Cone Type Research Articles

Research of the value of linear distortion of renewable surface of part during rotary processing of bulky items without dismantling unit

The loading and unloading units and grinding mills of raw devices have internal cone type or pipe screw perceive load of incoming and outgoing material. The main part of the support assembly is a pin. Mounting seats for the pipe screws cone have traces of deformation and work hardening, while they themselves have wear of pins and deformation of the inner and outer cylindrical working surface. In the mill body, there are constantly acting dynamic forces causing vibration, which are transmitted to the stud and inner accelerating elements. Under the influence of stress and vibration, the housing spigot is in the stress-compressed state and stretched vertically and horizontally. As a result, the insertion element is deformed and weakened in the fixture. A moving element appears in the gap leading to the fact that it drops lfeedstock and under the influence of variable loads it is destroyed, as well as the seating surfaces of the insert pin member.

Micro-cones on a liquid interface in high electric field: Ionization effects

We formulate and explore electrohydrodynamic equations for conductive liquids taking dissociation/recombination processes into account and discover a novel type of liquid cones which carry both surface and net bulk charge and can be formed on a liquid interface in an electric field. The bulk charge is generated by the corona discharge due to a high electric field at the cone apex. We establish correlation between the cone angle and physical parameters of the liquid on the one hand and the electric current passing through the cone on the other hand. It is shown that the current strongly increases when the cone angle tends to a critical value which is a function of the dielectric permittivity of the liquid. The cone stability with respect to axially symmetric perturbations is analyzed. It is shown that the cones with apex angles close to the critical angle are likely to be stable. The effect of the imposed flow on the cone apex stability is also discussed.

Electric field simulation for uniform and FGM cone type spacer with adhering spherical conducting particle in GIS

Small spherical conducting particles which may be generated due to mechanical abrasion or arcing during switching of isolators and circuit breakers strongly affect the distribution of the electric field especially if they are very adjacent or adhering to the spacer surface. The simulation of the electric field depends on the location, the size of the contaminating particle and the spacer relative permittivity. This paper studies the effect of the presence of the adhering spherical conducting particles with different sizes and locations on the electric field distribution at solid/gas interface surface and around the spacer. Cone type spacer model with uniform and function grading material (FGM) permittivity distributions has been introduced to study the effect of the presence of the spherical conducting particles on the characteristics of the electric field along and around the spacer surface. The effect of the FGM spacer with its different arrangements on the insulation characteristics along and around the spacer surface will be discussed. The electric field simulation is performed by the concept of Finite Element Method (FEM) using three-dimension simulation model.

Nonselective Wiring Accounts for Red-Green Opponency in Midget Ganglion Cells of the Primate Retina.

In primate retina, "red-green" color coding is initiated when signals originating in long (L) and middle (M) wavelength-sensitive cone photoreceptors interact antagonistically. The center-surround receptive field of "midget" ganglion cells provides the neural substrate for L versus M cone-opponent interaction, but the underlying circuitry remains unsettled, centering around the longstanding question of whether specialized cone wiring is present. To address this question, we measured the strength, sign, and spatial tuning of L- and M-cone input to midget receptive fields in the peripheral retina of macaque primates of either sex. Consistent with previous work, cone opponency arose when one of the cone types showed a stronger connection to the receptive field center than to the surround. We implemented a difference-of-Gaussians spatial receptive field model, incorporating known biology of the midget circuit, to test whether physiological responses we observed in real cells could be captured entirely by anatomical nonselectivity. When this model sampled nonselectively from a realistic cone mosaic, it accurately reproduced key features of a cone-opponent receptive field structure, and predicted both the variability and strength of cone opponency across the retina. The model introduced here is consistent with abundant anatomical evidence for nonselective wiring, explains both local and global properties of the midget population, and supports a role in their multiplexing of spatial and color information. It provides a neural basis for human chromatic sensitivity across the visual field, as well as the maintenance of normal color vision despite significant variability in the relative number of L and M cones across individuals.SIGNIFICANCE STATEMENT Red-green color vision is a hallmark of the human and nonhuman primate that starts in the retina with the presence of long (L)- and middle (M)-wavelength sensitive cone photoreceptor types. Understanding the underlying retinal mechanism for color opponency has focused on the broad question of whether this characteristic can emerge from nonselective wiring, or whether complex cone-type-specific wiring must be invoked. We provide experimental and modeling support for the hypothesis that nonselective connectivity is sufficient to produce the range of red-green color opponency observed in midget ganglion cells across the retina. Our nonselective model reproduces the diversity of physiological responses of midget cells while also accounting for systematic changes in color sensitivity across the visual field.

Blue Cone Monochromatism.

Unlike rod monochromatism, which is an autosomal recessive disease that affects all three types of cones, blue cone monochromatism (BCM) is an X-linked disease that affects only L-cones and M-cones. The rods and S-cones are normal. The estimated prevalence is 1 in 100,00 individuals.

Binocular facilitation of cone‐specific visual evoked potentials in colour deficiency

BackgroundNeural compensatory mechanisms have been proposed, which preserve the binocular visual field in glaucoma, as well as cognition in Alzheimer's disease and motor function in Parkinson's disease. It is conceivable that comparable mechanisms operate to preserve function in congenital and/or dystrophic disease. In hereditary colour vision deficiency (CVD), we observed significant facilitation in the amplitude of the binocular cone‐specific visual evoked potential (VEP) compared to the monocular amplitude for the cone type corresponding to the CVD. We propose that this finding may reflect preservation of function in hereditary colour vision deficiency.MethodsBinocular and monocular L, M and S cone‐specific VEPs were recorded from 12 colour vision deficient subjects and 17 with normal colour vision, confirmed to be CVD or normal on a battery of colour vision tests. Binocular VEP amplitudes were compared to monocular amplitudes within subjects and between subject groups.ResultsSubjects with CVDs showed binocular facilitation of VEP amplitude (enhancement more than 2.0 times; mean: 2.8 times, p = 0.0003) for the cone type corresponding to their CVD. Mean facilitation of 2.8 times exceeded binocular enhancement for other cone types within CVDs (2.8 times versus 1.2 times) and compared to colour vision normals (2.8 times versus 1.2 times).ConclusionsHereditary CVDs show binocular facilitation of cone VEP signals for the cone type corresponding to their CVD. As CVD is typically assessed with foveal stimuli, our findings using wider‐field binocular stimulation suggest that enhanced colour perception may occur in CVD across a more extensive area of visual field. These results may relate to binocular visual field enhancement in glaucoma and improved colour vision in CVD at supra‐threshold levels of stimulation.

Expression for Capacity of the Cone Type Converter of the Grain and Grain Products Sensor

The expression for the cone type transformation moisture meter capacity for grain and grain products, using which we can measure the moisture more accurately has been considered. The analytical expression for the proposed ourselves sensor construction capacity having truncated cone shape has been given. The dependence of construction capacity on the geometrical sizes of conducting compartment (height, internal and external radiuses) has been investigated. The values of the capacity by optimization sizes of the construction conducting compartment have been presented. It has been defined that the maximal capacity of the sensor equals to 9.26 pF and the capacity is nonlinear and decreasing monotonic down to zero.

Daily activity patterns influence retinal morphology, signatures of selection, and spectral tuning of opsin genes in colubrid snakes

BackgroundMorphological divergences of snake retinal structure point to complex evolutionary processes and adaptations. The Colubridae family has a remarkable variety of retinal structure that can range from all-cone and all-rod to duplex (cone/rod) retinas. To explore whether nocturnal versus diurnal activity is responsible for constraints on molecular evolution and plays a role in visual opsin spectral tuning of colubrids, we carried out molecular evolution analyses of the visual opsin genes LWS, RH1, and SWS1 from 17 species and performed morphological analyses.ResultsPhylogenetic reconstructions of the RH1 and LWS recovered major clades characterized by primarily diurnal or primarily nocturnal activity patterns, in contrast with the topology for SWS1, which is very similar to the species tree. We found stronger signals of purifying selection along diurnal and nocturnal lineages for RH1 and SWS1, respectively. A blue-shift of the RH1 spectral peak is associated with diurnal habits. Spectral tuning of cone opsins did not differ among diurnal and nocturnal species. Retinas of nocturnal colubrids had many rows of photoreceptor nuclei, with large numbers of rods, labeled by wheat germ agglutinin (WGA), and two types of cones: large cones sensitive to long/medium wavelengths (L/M) and small cones sensitive to ultra-violet/violet wavelengths (UV/VS). In contrast, retinas of diurnal species had only one row of photoreceptor nuclei, with four types of cones: large and double L/M cones, small UV/VS cones, and a second group of small cones, labeled by WGA.ConclusionsFor LWS gene, selection tests did not confirm different constraints related to activity pattern. For SWS1, stronger purifying selection in nocturnal lineages indicates divergent evolutionary pressures related to the activity pattern, and the importance of the short wavelength sensitivity at low light condition. Activity pattern has a clear influence on the signatures of selection and spectral tuning of RH1, with stronger purifying selection in diurnal lineages, which indicates selective pressure to preserve rhodopsin structure and function in pure-cone retinas. We suggest that the presence of four cone types in primarily diurnal colubrids might be related to the gain of color discrimination capacity.

Cavitation heat effect and noise of hydraulic cone throttle valve

In order to study the thermal effect and noise of cavitation in hydraulic cone type throttle valve, a cone type throttle valve cavitation experiment platform is built. With the organic glass having a better transparency as the material, the model valve was made. The pressure characteristics of five kinds of spool case cone type throttle valves were analyzed through simulation and experimental study, and the main production parts of cone type throttle valve cavitation bubble were obtained. The results show that the frequency of cone type throttle valve noise is above 8kHz. On this basis, we can determine whether the cone type throttle valve noise is the main source of noise in hydraulic system by measurement of noise spectrum. Based on the above findings, it is concluded that it is helpful for fault diagnosis of hydraulic system. The cavitation has relatively great impact on the hydraulic oil temperature flowing through the throttle valve, and its impact cannot be ignored.

Connectivity of cone photoreceptor telodendria in the zebrafish retina.

The connectivity amongst photoreceptors is critical to their function, as it underpins lateral inhibition and effective translation of stimuli into neural signals. Despite much work characterizing second-order interneurons in the outer retina, the synapses directly connecting photoreceptors have often been overlooked. Telodendria are fine processes that connect photoreceptor pedicles. They have been observed in diverse vertebrate groups, yet their roles in vision remain speculative. Here, we visualize telodendria via fluorescent protein expression in photoreceptor subtypes. We characterized short wavelength cone telodendria in adult and larval zebrafish retina. Additionally, in the larval retina, we investigated rod telodendria and UV cone telodendria in mutant and transgenic retinas with altered complements of cone types. In the adult retina, telodendria are twice as abundant and branch almost twice as often on blue cones compared to UV cones. Pedicles of neighboring UV and blue cones typically converge into contiguous pairs, despite the regular spacing of their cell bodies. In contrast to adults, larval UV cone telodendria are more numerous (1.3 times) than blue cone telodendria. UV cone telodendria are not detectably affected by ablation of blue cones, and are reduced twofold in mutant larval retina with few UV cones. We thus saw no evidence that telodendria increase in number in the absence of their typical cellular neighbors. We also found that larval rod telodendria are less abundant than short wavelength cone telodendria. In summary, we describe the development and morphology of zebrafish photoreceptor synaptic connectivity toward appreciating the function of telodendria in visual signal processing.

Anisotropic M\xfcller glial scaffolding supports a multiplex lattice mosaic of photoreceptors in zebrafish retina

BackgroundThe multiplex, lattice mosaic of cone photoreceptors in the adult fish retina is a compelling example of a highly ordered epithelial cell pattern, with single cell width rows and columns of cones and precisely defined neighbor relationships among different cone types. Cellular mechanisms patterning this multiplex mosaic are not understood. Physical models can provide new insights into fundamental mechanisms of biological patterning. In earlier work, we developed a mathematical model of photoreceptor cell packing in the zebrafish retina, which predicted that anisotropic mechanical tension in the retinal epithelium orients planar polarized adhesive interfaces to align the columns as cone photoreceptors are generated at the retinal margin during post-embryonic growth.MethodsWith cell-specific fluorescent reporters and in vivo imaging of the growing retinal margin in transparent juvenile zebrafish we provide the first view of how cell packing, spatial arrangement, and cell identity are coordinated to build the lattice mosaic. With targeted laser ablation we probed the tissue mechanics of the retinal epithelium.ResultsWithin the lattice mosaic, planar polarized Crumbs adhesion proteins pack cones into a single cell width column; between columns, N-cadherin-mediated adherens junctions stabilize Müller glial apical processes. The concentration of activated pMyosin II at these punctate adherens junctions suggests that these glial bands are under tension, forming a physical barrier between cone columns and contributing to mechanical stress anisotropies in the epithelial sheet. Unexpectedly, we discovered that the appearance of such parallel bands of Müller glial apical processes precedes the packing of cones into single cell width columns, hinting at a possible role for glia in the initial organization of the lattice mosaic. Targeted laser ablation of Müller glia directly demonstrates that these glial processes support anisotropic mechanical tension in the planar dimension of the retinal epithelium.ConclusionsThese findings uncovered a novel structural feature of Müller glia associated with alignment of photoreceptors into a lattice mosaic in the zebrafish retina. This is the first demonstration, to our knowledge, of planar, anisotropic mechanical forces mediated by glial cells.

Experimental and numerical investigations on collapse properties of capped-end frusta tubes with circular triggers under axial quasi-static loading

In this paper, collapse properties of the capped-end cone tubes made from steel alloy 430 with circular holes under quasi-static axial loading have been studied experimentally and numerically. Simulations were performed using finite element LS-Dyna software and 11 types of cone with various number of holes (3, 4 and 5) and heights (20,40 and 60 mm relative to bottom base of cone) in four different thicknesses (0.2, 0.4, 0.6 and 1 mm), so, 44 different states were totally simulated and the collapse properties of them were extracted. The samples with the thickness of 0.2 mm were tested on an experimental basis in order to ensure the accuracy of the simulation results. Comparing the obtained results indicates good agreement between the experimental and numerical data. According to the obtained results, it was found that open end absorbers are more efficient compared to similar capped-end structures. Also, it was revealed that creating holes in the capped-end cone decreases the maximum force and increases crush force efficiency. In addition, it was found that creating hole farther away from the underlying base is more effective for improving the collapse properties. In the final section, the effects of thickness on the collapse properties were evaluated. The obtained results in this study can be a good guidance for investigation on the effect of discontinuity on collapse properties.

An investigation on deformation behaviors of energy absorbers for passenger coaches

Thin-walled structures is used commonly as energy absorbers at the front and back of the coaches. These parts should be designed to minimize the damage to the vehicle and prevent the passengers from fatality and/or injury by absorbing the collision energy in railway transportation. In this paper, deformation behaviors of tube like structures with truncated cone under the axial impact load were investigated by means of finite element analysis (FEA). The energy absorbers having tube like structures were modelled at the same weight and have three different wall thickness and taper angle. As a result of FEA, the performances of straight and truncated cone type energy absorbers were compared in terms of energy absorption capacities and an optimization study was done to determine the effects of thickness and taper angle on energy absorbing performances of the members. The analysis of variance in 95% confidence level was applied in order to determine the effects of design parameters on total efficiency (TE). Besides, optimum design parameters for TE were determined by using Taguchi optimization methodology. Thickness was found as the most significant parameter on total efficiency with 60.52% percentage contribution ratio according to ANOVA results.

A 3D-printed modular device for imaging the brain of small birds

BackgroundOne potential barrier to using in vivo imaging in any new animal species is solving the basic problem of how to hold animals safely and securely during scans. New methodIn this paper, we describe the design, fabrication, use, and positional reproducibility of a 3D-printed plastic device (the Avian Imaging Device, or AID) for imaging the brain of 1 or 2 small songbirds. We designed two different types of head cones to use with this device: one that was not contoured and designed for anesthesia induction, and one contoured to the shape of a house sparrow head, designed to be used with a pre-anesthetized animal. ResultsCompared to no holder, using the AID with both contoured and non-contoured head cones significantly reduced the amount of translation necessary to align the head in pairs of CT scans (by 78% and 90%, respectively); using the contoured head cone also significantly reduced the amount of rotation necessary for head alignment in registering pairs of scans (by 90%). Comparison with existing method(s)Using an animal holder that can not only securely hold animals but which has high positional reproducibility is essential to take advantage of the maximum resolution possible with small animal imaging. 3D-printed materials are also compatible with PET and CT, environmentally stable, and fast and inexpensive to make. ConclusionsResearchers can learn from the design of the AID and use our CAD models as a starting point for fabricating devices for multiple small-animal imaging needs.

Nonlinear Dirac cones

Physics arising from two-dimensional~(2D) Dirac cones has been a topic of great theoretical and experimental interest to studies of gapless topological phases and to simulations of relativistic systems. Such $2$D Dirac cones are often characterized by a $\pi$ Berry phase and are destroyed by a perturbative mass term. By considering mean-field nonlinearity in a minimal two-band Chern insulator model, we obtain a novel type of Dirac cones that are robust to local perturbations without symmetry restrictions. Due to a different pseudo-spin texture, the Berry phase of the Dirac cone is no longer quantized in $\pi$, and can be continuously tuned as an order parameter. Furthermore, in an Aharonov-Bohm~(AB) interference setup to detect such Dirac cones, the adiabatic AB phase is found to be $\pi$ both theoretically and computationally, offering an observable topological invariant and a fascinating example where the Berry phase and AB phase are fundamentally different. We hence discover a nonlinearity-induced quantum phase transition from a known topological insulating phase to an unusual gapless topological phase.

On <i>C</i><sup>1, <i>β</i></sup> density of metrics without invariant graphs

We show that given any $C^{\infty}$ Riemannian structure $(T^{2},g)$ in the two torus, $\epsilon >0$ and $\beta \in (0,\frac{1}{3})$, there exists a $C^{\infty}$ Riemannian metric $\bar{g}$ with no continuous Lagrangian invariant graphs that is $\epsilon$-$C^{1,\beta}$ close to $g$. The main idea of the proof is inspired in the work of V. Bangert who introduced caps from smoothed cone type $C^{1}$ small perturbations of metrics with non-positive curvature to get conjugate points. Our new contribution to the subject is to show that positive curvature cone type small perturbations are ``less singular' than non-positive curvature cone type perturbations. Positive curvature geometry allows us to get better estimates for the variation of the $C^{1}$ norm of the singular cone in a neighborhood of its vertex.

Arithmetics and combinatorics of tropical Severi varieties of univariate polynomials

We give a description of the tropical Severi variety of univariate polynomials of degree n having two double roots. We show that, as a set, it is given as the union of three explicit types of cones of maximal dimension n − 1, where only cones of two of these types are cones of the secondary fan of {0,..., n}. Through Kapranov’s theorem, this goal is achieved by a careful study of the possible valuations of the elementary symmetric functions of the roots of a polynomial with two double roots. Despite its apparent simplicity, the computation of the tropical Severi variety has both combinatorial and arithmetic ingredients.

How redundant are luminance and chrominance information in natural scenes?

Color vision is an impressive ability of the human visual system. Three different types of cones in the retina, and then three postreceptoral cone-opponent mechanisms enable us to extract both luminance and chromatic information from our environment. Theories of efficient coding argue that the visual system evolved this way to optimally process natural scenes. Therefore, the study of statistical properties of natural images has great potential value to expand our understanding of visual perception. From that perspective, a central question is to characterize the role of chromatic information: in natural scenes, what information can be extracted from chromatic channels that is not already present in luminance? The literature on this point is contradictory. On the one hand, several studies have investigated the joint distribution of luminance and chrominance, finding that luminance and chromatic edges are not independent (Fine et al. 2003) and that most edges are defined by luminance contrast with color information being redundant (Zhou & Mel 2008). On the other hand, Hansen and Gegenfurtner (2009) showed using mutual information that luminance and chromatic edges constitute relatively independent sources of information and that their independence increases along successive stages of visual processing. Here we improve and extend their analysis, using ~1000 images taken from the McGill calibrated color image database (Olmos & Kingdom, 2004) to quantify the redundancy of luminance and chrominance information in each image individually. While we replicate the main findings of Hansen and Gegenfurtner (2009), we also find that the estimated amount of mutual information depends on how the images are processed. The most critical step is divisive normalization, a late stage in the processing pipeline. How redundant chrominance and luminance are, may thus depend on the precise definition of these two quantities, explaining some inconsistencies in the literature.

Maxwell's spot measurements in changing white light spectra

The macular pigment covering the fovea maximally absorbs at 460 nm and minimally beyond approximately 540 nm (Bone et al, 1992). Consequently, foveal cones continuously receive less short-wavelength light than cones in surrounding areas, yet in normal circumstances we do not perceive a darker or colored spot in the central visual field. The difference in spectral transmission can be made visible by looking through a dichroic filter to a white surface or by alternately looking at a blue and yellow field. The resulting spot appearance, which fades with time, is called the Maxwell spot. Here, we show that the phenomenon can also be demonstrated by alternately looking at two light fields of similar white appearance, but differing in spectral composition (E1 and E2). When changing from E1 to E2, the color appearance of the spot is complementary to that when changing from E2 to E1. We measured the color appearance of both these spots, using successive haploscopic color matching. The Maxwell spots were generated by exposing the left eye for 6 seconds to E1 and E2 alternated at 0.5 Hz. A synchronized audio signal indicated which of the two Maxwell spots was to be matched. The observers used a computer mouse to navigate through (a*,b*) color space to match the color in the right eye to the perceived color of the Maxwell spot in the left eye, while keeping both eyes at equal (constant) luminance. The spectral distributions E1 and E2 and the color matches were produced by a multi-primary LED light source. Our results indicate that the Maxwell spots are due to differential local chromatic adaptation, i.e. independent sensitivity adjustments of the three cone types. We conclude that even small differences in light appearance may already elicit the Maxwell spot. Meeting abstract presented at VSS 2017

The Criteria of Thickened Liquid for Dysphagia Management in Japan.

In Japan, the viscosity of thickened liquids is different among hospitals and nursing homes. In order to standardize viscosity of thickened liquids, the dysphagia diet committee of the Japanese Society of Dysphagia Rehabilitation developed the Japanese Dysphagia Diet 2013 (JDD2013). To decide on a definition of thickened liquids, the committee reviewed categories from other countries. Especially, the criteria of the USA and Australia were used as references. The definition had three levels: mildly thick, moderately thick, and extremely thick. Then a sensory evaluation by health care workers was carried out to decide the viscosity range of each level, and a draft document was made. After collecting public comments, follow-up experiments using thickened water with thickeners using xanthan gum were performed, and the JDD2013 (Thickened Liquid) was determined. The JDD2013 (Thickened Liquid) evaluated the drinking properties, visual properties, and viscosity values of each level. The shear rate of 50s-1 was adopted to measure the viscosity with a cone and plate type viscometer to duplicate the measurement criteria used by the USA. We also set the values of the JDD2013 with the Line Spread Test to promote the use of guidelines in clinical practice. We believe the JDD2013 standards help hospitals and other settings that care for people with dysphagia to use the same thickness level and the same labels. In the future, the JDD2013 levels will be compared with new international guidelines to help with international understanding of the JDD2013 levels.