Study of Microbial Enhanced Oil Recovery using Indigenous Bacteria in Egyptian Oil Reservoirs

Microorganisms provide a unique opportunity for improving oil recovery economically and environmentally in a technique called “Microbial Enhanced Oil Recovery MEOR”. This study highlights the importance and potential of microbiology in petroleum engineering. Biosurfactant production is one of the most efficient mechanisms in microbial enhanced oil recovery (MEOR) processes. Biosurfactants have recently attained extended attention because they have numerous benefits over chemical synthetic surfactants, including higher biodegradability, lower toxicity, higher foaming, environmental compatibility, and effective properties under harsh conditions. The present study investigates the production of biosurfactants by indigenous bacteria isolated from Egyptian oil fields, and the use of these biosurfactants in enhancing the oil recovery. Fifty-nine Egyptian oil reservoirs were screened to investigate the potential for MEOR in Egyptian oil fields. The results showed that 8 reservoirs from the Gulf of Suez and 3 reservoirs from the Western Desert had the potential for MEOR. The bacterial isolation and identification of the collected crude oil samples from the Egyptian oil fields that have the potential for MEOR showed 11 isolated strains, which are Pseudomonas stutzeri, Clostridium spp, pseudomonas aeruginosa, pseudomonas fluorescens, Brevibacterium spp, Cellulosimicrobium spp, Pseudomonas panipatensis, Enterobacter spp, Bacillus flexus, Bacillus licheniformis, and Bacillus subtilis. The isolated strains Bacillus subtilis and Bacillus licheniformis were selected for further studies in this research because they are reported as good biosurfactants-producing bacteria under facultative or anaerobic conditions, spore forming, and non-pathogenic. The results of surface activity and bacteria growth examination also showed that the selected bacterial strains Bacillus licheniformis and Bacillus subtilis could produce effective biosurfactants that reached their maximum surface activity and reach maximum after 24 h of incubation. The results of emulsification activity examination showed that produced biosurfactants by Bacillus licheniformis and Bacillus subtilis could significantly emulsify crude oil with emulsification indices of 50% and 64%, respectively. The contact angle measurement showed that the oil was more detached from the sandstone surface when submerged in an aqueous solution of the produced biosurfactants, where the biosurfactants produced by Bacillus subtilis and Bacillus licheniformis decreased the contact angle of the oil drop from 104.96° and 107.30° to 85.40° and 88.72° after 24 h, respectively. Similarly, the new proposed medium decreased the contact angle of the oil drop from 112.30° and 110.90° to 63.85° and 69.33° after 24 h, respectively, which could facilitate the recovery of remaining oil. High stability was observed at high temperatures for a long-time period and more than 60% of their surface and emulsification activities were maintained over a wide range of pH and salinity. The core flooding tests showed the potential of the biosurfactants produced by Bacillus licheniformis and Bacillus subtilis to recover up to 31% and 39% of additional oil over the water flooding residual oil saturation under simulated reservoir conditions, respectively. In addition to the beneficial effects of the selected indigenous bacteria in producing effective biosurfactants, the performed environmental risk assessment showed that Bacillus licheniformis and Bacillus subtilis are environmentally safe, have no potential for toxicity, and no risk could occur for MEOR

Structural and optical characteristics of poly(vinyl alcohol)/carboxymethyl cellulose/ curcumin nanocomposites

ABSTRACT. Curcumin nanoparticles (CurNP’s) were successfully synthesized, characterized, and used as a cross-linking dopant of polyvinyl alcohol/ sodium carboxymethyl cellulose (PVA/CMC) semi-natural polymer blend. Synthesized nanocomposite films of (PVA/CMC/CurNP’s) were characterized using Fourier transforms infrared FTIR spectroscopy and tested for their resistance of different bacterial grams. Obtained data shows that studied PVA polymerized and cross-linked with CMC as a result for hydrogen bonding between the carboxylic groups and with the non-substituted hydroxyl groups of the cellulose molecule. The optical energy gap was found to be sensitive for the CurNP’s doping level, and the indirect transition was dominant in the studied samples. The addition of CurNP’s appears to increase the activity index of all samples against both gram-negative and positive bacteria, and their activity increases with increasing dopant level until a specific optimal concentration.                     KEY WORDS: Curcumin nanoparticles, Semi-natural polymer blend, Antibacterial, FTIR, Optical energy gap   Bull. Chem. Soc. Ethiop. 2021, 35(3), 615-624. DOI: https://dx.doi.org/10.4314/bcse.v35i3.1

SDG Final Decade of Action: Resilient Pathways to Build Back Better from High-Impact Low-Probability (HILP) Events

Data Availability Statement: Not applicable.Copyright © 2022 by the authors. The 2030 Sustainable Development Goals (SDGs) offer a blueprint for global peace and prosperity, while conserving natural ecosystems and resources for the planet. However, factors such as climate-induced weather extremes and other High-Impact Low-Probability (HILP) events on their own can devastate lives and livelihoods. When a pandemic affects us, as COVID-19 has, any concurrent hazards interacting with it highlight additional challenges to disaster and emergency management worldwide. Such amplified effects contribute to greater societal and environmental risks, with cross-cutting impacts and exposing inequities. Hence, understanding how a pandemic affects the management of concurrent hazards and HILP is vital in disaster risk reduction practice. This study reviews the contemporary literature and utilizes data from the Emergency Events Database (EM-DAT) to unpack how multiple extreme events have interacted with the coronavirus pandemic and affected the progress in achieving the SDGs. This study is especially urgent, given the multidimensional societal impacts of the COVID-19 pandemic amidst climate change. Results indicate that mainstreaming risk management into development planning can mitigate the adverse effects of disasters. Successes in addressing compound risks have helped us understand the value of new technologies, such as the use of drones and robots to limit human exposure. Enhancing data collection efforts to enable inclusive sentinel systems can improve surveillance and effective response to future risk challenges. Stay-at-home policies put in place during the pandemic for virus containment have highlighted the need to holistically consider the built environment and socio-economic exigencies when addressing the pandemic’s physical and mental health impacts, and could also aid in the context of increasing climate-induced extreme events. As we have seen, such policies, services, and technologies, along with good nutrition, can significantly help safeguard health and well-being in pandemic times, especially when simultaneously faced with ubiquitous climate-induced extreme events. In the final decade of SDG actions, these measures may help in efforts to “Leave No One Behind”, enhance human–environment relations, and propel society to embrace sustainable policies and lifestyles that facilitate building back better in a post-pandemic world. Concerted actions that directly target the compounding effects of different interacting hazards should be a critical priority of the Sendai Framework by 2030.This research received no external funding

Global overview of the management of acute cholecystitis during the COVID-19 pandemic (CHOLECOVID study)

Background: This study provides a global overview of the management of patients with acute cholecystitis during the initial phase of the COVID-19 pandemic. Methods: CHOLECOVID is an international, multicentre, observational comparative study of patients admitted to hospital with acute cholecystitis during the COVID-19 pandemic. Data on management were collected for a 2-month study interval coincident with the WHO declaration of the SARS-CoV-2 pandemic and compared with an equivalent pre-pandemic time interval. Mediation analysis examined the influence of SARS-COV-2 infection on 30-day mortality. Results: This study collected data on 9783 patients with acute cholecystitis admitted to 247 hospitals across the world. The pandemic was associated with reduced availability of surgical workforce and operating facilities globally, a significant shift to worse severity of disease, and increased use of conservative management. There was a reduction (both absolute and proportionate) in the number of patients undergoing cholecystectomy from 3095 patients (56.2 per cent) pre-pandemic to 1998 patients (46.2 per cent) during the pandemic but there was no difference in 30-day all-cause mortality after cholecystectomy comparing the pre-pandemic interval with the pandemic (13 patients (0.4 per cent) pre-pandemic to 13 patients (0.6 per cent) pandemic; P = 0.355). In mediation analysis, an admission with acute cholecystitis during the pandemic was associated with a non-significant increased risk of death (OR 1.29, 95 per cent c.i. 0.93 to 1.79, P = 0.121). Conclusion: CHOLECOVID provides a unique overview of the treatment of patients with cholecystitis across the globe during the first months of the SARS-CoV-2 pandemic. The study highlights the need for system resilience in retention of elective surgical activity. Cholecystectomy was associated with a low risk of mortality and deferral of treatment results in an increase in avoidable morbidity that represents the non-COVID cost of this pandemic

Biosurfactant production using Egyptian oil fields indigenous bacteria for microbial enhanced oil recovery

Biosurfactant production is one of the most efficient mechanisms in microbial enhanced oil recovery (MEOR) processes. This work investigates the production of biosurfactants by indigenous bacteria isolated from Egyptian oil fields, and how to optimize these produced biosurfactants for MEOR. 59 Egyptian oil reservoirs were screened to evaluate the potential applicability of MEOR processes, based on their rock and fluid properties. Results showed that 8 reservoirs from the Gulf of Suez and 3 reservoirs from the Western Desert had the potential to MEOR. Combined analysis of morphological, and biochemical characterization was performed on the 11 bacterial strains isolated from different crude oil samples collected from the reservoirs that have the potential to MEOR process to identify their types. Bacillus spp, a bacilli species that can produce biosurfactants, was selected for further studies. To optimize the surface activity of the produced biosurfactant, ten different reported nutrient media, and a new proposed nutrient media were examined. Bacillus spp has shown the ability to produce a very active biosurfactant that reduced the surface tension of water from 71.8 ± 1.9 mN/m to 25.7 ± 1.2 mN/m, and the interfacial tension of water against kerosene from 48.4 ± 2.1 mN/m to 0.38 ± 0.07 mN/m at Critical Micelle Concentration (CMC) of 0.04 ± 0.01 g/l, in a medium supplemented by the new proposed nutrient medium H. The growth rate of Bacillus spp was studied, and it was found it reached its maximum (OD600nm 2.59 ± 0.16) after 24 h of incubation. Biosurfactant production has no significant change in its surface activity over a wide range of temperature range up to 120 °C, which means the studied species Bacillus spp is a thermophilic bacterium. Bacillus spp grew well in the presence of high salt concentration up to 20% (w/v) NaCl, the optimal surface activity was obtained in the range of 0–2% (w/v) NaCl, and at pH 7. The emulsification activity of the produced biosurfactant was examined, and it reached the maximum (69.6 ± 1.5%) against kerosene at temperature 25 °C, Salinity 0% (w/v) NaCl (distilled water), and pH 7. The produced biosurfactant was purified and extracted by acid precipitation method, and the biosurfactant yield of the purified compound was found to be 2.8 ± 0.3 g/l. Finally, the core-flooding experiments were conducted to investigate the effect of produced biosurfactants by Bacillus subtilis in oil recovery. The obtained results reveal the potential of Bacillus spp to grow in the new proposed medium H and produce effective and efficient biosurfactants that enhanced oil recovery by 25.19–39.35% of additional oil over the water flooding residual oil saturation in the studied cores and retain more than 60% of its surface activity under harsh conditions and that are relevant to Microbial Enhanced Oil Recovery, MEOR

Incidence and risk factors of retinopathy of prematurity in neonatal intensive care units: Mansoura, Egypt

Background Retinopathy of prematurity ROP is a leading cause of blindness affecting ∼50 000 children worldwide. The incidence of the disease varies among different countries, it is influenced by the level of perinatal care, the existence of screening programs for early diagnosis. Low birth weight BW, small gestational age GA, other antenatal, postnatal risk factors have been identified with their relation to the severity of the disease. Aim The aim of this research was to study the incidence and risk factors of ROP in preterm babies at neonatal intensive care units, Mansoura city. Patients and methods This study included 402 preterm infants admitted to neonatal intensive care units in Mansoura city in the period from March 2013 to March 2015. Fundus examination was done using indirect ophthalmoscopy and a 28 D lens, and fundus images were captured using wide-field digital fundus camera (Retcam 3). Results Out of the 402 screened preterm babies, 237 (59%) cases had ROP, among whom 101 (42.6%) had stage 1, 114 (48.1%) had stage 2, 12 (5.1%) had stage 3, 10 (4.2%) had aggressive posterior retinopathy, and 24 (10.1%) presented with plus disease. GA, BW, oxygen therapy, sepsis, multiple birth, and cesarean section were factors found to be significantly associated with the disease. Conclusion ROP occurred in 59% of all screened preterm babies. The main risk factors for the development of ROP were GA, BW, oxygen therapy, sepsis, multiple birth, and cesarean section

Safety and efficacy of cetuximab-chemotherapy combination in Saudi patients with metastatic colorectal cancer

Background: Cetuximab-based combination chemotherapy (CBCC) proved safe and effective as second-line strategy for metastatic colorectal cancer (mCRC). This prospective phase-II study was designed to assess the efficacy and safety of CBCC as first-, second- or third-line among Saudi patients with mCRC. Materials and Methods: Patients with mCRC were offered CBCC to assess time-to-disease progression (TTP), response rate and duration, overall survival (OS) and safety. Results: Nineteen patients were eligible and their median age was 51 years. Seven patients received CBCC as first-line and 12 as second- or third-line. Responses: 11 (58%) partial responses, 5 (26%) stable disease and 3 (16%) disease progressions. The median response duration was 4.3 months [95% confidence interval (CI): 3.4-5.2 months]. The median TTP was 6.8 months (95% CI: 2-13.9 months) for all 19 patients compared to 9.3 months (95% CI: 3.9-14.6 months) for the seven patients who received CBCC as first-line. The median OS for the entire population was 12.3 months (95% CI could not be determined). On the other hand, while the median OS for those who received CBCC as first-line have not been reached, the median OS for those who received CBCC after failure of other salvage therapies was 12.3 months (95% CI: 3.2-21.4 months). CBCC was generally tolerable. One patient had a severe hypersensitivity reaction and another fatal cardiac arrest. Conclusion: CBCC is active with an acceptable safety profile. Until results from phase-III clinical trials are available, using CBCC as first-line is probably justified

MOLECULAR EPIDEMIOLOGICAL STUDY ON PESTE DES PETITS RUMINANTS IN EGYPT 2015

Peste des petits ruminants (PPR) is one of highly contagious viral diseases of small ruminants with high economic losses due to the high morbidity and mortality. In Egypt, PPR in the last 10 years re-emerged again with high mortality in sheep flocks. There is no much data regarding the circulating Peste des petits ruminants’ virus and the epidemiological distribution in small ruminants. The study was carried out on a sheep flock of 50 rams aged of 9-12 months with clinical signs suggestive to PPR infection (fever, erosions of the buccal mucosa, pneumonia, diarrhea high morbidity and mortality). Buffy coat and lymph nodes from diseased and dead animals were sent for diagnosis and molecular diagnosis was confirmed using RT-PCR with specific primers targeting three genes; nucleo-capsid (N), fusion (F), and hemagglutinin (H). Sequencing and phylogenetic analysis was carried out on the PCR products and revealed that, the circulating virus is belonged to lineage IV along with Ethiopian strain. Key words: peste des petits ruminants; molecular; epidemiological; diagnosis; Egypt   MOLEKULARNA EPIDEMIOLOŠKA ŠTUDIJA KUGE DROBNICE V EGIPTU LETA 2015 Povzetek: Kuga drobnice (PPR; iz angl. peste des petits) je ena izmed zelo nalezljivih virusnih bolezni malih prežvekovalcev, ki zaradi visoke obolevnosti in umrljivosti povzroča visoke gospodarske izgube. V Egiptu se je v zadnjih desetih letih PPR znova pojavila z visoko smrtnostjo pri ovcah. O kugi drobnice in epidemiologiji te bolezni pri malih prežvekovalcih v literaturi ne najdemo veliko podatkov. Opisana raziskava je bila opravljena v čredi 50 ovnov, starih od 9 do 12 mesecev, s kliničnimi znaki, ki so kazali na prisotnost bolezni PPR (zvišana telesna temperatura, erozije ustne sluznice, pljučnica, driska, visoka obolevnost in smrtnost). Za natančno diagnosticiranje bolezni je bil uporabljen del krvi, pridobljen s centrifugiranjem, ki vsebuje veliko levkocitov in trombocitov (angl. Buffy coat) in bezgavke obolelih in mrtvih ovnov. Z uporabo specifičnih oligonukleotidov za določanje prisotnosti nukleotidne (N), fuzijske (F) in hemaglutininske (H). beljakovine v reakciji RT PCR smo na molekularnem nivoju potrdili prisotnost okužbe s povzročiteljem PPR. Analiza zaporedja genov in filogenetske analize so bile izvedene na produktih analize PCR, pri tem pa smo ugotovili, da virus pripada liniji IV skupaj z etiopijskim sevom. Ključne besede: kuga drobnice; molekularna diagnostika; epidemiologija; Egip

Past, Present and Future of Colorectal Cancer in the Kingdom of Saudi Arabia

<b>Background/Aims:</b> The crude frequency of colorectal cancer (CRC) is second to breast cancer in the Kingdom of Saudi Arabia (KSA). To assess the future burden of CRC in the country, we designed a model that takes into consideration the recent lifestyle pattern and the growth and aging of the population. <b> Methods:</b> We compared CRC statistics for KSA (using data from the National Cancer Registry) with that from the Surveillance, Epidemiology and End Results (SEER) databases of the United States of America (USA). We used the Joinpoint regression program to identify changes in secular trends, while the GLOBOCAN 2002 software was used to project future incidence and mortality. <b> Results:</b> Between 1994 and 2003, age-standardized rates (ASRs) for CRC in KSA almost doubled, as compared to a nonsignificant decline in USA. Between 2001 and 2003, while the annual percent change (APC) of CRC incidence in the USA showed a nonsignificant decrease in females, APC in Saudi females showed a nonsignificant rise of six percent. On the other hand, the rising incidence among Saudi males, during the years 1999 to 2003, was significant, with an APC of 20.5&#x0025;. The projection model suggested that the incidence of CRC in KSA could increase fourfold in both genders by the year 2030. <b> Conclusions:</b> In KSA, the present and expected increase in CRC rates is alarming. Pragmatic recommendations to face that challenge are discussed. The present work could serve as a model to study other prevalent types of cancer, particularly in developing countries