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Diversity, Ecology, and Environmental Significance of Foraminifera in Al Hamama and Susah Coastal Regions, Northeastern Libya: Insights from Holocene Sediments

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Journal of Environmental Protection 2024年第1期15卷 13-25页

作者： Belkasim Khameiss Husamaldeen Zubi Kansas Geological Survey Lawrence USA Department of Earth Sciences Faculty of Science University of Benghazi Benghazi Libya Department of Geology and Geological Engineering University of Mississippi Oxford USA Department of Geology Omar Al-Mukhtar University Al Bayda Libya

This research initiative, conducted along the coastal zones of Al Hamama and Susah in northeastern Libya, aimed to enhance our understanding of Holocene benthic foraminifera assemblages and the paleoenvironmental parameters in the region. We meticulously gathered five sediment samples to analyze the composition of foraminifera populations within the unconsolidated sedimentary deposits adjacent to these locations. We successfully identified nine distinct benthic foraminifera species, including Amphistegina lobifera, Eliphidium crispum, Sigmoilinita tenuis, Sorites orbiculus, Stomatorbina concentrica, Peneroplis planatus, Pseudotriloculina rotunda, Pyrgoella sphaera, and Triloculina schreberiana. Notably, Eliphidium crispum and Amphistegina lobifera emerged as the most prevalent species. These foraminifera species exhibited distinct ecological preferences, shedding light on paleoenvironmental conditions and climatic fluctuations during the Quaternary Period in the Susah and Al Hamama coastal regions. The presence of Orbulina universa, a planktonic foraminifera species, further enriched our understanding of the paleoenvironment by providing insights into specific water depths and temperature ranges. This research significantly contributes to paleoceanography and environmental reconstruction, highlighting the invaluable use of foraminifera as proxies for exploring past environmental changes. Additionally, the study investigated the impacts of anthropogenic influences on benthic ecosystems in the Al Hamama and Susah coastal areas. These influences included reworked foraminifera specimens and the effects of karst formations, acid rain, and eutrophication. Notably, human-induced factors have visibly affected biogenic fauna and ecosystem dynamics in the study area. Consequently, this research provides valuable insights into paleoenvironmental conditions and ecological dynamics within the Susah and Al Hamama coastal regions, emphasizing the crucial role of foraminifera in re

关键词： Al Hamama Susah Northeastern Libya Holocene Sediments

Competition between Coral and Algae in Tertiary and Quaternary Reefs: Greenhouse to Icehouse Transitions

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Journal of Environmental Protection 2024年第1期15卷 94-107页

作者： Belkasim Khameiss Richard Fluegeman William Hoyt Shawn Malone Ahmed Muftah Kansas Geological Survey Lawrence USA Department of Earth Sciences University of Benghazi Faculty of Science Benghazi Libya Department of Environment Geology and Natural Resources Ball State University Muncie USA Department of Earth and Atmospheric Sciences University of Northern Colorado Greeley USA Department of Geosciences University of Wisconsin—Green Bay Green Bay USA

The competition between coral and algae in marine reefs is pervasive through geologic time;that competition determines the structure and composition of reef communities, which we see in the fossil record. However, the relationships between coral and calcareous algae in reefs are poorly understood. To study this relationship, several hand samples and thin sections were examined from nine different foralgal reef localities around the world. Foralgal reefs typically extend from about 20 m depth or shallower on the seaward side of the reef. The first section is Salt Mountain, Alabama, which preserves a Paleocene reef. It contains a high percentage of red coralline algae with benthic foraminifera. The second section is IDOP-U1376, IIA Limestone, it is Middle Eocene, in the form of an isolated reef sandwiched between two igneous beds. The third section is the Utoe’ Limestone, New Caledonia, it is Middle Eocene in age and is composed mainly of grain-boundstone units with some igneous interlayered. The fourth section is the Darnah Formation in the West-Darnah roadcut section, Northeast Libya, it is Middle Eocene in age, it is composed of highly fossiliferous limestone (corals, red coralline algae, echinoids, mollusks, foraminifers, and bryozoans). The fifth section, the Al Bayda Formation (Algal Limestone Member) in Northeast Libya, is in the Drayanah—Al Abyar roadcut, Northeast Libya, it has several species of algae but also includes a high percentage of buildups of coral species. The sixth section is the Oligo-Miocene Al Faidiyah Formation (Al Fatayah Cement Quarry) limestone unit in Northeast Libya. The seventh section is (Core-core 20) late-early to middle Miocene Limestone Unit-Cicuco Field, NW Colombia. The eighth section is the benghazi Formation at benghazi Cement Quarry, in Northeast Libya, it is fossiliferous limestone, consisting of coral, algae, mollusks, and echinoids. The ninth and tenth sections are Quaternary reefs in the Bahamas and the Florida Keys, respec

关键词： Utoe’ Limestone New Caledonia benghazi Formation at benghazi Cement Quarry Is IDOP-U1376 IIA Limestone It Is Middle Eocene

Assessments of Antibacterial and Antioxidant Properties in the Methanolic and Aqueous Leaf Extracts of Pistacia lentiscus against Different Antibiotic Resistance Pathogenic Bacteria

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Advances in Bioscience and Biotechnology 2022年第3期13卷 113-133页

作者： Aml O. Alhadad Galal S. Salem Maraia F. Elmhdwi Suliman M. Hussein Sarah M. Elshareef Department of Botany Faculty of Science University of Benghazi Benghazi Libya Department of Chemistry (Biochemistry) Faculty of Science University of Benghazi Benghazi Libya

The current study was carried out to determine the bioactivity of P. lentiscus leaf extracts as potential antibacterial and antioxidant properties. The plant extracts were examined for antibacterial activity against antibiotic-resistant Staphylococcus aureus, Staphylococcus haemolyticus, Pseudomonas aeruginosa, and Proteus mirabilis using the agar well method (according to the guidelines of Clinical and Laboratory Standard Institute). The antioxidant potential of 3 plant leaf extracts was determined by their ability to convert Fe3+ to Fe2+ and scavenge the DPPH free radical. At all concentrations studied, the methanolic leaf extract had higher total phenolic and flavonoid content, as well as stronger antioxidant and antibacterial inhibitory activity compared to aqueous extract. Our findings with P. aeruginosa were especially interesting, because this bacterium was inhibited by methanol extract than that of the reference antibiotics. The results also demonstrated a link between DPPH radical scavenging ability, reducing power, and total phenolic and flavonoid content of plant extracts (r > 0.97, R2 > 0.95, P = 0.01). As a result, the methanolic leaf extract of the chosen plant might be employed as an effective antioxidant and antibacterial agent for the treatment of a variety of morbidities.

关键词： Antioxidant Activity Polyphenols Methanolic Leaf Extracts DPPH Reducing Power Pistacia lentiscus

The Prevalence of Human Cytomegalovirus Viremia among HIV-1 Infected Individuals Undergoing Antiretroviral Therapy

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Journal of Biosciences and Medicines 2023年第10期11卷 46-54页

作者： Farag A. Bleiblo Souad A. M. Moftah Madiha W. M. El-Awamie Samira F. M. Bo Hagar Asma A. Elamari Aida M. M. Elakeili Aseem Kumar Department of Microbiology Faculty of Science University of Benghazi Benghazi Libya Department of Chemistry and Biochemistry and the Biomolecular Sciences Programme Laurentian University Sudbury Canada Department of Physiology Faculty of Medicine-Al-Marj Campus University of Benghazi Benghazi Libya Department of Botany Faculty of Science University of Benghazi Benghazi Libya Department of Biology College of Education University of Benghazi Benghazi Libya

HIV infection is an emerging health issue in Libya, particularly among young adults. Human cytomegalovirus (HCMV) is a prevalent infectious agent that presents with subclinical and fatal diseases in immunosuppressed individuals including HIV-infected individuals. Although the impact of HCMV infection in HIV-positive patients is well documented in several regions, epidemiologic estimates concerning HCMV co-infection among HIV-infected individuals remain limited in Libya. Hence, this cross-sectional study was undertaken to derive data regarding the prevalence of active HCMV viremia among HIV-infected individuals undergoing antiretroviral therapy (ART) from Libya. A total of 90 consented HIV-infected subjects followed by the National Center for Disease Control (NCDC) of benghazi/Libya were recruited in this study and investigated for HCMV-IgG, HCMV-IgM specific antibodies, detection of HCMV lower matrix phosphoprotein (pp65) antigen, and detection of HCMV-DNA using qPCR to assess the prevalence of HCMV viremia. We determined that 77 (85.56%) of subjects were seropositive for HCMV-IgG antibodies, whereas the seropositivity for HCMV-IgM was 3.33% (3/90 subjects). Our results also revealed that 4.44% (4/90) of participants had viral antigenemia based on the laboratory diagnosis of HCMV-pp65. Regarding the PCR, we were able to detect the DNA of HCMV only in 3/90 subjects (3.33%) suggesting an active viremic condition. The detection of HCMV DNA along with the HCMV-pp65 in HIV-positive individuals highlights the necessity of early diagnosis to manage the progression of the disease. Furthermore, we highly recommend the use of anti-HCMV therapy in viremic individuals in combination with ART to reduce the burden of HCMV complications.

关键词： HCMV HIV IgG IgM qPCR Viremia Prevalence

PCTRAN Westinghouse AP1000 Power Control of Pressurized Water Reactor Using Simulink of MATLAB

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Open Journal of Energy Efficiency 2023年第2期12卷 25-35页

作者： Ezeddin A. M. Ben Ihrayz Department of Electrical and Electronic Engineering Faculty of Engineering University of Benghazi Benghazi Libya Hatif Libya Company Benghazi Libya

This paper introduces the simulation, and controls using Simulink of MATLAB for PCTRAN (Personal Computer Transient Analysis) of the power control system (PWR) type pressurized water reactor of PWR WESTINGHOUSE AP1000. The power controller model produces mathematical model description in nonlinear relation form in Simulink of MATLAB which is an important and popular program used at most universities for education. The power controller is described by a block diagram in this paper and some details introduce to clearly understand the work function. The results of action control compared with the PCTRAN programme in modes of automatic and manual control.

关键词： Turbine Leading Mode Reactor Leading Mode Rod Speed Program Rod Control Position Turbine Load Power

Synthesis and Characterisation of Cr(III) and Co(II) Schiff Base Complexes

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Materials Sciences and Applications 2023年第2期14卷 53-62页

作者： Fatin M. Elmagbari Ahmed N. Hammouda Hamdi A. M. Bennour Rashd M. EL-Ferjani Younis O. Ben Amer Department of Chemistry Faculty of Science University of Benghazi Qar-Yunis Benghazi Libya

Co(II) and Cr(III) metal complexes of Schiff bases were synthesized from the condensation reaction between 4-(dimethylamino)benzaldehyde and 4-amino-3-hydroxy-naphthalene-1-sulfonic acid. Their structures were investigated by elemental analysis, molar conductance measurements, infrared spectroscopy, electronic spectroscopy, and 1HNMR spectroscopy. The elemental analysis data suggested a 1:1 [M:L] ratio for the complexes. The molar conductance measurements of the complexes indicate their electrolytic nature in DMSO as a solvent. The absorption bands in the electronic spectra verified an octahedral environment around the metal ions in the complexes.

关键词： Schiff Base Ligand Complexes 1HNMR Spectra

Side Effects of Pfizer-BioNTech COVID-19 Vaccine among Libyan Young Adults: Observational Study

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Journal of Biosciences and Medicines 2022年第1期10卷 33-45页

作者： Taher I. Shailabi Elham O. Borwis Nisreen Saed Majeed Nagat H. Bubtina Naeima Betamar Guma Abdeldaim Pharmacology and Toxicology Department Faculty of Pharmacy Omar Al-Mukhtar University Al-Bayda Libya Medical Microbiology Department Faculty of Medicine Benghazi University Benghazi Libya Conservative Dentistry Department Faculty of Dentistry Benghazi University Benghazi Libya

Purpose: Since the mRNA technology used to manufacture Pfizer-BioNTech COVID-19 Vaccine is new, it is still difficult to predict its consequences. However, many young people, especially in developing countries, think that they are less susceptible to severe infection with the Coronavirus 2 (SARS-CoV-2), Therefore, they do not prefer to take the COVID-19 vaccines. Accordingly, studies in this aspect are necessary to increase people’s awareness of the acceptance of vaccination, especially for the youth. Patients and Methods: This study was conducted on healthy young adults of both sexes. Participants (n = 81) were received two doses of the Pfizer-BioNTech COVID-19 Vaccine. A paper questionnaire was prepared, the survey asks about the side effects related to receiving the Vaccine. All participants completed the questionnaire twice, once after the first dose and again after the second dose. Data were collected and statistically analyzed. Results: The most common side effects were Muscle pain, Tiredness, Headache, and Fever. Less common side effects were Chills, Fainted, Breathlessness, and Coughing. Rare side effects include nausea and vomiting, Diarrhea, Anaphylactic Reaction, and Swollen Lymph Nodes. Side effects that are strongly associated with females are Headache, and Joint pain, for males, Anaphylactic reaction. The study revealed a significant difference between the number of females (96.5%) and males (85%) who suffered from the side effects of the Pfizer-BioNTech COVID-19 Vaccine (P = 0.033). Conclusion: Most of the side effects reported in our study were consistent with Pfizer’s fact sheet for recipients and caregivers. Through our follow-up to the participants in the study, we noticed that the reported side effects were not too bad, and they were able to carry out their daily activities, so we recommend taking the vaccine, especially for young people.

关键词： Pfizer-BioNTech Side Effects COVID-19 Vaccine Young Adults

Isolation, Examination and Characterization of Actinomycetes as a Source of Antimicrobial Agents from Libyan Soil

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Advances in Bioscience and Biotechnology 2023年第6期14卷 322-336页

作者： Galal S. Salem Saleh H. Baiu Ali A. Ali Department of Botany Faculty of Science University of Benghazi Benghazi Libya Food Science Department and MIRCEN Cairo Faculty of Agriculture Ain-Shams University Cairo Egypt

The rapid increase of bacterial resistance strains to multiple antibiotics has become a global public health concern. In the present study, actinomycetes from different districts of Libyan soil were isolated and screened for their inhibitory activity against pathogenic bacteria and fungi. Three hundred soil samples were taken from 77 diverse ecosystems, including deserts, forests, pastureland, and cropland located in different climatic regions in Libya. A total of 164 actinomycetes were obtained. Of 164 isolates, 38 (23.2%) isolates were morphologically and microscopically characterized by spore chain and surface morphology, aerial and substrate mycelia and soluble pigments. The preliminary classification of the isolates illustrates that all isolates belong to the genus Streptomyces. These isolates were further examined for their antagonistic potential against nine pathogenic bacteria and fungi. Out of 38, 11 (28.9%) isolates showed their capability to produce inhibitory substances against at least two tested strains. Among bacterial strains, Staphylococcus aureus was susceptible to almost all eleven isolates (90.9%), while Streptococcus pyogenes was found to be resistant to most selected isolates (18.2%). The isolate, 063 (Wadan soil-desert zone) was the only isolate that exhibited broad spectrum antimicrobial activity against all tested pathogenic microbes, and hence was selected for further study. According to its cultural, morphological, physiological, and biochemical characteristics, the isolate 063 was identified as Streptomyces rochei. The results obtained indicate that the Libyan soil, particularly in extreme environments, could be a potent source of bioactive metabolites with antimicrobial potency against a wide variety of microbial pathogens. Thus, this investigation suggested that exploring new habitats in unexplored and untapped regions of Libya could provide a promising source of biologically active compounds for therapeutic applications.

关键词： Actinomycetes Antimicrobial Activity Isolation Streptomyces

Robust Stabilization of Load Frequency Control System Under Networked Environment

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International Journal of Automation and computing 2017年第1期14卷 93-105页

作者： Ashraf Khalil Ji-Hong Wang Omar Mohamed Electrical and Electronics Engineering Department University of Benghazi Benghazi Libya School of Engineering University of Warwick Coventry UK King Abdullah Ⅱ Faculty of Engineering Princess Sumaya University of Technology Amman Jordan

The deregulation of the electricity market made the open communication infrastructure an exigent need for future power system. In this scenario dedicated communication links are replaced by shared networks. These shared networks are characterized by random time delay and data loss. The random time delay and data loss may lead to system instability if they are not considered during the controller design stage. Load frequency control systems used to rely on dedicated communication links. To meet future power system challenges these dedicated networks are replaced by open communication links which makes the system stochastic. In this paper, the stochastic stabilization of load frequency control system under networked environment is investigated. The shared network is represented by three states which are governed by Markov chains. A controller synthesis method based on the stochastic stability criteria is presented in the paper. A one-area load frequency control system is chosen as case study. The effectiveness of the proposed method for the controller synthesis is tested through simulation. The derived proportion integration （PI） controller proves to be optimum where it is a compromise between compensating the random time delay effects and degrading the system dynamic performance. The range of the PI controller gains that guarantee the stochastic stability is determined. Also the range of the PI controller gains that achieve the robust stochastic stability is determined where the decay rate is used to measure the robustness of the system.

关键词： Load frequency control load frequency control (LFC) Markov chains networked control system robust stabilization.