Composition and age of Cenozoic volcanism in Libya

Libya has five major Cenozoic volcanic provinces (Garian, Jabal Al Haruj al Aswad, Jabal Al Hasawinah, Jabal as Sawda and Jabal Nuqay) that have a surface area of approximately 66,000 km2. These volcanic provinces are dominated by alkali to mildly alkali basalts. The provinces are aligned NNW-SSE, typically occurring where NE-SW trending structural features intersect the main regional uplift structures. Small volumes of phonolites are associated with the basaltic volcanism at Garian and Jabal Al Hasawinah. Despite their size and relative accessibility the Cenozoic volcanic provinces of Libya have been rarely studied. In the first part of this thesis I report a new study of the petrology, geochemistry (major and trace elements, REE, Sr-Nd isotopes) and geochronology (40Ar/39Ar) of basalts and phonolites from the Garian volcanic province in north Libya. These analyses indicate that the plateau and late basalts are not distinct basalt types produced from melting of different mantle regions at different times as proposed by earlier studies. They are the product of fractional crystallisation of a common parent. There is little indication of crustal contamination. Trace element and REE data support an origin in 2 to 12 % melts of heterogeneous sub-lithosphere mantle. Trace elements and Nd and Sr isotopic composition of the Garian basalts overlap values measured in metasomatised peridotite xenoliths in the GVP. They are compositionally similar to Cenozoic volcanism of northern Libya (e.g. Jabal Al Haruj) and southern Italy (e.g. Etna and Pantelleria; European asthenosphere mantle reservoir), and they lack the influence of enriched mantle present in other North African Cenozoic basalt provinces. Compositional variation in the Garian province phonolitic magmas is dominated by extensive fractional crystallisation (50-83%) of plagioclase and alkali feldspars combined with an unusual style of assimilation (2-45%) of old upper crust typical of Pan-African shield. The new high precision age determinations of the phonolites suggest that they were produced over a very short period at ~8.1 Ma. This contrasts strongly with previous age determinations that were 40-50 Ma. In the second half of the thesis I report new Ar/Ar chronology measurements for extrusive and intrusive rocks all the major Cenozoic volcanic fields in Libya. The major pulse of basaltic volcanism in Garian in the north (from 6 to 2 Ma) overlaps in time in Jabal Al Haruj province in southern Libya. Jabal Al Hasawinah and Jabal as Sawda basalts were erupted significantly earlier (23-10 Ma). Dykes and plugs at all provinces imply basaltic volcanism started in Miocene, followed by periods of erosion. There is no systematic trend of time in Cenozoic basaltic volcanism of Libya. It appears to be related to reactivation of ancient structures during the passive rifting that has been produced in response to interaction of African and European plates since the late Mesozoic

Bidirectional Synthesis, Photophysical and Electrochemical Characterization of Polycyclic Quinones Using Benzocyclobutenes and Benzodicyclobutenes as Precursors

Quinones have widespread applications in view of their interesting chemical and photophysical features. On the other hand, benzocyclobutenes (BCBs) are generally masked reactive dienes suitable for the [4+2] cycloaddition reactions. Here, benzocyclobutenes and benzodicyclobutenes (BDCBs) were prepared and further reacted with benzoquinone and naphthoquinone in order to obtain some new polycyclic quinones with highly extended π systems, namely, 6-bromo-5,8-dimethoxyanthracene-1,4-dione, 2,9-dibromo-1,4,8,11-tetramethoxypentacene-6,13-dione, 9-bromo-7,10-dimethoxytetracene-5,12-dione, 3,10-dimethoxycyclobuta[b]anthracene-1,5,8(2H)-trione, 6,10,17,21-tetramethoxynonacene-1,4,8,12,15,19-hexaone, and 3,12-dimethoxycyclobuta[b]tetracene-1,5,10(2H)-trione. In addition to their spectroscopic characterization the new compounds are investigated by UV and fluorescence spectroscopy, cyclic voltammetry, and DFT calculations

Evaluation Of Facial Soft Tissue Changes In Excessive Gingival Display Cases After Le Forte I Maxillary Impaction Surgery Using 3D Facial Surface Laser Scanner

Introduction: Facial soft tissue changes in relation to hard tissue movements after orthognathic surgery cases is always of concern to patients , surgical and orthodontics teams. The aim of the present study was to assess facial soft tissue changes and stability using 3D facial laser scanner after orthognathic surgery Le Forte I maxillary impaction in excessive gingival display patients. Methods: The subjects consisted of 12 patients with skeletal vertical maxillary excess (VME) causing an aesthetic concern to the patients in the form of “Gummy smile”, who underwent LeFort I osteotomy with maxillary impaction, Three-dimensional images of the patients were acquired with a 3D laser scanner preoperatively and postoperatively. The changes in facial soft tissue were detected using a colour coded map for analysis. Results: Significant change was recorded in the upper lip, alar base, nasolabial fold and nasal tip areas, without specification of this change in direction. Conclusions: The 3D images captured using the laser scanner in this study can be a useful tool for communication with both patients and professionals but cannot be relied upon solely for accurate analysis of the facial soft tissue changes. The colour coded map analysis cannot be relied upon solely as a method of analysis as it lacks an important aspect of the change which is the direction

Automated quantification of penile curvature using artificial intelligence

Objective: To develop and validate an artificial intelligence (AI)-based algorithm for capturing automated measurements of Penile curvature (PC) based on 2-dimensional images. Materials and methods: Nine 3D-printed penile models with differing curvature angles (ranging from 18 to 88°) were used to compile a 900-image dataset featuring multiple camera positions, inclination angles, and background/lighting conditions. The proposed framework of PC angle estimation consisted of three stages: automatic penile area localization, shaft segmentation, and curvature angle estimation. The penile model images were captured using a smartphone camera and used to train and test a Yolov5 model that automatically cropped the penile area from each image. Next, an Unet-based segmentation model was trained, validated, and tested to segment the penile shaft, before a custom Hough-Transform-based angle estimation technique was used to evaluate degree of PC. Results: The proposed framework displayed robust performance in cropping the penile area [mean average precision (mAP) 99.4%] and segmenting the shaft [Dice Similarity Coefficient (DSC) 98.4%]. Curvature angle estimation technique generally demonstrated excellent performance, with a mean absolute error (MAE) of just 8.5 when compared with ground truth curvature angles. Conclusions: Considering current intra- and inter-surgeon variability of PC assessments, the framework reported here could significantly improve precision of PC measurements by surgeons and hypospadiology researchers.Special thanks for Dr. Carlos Villanueva for providing us with the 3D printed penile models with pre-defined angulations utilized in -. Open Access Fund fees were supported by Qatar National Library.Scopu

The effect of invasive and non-invasive ventilation on neonatal hearing impairment

Background: The incidence of hearing loss in neonates is 2-4 cases in every 1000 live births. Hearing loss, especially in mild and moderate forms, may not be recognized before the second year, but may produce great defects in conversational abilities.Objective: The aim of the present study was to assess the hearing impairment with invasive and non-invasive ventilation in Zagazig University Hospitals.Patients and methods: This was a retrospective cohort study of preterm infants attending in neonatal intensive care unit (NICU) of Zagazig University hospital in the period of time between February 2021 and August 2021. The studied population included thirty preterm infants. Visual examination of the external auditory meatus and tympanic membrane was performed using a Welch Allyn Halogen Otoscope. Results: There was non-significant difference between the studied groups regarding gender, gestational age, or birth weight. There was significant increase in cesarean (CS) mode in nasal continuous positive airway pressure (NCPAP) group (86.7%) compared to 40% in synchronized intermittent mandatory ventilation (SIMV) group. On the other hand, there was non-significant difference between them regarding presence of maternal risk factors. About 50% of patients underwent NCPAP, while the other 50% underwent SIMV. The duration ranged from 7 to 13 days with mean 9.03 days. The Apgar at 1, 5 and 10 minutes and Down score; all were significantly lower in SIMV group. In each group, there was significant increase in Apgar score over time.Conclusion: There was no significant effect of invasive ventilation (SIMV) and non-invasive ventilation (NCPAP) on auditory function of preterm infants

Automated measurement of penile curvature using deep learning-based novel quantification method

ObjectiveDevelop a reliable, automated deep learning-based method for accurate measurement of penile curvature (PC) using 2-dimensional images.Materials and methodsA set of nine 3D-printed models was used to generate a batch of 913 images of penile curvature (PC) with varying configurations (curvature range 18° to 86°). The penile region was initially localized and cropped using a YOLOv5 model, after which the shaft area was extracted using a UNet-based segmentation model. The penile shaft was then divided into three distinct predefined regions: the distal zone, curvature zone, and proximal zone. To measure PC, we identified four distinct locations on the shaft that reflected the mid-axes of proximal and distal segments, then trained an HRNet model to predict these landmarks and calculate curvature angle in both the 3D-printed models and masked segmented images derived from these. Finally, the optimized HRNet model was applied to quantify PC in medical images of real human patients and the accuracy of this novel method was determined.ResultsWe obtained a mean absolute error (MAE) of angle measurement <5° for both penile model images and their derivative masks. For real patient images, AI prediction varied between 1.7° (for cases of ∼30° PC) and approximately 6° (for cases of 70° PC) compared with assessment by a clinical expert.DiscussionThis study demonstrates a novel approach to the automated, accurate measurement of PC that could significantly improve patient assessment by surgeons and hypospadiology researchers. This method may overcome current limitations encountered when applying conventional methods of measuring arc-type PC

Unlocking the potential of approved drugs for the allosteric inhibition of tropomyosin-receptor kinase A using molecular docking and molecular dynamics studies

Tropomyosin-receptor kinase A (TrkA) is the primary isoform among the tropomyosin-receptor kinases that have been associated with human cancer development, contributing to approximately 7.4% of all cancer cases. TrkA represents an attractive target for cancer treatment; however, currently available TrkA inhibitors face limitations in terms of resistance development and potential toxicity. Hence, the objective of this study was to identify new allosteric-approved inhibitors of TrkA that can overcome these challenges and be employed in cancer therapy. To achieve this goal, a screening of 9,923 drugs from the ChEMBL database was conducted to assess their repurposing potential using molecular docking. The top 49 drug candidates, exhibiting the highest docking scores (−11.569 to −7.962 kcal/mol), underwent MM-GBSA calculations to evaluate their binding energies. Delanzomib and tibalosin, the top two drugs with docking scores of −10.643 and −10.184 kcal/mol, respectively, along with MM-GBSA dG bind values of −67.96 and −50.54 kcal/mol, were subjected to 200 ns molecular dynamic simulations, confirming their stable interactions with TrkA. Based on these findings, we recommend further experimental evaluation of delanzomib and tibalosin to determine their potential as allosteric inhibitors of TrkA. These drugs have the potential to provide more effective and less toxic therapeutic alternatives. The approach employed in this study, which involves repurposing drugs through molecular docking and molecular dynamics, serves as a valuable tool for identifying novel drug candidates with distinct therapeutic uses. This methodology can contribute to reducing the attrition rate and expediting the process of drug discovery