Peculiar Point Research Articles

New type of cavitation instability with peculiar frequency characteristic in liquid rocket inducer

In a liquid rocket turbopump with low pressure and thin wall tanks, cavitation inevitably occurs at the inducer which is installed at the inlet of the turbopump. The cavities at each blade oscillate periodically, and the turbopump sometimes becomes unstable, called cavitation instability. Rotating cavitation is one of the common types of cavitation instability, in which the cavities at each inducer blade oscillate respectively and appear to propagate from blade to blade. However, the new type of cavitation instability which does not follow the conventional principle has been observed in our experiment with an inducer. Converting the frequency in the inertial frame to that in the rotational frame and organizing it in the cavitation number, it was found that the frequency of unsteady cavitation increases as the cavitation number decreases, and this is the peculiar point of this instability. Additionally, during the cavitation instability, a few numbers of backflow vortex cavities were observed and moved sub-synchronously from blade to blade. In addition, the tip leakage vortex cavitation on each blade also propagates like sub-synchronous rotating cavitation but in different propagation speed from that of the backflow vortex cavities. As a result, it was supposed that the new instability is one of the types of sub-synchronous rotating cavitation related to backflow vortex cavitation, tip leakage vortex cavitation, and interaction between cavity propagation and inducer blade.

Vortex supersolid in the XY model with tunable vortex fugacity

In this paper, we investigate the XY model in the presence of an additional potential term that independently tunes the vortex fugacity favouring their nucleation. By increasing the strength of this term and thereby the vortex chemical potential µ, we observe significant changes in the phase diagram with the emergence of a normal vortex-antivortex lattice as well as a superconducting vortex-antivortex crystal (lattice supersolid) phase. We examine the transition lines between these two phases and the conventional non-crystalline one as a function of both the temperature and the chemical potential. Our findings suggest the possibility of a peculiar tricritical point where second-order, first-order, and infinite-order transition lines meet. We discuss the differences between the present phase diagram and previous results for two-dimensional Coulomb gas models. Our study provides important insights into the behaviour of the modified XY model and opens up new possibilities for investigating the underlying physics of unconventional phase transitions.

Vortex-antivortex pair creation in black hole thermodynamics

An isolated critical point is a peculiar thermodynamic critical point that occurs in the phase diagram of hyperbolic black holes in Kth-order Lovelock gravity in higher dimensions (with K odd) for special tuned Lovelock coupling constants. It corresponds to a "merger" of two swallowtails and is characterized by non-standard critical exponents. Upon employing a recent proposal for assigning a topological charge to thermodynamic critical points, we argue that the isolated critical point offers an interpretation corresponding to the onset of a topological phase transition of a "vortex/anti-vortex pair".

Peculiar points of aqueous solutions of mono-hydrogen alcohols

The work is devoted to the detailed study of the peculiar points in aqueous solutions of mono-hydrogen alcohols. The main attention is focused on water-methanol and water–ethanol solutions for which there are numerous experimental data. It is taken into account that H-bond interaction between alcohol and water molecules stimulates the formation of hydration complexes or elementary clusters, stable for temperatures: T<42°C. A solution at the peculiar point has a cell-like structure, where every cell consists of one alcohol molecule surrounded by water molecules forming mono-molecular layer. The volume and dissolution heat per cluster are determined. It is shown that the peculiar point arises at the concentration leading to the full filling of a solution by elementary clusters. The instability of elementary clusters near the peculiar point is considered. The possible existence of peculiar point of another type is discussed.

Association Between Kinematic Center and Anatomy, The Function of Temporomandibular Joint

Background: Evident from the literature, the kinematic center (KC) has been proposed as a reference point for representing movements of the TMJ, which includes jaw openings, closings, and protrusions and retrusions. Objective: The purpose of this study was to determine whether the KC lies in a peculiar anatomical point and whether its trajectory reflects intra-articular distances. Methods: Dynamic stereo-metry was used to track Four closings and openings and Four protrusions/retrusion in fourteen asymptomatic individuals (8 females and 6 males, ages 21-40). Results: According to a 3D lattice (0.5 mm grid) constructed solidly around each condyle, the KC had the largest cross-correlation between protrusion-retrusion paths and opening-closing paths. On closing, KC trajectories were more cranial than on opening, consistent with smaller intraarticular distances on closing. Yet KCs never fell on main condylar axes (distance, 4.5 mm) or coincided with points approximating fossa shapes (distance, 12.5 mm). Conclusion: In this regard, it is unclear what the significance of the kinematic center is anatomically and functionally.

Exploring the Topography of the Authoritarian: Populism, Illiberalism, and Authoritarianism

“Democratic regression,” the “retreat of western liberalism,” the “return” or “renaissance” of authoritarianism or the “third wave of autocratization” − these are some the many labels for diverse phenomena − or problems of authority − that plague societies in the Global North and South. Commonly, such problems of authority are specified as pathological practices of corruption or institutional defects, deviant forms of governance or pathological symptoms of representation and participation. Their semantic specification and interpretive framework are delivered by three camps − with contested, porous borders and considerable intersections and agreements − under the signifier illiberalism, populism or authoritarianism. All of them claim, each camp speaking from its peculiar vantage point, the authority to interpret the phenomena mentioned above. In this article the “properties” − advantages and failures − of the three frameworks are discussed and brought into a conversation with one another.

Orí, Ayé and the ontogeny of society

ABSTRACT It is difficult for any scholar on Yoruba culture to escape contact with the extensive literature on Orí, a metaphysical, ontological predicate for the existence of human selfhood, and self-other relations. This is not only because much has been written on the subject by scholars of different disciplinary persuasions, but also because this scholarship claims to be advancing, a peculiar point of view that originates a new way of looking at situation in terms of certain local categories and possibilities of action. Yoruba belief that Orí is that to which other deities (for it could be raised as a deity) should defer: all, except God, the maker of all things. Thus, it is reverenced, because it is about the self and because it cannot be reduced to any position of inferiority in any human actions.

Laser Micro-Irradiation to Study DNA Recruitment During S Phase.

DNA damage repair maintains the genetic integrity of cells in a highly reactive environment. Cells may accumulate various types of DNA damage due to both endogenous and exogenous sources such as metabolic activities or UV radiation. Without DNA repair, the cell's genetic code becomes compromised, undermining the structures and functions of proteins and potentially causing disease. Understanding the spatiotemporal dynamics of the different DNA repair pathways in various cell cycle phases is crucial in the field of DNA damage repair. Current fluorescent microscopy techniques provide great tools to measure the recruitment kinetics of different repair proteins after DNA damage induction. DNA synthesis during the S phase of the cell cycle is a peculiar point in cell fate regarding DNA repair. It provides a unique window to screen the entire genome for mistakes. At the same time, DNA synthesis errors also pose a threat to DNA integrity that is not encountered in non-dividing cells. Therefore, DNA repair processes differ significantly in S phase as compared to other phases of the cell cycle, and those differences are poorly understood. The following protocol describes the preparation of cell lines and the measurement of dynamics of DNA repair proteins in S phase at locally induced DNA damage sites, using a laser-scanning confocal microscope equipped with a 405 nm laser line. Tagged PCNA (with mPlum) is used as a cell cycle marker combined with an AcGFP-labeled repair protein of interest (i.e., EXO1b) to measure the DNA damage recruitment in S phase.

Laser Micro-Irradiation to Study DNA Recruitment During S Phase

DNA damage repair maintains the genetic integrity of cells in a highly reactive environment. Cells may accumulate various types of DNA damage due to both endogenous and exogenous sources such as metabolic activities or UV radiation. Without DNA repair, the cell's genetic code becomes compromised, undermining the structures and functions of proteins and potentially causing disease. Understanding the spatiotemporal dynamics of the different DNA repair pathways in various cell cycle phases is crucial in the field of DNA damage repair. Current fluorescent microscopy techniques provide great tools to measure the recruitment kinetics of different repair proteins after DNA damage induction. DNA synthesis during the S phase of the cell cycle is a peculiar point in cell fate regarding DNA repair. It provides a unique window to screen the entire genome for mistakes. At the same time, DNA synthesis errors also pose a threat to DNA integrity that is not encountered in non-dividing cells. Therefore, DNA repair processes differ significantly in S phase as compared to other phases of the cell cycle, and those differences are poorly understood. The following protocol describes the preparation of cell lines and the measurement of dynamics of DNA repair proteins in S phase at locally induced DNA damage sites, using a laser-scanning confocal microscope equipped with a 405 nm laser line. Tagged PCNA (with mPlum) is used as a cell cycle marker combined with an AcGFP-labeled repair protein of interest (i.e., EXO1b) to measure the DNA damage recruitment in S phase.

Afterword: sectarianisation beyond the Middle East

ABSTRACT Sectarianisation, a conceptual approach proposed by Nader Hashemi and Danny Postel, has gained a great deal of traction in the study of sectarianism in the contemporary Middle East. Yet despite its popularity, little attention has been paid to the ways in which sectarianisation can operate beyond the Middle East, a peculiar point when considering that only 20% of the world’s 1.57 billion Muslims live in the region. This brief intervention explores the ways in which the sectarianisation thesis can operate beyond the Middle East, looking at some of the ontological, epistemological, and methodological questions that are bound up in such an approach. Ultimately, I argue that while sectarianism has become a prominent feature in academic discussions about the Middle East – driven recently by a focus on sectarianisation – there is merit in exploring the application of Hashemi and Postel’s thesis in regions beyond the Middle East.

The Kepler problem: the energy point, the Levi-Civita, the Burdet and the KS regularizations via the primigenial sphere

In our unitary description (Vivarelli in Meccanica 50:915–925, 2015) of the Kepler problem (obtained via the introduction of a simple structure, the primigenial sphere $$S_{p^{-1}}$$), we have shown that this sphere encompasses, in a sort of inbred order of its elements, several fundamental elements of the Kepler problem. In this paper, we show that also the mechanical energy of an elliptic Kepler orbit is an element embedded in the sphere through a peculiar point, the energy point $$P^*$$. We show that this point in its circular motion on the sphere has a velocity which is strictly linked to so-called Sundman–Levi-Civita regularizing time transformation (Levi-Civita in Opere matematiche, 1973). Moreover in this spherical scenario, we reconsider both the two regularizations of the Kepler problem, namely the Bohlin–Burdet (Burdet in Z Angew Math Phys 18:434–438, 1967) and the Kustaanheimo and Stiefel (KS) regularizations (J Reine Angew Math 218:204–219, 1965): we present a geometrical interpretation of the first one, and we show an explicit link between their regularizing fundamental equations.

Magnetic-Competition-Induced Colossal Magnetoresistance in n -Type HgCr2Se4 under High Pressure

The n-type HgCr_{2}Se_{4} exhibits a sharp semiconductor-to-metal transition (SMT) in resistivity accompanying the ferromagnetic order at T_{C}=106 K. Here, we investigate the effects of pressure and magnetic field on the concomitant SMT and ferromagnetic order by measuring resistivity, dc and ac magnetic susceptibility, as well as single-crystal neutron diffraction under various pressures up to 8GPa and magnetic fields up to 8T. Our results demonstrate that the ferromagnetic metallic ground state of n-type HgCr_{2}Se_{4} is destabilized and gradually replaced by an antiferromagnetic, most likely a spiral magnetic, and insulating ground state upon the application of high pressure. On the other hand, the application of external magnetic fields can restore the ferromagnetic metallic state again at high pressures, resulting in a colossal magnetoresistance (CMR) as high as ∼ 3×10^{11}% under 5T and 2K at 4GPa. The present study demonstrates that n-type HgCr_{2}Se_{4} is located at a peculiar critical point where the balance of competition between ferromagnetic and antiferromagnetic interactions can be easily tipped by external stimuli, providing a new platform for achieving CMR in a single-valent system.

Canal Zone Modernism

AbstractThis essay is a narrowly drawn exercise in comparison at a narrow passage of marine transit—the Panama Canal Zone. It argues that the spatial typology of the “zone” might supply one of the figures for a tropological history of comparative modernism at sea. The essay follows disparate works—by the Swiss avant-garde poet Blaise Cendrars, the West Indian writers Claude McKay and Eric Walrond, the Nicaraguan poet Ernesto Cardenal, and the American modernist poet Wallace Stevens—into the space of conflicts and disparities that characterizes the Canal Zone as a peculiar choke point of maritime globalization.

Destroy the planet for the sake of the very rich? A plea for fair distribution as common sense

This paper will address from a peculiar point of view the key issue -raised today by Greta Thunberg and her peers- of the unlimited economic growth in a limited planet. It is its aim to point out how a relentless growth, while entailing dramatic ecological consequences in terms both of resources’ consumption/destruction and of climate change, contrary to a common perception does not benefit everybody. In contrast, because of the unequal distribution of GDP and wealth that is largely driven by the legal systems such as politically shaped, it benefits only the very rich. This new understanding should finally lead the vast majority of us to stop asking for an unlimited growth and to join Greta Thunberg in her protest, calling for something different, namely a less unequal redistribution of what we have via different legal rules. Why in fact should we destroy the planet, such as weneed it for our survival, just to make the very wealthy even more affluent?

Networks or Structures? Organizing Cultural Routes Around Heritage Values. Case Studies from Poland

The most common way of managing cultural heritage recently takes form of cultural routes as they seem to offer a new model of participation in culture to their recipients; they are often a peculiar anchor point for inhabitants to let them understand their identity and form the future; they offer actual tours to enter into interaction with culture and history, to build together that creation of the heritage, which so is becoming not only a touristic product, but, first of all, the space for cultural, social and civic activity. Yet, so far, according to what we know, the research problem concerning the method of cultural route organization (points on the route) into solid structures or more of the networked nature, has not been deliberated. A question arises, what values are brought by routes and how to organize routes to be the carriers of the values important for communities, where routes are functioning. And, as a consequence, if, from the point of view of the values of local communities, organizing solid route structures or organizing more widely-spaced, network-based routes would bring effects and what those effects would be. Thus, the posed question is of course scientifically imprecise because a network is a type of structure but presents a given direction for the development of cultural route structures. Our objective here is to present a certain solidity and rigidity of structure with dynamic and smooth understanding of the network. The research presented in the article is based on 3 case studies. We have selected for this purpose the three largest cultural routes in Poland, organized to various degrees. The outcome of the research was referred also to other cultural route organization research.

On almost continuous functions and peculiar points

We introduce the concept of a peculiar point (of the first and second kind), which combines stability of functions around a given point on a large set in the sense of Lebesgue measure with strong chaos of a function (in the sense of its entropy value) around this point. We prove that almost continuity of a function is equivalent to the fact that in every Gamma -neighbourhood of this function one can find a continuous function having a peculiar point either of the first or second kind.

Qualitative Analysis of Clustering in Aqueous Alcohol Solutions

The specific features of clustering in the aqueous solutions of monohydric alcohols with concentrations higher than that at the peculiar point are discussed. Clustering is a result of the formation of hydrogen bonds between water and alcohol molecules, the energy of which some-what exceeds the energy of hydrogen bonds in the water-water and alcohol-alcohol molecular pairs. Elementary clusters are assumed to be formed, whose composition is fixed at the solution concentrations lower than that at the peculiar point and changes according to a certain law at higher concentrations. The solution clustering degree was determined as a function of the solution concentration and the temperature.

Point clouds by SLAM-based mobile mapping systems: accuracy and geometric content validation in multisensor survey and stand-alone acquisition

The paper provides some operative replies to evaluate the effectiveness and the critical issues of the simultaneous localisation and mapping (SLAM)-based mobile mapping system (MMS) called ZEB by GeoSLAM™ https://geoslam.com/technology/. In these last years, this type of handheld 3D mapping technology has increasingly developed the framework of portable solutions for close-range mapping systems that have mainly been devoted to mapping the indoor building spaces of enclosed or underground environments, such as forestry applications and tunnels or mines. The research introduces a set of test datasets related to the documentation of landscape contexts or the 3D modelling of architectural complexes. These datasets are used to validate the accuracy and informative content richness about ZEB point clouds in stand-alone solutions and in cases of combined applications of this technology with multisensor survey approaches. In detail, the proposed validation method follows the fulfilment of the endorsed approach by use of root mean square error (RMSE) evaluation and deviation analysis assessment of point clouds between SLAM-based data and 3D point cloud surfaces computed by more precise measurement methods to evaluate the accuracy of the proposed approach. Furthermore, this study specifies the suitable scale for possible handlings about these peculiar point clouds and uses the profile extraction method in addition to feature analyses such as corner and plane deviation analysis of architectural elements. Finally, because of the experiences reported in the literature and performed in this work, a possible reversal is suggested. If in the 2000s, most studies focused on intelligently reducing the light detection and ranging (LiDAR) point clouds where they presented redundant and not useful information, contrariwise, in this sense, the use of MMS methods is proposed to be firstly considered and then to increase the information only wherever needed with more accurate high-scale methods.

영어와 한국어의 전제 유발체 비교 분석

The purpose of this paper is to survey and analyze the difference on presupposition-triggers of English and Korean. It is a phenomenon that the presupposition is created in the dialogue between the speaker and the listener in all languages. The presupposition in English and Korean was able to confirm the presupposition-triggers in terms of lexical, syntactical, and pragmatical. Although Karttunen(1974) and Levinson(2013) classify the presuppositiontriggers in detail, in this paper, English were divided into five lexical, five syntactical, two pragmatical presupposition-triggers. In Korean, only 6 lexical, 5 syntactical, and 1 pragmatical presupposition-triggers were analyzed. What is unusual is that in order to understand Korean pragmatical presuppositiontriggers, it is necessary to understand felicity conditions first. In addition, one peculiar point in the presupposition-triggers of English and Korean is that the English is the center of the verb, while the Korean is the center of the verb and the noun. It is an absolutely different part of English that proper nouns are used as presupposition-triggers in Korean. The presupposition-triggers of English and Korean can be confirmed to have almost similar parts because the basic ideas of people are similar. However, there are differences in terms of social, environmental, and cultural differences. In a situation where society becomes complicated, the study on presupposition will become more complicated. Especially, for young people who have developed and made SNS, the phenomenon will accelerate. The abbreviation, the internet term, and even the body language influence the presupposition-triggers.

Defects controlled hole doping and multivalley transport in SnSe single crystals

SnSe is a promising thermoelectric material with record-breaking figure of merit. However, to date a comprehensive understanding of the electronic structure and most critically, the self-hole-doping mechanism in SnSe is still absent. Here we report the highly anisotropic electronic structure of SnSe investigated by angle-resolved photoemission spectroscopy, in which a unique pudding-mould-shaped valence band with quasi-linear energy dispersion is revealed. We prove that p-type doping in SnSe is extrinsically controlled by local phase segregation of SnSe2 microdomains via interfacial charge transferring. The multivalley nature of the pudding-mould band is manifested in quantum transport by crystallographic axis-dependent weak localisation and exotic non-saturating negative magnetoresistance. Strikingly, quantum oscillations also reveal 3D Fermi surface with unusual interlayer coupling strength in p-SnSe, in which individual monolayers are interwoven by peculiar point dislocation defects. Our results suggest that defect engineering may provide versatile routes in improving the thermoelectric performance of the SnSe family.