bluuebunny/crossref_metadata_2025 huggingface dataset:
Linear Nearest Neighbor Realization of Quantum Circuits Using Clustering and Look-ahead Policy
Authors: Bhattacharjee Anirban , Bandyopadhyay Chandan , Mondal Bappaditya , Rahaman Hafizur
Published: July 2020

In the last couple of years, quantum computing has come out as emerging trends of computation not only due to its immense popularity but also for its commitment towards physical realization of quantum circuit in on-chip units. At the same time, the process of physical realization has faced several design constraints and one such problem is nearest neighbor (NN) enforcement which demands all the operating qubits to be placed adjacent in the implementable circuit. Though SWAP gate embedment can transform a design into NN architecture, it still creates overhead in the design. So, designing algorithms to restrict the use of SWAPs bears high importance.

Considering this fact, in this work, we are proposing a heuristic-based improved qubit placement strategy for efficient implementation of NN circuit. Two different design policies are being developed here. In the first scheme, a global reordering technique based on clustering approach is shown. In the second scheme, a local reordering technique based on look-ahead policy is developed. This look-ahead strategy considers the impact over the gates in the circuit and thereby estimates the effect using a cost metric to decide the suitable option for SWAP implementation. Furthermore, the joint use of both the ordering schemes also has been explored here. To ascertain the correctness of our design algorithms, we have tested them over a wide range of benchmarks and the obtained results are compared with some state-of-the-art design approaches. From this comparison, we have witnessed a considerable reduction on SWAP cost in our design scheme against the reported works’ results.
Extended Inverse Class-F Continuum for Designing Broadband Power Amplifier
Authors: Gan Decheng , Shi Weimin
Published: July 2020

The impedance space of the continuous inverse class-F power amplifier (PA) is extended in this paper. Traditionally, for extending impedance space, a reactive term is introduced into the current waveform of the continuous inverse class-F PA. In this paper, two reactive terms are introduced into the current and voltage waveforms simultaneously. The proposed method results in an expansive impedance space for designing broadband continuous inverse class-F PAs. For validating the proposed theory, a broadband PA working over 1.2–4.0[Formula: see text]GHz is designed and fabricated. Experimental results indicate that the fabricated broadband PA delivers a saturation power of 40.2–42.8[Formula: see text]dBm and a drain efficiency of 50.7–69%.
The hidden scalar Lagrangians within Horndeski theory
Authors: Horndeski Gregory W.
Published: July 2020

In this paper, I show that there exists a new way to obtain scalar–tensor field theories by combining a special scalar field on the cotangent bundle with a scalar field on spacetime. These two scalar fields act as a generating function for the metric tensor. When using these two scalar fields in the Horndeski Lagrangians, we discover, while seeking Friedmann–Lemaître–Robertson–Walker-type cosmological solutions, that hidden in the Horndeski Lagrangians are nondegenerate second-order scalar Lagrangians. In accordance with Ostrogradsky’s work, these hidden scalar Lagrangians lead to multiple vacuum solutions, and thereby predict the existence of the multiverse. The multiverse is comprised of numerous different types of individual universes. For example, some begin explosively, and then coast along exponentially forever at an accelerated rate, while others begin in that manner, and then stop expanding and contract.
Four metrics
Authors: Creutz Michael
Published: July 2020

A central idea in general relativity is that physics should not depend on the spacetime coordinates in use [A. Einstein, The Meaning of Relativity (Princeton University Press, 1945)]. But the qualitative description of various phenomena can appear superficially quite different. Here, we consider falling into a classical black hole using four distinct but equivalent metrics. First is the Schwarzschild case, with extreme time dilation at the horizon. Second, rescaling the dilation allows falling into the hole in finite proper time. Third, time and space are rescaled into a Penrose motivated picture where light trajectories all have unit slope. Fourth, a white hole variation of the second metric allows passage out through the horizon, with reentry forbidden.
Horizons 2020
Authors: Grumiller D. , Sheikh-Jabbari M. M. , Zwikel C.
Published: July 2020

Horizons of black holes or cosmologies are peculiar loci of spacetime, where interesting physical effects take place, some of which are probed by recent (EHT and LIGO) and future experiments (ET and LISA). We discuss that there are boundary degrees of freedom residing at the horizon. We describe their symmetries and their interactions with gravitational waves. This fits into a larger picture of boundary plus bulk degrees of freedom and their interactions in gauge theories. Existence and dynamics of the near horizon degrees of freedom could be crucial to address fundamental questions and apparent paradoxes in black holes physics.
Will gravitational waves discover the first extra-galactic planetary system?
Authors: Danielski Camilla , Tamanini Nicola
Published: July 2020

Gravitational waves have opened a new observational window through which some of the most exotic objects in the universe, as well as some of the secrets of gravitation itself, can now be revealed. Among all these new discoveries, we recently demonstrated15 that space-based gravitational wave observations will have the potential to detect a new population of massive circumbinary exoplanets everywhere inside our Galaxy. In this paper, we argue that these circumbinary planetary systems can also be detected outside the Milky Way, in particular within its satellite galaxies. Space-based gravitational wave observations might thus constitute the mean to detect the first extra-galactic planetary system, a target beyond the reach of standard electromagnetic searches.
Maximum force and naked singularities in higher dimensions
Authors: Barrow John D.
Published: July 2020

We discuss the existence of maximum forces in ([Formula: see text])-dimensional spacetimes and show that the existence of a mass-independent maximum force does not occur in general relativity in spaces of more than three dimensions. Instead, the maximum force increases with the masses of merging objects as [Formula: see text] and allows unbounded gravitational forces to occur. This suggests that naked singularities can arise in more than three dimensions because they are unprotected by a maximum force at the horizon surface. This creates a new perspective on the expectation of naked singularities in higher dimensions.
A path(-integral) toward non-perturbative effects in Hawking radiation
Authors: Chen Pisin , Sasaki Misao , Yeom Dong-han
Published: July 2020

Hawking’s seminal discovery of black hole evaporation was based on the semi-classical, perturbative method. Whether black hole evaporation may result in the loss of information remains undetermined. The solution to this paradox would most likely rely on the knowledge of the end-life of the evaporation, which evidently must be in the non-perturbative regime. Here we reinterpret the Hawking radiation as the tunneling of instantons, which is inherently non-perturbative. For definitiveness, we invoke the picture of shell–anti-shell pair production and show that it is equivalent to that of instanton tunneling. We find that such a shell pair production picture can help to elucidate firewalls and [Formula: see text] conjectures that attempt to solve the information paradox, and may be able to address the end-life issue toward an ultimate resolution.
EFFECT OF THE CALCINATION TEMPERATURE ON THE DIELECTRIC PROPERTIES OF 0.94NA0.5BI0.5TIO3–0.06BATIO3 CERAMICS
Authors: WU RUIFANG , DUAN RUIJIE , LIANG LINLIN , BIAN GANG , WANG JING
Published: July 2020

With the miniaturization of electronic products, the portability and the critical need of clean energy for environment have led to the development of lead-free electroceramics. In this work, lead-free dielectric ceramics of 0.94Na[Formula: see text]Bi[Formula: see text]TiO3–0.06BaTiO3 (NBT–0.06BT) are synthesized by wet solid-phase method. The effects of calcination temperature on phase structure, morphology, densification behavior and dielectric properties are investigated. The XRD results indicate that all samples demonstrate typical diffraction peaks of perovskite structure. The SEM and dielectric analytical results show that high-performance dielectric property of NBT–0.06BT ceramic with dense microstructure and appropriate grain size can be achieved when the calcination temperature is appropriate.
Evaluation and Modeling of Traffic Noise in Berhampur City, India
Authors: Sahu A. K. , Pradhan P. K. , Nayak S. K. , Pradhan M. , Mohanty C. R.
Published: July 2020

Traffic noise in urban areas is increasing day by day, owing to addition in the number of vehicles on road in developing and developed countries. The increase of noise level reduces the wellbeing of the exposed people. Exposure to high noise results in development of ill health including annoyance, high blood pressure, headache and other physiological and psychological problems. Noise not only affects the human life but also affects animals and birds in the ecosystem. In this experimental study, the evaluation of traffic noise in Berhampur city has been done. Eleven important locations covering the whole city were considered for traffic noise evaluation. Other than the evaluation of traffic noise, the well-known traffic noise prediction models have been tested here. It has been found that, in this situation, such established models do not function well and have a low coefficient of correlation value. A new befitting model has been formulated using multiple regression analysis to predict the traffic noise level and later on, it is also tested as well as validated at different locations.
Hopf algebras arising from partial (co)actions
Authors: Azevedo Danielle , Martini Grasiela , Paques Antonio , Silva Leonardo
Published: July 2020

In this paper, extending the idea presented by Takeuchi in [M. Takeuchi, Matched pairs of groups and bismash products of Hopf algebras, Comm. Algebra 9 (1981) 841–882.] and more generally by Majid in [S. Majid, Physics for algebraists: Non-commutative and non-cocommutative Hopf algebras by a bicrossproduct construction, J. Algebra 130(1) (1990) 17–64.], we introduce the notion of partial matched pair [Formula: see text] involving the concepts of partial action and partial coaction between two bialgebras [Formula: see text] and [Formula: see text]. Furthermore, we present sufficient conditions for the corresponding bismash product [Formula: see text] to generate a new Hopf algebra and, as illustration, a family of examples is provided. Moreover, under some hypotheses such sufficient conditions are also necessary conditions.
On the origin of the weak equivalence principle in a theory of emergent quantum mechanics
Authors: Gallego Torromé Ricardo
Published: July 2020

We argue that in a framework for emergent quantum mechanics, the weak equivalence principle is a consequence of concentration of measure in large-dimensional spaces of [Formula: see text]-Lipshitz functions. Furthermore, as a consequence of the emergent framework and the properties that we assume for the fundamental dynamics, it is argued that gravity must be a classical, emergent interaction.
On conjectures of Koike and Somos for modular identities for the Rogers–Ramanujan functions
Authors: Gugg Chadwick
Published: July 2020

In this paper, we prove modular identities conjectured by Koike and Somos for the Rogers–Ramanujan functions. Our methods focus on approaches that Ramanujan could have employed, including the theory of modular equations, dissections of identities, and methods derived from the approaches of Watson and Rogers.
The largest size of an (s,s + 1)-core partition with parts of the same parity
Authors: Nam Hayan , Yu Myungjun
Published: July 2020

Finding the largest size of a partition under certain restrictions has been an interesting subject to study. For example, it is proved by Olsson and Stanton that for two coprime integers [Formula: see text] and [Formula: see text], the largest size of an [Formula: see text]-core partition is [Formula: see text]. Xiong found a formula for the largest size of a [Formula: see text]-core partitions with distinct parts. In this paper, we find an explicit formula for the largest size of an [Formula: see text]-core partition such that all parts are odd (or even).
Restricted k-color partitions, II
Authors: Keith William J.
Published: July 2020

We consider [Formula: see text]-colored partitions, partitions in which [Formula: see text] colors exist but at most [Formula: see text] colors may be chosen per size of part. In particular these generalize overpartitions. Advancing previous work, we find new congruences, including in previously unexplored cases where [Formula: see text] and [Formula: see text] are not coprime, as well as some noncongruences. As a useful aside, we give the apparently new generating function for the number of partitions in the [Formula: see text] box with a given number of part sizes, and extend to multiple colors a conjecture of Dousse and Kim on unimodality in overpartitions.
Brauer groups and Néron class groups
Authors: González-Avilés Cristian D.
Published: July 2020

Let [Formula: see text] be a global field and let [Formula: see text] be a finite set of primes of [Formula: see text] containing the Archimedean primes. We generalize the duality theorem for the Néron [Formula: see text]-class group of an abelian variety [Formula: see text] over [Formula: see text] established previously by removing the requirement that the Tate–Shafarevich group of [Formula: see text] be finite. We also derive an exact sequence that relates the indicated group associated to the Jacobian variety of a proper, smooth and geometrically connected curve [Formula: see text] over [Formula: see text] to a certain finite subquotient of the Brauer group of [Formula: see text].
On norm relations for Asai–Flach classes
Authors: Grossi Giada
Published: July 2020

We give a new proof of the norm relations for the Asai–Flach Euler system built by Lei–Loeffler–Zerbes. More precisely, we redefine Asai–Flach classes in the language used by Loeffler–Skinner–Zerbes for Lemma–Eisenstein classes and prove both the vertical and the tame norm relations using local zeta integrals. These Euler system norm relations for the Asai representation attached to a Hilbert modular form over a quadratic real field [Formula: see text] have been already proved by Lei–Loeffler–Zerbes for primes which are inert in [Formula: see text] and for split primes satisfying some assumption; with this technique we are able to remove it and prove tame norm relations for all inert and split primes.
Quasimodularity of the kth residual cranks
Authors: Morrill Thomas , Simonič Aleksander
Published: July 2020

We study a family of residual crank generating functions defined on overpartitions, the so-called [Formula: see text]th residual cranks. Specifically, the moment generating functions associated to these cranks exhibit quasimodularity properties which are dependent on the choice of [Formula: see text]. We also show that the second moments of these cranks admit a combinatoric interpretation as weighted overpartition counts. This interpretation gives a refinement to an existing inequality between crank moments of differing modulus [Formula: see text].
Non-openness of v-adic Galois representation for A-motives
Authors: Frantzen Maike Ella Elisabeth
Published: July 2020

Drinfeld modules and A-motives s are the function field analogs of elliptic curves and abelian varieties. For both Drinfeld modules and [Formula: see text]-motives, one can construct their [Formula: see text]-adic Galois representations and ask whether the images are open. For Drinfeld modules, this question has been answered by Richard Pink and his co-authors; however, this question has not been addressed for [Formula: see text]-motives. Here, we clarify the rank-one case for A-motives and show that the image of Galois is open if and only if the virtual dimension is prime to the characteristic of the ground field.
The 2-adic analysis of Stirling numbers of the second kind via higher order Bernoulli numbers and polynomials
Authors: Adelberg Arnold
Published: July 2020

Several new estimates for the [Formula: see text]-adic valuations of Stirling numbers of the second kind are proved. These estimates, together with criteria for when they are sharp, lead to improvements in several known theorems and their proofs, as well as to new theorems, including a long-standing open conjecture by Lengyel. The estimates and criteria all depend on our previous analysis of powers of [Formula: see text] in the denominators of coefficients of higher order Bernoulli polynomials. The corresponding estimates for Stirling numbers of the first kind are also proved. Some attention is given to asymptotic cases, which will be further explored in subsequent publications.
Multidimensional Measurement of Electrical Coupling Properties of Nanostructured Substrates and Living Cells
Authors: Han Xueyan , Dong Litong , Cao Liang , Liu Chuanzhi , Zhang Wenxiao , Qu Kaige , Liu Ri , Yang Fan , Wang Zuobin
Published: July 2020

The study of the electrical coupling properties of living cells and materials plays an important role in tissue engineering and clinical applications. The electrical coupling between living cells and substrates directly affects the growth, secretion and death of cells, as well as the measurement accuracy of electrophysiological parameters. In this work, the point contact model of the electrical coupling of cells and substrates is studied. It was found that the sealing impedance and effective contact area were the most important parameters affecting the electrical coupling. Moreover, the structure of nano-scale groove was fabricated by direct laser interference patterning (DLIP), and cylindrical arrays were fabricated on resist films after exposed to electron beam lithography (EBL). The two nanostructures were used as the substrates in vitro culture. The electrical coupling properties between living cells and structural substrates were discussed subsequently. In addition, the impedance spectrum of living cells at various frequencies, the relationship between the living cell number and impedance, and the impedance of living cells at different growth periods were measured. Furthermore, the multidimensional impedance information of living cells was obtained, and the impedance deviations between the two structure arrays were analyzed to evaluate the electrical coupling properties between the living cells and substrates. The proposed multidimensional impedance analysis method provides a way for studying the electrical coupling properties of nano-structured substrates and living cells.
Equilibrium, Kinetic and Thermodynamic Studies for the Adsorption of Gemfibrozil onto Graphitized Carbon Black (GCB)
Authors: Liu Shicheng , Qi Guanjing , Ding Cong , Tan Kun , Yin Meiling , Zhang Tingting , Xu Zhenzhen
Published: July 2020

Adsorption of gemfibrozil (GF) from aqueous solution by highly/lowly graphitized carbon black (GCB-H/GCB-L) was investigated by batch and fixed-bed experiments. Results showed that the adsorption of GF onto GCB greatly depended on solution pH and graphitization of carbon. The pseudo-second-order kinetic model was found to be more appropriate in describing the adsorption processes of two GCBs. The adsorption equilibriums were well fitted with the Langmuir isotherm model, and GCB-H exhibited a higher adsorption capacity of 47.68 mg g−1at 298 K, compared with GCB-L of 4.33 mg g−1. GCB-H achieved 69.76% GF removals in simulated water after 6 h, indicating its potential practicability. The GCBs were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR), and the results indicated that the [Formula: see text]-[Formula: see text] interaction was strongly involved in the adsorption. Thermodynamic studies further suggested that the adsorption of GF on GCB-H was exothermic, which could happen spontaneously at any temperature mainly through [Formula: see text]-[Formula: see text] interaction for physical adsorption on the surface of the plane.
Coloring squares of graphs via vertex orderings
Authors: Yetim Mehmet Akif
Published: July 2020

We provide upper bounds on the chromatic number of the square of graphs, which have vertex ordering characterizations. We prove that [Formula: see text] is [Formula: see text]-colorable when [Formula: see text] is a cocomparability graph, [Formula: see text]-colorable when [Formula: see text] is a strongly orderable graph and [Formula: see text]-colorable when [Formula: see text] is a dually chordal graph, where [Formula: see text] is the maximum degree and [Formula: see text] = max[Formula: see text] is the multiplicity of the graph [Formula: see text]. This improves the currently known upper bounds on the chromatic number of squares of graphs from these classes.
Domination in signed graphs
Authors: Jeyalakshmi P.
Published: July 2020

Let [Formula: see text] be a graph. A signed graph is an ordered pair [Formula: see text] where [Formula: see text] is a graph called the underlying graph of [Formula: see text] and [Formula: see text] is a function called a signature or signing function. Motivated by the innovative paper of B. D. Acharya on domination in signed graphs, we consider another way of defining the concept of domination in signed graphs which looks more natural and has applications in social science. A subset [Formula: see text] of [Formula: see text] is called a dominating set of [Formula: see text] if [Formula: see text] for all [Formula: see text]. The domination number of [Formula: see text], denoted by [Formula: see text], is the minimum cardinality of a dominating set of [Formula: see text]. Also, a dominating set [Formula: see text] of [Formula: see text] with [Formula: see text] is called a [Formula: see text]-set of [Formula: see text]. In this paper, we initiate a study on this parameter.
Metric dimension of heptagonal circular ladder
Authors: Sharma Sunny Kumar , Bhat Vijay Kumar
Published: July 2020

Let [Formula: see text] be an undirected (i.e., all the edges are bidirectional), simple (i.e., no loops and multiple edges are allowed), and connected (i.e., between every pair of nodes, there exists a path) graph. Let [Formula: see text] denotes the number of edges in the shortest path or geodesic distance between two vertices [Formula: see text]. The metric dimension (or the location number) of some families of plane graphs have been obtained in [M. Imran, S. A. Bokhary and A. Q. Baig, Families of rotationally-symmetric plane graphs with constant metric dimension, Southeast Asian Bull. Math. 36 (2012) 663–675] and an open problem regarding these graphs was raised that: Characterize those families of plane graphs [Formula: see text] which are obtained from the graph [Formula: see text] by adding new edges in [Formula: see text] such that [Formula: see text] and [Formula: see text]. In this paper, by answering this problem, we characterize some families of plane graphs [Formula: see text], which possesses the radial symmetry and has a constant metric dimension. We also prove that some families of plane graphs which are obtained from the plane graphs, [Formula: see text] by the addition of new edges in [Formula: see text] have the same metric dimension and vertices set as [Formula: see text], and only 3 nodes appropriately selected are sufficient to resolve all the nodes of these families of plane graphs.
Linear programming approach for various domination parameters
Authors: Duraisamy Pandiaraja , Esakkimuthu Shanmugam
Published: July 2020

Domination is an emerging field in graph theory and many domination parameters were introduced in the meanwhile for different real time situations. Minimum domination number of a graph can be identified by converting the problem into linear programming problem (LPP). In this paper, LPP formulation for strong domination number, restrained domination number and strong restrained domination were developed. MATLAB program was coded to find the values of these parameters. The chain relations among these parameters are tried in four different types of network topologies. Simulation for these four parameters under four network topologies were conducted and it was noticed that in three network types, [Formula: see text] whereas, in the other one, [Formula: see text]. An improved upper bound for restrained domination number was approximated by using the probabilistic method.
The stability of independent transversal domination in trees
Authors: Roushini Leely Pushpam P. , Priya Bhanthavi K.
Published: July 2020

A set [Formula: see text] of vertices in a graph [Formula: see text] is called a dominating set if every vertex in [Formula: see text] is adjacent to a vertex in [Formula: see text]. An independent transversal dominating set in a graph [Formula: see text] is a dominating set which intersects every maximum independent set of [Formula: see text]. The minimum cardinality of an independent transversal dominating set is called the independent transversal domination number of [Formula: see text] denoted by [Formula: see text]. In this paper, we characterize those trees whose independent transversal domination number does not alter owing to the deletion of a vertex.
Defect elimination in green sand casting using simulation techniques: A case study
Authors: Singh Sarabjit , Sharma Neeraj , Khanna Rajesh
Published: July 2020

The Reynolds number of molten metal flowing mold cavity causes bulk turbulence and is the main cause of defects like shrinkage porosity and sand erosion. Machined housings with shrinkage porosity at critical bearing bores and surface made the casting useless. In old gating casting areas of perimeters 290[Formula: see text]mm and 264[Formula: see text]mm of transmission housing, Reynolds numbers were observed as 16307 and 13806, respectively using simulation software. Data were collected from experiments to change casting area perimeters from 785[Formula: see text]mm and 785[Formula: see text]mm along with the addition of overlap area. New Reynolds numbers at two locations were observed as 3705 and 3393, respectively. Molten metal pressure, velocity and temperature results were related for final shrinkage results of the components on full production. The purpose of the study is to reduce shrinkage and porosity defects in green sand casting part using MAGMAS simulation software. High outcome was the reduction of casting machining rejection in transmission housing casting from 5.8% 0.7% with savings of approximately 0.13 million USD over the period of 14 months. Implications of this work include casting defects study and reduction in different grades and weight range.
ToxoplasmaMechanisms for Delivery of Proteins and Uptake of Nutrients Across the Host-Pathogen Interface
Authors: Wang Yifan , Sangaré Lamba Omar , Paredes-Santos Tatiana C. , Saeij Jeroen P. J.
Published: July 2020

Many intracellular pathogens, including the protozoan parasite Toxoplasma gondii, live inside a vacuole that resides in the host cytosol. Vacuolar residence provides these pathogens with a defined niche for replication and protection from detection by host cytosolic pattern recognition receptors. However, the limiting membrane of the vacuole, which constitutes the host-pathogen interface, is also a barrier for pathogen effectors to reach the host cytosol and for the acquisition of host-derived nutrients. This review provides an update on the specialized secretion and trafficking systems used by Toxoplasma to overcome the barrier of the parasitophorous vacuole membrane and thereby allow the delivery of proteins into the host cell and the acquisition of host-derived nutrients.
A Bacterial Tower of Babel: Quorum-Sensing Signaling Diversity and Its Evolution
Authors: Aframian Nitzan , Eldar Avigdor
Published: July 2020

Quorum sensing is a process in which bacteria secrete and sense a diffusible molecule, thereby enabling bacterial groups to coordinate their behavior in a density-dependent manner. Quorum sensing has evolved multiple times independently, utilizing different molecular pathways and signaling molecules. A common theme among many quorum-sensing families is their wide range of signaling diversity—different variants within a family code for different signal molecules with a cognate receptor specific to each variant. This pattern of vast allelic polymorphism raises several questions—How do different signaling variants interact with one another? How is this diversity maintained? And how did it come to exist in the first place? Here we argue that social interactions between signaling variants can explain the emergence and persistence of signaling diversity throughout evolution. Finally, we extend the discussion to include cases where multiple diverse systems work in concert in a single bacterium.
Polymorphic Toxins and Their Immunity Proteins: Diversity, Evolution, and Mechanisms of Delivery
Authors: Ruhe Zachary C. , Low David A. , Hayes Christopher S.
Published: July 2020

All bacteria must compete for growth niches and other limited environmental resources. These existential battles are waged at several levels, but one common strategy entails the transfer of growth-inhibitory protein toxins between competing cells. These antibacterial effectors are invariably encoded with immunity proteins that protect cells from intoxication by neighboring siblings. Several effector classes have been described, each designed to breach the cell envelope of target bacteria. Although effector architectures and export pathways tend to be clade specific, phylogenetically distant species often deploy closely related toxin domains. Thus, diverse competition systems are linked through a common reservoir of toxin-immunity pairs that is shared via horizontal gene transfer. These toxin-immunity protein pairs are extraordinarily diverse in sequence, and this polymorphism underpins an important mechanism of self/nonself discrimination in bacteria. This review focuses on the structures, functions, and delivery mechanisms of polymorphic toxin effectors that mediate bacterial competition.
From Birth and Throughout Life: Fungal Microbiota in Nutrition and Metabolic Health
Authors: Fiers William D. , Leonardi Irina , Iliev Iliyan D.
Published: July 2020

The human gastrointestinal tract is home to a vibrant, diverse ecosystem of prokaryotic and eukaryotic microorganisms. The gut fungi (mycobiota) have recently risen to prominence due to their ability to modulate host immunity. Colonization of the gut occurs through a combination of vertical transmission from the maternal mycobiota and environmental and dietary exposure. Data from human and animal studies demonstrate that nutrition strongly affects the mycobiota composition and that changes in the fungal communities can aggravate metabolic diseases. The mechanisms pertaining to the mycobiota's influence on host health, pathology, and resident gastrointestinal communities through intrakingdom, transkingdom, and immune cross talk are beginning to come into focus, setting the stage for a new chapter in microbiota–host interactions. Herein, we examine the inception, maturation, and dietary modulation of gastrointestinal and nutritional fungal communities and inspect their impact on metabolic diseases in humans.
On the Minimum Variable Connectivity Index of Unicyclic Graphs with a Given Order
Authors: Yousaf Shamaila , Bhatti Akhlaq Ahmad , Ali Akbar
Published: July 2020

The variable connectivity index, introduced by the chemist Milan Randić in the first quarter of 1990s, for a graph G is defined as ∑vw∈EGdv+γdw+γ−1/2, where γ is a non-negative real number and dw is the degree of a vertex w in G. We call this index as the variable Randić index and denote it by Rvγ. In this paper, we show that the graph created from the star graph of order n by adding an edge has the minimum Rvγ value among all unicyclic graphs of a fixed order n, for every n≥4 and γ≥0.
Comparison of First- and Second-Generation Drug-Eluting Stents in Patients with Acute Myocardial Infarction and Prediabetes Based on the Hemoglobin A1c Level
Authors: Kim Yong Hoon , Her Ae-Young , Jeong Myung Ho , Kim Byeong-Keuk , Hong Sung-Jin , Kim Seunghwan , Ahn Chul-Min , Kim Jung-Sun , Ko Young-Guk , Choi Donghoon , Hong Myeong-Ki , Jang Yangsoo
Published: July 2020

Objective. To compare major clinical outcomes after successful percutaneous coronary intervention (PCI) with first-generation (1G) drug-eluting stents (DES) and second-generation (2G) DES in patients with acute myocardial infarction (AMI) and prediabetes. Background. Patients with prediabetes are associated with an increased incidence of coronary artery disease. The relative superiority of 1G- and 2G-DES in these patients is not well established. Methods. A total of 4997 patients with AMI and prediabetes were divided into two groups: the 1D-DES group (n = 726) and the 2G-DES group (n = 4271). The primary outcomes were the patient-oriented composite outcomes (POCOs) defined as all-cause death, recurrent myocardial infarction (Re-MI), and any disease revascularization at 2-year follow-up. The secondary outcome was probable or definite stent thrombosis (ST). Results. After propensity score-matching (PSM) analysis, two PSM groups (698 pairs, n = 1396, C-statistics = 0.725) were generated. The cumulative incidence rates of POCOs (hazard ratio (HR): 1.467; 95% confidence interval (CI): 1.068–2.015; p=0.018), any disease revascularization (HR: 2.259; 95% CI: 1.397–3.654; p=0.001), and ST (HR: 4.361; 95% CI: 1.243–15.30; p=0.021) in the 1G-DES group were significantly higher than those in the 2G-DES group. However, the cumulative incidence rates of all-cause death, cardiac death, and Re-MI were similar between the two groups. Conclusions. In patients with AMI and prediabetes, 2G-DES implantation was more efficacious than 1G-DES implantation over a 2-year follow-up period. However, further studies are needed to confirm these results.
Research on Innovation Efficiency of Listed Companies in Development Zone Based on the Three-Stage DEA-Tobit Model: A Case Study of Hubei Province
Authors: Xu Peng , Luo Fan , Zhang Ziyue , Xu Hongyi
Published: July 2020

This study applies 3-stage data envelopment (DEA) of 24 listed companies in the development zone of Hubei Province from 2012 to 2017 based on the panel data; we used the DEA-Tobit model and regression analysis method on the sample in order to measure the factors affecting the innovation efficiency of listed companies and the efficiency of corporate innovation. The results demonstrated that the innovation efficiency of listed companies in the development zone of Hubei Province is relatively low. It is necessary to improve the innovation system of the development zone and give the full initiative to the role of corporate innovation as a mainstay. The four environmental variables of the number of enterprises, government subsidies, foreign direct investment in the development zone, and fixed asset investment have a significant impact on innovation efficiency. The enterprise size, operating capacity, and state-owned shares of the company have a significant positive impact on the innovation efficiency. But the number of years of the establishment has a significant negative impact on innovation efficiency. Moreover, the quality of the workers is not significant. Therefore, we must increase government investment in innovation to expand the scale of listed companies in the development zone, improve the environment for foreign investment, further strengthen the construction of talented people of companies, and enhance the original ability of innovation.
Tumor Regression Grade Predicts Survival in Locally Advanced Gastric Adenocarcinoma Patients with Lymph Node Metastasis
Authors: Tong Yilin , Zhu Yanmei , Zhao Yan , Shan Zexing , Zhang Jianjun , Liu Dong
Published: July 2020

Background. Tumor regression grade (TRG) is widely used in gastrointestinal carcinoma to evaluate pathological responses to neoadjuvant chemotherapy (NCT), but whether it is an independent prognostic factor is still controversial. The aim of this study is to investigate the value of TRG in locally advanced gastric adenocarcinoma patients who underwent NCT and curative resection. Methods. Pathological regression was reevaluated according to the Mandard TRG. Survival curves were obtained by the Kaplan–Meier method, and differences in overall survival (OS) and disease-free survival (DFS) were compared using the log-rank test. Univariate and multivariate analyses for survival were based on the Cox proportional hazards method. Results. In total, 290 patients were identified in our electronic database. In univariable analysis, TRG was associated with OS (HR=3.822, P≤0.001) and DFS (HR=3.374, P≤0.001). However, in multivariable analysis, TRG was not an independent factor for OS (P=0.231) or DFS (P=0.191). In the stratified analysis, TRG retrieved prognostic significance in patients with the metastasis of lymph node (HR=2.034, P=0.035 for OS; HR=2.220, P=0.016 for DFS), while not in patients with negative lymph node (P=0.296 for OS; P=0.172 for DFS). Conclusions. TRG was not an independent predictor for survival, but the system regained its predicting significance in patients with lymph node metastasis.
Genotype Distribution of CNDP1 Polymorphisms in the Healthy Chinese Han Population: Association with HbA1c and Fasting Blood Glucose
Authors: Zhang Shiqi , Xu Juan , Cui Di , Jiang Shujuan , Xu Xin , Zhang Yi , Zhu Dongchun , Xia Li , Yard Benito , Wu Yonggui , Zhang Qiu
Published: July 2020

We have previously reported that the CNDP1 (CTG)5 allele affords protection against diabetic nephropathy (DN) in patients with Type 2 diabetes (T2DM) of Caucasian origin. Because the incidence of ESRD attributable to both Type 1 diabetes (T1DM) and T2DM is higher among South Asian than Caucasian people, the present study assessed relevant CNDP1 polymorphisms and their association with metabolic parameters in the Chinese Han population. To this end, the (CTG)n allele distribution along with 5 relevant SNPs in the CNDP1 gene, previously reported to be associated with DN in non (CTG)5 carriers of Afro-American ethnicity, were determined in 663 healthy individuals. The (CTG)6 homozygous genotype was the most prevalent (84.5%) genotype in the Chinese Han population. The (CTG)5 and (CTG)4 alleles were present in a small minority of individuals accounting for 15.2% and 0.3% of genotypes with at least one (CTG)5 or one (CTG)4 allele, respectively. Only 0.5% of individuals carried the homozygous (CTG)5 genotype and individuals carrying the homozygous (CTG)4 genotype were not found. The minor allele frequencies (MAFs) of the 5 SNP were 0.197 (C allele for rs4892247), 0.0855 (C allele for rs62099905), 0.085 (G allele for rs62099906), 0.066 (T allele for rs62099907), and 0.18 (A allele for rs72979715). All the SNPs except rs4892247 genotypes were in the Hardy-Weinberg equilibrium. Neither the (CTG)n polymorphism nor the latter three SNPs reached significance when compared with different metabolic parameters. In contrast, individuals with the TT genotype of rs62099905 presented lower fasting blood glucose but higher HbA1c levels. In conclusion, the rs62099905 in the CNDP1 gene is associated with serum glucose levels in the healthy Chinese Han population, while for the CNDP1 (CTG)n polymorphism, no association with serological parameters was found.
Continuum Robots for Manipulation Applications: A Survey
Authors: Kolachalama Srikanth , Lakshmanan Sridhar
Published: July 2020

This paper presents a literature survey documenting the evolution of continuum robots over the past two decades (1999–present). Attention is paid to bioinspired soft robots with respect to the following three design parameters: structure, materials, and actuation. Using this three-faced prism, we identify the uniqueness and novelty of robots that have hitherto not been publicly disclosed. The motivation for this study comes from the fact that continuum soft robots can make inroads in industrial manufacturing, and their adoption will be accelerated if their key advantages over counterparts with rigid links are clear. Four different taxonomies of continuum robots are included in this study, enabling researchers to quickly identify robots of relevance to their studies. The kinematics and dynamics of these robots are not covered, nor is their application in surgical manipulation.
Relationship between Pain Behavior and Changes in KCNA2 Expression in the Dorsal Root Ganglia of Rats with Osteoarthritis
Authors: Zhao Qihong , Fan Lei , Wang Jiafeng , Deng Xiaoming
Published: July 2020

Objective. To investigate the relationship between pain behavior and potassium voltage-gated channel subfamily A member 2 (KCNA2) expression in dorsal root ganglia (DRGs) of rats with osteoarthritis (OA). Methods. Male Sprague-Dawley rats were randomly divided into three groups: blank control group (group C), normal saline group (group S), and group OA. Paw withdrawal mechanical threshold (PWMT) and paw withdrawal thermal latency (PWTL) were measured one day before injection and one, two, four, and six weeks after injection. At one, two, four, and six weeks after injection, pathological knee joint changes and activated transcription factor-3 (ATF-3) and KCNA2 expressions in DRGs were analyzed. Results. Compared with preinjection, PWMT and PWTL at two, four, and six weeks after injection were significantly decreased in the group OA (P<0.05 or 0.01). Compared with group C, PWMT and PWTL at two, four, and six weeks after injection were significantly decreased in the group OA (P<0.05 or 0.01). In the group OA, slight local articular cartilage surface destruction was found at week one. The cartilage surface destruction gradually developed, and the exacerbation of cartilage matrix reduction and bone hyperplasia were increasingly aggravated and eventually evolved into advanced OA in the second to sixth weeks. Compared with group C, ATF-3 expression was significantly increased, and KCNA2 expression was significantly decreased in the group OA at two, four, and six weeks after injection (P<0.05 or 0.01). Compared to baseline, ATF-3 expression was significantly increased, and KCNA2 expression was significantly decreased in the group OA (P<0.05 or 0.01). Conclusion. Pain behavior in OA rats was associated with decreased KCNA2 expression in DRGs.
Tumor Volume Kinetic Analyses Might Explain Excellent Prognoses in Young Patients with Papillary Thyroid Carcinoma
Authors: Kasahara Toshihiko , Miyauchi Akira , Ito Yasuhiro , Kudo Takumi , Masuoka Hiroo , Higashiyama Takuya , Ito Mitsuru , Kihara Minoru , Miya Akihiro
Published: July 2020

Introduction. Young patients with papillary thyroid carcinoma (PTC) generally have excellent prognoses despite their often-advanced disease status. The reasons for this excellent prognosis are poorly understood. Objective. To investigate the natural history of PTC in young patients, we compared the observed tumor volume-doubling rate (TV-DR) with the hypothetical tumor volume-doubling rate (hTV-DR) before presentation in young PTC patients. DR is an inverse of the doubling time and indicates the number of doublings that occur in a unit of time. A negative value indicates the number of times the volume is reduced by half per unit time. Methods. We enrolled 20 patients with the following characteristics: age ≤19 years, diagnosed with PTC according to the cytology results between 2013 and 2018 and followed-up with periodical ultrasound examinations for ≥3 months before surgery for various reasons. Seventeen patients later underwent surgery confirming the diagnosis. We calculated TV-DRs using serial measurements of tumor diameters after presentation and hTV-DRs using tumor diameters and patients’ age at presentation, assuming that a single cancer cell was present at the patient’s birth and that the tumor grew at a constant rate. These values indicate the lowest growth rates necessary for a single cancer cell to achieve the full tumor size at presentation. Results. Thirteen patients had positive TV-DRs (/year) ranging from 0.09 to 1.89, indicating tumor growth, and the remaining seven patients had negative values (−0.08 to −1.21), indicating regression. The median TV-DR was 0.29. The hTV-DRs (1.48–2.66, median 1.71) were significantly larger than the TV-DRs (p<0.001), indicating much faster growth before presentation. Conclusions. These data suggest that deceleration of tumor growth had already occurred at presentation in the majority of the cases. This might explain why disease-specific survival is excellent despite frequent findings of advanced disease in young patients with PTC.
Prevalence of Extended-Spectrum β-Lactamases in E. coli of Rats in the Region North East of Gabon
Authors: Onanga Richard , Mbehang Nguema Pierre Philippe , Ndong Atome Guy Roger , Mabika Mabika Arsène , Ngoubangoye Berthelemy , Komba Tonda Wed Leslie , Obague Mbeang Jean Constant , Lebibi Jacques
Published: July 2020

Antibiotic resistance occurs in the environment by multiplication and the spread of multidrug-resistant bacteria that would be due to an improper and incorrect use of antibiotics in human and veterinary medicine. The aim of this study was to establish the prevalence of E.coli producing Extended-Spectrum beta-Lactamase (ESBL) antibiotics from rats and gregarious animals in a semirural area of Gabon and to evaluate the origin of a resistance distribution in the environment from animal feces. The bacterial culture was carried out, and the identification of E. coli strains on a specific medium and the antibiotic susceptibility tests allowed establishing the prevalence. Characterization of resistance genes was performed by gene amplification after DNA extraction. On 161 feces collected in rats, 32 strains were isolated, and 11 strains of E. coli produced ESBL with a prevalence of 34.37%. Molecular tests showed that CTX-M genes 214 bp were identified in rats. The presence of CTX-M genes could have a human origin. So, the rats can carry ESBL-producing Enterobacteriaceae which poses a risk to human health and pets in this region of Gabon.
A Case of Cerebral Granuloma and Optic Papillitis due to Brucella sp.
Authors: Chiappe-Gonzalez A. , Solano-Loza A
Published: July 2020

We document a case of a 24-year-old woman who presented with cerebral granuloma and optic papillitis associated to Brucella sp. infection, whose diagnosis was made with a brain biopsy and serology tests, with clinical improvement following specific antibiotic therapy. The patient was followed up for over a year without evidence of relapse.
Is 18F-FDG PET/CT an Accurate Way to Detect Lymph Node Metastasis in Colorectal Cancer: A Systematic Review and Meta-Analysis
Authors: Dahmarde Hamid , Parooie Fateme , Salarzaei Morteza
Published: July 2020

Aims. The purpose of this study was to assess the diagnostic value of 18F-fluorodeoxy-glucose positron emission tomography/computed tomography (FDG PET/CT) for detection of lymph node (LN) metastasis of colorectal cancer. Material and Methods. A computerized search was performed to determine the relevant articles, published before October 2019. Stata Statistical Software, version 15.0, and Meta-Disc (version 1.4) were used for the meta-analysis. Results. the sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio were 0.65, 0.75, 4.57, and 0.37 respectively. Studies that used SUVmax cut-off value (≤2.5) demonstrated the best accuracy. Conclusion. 18F-FDG PET/CT shows a low sensitivity and high specificity for detecting the metastasis of LNs in patients with newly diagnosed colorectal cancer.