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In 1970s we analyzed the neutron monitor (NM) and muon telescope (MT) data from the global network for 1966-1970 to determine the amplitude and phase of the significant harmonics constituting the galactic cosmic ray (GCR) daily anisotropy in solar time. The median rigidity of response (Rm) of detectors to GCR spectrum covered a wide range (16-134 GV). The results were reported at the international cosmic ray conferences (ICRCs) held at Denver [1973], Munich [1975] and Paris [1981]. It was inferred that GCR solar daily anisotropy consists of only three harmonics, namely the diurnal (1 cpd, first harmonic), the semidiurnal (2 cpd, second harmonic) and the tridiurnal (3 cpd, third harmonic), with power spectral densities in the ratio 800:20:1 for the Deep River NM data (Rm = 16 GV) for 1962-1971. The fourth harmonic (4 cpd) was absent in these analyses. Since then the volume of data from the global network of NMs and MTs has increased significantly; particularly the multidirectional MT network, with larger Rm values. This motivates us to ascertain whether 4 cpd peak is absent in the cosmic ray solar daily variation data at the global sites, over a longer time period (1963-2015). Our informed conjecture is that 4 cpd peak is insignificant at 2σ-level of experimental error for a range of Rm values (11-60 GV). The discovery of a physically significant fourth harmonic would challenge the theorists to come up with a model for GCR transport in the heliosphere revealing hitherto unknown feature(s) of solar modulation. [ABSTRACT FROM AUTHOR]

Recently Clette et al. (Space Sci. Rev. 186, 35, 2014) completed the first revision of the international sunspot number SSN(V2) since its creation by Wolf in 1849 SSN(V1) starting in 1700 and ending in May 2015. The yearly values of SSN(V2) are larger than those of SSN(V1) but the secular trend in their timelines both exhibit a gradual descent after Cycle 21 minimum resulting in greatly reduced activity for Cycle 24. It has two peaks; one in 2012 due to activity in the north hemisphere (NH) and the other in 2014 due to excess activity in the south hemisphere (SH). The N-S excess of hemispheric SSNs is examined for 1950 - 2014, in relation to the time variations of the solar polar field for 1976 - 2015, covering five complete solar cycles (19 - 23) and parts of the bordering two (18, 24). We find that SH tends to become progressively more active in the declining phase of the cycles reaching an extreme value that gave rise to a second higher peak in October 2014 in the smoothed SSNs accompanied by a strong solar polar field in SH. There may be a Gleissberg cyclicity in the asymmetric solar dynamo operation. The continuing descent of the secular trend in SSNs implies that we may be near a Dalton-level grand minimum. The low activity spell may last well past 2060, accompanied by a stable but reduced level of the space weather/climate. Fourier spectrum of the time domain of SSNs shows no evidence of the 208 year/cycle (ypc) (DeVries/Suess cycle) seen in the cosmogenic radionuclide ( ${}^{10}\mathrm{Be}$ ) concentration in the polar ice cores and ${}^{14}\mathrm{C}$ record in trees indicating that 208 ypc peak may be of non-solar origin. It may arise from the climate process(es) that change(s) the way radionuclides are deposited on polar ice. It should be noted that we only have ${\sim}\,400~\mbox{years}$ of SSN data, so it is possible that DeVries/Suess cycle is really driven by the Sun but for now we do not have any evidence of that; there is no known physical process linking 208 ypc to solar dynamo operation. [ABSTRACT FROM AUTHOR]

Galactic cosmic-ray (GCR) modulation at 1 AU for sunspot (SSN) Cycle 24 is studied using data from a global network of detectors and balloon measurements of low-energy ions at high latitudes in Russia. The observed modulation is modest compared with previous cycles. The tilt angle of the heliospheric current sheet reached a maximum value for Cycle 24 even though the peak of the interplanetary magnetic-field intensity at 1 AU has a much lower value (≈ 5 nT). The solar polar field in the northern hemisphere reversed in June 2012 and again in March 2014 while that in the southern hemisphere reversed in July 2013. The double field reversal in northern hemisphere after SSN maximum is not expected from dynamo theory. GCR modulation is at maximum phase in 2013. We have also studied the anomalous GCR recovery in 2009 using data from a low-energy proton channel on Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics (PAMELA). The rigidity dependence of the Cycle 24 modulation is computed using data from neutron monitors, directional muon telescopes at Nagoya, Japan, and detectors on balloons at high latitudes in Russia. It is a power law with an exponent −1.29, similar to previous solar cycles (−1.2±0.1); the nearly linear dependence of the modulation on the rigidity over a wide range poses a challenge to the quasi-linear theory (QLT) of GCR modulation. [ABSTRACT FROM AUTHOR]

The pressure corrected hourly data from the global network of cosmic ray detectors, measurements of the interplanetary magnetic field (IMF) intensity ( B) at Earth's orbit and its components B, B, B (in the geocentric solar ecliptic coordinates) are used to conduct a comprehensive study of the galactic cosmic ray (GCR) intensity fluctuations caused by the halo coronal mass ejection of 13 May 2005. Distinct differences exist in GCR timelines recorded by neutron monitors (NMs) and multidirectional muon telescopes (MTs), the latter respond to the high rigidity portion of the GCR differential rigidity spectrum. The Forbush decrease (FD) onset in MTs is delayed (∼5 h) with respect to the onset of a geomagnetic storm sudden commencement (SSC) and a large pre-increase is present in MT data before, during, and after the SSC onset, of unknown origin. The rigidity spectrum, for a range of GCR rigidities (≤200 GV), is a power law in rigidity (R) with a negative exponent ( γ=−1.05) at GCR minimum intensity, leading us to infer that the quasi-linear theory of modulation is inconsistent with observations at high rigidities (>1 GV); the results support the force field theory of modulation. At present, we do not have a comprehensive model for the FD explaining quantitatively all the observational features but we present a preliminary model listing physical processes that may contribute to a FD timeline. We explored the connections between different phases of the FD and the power spectra of IMF components but did not find a sustained relationship. [ABSTRACT FROM AUTHOR]

Ahluwalia and Jackiewicz (2011) have predicted that sunspot cycle 24 will be only half as active as cycle 23, reaching its peak in May 2013 ±6 months. Here, we discuss the timeline for cycle 24 since its onset in December, 2008 and compare it to the timelines for the last ten cycles (14 to 23) of the 20th century; cycle 24 is rising the slowest. We speculate that cycle 24 may herald the onset of a Dalton-like minimum in the 21st century. The implications of this outcome on global temperature change and ensuing socioeconomic and political scenarios are discussed, on the basis of the historical record. [ABSTRACT FROM AUTHOR]

Eye (2003) 17, 263-266. doi:10.1038/sj.eye.6700243 [ABSTRACT FROM AUTHOR]

A letter to the editor by Y. K. Ghosh, H. Ahluwalia and J. Beamer is presented outlining the use of povidone-iodine as anesthesia before ophthalmic surgery in vol. 61 of the 2006 issue.

Presents news briefs from within the medical field. Burden that junk foods put on healthcare systems; Effects of stress on health; Late effects of whiplash injuries.

Purpose: To report two cases of the rare complication of entropion following involutional ptosis surgery and its successful management. Methods: Clinical findings and management of the patients are presented. Results: Case 1: An 89-year-old female underwent aponeurosis advancement surgery for left involutional ptosis. Post-operatively she achieved good lid height, but had developed entropion of the upper lid which resulted in a persistent corneal epithelial defect. The patient underwent repeat surgery during which the aponeurosis was found to be inserted into the lower part of middle one third of tarsus with the tarsus itself being extremely thin. The aponeurosis was reinserted into upper third of tarsus, followed by greyline split with anterior lamellar repositioning. Post-operatively the patient achieved good lid height with correction of the entropion.Case 2: A 70-year-old male who had previously undergone bilateral brow lift and ptosis correction two years ago, was referred with right upper lid entropion. During surgery the aponeurosis was found to be inserted into the lower part of middle one third of tarsus, with a very thin tarsus. This patient was also managed by reinserting aponeurosis into upper third of tarsus with grey line split and anterior lamellar repositioning following which he achieved good lid height and correction of the entropion. Comment:Entropion has rarely been reported as a complication of ptosis surgery. This case series highlights the importance of taking special care when advancing the aponeurosis, in cases where the tarsus is thin, as it may result in vertical buckling of the tarsus. [ABSTRACT FROM AUTHOR]

This article focuses on side-effects due to increasing use of the anti-impotency drug viagra or sildenafil citrate. It presents a case of visual loss that took place within 12 hour of intake of the drug. A 61-year-old taxi driver presented to the eye casualty with a 12-h history of loss of vision in his right eye following consumption of double his normal dose of Viagra (100mg). He was a high hypermetrope with an amblyopic left eye. Examination revealed Snellen acuity of counting fingers in the right eye and 6/12 in his amblyopic left eye. It was encouraging to see his visual acuity improve steadily with resolution of headaches.

Purpose: To review cases of possible drug-induced ectropion and recommend what we consider to be best practice. Design: Retrospective observational case series. Participants: Thirteen consecutive outpatients. Methods: Records of 13 outpatients on topical medication presenting with topical drug-induced ectropion were retrospectively analyzed. Main Outcome Measures: Eyelid position, topical agent causing the allergy, and medical and surgical management options. Results: In all 13 patients, the ectropion resolved partially or completely after discontinuing the offending topical agent. Dorzolamide (53%) was the most common offending agent, followed by brimonidine (23%). One of the 13 patients underwent failed ectropion surgery correction before referral, but improved once the topical agent was discontinued. Two of the patients successfully underwent surgical correction for ectropion after discontinuing their topical therapy. Those patients who discontinued the topical therapy and had a short course of steroid therapy did not require surgical correction. Conclusions: This study demonstrates that sensitivity to topical agents can induce ectropion in more than 1 manner. Chronic exposure to the causative agent leads to cicatricial changes in the anterior lamella of the eyelid in susceptible individuals, and can manifest as contact dermatitis leading to tissue edema and mechanical ectropion. Early recognition of this condition and discontinuation of therapy is of paramount importance; it may lead to complete resolution. Topical steroids are a necessary adjunct in the management of drug-induced ectropion. Based on our experience, we propose a management algorithm for drug-induced ectropion. [Copyright &y& Elsevier]

Objective:To report three cases illustrating that it is not unusual for a primary eyelid tumour to metastasise to the parotid gland and vice versa.Case reports:Two patients with malignant parotid tumours underwent radical parotidectomy and presented subsequently with eyelid lesions. Biopsy showed that both eyelid lesions were histologically similar to the primary parotid tumour. A third patient was noted to have ipsilateral upper eyelid and parotid gland tumours. Histology and immunocytochemistry were used to differentiate the primary tumour and the metastasis.Conclusion:These cases illustrate that tumours involving eyelids and parotid glands can present simultaneously or sequentially, and either of these structures could be the focus of primary or metastatic tumour. The important message for oculoplastic and parotid surgeons is to routinely assess both the periocular and parotid area when patients present with a mass in either structure. [ABSTRACT FROM PUBLISHER]

The article presents a case study of a 68-year-old man with a history of strabismus surgery for left-eye merging squint correction and was diagnosed with orbital cyst after hospital admission. Both eyes visual acuity, left osotropia and left eye abduction restriction were also identified through a detailed ocular examination. Magnetic resonance imaging (MRI) was also conducted to the patient for further examination. It concludes that orbital cysts are a complexity of strabismus surgery.