Influence of COVID-19 pandemic on pregnancy and fertility preferences among the residents of the United Arab Emirates (UAE).

Background: The coronavirus disease 2019 (COVID-19) significantly impacted the lifestyles of millions of people, with new challenges arising as the pandemic progresses. However, little attention has been given to issues like fertility intentions and pregnancy planning during COVID-19. Consequently, we aimed to investigate the influence of the pandemic on pregnancy and fertility decisions among the residents of the United Arab Emirates (UAE). Methods: We surveyed UAE residents of reproductive age between November 2021 to June 2022 via the Google Forms platform and collected data on demographics, associated health conditions, COVID-19 infections, as well as plans for pregnancy and fertility intentions. We presented data through descriptive statistics (frequencies and percentages) and used Pearson's χ2 test to compare the characteristics of participants who reported that the COVID-19 pandemic has influenced their fertility preferences with those who reported that it had not. Results: Overall, 564 participants completed the survey, of whom 115 (20.4%) stated that the COVID-19 pandemic had influenced their fertility preferences. Meanwhile, 234 (41.5%) reported previous history of COVID-19 infection; regarding post-COVID-19 infection symptoms, 53 (22.6%) reported decreased libido and 40 (17%) reported trouble in conceiving a baby. Participants who were ≤30 years of age were less likely to be influenced by the COVID-19 pandemic on their decision on fertility compared to those >30 years of age. Factors like education, income, chronic health conditions, and previous history of COVID-19 infection or vaccination did not have any significant effect on the COVID-19 pandemic influence on fertility preferences. Conclusions: The COVID-19 pandemic has brought in new challenges which could affect fertility and this needs to be studied further for planning effective measures.

Vaccine Side Effects Following COVID-19 Vaccination Among the Residents of the UAE-An Observational Study.

COVID-19 vaccines have proven to be very safe in the clinical trials, however, there is less evidence comparing the safety of these vaccines in real-world settings. Therefore, we aim to investigate the nature and severity of the adverse effects reported and the differences based on the type of vaccine received. A survey was conducted among 1,878 adult (≥18 years) COVID-19 vaccine recipients through online survey platforms and telephonic interviews during March to September 2021. The factors potentially associated with the reported side effects like age, gender, ethnicity, comorbidities, and previous COVID-19 infection were analyzed based on the type of vaccine received. Differences in adverse events and the severity were compared between inactivated and mRNA vaccine recipients. The major adverse effects reported by the COVID-19 vaccine recipients were pain at the site of injection, fatigue and drowsiness, and headache followed by joint/muscle pain. The adverse effects were more common among recipients of mRNA Pfizer-BioNTech vaccine than among recipients of inactive Sinopharm vaccine with the odds ratio of 1.39 (95% CI 1.14-1.68). The average number of adverse effects reported between individuals who had received Sinopharm and Pfizer-BioNTech vaccines was 1.61 ± 2.08 and 2.20 ± 2.58, respectively, and the difference was statistically significant (p <0.001). Severe adverse effects after COVID-19 vaccinations were rare and 95% of the adverse effects reported after either an inactivated or mRNA vaccine were mild requiring no or home-based treatment. The study found that individuals less than 55 years of age, female gender, with history of one or more comorbid conditions, who had received mRNA Pfizer- BioNTech vaccine, and with history of COVID-19 infections are at higher odds of developing an adverse effect post COVID-19 vaccination compared to the others.

Double Brillouin frequency shift through circulation of odd-order Stokes signal.

We demonstrate a simple configuration for generating a double Brillouin frequency shift through the circulation of an odd-order Brillouin Stokes signal. It is operated based on cascaded Brillouin scattering in single-mode optical fibers that behave as the Brillouin gain media. A four-port circulator is incorporated into the setup to circulate the odd-order Brillouin Stokes signal in the fiber. It thus initiates a higher order Brillouin Stokes signal, which is double Brillouin frequency downshifted from the input signal. For the 5 km long fiber, the Brillouin pump power at 23 mW gives a clean output spectrum with 30 dB sideband suppression ratio. The output signal is 0.174 nm or approximately 21.7 GHz downshifted from the input signal.

Contribution of Rayleigh scattering on Brillouin comb line generation in Raman fiber laser.

We demonstrate the generation of multiple Brillouin Stokes lines generation assisted by Rayleigh scattering in Raman fiber laser. The linear cavity is utilized to take advantage of the Rayleigh scattering effect, and it also produces two strong spectral peaks at 1555 and 1565nm. Under a strong pumping condition, the Rayleigh backscatters contribute to the oscillation efficiency, which increases the Brillouin Stokes lines intensity between these two wavelength ranges. The multiple Stokes lines get stronger by suppressing the buildup of free-running longitudinal modes in the laser structure.

Investigation on the effect of EDFA location in ring cavity Brillouin-Erbium fiber laser.

We have investigated the characteristics of Brillouin-Erbium fiber laser (BEFL) with variation of Erbium-doped fiber amplifier (EDFA) locations in a ring cavity configuration. Three possible locations of the EDFA in the laser cavity have been studied. The experimental results show that the location of EDFA plays vital role in determining the output power and the tuning range. Besides the Erbium gain, Brillouin gain also contributes to the performance of the BEFL. By placing the EDFA next to the Brillouin gain medium (dispersion compensating fiber), the Brillouin pump signal is amplified thereby generating higher intensities of Brillouin Stokes line. This efficient process suppresses the free running self-lasing cavity modes from oscillating in cavity as a result of higher Stokes laser power and thus provide a wider tuning range. At the injected Brillouin pump power of 1.6 mW and the maximum 1480 nm pump power of 135 mW, the maximum Stokes laser power of 25.1 mW was measured and a tuning range of 50 nm without any self-lasing cavity modes was obtained.

Widely tunable multi-wavelength Brillouinerbium fiber laser utilizing low SBS threshold photonic crystal fiber.

A widely tunable low stimulated Brillouin scattering (SBS) photonic crystal fiber (PCF) based multi-wavelength Brillouin-erbium fiber laser is presented. The fiber laser structure utilizes a pre-amplified Brillouin pump (BP) technique with 100 m of PCF and a tunable band-pass filter within a Fabry-Perot cavity. A total of 14 Brillouin Stokes lines can be tuned over 29 nm from 1540 nm to 1569 nm. The wide tunability was only limited by the bandwidth of the tunable band-pass filter. A constant channel spacing of 0.079 nm and signal to noise ratio (SNR) of more than 20 dB for each Brillouin Stokes lines were also observed.

Reduction of gain depletion and saturation on a Brillouin-erbium fiber laser utilizing a Brillouin pump preamplification technique.

This paper presents the characteristics of a multiwavelength L-band Brillouin-erbium comb fiber laser with a preamplified Brillouin pump (BP) power technique at low pumping powers. The issue of erbium-doped fiber gain depletion and Brillouin gain saturation are resolved by the proposed structure. For long single-mode fiber length, the Stokes line emission occurs at low pumping powers because of the high strength of spontaneous Brillouin scattering, which provides a strong seed for coherent regenerative amplification of the Stokes line in the laser cavity. The laser structure achieves a low threshold power of 17 mW and is able to produce high number of output channels at low pumping powers. We experimentally show that the fiber laser structure can produce up to 37 channels at 55 and 0.045 mW of 1480 nm pump and BP powers, respectively.

Optimization of output coupling ratio on the performance of a ring-cavity Brillouin-erbium fiber laser.

The operation of a single-wavelength Brillouin-erbium fiber laser (BEFL) system with a Brillouin pump preamplified technique for different output coupling ratios in a ring cavity is experimentally demonstrated. The characteristics of Brillouin Stokes power and tunability were investigated in this research. The efficiency of the BEFL operation was obtained at an optimum output coupling ratio of 95%. By fixing the Brillouin pump wavelength at 1550 nm while its power was set at 1.6 mW and the 1480 pump power was set to its maximum value of 135 mW, the Brillioun Stokes power was found to be 28.7 mW. The Stokes signal can be tuned within a range of 60 nm from 1520 to 1580 nm without appearances of the self-lasing cavity modes in the laser system.

Tunable range enhancement of Brillouin-erbium fiber laser utilizing Brillouin pump pre-amplification technique.

We demonstrate an enhanced multiwavelength L-band Brillouin-erbium fiber laser (BEFL), in which the Brillouin pump is pre-amplified before entering the single-mode fiber. The Brillouin pump pre-amplification provided by the Erbium-doped fiber has created higher intensity of Brillouin Stokes line generated in the single-mode fiber that leads to the homogenous gain saturation. Thus the built-up of self-lasing cavity modes is suppressed in a wider wavelength range. In contrary to the conventional linear-cavity BEFL, the number of output channels is enhanced within the same tuning range.

Enhancement of multiwavelength generation in the L-band by using a novel Brillouin-Erbium fiber laser with a passive EDF booster section.

We demonstrate a novel scheme to generate multiple wavelengths in the L-band using a Brillouin-Erbium fiber laser. Our scheme utilizes extraneous amplified spontaneous emission in the C-band as a secondary pump source for a passive Erbium-doped fiber gain section along the cavity. The Brillouin gain medium is generated by the 6.7 km long of single mode fiber (SMF-28). We experimentally demonstrate that a total of 28 stable output channels with a spacing of 0.089 nm can be generated using our new scheme. This represents a 33% increase in the number of wavelengths generated compared with conventional schemes.

Characterization of a multiwavelength Brillouin-erbium fiber laser based on a linear cavity configuration.

We experimentally demonstrate a simple method for generating a multiwavelength Brillouin comb by utilizing a linear cavity of hybrid Brillouin-erbium fiber lasers (BEFLs). The optimization of Brillouin pump wavelength, power, and erbium gain played a significant role in determining the maximum number of Brillouin Stokes signals generated. Simultaneous and stable multiple-wavelength laser output of 22 lines with 10.88-GHz channel spacing has been obtained with good flatness. Various parameters such as 980-nm pump power, Brillouin pump wavelength, and Brillouin pump power that affect the performance of a multiwavelength BEFL system have been investigated. An analysis of the tuning range of the system is presented.