Mutual Position Research Articles

Derivatives of cyclam-1,8-diacetic acid: Synthesis and complexes with divalent transition metal ions

1,4,8,11-tetraazacyclotetradecane-1,8-diacetatic acid, H2te2a, and series of its derivative bearing two substituted N-benzyl groups were synthesized and their complexes were studied. Series of CoII and ZnII complexes was prepared in the solid-state and X-ray diffraction analysis showed that the metal ions are hexacoordinated by four nitrogen atoms of the macrocycle and two oxygen atoms of the carboxylate pendants. The two oxygen atoms were in cis and trans mutual position in the CoII and ZnII complexes, respectively. Potentiometric study of CoII, ZnII, CuII and NiII-H2te2a systems showed that the complexes are highly thermodynamically stable and the ligand is selective for CuII ions (logK = 27.5) over the other ions (logK = 21–22). UV-VIS and electrochemical data for the CoII-H2te2a system showed that complexation was rather slow (several hours at pH 4.5, 25 °C) and the complex undergoes slow oxidation with air oxygen.

Astronomically controlled deep-sea life in the Late Cretaceous reconstructed from ultra-high-resolution inoceramid shell archives.

The periodicity of the mutual position of celestial bodies in the Earth-Moon-Sun system is crucial to the functioning of life on Earth. Biological rhythms affect most of the processes inside organisms, and some can be recorded in skeletal remains, allowing one to reconstruct the cycles that occur in nature deep in time. In the present study, we have used ultra-high-resolution elemental ratio scans of Mg/Ca, Sr/Ca and Mn/Ca from the fossil, ca. 70 Ma old inoceramid bivalve Inoceramus (Platyceramus) salisburgensis from deep aphotic water and identified a clear regularity of repetition of the geochemical signal every of ~0.006 mm. We estimate that the shell accretion rate is on average ~0.4cm of shell thickness per lunar year. Visible light-dark lamination, interpreted as a seasonal signal corresponding to the semilunar-related cycle, gives a rough shell age estimate and growth rate for this large bivalve species supported by a dual feeding strategy. We recognize a biological clock that follows either a semilunar (model A) or a tidal (model B) cycle. This cycle of tidal dominance seems to fit better considering the biological behaviour of I. (P.) salisburgensis, including the estimated age and growth rate of the studied specimens. We interpret that the major control in such deep-sea environment, well below the photic zone and storm wave base, was due to barotropic tidal forces, thus changing the water pressure.

Investigating the Origin and Evolution of Polyploid Trifolium medium L. Karyotype by Comparative Cytogenomic Methods.

Trifolium medium L. is a wild polyploid relative of the agriculturally important red clover that possesses traits promising for breeding purposes. To date, T. medium also remains the only clover species with which agriculturally important red clover has successfully been hybridized. Even though allopolyploid origin has previously been suggested, little has in fact been known about the T. medium karyotype and its origin. We researched T. medium and related karyotypes using comparative cytogenomic methods, such as fluorescent in situ hybridization (FISH) and RepeatExplorer cluster analysis. The results indicate an exceptional karyotype diversity regarding numbers and mutual positions of 5S and 26S rDNA loci and centromeric repeats in populations of T. medium ecotypes and varieties. The observed variability among T. medium ecotypes and varieties suggests current karyotype instability that can be attributed to ever-ongoing battle between satellite DNA together with genomic changes and rearrangements enhanced by post-hybridization events. Comparative cytogenomic analyses of a T. medium hexaploid variety and diploid relatives revealed stable karyotypes with a possible case of chromosomal rearrangement. Moreover, the results provided evidence of T. medium having autopolyploid origin.

Analytical Modeling of Rotary Electromagnetic Fault Current Limiter

Rotary electromagnetic fault current limiter (FCL) is an emerging technology for limiting fault currents in the power network. The device consists of two movable air-core spherical reactor rings (i.e., inner and outer rings). The movable feature allows the reactor rings to rotate, and form a proper mutual positional displacement. This can limit the fault current since the effective inductance of the device is dependent to the mutual angular position of the reactor rings. Due to the unconventional structure, to this date, the design process has solely been based on finite element (FE) method. This paper aims to analytically validate the theory and the overall functionality of the device in both the steady state and transient regime. For this propose, the resistance and the inductance of the device are first computed at normal operating condition using the basic theory of engineering electromagnetics. Next, performance characteristics such as electromagnetic torque, rotational displacement of the reactors, effective inductance of the device, and the network current are calculated at the faulty condition. For verification purposes, analytical results are compared with via FE simulation and experimental test.

Spatial geometrical calibration of optoelectronic devices

Space equipment experiences high thermal and mechanical loads that cause deformation of its structures, as well as elements of optical systems and radiation receivers, which can lead to changes in the mutual position of the optoelectronic device elements, disturbing its alignment, degrading image quality and increasing pointing errors. This paper presents a method of spatial geometric calibration that does not require additional equipment and investigates the dependence of the identification results on the viewing angle. The proposed methodology of optoelectronic instrument calibration is intended to improve efficiency, reliability and survivability of automated spacecrafts during their operation.

Intraprocedural computed tomography-guided navigation with ventilatory strategy for atelectasis (ICNVA): a modified electromagnetic navigation bronchoscopy.

Computed tomography (CT)-body divergence limits the accuracy of electromagnetic navigation bronchoscopy (ENB) in peripheral lung lesions diagnosis. We developed intraprocedural CT-guided navigation with ventilatory strategy for atelectasis (ICNVA) ENB for patients with peripheral lung lesions. Retrospective observational study in which ten consecutive patients with pulmonary lesions (without bronchial direct connection) underwent ICNVA-ENB was conducted. During ICNVA-ENB, intraoperative CT data were used for ENB path planning, and a new ventilation strategy were employed to help maintain the pulmonary region in a static and inflation state which reduce CT to body divergence. We collected three sets of CT data: preENB CT, post-anesthesia intubation CT, and postENB CT. To evaluate the accuracy of ICNVA-ENB, we measured the distance between the ENB probe and the actual lesion location, but also recorded the results of rapid on-site evaluation (ROSE), and postoperative pathology. To evaluate the impact of CT-body divergence induced by atelectasis, we calculated the mutual position distance of target lesions in preENB CT, post-anesthesia intubation CT and postENB CT. Furthermore, ENB operation time and operative complications were recorded. Our analysis revealed that the distance between the navigation probe with the actual location of lesion center was 4-10 (5.90±1.73) mm. The ROSE results were consistent with the postoperative pathological diagnosis in 9 out of 10 patients (90%). The ICNVA-ENB atelectasis CT-body divergence was smaller than traditional ENB (12.10±3.67 vs. 6.60±2.59 mm, P<0.01). The ENB operation time was 20-53 (29.30±10.14) minutes and one patient developed slight intrapulmonary hemorrhage. ICNVA-ENB can reduce the CT-body divergence and appears to be safe and accurate for patients with peripheral lung lesions.

Some exact solutions that describe an ideal fluid flow with a free boundary

The study is aimed at constructing exact solutions that describe unsteady flows of an ideal fluid with a free boundary. Currently existing examples of solutions of this kind have a linear or quadratic initial field of velocities. The object of the present study is flows with a cubic initial velocity field. Several exact solutions are obtained by using a method based on the complex Hopf equation for the complex velocity. One of the main problems in solving the Euler equations in the domain with a free boundary is to study the positions of singular points because these points can reach the free boundary with time, which may lead to solution destruction. In the present case, singularities can be found explicitly. However, as the initial velocity field is defined by a third-power polynomial, one has to study the Riemann surfaces for the function of complex velocity in order to determine the mutual positions of the singularities and flow domain. It is shown that any initial velocity field defined by a cubic polynomial yields one of seven flows described in the paper with time. It is of interest that there are examples of flows that exist for a finite time and break down when the singularities reach the free boundary. Using a certain modification of the Hopf equation, we obtain a two-parameter family of exact solutions that describe fluid flows with a free boundary. Two examples of this family are considered. In one of them, the solution breaks down within a finite time. The second example is of interest because the motion of a singular point in the fluid leads to the formation of a narrow channel with free boundaries.

Effect of 3D Shape of Pump-Turbine Runner Blade on Flow Characteristics in Turbine Mode

The effect of blade spatial profiling with the help of tangential blade lean of Francis pump-turbine runner with heads up to 200 m on the flow structure and energy characteristics was numerically investigated. A flow part model of Francis pump-turbine of the Dniester pumped storage plant was adopted as original version. Two new blade systems were designed, which differed from the original version by mutual position of cross-sections in tangential direction: with positive and negative lean, while the shape of the cross-sections themselves remained unchanged. Modeling of the viscous incompressible flow in calculation domain, which contains one channel of the guide vane and the runner, for three variants of flow parts, was performed using the IPMFlow software based on numerical integration of the Reynolds equations with an additional term containing artificial compressibility. To take into account the turbulent effects, the SST differential two-parameter turbulence model of Menter is applied. Numerical integration of the equations is carried out using an implicit quasi-monotonic Godunov scheme of second order accuracy in space and time. The study was carried out for models with runner diameter of 350 mm in a wide range of guide vane openings at reduced rotation frequencies corresponding to the minimal, design and maximal heads of the station. A comparison of pressure fields and velocity vectors in the runners, pressure graphs on runner blades, distribution of velocity components at inlet to a draft tube, and efficiency of three variants of flow parts are presented. It was concluded that calculation domain with the new RK5217M2 runner with negative tangential lean has the best characteristics. An experimental study of three runners on a hydrodynamic stand are planned

Calculation of centralities in protein kinase A

Topological analysis of protein residue networks (PRNs) is a common method that can help to understand the roles of individual residues. Here, we used protein kinase A as a study object and asked what already known functionally important residues can be detected by network analysis. Along several traditional approaches to weight edges in PRNs we used local spatial pattern (LSP) alignment that assigns high weights to edges only if CαCβ vectors for the corresponding residues retain their mutual positions and orientation. Our results show that even short molecular dynamic simulations of 10 to 20 ns can give convergent values for betweenness and degree centralities calculated from the LSP-based PRNs. Using these centralities, we were able to clearly distinguish a group of residues that are highly conserved in protein kinases and play important functional and regulatory roles. In comparison, traditional methods based on cross-correlation and linear mutual information were much less efficient for this particular task. These results call for reevaluation of the current methods to generate PRNs.

Fourth moments of the code-weights

In this paper we give the fourth joint moments of the weights of random linear codes. We calculate the fourth moment using mutual position of 4 lines. The solution of the 4-subspace problem is known and we obtain the information on line configurations from the set of indecomposables of the 4-subspace problem.

Metahouse: Noise‐Insulating Chamber Based on Periodic Structures

AbstractNoise pollution remains a challenging problem requiring the development of novel systems for noise insulation. Extensive work in the field of acoustic metamaterials has led to various ventilated structures which, however, are usually demonstrated for rather narrow regions of the audible spectrum. In this work, the idea of metamaterial‐based systems is further extended, developing the concept of a metahouse chamber representing a ventilated structure for multiple band noise insulation. Broad stop‐bands originate from strong coupling between pairs of Helmholtz resonators constituting the structure. The averaged transmission −18.6 dB are demonstrated numerically and experimentally within the spectral range from 1500 to 16 500 Hz. The sparseness of the structure together with the possibility to use optically transparent materials suggest that the chamber may be also characterized by partial optical transparency depending on the mutual position of structural elements. The obtained results are promising for development of novel noise‐insulating structures advancing urban science.

Whispering gallery modes of a triatomic photonic molecule

In this paper, we present the results of numerical simulations of the optical spectra of a three-sphere photonic molecule. The configuration of the system was continuously modified from linear to triangular, in-plane with the fundamental mode excited in one of the spheres and perpendicular to it. We found the relative insensitivity of the spectra to the in-plane deviation from the linear arrangement up to about 110°. For larger angles, the spectra show significant modification consisting of the major spectral peaks splitting and shifting. On the contrary, the spectra are quite sensitive to out-of-plane molecule deviation, even at small angles. Thus, the spectra of photonic molecules can be modified by changing the mutual positions of the constituent resonators, which can be useful in reconfigurable photonic devices.

Distributed Collaborative Pedestrian Inertial SLAM With Unknown Initial Relative Poses

Collaborative indoor positioning techniques for pedestrians have been extensively researched in the past years, particularly concerning the range-based collaborative indoor positioning system. However, range-based indoor collaboration methods suffer from nonline-of-sight (NLOS) and electromagnetic signal loss in indoor environments. Meanwhile, these methods require prior knowledge of the initial relative pose of the pedestrian, which is difficult to obtain in such an environment. To overcome the unreliable mutual observation and the lack of initial relative poses information in collaborative position systems, this article proposes a distributed collaborative inertial simultaneous localization and mapping (DCOGI-SLAM) framework for collaborative pedestrian positioning systems in unknown indoor environments without prior information. A coarse alignment method of relative poses based on encounter events is proposed to obtain the initial relative poses of pedestrians. A mutual position observation is constructed based on the map constructed through the occupancy grid-based inertial SLAM (OGI-SLAM) method to provide a stable innovation for collaborative correction of positioning errors, insulating the system from the NLOS and the loss of ranging signals. Moreover, a distributed collaborative occupancy grid-based inertial simultaneous localization and mapping (DCOGI-SLAM) framework is proposed to enable each pedestrian positioning system in a formation to operate independently. In a two-person collaborative experiment over a space of approximately 2500 m2, the proposed system can obtain comparable accuracy to single OGI-SLAM with known initial relative position information, when the initial relative position information is unknown. The average positioning error of the proposed method is 1.48 m.

Sterically and Electronically Flexible Pyridylidene Amine Dinitrogen Ligands at Palladium: Hemilabile cis/trans Coordination and Application in Dehydrogenation Catalysis.

Ligand design is crucial for the development of new catalysts and materials with new properties. Herein, the synthesis and unique hemilabile coordination properties of new bis-pyridylidene amine (bis-PYE) ligands to palladium, and preliminary catalytic activity of these complexes in formic acid dehydrogenation are described. The synthetic pathway to form cationic complexes [Pd(bis-PYE)Cl(L)]X with a cis-coordinated N,N-bidentate bis-PYE ligand is flexible and provides access to a diversity of PdII complexes with different ancillary ligands (L=pyridine, DMAP, PPh3 , Cl, P(OMe)3 ). The 1 H NMR chemical shift of the trans-positioned PYE N-CH3 unit is identified as a convenient and diagnostic handle to probe the donor properties of these ancillary ligands and demonstrates the electronic flexibility of the PYE ligand sites. In the presence of a base, the originally cis-coordinated bis-PYE ligand adopts a N,N,N-tridentate coordination mode with the two PYE units in mutual trans position. This cis-trans isomerization is reverted in presence of an acid, demonstrating a unique structural and steric flexibility of the bis-PYE ligand at palladium in addition to its electronic adaptability. The palladium complexes are active in formic acid dehydrogenation to H2 and CO2 . The catalytic performance is directly dependent on the ligand bonding mode, the nature of the ancillary ligand, the counteranion, and additives. The most active system features a bidentate bis-PYE ligand, PPh3 as ancillary ligand and accomplishes turnover frequencies up to 525 h-1 in the first hour and turnover numbers of nearly 1000, which is the highest activity reported for palladium-based catalysts to date.

Ejection velocities, age, and formation process of SPE meteoroid cluster

Context. Meteoroid clusters represent a unique opportunity to study processes of meteoroid disruptions in interplanetary space. We follow our previous work about the September epsilon Perseid (SPE) meteoroid cluster from 2016 with a detailed analysis of the observed data and cluster formation conditions. Aims. Our goal is to determine ejection velocities of the cluster members and SPE’s age, as well as to estimate the most probable formation process. Methods. We precisely determined mutual positions and masses of all meteoroids including the errors. We assumed that the massdominated meteoroid is the parent body of the cluster and that the observed positions of meteoroids are controlled by the ejection velocities and the action of solar radiation pressure. A formula for the dependence of meteoroid ejection velocities on the mutual positions, masses, and cluster age was derived. It was assumed that the time at which the initial kinetic energy of all meteoroids reached a minimum value corresponds to the age of the cluster. Knowing values and directions of ejection velocities together with meteoroid masses then allowed us to determine the most likely process of cluster formation. Results. The meteoroids occupy a volume of 66 × 67 × 50 km and are shifted in the antisolar direction by 27 km relative to the parent meteoroid. The age of the cluster is 2.28 ± 0.44 days. The ejection velocities range from 0.13 ± 0.05 m s−1 to 0.77 ± 0.34 m s−1 with a mean value of 0.35 m s−1. The ejection velocity directions are inside the cone with an apex angle of 101 ± 5°. The axis of the cone is ~45° away from the solar direction and ~34° away from the mean direction of the flux of small meteoroids’ incident on the parent meteoroid. Formation due to the separation of part of the surface due to very fast rotation is the least likely thing to occur. We estimate the rotation frequency to be about 2 Hz and the corresponding stress is several orders of magnitude lower than the predicted strength limit. It is also difficult to explain the formation of the cluster by an impact of a small meteoroid on the parent body. However, this possibility, although not very likely, cannot be completely ruled out. The most probable process is the exfoliation due to thermal stresses. Their estimated magnitude is sufficient and the derived ejection velocities are consistent with this process of formation.

Wireless Power Transfer—A Review

This paper presents the current state of knowledge in the field of wireless power transfer. The concept of such a transfer and the basic methods of its implementation are described, together with block diagrams of the necessary devices. The technologies of electrical power transfer over short and long distances are characterized. The most popular electrical power transfer technology based on the phenomenon of electromagnetic induction is discussed in great detail. The analysis of the influences of such factors as the coupling factor, the shape of the coils, the type of ferromagnetic material from which the core of the coils is made, and the mutual position of the transmitting and receiving coils are analyzed on the properties of the wireless power transfer system. The advantages and disadvantages of the used technologies are shown. Furthermore, a wireless power transfer system is presented for charging the batteries of electric vehicles. The standards of wireless power transfer are also presented, and development trends are outlined.

Method and a Device for Testing the Friction Force in Precision Pairs of Injection Apparatus of the Self-Ignition Engines

This article reviews the state of the knowledge and technology in the field of friction-loss measurements in internal combustion piston engines. The dependencies that describe the loss of energy in combustion engines and injection apparatus are presented. Currently, very little can be found in the literature on the study of frictional forces in injection apparatus, but mainly in the piston–cylinder group, so this work significantly fills that gap. The aim of this article is to construct a device and to develop a method for assessing the technical state of injector nozzles to minimize friction losses in internal combustion engines at the stages of evaluation, design, production and operation. This article presents a stand for determining the maximum friction forces due to gravity loading by water-jet control. This article also presents test results on the maximum friction force between a needle and a body of injector nozzles in piston combustion engines on a designed and purpose-built stand outside of the combustion engine. Various designs and injector nozzles are made from various types of alloy steel for marine and automotive piston internal combustion engines fueled with distillation or residual fuels, and are tested. The research concerned conventional elements for the injection apparatus as well as electronically controlled subsystems. Precision pairs of injection equipment are selected for the tests: new ones are employed after the storage period and operated in natural conditions. The elements dismantled from the internal combustion engines are tested in the presence of fuel or calibration oil of similar properties. The maximum static frictional forces under the hydrostatic loading are measured, alongside the parameters for the dynamic movement of the nozzle needles from bodies of the injector nozzle as time, speed, acceleration and dynamic force. The influence of the angular position of the needle in relation to the bodies of the precision pairs conventional internal combustion engines, the diametral clearance between the nozzle body and needle, and the surface conditions on the values of the maximum friction force are also presented. Errors in shape and position result in the uniqueness of the friction force at the mutual angular position of the needle in relation to the nozzle body, and the decrease in diametral clearance and deterioration of the surface state increase the friction losses. A model was elaborated of the influence of various factors on the value of the maximum friction force.

Researches on influence of wood sanding direction on wood gluing

The wood surface quality is most determined by the way in which it has been processed before and by the tools used for this purpose. Machining has its effect primarily on the structural shape of the surface formed after the tool–wood contact and also on the roughness of the surface obtained after a specific process. In most cases, wood surfaces of elements which are materials or semi-finished products used for further processes, including gluing or painting, are sanded with sandpaper of various grit sizes on belt sanders. This causes the structure formed on the wood surface to be unidirectional. No information is available in the literature on the influence of the direction of the post-processing structure of the glued surfaces on the gluing process. Therefore, this was the subject of this research study. Two kinds of wood glues were used, and three gluing pressures were applied. Contrary to what was expected, the effect of the mutual position of post sanding surface structures during the gluing operation on the amount of glue in the connection turned out to be of small significance. In an extreme case, the difference of a necessary minimum amount of glue was 15.1% for the same type of connection and a different position of the glued surfaces against each other. However, the kind of the glue being used and the gluing pressure have been found to have a significant effect on its amount necessary to produce a good connection.

DEEPStack-RBP: Accurate identification of RNA-binding proteins based on autoencoder feature selection and deep stacking ensemble classifier

RNA-binding proteins (RBPs) are involved in a number of biological processes such as RNA synthesis, protein folding, alternative splicing, etc. Predicting RBPs can facilitate the discovery and treatment of human diseases, such as muscle atrophy, nervous system diseases, and cancer. However, there are still various challenges in identifying RBPs using experimental methods. Computational methods, and in particular Deep Learning, are being deployed to alleviate some of these challenges and provide new avenues of investigation in the field of RBPs prediction. Here, we propose DEEPStack-RBP, a novel RBPs prediction tool based on deep learning and ensemble learning. First, conjoint triad (CT), local descriptors (LD), pseudo amino acid composition (PseAAC), multivariate mutual information (MMI) and position specific scoring matrix-transition probability composition (PSSM-TPC) are applied to extract multiple features from the proteins. Subsequently, autoencoder (AE) is used to eliminate redundancy in features, and SMOTE-ENN is employed to balance the samples by minimizing the number difference between positive and negative cases. Finally, the stacked ensemble classifier composed of bidirectional long short-term memory (BiLSTM), gated recurrent unit (GRU), and support vector machine (SVM) is used for prediction. On the training dataset RBP9873, the ACC value of DEEPStack-RBP reaches 98.76% with a MCC value of 0.9508. For the three independent test datasets of Human, S. cerevisiae and A. thaliana, the accuracy of the model is 97.16%, 97.67% and 99.57% respectively, and the MCC is 0.9405, 0.9499 and 0.9906 respectively. These results show that DEEPStack-RBP can be used as a powerful tool for RBPs prediction.

Fusion of two unrelated protein domains in a chimera protein and its 3D prediction: Justification of the x-ray reference structures as a prediction benchmark.

Proteins are naturally formed by domains edging their functional and structural properties. A domain out of the context of an entire protein can retain its structure and to some extent also function on its own. These properties rationalize construction of artificial fusion multidomain proteins with unique combination of various functions. Information on the specific functional and structural characteristics of individual domains in the context of new artificial fusion proteins is inevitably encoded in sequential order of composing domains defining their mutual spatial positions. So the challenges in designing new proteins with new domain combinations lie dominantly in structure/function prediction and its context dependency. Despite the enormous body of publications on artificial fusion proteins, the task of their structure/function prediction is complex and nontrivial. The degree of spatial freedom facilitated by a linker between domains and their mutual orientation driven by noncovalent interactions is beyond a simple and straightforward methodology to predict their structure with reasonable accuracy. In the presented manuscript, we tested methodology using available modeling tools and computational methods. We show that the process and methodology of such prediction are not straightforward and must be done with care even when recently introduced AlphaFold II is used. We also addressed a question of benchmarking standards for prediction of multidomain protein structures-x-ray or Nuclear Magnetic Resonance experiments. On the study of six two-domain protein chimeras as well as their composing domains and their x-ray structures selected from PDB, we conclude that the major obstacle for justified prediction is inappropriate sampling of the conformational space by the explored methods. On the other hands, we can still address particular steps of the methodology and improve the process of chimera proteins prediction.