bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation Barrier Valves Installed Successfully in Deepwater Gulf of Guinea
Authors: Carpenter Chris
Published: May 2019

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper OTC 28453, “Egina Deepwater Development: Isolation-Barrier-Valve Case Study,” by G. Forrest, C. Morand, K. Johnson, and V. Okengwu, Halliburton, and V.  Chaloupka, SPE, Total, prepared for the 2018 Offshore Technology Conference Asia, Kuala Lumpur, 20–23 March. The paper has not been peer reviewed. Copyright 2018 Offshore Technology Conference. Reproduced by permission.

A major operator manages multiple deepwater projects in the Gulf of Guinea. This paper describes one of these, a recent 44-well project. The operator required an ISO 28781-qualified bidirectional subsurface isolation barrier valve (IBV) to be installed in each well. This paper presents the results of the IBV deployment in the field.

Introduction

The Egina field was discovered in 2003 in Oil Mining Lease 130 located in deep water (1150–1750 m) approximately 200 km offshore Port Harcourt, Nigeria.

Subsurface IBVs have become commonplace in lower-sandface-completion installations. The potential time and operational cost savings are well understood. However, industry concerns remain regarding the ability of these devices to operate reliably in demanding wellbore conditions.

The primary challenges for this project were

Deviated wells with horizontal drains, high dogleg severity, and azimuth changes

Isolation of different reservoirs along each drain

Faults

Running the upper completion in sieved nonaqueous-based mud (NABM)

Well-Control Philosophy and Barrier Requirements

General philosophies and requirements for well control—including the overall principles for well barriers, kill methods, and project-specific needs—require the following with respect to barriers:

Can be pressure-tested

Location and status can be known at all times

Can be re-established in a short period of time

Can operate in the environment despite challenges related to pressures, temperatures, and fluids

The integrity of a barrier can be verified by pressure-testing to working pressure in the direction of flow when possible. These tests can also be run in the reverse direction. After completion and tree installation, tests are conducted using available well pressure.

IBV Design Update. The IBV design in question (Fig. 1) was first run in west Africa in 2008 as a result of an extensive qualification and testing program aimed at improving upon its predecessor. The new IBV improved debris tolerance to meet ISO 28781 regulatory requirements. Enhancements also included increased differential opening pressure, simplified operating and workshop-testing procedures, removal of the transit pin, and increased opening force.
Energy, Environment, and Social Development: What If You Had No Modern Energy? The Realities of Solving Energy Poverty
Authors: Alnuaim Sami
Published: May 2019

President's column

Hurricane Harvey gave many SPE members in Houston at least a few days’ experience of life without electricity. Most of us find it hard to imagine what life would be like without the access to energy that we take for granted—the flip of a light switch, heating something in the microwave, or climate control in our homes. Yet nearly 1 billion people on our planet go through their days without electric lights, refrigeration, heating/cooling, clean fuel for cooking food indoors, and more. Those who rely on wood, peat, or dung for cooking spend hours each day gathering fuel. The gatherers are often the women and children, precluding their access to education and other opportunities. Use of kerosene for lighting has been linked to lung cancer, pneumonia, heart disease, and other health problems. Lamps are easily knocked over and start fires. A lack of access to electricity has ripple effects across many aspects of people’s lives, health, and safety.

The International Energy Agency (IEA) reports that in 2017 more than 120 million people worldwide gained access to electricity, causing the total number of people without access to fall below 1 billion for the first time ever. IEA is expecting this reduction in energy poverty to double when 2018 data are available. The United Nations is targeting zero energy poverty by 2030. The gains during 2017 are largely attributable to a significant government effort in India to bring electricity to all of its villages and progress in a few African countries. Despite these gains, more than 55% of people in Sub-Saharan Africa and around 9% of those in Asia still lack access to the benefits of electricity. In 15 African countries, the percentage of the population without access to electricity is 75% or more.

Where did the electricity for those 120 million new consumers come from? Since 2000, according to IEA, 26% of this additional access to electricity has come from natural gas, and to a lesser extent, oil. Another 45% has come from coal (commonly used for electricity in India). Since 2012, renewables have grown in the mix and now constitute 34% of new electric connections in developing areas, led by solar power. Those who argue we should stop using all fossil fuels immediately may not realize that they would be limiting the opportunity of those without power to improve their standard of living.

Progress on ensuring access to clean fuels for cooking has been much slower. IEA estimates that 2.8 billion people lack access to modern cooking fuels, virtually unchanged from 2000. China and Indonesia have made progress through policies encouraging use of liquefied petroleum gas (LPG), natural gas, and electricity for cooking. IEA reports that 2.5 billion people cook with traditional biomass sources, while another 120 million use kerosene and 170 million use coal for cooking. Natural gas, LPG, and natural gas liquids have the potential for replacing these sources, with significant environmental and health benefits as well.
New Operators, Well Designs Drive Record Gas Production in Haynesville
Authors: Jacobs Trent
Published: May 2019

The Haynesville Shale might be the greatest comeback story of the US shale revolution.

At one point in 2016, there were just 13 active rigs in the dry-gas play that stretches between Louisiana and Texas. That figure has increased fourfold to today and, in April, the Haynesville set a new production record of 10.5 Bcf/D—the strongest output since 2011, per the US Department of Energy (DOE).

The resurgence has been led not by the large operators who initially put the Haynesville on the map, but by a group of private equity-backed operators that entered the play within the last few years. Their momentum has been driven by liquefied natural gas (LNG) facilities that began exporting the product from the US Gulf Coast in 2016.

Petroleum engineers have also moved the needle by creating a class of horizontal wells that look nothing like what the region has seen before in terms of productivity.

“I think that over the past 3 or 4 years, the understanding of optimal frac design and the selection of the targets has evolved quite dramatically,” said Artem Abramov, the head of shale research for Rystad Energy in Oslo.

The nearly 300 wells that were brought online in the Haynesville during 2017 have produced a cumulative average of 3.6 Bcf. They continue to generate an average of 8.5 MMcf/D, according to public data compiled by ShaleProfile.

This is a marked improvement over 2015 vintage wells that managed only 1.5 MMcf/D after reaching the same cumulative production point. In terms of long-tail production, this is an increase of more than 450%.

One of the most critical factors behind the improved recovery is the increased use of proppant in horizontal wells. Thanks to lower prices made possible by the in-basin mine trend taking hold across the US shale sector, operators can afford to place two or three times the amount of sand into Haynesville’s tight-rock system than they were prior to 2016.

Abramov remarked that this development has effectively “re-established it as a completely new play.”

Too Much of a Good Thing

Rig counts have remained steady at around an average of 55 since the start of the year but the region is seeing more completion activity and has become one of the fastest-growing demand centers for hydraulic fracturing crews in the US. As the race to reawaken the sleeping giant continues on, there are concerns that too much production could harm the play’s economic standing.

Calgary-based RS Energy Group (RSEG) recently looked at the issue and found that takeaway capacity may hit a wall as early as this summer, possibly curtailing drilling plans for the rest of the year.

“It’s not a Haynesville constraint in isolation,” explained Trevor Sloan, an executive director and co-head of research at RSEG. “Rather, Haynesville producers share common routes to coastal demand centers—including LNG facilities—with northeast producers, and the midcontinent for that matter. Potential from all those basins could cause some congestion on routes south.”
Offshore Enters a New Era
Authors: Wilson Adam , Whitfield Stephen , Jacobs Trent , Donnelly John
Published: May 2019

2019 OTC review

Digitalization and automation were key topics in the panel and technical sessions at this year’s Offshore Technology Conference (OTC) as the iconic event celebrated its 50th anniversary. More than 59,000 attendees participated in the conference, which was held 6–9 May in Houston. 

OTC launched its golden anniversary with a wide-ranging panel discussion on the current viability of the offshore sector and how digitalization will change it in the future.

Total’s Energy Outlook 2040 proposes two distinct scenarios of the energy future: a momentum scenario, in which oil demand is dominated by transportation and petrochemicals, and a rupture scenario, which sees a massive shift in public policy and the growth of renewables. Either way, “our industry has a major role to play in climate change issues,” said Arnaud Breuillac, president of exploration and production for Total.

The global energy mix is changing, he said, but the question is how rapidly, especially regarding use of electric vehicles and the growth of electrification in developing countries. Given the projected population rise and the fact that 1.5 billion people do not have access to energy now, increased use of natural gas and renewables is the “right approach to stabilize the energy system,” Breuillac said. The 21st century will likely be the “century of electricity,” he added.

“It is clear that the pace of change does not lie entirely in our hands,” he said about the use of hydrocarbons in the future, but will be influenced by the public and policymakers as well. For now, Total is pursuing projects on the low end of the cost curve while trying to reduce its carbon footprint from production to customer delivery.

Whether the industry should pursue a future of reduced hydrocarbon production and use appears to be a dilemma, said panel moderator Scott Tinker, director of the Bureau of Economic Geology at The University of Texas at Austin. If climate change is the worst problem, then reduced hydrocarbon use could be part of the solution; but if poverty is the globe’s biggest issue, then hydrocarbons are undoubtedly part of the solution.

Although the industry “does produce a lot of CO2,” Tinker said, access to readily available and affordable energy also alleviates hunger and provides clothing, shelter, and clean water, and allows access to education, health care, and medical services, among other things. Offering more perspective, Tinker noted that although there is a lot of talk about the growth in wind and power for energy, their use is but a fraction of demand for oil, natural gas, and coal. Over the past several decades, carbon emissions in the US and Europe have been flat to slightly down, while emissions in Asia have grown sharply, he said.
Factory-Model Approach Improves Performance of Coiled-Tubing Drillout
Authors: Feder Judy
Published: May 2019

This article, written by JPT Technology Editor Judy Feder, contains highlights of paper SPE 191689, “Factory-Model Approach for Successful Coil-Tubing-Unit Drillout Operations in Unconventional Wells,” by Jesus Barraza, SPE, and Chris Champeaux, SPE, Chevron; Heath Myatt, SPE, and Kyle Lamon, C&J Energy Services; Ryan Bowland, Spartan Energy Services; Troy Bishop, SPE, and Jerry Noles, SPE, Coil Chem; and Rocky Garlow, RGC Consulting, prepared for presentation at the 2019 SPE Hydraulic Fracturing Technology Conference and Exhibition, The Woodlands, Texas, USA, 5–7 February. The paper has not been peer reviewed.

As drilling and fracturing operations improve, there is a need to adapt current coiled-tubing (CT) drillout processes to a more fit-for-purpose approach applicable in any area, regardless of lateral length, number of plugs, and reservoir target. This paper presents a factory-model approach to improving CT drillout performance that has been used successfully for more than 3 years and has become standard practice. The paper includes detailed discussion of the methodology used to create a successful, repeatable, and operationally safe process; field case studies and results; and engineering, design, and implementation of new technologies to improve the process.

Introduction

CT practices have become increasingly effective in plug drillout operations by reducing the operational cost, environmental exposure, and time to production. Techniques for no-wiper or short trips and plug milling, added benefits from extended-reach bottomhole assemblies (BHAs), and improved fluid-system monitoring methods have helped enhance overall performance. However, there are still components within each of these techniques that can be evaluated.

Background and Methodology Results of a thorough evaluation of the CT drillout process revealed that the factors with the greatest influence on improving performance included the following:

Wellbore trajectory

Plug type

CT size

BHA selection

Fluid-rheology quality assurance/quality control (QA/QC)

Real-time modeling

Communication

Wellbore trajectory is an important factor because it has a major effect on the ability of a CT unit to reach plug-back total depth. High tortuosity in the lateral section can cause plug parts and sand to settle on the low side of the wellbore, making adequate cleaning of the hole by increasing overall friction difficult.

Proper plug type and design serve two purposes: to provide a barrier between stages during hydraulic-fracturing operations and to be easily removed from the wellbore during drillout. Ideally, a fully composite plug should be selected because the lower specific gravity of the material aids in removal.

The proper CT size can lead to a more-successful drillout because it allows for higher pump rates, leading to better hole cleaning. Additionally, larger outer-diameter CT (23/8 in. or greater) ensures sufficient weight on bit (WOB) in the toe of longer laterals to reduce friction pressure and protect against helical buckling.
Technology Focus: EOR Operations (June 2019)
Authors: Goodyear Stephen
Published: May 2019

Technology Focus

In the March edition of JPT, a series of articles looked at professional pride. Reading them made me reflect on my own career and consider what have been my best moments in the industry (to date!). Back in the 1990s, I was part of an EOR group providing technical advice to the UK Department of Energy in sup-port of their review and approval of field-development plans for the UK sector of the North Sea. The Captain field was under consideration for development. The viscous oil made it a challenging development, requiring waterflooding with horizontal injectors and producers and lifting with electrical submersible pumps.

I led an assessment of EOR for the UK Department of Energy showing that there were potentially viable polymer-injection strategies that could give substantial additional economic recovery. The Department of Energy approved the basic waterflood development but, on the basis of my team’s work, required some minimum preinvestment in facilities to enable subsequent polymer injection, including a polymer line in the bundle from the floating production storage and offloading vessel to the wellhead platform.

These facilities now have been used in very successful polymer-injection pilots, with the first results published last year. An excellent response is reported, showing that polymer can recover more oil more quickly than waterflooding. The current operator notes that the foresight of including the front-end provisions enabled the timely implementation of polymer flooding.

This is one of my best moments: to have made the technical case for polymer flooding and to see the fruits of this several decades later. As is so often the case in our industry, my contribution stands alongside those of many others in the intervening years who have made the EOR journey for the Captain field possible and now a reality.

Recommended additional reading at OnePetro: www.onepetro.org.

SPE 190248 Miscible Hydrocarbon Gas/Oil Gravity-Drainage Pilot in the Yates Field Unit by R. Valdez, Kinder Morgan, et al.

SPE 190306 An Update on Full-Field Implementation of Chemical Flooding in Daqing Oil Field, China, and Its Future by Shize Yin, Missouri University of Science and Technology, et al.

SPE 190472 Polymer-Injection Pilots in Bhagyam Oil Field and Full-Field Polymer-Development Planning by Vivek Shankar, Cairn Oil and Gas, et al.
Computational Prediction of the Isoform Specificity of Cytochrome P450 Substrates by an Improved Bayesian Method
Authors: Dai Hao , Zheng Yu-Xi , Shan Xiao-Qi , Chu Yan-Yi , Wang Wei , Xiong Yi , Wei Dong-Qing
Published: May 2019

Cytochrome P450 (CYP) is the most important drug-metabolizing enzyme in human beings. Each CYP isoform is able to metabolize a large number of compounds, and if patients take more than one drugs during the treatment, it is possible that some drugs would be metabolized by the same CYP isoform, leading to potential drug-drug interactions and side effects. Therefore, it is necessary to investigate the isoform specificity of CYP substrates. In this study, we constructed a data set consisting of 10 major CYP isoforms associated with 776 substrates, and used machine learning methods to construct the predictive models based on the features of structural and physicochemical properties of substrates. We also proposed a new method called Improved Bayesian method, which is suitable for small data sets and is able to construct more stable and accurate predictive models compared with other traditional machine learning models. Based on this method, the predictive performance of our method got the accuracy of 86% for the independent test, which was significantly better to the existing models. We believe that our proposed method will facilitate the understanding of drug metabolisms and help the large-scale analysis of drug-drug interactions.
The Epidemiology of Syphilis in the Volta Region of Ghana: A Five-Year Multisite Parallel Population-Based Analysis vis-à-vis the Sentinel Survey
Authors: Lokpo Sylvester Yao , Owusu-Dabo Ellis , Deku John Gameli , Orish Verner Ndudiri , Kye-Duodu Gideon , Ussher Francis Abeku , Boakye Thomas , Adigbli Daniel , Ameke Louis Selasi , Fianko William Klutse , Adedze-Kpodo Robert , Letsa Henry Komla , Tashie Worlanyo , Gbormittah Noble Selorm , Kpene Godsway Edem , Osei-Yeboah James
Published: May 2019

Background: Syphilis is contagious and one of the oldest sexually transmitted infections, with great public health consequences. This study aimed to comparatively describe the five–year (2013-2017) regional epidemiology of syphilis infection using pregnant women in the Sentinel Survey and apparently healthy blood donors as proxy for the general population at the four sentinel sites in the Volta Region of Ghana. Method: We analysed retrospectively data from 17,744 prospective blood donors aged between 18 to 58 years and 7,805 pregnant women in a Sentinel Survey who fell within the 15 and 49 years age bracket at Hohoe, Ho, Tongu and Krachi-West sentinel sites in the Volta Region. Data extracted included age, gender, date of blood donation and Treponena pallidum chromatographic immunoassay results from the blood banks of the four study sites. Published reports of Sentinel Surveys conducted at the four sentinel sites from the years 2013-2017 were retrieved. Results: The cumulative five-year prevalence of syphilis infections among the pregnant women in the Sentinel Survey and prospective blood donors was 0.38% and 2.38% respectively. Site-specific prevalence for population-base/Sentinel survey was 4.6%/0.4%, 2.0%/0.2%, 1.3%/0.8 and 1.2%/0.2 for Hohoe, Ho, Krachi-West and Tongu respectively. New Syphilis infection rate was 0.31% in the sentinel survey and 2.22% in the general population. Significant gender disparity in syphilis infection exist with male preponderance. Conclusion: The regional prevalence of syphilis infection in the Sentinel Survey is lower compared to the general population. Therefore, the use of pregnant women as proxy for population estimate could lead to underestimation of the burden in the study jurisdiction.
HIV/AIDS knowledge, attitude and prevention assessment of residents in Liangshan prefecture: A cross-sectional survey
Authors: Tian Gang , Zeng Zhangrui , Long Jun , Wang Shaohua , Fu Hu , Liu Jinbo , Li Guangrong , Wang Qin
Published: May 2019

Background

The knowledge, attitude and prevention methods are crucial to avoid and prevent potential HIV infection especially in Liangshan prefecture, a high HIV infection prevalence area in China. Currently, as HIV/AIDS related studies were mainly based on sentinel surveillance groups and students, little information is known for local community residents. Our objectives were to survey HIV/AIDS related knowledge, attitude and prevention methods in these general populations to take targeted action for better prevention and control of HIV infection.

Methods

A large sample, multicounty based cross-sectional study was conducted to select seven counties randomly from 15 Yi ethnic counties plus the capital city, Xichang, for this study. A method of stratified cluster sampling was used to select 5500 local community residents in these eight counties from September 12, 2017 to October 23, 2018.

Results

Only 65.8% of respondents gave correct responses to all HIV/AIDS related knowledge and routes of transmission. The differences were significantly related to age distribution (P< 0.001), gender (P= 0.006), ethnicity (P< 0.001), educational level (P< 0.001), residence (P< 0.001) as well as fixed income or work (P< 0.001). Multicounty analysis showed the total correct answer rate of Xichang city was the highest (83.8%) in eight counties, whereas Meigu county (57.5%), Zhaojue county (50.9%) and Butuo country (48.2%) were the lowest. The positive answer rates of respondents to HIV/AIDS attitudes varied from 33.0% to 80.3%. 33.0% of the respondents wanted to have a child even though their spouse was infected with HIV, and 39.9% of the represents emerged in suicidal ideas if the HIV test results were positive. As for the prevention methods, 32.6% of the respondents did not use a condom during sexual intercourse, and 26.9% of the respondents did not approve to encourage free HIV screening.

Conclusion

It is urgent to strengthen the popularization of HIV/AIDS related knowledge and routes of transmission, and take targeted intervention and prevention policies for local community residents in Liangshan prefecture.
Molecular epidemiology of carbapenem resistant Enterobacteriaceae in Sri Lanka: First report of KPC-producing Klebsiella pneumoniae
Authors: Kumudunie Wirittamulla Gamage Maheshika , Wijesooriya Wijesooriya Rathnayaka Pathirennehalage Lakmini Inoka , Namalie Kalubowilage Dhananja , Sunil-Chandra Narapity Pathirannehalage , Wijayasinghe Yasanandana Supunsiri
Published: May 2019

Background

Extended spectrum β-lactamase producing Enterobacteriaceae (ESBL-PE) and carbapenamase producing Enterocacteriaceae (CPE) are widely disseminated globally creating a huge public health threat. Even though incidence of multidrug-resistant Enterobacteriaceae is rapidly growing, the epidemiological data regarding the occurrence of CRE in Sri Lanka is scarce. In this study, we determined the prevalence of ESBP-PE and CRE and the genetic determinants of CPE.

Methods

A total of 593 clinically significant Enterobacteriaceae was isolated from different clinical samples (urine, pus/wound, respiratory, blood, and other sterile specimens) at a tertiary care hospital in Sri Lanka from December 2017 – February 2018. Antimicrobial susceptibility and identification of ESBL-PE, CRE were done by disc diffusion method. CRE were identified to species level using a rapid identification kit and carbapenemase production was determined by modified carbapenem inactivation method. The presence of blaKPC, blaNDM, blaOXA-48-like genes were detected by PCR.

Results

The overall prevalence of ESBL-PE and CRE were found to be 26.0% and 9.6%, respectively. The rate of ESBL-PE in different sample types ranged from 18.2% to 30.8% with the highest prevalence among uropathogenic Enterobacteriaceae. The occurrence of CRE ranged from 6.7% to 20.8% with the highest prevalence among respiratory Enterobacteriaceae. CRE species identified were K. pneumoniae (80.7%), E. coli (5.3%), C. freundii (7.0%), P. rettgeri (3.5%), E. cloacae (1.7%), and E. aerogenes (1.7%). The carbapenemase production was detected in 94.7% of CRE isolates. The carbapenemases found were OXA-48-like (88.9%), NDM (14.8%), and KPC (3.7%).

Conclusions

The prevalence of CRE in Sri Lanka is alarming. Carbapenamse production was the major mechanism of carbapenem resistance and K. pneumoniae was the predominant CRE. Presence of KPC enzyme was detected in addition to the previously reported NDM and OXA-48-like carbapenamases in Sri Lanka. The rapid spread of CPE, necessitates the prompt implementation of preventive measures in Sri Lanka.
Medical Students' Perception of the Educational Environment at Al-Nahda College by using DREEM inventory
Authors: Hamdan Hamdan Z. , Ibrahim Marwa Yassin , Mohamed Rania Hessian , Ali Liza Hassan , Alhassan Yassir Mohamed , Ahmed Nasreldin Marhoum
Published: May 2019

Background: Educational environment encompasses everything that are found and occurs inside the school of Medicine. It affects the students’ ability to achieve their academic goals, feeling of academic satisfaction and well-being. Assessment of the educational environment of paramount-importance for all stake-holder, administrators and educators in the academic field. The aim of this study to measure the student perception towards the educational environment in Al-Nahda college.
Methods: This is an institutional based cross-sectional study conducted in Al-Nahda College between January and February 2018. Study population were 634 medical students. Dundee Ready Education Environment Measure (DREEM) questionnaire was used as a survey tool for this study. Students’ responses were entered to the computer and analyzed by using Statistical Package for Social Sciences (SPSS) version 24 (SPSS Inc. Chicago, IL, USA).
Results: A (83.9%) pre-clinical and (16.1%) clinical stage participated in this study from all academic levels. Three hundred and sixty (56.9%) were male students, while the rest were female (43.1%). The overall mean (SD) DREEM score in this study is 130 (34.2), which indicates more positive educational environment than negative. Likewise, students’ perception for teachers, Students’ academic self-perception, Students’ perception of atmosphere and Students’ social self-perception. However, students’ perception for learning shows negative indicator. Students’ female gender have significantly higher mean (SD) overall DREEM score than male students [136 (31.5) Vs. 129 (35.5); P= 0.008], respectively. Female scored higher than male in subclass students’ perception for teachers, Students’ academic self-perception and Students’ social self-perception, [28.8 (7.8) Vs. 27.1 (8.5); P= 0.024]; [22.2 (5.6) Vs. 21.0 (7.2); P= 0.017]; [19.8 (4.9) Vs. 18.8 (5.4); P= 0.019], respectively. The foreign students perceived the overall educational environment better than Sudanese students [135.6(31.7) Vs. 131.3 (34.8); P=0.049].
Conclusions: The educational environment is perceived positive in Al-Nahda College. Four out of five inventory subscale were perceived positive, while only students’ perception of learning sub-scale was perceived negative. Female students and non-Sudanese students perceived the educational environment better than the male students and Sudanese students. The perception of clinical students did not differ from that of pre-clinical students.
Conservation Agriculture Increases Profits in an Andean Region of South America
Authors: Delgado J. A. , Barrera Mosquera V. H. , Escudero López L. O. , Cartagena Ayala Y. E. , Alwang J. R. , Stehouwer R. C. , Arévalo Tenelema J. C. , D'Adamo Robert , Domínguez Andrade J. M. , Valverde F. , Alvarado Ochoa S. P.
Published: May 2019

Core Ideas

Erosion is decreasing the potential for food security in the Andean region.

Zero tillage would be a viable and economical practice for this region.

Adding N fertilizer increased the net economic returns by 22%.

These practices could potentially increase the income of 200,000 farmers.

The Andean region of Ecuador is critical for the country's food security; however, cultivation of high‐slope mountainous agricultural systems that experience significant precipitation is accelerating erosion of the soils and reducing the productivity and sustainability of these systems. For 5 yr we monitored tillage and crop residue management practices using a 2 × 2 factorial randomized block (Phase 1) and a 2 × 2 factorial randomized block with split plot (Phase 2) to assess the effects of tillage, crop residue management, and N fertilization on yields and economic returns. Our study found in the initial phase that for three out of the four crops zero tillage (ZT) had higher average yields than minimum tillage, and for one of these three crops, the increase was significant. Our study found in Phase 2 that when N fertilizer was added as a treatment, compared with crops that were not fertilized, yields were significantly higher in four out of five crops. Leaving the crop residue at the surface was a practice that increased the yields of one of the five crops. The higher net economic returns for Phase 1 were with ZT and with harvesting crop residue. When N was added as a treatment in Phase 2, higher net economic returns were found with ZT and residue removed and with N fertilization. Nitrogen fertilizer, crop residue removal, and zero tillage increased net economic returns by 22, 45.1, and 31.8%, respectively. There is potential to use ZT in this region of South America.
The Effect of Dry Cultivation on Yield, Water, and Iron Use Efficiency of Rice
Authors: Zhang Ya J. , Cheng Ya D. , Wang Chen , Xu Jing N. , Li Jin P. , Ye Qian , Chen He M. , Qu Ling L. , Yang Jian C.
Published: May 2019

Core Ideas

Dry cultivation reduces yield, except for the absence of significant differences between plastic film mulching cultivation and continuously flooded in paddy rice.

Dry cultivation increases Fe use efficiency and water use efficiency.

The Fe per unit mass of rice grains in upland rice is richer than that in paddy rice.

Dry cultivation is a good water conservation cultivation method in arid and semi‐arid regions with unstable irrigation sources while temperature is favorable to rice growth.

Iron is not only an essential trace element for plant growth and development, but also an indispensable trace element for humans. The objective of this study was to investigate the Fe absorption and utilization, water use efficiency (WUE) and grain yield difference between upland rice (Oryza sativa L.) cultivar Zhonghan 3 (japonica) and paddy rice cultivar Wuxiangjing 99‐8 (japonica) which were grown on the farm of the Yangzhou University under three cultivation patterns of continuously flooded condition (CF, control), plastic film mulching cultivation (PFMC), and bare cultivation (BC) under non‐flooded conditions. Compared with the CF, the grain yield was significantly lower under the PFMC for upland rice, but no significant difference was found for paddy rice, and grain yield was significantly reduced under BC for both upland rice and paddy rice. Dry cultivation lowered the Fe concentration in the rice plants and grain under the PFMC and the BC, and lowered the amount of Fe absorption in aboveground plants. Whereas, Fe use efficiency and WUE were all higher with dry cultivation. Compared with paddy rice, the Fe concentration in the whole root system of upland rice was 39.5% lower, but that in the roots was 11.3% higher at heading stage, and in the aboveground plants and rice flour was 3.4 to 11.1% higher at heading and maturity stages. The results indicate that dry cultivation is a good water conservation cultivation method in arid and semiarid regions with unstable irrigation sources while temperature is favorable to rice growth, such as in Southeast China.
Integrated Phosphorus Placement and Form for Improving Wheat Grain Yield
Authors: Lu Dianjun , Song Hang , Jiang Shangtao , Chen Xiaoqin , Wang Huoyan , Zhou Jianmin
Published: May 2019

Core Ideas

We assessed the movement capacity of different P.

Banding P fertilizer in suboptimal placement reduced wheat yield with monocalcium phosphate.

Diammonium phosphate compensated for the reduction in wheat yield due to suboptimal placement.

Banding of P can increase P availability to crops. Our objective was to determine if banding two forms of P fertilizer at multiple distances from the seed can improve wheat (Triticum aestivum L.) growth and P uptake vs. broadcast P fertilizer application. Waters‐soluble and Ca2– P concentrations in soil was greater near the point of P placement when monocalcium phosphate was used compared to diammonium phosphate, while the opposite result was found when the P diffusion distance was greater than 2 cm from the P placement. Another field experiment with four application strategies (broadcasting P, banding P under the wheat row, and banding P 5 and 12 cm from the wheat row) and two P forms was conducted over 2 yr. Banding P under the wheat row increased wheat yield and P uptake regardless of the P form compared to broadcasting P. Banding 12 cm from the row resulted in a 6.0% reduction in wheat yield for monocalcium phosphate compared to broadcasting P. Banding diammonium phosphate 5 or 12 cm from the row provided yield compensations over monocalcium phosphate. Dry matter at regreening was significantly depressed for banding 5 or 12 cm from the row with monocalcium phosphate application relative to broadcasting P, while there was compensatory growth for banding 5 cm from the row after regreening. Root length proliferated with diammonium phosphate than with monocalcium phosphate regardless of band placement. Diammonium phosphate should not be placed more than 5 cm from the row to ensure maximum P uptake potential.
Fiber Fraction Content in Legume–Grass Mixtures Treated with Mushroom Substrate and Cow Slurry
Authors: Jankowski Kazimierz , Malinowska Elżbieta
Published: May 2019

Core Ideas

Mushroom substrate application to legume grass mixtures increased neutral detergent fiber content in the forage more than slurry.

The mixture of orchard grass with alfalfa produced forage of the best quality, with regard to the content of fibre fractions.

The content of the acid detergent fiber and acid detergent lignin fractions and yielding of legume grass mixtures were higher in the forage from plots with slurry than from plots with mushroom.

The work reported here was undertaken to determine the effect of spent mushroom substrate (SMS) and cow slurry used in the cultivation of hybrid alfalfa and grass mixtures on plant productivity and dry matter nutritional value. Uncomposted waste left after growing mushrooms (Agaricus bisporus) was used. Additionally, slurry from cows with the milk yield of 6000 to 8000 litters a year was applied; the animals were housed indoors on straw bedding, with manure removed daily. The 3‐yr research study (2013–2015) was conducted in the experimental field, in east‐central Poland. Treatments were replicated three times, with plots of 3 m3 as experimental units in a split‐plot arrangement. In the experiment the main research factors were legume–grass mixtures and organic fertilizers with high organic matter content: SMS and cow slurry, used separately and in various combinations. In the experiment three plant species were involved: Medicago sativa x varia Martyn (alfalfa hybrid) ‘Tula’, Dactylis glomerata (orchard grass) ‘Bora’, and Lolium perenne L. (perennial ryegrass) ‘Info’. These species were grown as three legume–grass mixtures. The results demonstrated that SMS application to legume–grass mixtures increased NDF content in the forage more than slurry. The content of the ADF and ADL fractions and the yields of legume–grass mixtures were higher in the forage from plots with slurry than from plots with SMS. The mixture of orchard grass with alfalfa produced forage of the best quality with regard to the content of fiber fractions.
Modeled El Niño‐Southern Oscillation Effects on Grain Sorghum under Varying Irrigation Strategies and Cultural Practices
Authors: Baumhardt R.L. , Schwartz R.C. , Marek G.W , Moorhead J.E.
Published: May 2019

Core Ideas

Maturing Oceanic Niño Index identified La Niña years with less rain and yield.

Increased irrigation plus rain improved yield but water use efficiency plateaued.

Irrigation of partitioned areas with dryland improved yield independent of El Niño southern oscillation phase.

Equatorial sea surface temperatures vary systematically to cause the El Niño southern oscillation (ENSO) that produces predictable weather patterns in North America and may permit long‐range climate predictions and eventual proactive summer crop irrigation management. The declining Ogallala Aquifer in the Southern High Plains and consequently limited well capacities challenge producers to adapt cropping practices for irrigation that doesn’t meet crop water demand. Our objective was to evaluate sorghum [Sorghum bicolor (L.) Moench] yield response to ENSO climate‐informed management of cultural practices and irrigation strategies on a Pullman soil (fine, mixed, superactive, thermic Torrertic Paleustoll). We used the simulation model SORKAM and long‐term (1961–2000) weather records from Bushland, TX, classified by ENSO phase to calculate sorghum grain yields for all combinations of irrigation levels (0.0, 2.5, 3.75, or 5.0 mm d−1), planting day of year (DOY = 135, 156, 176), and cultivar maturity (early, 95 d; medium, 105 d; late, 120 d). Using the September–November Oceanic Niño Index (ONI) to identify ENSO phase, La Niña years had 50 mm less precipitation and a corresponding 14.5% reduction in overall yield to 4550 kg ha−1 for sorghum planted at 16 plants m−2 population. Late maturing cultivars and late planting led to sorghum freeze injury and reduced yields regardless of ENSO phase. While yields consistently increased with irrigation, we conclude that concentrating water to irrigate an area partitioned 2:1 or 1:1 at 3.75‐ or 5.0‐mm d−1 with complementary dryland produced >30% more grain, overall, than uniformly irrigating an area at 2.5 mm d−1.
Lower‐Leaf Removal and Nitrogen Application Programs for Flue‐Cured Tobacco Production
Authors: Finch Camden E. , Vann Matthew C. , Fisher Loren R. , Wells Randy , Brown A. Blake
Published: May 2019

Core Ideas

Lower‐leaf removal will reduce cured leaf yield but can reduce the portion of lower‐demand stalk positions

Nitrogen application after leaf removal is of limited value and is currently discouraged

If these programs are to find commercial success, a higher selling price should be offered by leaf purchasers

With a current global over‐supply of flue‐cured tobacco (Nicotiana tabacum L.), tobacco producers in North Carolina have been encouraged to remove the lowermost leaves prior to harvest due to their low value in manufactured products. The objective of this research was to compare lower‐leaf removal programs. Research was conducted in 2016 and 2017 to quantify the agronomic effects of three lower‐leaf removal programs (0, 4, and 8 leaves plant−1) and the subsequent delivery of four N application rates (0, 5.6, 11.2, and 16.9 kg N ha−1 above base recommendation). All treatments combinations were applied during the early flowering stage of growth (8–10 wk after transplanting), when plants were approximately 120 cm tall. Programs absent of leaf removal generally produced the highest cured leaf yield. The addition of 16.9 kg N ha−1 increased yield when compared to lower N application rates within the 4‐leaf removal program. Nitrogen application did not affect yield in the 8‐leaf removal program. Cured leaf value was greatest in the 0‐leaf removal program (USD $10,131 ha−1) and was reduced in the 4‐ and 8‐leaf programs by $1611 and $2645 ha−1, respectively. Lower‐stalk positions were nearly eliminated in the 8‐leaf removal program, while the 4‐leaf removal program reduced their presence by more than 50%. Ultimately, if these programs are to be encouraged or required by industry, the removal of four leaves per plant proved to be more practical when paired with additional N, due to moderate yield reduction and lower‐stalk leaf production.
The Suitability of the Emerging Double Maize System Towards Sustainable Water Use under a Warm Temperature Continental Monsoon Climate
Authors: Wang Xingya , Liu Xiwei , Wu Qingzhao , Wang Pu , Meng Qingfeng
Published: May 2019

Core Ideas

The yield of double maize system was comparable to the conventional winter wheat–summer maize system.

Double maize system could improve crop production and save water under a warming climate.

Short season–short season with plastic mulching can be applied to 67% of total area in the North China Plain with a yield potential of 20.2 Mg ha−1.

Double cropped winter wheat and summer maize system is a system that can improve food security, however, overexploitation of groundwater for irrigation limits its use. An alternative to the wheat/maize system is double cropped maize system. The objective of this study was to evaluate whether a new double maize system could improve yield with a sustainable water use manner. Higher temperature has provided an opportunity to develop an alternative double maize system across the North China Plain (NCP) using the Hybrid‐Maize model. Six combinations of long‐season and short‐season (LS and SS, respectively) maize varieties and two plastic film mulching treatments were used to evaluate the regional suitability of the new system. The average yield potential of the double maize system ranged from 19.6 to 21.3 Mg ha−1, comparable to the conventional winter wheat–summer maize system (Con W/M). The combination of SS and SS varieties using plastic film mulching (SS–SS[P]) has applicability to the environments with growing degree‐days (GDD) at ∼2566°C worldwide with a yield potential of 20.2 Mg ha−1. Although the similar yield potential can also be achieved for the combinations of SS–LS (P) and LS–SS (P), the frost risk of the two combinations for the second season maize was more than 80%. These results indicated that changing from a Con W/M to the newly‐developed double cropped maize system could result in major improvements in both crop production and water usage under current and future climate scenarios.
Complexity of the aetiology of the suckling piglets diarrhoea
Authors: PEJSAK ZYGMUNT , TRUSZCZYŃSKI MARIAN , TARASIUK1 KAZIMIERZ
Published: May 2019

This review of the literature is characterising the aetiology of the diarrhoea of suckling piglets with reference to pathogenic bacteria and viruses,also including the influence of the unfavourable environmental factors. The laboratory investigations of faecal samples demonstrated the etiological importance of E.coli, not only those with haemolytic properties but also non haemolytic strains. The majority of E.coli strains of etiological importance belonged to pathotype EPEC. These strains produced one or several enterotoxins, being thermostable or termolable.They produce fimbrial antigens: F4, F5, F6 and F41. Strains of Clostridium perfringens cultured from the majority of feaces samples belong to type A. The Rotavirus type A, in comparison with TGEV and PEDV plaid the leading role in the multifactorial aetiology of suckling piglet diarrhoea. Concluding, exact definition of aetiology of piglet diarrhoea is at present not possible and requires further research. These results could eventually more precisely define, than it is possible at present, the passive prophylaxis of the diarrhoea of suckling piglets and a more adequate choice of drugs.
Categorization of animal by-products and labelling of derived products with of glycerol triheptanoate (GTH)
Authors: GRELIK ALEKSANDRA , KOWALCZYK EWELINA , KWIATEK KRZYSZTOF
Published: May 2019

Animal by-products result mainly from the slaughter of animals for human consumption, the production of products of animal origin (such as dairy products), the disposal of dead animals, and disease-control measures. Regardless of their source, they pose a potential risk to public and animal health and the environment. This risk needs to be adequately controlled, either by safe disposal of such products, or by their utilization, provided that strict conditions are maintained to minimize the health risks involved. Animal by-products are classified into categories that reflect the level of risk to public and animal health arising from those by-products (Cat. 1, 2 and 3). According to Commission Regulation (EU) No 142/2011, in processing plants for the processing of Category 1 or 2 material, derived products shall be permanently marked with glycerol triheptanoate (GTH). The minimum content of marker in target materials is 250 mg/kg of fat. For the determination of glycerol triheptanoate in dry meat, bone meals, rendered fat and soil adjuvants, gas chromatography technique and mass spectrometry detection are used
Bluetongue in Europe – the risk of animal import from restricted zones
Authors: ORŁOWSKA ANNA , SMRECZAK MARCIN , ROLA JERZY
Published: May 2019

Bluetongue (BT) is a vector-borne viral disease effecting ruminants caused by bluetongue virus (BTV), transmitted mainly by bites from midges of the genus Culicoides. Since the end of 20th century, BTV is endemic in several European countries and the disease is caused mainly by BTV-8 and BTV-4 infections. Bluetongue virus is characterized by high genetic diversity. To date, over 29 BTV serotypes have been documented, including recently discovered atypical serotypes BTV (25–27). The disease has a high economic impact as it causes economic losses due to animal mortality, reduced productivity and restrictions on the movement of animals. Several reports and numerous observations indicate the contribution of animal movements to the spread of BTV infections. Thus, bluetongue surveillance that includes testing of sentinel animals as well as virological testing of animals susceptible to BTV infection imported from restricted zones due to the presence of BTV is a key factor in maintaining a BT-free status