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Alexandre Matet,1,2 Nawel Amar,1,2 Saddek Mohand-Said,1–4 José-Alain Sahel,1–7 Pierre-Olivier Barale1,2 1INSERM and DHOS, CHNO des Quinze-Vingts, 2Sorbonne Universités, UPMC Univ Paris 6, Institut de la Vision, 3INSERM, 4CNRS, Paris, France; 5Institute of Ophthalmology, University College London, London, UK; 6Fondation Ophtalmologique Adolphe de Rothschild, 7Académie des Sciences, Institut de France, Paris, France Introduction: The Argus II retinal prosthesis is composed of an epiretinal electrode array positioned over the macula and connected to an extrascleral electronics case via a silicone cable, running through a sclerotomy. During implantation, the manufacturer recommends to cover the sclerotomy site with a patch of processed human pericardium to prevent postoperative hypotony and conjunctival erosion by the underlying electronics case. Due to biomedical regulations prohibiting the use of this material in France, we developed an alternative technique combining a scleral flap protecting the sclerotomy and an autogenous graft of superior temporalis fascia overlying the electronics case. Methods: The purpose of this study is to describe the 4-year outcomes of this modified procedure in three subjects who underwent Argus II Retinal Prosthesis System implantation. Clinical data consisting of intraocular pressure measurements and tolerance in terms of conjunctival erosion or inflammation were retrospectively assessed over a 4-year postoperative follow-up. Results: None of the three patients implanted with the modified technique developed ocular hypotony over 4 years. A normal, transient conjunctival inflammation occurred during the first postoperative month but conjunctival erosion was not observed in any of the three patients over 4 years. Four years after implantation, the autogenous temporalis fascia graft remained well tolerated and the retinal prosthesis was functional in all three patients. Conclusion: The combination of an autograft of superficial temporalis fascia and a scleral flap efficiently prevented leakage through the sclerotomy site, ocular hypotony, and conjunctival erosion by the extrascleral electronics case. This modified technique is suitable for the implantation of existing and forthcoming retinal prostheses. Superficial temporalis fascia may also be used as alternative to commercial tectonic tissues for scleral wound repair in clinical settings where they are not available. Keywords: visual prosthesis, retinitis pigmentosa, surgical procedure, conjunctiva, intraocular pressure

Today, one of the most important issues in mobile communication systems is having a long battery life. Therefore, the problem of power consumption appears as one of the challenges in the field of designing high frequency circuits. In a high-frequency receiver, due to the placement of the low-noise amplifier in the first stage of the receiver, this amplifier is very important to determine the linearity and noise in the entire receiver. In this paper, a low noise amplifier has been designed for the GPS standard. Compared to previous works, the noise of the amplifier has been reduced somehow, and its power consumption has reached its minimum value. The working method is that in common source amplifiers, their source base is connected with an inductor, which results in improving circuit noise. But the used inductor occupies the surface of the chip. Therefore, in this article, the existence of the inductor in wire-bond is used, and the noise of the amplifier is reduced, and the occupied area of the chip is not increased. Gain, NF, input impedance of the proposed amplifier have been calculated in the best case and the worst case in the corners of FF and SS, and it can be seen that in this article, compared to the previous works, very favorable results have been obtained.

Photon crystals are on of the most common structures for designing and implementing electronic optical circuits. The photon gap band is of great importance in these structures. The most common mathematical methods for analyzing and calculating photon band diagrams and extracting the forbidden photon band of photon crystals is the flat wave expansion method. This method has many complexities that require special commercial software to perform its calculations. In two-dimensional photonic crystals, two parameters in the photon band are affected, which are the refractive index of the dielectric material and the ratio of the radius of the holes to the constant of the crystal lattice (r / a). In this paper, using mathematics and linear regression, simpler relations for extracting the photon band range of photon crystals are presented. Comparison of the results obtained from the relations with the results obtained with BandSOLVE software for photonic crystals shows that the maximum difference between the two calculation methods for fl and fu is 0.007 and 0.028, respectively, and the average difference is , respectively 0.004 and is 0.01.

Abstract Objective: The cardioprotective effects of nuts are well established. However, the positive impacts of nuts in preventing CVD at a younger age, a condition known as premature coronary artery disease (PCAD), is still debated. Therefore, we aim to determine the association between nuts and PCAD occurrence and its severity in different Iranian ethnicities. Design: This case–control study was conducted within the framework of the Iran-premature coronary artery disease (I-PAD) study, an ongoing multi-centric study on Iranian patients of different ethnicities. Setting: This multi-centric case–control study was conducted in among 3253 persons under the age of 70 years in women and 60 years in men from different ethnicities in Iran. Participants: Information on nut consumption was collected using a validated FFQ. Subjects were selected from among the candidates for angiography. Cases were those whose coronary angiography showed stenosis of more than 75 % in at least one vessel or more than 50 % of the left main artery, while the control group participants had normal angiography results. Results: In the crude model, compared to the first quartile, the highest quartile of nut consumption was significantly associated with a lower risk of PCAD (OR = 0·26, 95 % CI (0·21, 0·32); P for trend = 0·001). In the top quartile of nut intake, a substantial decrease in PCAD was observed after controlling for putative confounders (OR = 0·32; 95 % CI (0·24, 0·43); P for trend = 0·001). Additionally, a 75 % decrease in the risk of severe PCAD was observed in the participants in the highest quartile of nut intake. Conclusion: A significant inverse association was observed between nut intake and the risk and severity of PCAD in the Iranian population. Large-scale clinical trials are required to confirm these findings.

An all optical multiplexer will be implemented.Two nonlinear ring resonators with different switchingthresholds will be utilized for creating the proposedmultiplexer. The proposed structure will have two inputand one output port. A control port will be utilized todecide which input data can be illustrated at the outputport. The rise time for the proposed structure is about 2ps. The proposed device can be utilized for implementingall optical systems and networks.

Introduction: Early clinical exposure is a learning strategy, which can expose medical students during their first year of education with clinical environment. In view of this, this study has been carried out a different kind of early clinical exposure to practice medical professionalism. Methods: This study was a development study that was conducted in the academic years 2017-2018. Initially, needs assessment was performed based on literature review and expert panel. Then, the design of early exposure was depicted through a focus-group interview with the presence of Olympiad students. After that, the program was implemented. The topics were presented individually in the workshop and audio podcasts were presented in the Learning Management System. In the second practical round, namely early clinical exposure, the students were divided into multiple groups and practiced communication skills and professionalism in the clinical contexts by a tutor who was in higher level of education. To evaluate this program, satisfaction forms were employed to assess the students' learning through multiple-choice and descriptive tests. Results: In the evaluation, great level of the students' satisfaction was about the selected environments, the educational program (78.1%), the employed methods of the course (73.2%) and recognition of professional responsibilities (73.2%). The least level of the students' satisfaction was the amount of learning opportunities (65.8%). 75.6% of students acknowledged the increase in their professionalism. Conclusion: Early clinical exposure is a rich opportunity for enhancing professionalism and communication skills for medical students who are in the introductory level of medical education. This way, repeating the outcomes of this study in experimental and clinical trials is recommended. Early clinical exposure should be followed seriously for long-term as well.

Background: The Isfahan COVID Cohort (ICC) study was designed to investigate the short- and long-term consequences of patients with COVID-19 in Iran. This report presents the rationale, methodology, and initial results of ICC. Materials and Methods: ICC is a 5-year multicentric prospective cohort study that is ongoing on two groups including 5000 patients hospitalized with moderate or severe and 800 nonhospitalized patients with mild or asymptomatic COVID-19 in Isfahan. The ICC endpoints are morbidity, mortality, incident cases, or worsening of underlying noncommunicable diseases (NCDs) and their risk factors. In the current analysis, we examined the persistent symptoms and incident NCDs or risk factors in 819 previously hospitalized patients who completed 1-year follow-up. Results: The two most common symptoms were joint pain/myalgia (19.7%) and dry cough/dyspnea (18.7%). Around 60% of patients had at least one symptom which was more common among women than men and in middle aged than younger or older patients. Female (odds ratio [OR] =1.88, 95% confidence interval [CI]: 1.39–2.55) and highly-educated patients (OR = 2.18, 95% CI: 1.56–3.04) had higher risk of having any symptom in 1-year follow-up. New cases of hypertension followed by diabetes then coronary heart disease (CHD) were the most common incident NCDs. Conclusion: During 1-year follow-up after hospital discharge, about 60% of patients experienced persistent symptoms. Incident hypertension, diabetes, and CHD were the most common events seen. Close monitoring and extensive health services with integrative approaches are needed to improve the health status of these patients.

BACKGROUND: Hypertension (HTN) is one of the most common non-communicable diseases (NCDs), which in 2017 accounted for 1.65% of all deaths, and 0.66% of disability-adjusted life years (DALYs). About 25% of the adult population are hypertensive in Iran. Prevalence of HTN is significantly higher in those with a family history of HTN. This study compares the impact of paternal and maternal history of HTN on the risk of HTN development.METHODS: This cross-sectional study was conducted among 2107 adults of 18-84 years old residing in Isfahan, Iran, from August 2015 to March 2016. Blood pressure (BP) measurement standards were taken from World Health Organization (WHO) guidelines. We measured BP in the right arm for three times at 1-minute intervals and considered the mean of second and third measurements. Other data were collected by questionnaire.RESULTS: Prevalence of HTN was higher in participants whose mother or both parents were hypertensive (P < 0.001). Diastolic BP (DBP) was affected by every side of parental history (P < 0.001), while systolic BP(SBP) was affected when both parents were hypertensive (P < 0.001). As a result, maternal family history increased the odds of HTN by 1.9 times [95% confidence interval (CI): 1.35-2.65] and both maternal and paternal history increased it by 3.1 times (95% CI: 2.01-4.78) compared to those with no family history. However, paternal history was not significantly related to the odds of HTN.CONCLUSION: Our study results demonstrate that maternal history of HTN doubles the odds of HTN. Besides, if both parents are hypertensive, it will be tripled.