cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Identification of social groups and waiting pedestrians at railway platforms using trajectory data
Creators: name: Küpper, Mira
name: Seyfried, Armin
Publisher: name: arXiv
Year: 2023
Subjects: subject: Physics and Society (physics.soc-ph)
subject: FOS: Physical sciences

description: To investigate the impact of social groups on waiting behaviour of passengers at railway platforms a method to identify social groups through the monitoring of distances between pedestrians and the stability of those distances over time is introduced. The method allows the recognition of groups using trajectories only and thus opens up the possibility of studying crowds in public places without constrains caused by privacy protection issues. Trajectories from a railway platform in Switzerland were used to analyse the waiting behaviour of passengers in dependence of waiting time as well as the size of social groups. The analysis of the trajectories shows that the portion of passengers travelling in groups reaches up to 10\% during the week and increases to 20 \% on the weekends. 60\% of the groups were pairs, larger groups were less frequent. With increasing group size, the mean speed of the members decreases. Individuals and pairs often choose waiting spots at the sides of the stairs and in vicinity of obstacles, while larger groups wait close to the platform entries. The results indicate that passengers choose waiting places according to the following criteria and ranking: shortest ways, direction of the next intended action, undisturbed places and ensured communication. While individual passengers often wait in places where they are undisturbed and do not hinder others, the dominating comfort criterion for groups is to ensure communication. The results regarding space requirements of waiting passengers could be used for different applications. E.g. to enhance the level of service concept assessing the comfort of different types of users, to avoid temporary bottlenecks to improve the boarding and alighting process or to increase the robustness of the performance of railway platforms during peak loads by optimising the pedestrian distribution.
description: 15 pages, 8 figures, submitted to PLOS one
PROBLEMS OF INSURANCE MARKET DEVELOPMENT IN UKRAINE
Creators: name: Prylutskyi Аnatolii
Publisher: name: Colloquium-journal
Year: 2020
Subjects: insurance
insurance market
insurance companies
insurance payments
insurance premiums.

description: The necessity of insurance market functioning as one of the national economy strategic sectors is dis-cussed in the article. It is revealed that in addition to the implementation of the compensation function, insur-ance can greatly contribute to solving a number of state’s macroeconomic tasks by accumulating savings in the form of insurance premiums and turning them into investments. The estimation of insurance penetration level showed that modern insurance market of Ukraine is still at a rather low level of development. The main factors influencing the functioning of the insurance market in Ukraine are: the continuation of the military conflict in the country; restriction of consumer’s (insurers) effective demand due to the lower level of free income of the population and economic entities; devaluation of the national currency; loss of individual insurers’ deposits as a result of liquidation of a significant number of banking institutions; reduction of liquidity of the stock market, etc. Quantitative and qualitative analysis of the dynamics of the insurance companies main indicators of the performance showed that the Ukrainian insurance market the main indicators of development have a positive dynamics, but its functional and institutional characteristics in general do not correspond to the na-tional economy real needs. It is established that at present, the effective functioning of the insurance market in Ukraine is hampered by the lack of a unified state strategy regarding the development of the insurance services market in the country. Among other factors we can name the following: instability of the economic situation in the state; low level of insurance culture and financial education of citizens and participants of the insurance market; lack of liquid financial instruments for effective investment policy; low level of capitalization of do-mestic insurers (insufficient capitalization of insurance companies makes it impossible to insure large-scale risks in the energy, environmental and financial spheres); delay in introducing of compulsory medical, agrari-an and pension insurance with the participation of insurers; low level of services’ quality provided by individ-ual insurers, etc.
Sensing electric fields using single diamond spins
Creators: name: Dolde, Florian
name: Fedder, Helmut
name: Doherty, Marcus W.
name: Nöbauer, Tobias
name: Rempp, Florian
name: Balasubramanian, Gopalakrishnan
name: Wolf, Thomas
name: Reinhard, Friedemann
name: Hollenberg, Lloyd C. L.
name: Jelezko, Fedor
name: Wrachtrup, Jörg
Publisher: name: arXiv
Year: 2011
Subjects: subject: Quantum Physics (quant-ph)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: The ability to sensitively detect charges under ambient conditions would be a fascinating new tool benefitting a wide range of researchers across disciplines. However, most current techniques are limited to low-temperature methods like single-electron transistors (SET), single-electron electrostatic force microscopy and scanning tunnelling microscopy. Here we open up a new quantum metrology technique demonstrating precision electric field measurement using a single nitrogen-vacancy defect centre(NV) spin in diamond. An AC electric field sensitivity reaching ~ 140V/cm/\surd Hz has been achieved. This corresponds to the electric field produced by a single elementary charge located at a distance of ~ 150 nm from our spin sensor with averaging for one second. By careful analysis of the electronic structure of the defect centre, we show how an applied magnetic field influences the electric field sensing properties. By this we demonstrate that diamond defect centre spins can be switched between electric and magnetic field sensing modes and identify suitable parameter ranges for both detector schemes. By combining magnetic and electric field sensitivity, nanoscale detection and ambient operation our study opens up new frontiers in imaging and sensing applications ranging from material science to bioimaging.
Contributing to the development of community-based knowledge translation through the creation, implementation and evaluation of a youth mental health promotion initiative
Creators: name: Jenkins, Emily K.
Publisher: name: University of British Columbia
Year: 2015

description: Background: Mental health challenges have been identified as the most significant health issue facing young people. Leaders in the field have advocated for public health approaches to better address this issue. Some scholars have called for interventions informed by young people to enhance relevance and effectiveness of interventions. Knowledge translation (KT) has emerged in the health context as a strategy to promote the uptake of evidence to improve health outcomes; however, the majority of KT research to date has focused on clinical settings. The needs of researchers and practitioners working in community settings to address population-level health outcomes have not been adequately attended to, leading to calls for further development of community-based knowledge translation (CBKT), an approach underpinned by the tenets of participatory research and KT. Given these gaps, the purpose of this research was to contribute to the field of CBKT through the development, implementation and evaluation of a youth-driven mental health promotion initiative. Methods: This study utilized a case study design and was conducted in a rural community located in North-Central British Columbia, Canada. A mixed methods approach incorporating quantitative surveys, qualitative interviews and ethnographic field notes was used to examine the contextual factors associated with adolescent mental health, develop a CBKT framework to inform future work in this field, and assess the influence of a CBKT initiative on youth mental health. Findings: Findings demonstrate ways in which adolescent mental health may be influenced by contextual factors, evidence that can be used to inform change efforts to improve youth mental health. Further, a theoretically-driven and evidence-informed CBKT framework is introduced and used to illustrate how it can inform context-relevant, youth-driven initiatives. The CBKT approach utilized was shown to make a contribution to enhancing positive aspects of mental health such as resilience and connectedness among young people. Further, this approach was linked by study participants to changes at a community-level that foster mental health outcomes such as civic engagement, shifting norms and empowerment. Conclusions: CBKT shows promise as an approach to addressing one of the leading public health issues facing young people today, mental health challenges.
THE EFFECT OF MILK THISTLE, METHIPHEN AND SILIMEVIT ON THE VITAMINS A AND E LEVEL IN THE BLOOD OF LAYING HENS IN EXPERIMENTAL CHRONIC CADMIUM TOXICOSIS
Creators: name: Ostapyuk A.Y.
name: Gutyj B.V.
name: Hunchak V.M.
name: Leskiv Kh.Ya.
name: Khariv I.I.
name: Vasiv R.O.
name: Kamratska O.І.
Publisher: name: Colloquium-journal
Year: 2020
Subjects: toxicology
cadmium
bird
blood
silymevit
methiphen
milk thistle.

description: The research aimed to investigate the effect of milk thistle, methiphene and silimevit on the vitamins A and E level in the blood of laying hens in experimental chronic cadmium toxicosis. 32 сhickens, 78 weeks old, were selected for the analysis. Four groups were formed: control and three experimental. Chickens of the control group (C) and three experimental groups were administrated with water cadmium sulfate at a dose of 4 mg/kg body weight. Poultry of the experimental group (E1) were supplied the fruits of milk thistle at a dose of 2.0 g / kg of feed once a day for 30 days. Birds of the experimental group (E2) were fed metifen at a dose of 0.28 g / kg of feed once a day for 30 days. Chickens of experimental group E3 were added silimevit at a dose of 0.36 g / kg of feed once a day for 30 days. It was found that with the development of chronic cadmium toxicosis in poultry, the vitamins A and E content in their blood decreases throughout the test. The administration to chickens un-der cadmium load of milk thistle, methiphen and silimevit increases the vitamins A and E level in their blood. When silymevit was used on laying hens, the level of vitamins in their blood was the highest compared with the use of methefen and milk thistle.
High-Angular Resolution Dust Polarization Measurements: Shaped B-field Lines in the Massive Star Forming Region Orion BN/KL
Creators: name: Tang, Ya-Wen
name: Ho, Paul T. P.
name: Koch, Patrick M.
name: Rao, Ramprasad
Publisher: name: arXiv
Year: 2010
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present observational results of the thermal dust continuum emission and its linear polarization in one of the nearest massive star-forming sites Orion BN/KL in Orion Molecular Cloud-1. The observations were carried out with the Submillimeter Array. With an angular resolution of 1" (~2 mpc; 480 AU), we have detected and resolved the densest cores near the BN/KL region. At a wavelength of ~870 micron, the polarized dust emission can be used to trace the structure of the magnetic field in this star-forming core. The dust continuum appears to arise from a V-shaped region, with a cavity nearly coincident with the center of the explosive outflows observed on larger scales. The position angles (P.A.s) of the observed polarization vary significantly by a total of about 90 degree but smoothly, i.e., curl-like, across the dust ridges. Such a polarization pattern can be explained with dust grains being magnetically aligned instead of mechanically with outflows, since the latter mechanism would cause the P.A.s to be parallel to the direction of the outflow, i.e., radial-like. The magnetic field projected in the plane of sky is therefore derived by rotating the P.A.s of the polarization by 90 degree. We find an azimuthally symmetric structure in the overall magnetic field morphology, with the field directions pointing toward 2.5" west to the center of the explosive outflows. We also find a preferred symmetry plane at a P.A. of 36 degree, which is perpendicular to the mean magnetic field direction (120 degree) of the 0.5 pc dust ridge. Two possible interpretations of the origin of the observed magnetic field structure are discussed.
description: 27 pages, 7 figures; ApJ in press
THE SODIUM SELENITE AND FEED ADDITIVE “METISEVIT PLUS” EFFECT ON THE MORPHOLOGICAL PARAMETERS OF THE BLOOD OF RATS IN CADMIUM AND LEAD INTOXICATION
Creators: name: Slobodian S.О.
name: Gutyj B.V.
name: Leskiv Kh.Ya.
name: Khariv, I.I.
name: Paziuk I., S.
Publisher: name: Colloquium-journal
Year: 2020
Subjects: toxicology
rats
cadmium
lead
sodium selenite
Metisevit plus.

description: Lead and cadmium are among the influential environmental pollutants today. The results of many experi-mental studies indicate that in mammals Cadmium and Lead have a toxic effect on many organs and systems. The research aimed to study the impact of sodium selenite and feed additive “Metisevit Plus” on the morpho-logical parameters of the blood of rats under cadmium and lead intoxication. The analyses were performed on male Wistar rats weighing 200–220 g, from which 3 groups of animals were formed: control (C) and two exper-imental (E1), (E2). Mice of the (C) and (E1), (E2) groups were injected with 16.6% lead acetate aqueous solution at a dose of 100 mg/kg and 0.029% cadmium chloride aqueous solution at a dose of 2.0 mg/kg. Rats of the (E1) group were additionally administered sodium selenite at a dose of 0.2 mg/kg body weight. Animals of the (E2) group were additionally given a feed additive “Metisevit plus” at a dose of 0.5 mg/kg body weight. Sodium selenite and feed additive “Metisevit plus” contributes to the normalization of morphological parameters of the blood in spite of the development of chronic lead-cadmium toxicosis. However, it should be noted that the better normalizing effect of the blood is feed additive “Metisevit Plus” on the morphological parameters of the blood than the sodium selenite in animals.
Measurement of the Compton scattering in germanium with a p-type point-contact germanium detector for dark matter detection
Creators: name: Hu, J. W.
name: Yang, L. T.
name: Yue, Q.
name: Geng, X. P.
name: Li, H. B.
name: Liang, Y. F.
name: Lin, S. T.
name: Liu, S. K.
name: Ma, H.
name: Wang, L.
name: Wong, H. T.
name: Zhang, B. T.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Low-energy background through Compton scattering from the ambient $γ$ rays can be contaminated in direct dark matter search experiments. In this paper, we report comparable measurements on low-energy spectra via Compton scattering from several $γ$-ray sources with a p-type point-contact germanium detector. The spectra between 500 eV and 18 keV have been measured and analyzed. Moreover, the features of the electron binding effect, particularly at the edges of the K- and L-shells in the germanium atom, were observed with different gamma sources and were consistent with the models in the Geant4 simulation. An empirical background model is proposed that provides insights into understanding the low-energy background in germanium for direct dark matter experiments.
description: 7 pages, 5 figures and 2 tables; version accepted by JINST
TO ASSESS THE BIOCIDAL ACTION OF THE DRUG BASED ON SODIUM HYPOCHLORITE.
Creators: name: Soltys, M.P.
name: Gunchak, V.M.
name: Rudyk, G.V.
name: Gutyj, B.V.
name: Brezvin, O.M.
name: Vasiv, R.O.
Publisher: name: Colloquium-journal
Year: 2020
Subjects: biocides
sodium hypochlorite
bactericidal
fungicidal
sporocidal action.

description: The article presents data on the antiseptic and disinfectant effect of the drug «Vitosept». The peculiarity of this biocidal product is that the active substance in it is high-purity sodium hypochlorite, obtained in a spe-cially designed diaphragm-free flow electrolyzer using isotonic sodium chlorite solution prepared in water purified by a separate technology. In the course of the conducted researches it was found out that the investigated remedy has the expressed bactericidal, fungicidal and sporocidal properties. Its high bactericidal activity against E. coli, S. aureus, P. aeruginosa has been established. There was a decrease in the number of microorganisms by 6.5-7.5 lg in the first 30 minutes of contact both in the presence of organic matter (5% bovine albumin B.S.A.) and in its ab-sence. Resistance of A. niger to «Vitosept», in the presence of high organic load (5% of bovine albumin-B.S.A.) allows to recommend a differentiated approach to the mode of disinfection in mycosis foci; to wipe twice with an interval of 15 minutes, and when immersed in 60 minutes to replace «Vitosept» and keep the items in solu-tion for 30 minutes. It was confirmed that when disinfecting objects contaminated with fungi, it is necessary to use higher concentrations of the studied drug and increase the duration of contact, in particular, the concen-tration should be maintained at 600 mg / l for more than three hours. The use of lower concentrations is not appropriate, because it requires a long period of action and does not guarantee the desired result. Increasing the temperature of «Vitosept» to 50 ° C and keeping it at this level for 30 minutes dramatically increases the sporicidal activity of the drug. In this case, the time required for sterilization is reduced several times. However, given the technical difficulties associated with heating, the use of the temperature factor can be considered as one of the possible options.
A triangulation of $\CC P^3$ as symmetric cube of $S^2$
Creators: name: Bagchi, Bhaskar
name: Datta, Basudeb
Publisher: name: arXiv
Year: 2010
Subjects: subject: Algebraic Topology (math.AT)
subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 57Q15, 57R05, 57M60

description: The symmetric group $S_3$ acts on $S^2 \times S^2 \times S^2$ by coordinate permutation, and the quotient space $(S^2 \times S^2 \times S^2)/S_3$ is homeomorphic to the complex projective space $\CC P^3$. In this paper, we construct an 124-vertex simplicial subdivision $(S^2 \times S^2 \times S^2)_{124}$ of the 64-vertex standard cellulation $S^2_4 \times S^2_4 \times S^2_4$ of $S^2 \times S^2 \times S^2$, such that the $S_3$-action on this cellulation naturally extends to an action on $(S^2 \times S^2 \times S^2)_{124}$. Further, the $S_3$-action on $(S^2 \times S^2 \times S^2)_{124}$ is "good", so that the quotient simplicial complex $(S^2 \times S^2 \times S^2)_{124}/S_3$ is a 30-vertex triangulation $\CC P^3_{30}$ of $\CC P^3$. In other words, we construct a simplicial realization $(S^2 \times S^2 \times S^2)_{124} \to \CC P^3_{30}$ of the branched covering $S^2 \times S^2 \times S^2 \to \CC P^3$. Finally, we apply the BISTELLAR program of Lutz on $\CC P^3_{30}$, resulting in an 18-vertex 2-neighbourly triangulation $\CC P^3_{18}$ of $\CC P^3$. The automorphism group of $\CC P^3_{18}$ is trivial. It may be recalled that, by a result of Arnoux and Marin, any triangulation of $\CC P^3$ requires at least 17 vertices. So, $\CC P^3_{18}$ is close to vertex-minimal, if not actually vertex-minimal. Moreover, no explicit triangulation of $\CC P^3$ was known so far.
description: 29 pages
Studies of Rhodobacter capsulatus gene transfer agent recipient capability regulated by quorum-sensing and the CtrA response regulator
Creators: name: Brimacombe, Cedric
Publisher: name: University of British Columbia
Year: 2015

description: Gene transfer agents (GTAs) are agents of genetic exchange that resemble small tailed DNA bacteriophages and transfer random segments of the producing cell's genome to recipient cells. The canonical GTA is produced by the α-proteobacterium Rhodobacter capsulatus, hereafter referred to as RcGTA. The RcGTA packages ~4 kb segments of genomic DNA, and is produced and released by the lysis of a sub-population of donor cells in the stationary phase of growth. The primary structural gene cluster is a ~ 15 kb genomic region. Production and release of RcGTA is regulated by several host systems, including the GtaI quorum-sensing system, and the CckA/ChpT/CtrA putative phosphorelay system. Prior to this work, studies on RcGTA focused primarily on aspects involved in the production of RcGTA particles, such as gene regulation, DNA packaging, and biological functionality. However essentially nothing was known about how RcGTA delivers DNA to recipient cells. Herein, several key aspects of the capability of a cell to receive an RcGTA carried genetic marker, defined as RcGTA recipient capability, are delineated. Initial studies on the GtaR/I quorum-sensing system showed that gtaR/I are co-transcribed, and indirectly regulate not only transcription of the RcGTA gene cluster, but also RcGTA recipient capability. Part of this quorum-sensing effect was attributed to regulation of capsular polysaccharide production, which was determined to be involved in RcGTA adsorption to cells. Additionally, it was found that CtrA is essential for, and a regulator of several genes required for RcGTA recipient capability. CtrA was found to regulate a set of natural competence genes involved in DNA entry into the cell and in RecA-mediated homologous recombination. These genes, DprA, ComM, ComEC, and ComF, are all essential for RcGTA recipient capability, and analyses of the encoded proteins were used to propose a pathway for acquisition of RcGTA-borne DNA. These findings indicate that the RcGTA horizontal gene transfer mechanism is a combination of two fundamentally different horizontal gene transfer (HGT) mechanisms, transduction and transformation, generating a very efficient mode of HGT.
Relative In-flight Response of IBEX-Lo to Interstellar Neutral Helium Atoms
Creators: name: Swaczyna, P.
name: Bzowski, M.
name: Fuselier, S. A.
name: Galli, A.
name: Heerikhuisen, J.
name: Kubiak, M. A.
name: McComas, D. J.
name: Möbius, E.
name: Rahmanifard, F.
name: Schwadron, N. A.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Space Physics (physics.space-ph)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The IBEX-Lo instrument on the Interstellar Boundary Explorer (IBEX) mission measures interstellar neutral (ISN) helium atoms. The detection of helium atoms is made through negative hydrogen (H$^-$) ions sputtered by the helium atoms from the IBEX-Lo conversion surface. The energy spectrum of ions sputtered by ISN helium atoms is broad and overlaps the four lowest IBEX-Lo electrostatic analyzer (ESA) steps. Consequently, the energy response function for helium atoms does not correspond to the nominal energy step transmission. Moreover, laboratory calibration is incomplete because it is difficult to produce narrow-energy neutral atom beams that are expected for ISN helium atoms. Here, we analyze the ISN helium observations in ESA steps 1-4 to derive the relative in-flight response of IBEX-Lo to helium atoms. We compare the ratios of the observed count rates as a function of the mean ISN helium atom energy estimated using the Warsaw Test Particle Model (WTPM). The WTPM uses a global heliosphere model to calculate charge exchange gains and losses to estimate the secondary ISN helium population. We find that the modeled mean energies of ISN helium atoms, unlike their modeled fluxes, are not very sensitive to the very local interstellar medium parameters. The obtained relative responses supplement the laboratory calibration and enable more detailed quantitative studies of the ISN helium signal. A similar procedure that we applied to the IBEX-Lo observations may be used to complement laboratory calibration of the next-generation IMAP-Lo instrument on the Interstellar Mapping and Acceleration Probe (IMAP) mission.
description: 17 pages, 8 figures, 1 table, accepted for publication in ApJS
Social workers’ experience working with families with children facing death
Creators: name: Wilkey, Lisa
Publisher: name: University of British Columbia
Year: 2015

description: This study addressed the question: “What meaning do social workers give to their experience of working with families with children facing death?” Its purpose was to explore the meaning social workers attach to their unique professional role in this particular area of practice. Four social work participants from a children’s hospital were recruited, chosen because of their experience in working directly with this population. Criteria for inclusion were a minimum education level of a Master’s Degree in Social Work and at least two years of experience working in the hospital setting. A qualitative descriptive approach, drawing on phenomenology, was utilized. Each participant was individually interviewed for one hour using a semi-structured format. A phenomenological approach to data analysis was used. After careful review, four areas of meaning-making emerged: what brought participants to this work; meaning-making within the function of the role; connection and companionship; and, challenges faced within the role. These results add to the relatively small base of knowledge regarding the experience of social workers who work in pediatric end-of-life care in a healthcare setting.
The mass-loss return from evolved stars to the Large Magellanic Cloud V. The GRAMS carbon-star model grid
Creators: name: Srinivasan, Sundar
name: Sargent, Benjamin A.
name: Meixner, Margaret
Publisher: name: arXiv
Year: 2011
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The total dust return rate from AGB and RSG star outflows is an important constraint to galactic chemical evolution models. However, this requires detailed radiative transfer (RT) modeling of individual stars, which becomes impractical for large data sets. Another approach is to select the best-fit spectral energy distribution (SED) from a grid of dust shell models, allowing for a faster determination of the luminosities and mass-loss rates for entire samples. We have developed the Grid of RSG and AGB ModelS (GRAMS) to measure the mass-loss return from evolved stars. The models span the range of stellar, dust shell and grain properties relevant to evolved stars. In this paper we present the carbon-star grid and compare our results with data of Large Magellanic Cloud (LMC) carbon stars from the SAGE and SAGE-Spec programs. We generate spherically symmetric dust shell models using the 2Dust code, with hydrostatic models for the central stars. We explore five values of the inner radius R_in of the dust shell (1.5, 3, 4.5, 7 and 12 R_star). We use amorphous carbon dust mixed with 10% silicon carbide by mass. The grain sizes follows a KMH distribution. The models span 26 values of 11.3 um optical depth, ranging from 0.001 to 4. For each model, 2Dust calculates the output SED from 0.2 to 200 um. Over 12,000 models have dust temperatures below 1800 K. The GRAMS synthetic photometry is in good agreement with SAGE photometry for LMC carbon-rich and extreme AGB star candidates, as well as spectroscopically confirmed carbon stars from the SAGE-Spec study. Our models reproduce the IRAC colors of most of the extreme AGB star candidates, consistent with the expectation that a majority of these enshrouded stars have carbon-rich dust. Finally, we fit the SEDs of some well-studied carbon stars and compare the resulting luminosities and mass-loss rates with those from previous studies.
description: 16 pages, 13 figures, accepted for publication in Astronomy & Astrophysics
Phase-transition microcavity laser
Creators: name: Yang, Xi
name: Tang, Shui-Jing
name: Meng, Jia-Wei
name: Zhang, Pei-Ji
name: Chen, You-Ling
name: Xiao, Yun-Feng
Publisher: name: arXiv
Year: 2023
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Liquid-crystal microcavity lasers have attracted considerable attention because of their extraordinary tunability and sensitive response to external stimuli, and they operate generally within a specific phase. Here, we demonstrate a liquid-crystal microcavity laser operated in the phase transition, in which the reorientation of liquid-crystal molecules occurs from aligned to disordered states. A significant wavelength shift of the microlaser is observed, resulting from the dramatic changes in the refractive index of liquid-crystal microdroplets during the phase transition. This phase-transition microcavity laser is then exploited for sensitive thermal sensing, enabling two-order-of-magnitude enhancement in sensitivity compared with the nematic-phase microlaser operated far from the transition point. Experimentally, we demonstrate an exceptional sensitivity of -40 nm/K and an ultrahigh resolution of 320 uK. The phase-transition microcavity laser features compactness, softness, and tunability, showing great potential for high-performance sensors, optical modulators, and soft matter photonics.
description: 15 pages, 4 figures
Stable Bound Orbits around Black Rings
Creators: name: Igata, Takahisa
name: Ishihara, Hideki
name: Takamori, Yohsuke
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We examine bound orbits of particles around singly rotating black rings. We show that there exist stable bound orbits in toroidal spiral shape near the axis of the ring, and also exist stable circular orbits on the axis as special cases. The stable bound orbits can have arbitrary large size if the thickness of the ring is less than a critical value.
description: 9 pages, 7 figures
Adaptation ecologies : circuits of climate change finance, policy, and science in the Pacific Islands
Creators: name: Webber, Sophie Rachel
Publisher: name: University of British Columbia
Year: 2015

description: In order to address the expected impacts of climate change, international development institutions have instigated adaptation projects and policies. These efforts promise to mitigate anticipated harms in vulnerable-to-climate-change social and ecological systems. This dissertation examines the operation and dissemination of adaptation projects and policies in the context of small island states in the Pacific region. It also explores the important role that the pre-eminent development institution, the World Bank, plays in programming adaptation. The research questions explored here are: i) How do finance, policy and science circulate in the name of adaptation? ii) What do the circulation of finance, policy and science achieve for adaptation in Kiribati and Solomon Islands? and iii) Why is the World Bank invested in adaptation, or what does adaptation do for the World Bank and other developmental actors? In answering these questions, I draw from multi-sited primary fieldwork, participant observation, and documentary analysis: at the World Bank in Washington, DC and Sydney, within the public bureaucracies of Australia, Kiribati, and Solomon Islands, and with regional organizations and development partners in the Pacific region. This dissertation posits the emergence of a Pacific Adaptation Complex. The analytical concept of the Pacific Adaptation Concept recognizes the vast institutional arrangements, configurations of expertise, and project technologies that come together to make adaptation happen. Within the Complex, experimental nodes are key, as are multi-directional flows. Yet, I find that, overwhelmingly, flows and investments for adaptation are dogged by persistent stickiness, and a rhetorical attention to mobility and success that is indifferent to practical outcomes. However, the promise of adaptation finance, policy, and science works through failing development institutions and imaginaries, allowing reinvention in an era of development crisis.
Single and double inclusive particle production in d+Au collisions at RHIC, leading twist and beyond
Creators: name: Albacete, Javier L.
name: Marquet, Cyrille
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We discuss the evidence for the presence of QCD saturation effects in the data collected in d+Au collisions at RHIC. In particular we focus our analysis on forward hadron yields and azimuthal correlations. Approaches alternative to the CGC description of these two observables are discussed in parallel.
description: 20 pages ann 9 figures. Contribution to the proceedings of the Workshop "Saturation, the Color Glass Condensate and Glasma: What Have we Learned from RHIC?", May 10-12 2010, Brookhaven National Laboratory, USA
Additional file 1 of Migration of pre-induced human peripheral blood mononuclear cells from the transplanted to contralateral eye in mice
Creators: name: Huang, Jianfa
name: Xian, Bikun
name: Peng, Yuting
name: Zeng, Baozhu
name: Li, Weihua
name: Li, Zhiquan
name: Xie, Yaojue
name: Zhao, Minglei
name: Zhang, Hening
name: Zhou, Minyi
name: Yu, Huan
name: Wu, Peixin
name: Liu, Xing
name: Huang, Bing
Publisher: name: figshare
Year: 2021
Subjects: subject: Medicine
subject: Cell Biology
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Neuroscience
subject: Physiology
subject: Pharmacology
subject: Biotechnology
subject: Chemical Sciences not elsewhere classified
subject: Immunology
subject: FOS: Clinical medicine
subject: Developmental Biology
subject: Cancer
subject: Science Policy
subject: Hematology

description: Additional file 1.
Trajectory control in idealized four-wave mixing processes in optical fiber
Creators: name: Sheveleva, Anastasiia
name: Colman, Pierre
name: Dudley, J. M.
name: Finot, Christophe
Publisher: name: arXiv
Year: 2023
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: The four-wave mixing process is a fundamental nonlinear interaction in Kerr media that can be described by a closed trajectory in the associated phase plane. We show here that it is possible to manipulate these trajectories and to connect two points that are not part of the same orbit. Our approach is based on a localized abrupt modification of the average power of the system. This mechanism is confirmed using different experimental realizations where iterative propagation in a short fiber segments mimics propagation in an idealized optical fiber.
Combined effects of STDP and homeostatic structural plasticity on coherence resonance
Creators: name: Yamakou, Marius E.
name: Kuehn, Christian
Publisher: name: arXiv
Year: 2023
Subjects: subject: Neurons and Cognition (q-bio.NC)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: FOS: Biological sciences
subject: FOS: Physical sciences

description: Efficient processing and transfer of information in neurons have been linked to noise-induced resonance phenomena such as coherence resonance (CR), and adaptive rules in neural networks have been mostly linked to two prevalent mechanisms: spike-timing-dependent plasticity (STDP) and homeostatic structural plasticity (HSP). Thus, this paper investigates CR in small-world and random adaptive networks of Hodgkin-Huxley neurons driven by STDP and HSP. Our numerical study indicates that the degree of CR strongly depends, and in different ways, on the adjusting rate parameter $P$, which controls STDP, on the characteristic rewiring frequency parameter $F$, which controls HSP, and on the parameters of the network topology. In particular, we found two robust behaviors: (i) Decreasing $P$ (which enhances the weakening effect of STDP on synaptic weights) and decreasing $F$ (which slows down the swapping rate of synapses between neurons) always leads to higher degrees of CR in small-world and random networks, provided that the synaptic time delay parameter $τ_c$ has some appropriate values. (ii) Increasing the synaptic time delay $τ_c$ induces multiple CR (MCR) -- the occurrence of multiple peaks in the degree of coherence as $τ_c$ changes -- in small-world and random networks, with MCR becoming more pronounced at smaller values of $P$ and $F$. Our results imply that STDP and HSP can jointly play an essential role in enhancing the time precision of firing necessary for optimal information processing and transfer in neural systems and could thus have applications in designing networks of noisy artificial neural circuits engineered to use CR to optimize information processing and transfer.
description: 15 pages, 5 figures, 86 references
Nanophotonic Enhancement and Improved Electron Extraction in Perovskite Solar Cells Using Near-Horizontally Aligned TiO2 Nanorods
Creators: name: Thakur, Ujwal K.; Zeng, Sheng; Kumar, Pawan; Patel, Sahil; Kisslinger, Ryan; Zhang, Yun; Kar, Piyush; Goswami, Ankur; Thundat, Thomas; Meldrum, Alkiviathes; Shankar, Karthik
Publisher: name: University of Alberta Libraries
Year: 2018

Abstract
Large electropositive cations as surfactants for the growth of polar epitaxial films
Creators: name: Cheung, Alfred Ka Chun
Publisher: name: University of British Columbia
Year: 2015

description: Using density functional theory (DFT) we demonstrate that the adsorption of large cations such as potassium or cesium facilitates the epitaxial growth of polar LaAlO₃ (LAO) on SrTiO₃ (STO). The low ionization potential of K favors efficient electron transfer to the STO conduction band and results in a 2D electron gas which exactly compensates for the diverging potential with increasing layer thickness. For large cations like K or Cs, DFT total energy considerations show that they remain adsorbed on the LAO surface and do not enter substitutionally into LAO. These results suggest a novel scheme for growing clean LAO/STO interface systems, and polar systems in general, by performing the growth process in the presence of large, low ionization potential alkali metal ions.
Decoherent phonon effects in fast atom-surface scattering
Creators: name: Frisco, L.
name: Gravielle, M. S.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Understanding the influence of phonon-mediated processes on grazing-incidence fast atom diffraction (GIFAD) patterns is relevant for its use as a surface analysis technique. In this work, we apply the Phonon-Surface Initial Value Representation (P0-SIVR) approximation to study lattice vibration effects on GIFAD patterns for the He-LiF(001) system at room temperature. The P0-SIVR approach is a semiquantum method that describes the zero-phonon atom-surface scattering including the contribution of intermediate phonon transitions. The main features introduced by thermal lattice vibrations in the angular distributions of the scattered helium atoms are investigated by considering normal energies in the 0.1 -3 eV range. In all the cases, thermal fluctuations introduce a wide polar spread that transforms the interference maxima into elongated strips. We found that the polar width of these fringes does not depend on the normal energy, as it was experimentally observed. In addition, when the normal energy increases, not only the relative intensities of interference peaks are affected by the crystal vibrations, but also the visibility of the interference structures, which disappear completely for normal energies approximately equal to or higher than 3 eV. These findings agree fairly well with the experimental data reported in Phys. Chem. Chem. Phys. 237615 (2021). However, it should be noticed that the simulated polar widths underestimate the experimentally-derived limit, suggesting that there are other mechanisms, such as inelastic phonon processes, that contribute to the polar dispersion of the GIFAD patterns.
description: 7 pages, 6 figures
Economics of In-Space Industry and Competitiveness of Lunar-Derived Rocket Propellant
Creators: name: Metzger, Philip
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Economics (econ.GN)
subject: Physics and Society (physics.soc-ph)
subject: FOS: Economics and business
subject: FOS: Physical sciences

description: Economic parameters are identified for an in-space industry where the capital is made on one planet, it is transported to and teleoperated on a second planet, and the product is transported off the second planet for consumption. This framework is used to model the long-run cost of lunar propellant production to help answer whether it is commercially competitive against propellant launched from Earth. The prior techno-economic analyses (TEAs) of lunar propellant production had disagreed over this. The "gear ratio on cost" for capital transport, G, and the production mass ratio of the capital, phi, are identified as the most important factors determining competitiveness. The prior TEAs are examined for how they handled these two metrics. This identifies crucial mistakes in some of the TEAs: choosing transportation architectures with high G, and neglecting to make choices for the capital that could achieve adequate phi. The tent sublimation technology has a value of phi that is an order of magnitude better than the threshold for competitiveness even in low Earth orbit (LEO). The strip mining technology is closer to the threshold, but technological improvements plus several years of operating experience will improve its competitiveness, according to the model. Objections from members of the aerospace community are discussed, especially the question whether the technology can attain adequate reliability in the lunar environment. The results suggest that lunar propellant production will be commercially viable and that it should lower the cost of doing everything else in space.
description: To be published in Acta Astronautica. 50 pages, 16 figures
The First Multiband Photometric Light Curve Solutions of the V Gru Binary System from the Southern Hemisphere
Creators: name: Tanriver, Mehmet
name: Poro, Atila
name: Bulut, Ahmet
name: Keskin, Ahmet
name: Blackford, Mark G.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The first multiband photometric solutions of the short-period V Gru eclipsing binary from the southern hemisphere is presented in this study. Light curves of the system were observed through BVI filters at the Congarinni Observatory in Australia for 15 nights. In addition to the new ground-based data, we also used the TESS observations in two sectors. We analyzed the light curves of the system using the PHysics Of Eclipsing BinariEs (PHOEBE) 2.4.7 version code to achieve the best accordance with the photometric observations. The solutions suggest that V Gru is a near-contact binary system with q=1.302(81) mass ratio, f1=0.010(23), f2=-0.0.009(21), and i=73.45(38). We considered the two hot spots on the hotter and cooler components for the light curve analysis. We extracted the minima times from the light curves based on the Markov Chain Monte Carlo (MCMC) approach. Using our new light curves, TESS, and additional literature minima, we computed the ephemeris of V Gru. The system's eclipse timing variation trend was determined using the MCMC method. This system is a good and challenging case for future studies.
description: Accepted by the Research in Astronomy and Astrophysics (RAA) journal
Galaxy cluster studies with weak lensing magnification & shear
Creators: name: Ford, Jessica Lange
Publisher: name: University of British Columbia
Year: 2015

description: Clusters of galaxies offer a unique window for studying the Universe on the largest scales. As the most massive gravitationally bound systems to have formed, they serve as probes of the large-scale distributions of dark matter, the underlying cosmology, and the complicated intracluster physics that characterizes the evolution of these massive systems. Gravitational lensing is the deflection of light coming from distant sources, by gravitational potentials along its path. Being sensitive to all mass regardless of type or dynamical state, lensing is a valuable tool for studying dark matter and characterizing galaxy clusters. In the weak lensing regime, the very slight apparent distortion of galaxy shapes is referred to as the shear, while the focusing and amplification of light is referred to as the magnification. The former has become a well-developed and robust technique in astronomy over the past decade, but the latter has been largely overlooked until now. The work embodied in this thesis includes the first-ever significant detection of magnification by galaxy groups, and the first comparison between masses measured with weak lensing magnification and shear (Chapter 2). This is followed by an application to an enormous sample of galaxy clusters, yielding ground-breaking signal-to-noise for magnification and an analysis of redshift-dependent systematic effects. This project also provides measurements of the cluster mass-richness scaling relation, and is a milestone in moving from magnification detection to useful science (Chapter 3). Finally, a comprehensive gravitational lensing shear analysis is performed on the previous cluster sample, allowing for a critical comparison between cluster masses measured with the independent techniques, as a function of both richness and redshift. These shear measurements also allow for important constraints on a new sample of galaxy clusters, including the distribution of cluster centroid offsets, the mass-richness relation, and cluster redshift evolution (Chapter 4). This thesis details unprecedented measurements using a new technique -- weak lensing magnification -- and comparisons with the well-studied shear approach. The final product exemplifies the promise of the new method for measuring galaxy cluster masses, and also points to likely issues that will need to be addressed in future experiments.