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Objective: To evaluate the effects of menopause and hormone replacement therapy (HRT) on the quality and amount of tear, intraocular pressure (IOP) and retrobulbar blood flow velocities. Patients and Methods: Twenty women aged between 40 and 50 years, free of ocular and systemic diseases and planning to receive HRT were recruited as the study group. Twenty-four healthy, age-matched but still menstruating women were enrolled as controls. On the first day of study basal and reflex Schirmer test, tear break-up time and IOP measurements (at 08.00, 12.00 and 16.00 h) were performed for all groups. On the second day of the study, the peak systolic velocity (PSV), end diastolic velocity (EDV) and resistivity index (RI) of the ophthalmic (OA), central retinal (CRA), nasal (NSPCA) and temporal short posterior ciliary (TSPCA) arteries were determined by color Doppler imaging. The menopausal group received HRT for 2 months, when all measurements were repeated for the 15 women who had received HRT on a daily basis. Results: The quality and amount of tear decreased (p < 0.01), IOP (p < 0.01) and RI of the CRA, TPCA and NPCA (p < 0.05) increased in postmenopausal women compared with the control group. After 2 months of HRT, the quality and amount of tear had increased (p < 0.001) and the IOP had decreased (p < 0.001). The PSV of the CRA and TSPCA had decreased (p < 0.05), as had the RI in the CRA (p < 0.001), NSPCA and TSPCA (p < 0.05). Conclusion: We conclude that age-induced changes on quality and amount of tear, IOP and retrobulbar blood flow are intensified by the menopause and that it may be possible to decrease the menopausal effects on these parameters by HRT.

These findings indicate that adolescence may be a more appropriate time to intervene for PCOS patients, as many cardiovascular risks are already present during early adulthood. As far as IMT is concerned, mechanisms other than hyperandrogenaemia and obesity might be operating as causative factors.

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Dispersive shock waves (DSWs) in the Kadomtsev-Petviashvili (KP) equation and two dimensional Benjamin-Ono (2DBO) equation are considered using parabolic front initial data. Employing a front tracking type ansatz exactly reduces the study of DSWs in two space one time (2 + 1) dimensions to finding DSW solutions of (1 + 1) dimensional equations. With this ansatz, the KP and 2DBO equations can be exactly reduced to cylindrical Korteweg-de Vries (cKdV) and cylindrical Benjamin-Ono (cBO) equations, respectively. Whitham modulation equations which describe DSW evolution in the cKdV and cBO equations are derived in general and Riemann type variables are introduced. DSWs obtained from the numerical solutions of the corresponding Whitham systems and direct numerical simulations of the cKdV and cBO equations are compared with excellent agreement obtained. In turn, DSWs obtained from direct numerical simulations of the KP and 2DBO equations are compared with the cKdV and cBO equations, again with remarkable agreement. It is concluded that the (2 + 1) DSW behavior along parabolic fronts can be effectively described by the DSW solutions of the reduced (1 + 1) dimensional equations.