Moment Of Contact Research Articles

Two Cats, One Fish: The Animal,Leviathanand the Limits of Theory

Animals populate our artistic and philosophical discourses in critical ways. From Jacques Derrida's or Karen Barad's cat, to Donna Haraway's dog, to the fish in Lucien Castaing-Taylor and Véréna Paravel's Leviathan (2012), these animals feature heavily in discussions regarding limits – the limits of the human and thus its relation with non-humans, but also the limits of knowledge itself. Cute or dangerous, real or fantasised, dead or alive: in this article, I juxtapose the various ways that such animals confront us with what Jacques Derrida describes as “the point of view of the absolute other”. Similarly, recent texts stage encounters with animals – thus distributing agency towards a larger variety of beings, carving out space for a previously excluded non-human other. Yet these encounters are mediated in profoundly different ways. In researching how encounters with the animal are differentially inflected and “defracted” respective to the medium in which they are staged, this article invokes questions of form and style within the critical dialogue that attempts to centre non-human animals. Highlighting how formal decisions are not accidental, but rather integral, to the praxis of the philosophy of animality, this article aims to draw attention to how specific forms and styles allow for a moment of contact with a non-human other. To this end, this article examines three oft-cited encounters: Derrida's encounter with his cat, an intense stare with a fish in Leviathan, and Barad's inflection of Schrödinger's cat. This juxtaposition gives insight into the (ethical) limits of certain styles of producing thought and critically reflects on these works in their discussion of non-human life and agency.

Behavior characteristics of Janus particles impacting bubbles

In order to better apply amphiphilic Janus particles to phase change heat transfer, the hydrophilic-superhydrophobic Janus particles are prepared with copper balls. The particle size is 1.0 mm and the bubble diameter is 3.0 mm. The behavior of Janus particle with small bubbles impinging on bubbles at different heights is studied. The falling heights are 0, 10.0, 20.0, 30.0 and 40.0 mm. The results show that there are obvious differences in behavior characteristic among Janus particles with different wettability surfaces when they hit the bubble. When the superhydrophobic side contacts the bubble, it will slide to the bottom of the bubble without rotation along the bubble surface; when the hydrophilic side contacts the bubble, it will first slide along the bubble surface for a certain distance, and then rotate, resulting in strong disturbance to the bubble. When the interface between hydrophilic and superhydrophobic contacts the bubble, the particle will start to rotate at the moment of contact. When Janus particle impacts the bubble at a certain height, the hydrophilic surface generally contacts bubble first. With the increase of height, the degree of deformation of Janus particles pulling bubbles increases. The force analysis shows that the main reason for the rotation of Janus particles is that the action points and directions of capillary force acting on different wettable surfaces are different, resulting in corresponding rotation torque.

The collision of immiscible droplets in three-phase liquid systems: A numerical study using phase-field lattice Boltzmann method

A ternary phase-field LB model was employed in this paper to study the collision between two immiscible liquid droplets in a continuous liquid medium. Five different cases were considered based on droplets’ density, viscosity, and interfacial tension ratio. The results were presented in the form of We-B. (Weber number, and collision parameter) nomograms. The hydrodynamics of the interaction was analyzed by visualizing droplets’ deformation and behavior during the impact, especially in the contact area. Three collision outcomes were identified for both partial and total spreading states: engulfment (I), bounce (II), and engulfment with encapsulation of a tiny bulk liquid drop (III). The highest probability of the latter was seen at We > 50 and B < 0.5 for the cases in which droplets had equal density and viscosity. It was found that the satellite droplet encapsulation in regime (III) occurs for the deformed droplets as a result of a concave interface at the moment of contact. This in turn leads to the formation of two contact points and liquid bridges. No satellite formation was observed for the case where the density ratio between the droplets was relatively high. Moreover, a drastic decrease (≈35%) in the boundary between regimes (II) and (I) was observed in this case, compared to the cases where the interacting droplets had equal density. Performed simulations for collisions near the transition point from partial to complete engulfment revealed that the hydrodynamics of interaction and the collision regimes are similar in both cases, despite the difference in the final morphology of the compound.

Fatigue and recovery have different effects on knee biomechanics of drop vertical jump between female collegiate and recreational athletes

BackgroundAlthough fatigue is known as one of the risk factors for noncontact anterior cruciate ligament injury, the effects of fatigue and recovery can be different based on the level of competition. However, it is unknown whether female recreational athletes are susceptible to fatigue or not, compared to female collegiate athletes with greater physical activity. The purpose of the present study was to examine and clarify the effects of fatigue and recovery on knee biomechanics of the drop vertical jump (DVJ) in female recreational athletes compared to female collegiate athletes.MethodsFifteen female collegiate athletes and ten female recreational athletes were enrolled in the current study. All subjects were basketball players and Tegner activity scales were level 9 and 7, respectively. They performed DVJ before and after the fatigue protocol. Three-dimensional knee kinematics and kinetics were collected during landing phase of DVJ. The data after the fatigue protocol (first, second, and third DVJs) were compared with those before the protocol using one-way repeated measures of analysis of variance in each group.ResultsFatigue caused significant increase of knee abduction angle at initial contact (IC) and peak abduction moments within 40 ms from IC in female recreational athletes, whereas no increases of these parameters were observed in female collegiate athletes. Moreover, recovery from fatigue seemed to be more slowly in female recreational athletes than in female collegiate athletes as smaller knee flexion moment was observed even in post-fatigue third DVJ only for female recreational athletes.ConclusionsEffects of fatigue on DVJ were significantly greater and continued for a longer duration in female recreational athletes compared to female collegiate athletes.

Developing and exploring a methodology for multi-modal indoor and outdoor gait assessment.

Gait assessment is emerging as a prominent way to understand impaired mobility and underlying neurological deficits. Various technologies have been used to assess gait inside and outside of laboratory settings, but wearables are the preferred option due to their cost-effective and practical use in both. There are robust conceptual gait models developed to ease the interpretation of gait parameters during indoor and outdoor environments. However, these models examine uni-modal gait characteristics (e.g., spatio-temporal parameters) only. Previous studies reported that understanding the underlying reason for impaired gait requires multi-modal gait assessment. Therefore, this study aims to develop a multi-modal approach using a synchronized inertial and electromyography (EMG) signals. Firstly, initial contact (IC), final contact (FC) moments and corresponding time stamps were identified from inertial data, producing temporal outcomes e.g., step time. Secondly, IC/FC time stamps were used to segment EMG data and define onset and offset times of muscle activities within the gait cycle and its subphases. For investigation purposes, we observed notable differences in temporal characteristics as well as muscle onset/offset timings and amplitudes between indoor and outdoor walking of three stroke survivors. Our preliminary analysis suggests a multi-modal approach may be important to augment and improve current inertial conceptual gait models by providing additional quantitative EMG data.

The isolation room of the future: changing the perspective on isolated care

Abstract Antibiotic resistance is a growing problem worldwide. Several measures are taken when identified carriers of antibiotic resistant bacteria (such as MRSA) are admitted to a hospital: patients stay in an isolation room and healthcare workers have to put on personal protective equipment (PPE) before entering the isolation room. Previous research on experiences of isolated care shows that patients felt lonely, forgotten and stigmatized while healthcare personnel felt guilty for bundling their contact moments. Therefore, an innovation project has been set up to re-design the concept of an isolation room: the isolation room of the future. The isolation room of the future concentrates around providing enhancements for communication and interaction, comfort and accessibility and architecture and interior design, while taking into account the infection prevention regulations for isolation rooms in hospitals. The interior of the isolation room of the future consists of biophilic elements, including photo wallpaper, transparent walls, surfaces that mimic natural materials, and natural and dynamic light; creating a positive healing and working environment for patients, staff and visitors. Transparent walls also allow easy communication between patients and healthcare workers without the need for the PPE. Furthermore, a transfer hatch is installed to easily serve meals and drinks to the patient. A modular furniture set-up will ensure the most optimum use of space in the room. The isolation room of the future does not necessarily need to be built as a whole; specific elements can implemented depending on needs, finances and possibilities. We hope that these practical solutions might inspire healthcare facilities worldwide to re-think the concept of an isolation room to improve the experiences of people involved in isolated care. This approach is useful for a broader range of infections with pathogens that require isolation precautions, among which SARS-CoV-2. Key messages A change on perspective of isolated care is needed. Although based on experiences with resistant bacteria, the isolation room of the future useful for a broader range of infections with pathogens that require isolation precautions.

Возможные механизмы деструкции спор вакцинного штамма Bacillus anthracis СТИ-1 под воздействием спиртозолей наночастиц металлов

The results are presented of a comparative study of the sporicidal activity of alcohol sols of nanoparticles of titanium, copper, zinc and tantalum metals in the course of their interaction with a rehydrated lyophilized culture of spores of the vaccine strain Bacillus anthracis STI-1 with the loss of the ability of spores to germinate in nutrient media under optimal conditions using bacteriology and electronic microscopy. The most pronounced sporicidal effect is observed when titanium alcohol sol is exposed to spores. At the same time, spores of B. anthracis STI-1 in titanium alcohol sol are affected by ethyl alcohol, which causes dehydration and denaturation of the protein, the antiseptic cetylpyridinium chloride as a surfactant, which is also a strong electrophilic agent that destroys the exosporium and spore shells, and titanium nanoparticles, which, due to the high surface energy when exposed to spores, cause their pronounced massive adhesion. In addition, titanium nanoparticles, the zeta (? -) value of the potential of which is -44.5 mV, cause a stable energy state of the dispersed system of alcohol sol, which acts as a biocatalyst for intracellular enzymes, causing the hydrolysis of polymer structures of the spore shells and cortex, as well as destroyed nucleoid – an area of spores containing structured genetic material. Spores that do not have a nucleoid in electron microscopy acquire the form of "shadows". As a result of the action of titanium alcohol sol, the activation of germination and the formation of the so-called "metabolic" spores, from which the vegetative cells of B. anthracis STI-1 should have been formed, are prevented. The reason for the high sporicidal efficiency of the alcohol sol of titanium nanoparticles is associated both with the structure and properties and with the technology of synthesis of titanium nanoparticles in the low-temperature plasma zone with the formation, due to the excess of the surfactant cetylpyridinium chloride, of a two-layer shell around the metal nanoparticles, which leads to their "conservation" until the moment of contact with spores and a sharp slowdown in their oxidation in the aquatic environment. The destruction of the formed two-layer shell of metal nanoparticles begins with contact with spores with the simultaneous onset of the formation of titanium ions from the phase of nanoparticles, which actively destroy chemically the shells of the spores. Keywords: microorganisms, Bacillus anthracis STI-1, spores, metal nanoparticles, zeta potential, disinfectant compositions, sporicidal activity.

Characterisation and action mode of Gluconacin, a bacteriocin with antimicrobial activity against Xanthomonas albilineans

AbstractGluconacin, a bacteriocin produced by Gluconacetobacter diazotrophicus PAL5, has previously shown a large spectrum of inhibitory activity against beneficial and phytopathogenic bacteria. The present study proposes a three‐dimensional (3D) structure for Gluconacin based on modelling and describes some physicochemical characteristics and the effect of the peptide on cells of the phytopathogenic bacterium Xanthomonas albilineans ICMP196. The Gluconacin 3D structural model results demonstrated the 7 α‐helices and 11 β‐sheets. Growth inhibition of the indicator microorganism, X. albilineans, occurred in the first moments of contact with Gluconacin (0.25 μg μl−1). Treatment of bacterial cells caused significant loss of inorganic phosphate and UV‐absorbing materials. Scanning electron microscopy images showed that Gluconacin‐treated X. albilineans cells were fully lysed. These results suggest that the mode of action of this peptide involves altered membrane integrity and increased permeability, resulting in complete cell lysis. Physicochemical characterisation demonstrated stability of biological activity under high temperatures, including autoclaving conditions and low pH. The activity was reduced after treatment with proteases and some surfactants and abolished with ethylenediaminetetraacetic acid (EDTA). The 3D conformation model indicates the possibility of a hydrophobic region, which could possibly interact directly with the cell membrane of target bacteria. In conclusion, the ability of Gluconacin to inhibit growth of phytopathogens of agricultural importance opens up new opportunities for biotechnological applications and, consequently, a reduction in the use of pesticides.

ASSESSMENT OF PATIENT SATISFACTION WITH THE MEDICAL ORGANIZATION AND ITS SERVICES

The relevance of the problem under study is due to the fact that the medical organization must be aware of the target patient: to know who he is, how and why he wants to receive a particular medical service. All the information received and its analysis will allow us to develop a real scheme of mutually beneficial communication, convenient for each of the parties-the medical organization and the patient, which will allow us to reveal the weaknesses in the work and respond to them in a timely manner. The purpose of the study: to form an assessment of the patient's satisfaction with the medical organization and its services, taking into account the interest, feelings, purpose, arguments and thoughts that appear in the patient from the moment of the first contact with the clinic, with the display of the point of contact in graphic form, in order to minimize all possible obstacles in his route to receiving quality medical services and increasing the economic efficiency of the clinic.

COMPARATIVE CHARACTERISTICS OF COATINGS WITH SiO AND GeO ON LEUCOSAPPHIRE

The reasons for the sharp difference in the adhesion of multilayer coatings containing SiO or GeO together with Ge on a leucosapphire (Al2O3) plate have been established. It should be mentioned that Silicon(II) and Germanium(II) oxides are quite stable in the gaseous state and, contrary, are metastable in condensed state; at high temperature they disproportionate into ultra-dispersed composites of amorphous nature. A comparison is made of the surface properties of ultramicroscopic droplets formed on solid surfaces – a substrate or the previous layer – upon condensation of SiO, GeO, or Ge vapors on leucosapphire. A qualitative assessment of the ratio of the corresponding contact angles of wetting by the indicated melts, formed at the first moment of contact, has been carried out. In assessing the surface tension of SiO and GeO melts (or Si – SiO2 and Ge – GeO2 composites), we proceeded from the corresponding values for SiO2 and GeO2, which are 296 and 248 mJ/m2 near the crystallization temperatures. On this basis, it was established that the smallest value of the contact angle, and hence the best wetting, is observed for the GeO melt (somewhat less for the SiO melt) on the solid surface of Al2O3 or Ge; the solid surface of SiO or GeO (especially, the first of them) with molten germanium should be much weaker wetted. Hence, it follows that thin-film multilayer coatings obtained from Ge and GeO on a leucosapphire substrate should have a significantly higher climatic resistance due to higher adhesion compared to multilayer coatings from SiO and Ge. Indeed, a multilayer coating containing SiO on a leucosapphire substrate with a large surface can withstand storage in air for no more than 2–3 months and begins to peel off; at the same time, the GeO coating remains intact after 4 years of storage. Thus, the GeO film-forming material is a promising one for use in multilayer coatings such as cut-off filters in interference optics of the near and mid-IR spectral ranges.

The Process of Pregnancy: Paradoxical Temporalities of Prenatal Entities

In this article, we reflect on the particular temporal structure of pregnancies and prenatal entities with the aim to contribute to the field of the sociology of pregnancy. Medical models and technology shape today’s notion of pregnancy as a linear, nine-month developmental process that leads to the birth of a child. Through ultrasound technology and prenatal examinations, prenatal entities have thus historically gained a present ‘being’ as a developing, unborn child. While these ideas undoubtedly greatly influence the participants’ interpretations, a culturalistic perspective on time alone does not do justice to the phenomenon’s lived tensions and the temporal complexity of the phenomenon. From a Schutzian perspective of time, we have worked out how practices of pregnancy and the production of meaning are shaped by an interwoven back and forth between orientations to the past, present and future. Drawing on relevant works from the sociology of pregnancy, we work out five modes of temporal references that mold the phenomenon of pregnancy: joint imagination of the couple, in which the (un)born is anticipated as fantasies of the future (1), passivities of pregnancy, in which the desired future is experienced as unable to influence (2), the presentification of the unborn in and through visual and bodily-somatic contact moments (3), its futurization through the cultivation of a ‘not-yet’ (4) and prenatal losses, as a critical rupture with the anticipated and desired future (5). Our analysis underlines the potential of a time sociological perspective on pregnancy and the constitution of relationships and persons.

A spherical‐harmonic‐based approach to discrete element modeling of 3D irregular particles

AbstractDifferent from previous discrete element methods (DEM), where irregular 3D particle shapes are approximated by subspheres, vertices, or voxels, this study aims to develop an innovative and computationally effective DEM method directly employing spherical harmonic functions for simulations of 3D irregular‐shaped particles. First, the discrete surface points of a 3D irregular‐shaped particle are represented by spherical harmonic functions with only a limited number of harmonic coefficients to restore the particle morphology. Then, the intrinsic physical quantities are computed directly using spherical harmonic functions. Next, specific algorithms for interparticle overlapping detection and contact resolution involving the spherical harmonic functions are developed. Subsequently, the interparticle contact forces, moments, and particle movements are computed. The feasibility and capability of the proposed 3D method are verified by simulating random deposition of superellipsoids, repose angle tests, and triaxial tests on particles with various shapes. The proposed method could pave a viable pathway for realistic modeling of granular media pertaining to various engineering and industrial processes.

Spacecraft rendezvous and docking using measurements from satellite navigation equipment combined with the optical subsystem for final approach

The paper discusses an integrated system for spacecraft rendezvous and docking using measurements from satellite navigation equipment combined with the optical final approach subsystem (OFAS) which generates high-precision relative position vector during final approach It addresses issues involved in designing an OFAS which has to operate in an environment exposed to sunlight and provides an estimate for the accuracy of the relative position measurements depending on the current range and OFAS configuration. Simulations have been run of the final approach involving simultaneous control for m the satellite navigation equipment and OFAS. It was shown that at the moment of initial contact the approach accuracy of 2–5 cm for relative position, and of 1 cm/s for velocity is achieved. Key words: spacecraft, navigation, rendezvous, docking, final approach, satellite navigation, optical sensor, TV camera, control, precision.

THREE SOURCES – THREE COMPONENTS IN THE AREA OF GEOGRAPHICAL NAMES ENDING ON -LEI/-LYAI

The purpose of the scientific article is to establish the main historical sources of the inventory and subsequent comparative-historical interpretation of geographical names in the Oka and Sura regions, to compare three approaches to this problem, reflected in the works of well-known scientists: historian I.K. Engevatov, linguists G.P. Smolitskaya and D.V. Tsy­gankin. The results of the study in practical terms are designed to: 1) to enrich and update the relevant articles on onomatology and comparative studies of Finno-Ugric scholars, Turkologists and Slavists; 2) to clarify the views of historians and ethnologists/ ethno­graphers about specific moments of ethnic and linguistic contacts in Eastern Europe (in the Oka and the Sura regions). The results of the research in the future should initiate new works devoted to a particular class of geographical nomenclature terms in the historical perspective within the boundaries of the Slavic, Finno-Ugric and Turkic languages.

Comparative 3D DEM simulations of sand\u2013structure interfaces with similarly shaped clumps versus spheres with contact moments

Three-dimensional simulations of a monotonic quasi-static interface behaviour between initially dense cohesionless sand and a rigid wall of different roughness during tests in a parallelly guided direct shear test under constant normal stress are presented. Numerical modelling was carried out by the discrete element method (DEM) using clumps in the form of convex non-symmetric irregularly shaped grains. The clumps had an aspect ratio of 1.5. A regular grid of triangular grooves (asperities) along the wall with a different height at the same distance was assumed. The numerical results with clumps were directly compared under the same conditions with our earlier DEM simulations using pure spheres with contact moments with respect to the peak and residual interface friction angle, width of the interface shear zone, ratio between grain slips and grain rotations, distribution of contact forces and stresses. The difference between the behaviour of clumps and pure spheres with contact moments proved to be noticeable in the post-peak regime due to a different particle shape. The rolling resistance model with pure spheres was proved to be limited for capturing particle shape effects. Three different boundary conditions along the interface were proposed for micropolar continua, considering grain rotations and grain slips, wall grain moments and wall grain forces, and normalized interface roughness. The numerical results in this paper offer a better understanding of the interface behaviour of granular bodies in DEM and FEM simulations.

Road barriers: modern solutions for improving traffic safety

Improving the system of preventive measures aimed at reducing the severity of the consequences of road accidents is an urgent task. Road deaths are constantly increasing and there is a need for a comprehensive approach to creating safe road conditions. The purpose of this study is to analyze the promising designs of road barriers designed to prevent uncontrolled exit of vehicles from the roadway of the highway and to develop the design of energy-absorbing fencing. Barrier barriers must not only be safe for road users, but must also ensure their safety, as well as preserve the elements after hitting the fence. Analytical studies have shown that in order to reduce mechanical damage to vehicles and reduce the severity of injuries to the driver and passengers, it is necessary to develop a road fence design that allows you to extinguish the impact energy at the moment of contact between the car and the fence. Keywords: fencing, barrier, safety, traffic accident

Spacecraft rendezvous and docking using measurements from satellite navigation equipment combined with the optical subsystem for final approach

The paper discusses an integrated system for spacecraft rendezvous docking using measurements from satellite navigation equipment combined and with the optical final approach subsystem (OFAS) which generates high-precision relative 2Space Research Institute of the Russian Academy of Sciences (SRI RAS) 84/32 Profsoyuznaya str., Moscow, 117997, Russian Federation, e-mail: iki@cosmos.ru position vector during final approach. It addresses issues involved in designing an an on OFAS which has to operate in an environment exposed to sunlight and provides estimate for the accuracy of the relative position measurements depending the current range and OFAS configuration. Simulations have been run of the final approach involving simultaneous control from the satellite navigation equipment and OFAS. It was shown that at the moment of initial contact the approach accuracy of 2–5 cm for relative position, and of 1 cm/s for velocity is achieved.

Dynamics of contact electrification.

Although the electrical charging of objects brought into contact has been observed for at least 2000 years, the details of the underlying mechanism are still not yet fully understood. The present paper deals with the very basic process of contact electrification between two metals. We have developed an experimental method to follow the charge of a small sphere bouncing on a grounded planar electrode on a time scale down to 1 μs. It reveals that the sphere is discharged in the moment of contact, which lasts about 6 to 8 μs. However, at the very moment of disruption of the electrical contact, it regains charge far beyond the expectation according to the contact potential difference. The excess charge rises with increasing contact area.

The art of composing: between autonomy and heteronomy

The art of composing: between autonomy and heteronomy

An Experimental Study on the Impact of Contact Design on Web Survey Participation

In higher education institutions, web surveys are frequently used for educational, research, and administrative purposes. One of the consequences of this is increasing oversurveying of higher education students, leading to low response rates. This naturally has important implications for the validity of web survey results. Consequently, we set up a methodological experiment at Tilburg University, the Netherlands, whereby the total student population was invited to participate in a web survey in order to investigate which features of contact design can positively influence web survey participation. We particularly focus on subject line content, the communication of deadlines and their timing, as well as the delays between contact moments. The results reveal that students were more likely to respond to a web survey invitation when the subject line is written in the national language in multilingual contexts. Furthermore, although the findings did not indicate an advantage of using a deadline, they also suggested that if a deadline is to be used, a longer deadline might be more beneficial.