this segmentation, the AVA as well as the volume flow rate was calculated and used for model definition. This novel model was compared against classical approaches on a test data set, which was not used for the model definition.
title: An investigation into factor influencing the use of supermarket loyalty card data amongst small agri-food companies
Creators: name: Ihua, Ugwushi Bellema
Publisher: name: University of Kent
Year: 2022

description: The research on which this thesis is based sought to provide new insights into the use of supermarket loyalty card data (SLCD) amongst small agri-food companies; with respect to the factors influencing their use of formalised market information. Given the lack of research in this area and on the key constructs (barriers and enablers) upon which this thesis is focussed, a casestudy approach was adopted. Data was collected in two phases, and it comprised of thirteen in-depth semi-structured interviews for the 1 st phase and two in-depth case studies for the 2nd phase. The qualitative data generated was analysed using thematic analysis. The thesis investigated four interrelated groups of factors influencing the use of supermarket loyalty card data - organisational, individual-related, informational and relationship factors. The results revealed that, amongst the four groups of factors investigated, the individual-related factors seemed to exhibit more influence on the use of the data amongst the small food companies investigated. Components of this group include: education, economic history, administrative familiarity, information- seeking personality and decision-making rationality of the owner-managers; as well as their involvement of staff, desire for growth and networking ability. In summary, whilst the existing body of knowledge suggests that small businesses tend to rely more on informal sources of information, this thesis has provided some evidence to suggest that there are some small businesses making use of formalised market information, and in a structured manner, to enhance their marketing decisions. And those small businesses seemed to perform better than their counterparts who did not avail themselves of such forms of market information. Also, whilst the study provided some evidence of the existence of instrumental, conceptual and selective (as opposed to symbolic) use of SLCD amongst small businesses, it also unearthed the concept of "emblematic use" of market information. This refers to the positive image and credibility gained by some of the small agri- food companies on account of merely possessing supermarket loyalty card data. In this situation, market information is used merely as an emblem, and this dimension has not been previously investigated in the literature.
Note: Equation of state and the freezing point in the hard-sphere model
Creators: name: Robles, Miguel
name: de Haro, Mariano López
name: Santos, Andrés
Publisher: name: arXiv
Year: 2014
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: The merits of different analytical equations of state for the hard-sphere system with respect to the recently computed high-accuracy value of the freezing-point packing fraction are assessed. It is found that the Carnahan-Starling-Kolafa and the branch-point approximant equations of state yield the best performance.
description: 3 pages, 1 figure; v2: chemical potential added
Get Organized! A well-planned archival visit results in well-managed data
Creators: name: Budke, Leah
name: Noppe, Nele
Publisher: name: Zenodo
Year: 2022
Subjects: archives, research data management

description: How to plan for a fruitful archive visit and manage your research data every step of the way? This presentation introduces basic archive know-how, useful organization tools like Zotero and Tropy, and many tips and tricks for researchers heading into their first archival visit. Presented as part of the two-day workshop "From paper to files: how to efficiently digitize (historical) documents", which took place at KU Leuven on November 22-23, 2022. The workshop also introduced participants to other parts of a practical workflow for acquiring and processing physical archival materials, including photographing documents with cellphone cameras and performing optical character recognition (OCR) and handwritten text recognition (HTR) using tools like ABBYY Finereader and Transkribus.
HVDC-WISE Deliverable 1.1 Project Handbook
Creators: name: Gonzalez, Juan Carlos
name: Morel, Florent
Publisher: name: Zenodo
Year: 2022
Subjects: VDC-WISE
HVDC
AC/DC
handbook
project management
guidelines

description: The HVDC-WISE project handbook provides an overview of the project management structure and infrastructure adopted during the project or set out in the Consortium Agreement and Grant Agreement. This handbook also represents a set of guidelines for all HVDC-WISE members.
Multicharged optical vortices induced in a dissipative atomic vapor system
Creators: name: Zhang, Yiqi
name: Belic, Milivoj R.
name: Wu, Zhenkun
name: Yuan, Chenzhi
name: Wang, Ruimin
name: Lu, Keqing
name: Zhang, Yanpeng
Publisher: name: arXiv
Year: 2013
Subjects: subject: Optics (physics.optics)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: We investigate numerically the dynamics of optical vortex beams carrying different topological charges, launched in a dissipative three level ladder type nonlinear atomic vapor. We impose the electromagnetically induced transparency (EIT) condition on the medium. Linear, cubic, and quintic susceptibilities, considered simultaneously with the dressing effect, are included in the analysis. Generally, the beams slowly expand during propagation and new vortices are induced, commonly appearing in oppositely charged pairs. We demonstrate that not only the form and the topological charge of the incident beam, but also its growing size in the medium greatly affect the formation and evolution of vortices. We formulate common rules for finding the number of induced vortices and the corresponding rotation directions, stemming from the initial conditions of various incident beams, as well as from the dynamical aspects of their propagation. The net topological charge of the vortex is conserved during propagation, as it should be, but the total number of charges is not necessarily same as the initial number, because of the complex nature of the system. When the EIT condition is lifted, an enhancement region of beam dynamics if reached, in which the dynamics and the expansion of the beam greatly accelerate. In the end, we discuss the liquid like behavior of light evolution in this dissipative system and propose a potential experimental scheme for observing such a behavior.
description: 9 pages, 6 figures, 3 tables
Calix[4]pyrrolato gallate: square planar-coordinated gallium(iii) and its metal–ligand cooperative reactivity with CO2 and alcohols
Creators: name: Sigmund, Lukas M.
name: Engels, Eliane
name: Richert, Nick
name: Greb, Lutz
Publisher: name: Freie Universität Berlin
Year: 2022
Subjects: subject: calix[4]pyrrolato gallates
subject: synthesis
subject: characterization
subject: reactivity
subject: 500 Naturwissenschaften und Mathematik::540 Chemie::540 Chemie und zugeordnete Wissenschaften

description: Forcing a priori tetracoordinate atoms into planar configuration represents a promising concept for enhanced reactivity of p-block element-based systems. Herein, the synthesis, characterization, and reactivity of calix[4]pyrrolato gallates, constituting square planar-coordinated gallium(III) atoms, are reported. Unusual structural constraint-induced Lewis acidity against neutral and anionic donors is disclosed by experiment and rationalized by computations. An energetically balanced dearomatization/rearomatization of a pyrrole unit enables fully reversible metal–ligand cooperative capture of CO2. While alcohols are found unreactive against the gallates, a rapid and selective OH-bond activation can be triggered upon protonation of the ligand. Secondary ligand–sphere modification adds a new avenue to structurally-constrained complexes that unites functional group tolerance with unconventional reactivity.
Development and description of measurement properties of an instrument to assess treatment burden among patients with multiple chronic conditions
Creators: name: Ravaud, Philippe
name: Falissard, Bruno
name: Baruch, Dan
name: Tran, Viet-Thi
name: Montori, Victor M.
name: Eton, David T.
Publisher: name: Columbia University
Year: 2012
Subjects: Medical sciences

description: Patients experience an increasing treatment burden related to everything they do to take care of their health: visits to the doctor, medical tests, treatment management and lifestyle changes. This treatment burden could affect treatment adherence, quality of life and outcomes. We aimed to develop and validate an instrument for measuring treatment burden for patients with multiple chronic conditions. Items were derived from a literature review and qualitative semistructured interviews with patients. The instrument was then validated in a sample of patients with chronic conditions recruited in hospitals and general practitioner clinics in France. Factor analysis was used to examine the questionnaire structure. Construct validity was studied by the relationships between the instrument's global score, the Treatment Satisfaction Questionnaire for Medication (TSQM) scores and the complexity of treatment as assessed by patients and physicians. Agreement between patients and physicians was appraised. Reliability was determined by a test-retest method. A sample of 502 patients completed the Treatment Burden Questionnaire (TBQ), which consisted of 7 items (2 of which had 4 subitems) defined after 22 interviews with patients. The questionnaire showed a unidimensional structure. The Cronbach's α was 0.89. The instrument's global score was negatively correlated with TSQM scores (rs = -0.41 to -0.53) and positively correlated with the complexity of treatment (rs = 0.16 to 0.40). Agreement between patients and physicians (n = 396) was weak (intraclass correlation coefficient 0.38 (95% confidence interval 0.29 to 0.47)). Reliability of the retest (n = 211 patients) was 0.76 (0.67 to 0.83). This study provides the first valid and reliable instrument assessing the treatment burden for patients across any disease or treatment context. This instrument could help in the development of treatment strategies that are both efficient and acceptable for patients.
Heterogeneous metallaphotoredox catalysis in a continuous-flow packed-bed reactor
Creators: name: Hsu, Wei-Hsin
name: Reischauer, Susanne
name: Seeberger, Peter H.
name: Pieber, Bartholomäus
name: Cambié, Dario
Publisher: name: Freie Universität Berlin
Year: 2022
Subjects: subject: flow chemistry
subject: heterogeneous catalysis
subject: metallaphotoredox catalysis
subject: packed bed
subject: photochemistry
subject: 500 Naturwissenschaften und Mathematik::540 Chemie::540 Chemie und zugeordnete Wissenschaften

description: Metallaphotoredox catalysis is a powerful and versatile synthetic platform that enables cross-couplings under mild conditions without the need for noble metals. Its growing adoption in drug discovery has translated into an increased interest in sustainable and scalable reaction conditions. Here, we report a continuous-flow approach to metallaphotoredox catalysis using a heterogeneous catalyst that combines the function of a photo- and a nickel catalyst in a single material. The catalyst is embedded in a packed-bed reactor to combine reaction and (catalyst) separation in one step. The use of a packed bed simplifies the translation of optimized batch reaction conditions to continuous flow, as the only components present in the reaction mixture are the substrate and a base. The metallaphotoredox cross-coupling of sulfinates with aryl halides was used as a model system. The catalyst was shown to be stable, with a very low decrease of the yield (≈1% per day) during a continuous experiment over seven days, and to be effective for C–O arylations when carboxylic acids are used as nucleophile instead of sulfinates.
Electrostatic activation of prebiotic chemistry in substellar atmospheres
Creators: name: Stark, Craig R.
name: Helling, Christiane
name: Diver, Declan A.
name: Rimmer, Paul B.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Charged dust grains in the atmospheres of exoplanets may play a key role in the formation of prebiotic molecules, necessary to the origin of life. Dust grains submerged in an atmospheric plasma become negatively charged and attract a flux of ions that are accelerated from the plasma. The energy of the ions upon reaching the grain surface may be sufficient to overcome the activation energy of particular chemical reactions that would be unattainable via ion and neutral bombardment from classical, thermal excitation. As a result, prebiotic molecules or their precursors could be synthesised on the surface of dust grains that form clouds in exoplanetary atmospheres. This paper investigates the energization of the plasma ions, and the dependence on the plasma electron temperature, in the atmospheres of substellar objects such as gas giant planets. Calculations show that modest electron temperatures of $\approx 1$ eV ($\approx 10^{4}$ K) are enough to accelerate ions to sufficient energies that exceed the activation energies required for the formation of formaldehyde, ammonia, hydrogen cyanide and the amino acid glycine.
description: 18 pages, 3 figures. Accepted, The International Journal of Astrobiology
The hidden agglutinated foraminifera of the mid-Cretaceous hemipelagic carbonate deposits: A method–derived bias?
Creators: name: Besen, Richard M.
name: Hegert, Jasmin
name: Struck, Ulrich
Publisher: name: Freie Universität Berlin
Year: 2022
Subjects: subject: Formic acid
subject: Limestone
subject: Cretaceous
subject: Agglutinated foraminifera
subject: Method
subject: 500 Naturwissenschaften und Mathematik::560 Fossilien, Paläontologie::560 Paläontologie, Paläozoologie

description: Five different micropaleontological methods (H2O2, Glauber's salt, liquid nitrogen, acetic acid + Copper(ll) sulfate, and formic acid) were applied to study the differences of obtained agglutinated foraminiferal faunas of typical hemipelagic carbonate deposits of the mid-Cretaceous of Europe, and to prove whether there is a method–derived bias of knowledge about agglutinated foraminiferal faunas in these sedimentological settings. Split samples of the same weight were treated with each method to compare overall (calcareous + agglutinated) numbers of foraminifers per gram, numbers of agglutinated foraminifers per gram, and numbers of agglutinated foraminiferal genera per sample. The results show that the number of agglutinated foraminifers per gram strongly vary between 0.1 and 7.8 with use of standard micropaleontological methods. With application of formic acid, more agglutinated foraminifers per gram are obtained than with any other tested method. The number of agglutinated foraminifers per gram is 1.5 to 211.0 times higher in formic acid treated residues. Furthermore, with use of standard micropaleontological methods at least 2/3 of agglutinated foraminiferal genera and species are completely missing in these sedimentological settings. Consequently, standard micropaleontological methods are not applicable to study the whole agglutinated foraminiferal fauna, and a bias of knowledge and utility of agglutinated foraminifers in these sedimentological settings is obvious. A separate application of both acetic acid + Copper(II) sulfate and formic acid on samples is suggested for studies on the whole foraminiferal fauna, and a precise description of the applied method in studies is suggested.
In silico capture of noble gas atoms with a light atom molecule
Creators: name: Mebs, Stefan
name: Beckmann, Jens
Publisher: name: Freie Universität Berlin
Year: 2022
Subjects: subject: noble gas atoms
subject: in silico capture
subject: light atom molecule
subject: 500 Naturwissenschaften und Mathematik::540 Chemie::540 Chemie und zugeordnete Wissenschaften

description: Noble gas atoms (Ng = He, Ne, Ar, and Kr) can be captured in silico with a light atom molecule containing only C, H, Si, O, and B atoms. Extensive density functional theory (DFT) calculations on series of peri-substituted scaffolds indicate that confined spaces (voids) capable to energy efficiently encapsulate and bind Ng atoms are accessible by design of a tripodal peri-substituted ligand, namely, [(5-Ph2B-xan-4-)3Si]H (xan = xanthene) comprising (after hydride abstraction) four Lewis acidic sites within the cationic structure [(5-Ph2B-xan-4-)3Si]+. The host (ligand system) thereby provides an adoptive environment for the guest (Ng atom) to accommodate for its particular size. Whereas considerable chemical interactions are detectable between the ligand system and the heavier Ng atoms Kr and Ar in the host guest complex [(5-Ph2B-xan-4-)3Si·Ng]+, the lighter Ng atoms Ne and He are rather tolerated by the ligand system instead of being chemically bound to it, nicely highlighting the gradual onset of (weak) chemical bonding along the series He to Kr. A variety of real-space bonding indicators (RSBIs) derived from the calculated electron and pair densities provides valuable insight to the situation of an “isolated atom in a molecule” in case of He, uncovering its size and shape, whereas minute charge rearrangements caused by polarization of the outer electron shell of the larger Ng atoms results in formation of polarized interactions for Ar and Kr with non-negligible covalent bond contributions for Kr. The present study shows that noble gas atoms can be trapped by small light-atom molecules without the forceful conditions necessary using cage structures such as fullerenes, boranes and related compounds or by using super-electrophilic sites like [B12(CN)11]− if the chelating effect of several Lewis acidic sites within one molecule is employed.
Composite Higgs Boson in the Unified Subquark Model of All Fundamental Particles and Forces
Creators: name: Terazawa, Hidezumi
name: Yasue, Masaki
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: In the unified subquark model of all fundamental particles and forces, the mass of the Higgs boson in the standard model of electroweak interactions ($m_H$) is predicted to be about $2\sqrt{6}m_W/3$ (where $m_W$ is the mass of the charged weak boson), which agrees well with the experimental values of $125-126$ GeV recently found by the ATLAS and CMS Colaborations at the LHC. It seems to indicate that the Higgs boson is a composite of the iso-doublet subquark-antisubquark pairs well described by the unified subquark model with either one of subquark masses vanishing or being very small compared to the other.
description: 3 pages, published in Journal of Modern Physics Vol.5, No.5, 205-208 (2014). arXiv admin note: substantial text overlap with arXiv:1109.3705
Get Organized! A well-planned archival visit results in well-managed data
Creators: name: , Budke
name: , Noppe
Publisher: name: Zenodo
Year: 2022
Subjects: archives, research data management

description: How to plan for a fruitful archive visit and manage your research data every step of the way? This presentation introduces basic archive know-how, useful organization tools like Zotero and Tropy, and many tips and tricks for researchers heading into their first archival visit. Presented as part of the two-day workshop "From paper to files: how to efficiently digitize (historical) documents", which took place at KU Leuven on November 22-23, 2022. The workshop also introduced participants to other parts of a practical workflow for acquiring and processing physical archival materials, including photographing documents with cellphone cameras and performing optical character recognition (OCR) and handwritten text recognition (HTR) using tools like ABBYY Finereader and Transkribus.
An almost symmetric Strang splitting scheme for nonlinear evolution equations
Creators: name: Einkemmer, Lukas
name: Ostermann, Alexander
Publisher: name: arXiv
Year: 2013
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: In this paper we consider splitting methods for the time integration of parabolic and certain classes of hyperbolic partial differential equations, where one partial flow can not be computed exactly. Instead, we use a numerical approximation based on the linearization of the vector field. This is of interest in applications as it allows us to apply splitting methods to a wider class of problems from the sciences. However, in the situation described the classic Strang splitting scheme, while still a method of second order, is not longer symmetric. This, in turn, implies that the construction of higher order methods by composition is limited to order three only. To remedy this situation, based on previous work in the context of ordinary differential equations, we construct a class of Strang splitting schemes that are symmetric up to a desired order. We show rigorously that, under suitable assumptions on the nonlinearity, these methods are of second order and can then be used to construct higher order methods by composition. In addition, we illustrate the theoretical results by conducting numerical experiments for the Brusselator system and the KdV equation.
The Different Types of Unmanned Aerial Vehicle (UAV): Characteristics, Capabilities, and Challenges
Creators: name: Isa A.I.
name: Muhammad A. B
Publisher: name: gjrpublication
Year: 2024

description: Drones, or unmanned aerial vehicles (UAV), have transformed from military technology to civilian applications, transforming industries and daily life, with growing popularity among hobbyists, photographers, and professionals. UAVs support diverse uses, such as in digital agriculture and landmine detection. This paper x-rays and provides a comprehensive overview of the various types of UAVs, exploring their characteristics, capabilities, and applications.
Bored at home?—A systematic review on the effect of environmental enrichment on the welfare of laboratory rats and mice
Creators: name: Mieske, Paul
name: Hobbiesiefken, Ute
name: Fischer-Tenhagen, Carola
name: Heinl, Celine
name: Hohlbaum, Katharina
name: Kahnau, Pia
name: Meier, Jennifer
name: Wilzopolski, Jenny
name: Butzke, Daniel
name: Lewejohann, Lars
Publisher: name: Freie Universität Berlin
Year: 2022
Subjects: subject: animal behavior
subject: animal welfare
subject: enriched environment
subject: boredom
subject: abnormal behavior
subject: impoverished environment
subject: laboratory animals (mouse and rat)
subject: 600 Technik, Medizin, angewandte Wissenschaften::630 Landwirtschaft::630 Landwirtschaft und verwandte Bereiche

description: Boredom is an emotional state that occurs when an individual has nothing to do, is not interested in the surrounding, and feels dreary and in a monotony. While this condition is usually defined for humans, it may very well describe the lives of many laboratory animals housed in small, barren cages. To make the cages less monotonous, environmental enrichment is often proposed. Although housing in a stimulating environment is still used predominantly as a luxury good and for treatment in preclinical research, enrichment is increasingly recognized to improve animal welfare. To gain insight into how stimulating environments influence the welfare of laboratory rodents, we conducted a systematic review of studies that analyzed the effect of enriched environment on behavioral parameters of animal well–being. Remarkably, a considerable number of these parameters can be associated with symptoms of boredom. Our findings show that a stimulating living environment is essential for the development of natural behavior and animal welfare of laboratory rats and mice alike, regardless of age and sex. Conversely, confinement and under-stimulation has potentially detrimental effects on the mental and physical health of laboratory rodents. We show that boredom in experimental animals is measurable and does not have to be accepted as inevitable.
Propagation and neutrino oscillations in the base of a highly magnetized gamma-ray burst fireball flow
Creators: name: Fraija, Nissim
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Neutrons play an important role in the dynamics of gamma-ray bursts. The presence of neutrons in the baryon-loaded fireball is expected. If the neutrons abundance is comparable to that of protons, important features may be observed such as quasi-thermal multi-GeV neutrinos in coincidence with a subphotospheric $γ$-ray emission, nucleosynthesis at later times and rebrightening of the afterglow emission. Additionally, thermal MeV neutrinos are created by electron-positron annihilation, electron (positron) capture on protons (neutrons) and nucleonic bremsstrahlung. Although MeV neutrinos are difficult to detect, quasi-thermal GeV neutrinos are expected in km$^3$ detectors and/or DeepCore+IceCube. In this paper, we show that neutrino oscillations have outstanding implications for the dynamics of the fireball evolution and also that they can be detected through their flavor ratio on Earth. For that we derive the resonance and charged-neutrality conditions as well as the neutrino self-energy and effective potential up to order $m_W^{-4}$ at strong, moderate and weak magnetic field approximation to constrain the dynamics of the fireball. We found important implications: i) resonant oscillations are suppressed for high baryon densities as well as neutrons abundance larger than that of protons and ii) the effect of magnetic field is to decrease the proton-to-neutron ratio aside from the number of multi-GeV neutrinos expected in DeepCore detector. Also we estimate the GeV neutrino flavor ratios along the jet and on Earth.
description: ApJ, accepted. There was not changes with respect to the previous version
BRD4: a general regulator of transcription elongation
Creators: name: Altendorfer, Elisabeth
name: Mochalova, Yelizaveta
name: Mayer, Andreas
Publisher: name: Freie Universität Berlin
Year: 2022
Subjects: subject: RNA polymerase II
subject: transcription elongation
subject: promoter-proximal pausing
subject: BET proteins
subject: BRD4
subject: PROTAC
subject: 500 Naturwissenschaften und Mathematik::570 Biowissenschaften; Biologie::570 Biowissenschaften; Biologie

description: Transcription elongation by RNA polymerase II (Pol II) has emerged as a regulatory hub in gene expression. A key control point occurs during early transcription elongation when Pol II pauses in the promoter-proximal region at the majority of genes in mammalian cells and at a large set of genes in Drosophila. An increasing number of trans-acting factors have been linked to promoter-proximal pausing. Some factors help to establish the pause, whereas others are required for the release of Pol II into productive elongation. A dysfunction of this elongation control point leads to aberrant gene expression and can contribute to disease development. The BET bromodomain protein BRD4 has been implicated in elongation control. However, only recently direct BRD4-specific functions in Pol II transcription elongation have been uncovered. This mainly became possible with technological advances that allow selective and rapid ablation of BRD4 in cells along with the availability of approaches that capture the immediate consequences on nascent transcription. This review sheds light on the experimental breakthroughs that led to the emerging view of BRD4 as a general regulator of transcription elongation.
Prospective application of clinician-performed lung ultrasonography during the 2009 H1N1 influenza A pandemic: distinguishing viral from bacterial pneumonia
Creators: name: Tsung, James
name: Kessler, David Oren
name: Shah, Vaishali
Publisher: name: Columbia University
Year: 2012
Subjects: Epidemiology

description: Emergency department visits quadrupled with the initial onset and surge during the 2009 H1N1 influenza pandemic in New York City from April to June 2009. This time period was unique in that >90% of the circulating virus was surveyed to be the novel 2009 H1N1 influenza A according to the New York City Department of Health. We describe our experience using lung ultrasound in a case series of patients with respiratory symptoms requiring chest X-ray during the initial onset and surge of the 2009 H1N1 influenza pandemic. We describe a case series of patients from a prospective observational cohort study of lung ultrasound, enrolling patients requiring chest X-ray for suspected pneumonia that coincided with the onset and surge of the 2009 H1N1 influenza pandemic. Twenty pandemic 2009 H1N1 influenza patients requiring chest X-ray were enrolled during this time period. Median age was 6.7 years. Lung ultrasound via modified Bedside Lung Ultrasound in Emergency protocol assisted in the identification of viral pneumonia (n = 15; 75%), viral pneumonia with superimposed bacterial pneumonia (n = 7; 35%), isolated bacterial pneumonia only (n = 1; 5%), and no findings of viral or bacterial pneumonia (n = 4; 20%) in this cohort of patients. Based on 54 observations, interobserver agreement for distinguishing viral from bacterial pneumonia using lung ultrasound was ĸ = 0.82 (0.63 to 0.99). Lung ultrasound may be used to distinguish viral from bacterial pneumonia. Lung ultrasound may be useful during epidemics or pandemics of acute respiratory illnesses for rapid point-of-care triage and management of patients.
Top Quark as a Dark Portal and Neutrino Mass Generation
Creators: name: Ng, John N.
name: de la Puente, Alejandro
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We present a new model for radiatively generating Majorana active neutrino masses while incorporating a viable dark matter candidate. This is possible by extending the Standard Model with a single Majorana neutrino endowed with a dark parity, a colour electroweak singlet scalar, as well as a colour electroweak triplet scalar. Within this framework, the $up$-type quarks play a special role, serving as a portal for dark matter, and a messenger for neutrino mass generation. We consider three benchmark scenarios where the abundance of dark matter can match the latest experimental results, while generating neutrino masses in the milli-electronvolt range. We show how constraints from lepton flavour violation, in particular the branching fraction of $μ\to eγ$, can place lower bounds on the coupling between our dark matter candidate and top quarks. Furthermore, we show that this coupling can also be constrained using collider data from the Tevatron and the LHC.
description: 8 captions, 10 figures
Sputum completion and conversion rates after intensive phase of tuberculosis treatment: an assessment of the Rwandan control program
Creators: name: Kayigamba, Felix
name: Bakker, Mirjam
name: Mugisha, Veronicah
name: Gasana, Michel
name: Schim Van Der Loeff, Maarten
Publisher: name: Columbia University
Year: 2012
Subjects: Epidemiology
Medicine

description: In Rwanda tuberculosis (TB) is one of the major health problems. To contribute to an improved performance of the Rwandan National TB Control Program, we conducted a study with the following objectives: (1) to assess the completion rate of sputum smear examinations at the end of the intensive phase of TB treatment; (2) to assess the sputum conversion rate (SCR); (3) to assess associations between smear completion rate or SCR with key health facility characteristics. TB registers in 89 health facilities in five provinces were reviewed. Data of new and retreatment smear-positive pulmonary TB (PTB+) cases registered between January and June 2006 were included in the study. Data on key characteristics of the selected health facilities were also collected. Among 1509 new PTB + cases, 32 (2.1%) had died by 2 months, and 178 (11.8%) had been transferred-out. Among the remaining 1299 patients, a smear examination at month 2 was done in 1039 (smear completion rate 80.0%). Among these 1039, 852 (82.0%) had become smear-negative. The smear completion rate and SCR varied considerably between health facilities. A high number of new PTB cases at a health facility was the only significant predictor of a low completion rate, while the only independent factor associated with low sputum conversion rates was rural (vs. urban) location of the health facility. In Rwanda, too few patients get a smear examination after 2 months of TB treatment; the SCR among those with smear results was adequate at 82%. A high number of new TB patients at a health facility was a significant predictor of a low completion rate. The national TB control program should design strategies to improve completion rates.
Leveraging Mining Investments in Water Infrastructure for Broad Economic Development: Models, Opportunities and Challenges
Creators: name: Toledano, Perrine
name: Roorda, Clara
Publisher: name: Columbia University
Year: 2014
Subjects: Economics
Regional planning

description: Mining is increasing in moderate to high water risk areas and there mining operations are exacerbating the water stress of local communities and the environment, generating social disruptions and community disputes. The modalities of the allocation of water rights, coupled with strong environmental regulations advocating zero mine waste water discharge, will determine the potential for shared use. Shared use of water-related infrastructure means both: Diminishing the water footprint of mining companies (in quantity and/or quality), and increasing the water supplies to the community from alternative sources. By reducing its footprint, a mining company would be better prepared for a scenario of water scarcity, stronger regulation, higher water rights prices and communities’ opposition.
The Nature and Impact of Visual Perceptual Changes in Ageing and Dementia
Creators: name: Tyler, Samantha L.
Publisher: name: University of Leicester
Year: 2023
Subjects: Uncategorized

description: The purpose of this thesis was to assess the impact of healthy older age and older age with Alzheimer’s disease (AD) on the structural and functional integrity of the visual system and on key associated measures of visual performance. A systematic review of the literature (Chapter 2) revealed a significant impact of AD on the retina, where significant thinning in the ganglion cell layer of the retina, most commonly in superior and inferior retinal nerve fibre layer (RNFL) quadrants is consistently reported. Evidence of amyloid-β plaques in the lateral geniculate nuclei of the thalamus and in primary visual cortices (area V1) was also identified, accompanied by some evidence of gliosis in the magnocellular visual pathways and by neuron and glial cell loss in the parvocellular visual pathway. Reduced neural activation in areas V1 and V5/MT was also noted. In the context of visual performance, age and AD-related deficits have been reported in several visual domains including sensitivity to contrast, colour, depth, and motion. Self-report studies confirmed that dementia is associated with visual impairment and reduced vision-related quality of life beyond that experienced as part of the ‘typical’ aging process and that people with dementia are aware of the visual changes they experience (Chapter 3). The experiences of visual impairment by people with dementia were confirmed by their carers (Chapter 4). A series of clinical and psychophysical assessments of visual performance confirmed deleterious effects of AD on the visual system beyond that observed in healthy older age. This included AD-related deficits on fundamental aspects of visual perception, reflected by deficits on tests of colour discrimination and motion perception (Chapter 5). These effects extended to visual cognition, in particular to stimulus identification and visual search performance (Chapter 6).
ALMA Observations of the Coldest Place in the Universe: The Boomerang Nebula
Creators: name: Sahai, R.
name: Vlemmings, W. H. T.
name: Huggins, P. J.
name: Nyman, L-A.
name: Gonidakis, I.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The Boomerang Nebula is the coldest known object in the Universe, and an extreme member of the class of Pre-Planetary Nebulae, objects which represent a short-lived transitional phase between the AGB and Planetary Nebula evolutionary stages. Previous single-dish CO (J=1-0) observations (with a 45 arcsec beam) showed that the high-speed outflow in this object has cooled to a temperature significantly below the temperature of the cosmic background radiation. Here we report the first observations of the Boomerang with ALMA in the CO J=2-1 and J=1-0 lines to resolve the structure of this ultra-cold nebula. We find a central hourglass-shaped nebula surrounded by a patchy, but roughly round, cold high-velocity outflow. We compare the ALMA data with visible-light images obtained with HST and confirm that the limb-brightened bipolar lobes seen in these data represent hollow cavities with dense walls of molecular gas and dust producing both the molecular-emission-line and scattered-light structures seen at millimeter and visible wavelengths. The large diffuse biconical shape of the nebula seen in the visible is likely due to preferential illumination of the cold high-velocity outflow. We find a compact source of millimeter-wave continuum in the nebular waist -- these data, together with sensitive upper limits on the radio continuum using observations with ATCA, indicate the presence of a substantial mass of very large (mm-sized) grains in the waist of the nebula. Another unanticipated result is the detection of CO emission regions beyond the ultracold region which indicate the re-warming of the cold gas, most likely due to photoelectric grain heating.
description: accepted by the Astrophysical Journal (12 figures)
An evaluation of the brain distribution of [11C]GSK1034702, a muscarinic-1 (M1) positive allosteric modulator in the living human brain using positron emission tomography
Creators: name: Ridler, Khanum
name: Cunningham, Vincent
name: Huiban, Mickael
name: Martarello, Laurent
name: Pampols-Maso, Sabina
name: Passchier, Jan
name: Gunn, Roger
name: Searle, Graham
name: Abi-Dargham, Anissa
name: Slifstein, Mark
name: Watson, Jeanette
name: Laruelle, Marc
name: Rabiner, Eugenii
Publisher: name: Columbia University
Year: 2014
Subjects: subject: Psychiatry
subject: Neurosciences
subject: FOS: Clinical medicine

description: The ability to quantify the capacity of a central nervous system (CNS) drug to cross the human blood-brain barrier (BBB) provides valuable information for de-risking drug development of new molecules. Here, we present a study, where a suitable positron emission tomography (PET) ligand was not available for the evaluation of a potent muscarinic acetylcholine receptor type-1 (M1) allosteric agonist (GSK1034702) in the primate and human brain. Hence, direct radiolabelling of the novel molecule was performed and PET measurements were obtained and combined with in vitro equilibrium dialysis assays to enable assessment of BBB transport and estimation of the free brain concentration of GSK1034702 in vivo. GSK1034702 was radiolabelled with ¹¹C, and the brain distribution of [¹¹C]GSK1034702 was investigated in two anaesthetised baboons and four healthy male humans. In humans, PET scans were performed (following intravenous injection of [¹¹C]GSK1034702) at baseline and after a single oral 5-mg dose of GSK1034702. The in vitro brain and plasma protein binding of GSK1034702 was determined across a range of species using equilibrium dialysis.
The distribution of [¹¹C]GSK1034702 in the primate brain was homogenous and the whole brain partition coefficient (VT) was 3.97. In contrast, there was mild regional heterogeneity for GSK1034702 in the human brain. Human whole brain VT estimates (4.9) were in broad agreement with primate VT and the fP/fND ratio (3.97 and 2.63, respectively), consistent with transport by passive diffusion across the BBB.
In primate and human PET studies designed to evaluate the transport of a novel M1 allosteric agonist (GSK1034702) across the BBB, we have demonstrated good brain uptake and BBB passage consistent with passive diffusion or active influx. These studies discharged some of the perceived development risks for GSK1034702 and provided information to progress the molecule into the next stage of clinical development.
Simulation and Experimental Validation of Optical Camera Communication
Creators: name: Narasimman, Srivathsan Chakaravarthi
name: Alphones, Arokiaswami
Publisher: name: arXiv
Year: 2025
Subjects: subject: Signal Processing (eess.SP)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: While simulation tools for visible light communication (VLC) with photo detectors (PDs) have been widely investigated, similar tools for optical camera communication (OCC) with complementary metal oxide semiconductor (CMOS) sensors are lacking in this regard. Camera based VLC systems have much lower data rates owing to camera exposure times. Among the few extant OCC simulation tools, none allow for simulation of images when exposure time is greater than the signal period. An accurate simulation of the OCC system can be used to improve the data rate and quality of performance. We propose a simple simulation technique for OCC which allows to test for system performance at frequencies beyond the camera shutter speed. This will allow much needed data rate improvement by operating at the actual frequency a decoding algorithm ceases detection instead of the exposure limit used now. We have tested the accuracy of simulation by comparing the detection success rates of simulated images with experimental images. The proposed simulation technique was shown to be accurate through experimental validation for two different cameras.
Two rings but no fellowship: LoTr 1 and its relation to planetary nebulae possessing barium central stars
Creators: name: Tyndall, A. A.
name: Jones, D.
name: Boffin, H. M. J.
name: Miszalski, B.
name: Faedi, F.
name: Lloyd, M.
name: López, J. A.
name: Martell, S.
name: Pollacco, D.
name: Santander-García, M.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: LoTr 1 is a planetary nebula thought to contain an intermediate-period binary central star system (that is, a system with an orbital period, P, between 100 and, say, 1500 days). The system shows the signature of a K-type, rapidly rotating giant, and most likely constitutes an accretion-induced post-mass transfer system similar to other PNe such as LoTr 5, WeBo 1 and A70. Such systems represent rare opportunities to further the investigation into the formation of barium stars and intermediate period post-AGB systems -- a formation process still far from being understood. Here, we present the first detailed analyses of both the central star system and the surrounding nebula of LoTr 1 using a combination of spectra obtained with VLT-FORS2, AAT-UCLES and NTT-EMMI, as well as SuperWASP photometry. We confirm the binary nature of the central star of LoTr 1 that consists of a K1 III giant and a hot white dwarf. The cool giant does not present any sign of s-process enhancement but is shown to have a rotation period of 6.4 days, which is a possible sign of mass accretion. LoTr 1 also presents broad double-peaked H-alpha emission lines, whose origin is still unclear. The nebula of LoTr 1 consists in two slightly elongated shells, with ages of 17,000 and 35,000 years, respectively, and with different orientations. As such, LoTr 1 present a very different nebular morphology than A70 and WeBo 1, which may be an indication of difference in the mass transfer episodes
description: 16 pages, 12 figures. Accepted for publication in MNRAS
Enzymatic cleavage of histone H3: a new consideration when measuring histone modifications in human samples
Creators: name: Howe, Caitlin Grace
name: Gamble, Mary
Publisher: name: Columbia University
Year: 2015
Subjects: subject: Environmental health
subject: Genetics
subject: FOS: Biological sciences

description: Histone modifications are increasingly being used as biomarkers of cancer prognosis and survival. However, we identified a cleavage product of histone H3 in human peripheral blood mononuclear cells, which interferes with measures of certain H3 modifications. Therefore, the potential for enzymatic cleavage of histones should be considered when measuring histone modifications in human samples. Furthermore, the enzymatic cleavage of human H3 is itself a fascinating area of research and two important questions remain to be answered: 1) Does cleavage of human H3 occur in vivo, as it does in other organisms? and 2) Does it serve a biologically important function?