Upper Paleocene-Lower Eocene biostratigraphy of Darb Gaga, Southeastern Kharga Oasis Western Desert, Egypt

© The Author(s), 2016. This is the author's version of the work and is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Journal of African Earth Sciences 118 (2016): 12-23, doi:10.1016/j.jafrearsci.2016.02.016.Paleontological studies on the Upper Paleocene-Lower Eocene succession at Darb Gaga, southeastern Kharga Oasis, Western Desert, Egypt document the changes associated with the Paleocene-Eocene Thermal Maximum (PETM), such as 1) a radical alteration of the relative and absolute abundance of planktonic foraminifera; 2) a massive occurrence of the excursion planktonic foraminiferal taxa; 3) a widespread deposition of calcarenite yielding atypical (extremely high) faunal abundance associated with the younger phase of warming; and 4) a concentration of coprolites associated with the middle phase of warming. We also document the Lowest Occurrence (LO) of dimorphic larger benthic and excursion foraminifera during the earlier phase of warming at Darb Gaga, as recorded in Bed 1 of the Dababiya Quarry Member. The absence of these faunas in Bed 1 at Dababiya (the GSSP for the P/E Boundary) is likely to be due to both intense deficiency in dissolved oxygen and massive carbonate dissolution. Only remains (fish remains) of faunas that can tolerate the toxicity produced by low oxygen conditions are found in the stratigraphic record of this (oldest) phase at Dababiya. The Dababiya Quarry Member (DQM) at Darb Gaga reflects the unfolding of the sedimentary and biotic changes associated with the PETM global warming at, and following, the Paleocene/Eocene boundary on the southern Tethys platform. The changes began with a rapid increase in bottom and “intermediate” water temperature. The temperature increase was accompanied by removal of oxygen during the early and middle stages of warming. This led to the absence of both subbotinids and calcareous benthic foraminifera in the early and second coprolite-bearing phases (Beds 2 and 3 of the DQM). Dissolution seems to have no role during these stages as shown by the unusual abundance and good preservation of the warm-tolerant Ac. sibaiyaensis. This species reaches its maximum abundance in Bed 2 where it exhibits a broad range of size (63-250 μm) and shape that probably reflect optimal growth under the warmest water conditions. Thus, we infer that temperature and dissolved oxygen content of the sea-water were the main factors controlling the distribution pattern(s) of the microplankton and microbenthos during the PETM.2017-02-2

The Northern Lakes and Surrounding Plains in the Nile Delta, Egypt: How Are They Now and How Will They Are in Light of Climate Changes

In addition to the consensus of scientists, environmental experts, fisheries and beach research in Egypt about the pollution of the northern lakes in the Egyptian delta and the collapse of its ecosystem as a result of using these lakes as a permanent drain for agricultural, health and industrial wastewater - untreated - for the delta governorates surrounding the lakes - the continuous drying processes in the Manzala lakes Burullus, Mariout and Idku, which the government undertakes on the one hand, and individuals on the other hand, have caused a change in the morphology of the lakes and a reduction in their areas, ranging between 46% and 83% of their original areas. Drying and filling works are still going on for these lakes, without taking into account the new climatic conditions that have hit the world, which in turn will lead to a rise in the global sea level (MGSL) during this century by an amount that may reach a maximum of one meter. This will result in the invasion of all the northern lakes of the Nile Delta, in addition to the surrounding dry low plains along the northern coast of the delta, and then the invasion of all the areas that were previously deducted and drained from the lakes with their urban, agricultural and industrial projects, as well as the remaining submerged areas of these lakes, which in turn will lose their characteristics to become part of the Mediterranean. This study aims to determine the quantitative and qualitative size of the certain risks that will face the northern lakes and the plains surrounding them in the Nile delta as a result of the global rise in sea level during this century, the coastal threat sources and the traditional defensive policies that must be followed to avoid all these risks

Groundwater Sapping Process and Runoff of Old River Systems in the Great Sand Sea and the Gilf El Kebir Plateau, Western Desert of Egypt

The present work delineates two main patterns of drainage in the Western Province of the Western Desert. The first pattern was formed by runoff of old river systems and has a restricted geographic distribution on the top surface and slopes of the scarps of the Gilf El Kebir Plateau but it is generally low, intermittent, having a limited duration in the westernmost part of the Great Sand Sea along the Egyptian-Libyan borders. The second pattern was and still formed by groundwater sapping process which has a widespread distribution along the slopes of the Gilf El Kebir Plateau, the Nubia Sandstone hills distributed in the Dakhla Basin and the slopes of the widely distributed longitudinal Nubia Sandstone ridges in the Great Sand Sea between the Gilf El Kebir in the south and Siwa Oasis in the north. The phenomenon of lateral flowing of groundwater and its emergence as seeps at the edges of the scarps was and still today the main erosion process that produces major landforms with unique characteristics in the Great Sand Sea. It causes disintegration and breakdown of the Nubia Sandstone bedrock and erosion of the sandstone from the slopes, causing the slopes to be undermined and undergo mass wasting. It is also the predominant mechanism of the growth of the amphitheater-headed valleys, and the flat-topped surfaces of the upraised plateaus as well as the exploitation of joints and fractures in the Nubia Sandstone bedrock. In addition it is responsible of formation of different types of alcoves in headwalls, spring sites and seepage zones in many valley flanks. Moreover, vast areas of the Nubia Sandstone bedrock of the flat-topped plateaus, flat tracks and depressions are found to be eroded, well exposed, clean, and covered by silica debris as a result of intense erosion by the groundwater seepage

Clinical Implications of COVID-19 Presence in CSF: Systematic Review of Case Reports

This systematic review focused on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) patients that had detected SARS-CoV-2 virus in cerebrospinal fluid (CSF). A systematic literature search was carried out in PubMed, Embase, Scopus, Web of Science, Medrxiv, and Biorxiv databases from inception to 19 December 2021. Case reports or case series involving patients with proved SARS-CoV-2 presence in CSF by polymerize chain reaction were included. Our search strategy produced 23 articles documenting a total of 23 patients with positive SARS-CoV-2 in the CSF. Fever (55%) was the most common symptom, followed by headaches (41%), cough (32%), and vomiting/nausea (32%). The majority of the cases included was encephalitis (57%), 8 of which were confirmed by magnetic resonance imaging. The second most prevalent presentation was meningitis. The cerebral spinal fluid analysis found disparities in protein levels and normal glucose levels in most cases. This study demonstrates that SARS-CoV-2 can enter the nervous system via various routes and cause CNS infection symptoms. SARS-CoV-2 has been shown to infect the CNS even when no respiratory symptoms are present and nasopharyngeal swabs are negative. As a result, SARS-CoV-2 should be considered as a possible cause of CNS infection and tested for in the CSF.Open Access funding provided by the QU Health, Qatar University

Emerging roles of activating transcription factor 2 in the development of breast cancer: a comprehensive review.

Activating transcription factor 2 (ATF2) is a member of the leucine zipper family of DNA binding proteins that are responsible for regulating various genes that play an essential role in major biological and cellular functions. Since ATF2 plays a vital role in cellular proliferation and apoptosis, it is believed that it greatly affects the development of breast cancers. However, its exact role in breast cancer is incompletely understood. It remains a subject of debate, ambiguity, and continuous research. Several studies have suggested the role of ATF2 as an oncogene, promoting cellular proliferation and worsening the outcome of cancers. In contrast, other studies have postulated that ATF2 plays a tumor suppressive role in estrogen receptor-positive breast cancer. The ambiguity surrounding its role in breast cancer is the reason why there is an influx of recent studies and research in this area. In this narrative review, we investigate several studies that have been published about the role of ATF2 in breast cancer. We also explore studies that have examined the association between ATF2 and endocrine therapy resistance. ATF2 has been suggested to modulate estrogen receptor (ER) expression and activity, potentially affecting tamoxifen sensitivity in breast cancer cells. Therefore, the role of ATF2 in DNA repair mechanisms and drug resistance has been deeply explored in this review. Additionally, there are numerous ongoing clinical trials exploring the effect of targeting ATF2 pathways and mechanisms on the outcome of breast cancers, some of which we have discussed. The studies and clinical trials that are being conducted to understand the multifaceted role of ATF2 and its signaling pathways may provide valuable insight for developing efficient targeted therapeutic solutions to enhance the outcomes of breast cancer and overcome endocrine resistance. We suggest further research to elucidate the dual roles of ATF2 in breast cancer and potential therapeutic therapies for its treatment

Pharaonic necrostratigraphy : a review of geological and archaeological studies in the Theban Necropolis, Luxor, West Bank, Egypt

Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of John Wiley & Sons for personal use, not for redistribution. The definitive version was published in Terra Nova 21 (2009): 237-256, doi:10.1111/j.1365-3121.2009.00872.x.We present a review of archeological and geological studies on the West Bank as a basis for discussing the geological setting of the tombs and geologically related problems with a view to providing archeologists with a framework in which to conduct their investigations on the restoration, preservation and management of the antique monuments. Whereas the geology of the Upper Nile Valley appears to be deceptively simple, the lithologic succession is vertically variable, and we have recognized and defined several new lithologic units within the upper Esna Shale Formation. We have been able to delineate lithologic (shale/limestone) contacts in several tombs and observed that the main chambers in some were excavated below the Esna Shale in the Tarawan Chalk Formation. We have been able to document changing dip in the strata (warping) in several tombs, and to delineate two major orientations of fractures in the field. Investigations behind the Temple of Hatshepsut, in the Valley of the Kings and around Deir El Medina, have revealed four broad regional structures. We confirm that the hills located near the Nile Valley, such as Sheik Abel Qurna, do not belong to the tabular structure of the Theban Mountain, but are discrete displaced blocks of the Thebes Limestone and overlying El Miniya, as supported by Google Earth photographs

The role of geoarchaeology in the preservation and management of the Theban Necropolis, West Bank, Egypt

A World Heritage Site since 1979, the Theban Necropolis was built by the Pharaohs of the 18th to 20th Dynasties (c. 1539 – 1075 BCE). A variety of pharaonic (and lesser nobles') tombs, funerary temples and sanctuaries were located/excavated in the lower part of the c. 400 m high pyramidal El Qurn in a variety of lithofacies (predominantly marine limestones and shales). These monuments are located in regionally persistent structural entities as well as gravitational collapse structures (GCS) whose probable origin and timing are reviewed and updated here, based on information that was unavailable to us at the time of writing a complementary paper in 2008 (but only published in 2015). We review here the historical development of the Theban Necropolis in the framework of the geological and geomorphological landscape and the first geological map of the region prepared by our Working Group for the Theban International Geoarcheological Project (TIGA) in 2011. We conclude with a preferential prioritizing of the perceived short- and long-term threats to the preservation of the Theban Necropolis and its monuments: least vulnerable to destabilization are the Valley of the Kings, Valley of the Queens, Block of Sheik Abdel Qurnah – El Khokkah; more vulnerable are Deir El Medina, Qunet Mura'I and El Assasif; most vulnerable are the Village of the Workers, Deir El Bahari and the Valley of the Colors. Accordingly it will be necessary to devise geotechnical solutions to prevent the destruction of (at least) some of the monuments under consideration here

The Dababiya corehole, Upper Nile Valley, Egypt : preliminary results

Author Posting. © Austrian Geological Society, 2012. This article is posted here by permission of Austrian Geological Society for personal use, not for redistribution. The definitive version was published in Austrian Journal of Earth Sciences 105, no. 1 (2012): 161-168.The Dababiya corehole was drilled in the Dababiya Quarry (Upper Nile Valley, Egypt), adjacent to the GSSP for the Paleocene/ Eocene boundary, to a total depth of 140 m and bottomed in the lower Maastrichtian Globotruncana aegyptiaca Zone of the Dakhla Shale Formation. Preliminary integrated studies on calcareous plankton (foraminifera, nannoplankton), benthic foraminifera, dinoflagellates, ammonites, geochemistry, clay mineralogy and geophysical logging indicate that: 1) The K/P boundary lies between 80.4 and 80.2 m, the Danian/Selandian boundary between ~ 41 and 43 m, the Selandian/Thanetian boundary at ~ 30 m (within the mid-part of the Tarawan Chalk) and the Paleocene/Eocene boundary at 11.75 m (base [planktonic foraminifera] Zone E1 and [calcareous nannoplankton] Zone NP9b); 2) the Dababiya Quarry Member (=Paleocene/Eocene Thermal Maximum interval) extends from 11.75 to 9.5 m, which is ~1 m less than in the adjacent GSSP outcrop.; 3) the Late Cretaceous (Maastrichtian) depositional environment was nearshore, tropical-sub tropical and nutrient rich; the latest Maastrichtian somewhat more restricted (coastal); and the early Danian cooler, low(er) salinity with increasing warmth and depth of water (i.e., more open water); 4) the Paleocene is further characterized by outer shelf (~ 200 m), warm water environments as supported by foraminifera P/B ratios > 85% (~79-28 m), whereas benthic foraminifera dominate (>70%) from ~27-12 m (Tarawan Chalk and Hanadi Member) due, perhaps, in part to increased dissolution (as observed in nearby outcrop samples over this interval); 5) during the PETM, enhanced hydrodynamic conditions are inferred to have occurred on the sea-floor with increased river discharge (in agreement with sedimentologic evidence), itself a likely cause for very high enhanced biological productivity on the epicontinental shelf of Egypt; 6) correlation of in situ measured geophysical logs of Natural Gamma Ray (GR), Single-Point Resistance (PR), Self-Potential (SP), magnetic susceptibility (MS), and Resistivity, and Short Normal (SN) and Long Normal (LN) showed correspondence to the lithologic units. The Dababiya Quarry Member, in particular, is characterized by very high Gamma Ray and Resistivity Short Normal values.The Dababiya corehole was made possible by the financial support of the National Geographic Society

Water requirements for wheat and maize under climate change in North Nile Delta

Determination of water requirements for wheat and maize under climate change is important for policy makers in Egypt. The objectives of this paper were to calculate (i) ETo and (ii) water requirements for wheat and maize crops grown in five governorates (Alexandria, Demiatte, Kafr El-Sheik, El-Dakahlia and El-Behira) located in North Nile Delta of Egypt under current climate and climate change. ECHAM5 climate model was used to develop A1B climate change scenario in 2020, 2030 and 2040. Monthly values of evapotranspiration (ETo) under the different scenarios in these governorates were calculated using Hargreaves-Samani equation (H-S). Then, these values were regressed on ETo values previously calculated by Penman-Monteith equation (P-M) and linear regression (prediction equations were developed for each governorate). The predicted ETo values were compared to the values of ETo calculated by P-M equation and the deviations between them were very low (RMSE/obs=0.04-0.06 mm and R2 =0.96-0.99). Water requirements for wheat and maize were calculated using BISm model under current climate and in 2020, 2030 and 2040. The results showed that average annual ETo would increase by low percentage in 2020 and 2030. However, in 2040 the increase would reach 8%. Water requirements are expected to increase by 2-3% for wheat and by 10-15% for maize, which would result in reduction of the cultivated area. Thus, it is very important to revise and fix the production system of wheat and maize, in terms of the used cultivars, fertilizer and irrigation application to overcome the risk of climate change

Water requirements for wheat and maize under climate change in North Nile Delta

Determination of water requirements for wheat and maize under climate change is important for policy makers in Egypt. The objectives of this paper were to calculate (i) ETo and (ii) water requirements for wheat and maize crops grown in five governorates (Alexandria, Demiatte, Kafr El-Sheik, El-Dakahlia and El-Behira) located in North Nile Delta of Egypt under current climate and climate change. ECHAM5 climate model was used to develop A1B climate change scenario in 2020, 2030 and 2040. Monthly values of evapotranspiration (ETo) under the different scenarios in these governorates were calculated using Hargreaves-Samani equation (H-S). Then, these values were regressed on ETo values previously calculated by Penman-Monteith equation (P-M) and linear regression (prediction equations were developed for each governorate). The predicted ETo values were compared to the values of ETo calculated by P-M equation and the deviations between them were very low (RMSE/obs=0.04-0.06 mm and R2 =0.96-0.99). Water requirements for wheat and maize were calculated using BISm model under current climate and in 2020, 2030 and 2040. The results showed that average annual ETo would increase by low percentage in 2020 and 2030. However, in 2040 the increase would reach 8%. Water requirements are expected to increase by 2-3% for wheat and by 10-15% for maize, which would result in reduction of the cultivated area. Thus, it is very important to revise and fix the production system of wheat and maize, in terms of the used cultivars, fertilizer and irrigation application to overcome the risk of climate change. Additional key words: Triticum spp; Zea mays; Penman-Monteith equation; Hargreaves-Samani equation; BISm model; ECHAM5 climate model; A1B climate change scenario. Abbreviations used: BISm (basic irrigation scheduling model); CCAFS (Climate Change, Agriculture and Food Security); ETo (evapotranspiration); H-S (Hargreaves & Samani); Kc (crop coefficient); PI (percentage of increase); P-M (Penman Monteith); RMSE (root mean square error); WHC (water holding capacity). Citation: Ouda, S.; Noreldin, T.; Abd El-Latif, K. (2015). Water requirements for wheat and maize under climate change in North Nile Delta. Spanish Journal of Agricultural Research, Volume 13, Issue 1, e03-001, 10 pages. http://dx.doi.org/10.5424/sjar/2015131-6412. Received: 15 Jun 2014. Accepted: 02 Dec 2014. http://dx.doi.org/10.5424/sjar/2015131-6412 Copyright © 2015 INIA. This is an open access article distributed under the Creative Commons Attribution License (CC by 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Funding: The author(s) received no specific funding for this work. Competing interests: The authors have declared that no competing interests exist. Correspondence should be addressed to Samiha Ouda: [email protected]