Central Field Research Articles

EXPRESS: From the Margins to the Mainstream: Entrepreneurial Theorization and the Spread of a New Collective Identity within a Mature Organizational Field

We study the effects of entrepreneurial theorization on the spread of a new collective identity within a mature organizational field. Mature fields are characterized by dominant logics, entrenched practices, and stable patterns of interaction, resulting in isomorphism and inertia. Yet, mature fields do change, often as a result of entrepreneurial activity. Whereas prior work has focused on the creation of “oppositional” niches within mature fields, we focus on an identity movement that transforms the core of a field. We do this within the context of the Canadian wine field, a field that remained stable from the end of Prohibition through the 1970s. For decades, large incumbents projected a European identity for their wines and gave these wines “faux” European names. In contrast, pioneering entrepreneurs projected a distinctly Canadian identity for their wines, an identity that was ultimately adopted by incumbents. In this way, domestic wine in Canada became tied to place rather than divorced from it. We show how entrepreneurial theorization of the “Canadian wine” identity by small producers and identity pioneers spread to the center of the field, and how the effects of theorization depended on the authenticity of these theorizers. We also suggest that an identity movement that engages incumbents rather than seeks to create an oppositional category is more likely to reach the center of a mature field.

Conformally invariant random fields, Liouville quantum gravity measures, and random Paneitz operators on Riemannian manifolds of even dimension

AbstractFor large classes of even‐dimensional Riemannian manifolds , we construct and analyze conformally invariant random fields. These centered Gaussian fields , called co‐polyharmonic Gaussian fields, are characterized by their covariance kernels k which exhibit a precise logarithmic divergence: . They share a fundamental quasi‐invariance property under conformal transformations. In terms of the co‐polyharmonic Gaussian field , we define the Liouville Quantum Gravity measure, a random measure on , heuristically given as and rigorously obtained as almost sure weak limit of the right‐hand side with replaced by suitable regular approximations . In terms on the Liouville Quantum Gravity measure, we define the Liouville Brownian motion on and the random GJMS operators. Finally, we present an approach to a conformal field theory in arbitrary even dimension with an ansatz based on Branson's ‐curvature: we give a rigorous meaning to the Polyakov–Liouville measure and we derive the corresponding conformal anomaly. The set of admissible manifolds is conformally invariant. It includes all compact 2‐dimensional Riemannian manifolds, all compact non‐negatively curved Einstein manifolds of even dimension, and large classes of compact hyperbolic manifolds of even dimension. However, not every compact even‐dimensional Riemannian manifold is admissible. Our results concerning the logarithmic divergence of the kernel rely on new sharp estimates for heat kernels and higher order Green kernels on arbitrary closed manifolds.

Shock wave propagation in a real gas with or without gravitational field in the presence of magnetic field and monochromatic radiation via group invariance method

PurposeThis article aims to find the similarity solutions for the one-dimensional motion of spherical symmetric shock wave in non-ideal gas influenced by the azimuthal magnetic field and monochromatic radiation in the presence or absence of gravitational field. This paper also aims to study the effects of physical parameters on the strength of shock wave, and on the flow variables in the flow-field region behind the shock front.Design/methodology/approachThe Roche model is used to describe the gravitational field effects due to a massive nucleus at the point of symmetry. To derive the similarity solutions, the Lie group symmetry method has been used. Also, the numerical solutions to the present problem are obtained by using Rung–Kutta method of the fourth order with the use of Mathematica software. The effects of variation in the parameter of non-idealness of the gas, the gravitation parameter, the strength of the ambient magnetic field and the adiabatic index of the gas on the shock wave, and on the flow variables is discussed. A comparative study between with and without gravitational field is also, made.FindingsFor different choices of the arbitrary constants that appeared in the solution of infinitesimal generators, we have obtained seven distinct cases of similarity solutions. In the absence of the gravitational field, the similarity solution exists to the power and exponential law shock paths, but in the presence of gravitational field, the similarity solution exists to the power law shock path case only. In the absence of gravitational field, the shock strength is enhanced in the exponential law shock path case in comparison to the power law shock path case. It is found that the shock wave decays with an increase in the value of the adiabatic exponent, the strength of magnetic field, non-idealness of the gas or gravitational parameter.Research limitations/implicationsThe consideration of medium under the influence of gravitational field due to a heavy nucleus at the center and presence of magnetic field decrease the shock strength. This result may be helpful in designing space vehicle and jet engine.Practical implicationsThe result of the present study may be used in the analysis of data from the measurements by space craft in the solar wind and in neighborhood of the Earth’s magnetosphere.Social implicationsThe obtained results may be used for mankind.Originality/valueThe study of spherical shock wave propagation influenced by monochromatic radiation and azimuthal magnetic field in a non-ideal gas with or without gravitational field has yet to be discussed by any authors by using the Lie group symmetry method. In this article, we have discussed all possible cases of similarity solutions using the Lie group symmetry method, which is not studied by anyone as known to us.

Effect of Neem Cake, Neem Oil and Plant Extracts on Purple Blotch of Onion (Allium cepa L.) Caused by Alternaria porri (Ellis) Cif.

The present study was conducted to evaluate the Effect of neem cake, plant extracts and neem oil on purple blotch of onion (Allium cepa L.) caused by Alternaria porri (Ellis) Cif. Six different treatments were tested in a randomized block design with 3 replications at the Central Research Field, Department of Plant Pathology, Sam Higginbottom University of Agriculture, Technology and Sciences, Prayagraj during Rabi season of 2023. The results should that the minimum per cent disease intensity was recorded in T1Neem cake + Neem oil (31.72), T5 Neem cake + Eucalyptus leaf extract (37.40). bulb weight of onion (71.13g), bulb diameter (7.13cm), bulb yield per plot (2.106kg), yield (105.317 q/ha) and benefit cost ratio (1: 4.42) were found in T1Neem cake + Neem oil (31.72) when compared to untreated check and other treatments.

Validation of the European visual field standards for driving: A driving simulator-based study.

To determine whether we could establish evidence-based pass/fail criteria for perimetry in the context of the European visual field standards for driving. This two-centre, cross-sectional study included participants with binocular visual field loss that had led to revocation of a group-1 driving licence. The participants underwent cognitive and binocular visual testing, including the European Driving Test (EDT), a perimetry algorithm that adheres to the European visual field standards. We used a high-fidelity driving simulator to compare the driving ability of these participants with healthy controls. Two driving instructors classified each driving test as passed or failed. Receiver operating characteristic (ROC) analysis and area under the curve (AUC) determined the ability of perimetry to discriminate between passed and failed driving tests. The study included 70 participants with visual field loss and 37 controls. A non-significantly higher proportion of controls passed the driving test (75% vs. 63%; p = 0.22). In ROC analysis, contrast sensitivity performed best (AUC of 0.73), followed by NEI VFQ-25 (AUC of 0.64). Peripheral visual field (AUC of 0.56) and central visual field (AUC of 0.47) performed weaker. Combining the central and peripheral visual field, and their interaction, increased AUC to 0.63. Perimetry was a poor predictor of simulator-based driving test result, and we could not establish appropriate pass/fail criteria for the European visual field standards. Because perimetry is not an accurate diagnostic tool for fitness to drive, a practical driving assessment should be performed in case of doubt.

Strain analysis and preliminary test of an all-superconducting high-field magnet generating 32.4 T direct-current magnetic field

Abstract A higher available magnetic field can give more flexibility for significant research and constructions. Inserting feasible high-temperature-superconducting (HTS) magnet inside low-temperature-superconducting (LTS) external is becoming an efficient method to build ultra-high-field (UHF) magnets. However, HTS insert magnets exhibited concentration of magnetic strain during the energization, significantly owing to the screening-current effect. This phenomenon affect the structural integrity of HTS magnets, posing a difficulty for UHF magnets to reach a center field larger than 30 T. In this paper, we report the recent progress of the 35 T all-superconducting UHF magnet project. The full-cycle development of this homemade UHF magnet was a strong collaboration with multiple domestic institutions in China. We used commercial REBa2Cu3O7-x (RE = rare earth element, REBCO) conductors to wind the 20 T HTS insert. Specifically, we optimized the electromagnetic design of this HTS insert with consideration of screening-current induced strain. We applied the no-insulation and metal-as-insulation winding techniques simultaneously to balance the time constant of the two nested REBCO coils. During the excitation test, the HTS insert maintained a 256 A operation current as designed for nearly 18 hours. With the energization of LTS external magnet, the entire facility reached a center field larger than 20 T for 16 hours, 30 T for 6.35 hours and 32 T for 2 hours. It finally reached a 32.4 T center field, at which point the LTS external quenched, inducing the HTS insert to quench as well. After quench, the HTS magnet can maintained 229 A operation current during the postmortem standalone test. This 32.4 T result exhibits effectiveness of considering the screening-current induced strain to enhance the structural integrity of REBCO magnets, and verifies the high reliability of REBCO magnets by generating a long-duration high field environment without any quench accident originating from the REBCO magnet.

Effect of Neem Oil in Combination with Propiconazole and Organic Amendments on Anthracnose (Colletotrichum lindemuthianum) of Cowpea (Vigna unguiculata L.)

The cowpea (Vigna unguiculata) is an annual herbaceous legume from the genus Vigna. Anthracnoses (Colletotrichum lindemuthianum) is a serious disease in cowpea growing areas and occurs as pre-harvest as well as post-harvest brown to black spots appear on the leaves. Neem oil at different concentrations (0.5%, 1%,1.5%, and 2%) along with Propiconazole were tested @ 0.1% in vivo during Kharif 2023 for their efficacy against disease incidence, plant growth and yield parameters of Cowpea at the Central Research Field of the Sam Higginbottom University of Agriculture, Technology and Sciences, Prayagraj. The results of the present investigation revealed that it significantly reduced the disease incidence. Among the treatments the minimum disease intensity (%) at 75 DAS was recorded in T5 – Neem oil (2 ml/L) + Propiconazole 25 EC (0.1%) + VC@10gm/kg +SMC@10gm/kg (Foliar spray) was found to be significantly most effective treatment against Anthracnose (Colletotrichum lindemuthianum) on Cowpea and recorded minimum disease intensity (%) at 30, 45, 60 and 75 DAS, maximum plant height (cm), maximum number of branches, maximum yield (t/ha) and highest B:C ratio. The findings of the present experiment are limited to one crop season under Prayagraj agro-climatic conditions, as such to validate the present findings; more such experiments should be carried out in the future.

Eco-friendly Management of Alternaria Leaf Spot of Brinjal (Solanum melongena L.)

Among vegetables, brinjal or eggplant is an economically important vegetable crop and second major vegetable crop next to potato in India. This crop suffers from various diseases, among different fungal diseases of brinjal, Alternaria leaf spot caused by Alternaria alternata has currently become one of the most important diseases for all brinjal varieties. Loss due to the disease has been estimated up to 25-30 per cent. Therefore, present investigation was undertaken at Central Research Field of Sam Higginbottom University of Agriculture, Technology And Sciences, Prayagraj during the Kharif of 2023-2024, for the management of leaf spot using botanicals, bio-agent, cow urine and a fungicide (treated check) for their efficacy in vivo against Alternaria leaf spot of brinjal incited by Alternaria alternata. Effects of different botanicals, bio-agent and cow urine were evaluated on different growth, disease management and yield parameters of brinjal crop under field condition by foliar spray of botanicals, cow urine and a bio-agent, along with seedling treatment with Trichoderma viride at selected concentration. The effects of treatments on growth parameter were recorded i.e. maximum plant height at 30 DAT (22.78 cm), 60 DAT (37.16 cm), 90 DAT (53.87 cm) and maximum number of leaves at 30 DAT (10.83), 60 DAT (31.80), 90 DAT (47.33) and maximum number of branches at 30 DAT (4.23), 60 DAT (11.40), 90 DAT (13.83). Among the treatments, neem leaf extract + Trichoderma viride was recorded significantly reducing disease intensity at 45 DAT (10.32%), 60 DAT (16.11%), 75 DAT (27.93%) of brinjal followed by clove extract + Trichoderma viride and Trichoderma viride + T. viride as compared to mancozeb (treated check) and control. The maximum yield was found to be in neem leaf extract + Trichoderma viride i.e. (16.63 t/ha) followed by clove extract + Trichoderma viride, and Trichoderma viride + T. viride as compared to mancozeb (treated check) and control and the most economical treatment was Neem leaf extract + Trichoderma viride i.e. (1:2.62).

Damage evolution simulation and lifetime prediction for composite blades under continuous droplet impacts

Offshore wind power generation is a promising technology in renewable energy applications due to its high reserves of wind energy in sea areas. To improve the energy transformation efficiency, the blade length of the offshore wind turbines has become larger and larger, and it has made rain erosion be one of the most frequent failures during the turbine operation. As the natural rainfall is stochastic in spatial and time domains, it is difficult to depict the damage evolution process caused by rain impact exactly. Therefore, regular and continuous droplet impact simulation and experiments present an alternative methodology for this issue. With the composite structure of the blade and deformability of the liquid droplet in consideration, a fluid solid interaction model will be established to investigate the impact response and subsequent damage evolution. In which, the Smooth Particle Hydrodynamics (SPH) model is utilized to depict the constitutive relationship within the droplet, and Finite Element Method (FEM) is used to construct the Representative Volume Element (RVE) model of the blade leading edge. The impact process is simulated first to obtain the impact pressure distribution at the contact center and velocity field in the droplet. Furthermore, the stress wave propagation in the blade multilayer structure can be analyzed. Owing to the multiaxial fatigue feature of the continuous droplet impact, the continuum damage mechanics is integrated with the fatigue criterion and the Jump-in-Cycle procedure is used to simulate the high-cycle fatigue process. The damage factor distribution on the blade coating surface and its influence on mechanical properties are analyzed. Thereafter, the droplet impact fatigue life can be accumulated based on Miner’s linear rules. The theoretical achievements are validated by experimental data provided by Rain Erosion Testing (RET), which shows a good agreement between each other. As a result, V-N curves and D-N curves, i.e. quantitative relationship between droplet falling conditions and impact fatigue life, are established. The achievements in this study can provide an effective tool for rain erosion mechanism analysis and life prediction in industrial applications.

7219 Ocular Findings in Jansen Metaphyseal Chondrodysplasia

Abstract Disclosure: F. Obiezu: None. K. Pan: None. A. Ninan: None. K.L. Roszko: None. L.S. Weinstein: None. C.R. Ferreira: None. R.I. Gafni: None. T. Magone De Quadros Costa: None. M.T. Collins: None. S. Jha: None. Jansen Metaphyseal Chondrodysplasia (JMC) is an ultra-rare disorder, with only 30 patients estimated to have the disease globally. It is caused by heterozygous pathogenic variants in PTHR1 that result in constitutive activation of parathyroid hormone type 1 receptor (PTHR1) signaling. A detailed description of craniofacial manifestations of the disease is lacking. Here we characterize the ophthalmological manifestations in patients with JMC. Six patients (4 males, 67%) with genetically confirmed JMC underwent a detailed ophthalmological evaluation, spectral-domain optical coherence tomography (OCT), craniofacial CT and 18F-NaF PET/CT scans. Median age at the time of the visit was 27.5 [IQR: 29] years. On physical examination, all patients were noted to have widely spaced eyes; 5 of the 6 had down slanted palpebral fissures, proptosis, or ptosis. Two patients had incomplete or defective closure of the eyelids (lagophthalmos), of which one had a history of progressive right facial nerve palsy with profuse epiphora. The second patient had central visual field defects, bilateral moderate optic disc pallor and bilateral retinal nerve fiber layer (RNFL) atrophy on OCT exam with bilateral optic canal narrowing on CT. Notably, comparison of these findings with a prior scan performed 5 years earlier showed progressive decrease in RNFL bilaterally. This patient had a history of prolonged intravenous bisphosphonate therapy, initiated in infancy for hypercalcemia and continued for over a decade. A third patient had normal vision, subtle temporal pallor of the optic nerve heads on dilated fundus exam, normal average RNFL, but decreased retinal ganglion cell layer analysis (GCA) on OCT. GCA was decreased in 4 of the 6 patients compared to age-matched reference range indicating a chronic optic nerve atrophic process. These data represent the first comprehensive report of the ophthalmologic findings in a cohort of patients with JMC. They demonstrate that patients with JMC have significant eye findings that appear to be more prevalent and pronounced with age. This suggests age-related, progressive optic neuropathy, which can be assessed by demonstrating OCT retinal GCA and RNFL loss and, may be a feature of JMC. The benefit and effect of long-term bisphosphonate therapy in patients with JMC remains unclear. Patients with JMC should undergo regular ophthalmologic examination including optic nerve OCT, visual field testing, and craniofacial imaging. Presentation: 6/1/2024

Application of FFBP neural network to the prediction of swirling flow

Since ancient times, man has been seeking to improve in the field of transportation and energy consumption, as the combination of optimal energy consumption and not polluting the environment in exchange for obtaining a better return made him constantly searching for optimal methods in the field of anxiety and industry based on combustion. The swirl or vortex flow is one of the most important discoveries of the last century seeking to develop combustion, as research is still focused on it in many aspects, whether in terms of the shape of the rotational areas it forms. This study aims to determine the extent to which artificial intelligence can predict the characteristics of the Swirl flow. The model adopted experimental data of the Swirl flow, both descriptive and positional data as inputs and horizontal, vertical, and kinetic energy as outputs for several positions within the combustion chamber. The results indicate that the model can capture the spatial characteristics of the vortex flow field and the combined Learning of the relationship between the input and output parameters. The results of the velocity density distribution and the position of the vortex center of the vortex flow field agree well with the experimental results. The generated prediction model has good prediction accuracy based on previously observed datasets and can reconstruct the vortex flow field. In addition, it can perform inductive prediction on a previously unseen dataset and has some generalization ability. Finally, this study suggests that many potential architectures have applications based on the induction prediction model created here.

Development of a high current density, high temperature superconducting cable for pulsed magnets

Abstract A low AC loss Rare Earth Barium Copper Oxide (REBCO) cable, based on the VIPER cable technology has been developed by Commonwealth Fusion Systems for use in high field, REBCO based tokamaks. The new cable is composed of partitioned and transposed copper ‘petals’ shaped to fit together in a circular pattern with each petal containing a REBCO tape stack and insulated from each other to reduce AC losses. A stainless steel jacket adds mechanical robustness—also serving as a vessel for solder impregnation—while a tube runs through the middle for cooling purposes. Additionally, fiber optic sensors are placed under the tape stacks for quench detection. To qualify this design, a series of experiments were conducted as part of the SPARC tokamak Central Solenoid Model Coil program—to retire the risks associated with full scale, fast ramping, high flux HTS Central Solenoid (CS) and Poloidal Field (PF) coils for tokamak fusion power plants and net energy demonstrators. These risk study and risk reduction experiments include (1) AC loss measurement and model validation in the range of ~5 T/s, (2) an IxB electromagnetic loading of over 850 kN/m at the cable level and up to 300 kN/m at the stack level, (3) a transverse compression resilience of over 350 MPa, (4) manufacturability at tokamak relevant speeds and scales, (5) cable to cable joint performance, (6) fiber optic based quench detection speed, accuracy, and feasibility, and (7) overall winding pack integration and magnet assembly. The result is a cable technology, now referred to as PIT VIPER, with AC losses that measure fifteen times lower (at ~5 T/s) than its predecessor technology; a 2% or lower degradation of critical current (Ic) at high IxB electromagnetic loads; no detectable Ic degradation up to 570 MPa of transverse compression on the cable unit cell; end to end magnet manufacturing, consistently producing Ic values within 7% of the model prediction; cable to cable joint resistances at 20 K on the order of ~15 nΩ; and fast, functional quench detection capabilities that do not involve voltage taps. This cable technology will be tested comprehensively in a Central Solenoid Model Coil to prove its readiness for compact, high field tokamak operation.

Effects of dark matter on the spontaneous scalarization in neutron stars

Dark matter, an important portion of compact objects, can influence different phenomena in neutron stars. The spontaneous scalarization in the scalar-tensor gravity has been proposed for neutron stars. Here, we investigate the spontaneous scalarization in dark matter admixed neutron stars. Applying the dark matter equations of state, we calculate the structure of scalarized neutron stars containing dark matter. The dark matter equations of state are based on observational data from the rotational curves of galaxies and the fermionic self-interacting dark matter. Our results verify that the spontaneous scalarization is affected by the dark matter pressure in neutron stars. Depending on the central density of scalarized dark matter admixed neutron stars, the dark matter pressure alters the central scalar field. The increase of dark matter pressure in low-density scalarized stars amplifies the central scalar field. However, the pressure of dark matter in high-density scalarized stars suppresses the central scalar field. Our calculations confirm that the stars in the merger event GW170817 and in the low-mass X-ray binary 4U 1820-30 can be scalarized dark matter admixed neutron stars.

A Child-Friendly Wearable Device for Quantifying Environmental Risk Factors for Myopia.

In the past few decades, the prevalence of myopia, where the eye grows too long, has increased dramatically. The visual environment appears to be critical to regulating the eye growth. Thus, it is very important to determine the properties of the environment that put children at risk for myopia. Researchers have suggested that the intensity of illumination and range of distances to which a child's eyes are exposed are important, but this has not been confirmed. We designed, built, and tested an inexpensive, child-friendly, head-mounted device that can measure the intensity and spectral content of illumination approaching the eyes and can also measure the distances to which the central visual field of the eyes are exposed. The device is mounted on a child's bicycle helmet. It includes a camera that measures distances over a substantial range and a six-channel spectral sensor. The sensors are hosted by a light-weight, battery-powered microcomputer. We acquired pilot data from children while they were engaged in various indoor and outdoor activities. The device proved to be comfortable, easy, and safe to wear, and able to collect very useful data on the statistics of illumination and distances. The designed device is an ideal tool to be used in a population of young children, some of whom will later develop myopia and some of whom will not. Such data would be critical for determining the properties of the visual environment that put children at risk for becoming myopic.

Unveiling complex magnetic field configurations in red giant stars

The recent measurement of magnetic field strength inside the radiative interior of red giant stars has opened the way toward full 3D characterization of the geometry of stable large-scale magnetic fields. However, current measurements, which are limited to dipolar (ℓ = 1) mixed modes, do not properly constrain the topology of magnetic fields due to degeneracies on the observed magnetic field signature on such ℓ = 1 mode frequencies. Efforts focused toward unambiguous detections of magnetic field configurations are now key to better understand angular momentum transport in stars. We investigated the detectability of complex magnetic field topologies (such as the ones observed at the surface of stars with a radiative envelope with spectropolarimetry) inside the radiative interior of red giants. We focused on a field composed of a combination of a dipole and a quadrupole (quadrudipole) and on an offset field. We explored the potential of probing such magnetic field topologies from a combined measurement of magnetic signatures on ℓ = 1 and quadrupolar (ℓ = 2) mixed mode oscillation frequencies. We first derived the asymptotic theoretical formalism for computing the asymmetric signature in the frequency pattern for ℓ = 2 modes due to a quadrudipole magnetic field. To access asymmetry parameters for more complex magnetic field topologies, we numerically performed a grid search over the parameter space to map the degeneracy of the signatures of given topologies. We demonstrate the crucial role played by ℓ = 2 mixed modes in accessing internal magnetic fields with a quadrupolar component. The degeneracy of the quadrudipole compared to pure dipolar fields is lifted when considering magnetic asymmetries in both ℓ = 1 and ℓ = 2 mode frequencies. In addition to the analytical derivation for the quadrudipole, we present the prospect for complex magnetic field inversions using magnetic sensitivity kernels from standard perturbation analysis for forward modeling. Using this method, we explored the detectability of offset magnetic fields from ℓ = 1 and ℓ = 2 frequencies and demonstrate that offset fields may be mistaken for weak and centered magnetic fields, resulting in underestimating the magnetic field strength in stellar cores. We emphasize the need to characterize ℓ = 2 mixed-mode frequencies, (along with the currently characterized ℓ = 1 mixed modes), to unveil the higher-order components of the geometry of buried magnetic fields and to better constrain angular momentum transport inside stars.

Optimization study of proton exchange membrane fuel cell parameters based on Taguchi method for central spiral flow field

Optimization study of proton exchange membrane fuel cell parameters based on Taguchi method for central spiral flow field

The Counseling Center Field’s Relationship with the Mental Health Marketplace

ABSTRACT One of the most significant changes to college mental health is the growing use of telehealth vendors to provide, extend, or augment mental health services provided by college and university counseling centers. In a time of sharply increased demand for services, new investments in the mental health marketplace, and the perception that mental health is a “crisis,” the relationships between counseling centers and mental health vendors are increasingly important. This paper provides an overview of these new relationships, briefly reviews relevant history and context, and explores the relationship dynamics shaping this space. In addition, this paper reviews common fears and worries faced by counseling centers when considering vendors, addresses some of the confusion surround vendor/service types, and offers a set of suggestions for the inevitable future relationship in the development of guiding principle and standards.

Analysis of Schlemm's Canal Measurement and Evaluation with Fourier-Domain Optical Coherence Tomography in Primary Open-Angle Glaucoma

The most common cause of permanent vision loss or blindness in the world is glaucoma. Primary Open Angle Glaucoma (POAG) develops when the eye drainage canals clog over time, increasing intraocular pressure and damaging the optic nerve. In POAG, an ophthalmology examination usually shows an open anterior chamber and chronic, irreversible multifactorial optic neuropathy followed by central visual field loss. OCT is specifically employed to investigate the elasticity of tissue, particularly in Schlemm's canal. This study aims to analyzed the morphological parameters of Schlemm's canal among patients with POAG and normal healthy control. In this observational study, we included one hundred patients, among them 50 patients had POAG, and 50 healthy controls, and both eyes were assessed. We measured the study cohort's and the healthy cohort's eyes' elevated IOP and the Schlemm's canal cross-sectional area (CSA). RT-Vue OCT was used to analyze both eyes' temporal, superior, inferior, and nasal regions. The data were analyzed using both univariate and bivariate methods. The characteristics of the morphological measurement of Schlemm's canal results were similar to those of Kagemann et al. There was a significant difference between age and SC measurement, but no correlation was observed between SC measurement and IOP or visual acuity. OCT is a useful way to evaluate the morphological status of Schlemm Canal in glaucoma patients. The eyes with POAG had smaller Schlemm's Canal- CSA than the normal eyes. The Schlemm canal-CSA in Chinese people had no differences from that of peoples of other races.

Design and Manufacture of 30-Degree Projection Lens for Augmented Reality Waveguide.

A projection lens with a 30-degree field of view is developed for use in augmented reality (AR) glasses, including a waveguide combiner designed for a 0.35-inch LCoS panel. The entrance pupil diameter of the lens is 14 mm and the lens has an effective focal length of 16.443 mm; an F-number of 1.175. This paper has four key issues: optical projection lens design, lens manufacturing and assembly tolerance analysis, projection lens resolution testing, and AR glasses system resolution testing of panel images projected by the projection lens. After lens manufacture, the lens was tested, achieving a central field image quality of 57 cycles/mm, an angular resolution of 33 pixels per degree (PPD), a 0.7 field image quality of 40.3 cycles/mm, and an angular resolution of 23 pixels per degree (PPD). Imaging performance testing based on a diffraction-type waveguide shows a resolution of 57 cycles/mm in the center area and an angular resolution of 33 PPD.

An application of recurrence relations to central force fields

By generalizing the relationships between auxiliary variables that appear in the works of A.E. Roy, we investigate the dynamics of non-interacting particles under the action of a central force field whose force function is a solution to a certain differential equation. The method used by A.E. Roy, R. Broucke, and later by G. Sitarski, was utilized in such a way that the obtained recursive equations can be used to describe the motion of a particle under such a field. The class of such fields includes both gravitational and non-gravitational force fields. Several numerical and historically essential examples and detailed discussions of various cases are given.