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The dynamics of semiconductor lasers subject to dual optical injections are numerically investigated with a zero linewidth enhancement factor. With the aid of stability maps, we show that different chaotic and nonlinear dynamics can be produced (even with zero linewidth enhancement factor) by injecting an additional optical signal. We also study the bifurcation of the system and the carrier dynamics under dual optical injection and a zero linewidth enhancement factor.

The study theoretically investigates the dynamic of an injection-locked semiconductor laser with zero linewidth enhancement factor. The stability map of the injection locking process is drawn, and bifurcation diagrams are generated. Carrier density dynamics are also investigated. The study has reported different periodical and chaotic behaviour and revealed the dynamics of carriers with zero linewidth enhancement factor.

This study examines the uncertainty associated with two commonly used GIS-based groundwater vulnerability models, DRASTIC and EPIK, in assessing seawater intrusion, a growing threat along coastal urban areas due to overexploitation of groundwater resources. For this purpose, concentrations of Total Dissolved Solids (TDS) in groundwater samples at three pilot areas along the Eastern Mediterranean were compared with mapped vulnerability predictions obtained through DRASTIC and EPIK. While field measurements demonstrated high levels of groundwater salinity depending on the density of urbanization, both vulnerability assessment methods exhibited a limited ability in capturing saltwater intrusion dynamics. In the three pilot areas, DRASTIC was only able to predict correctly between 8.3 and 55.6% of the salinity-based water quality ranges, while EPIK's predictions ranged between 11.7 and 77.8%. This emphasizing that conventional vulnerability models perform poorly when anthropogenic impacts induce lateral flow processes such as seawater intrusion caused primarily by vertical groundwater extraction.

This article examines the relative impacts of anthropogenic interventions and global climate change on the dynamics of saltwater intrusion in highly urbanized coastal aquifers. For this purpose, simulations of the impacts of sea-level rise and abstraction scenarios for the near future were undertaken for a pilot aquifer using a multi-objective 3D variable-density flow and solute transport model. We find that sea-level rise associated with climate change has less influence on the encroachment of salinity than anthropogenic abstraction, which has a more appreciable impact on saltwater intrusion through greater sensitivity to water consumption and seasonality.

Rivers are increasingly being subjected to increased anthropogenic pollution stresses that are undermining their designated-uses and negatively affecting sensitive coastal areas. In this study, the water quality of the Beirut River, a poorly monitored seasonal Mediterranean River, is quantified. Water quality samples were collected on a regular basis over two consecutive years (2016 and 2017) from four sampling sites that represent a gradient of increased urbanization. The spatio-temporal variability of the physio-chemical (pH, Total Suspended Sediment (TSS), Nitrates-nitrites (NOx), sulfates (SO4-2), Total Phosphorus (TP), Total Nitrogen (TN), temperature, conductivity, chemical oxygen demand (COD) and bio-chemical oxygen demand (BOD)) and biological (fecal coliform and total coliform) pollution levels were statistically analysed in an effort to better understand the contribution of point and non-point pollution sources. The results showed significant yearly as well as seasonal variability and a high correlation between the measured pollution levels and river flow levels. Spatially, pollution levels appeared to correlate well with the urbanization levels in the basin. Future work will focus on modeling and further characterizing the pollutant loads reaching the Beirut River Basin. It is hoped that this study will give decision makers a better understanding of the water quality in the Beirut River and thus facilitate the development of an integrated comprehensive and transparent river basin management plan.

The potential impacts of projected future climate change scenarios on the hydrologic response of a water-stressed Mediterranean river basin (Upper Litani River Basin in Lebanon) are quantified and assessed using the Water Evaluation and Planning (WEAP) model. Projected basin-level changes in water availability are then compared to multi-sector demands estimated under six basin-level development scenarios. The sustainability under these scenarios and the resilience of the system in the face of the projected climatic changes are then assessed in terms of a water resources index, demand reliability, demand satisfaction index, demand reliability index and the average duration of failure. The results reveal that the basin is expected to experience significant alteration in its hydrologic cycle and that current plans envisioning an increase in irrigated areas within the basin, is non-sustainable and will lead to a highly water stressed system. A conservative basin-level plan that integrates both supply- and demand-side measures is proposed in an effort to achieve a more sustainable system.

The optical properties of Gafchromic EBT films are investigated under various solar power intensities. The films are exposed to solar radiation with different powers (0, 0.3, 0.5, 0.8, 1 SUN) for 30 min in each case. The absorbance, transmittance and reflectance of the films are thoroughly investigated. Other important parameters such as: absorption coefficient, extinction coefficient, energy bandgaps and refractive index are determined. These parameters show strong dependence on the solar power intensity, suggesting that EBT films can be considered as suitable candidates for many sensing and dosimetry applications.

We have numerically investigated the dynamics of frequency shifts in semiconductor lasers under the injection of a frequency comb. We have studied the effect of comb spacing on the locking bandwidth. Frequency comb spacing was found to play an important role in the boundaries of the locking bandwidth as well as in the frequency shift of the SL peak.

The effect of the linewidth enhancement factor (LEF) on the frequency pulling behavior in optically injected lasers is theoretically investigated. The frequency pulling is found to be exponentially dependent on the LEF. This dependence is systematically revealed and explained.

OBJECTIVE: Both humoral and cellular immunity can be significantly influenced by the immunological responses to vaccination, and both responses are essential. Vaccination is the most consistent, safe, and cost-efficient practice for controlling the COVID-19 pandemic. PATIENTS AND METHODS: Blood samples were collected from participants who received two vaccine doses of COVID-19 Pfizer/BioNTech (BNT162b2) before and on days 7 and 10 after the first and second immunization. We evaluated some hematological and immunological markers responses to the 1st and 2nd doses of the BNT162b2 mRNA (Pfizer/BioNtech) vaccine. RESULTS: In healthy subjects' neutrophil and WBC counts significantly increased compared to those after the first dose. The results of all first-group participant categories demonstrated no discernible variations in lymphocyte counts. There was no change in IgM or IgG in all second- group cohorts, except for a considerable rise in IgG levels in people with a history of coronavirus infection following the second dosage compared to baseline. After the second dose, CD4+ T-cell and CD8+ T-cell levels rose in all groups compared to before the immunization and after the first dosage. Data demonstrated a sub-stantial rise in neutrophil-lymphocyte ratio (NLR) after the second dose of the vaccine. Individuals who had previously had COVID-19 disease experienced a considerable increase in C3 and C4 levels after the first and second dosages compared to baseline. Additionally, compared to their levels after the first dosage, C4 levels increased significantly following the second dosage. Interleukin (IL)-6, IL-15, macrophage colony-stimulating factor (M-CSF), granulocyte colony stimulating factor (G-CSF), interferon gamma-induced protein 10 (IP-10/CXCL10), and macrophage inflammatory protein-1 alpha (MIP-1α/CCL3) levels were increased after boost correlated with Spike antibody levels, supporting their utility as indicators of successful humoral immunity development in response to vaccination. CONCLUSIONS: We can conclude that the Pfizer/BioNTech vaccine produced a more potent T-cell response than humoral ones. [ABSTRACT FROM AUTHOR]

The goal of this research is to better understand the physical features of starburst galaxies. Radio and X-ray observations are good for exploring the stuff within the central regions of galaxies. A galaxy that is undergoing a strong star formation, usually in its central area, is known as a starburst galaxy. This paper provides the results of a statistical analysis of a sample of starburst galaxies. The data used in this research have been collected from NASA Extragalactic Database (NED), and HYPERLEDA. Those data have been used to examine possible luminosity correlations of X-ray to a radio of a sample of starburst galaxies. In this research, statistical software, known as statistic-win-program, has been used to investigate if there is a luminosity correlation between multiple-wavelength bands. The results of the statistical analysis conclude that there is a good correlation between X-ray luminosity and radio luminosity at 1.4GHz where the partial correlation coefficient is (R≈0.53) and slope (0.6±0.12). There is also a good correlation between X-ray luminosity and radio luminosity at 5GHz with a good partial correlation coefficient (R ≈ 0.65) and slope (0.77±0.11). There are good positive relationships between radio luminosity at (1.4GHz, 5GHz) with infrared and far-infrared luminosities (Log L1.4GHz α log LFIR 0.89±0.04 α Log LIR 0.9±0.03) with a very strong correlation equal to R=0.9 (Log L5GHz α Log LFIR 0.79±0.05 α Log LIR 0.81±0.05) with strong correlation R=0.8 both with very high probability level p≈10-7 . One of the closest and most ubiquitous correlations known among the global features of local star formation and starburst galaxies is the link between far-infrared (FIR) and radio emission. [ABSTRACT FROM AUTHOR]

The experimental and theoretical study of the dynamics of electron density in a semiconductor laser subjected to a wide range of optical injection strength is presented. The results reveal the overall dynamics of injection locked electron density variation, which was found to play a major role in pulling the SL resonance frequency outside the locking bandwidth, which was observed even at low injection and large detuning.