Harnessing the Phytase Production Potential of Soil-Borne Fungi from Wastewater Irrigated Fields Based on Eco-Cultural Optimization under Shake Flask Method

Indigenous fungi present in agricultural soils could have synchronized their inherent potentials to the local climatic conditions. Therefore, the fungi resident in the untreated wastewater irrigated agricultural field might develop their potential for producing various enzymes to handle the induced full organic load from domestic wastewater and toxic chemicals from the textile industry. Around 53 various fungal isolates were grown and separated from the soil samples from these sites through soil dilution, soil-culture plate, and soil-culture plate methods. All the purified fungi were subjected to a phosphatase production test, and only 13 fungal strains were selected as phosphatase producers. Among them, only five fungi identified as Aspergillus niger, Aspergillus flavus, Aspergillus fumigatus, Penicillium purourogenum, and Mucor rouxii based on morphological similarities, showing higher phosphate solubilizing indices, were utilized for eco-cultural fine-tuning to harness their full production potential under shake flask (SF) method. Among various media, orchestral tuning, 200 µM sodium phytate as substrate with 1.5 mL of inoculum size of the fungi, pH 7, temperature 30 °C, glucose, and ammonium nitrate as carbon and nitrogen additive with seven days of incubation were found to be the most appropriate cultural conditions to harness the phytase production potential of the selected fungi. Aspergillus niger and Aspergillus flavus showed initial phytase activity (5.2 Units/mL, 4.8 Units/mL) and phytase specific activity (2.85, 2.65 Units/mL per mg protein) during screening to be enhanced up to 17 ± 0.033 (Units/mL), 16 ± 0.033 (Units/mL) and (13 ± 0.012), 10 ± 0.066 (Units/mL per mg protein), respectively, with the above-mentioned conditions. The phytase enzyme produced from these fungi were found to be almost stable for a wide range of pH (4–8); temperature (20–60 °C); insensitive to Ca2+ and Mg2+ ions, and EDTA, Ni2+, and Ba2+ inhibitors but highly sensitive to Mn2+, Cu2+, and Zn2+ ions, and Co2+, Cr3+, Al3+, Fe2+ and Ag1+ inhibitors. It was suggested that both phytase-producing strains of A. niger and A. flavus or their crude phytase enzymes might be good candidates for application in soils to release phosphates from phytate and a possible valuable substitute of phosphate fertilizers.

Hydraulic Fracturing at Clair: Unlocking the Potential of Europe's Largest Reservoir

The Greater Clair area, Europe's largest oilfield, has two existing platforms, Clair Phase 1 and Clair Ridge, on production with future potential for a third platform targeting undeveloped Lower Clair Group to the South of Ph1. Clair Phase 1 was the initial development of Clair, targeting Lower Clair Group (LCG) reservoir consisting of a complex Devonian sandstone in six units. Most Phase 1 wells penetrated relatively good quality reservoir enhanced by natural fractures, while more recently Clair Ridge wells took a similar approach targeting natural fractures, however that strategy is continually being evaluated. In some areas however low matrix quality and lack of natural fractures were the dominant characteristics resulting in lower production rates. A brief comparison of the range of production outcomes will be presented, including potential downsides of reliance on natural fractures. Given the large oil volumes in areas of known poorer rock quality, alongside variable production results, a hydraulic fracturing trial was initiated in 2017. Well 206/08-A23 (A23) targeted previously under-developed, poor-quality Unit VI within the Phase 1 Graben area where natural fractures are absent. A pre-frac production test established baseline production of 900BOPD in December 2018. The A23 objectives included subsequent hydraulically fracturing the well to test this techniques ability to unlock production from tight, matrix dominated formation. Detailed analysis of core, log and limited vertical well fracturing data (from initial fracturing trials of 1980's vintage), yielded robust designs. Key challenges included overcoming very low KV/KH ratios with fracture heights exceeding 300ft. The resulting detailed designs provided consistent and predictable hydraulic fracturing execution in A23 in 2019, including placement of four planned 500klbs treatments combined with coil clean-outs after each stage to unload solids and fluids from the well. Initial fracture designs were conservative in terms of pad and proppant scheduling which, alongside learnings around operational logistics offshore West of Shetlands and completion design, offer significant optimisations for future hydraulic fractures. Post frac A23 became the highest non-natural fractured producer across Clair. Initially a six-fold production increase was observed with monitoring of transient production ongoing. Tracer analysis confirmed production contribution from all zones. Proving fracturing technology brings opportunities to unlock poorer Phase 1 and Ridge reservoir areas. Additionally, significant portions of the undeveloped Lower Clair Group to the South of Ph1 comprises lower permeability reservoir with higher viscosity oil and reduced natural fracture presence. Hydraulic fracturing is therefore a crucial completion technique for developing this lower quality reservoir and brings significant value enhancement to the project. Efficient delivery of numerous large fractures in a harsh offshore environment West of Shetlands presents significant challenges. The influence of how the A23 fracturing results and learnings are guiding future hydraulic fracturing concept are detailed, including optimising platform engineering design to facilitate efficient fracturing operations while maintaining the required productivity in this challenging scenario.

Determination of swithgrass (Panicum virgatum L.) seeds quality

Purpose. Developing a method for determination of the laboratory seed germination that could reduce the biological dormancy period and, accordingly, increase the intensity of germination. Methods. Laboratory, measuring and weighing, mathematical and statistical. Results. Cooling switchgrass seeds at a temperature of 10°C for 7 days on average for three years did not lead to a decrease in germination energy and germination compared to cooling for 14 days. These indexes were almost the same and amounted to 74 and 76%, 73 and 75%, respectively. There were no significant deviations in germination energy and seed germination over the years of research as affected by duration of the cool period. The production test of the developed method, carried out in the accredited control and measuring laboratory, confirmed the obtained in the laboratory results. Conclusions. Seed germination by an improved method, when pre-cooling is carried out for 7 instead of 14 days and counting of germinated seeds on 15th day instead of 20th, has reduced the time to determine germination by 13 days without reducing the quality of analysis. It is advisable to determine the 1000-seed weight in one of three ways, but the most accurate is the third way, i.e. counting the seeds in 10 repetitions.

Disinfection of environmental objects against coccidia oocysts in broiler chickens

The purpose of the research is developing a method for disinfection of environmental objects against coccidia oocysts in broiler chickens.Materials and methods. At the VNIIP – FSC VIEV vivarium, a bioassay test was performed to experimentally infect 60 chickens aged 14 days which were divided into six equivalent groups of 10 birds each and kept isolated in cages. Chickens from the first, second and third groups were administered orally, using a micropipette, 1 ml of an Eimeria oocyst suspension treated with 4, 5 and 6% solutions of the combined eimeriocide agent. Chickens from the fourth group were administered 1 ml of Eimeria oocyst suspension treated with 4% phenol solution (base drug). Chickens from the fifth group received 1 ml of a buffered solution and were used as a noninfected control. Chickens from the sixth group received 1 ml of suspension containing 2000 oocysts/mL and were used as an infected control. The efficacy of disinfection with eimeriocide and the basic drug was determined based on the percentage of decrease in the recovery of Eimeria oocysts after being exposed to drugs as compared to chickens of the infected control. The efficacy of 5% eimeriocide against poultry coccidia oocysts in a production test was determined empirically with the set of oocysts on control sites as compared with the basic drug on a poultry farm in the Moscow Region.Results and discussion. The intense-effectiveness of 4% eimeriocide against coccidia oocysts was 99.31%, and the 5 and 6% combined agent showed 100% efficacy. The basic drug, 4% phenol showed 74.65% intense-effectiveness. The results obtained in the production test of 5% eimeriocide at a dose of 0.5 l per 1 m2 with a 2 hour-exposure indicate its high efficacy for disinfection against coccidia oocysts in broiler chickens. The intense-effectiveness was 97.25% versus 59.03% efficacy of the base drug, phenol.

An Optimality Theory-Based Approach into the Phonotactic Constraints of English Spoken by Broadcasters in Nigeria

<p style="text-align: justify;">One of the observations in the English spoken particularly in Nigeria is phonotactic constraints. The constraints pin down the generalization which guide the articulation of sequences of phonemes. The paper examines the patterns of English consonant clusters articulation of Nigerian broadcasters in the onset and coda positions against Received Pronunciation English. The study is conducted within the framework of Optimality Theory (henceforth OT). 20 radio and television broadcasters from 4 electronic media were selected as participants. Data were obtained by means of production test and OT was employed for the analysis. The findings revealed that the participants used epenthetic vowels to break-up consonants clusters in the onset and consonant deletion to simplify clusters in the coda. The subjects’ productions can be captured by ranking Markedness constraints higher than Faithfulness constraints.</p>

Effects of task repetition with written corrective feedback on the knowledge and written accuracy of learners with different prior knowledge of the structure

Previous task repetition studies have largely overlooked the second language learners’ development of linguistic knowledge as well as written accuracy. Furthermore, sufficient attention has not been paid to the role of written corrective feedback (WCF) in task repetition to reinforce attention to form. Moreover, studies exploring task repetition effects on learners with different prior knowledge of the target structure are rare. This study attempted to bridge these lacunas. Seventy-nine upper-intermediate learners in Iran were divided into four groups: task repetition with no feedback (TR), task repetition with metalinguistic feedback (TR+M), task repetition with direct feedback (TR+D), and task repetition with mixed direct metalinguistic feedback (TR+DM). All groups performed an error correction test that measured explicit knowledge, an elicited imitation test that tapped automatized explicit knowledge, and a picture-cued written production test that measured written accuracy. Participants performed a dictogloss task and received WCF before repeating the same task. Subsequently, they performed another dictogloss task with different content. Results revealed that the +Prior Knowledge learners in the TR+DM group gained explicit knowledge and proved slightly better than the TR+D regarding written accuracy. None of the groups, however, could develop automatized explicit knowledge.

Integration Success Story in Shilaif Shale Oil from Vertical Pilot to Horizontal

The development of unconventional target in the Shilaif formation is in line with the Unconventional objective towards adding to ADNOC reserves. For future optimization of development plans, it is of utmost importance to understand and test and therefore prove the productivity of the future Unconventional Horizontal Oil wells. The Shilaif formation was deposited in a deeper water intrashelf basin with thicknesses varying from 600 to 800 ft from deep basin to slope respectively. The formation is subdivided into 3 main composite sequences each with separate source and clean tight carbonates. The well under consideration (Well A-V for the vertical pilot and Well A-H for the horizontal wellbore) was drilled on purpose in a deep synclinal area to access the best possible oil generation and maturity in these shale Oil plays. Due to the stacked nature of these thick high-quality reservoirs, a pilot well is drilled to perform reservoir characterization and test hydrocarbon type and potential from each bench. Fracturing and testing are performed in each reservoir layer for the primary purpose to evaluate and collect key fracturing and reservoir parameter required to calibrate petrophysical and geomechanical model, landing target optimization and ultimately for the design of the development plan of this stacked play. Frac height, reservoir fluid composition and deliverability, pore pressure are among key data collected. The landing point selected based on the comprehensive unconventional core analysis integrated with petrophysical and geomechanical outcomes using post vertical frac and test results. Well A-H was drilled as a sidetrack from the pilot hole Well A-V. This lateral section was logged with LWD Triple Combo while Resistivity Image was acquired on WL. Based on the logging data the well stayed in the target Layer / formation, cutting analysis data for XRD and TOC was integrated with the petrophysical results in A-H well. Production test results from subject were among the highest rate seen during exploration and appraisal of this unconventional oil plays and compete with the current commercial top tier analog unconventional oil plays. Achieving those results in such early exploration phases is huge milestone for ADNOC unconventional exploration journey in UAE and sign of promising future development.

An Integrated and Digitalized Approach to Reduce the Well Failure Index During Covid-19 Global Pandemic in Shushufindi Field

The Covid-19 pandemic is an unprecedented condition to the global economy including the oil & gas industry. The ability to adapt to the imposed changes, requires creativity, innovation, digitalization of processes, and resilience. This work will show a novel integrated approach around four pillars which had improved operation efficiency and brought monetary value during a challenging 2020 in Shushufindi field, Ecuador. The first pillar is new technology adoption. This aims to extend run life of critical equipment resulting in a higher well productive time. Examples of adopted technology: Chrome-enrich tubulars, downhole microcaps chemical deployment, de-sander and multiphase/extended gas handler. The second pillar is the P3 process (Pre-Pulling-Post) to quickly and effectively find the root cause of well failure that leads to definite remedial action. Digital enabler is the third pillar, its value come from reducing operational downtime and risk by using real-time surveillance capability, remote control, and data intelligence. The final pillar is to re-establish an effective communication with all stakeholders. Various dashboards have been developed in order to provide the big picture of actual field condition in quickly manner as well as implementation of ESP real time surveillance & diagnostics, real time multiphase production test, and chemical treatment automation. Workshops, online technical, and service quality meetings are regularly conducted to ensure that recommendations and opportunities can be executed properly including contractual negotiations to enable new technology implementation. Despite all the restrictions during covid-19 pandemic and some force majeures in 2020, this integrated and digitalized approach has resulted an outstanding outcome: Well failure index reduced from 0.62 in 2019 to 0.41 in 2020; Production deferment related to well failure declined significantly from 2,420 bopd in 2019 to 1,259 bopd in 2020, which translate in savings of $16.8 million dollars. In addition to that, there was a reduction on operational cost from $26.3 million dollars in 2019 to $15.2 million dollars in 2020. This proven initiative has been supported and recognized by all stakeholders. Some new technologies and digitalization projects are in the process to be implemented in Shushufindi field as part of Ecuador digital strategy 2022. This successful integrated and digitalized approach can be adopted in other fields and will generate a huge business impact.

An Innovative Approach to Install Production String with ESP to Avoid Productivity Impairment in Multistage Fractured Horizontal Well

Objectives/Scope Generally, tight reservoirs require hydraulic fracturing to enhance and sustain hydrocarbon production. However, fracturing requires frac string with bigger Internal Diameter (ID) to minimize frictional losses during hydraulic fracturing operation. This string ID may not be suitable to provide optimum Vertical Lift Performance (VLP) during production phase, particularly in oil wells. Therefore, it is required to replace the frac string with production string of smaller ID. Occasionally, artificial lift also becomes essential to overcome VLP issues in future due to progressive water production and declining reservoir pressure. Methods, Procedures, Process Completion replacement often causes reservoir damage due to killing operation, which can be removed in conventional carbonate reservoirs by matrix stimulation. However, formation damage removal is difficult in hydraulically fractured tight carbonate and sandstone reservoirs. Preventive measures become essential to avoid productivity impairment particularly in hydraulically fractured reservoirs. Different preventative options are proposed and reviewed to isolate reservoir with their advantages and disadvantages. After comprehensive studies and risk assessments, an innovative modification in the completion plan was introduced and finalized. This plan includes production string with Electrical Submersible Pump (ESP) to improve VLP. This completion provides full accessibility intervention job, which may be required for reservoir monitoring and surveillance in future. Results, Observations, Conclusions A comprehensive production test is performed to evaluate and compare the testing results of pre and post workover. Testing results show there is no impairment in productivity of the reservoir, which is avoided in workover process by isolating reservoir section. This paper summarizes the completion design process, selection criteria, challenges, and lessons learnt during design and execution phases. This technique will provide the guidelines for installation of the Production string/ESP in hydraulically fractured reservoir without productivity impairment. Novel/Additive Information With modified design, the reservoir is isolated from wellbore and completion with ESP is run successfully without killing reservoir section. Underbalance conditions are achieved prior to establishing communication between reservoir and wellbore.