Random assignments with uniform preferences: An impossibility result

Agents have uniform preferences if a weakly decreasing utility function determines each agent's preference ranking over the same order of alternatives. We show that the impossibility in the random assignment problem between strategyproofness, ordinally efficiency, and fairness in the sense of equal division lower bound, prevails even if agents have uniform preferences. Furthermore, it continues to hold even if we weaken the strategyproofness to upper-contour strategyproofness, or the ordinal efficiency to robust ex-post Pareto efficiency

Unusual Subcutaneous Presentation of Cavernous Hemangioma in the Lower Eyelid: A complete translation from Farsi

This article is based on a study first reported in Farsi in the Bina Journal of Ophthalmology, titled معرفی یک مورد همانژیوم کاورنوس پلک تحتانی, Volume 23, Issue 2 (Winter 2018) 2018/10/23. Original URL: https://binajournal.org/article-1-936-fa.pdf Purpose: To report a patient with cavernous hemangioma (CH) presenting as a “subcutaneous” lower eyelid mass. Case report: A 37-year-old man presented with a painless and palpable mass over the right lower eyelid for two years prior to referral. Computed tomography scan revealed a well-defined, lobulated mass located in the mid and lateral portion of the lower eyelid that extended posteriorly to the anterior orbital space. A transcutaneous excisional biopsy was performed. Histopathologic findings of the tumor confirmed CH. Most CHs are intraconal lesions, making our case an unusual presentation for this condition. Conclusion: CH may present superficially in the eyelid and anterior orbital area and thus, although this location is not common, it should be kept in mind as a differential diagnosis for any well-defined eyelid tumor

Neuro-ophthalmic Manifestations of Coronavirus Disease 2019 and Its Vaccination: A Narrative Review

Coronavirus disease 2019 (COVID-19) is a current pandemic caused by SARS-CoV-2 that has vastly affected the whole world. Although respiratory disease is the most common manifestation of COVID-19, the virus can affect multiple organs. Neurotropic aspects of the virus are increasingly unfolding, in so far as some respiratory failures are attributed to brainstem involvement. The neuro-ophthalmic manifestations of COVID-19 and the neuro-ophthalmic side effects of vaccination were reviewed. The major findings are that the SARS-CoV-2 infection commonly causes headaches and ocular pain. It can affect the afferent and efferent visual pathways by ischemic or inflammatory mechanisms. Optic nerve may be the origin of transient or permanent visual loss from papillophlebitis, idiopathic intracranial hypertension, or optic neuritis. Cerebrovascular strokes are not uncommon and may lead to cortical visual impairment or optic nerve infarction. SARSCoV- 2 may affect the pupillomotor pathways, resulting in tonic pupil (Adie’s syndrome) or Horner’s syndrome. Cranial neuropathies including third, fourth, sixth, and seventh nerve palsies have all been reported. Rhino-orbital mucormycosis superinfections in COVID-19 patients receiving steroids or other immunosuppressive therapies may result in unilateral or bilateral visual loss and ophthalmoplegia. Autoimmune conditions such as Guillain- Barré, Miller-Fisher syndrome, and ocular myasthenia have been reported

Antarctic Time-Variable Regional Gravity Field Model Derived from Satellite Line-of-Sight Gravity Differences and Spherical Cap Harmonic Analysis

This study focuses on the development of a time-variable regional geo-potential model for Antarctica using the spherical cap harmonic analysis (SCHA) basis functions. The model is derived from line-of-sight gravity difference (LGD) measurements obtained from the GRACE-Follow-On (GFO) mission. The solution of a Laplace equation for the boundary values over a spherical cap is used to expand the geo-potential coefficients in terms of Legendre functions with a real degree and integer order suitable for regional modelling, which is used to constrain the geo-potential coefficients using LGD measurements. To validate the performance of the SCHA, it is first utilized with LGD data derived from a L2 JPL (Level 2 product of the Jet Propulsion Laboratory). The obtained LGD data are used to compute the local geo-potential model up to Kmax = 20, corresponding to the SH degree and order up to 60. The comparison of the radial gravity on the Earth’s surface map across Antarctica with the corresponding radial gravity components of the L2 JPL is carried out using local geo-potential coefficients. The results of this comparison provide evidence that these basis functions for Kmax = 20 are valid across the entirety of Antarctica. Subsequently, the analysis proceeds using LGD data obtained from the Level 1B product of GFO by transforming these LGD data into the SCHA coordinate system and applying them to constrain the SCHA harmonic coefficients up to Kmax = 20. In this case, several independent LGD profiles along the trajectories of the satellites are devised to verify the accuracy of the local model. These LGD profiles are not employed in the inverse problem of determining harmonic coefficients. The results indicate that using regional harmonic basis functions, specifically spherical cap harmonic analysis (SCHA) functions, leads to a close estimation of LGD compared to the L2 JPL. The regional harmonic basis function exhibits a root mean square error (RMSE) of 3.71 × 10−4 mGal. This represents a substantial improvement over the RMSE of the L2 JPL, which is 6.36 × 10−4 mGal. Thus, it can be concluded that the use of local geo-potential coefficients obtained from SCHA is a reliable method for extracting nearly the full gravitational signal within a spherical cap region, after validation of this method. The SCHA model provides significant realistic information as it addresses the mass gain and loss across various regions in Antarctica

Globalization and the outbreak of COVID-19 : an empirical analysis

The purpose of this study is to examine the relationship between the extension of globalization and coronavirus disease 2019 (COVID-19) case fatality rate (CFR) calculated on 28 July 2020 in more than 150 countries. Our regression analyses show that countries with higher levels of socio-economic globalization are exposed to higher levels of CFR. The positive association between the level of globalization of countries and their COVID-19 fatality rate remains robust, controlling for cross-country differences in economic development and demographics, health care costs, health care capacity, quality of governance and continental dummies

Aspheric versus Spherical Posterior Chamber Intraocular Lenses

Purpose: To compare spherical aberration and contrast sensitivity function following implantation of four different foldable posterior chamber intraocular lenses (IOLs), namely Sensar, Akreos AO, Tecnis, and AcrySof IQ. Methods: In this randomized clinical trial, 68 eyes of 68 patients with senile cataracts underwent phacoemulsification and IOL implantation with Sensar (n=17), Akreos AO (n=17), Tecnis (n=17), or AcrySof IQ (n=17). Uncorrected visual acuity (UCVA) and best spectacle-corrected visual acuity (BSCVA), spherical aberration and contrast sensitivity function (CSF) were compared among the study groups, 3 months after surgery. Results: There was no significant difference between the study groups in terms of age (P = 0.21). Mean postoperative BSCVA with Sensar, Akreos AO, Tecnis, and AcrySof IQ was 0.15±0.10, 0.12±0.9, 0.08±0.08, and 0.08±0.07 logMAR, respectively (P=0.08). Spherical aberration measured over a 4 mm pupil was significantly higher with Sensar and Akreos AO than the two other IOLs. The difference between Tecnis and AcrySof IQ was significantly in favor of the former IOL. Over a 6 mm pupil, spherical aberrations were comparable with Sensar and Akreos AO, furthermore spherical aberration was also comparable among eyes implanted with Akreos AO, AcrySof IQ, and Tecnis. Sensar yielded significantly inferior results as compared to Acrysof IQ and Tecnis. CSF with Sensar was inferior to the three aspheric IOLs at the majority of spatial frequencies. Tecnis yielded significantly better mesopic CSF at 1.5 and 3 cycles per degree spatial frequencies. Conclusion: Tecnis and AcrySof IQ provided significantly better visual function as compared to Sensar and Akreos AO, especially with smaller pupil size. However, this difference diminished with increasing pupil size

Choroidal Thickness in Acute Non-arteritic Anterior Ischemic Optic Neuropathy

Purpose: To compare the choroidal thickness in eyes with acute non-arteritic anterior ischemic optic neuropathy (NAION) with healthy contralateral eye and normal controls. Methods: Thirty-eight eyes with NAION, thirty-eight unaffected fellow eyes, and seventy four eyes from 37 healthy, age- and sex-matched subjects were included in this prospective comparative case-control study. Choroidal thickness was measured by enhanced depth imaging (EDI) of spectral domain optical coherence tomography (SDOCT). Peripapillary choroidal thickness (PCT) was measured at 1000 and 1500 μm from Bruch's membrane opening (BMO). Subfoveal choroidal thickness (SFCT) was measured in central subfoveal area, and 500 microns apart in temporal and nasal sides. Choroidal thickness among NAION eyes, uninvolved fellow eyes, and control eyes were compared. Results: The mean of PCT at 1000 μm was significantly thicker in NAION and fellow eyes compared to control eyes (169.7 ± 47, 154.4 ± 42.1, and 127.7 ± 49.9 μm, respectively, P < 0.001 and P = 0.42). The mean PCT at 1500 μm was also significantly thicker in NAION and fellow eyes compared to control eyes (178.6 ± 52.8, 162.6 ± 46.1, and 135.1 ± 59 μm, respectively, P = 0.007 and P = 0.048). The mean PCT at 1000 and 1500 μm was significantly greater in NAION compared to fellow eyes (P = 0.027 and P = 0.035, respectively). The mean of SFCT was significantly thicker in NAION compared to control eyes (P = 0.032); however, there was no significant difference between uninvolved fellow and control eyes (P = 0.248). Conclusion: Thicker choroidal thickness in acute NAION and uninvolved fellow eyes compared to normal eyes suggests a primary choroidal role in NAION pathophysiology

Discontinuous rock slope stability analysis under blocky structural sliding by fuzzy key-block analysis method

This study presents a fuzzy logical decision-making algorithm based on block theory to effectively determine discontinuous rock slope reliability under various wedge and planar slip scenarios. The algorithm was developed to provide rapid response operations without the need for extensive quantitative stability evaluations based on the rock slope sustainability ratio. The fuzzy key-block analysis method utilises a weighted rational decision (multi-criteria decision-making) function to prepare the 'degree of reliability (degree of stability-instability contingency)' for slopes as implemented through the Mathematica software package. The central and analyst core of the proposed algorithm is provided as based on discontinuity network geometrical uncertainties and hierarchical decision-making. This algorithm uses block theory principles to proceed to rock block classification, movable blocks and key-block identifications under ambiguous terms which investigates the sustainability ratio with accurate, quick and appropriate decisions especially for novice engineers in the context of discontinuous rock slope stability analysis. The method with very high precision and speed has particular matches with the existing procedures and has the potential to be utilised as a continuous decision-making system for discrete parameters and to minimise the need to apply common practises. In order to justify the algorithm, a number of discontinuous rock mass slopes were considered as examples. In addition, the SWedge, RocPlane softwares and expert assignments (25-member specialist team) were utilised for verification of the applied algorithm which led to a conclusion that the algorithm was successful in providing rational decision-making

SURVEYING THE RELATIONSHIP BETWEEN INDIVIDUAL FACTORS AND WITHDRAWAL BEHAVIORS OF EMPLOYEES AT THAMEN AL- AEMEH CREDIT COOPERATIVE IN KHUZESTAN

Abstract The study has been done in order to determine the relationship between individual factors (work stress, job satisfaction, work motivation, work trust, procedural justice) as independent variables and withdrawal behaviors (physical withdrawal and psychological withdrawal) as dependent variable. The population was 300 employees of Thamen Al-Aemeh credit cooperative in Khuzestan. We determined the amount of the sample size with the used of Cochran sampling method which the statistical sample is 141 of these employees which have been selected through the simple random sampling method. To gathering of data, we used questionnaire. Questionnaires reliability was estimated by calculating Cronbach's Alpha. In order to analyze the data resulted from collected questionnaires deductive and descriptive statistical methods are used. The results Kolmogorov-Smirnov Test shows the test distribution is Normal. So we can use Pearson Correlation coefficients to test the hypothesis of the research. In order to determine the relationship between the variables of the study, the SPSS tool has been used. The results of hypotheses shows that individual factors (job satisfaction, work motivation, work trust, procedural justice) have a negative significant correlation with physical and psychological withdrawal at Thamen Al-Aemeh credit cooperative in Khuzestan. But work stress has a positive correlation with physical and psychological withdrawal. Finally, we can say that there is negative significant relationship between individual factors and withdrawal behaviors at Thamen AlAemeh credit cooperative in Khuzestan