bluuebunny/crossref_metadata_2025 huggingface dataset:
Contingent intramuscular boosting of P2XR7 axis improves motor function in transgenic ALS mice
Authors: Fabbrizio Paola , D’Agostino Jessica , Margotta Cassandra , Mella Giulia , Panini Nicolò , Pasetto Laura , Sammali Eliana , Raggi Flavia , Sorarù Gianni , Bonetto Valentina , Bendotti Caterina , Nardo Giovanni
Published: December 2021

Amyotrophic lateral sclerosis is a fatal neurodegenerative disorder that leads to progressive degeneration of motor neurons and severe muscle atrophy without effective treatment. Most research on the disease has been focused on studying motor neurons and supporting cells of the central nervous system. Strikingly, the recent observations have suggested that morpho-functional alterations in skeletal muscle precede motor neuron degeneration, bolstering the interest in studying muscle tissue as a potential target for the delivery of therapies. We previously showed that the systemic administration of the P2XR7 agonist, 2′(3′)-O‐(4-benzoylbenzoyl) adenosine 5-triphosphate (BzATP), enhanced the metabolism and promoted the myogenesis of new fibres in the skeletal muscles of SOD1G93A mice. Here we further corroborated this evidence showing that intramuscular administration of BzATP improved the motor performance of ALS mice by enhancing satellite cells and the muscle pro-regenerative activity of infiltrating macrophages. The preservation of the skeletal muscle retrogradely propagated along with the motor unit, suggesting that backward signalling from the muscle could impinge on motor neuron death. In addition to providing the basis for a suitable adjunct multisystem therapeutic approach in ALS, these data point out that the muscle should be at the centre of ALS research as a target tissue to address novel therapies in combination with those oriented to the CNS.
INTERNAL NATURAL TRANSFORMATIONS AND FROBENIUS ALGEBRAS IN THE DRINFELD CENTER
Authors: FUCHS JÜRGEN , SCHWEIGERT CHRISTOPH
Published: December 2021

For ℳ and $$ \mathcal{N} $$
N
finite module categories over a finite tensor category $$ \mathcal{C} $$
C
, the category $$ \mathrm{\mathcal{R}}{ex}_{\mathcal{C}} $$
ℛ

ex
C

(ℳ, $$ \mathcal{N} $$
N
) of right exact module functors is a finite module category over the Drinfeld center $$ \mathcal{Z} $$
Z
($$ \mathcal{C} $$
C
). We study the internal Homs of this module category, which we call internal natural transformations. With the help of certain integration functors that map $$ \mathcal{C} $$
C
-$$ \mathcal{C} $$
C
-bimodule functors to objects of $$ \mathcal{Z} $$
Z
($$ \mathcal{C} $$
C
), we express them as ends over internal Homs and define horizontal and vertical compositions. We show that if ℳ and $$ \mathcal{N} $$
N
are exact $$ \mathcal{C} $$
C
-modules and $$ \mathcal{C} $$
C
is pivotal, then the $$ \mathcal{Z} $$
Z
($$ \mathcal{C} $$
C
)-module $$ \mathrm{\mathcal{R}}{ex}_{\mathcal{C}} $$
ℛ

ex
C

(ℳ, $$ \mathcal{N} $$
N
) is exact. We compute its relative Serre functor and show that if ℳ and $$ \mathcal{N} $$
N
are even pivotal module categories, then $$ \mathrm{\mathcal{R}}{ex}_{\mathcal{C}} $$
ℛ

ex
C

(ℳ, $$ \mathcal{N} $$
N
) is pivotal as well. Its internal Ends are then a rich source for Frobenius algebras in $$ \mathcal{Z} $$
Z
($$ \mathcal{C} $$
C
).
Ultrasound-guided bilateral erector spinae plane block in laparoscopic colon cancer surgery
Authors: Li Qijin , Li Quanchu , Peng Weiping , Liu Zhenzhen , Mai Yaohai , Shi Congying , Mo Ping
Published: December 2021

Background

The efficacy of erector spinae plane block (ESPB) for pain control in other surgeries remains an interesting topic of discussion. This study aimed to evaluate the safety and efficacy and quality of recovery of ultrasound-guided bilateral ESPB in laparoscopic surgery for colon cancer.

Material and methods

In this study 50 patients were included and randomly divided into the intervention group (E group, n = 25) and the control group (C group, n = 25). Patients in the E group received general anesthesia with preoperative bilateral ultrasound-guided ESPB, whereas patients in the C group received general anesthesia with saline injection in the erector spinae plane preoperatively. Data on intraoperative and postoperative anesthetic effects and the effect on enhanced recovery after surgery were recorded and analyzed.

Results

Rocuronium consumption in the intervention group was 82.80 ± 21.70 mg, which was lower than that in the control group (P < 0.05). Visual analog scale scores at 2, 6, and 24 h after surgery in the intervention group were lower than those in the control group (Fbetween = 34.034, P = 0.000). The time to ambulation, consumption of ketorolac tromethamine, time to oral intake and hospital stay after operation in the intervention group were significantly lower than those in the control group (P < 0.05). The block area at the different baselines was significant (Fbetween = 3.211, P = 0.009). The association between baseline and time was significant (Fbaseline * time = 3.268, P = 0.001).

Conclusion

This study confirmed that ultrasound-guided ESPB technology is safe and beneficial for patients with colon cancer undergoing laparoscopic colon surgery.
Effects of leachates from UV-weathered microplastic on the microalgae Scenedesmus vacuolatus
Authors: Rummel Christoph D. , Schäfer Hannah , Jahnke Annika , Arp Hans Peter H. , Schmitt-Jansen Mechthild
Published: December 2021

Plastics undergo successive fragmentation and chemical leaching steps in the environment due to weathering processes such as photo-oxidation. Here, we report the effects of leachates from UV-irradiated microplastics towards the chlorophyte Scenedesmus vacuolatus. The microplastics tested were derived from an additive-containing electronic waste (EW) and a computer keyboard (KB) as well as commercial virgin polymers with low additive content, including polyethylene (PE), polyethylene terephthalate (PET), polypropylene (PP), and polystyrene (PS). Whereas leachates from additive-containing EW and KB induced severe effects, the leachates from virgin PET, PP, and PS did not show substantial adverse effects in our autotrophic test system. Leachates from PE reduced algae biomass, cell growth, and photosynthetic activity. Experimental data were consistent with predicted effect concentrations based on the ionization-corrected liposome/water distribution ratios (Dlip/w) of polymer degradation products of PE (mono- and dicarboxylic acids), indicating that leachates from weathering PE were mainly baseline toxic. This study provides insight into algae toxicity elicited by leachates from UV-weathered microplastics of different origin, complementing the current particle- vs. chemical-focused research towards the toxicity of plastics and their leachates.

Graphical abstract
The role of artificial intelligence in paediatric cardiovascular magnetic resonance imaging
Authors: Taylor Andrew M.
Published: December 2021

Artificial intelligence (AI) offers the potential to change many aspects of paediatric cardiac imaging. At present, there are only a few clinically validated examples of AI applications in this field. This review focuses on the use of AI in paediatric cardiovascular MRI, using examples from paediatric cardiovascular MRI, adult cardiovascular MRI and other radiologic experience.
Complications and Disasters After Minimally Invasive Tissue Augmentation with Different Types of Fillers: A Retrospective Analysis
Authors: Bingoel Alperen S. , Dastagir Khaled , Neubert Lavinia , Obed Doha , Hofmann Thurid R. , Krezdorn Nicco , Könneker Sören , Vogt Peter M. , Mett Tobias R.
Published: December 2021

Background

The interest in youthful appearance and rejuvenating procedures is unbroken in our society. Besides surgical procedures, permanent fillers are utilized. The incorrect and unprofessional use of these substances, auto-injections in particular, have devastating results for patients and are challenging for the plastic surgeon. The aim of this retrospective study was to delineate the differences between permanent and non-permanent filler complications and appropriate treatment options.

Methods

We conducted a retrospective study and researched the hospital information system in the time period from 2001 to 2020. Patients with unprofessional use of permanent fillers, auto-injections and injections of unformulated substances were determined. Age, gender, localization, complications, length of hospital stay, comorbidities, histopathological workups and surgical salvage procedures were noted. Descriptive statistics were calculated.

Results

Seventeen patients were identified from 2001 till 2020. In four cases, auto-injections by the patients were the cause, whereas in the other patients the injections were performed by medical staff. Ages range from 18 to 57 years. Fourteen patients were female and three were male. The injected substances could be recognized as synthol, silicone, vaseline, fat tissue, hyaluronic acid as well as non-medical substances. Surgical procedures were necessary in eleven cases. One patient died because of the underlying diseases.

Conclusion

Our results indicate different sequels of filler materials injected in an unprofessional way, possible complications, conservative and surgical techniques to resolve these rare complications. We suggest a staged therapy adjusted to the clinical symptoms. Milder symptoms can be handled conservatively, whereas severe infections, skin breakdowns or persistent granuloma are justifying indications for surgical treatment.

Level of Evidence V

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.
Optimal lobbying pricing
Authors: Protopappas Konstantinos
Published: December 2021

We study a game with two candidates and two interest groups. The groups offer two kinds of costly contributions to achieve political influence: (a) pre-election campaign contributions to their favourite candidates that increase their probability of winning the election and (b) post-election lobbying contributions to the winning candidate to affect the implemented policy. The candidates are the first to act by strategically choosing the lobbying prices they will charge the groups if they are elected. We characterise the equilibrium values of the lobbying prices set by the candidates as well as the equilibrium levels of the campaign and lobbying contributions chosen by the groups. We show, endogenously, that in the case with symmetric groups and symmetric politicians, a candidate announces to charge the group that supports her in the election a lower lobbying price, justifying this way the preferential treatment to certain groups from the politicians in office. We also consider two extensions (asymmetric groups and politicians who do not commit to the announced prices) and show that the results of the benchmark model hold under specific conditions.
The frequency and time point of outpatient palliative care integration for people before death: an analysis of health insurance data in Lower Saxony, Germany
Authors: Willinger Arvid , Hemmerling Melissa , Stahmeyer Jona Theodor , Schneider Nils , Stiel Stephanie
Published: December 2021

Aim

This study aimed to analyse the number of deceased people who received different types of outpatient palliative care, the length of time prior to death that care was initiated, and their palliative care trajectory including the rate of hospital death.

Subject and methods

Data on 35,514 adults insured by the statutory health insurance who died in 2017 in Lower Saxony, Germany, were analysed. The study examined the provision of three different types of outpatient palliative care: general (GPC), intermediate (IPC) and specialised palliative care (SPC). In addition, oncological palliative care services (OS) were considered. Descriptive analyses include frequencies, timing and duration of these services, the number of inpatient hospital stays and hospital deaths.

Results

Prior to death, 31.4% of the deceased received outpatient palliative care: 21.3% GPC, 6.4% GPC with IPC and/or SPC and/or OS; and 3.7% IPC and/or SPC and/or OS, but no GPC. On average, GPC and OS were initiated 9 months and SPC 3 months prior to death. Six percent of the analytic sample received outpatient palliative care more than 2 years before death. Compared to those without outpatient palliative care, patients who received outpatient palliative care had more and longer inpatient hospital stays, but less frequently died in hospital.

Conclusion

Early outpatient palliative care took place in a minor percentage of deceased. Outpatient palliative care starts late before death for most patients, but enables more people not to die in hospital. However, significantly fewer people receive outpatient palliative care relative to current demand estimates. This is particularly true of general outpatient palliative care.
Knowledge, awareness, attitudes and screening practices towards breast and cervical cancer among women in Nepal: a scoping review
Authors: Rademaker Candice , Bhandary Shital , Harder Helena
Published: December 2021

Aim

Breast and cervical cancers have emerged as major global health challenges and disproportionately affect women in low- and middle-income countries, including Nepal. This scoping review aimed to map the knowledge, attitudes and screening practices for these cancers among Nepali women to improve cancer outcomes and reduce inequality.

Methods

Five electronic databases (CINAHL, Embase, Global Health, PsycINFO and PubMed), grey literature, and reference and citation lists were searched for articles published in English up to June 2021. Articles were screened against inclusion/exclusion criteria, and data from eligible studies were extracted. Results were summarised narratively.

Results

The search yielded 615 articles, 38 of which were included in this scoping review (27 cervical cancer, 10 breast cancer, 1 both cancers). Levels of knowledge regarding breast and cervical varied widely. The main knowledge gaps were misconceptions about symptoms and risk factors, and poor understanding of screening behaviours. Screening practices were mostly inadequate due to socio-cultural, geographical or financial barriers. Positive attitudes towards cervical screening were associated with higher education and increased knowledge of screening modalities. Higher levels of knowledge, (health) literacy and participation in awareness campaigns facilitated breast cancer screening.

Conclusion

Knowledge and screening practices for breast and cervical cancer among Nepali women were poor and highlight the need for awareness and education programmes. Future research should explore community health worker-led awareness and screening interventions for cervical cancer, and programmes to increase the practice of breast self-examination and clinical breast examinations to support early diagnosis of breast cancer.
Magnetic, structural and Mössbauer study of soils from an ancient mining area in Huancavelica-Peru
Authors: Corzo M. A. Castillo , Borja-Castro L. E. , Valladares L. De Los Santos , González J. C. , Medina J. Medina , Quinde A. Trujillo , Barnes C. H. W. , Rodriguez V. A. Peña
Published: December 2021

We present the magnetic, structural and 57Fe Mossbauer characterization of soils collected from an ancient mercury contaminated city named Huancavelica in Peru. The characterization results indicate that silicates and carbonates are the main mineralogical constituents in the samples. In addition, 57Fe Mössbauer spectra at room temperature reveal, the presence of two components: a magnetic component related to magnetic Fe-oxides (magnetite, hematite, goethite) and a high non-magnetic component related to Fe+3 in high spin configuration and tetrahedral coordination in silicates. The magnetization measurements present screening of paramagnetic, ferromagnetic and antiferromagnetic signals, typical from soils containing different silicates and iron minerals. Remarkably the Verwey and Morin transitions corresponding to magnetite and hematite, respectively, are screened by the paramagnetic signal corresponding to the major silicate components in the samples. Overall, the soils are mainly composed of crystalline and amorphous silicates, calcites and iron bearing which are typical from Andean soils.
Online social transparency in enterprise information systems: a risk assessment method
Authors: Alsaedi Tahani , Sherief Nada , Phalp Keith , Ali Raian
Published: December 2021

Teleworking refers to the utilization of information and communication technologies for work done outside the workplace. The Covid-19 crisis led to increased utilisation of social networking tools within enterprises, especially when working remotely. The aim of their use is often to improve situational awareness, coordination, and collaboration amongst employees. Online social transparency, typically done through social networks or enterprise social software, refers to the voluntary sharing of personal and contextual information such as those relating to their own and team status, intentions, motivation, capabilities, goal priorities besides updates on the physical and social context, with other colleagues. An ad-hoc practice of social transparency can introduce risks such as information overload, social loafing and peer pressure. Despite recognising its adverse effects, there is a lack of systematic methods that identify and assess the risks of online social transparency. In this paper, we present a method to identify and evaluate these within enterprises. We present the method’s workflow, stakeholders, the novel artefacts and techniques devised to use and the outcomes to produce. We evaluate our proposed method by applying it in a real organisational context and assess applicability, efficiency, and effectiveness in identifying risks and supporting managers in risk assessment. The results showed that the method gives a framework of thinking and analysis and helps recognize and identify risks in a specialized manner.
Curtailment of Civil Liberties and Subjective Life Satisfaction
Authors: Windsteiger Lisa , Ahlheim Michael , Konrad Kai A.
Published: December 2021

This analysis focuses on the lockdown measures in the context of the Covid-19 crisis in Spring 2020 in Germany. In a randomized survey experiment, respondents were asked to evaluate their current life satisfaction after being provided with varying degrees of information about the lethality of Covid-19. We use reactance as a measure of the intensity of a preference for freedom to explain the variation in the observed subjective life satisfaction loss. Our results suggest that it is not high reactance alone that is associated with large losses of life satisfaction due to the curtailment of liberties. The satisfaction loss occurs in particular in combination with receiving information about the (previously overestimated) lethality of Covid-19.
“Furry tales”: pet ownership’s influence on subjective well-being during Covid-19 times
Authors: Damberg Svenja , Frömbling Lena
Published: December 2021

The social distancing required during Covid-19 times tended to make people feel lonelier than usual. Those with pets might, however, have experienced this less, because pets are known for fostering their owners’ subjective well-being. Building on a recently published structural equation model, our study enhances the understanding of subjective well-being by including the construct social distancing during Covid-19 times. In order to answer our research question—How does human-pet relationship need support influence subjective well-being by considering social isolation during Covid-19 times?—we build on the basic needs theory, assuming that humans as well as their pets have an inherent need of autonomy, relatedness, and competence. Using a multivariate data analysis method, namely partial least squares structural equation modeling (PLS-SEM), we establish a path model and examine the relationship between human-pet relationship need support and subjective well-being by including psychological distress and social isolation during Covid-19 times as mediators. We operationalize subjective well-being as a three-dimensional construct consisting of positive affect, happiness, and life satisfaction. In a sample of 215 pet owners in the USA, supporting their need increases subjective well-being, and decreases the psychological distress and loneliness caused by social isolation during Covid-19 times. Furthermore, psychological distress decreases subjective well-being, whereas perceived loneliness during Covid-19 times does not. Our main contributions are to not only enhance our knowledge on the importance of human-pet relationships in critical times, but also to provide policy makers with insights into what influences people’s subjective well-being, which is closely related to their psychological health.
The future of leadership—How is leadership in small and medium-sized enterprises going to change?
Authors: Ötting Sonja K. , Masjutin Lisa , Maier Günter W.
Published: December 2021

This paper in the Journal Gruppe. Interaktion. Organisation. (GIO) addresses changes in leadership through digitalization and their consequences for leaders. For years, digitalization has been heralding changes such as increasing leadership at a distance or use of digital communication media. Small and medium-sized enterprises (SMEs) now face the task of coping with these changes and have to contend with major uncertainties: What are major determining trends for leaders in SMEs? Which changes will shape leadership and how will they change leadership tasks and success-critical behavior? In semi-structured interviews with seven experts from SMEs we have explored these questions. Trends expected by the experts describe changes in the organizational structures and in work within the company. Structurally, companies will become more agile and diverse, hierarchies will play a less strong role and companies will cooperate more closely with each other. Work will become more location-independent, more influenced by Big Data and many tasks will be made easier or taken over by technology. In relation to established models of leadership tasks and behavior, the experts see a clear shift in tasks in favor of managing human resources, including the development of employees through coaching and the transfer of responsibility. In addition to previous tasks, the experts see managing change as a new task area. This area consists of accompanying change, acting flexibly and agilely, communicating openly and transparently and allowing failure. With regard to changes in success-critical behavior, leaders have to show more strategy orientation, communicate clearly and be open to new ideas and further development.
Traffic Crimes and risky driving: The role of personality and driving anger
Authors: Faílde-Garrido José María , Rodríguez-Castro Yolanda , González-Fernández Antonio , García-Rodríguez Manuel Antonio
Published: December 2021

The current study aims to examine the influence of personality traits (alternative Zuckerman model) and driving anger in the explanation of risky driving style in individuals convicted for road safety offences (N = 245), using as a basis an adaptation of the context-mediated model. This is a transversal, descriptive study designed to be implemented by means of surveys, in which took part 245 men convicted of road safety offences from five prisons in Galicia (a region in northwestern Spain) took part. The average age of the participants was 38.73 years (Sx-9.61), with a range between 18 and 64 years. All participants had three or more years of driving experience. Our data shows that the Impulsive-Sensation Seeking (Imp-SS) personality trait had a direct and positive effect on dangerous driving, while the Activity (Act) trait had a direct but negative effect. The Aggression-Hostility (Agg-Host) trait, in turn, influenced the risky driving style, but not directly, but by raising driving anger levels, so it acted as a powerful mediator between the Aggression-Hostility (Agg-Hos) trait and the risky driving style. In general, our research partially replicates and expands previous findings regarding the model used, the aggression-hostility personality trait (Agg-Host) was placed in the distal context, driving anger in the proximal context, while age and personality traits Activity (Act) and Impulsive-Sensation Seeking (Imp-SS) were direct predictors. The results of this study may have practical implications for the detection and rehabilitation of offenders and penalties for road safety offences.
A Storytelling Robot Managing Persuasive and Ethical Stances via ACT-R: An Exploratory Study
Authors: Augello Agnese , Città Giuseppe , Gentile Manuel , Lieto Antonio
Published: December 2021

We present a storytelling robot, controlled via the ACT-R cognitive architecture, able to adopt different persuasive techniques and ethical stances while conversing about some topics concerning COVID-19. The main contribution of the paper consists in the proposal of a needs-driven model that guides and evaluates, during the dialogue, the use (if any) of persuasive techniques available in the agent procedural memory. The portfolio of persuasive techniques tested in such a model ranges from the use of storytelling to framing techniques and rhetorical-based arguments. To the best of our knowledge, this represents the first attempt of building a persuasive agent able to integrate a mix of explicitly grounded cognitive assumptions about dialogue management, storytelling and persuasive techniques as well as ethical attitudes. The paper presents the results of an exploratory evaluation of the system on 63 participants.
The Role of Executive Function in Children’s Mindfulness Experience
Authors: Butterfield Kaitlyn M. , Roberts Kim P.
Published: December 2021

Objectives

The effects of a 6-week mindfulness program were examined to assess how executive function level played a role in students’ mindful experience. The effects of the mindfulness program were evaluated according to prospective outcomes across students’ level of executive function, in comparison to an active control group.

Methods

Classrooms were randomly assigned to a mindfulness-based program or a health-based active control group. Pre- and early adolescent students in the 5th to 8th grade (N = 52) from two MindfulMe! program classrooms and two HealthyMe! program classrooms (active control group) completed self-reported pre-test and post-test measures to assess mindful attention awareness, strengths and difficulties, anxious arousal, rumination, and optimism. A composite score was created from student-, teacher-, and parent-reported BRIEF2 screening forms to determine students’ approximate level of executive function prior to the beginning of the program.

Results

There was a significant decrease in rumination for students in the mindfulness-based intervention when compared to the active controls. Findings suggest executive function predicted an individual’s change score in total difficulties, mindful attention awareness, optimism, and anxious arousal, after participating in a mindfulness-based intervention.

Conclusions

Mindfulness-based interventions appear to particularly benefit those with higher levels of executive function; however, an active control did not variably impact students according to their level of executive function.
Racialized Sexual Discrimination (RSD) and Psychological Wellbeing among Young Sexual Minority Black Men (YSMBM) Who Seek Intimate Partners Online
Authors: Wade Ryan M. , Bouris Alida M. , Neilands Torsten B. , Harper Gary W.
Published: December 2021

Introduction

Online dating is widespread among young adults, and particularly young sexual minority men. Racialized sexual discrimination (RSD), also known as “sexual racism,” is frequently reported to occur within these digital spaces and may negatively impact the psychological wellbeing of young sexual minority Black men (YSMBM). However, the association between RSD and psychological wellbeing is not well understood.

Methods

Using data (collected between July 2017–January 2018) from a cross-sectional web-survey of YSMBM (N = 603), six multivariable regression models were estimated to examine the association between five RSD subscales and depressive symptoms and feelings of self-worth. RSD subscales were derived from the first preliminarily validated scale of sexual racism.

Results

Analyses revealed that White superiority (β = .10, p < .01), same-race rejection (β = .16, p < .001), and White physical objectification (β = .14, p < .01) were all significantly associated with higher depressive symptoms, and White physical objectification (β = -.11, p < .01) was significantly associated with lower feelings of self-worth.

Conclusions

This study is among the first to examine the relationship between multiple, distinct manifestations of RSD and depressive symptoms and self-worth using quantitative analyses and provides evidence that RSD is negatively associated with psychological wellbeing.

Policy Implications

Site administrators should institute robust anti-racism policies on their platforms and hold users accountable for discriminatory behavior. Activists may also consider forming coalitions and/or developing campaigns to bring about greater awareness of RSD, in an effort to influence site administrators to enact policy change.
Investigation of geophysical challenges in land seismic data acquisition in Nigeria: case study of parts of the Niger Delta region
Authors: Onwubuariri C. N. , Al-Naimi L. S. , Ijeh B. I. , Mgbeojedo T. I. , Igboekwe M. U. , Nnanna L. A.
Published: December 2021

Geophysical analysis was carried out to evaluate the challenges encountered in land seismic exploration within the study area. This analysis cuts across various stages in land seismic acquisition. These stages include the following: the availability of the prospect map as originally planned by the prospect owners—the client, the desk study and planning of this map by the seismology section (planning seismologist) for acquisition convenience and the field implementation of the acquisition which the survey, drill and recording (preloading, shooting, swath move, line check, LAUX crew and recording platform) sections carried out. The challenges observed included environmental challenges, noise interference, weather conditions (statics or electrostatics interference), line break, faulty equipment, wrong detailing, cake or expired explosives, poor or compromised supervision, security and permit challenges. These challenges are peculiar to Nigeria due to inadequate implementation of policies that guide human settlements and activities. Nigeria is within the climate region where most at times it is very impossible to control natural events like cloudy weather, rainfall, thundering and lightening. As such, the problem of static charges interfering with acquired seismic data becomes inevitable, mostly during the rainy season. Almost total dependency on imported technology and lack of readily available experienced manpower also contribute to these challenges, most especially when it has to do with proper inspection of equipment and materials required for the acquisition and supervision processes. Approaches to follow to minimize the observed challenges were equally highlighted.
Improving hydraulic fracturing effectiveness in depleted and low-pressure reservoirs using N2-energized fluids
Authors: Elgibaly A. A. , Salem A. M. , Soliman Y. A.
Published: December 2021

Foamed and energized fluids fracturing has been used in both conventional and unconventional reservoirs, as they reduce the amount of water used and hence minimize deleterious impact on water-sensitive formations. They also aid in the flow back after treatment in reservoirs where drawdown is limited. In this paper, the most important foam properties are presented, in addition, when to use energized fluids fracturing and how to choose the best energizing component with the best quality. The impact of N2-energized fluids fracturing (NEF) on wells that were previously fractured using conventional fracturing fluids is also presented. In addition, a comparison between the results of N2-energized fluids fractured and conventional fluid fractured wells is presented. The effect of using 20 to 50% (NEF) on production through surface well testing and live production data showed excellent and sustainable production rates. An economical study is presented through comparing the total capital cost of both NEF and conventional fluids fracturing, in addition to the hydrocarbon recovery of wells after both types. Data considered in this work represent about 40 wells fractured using NEF in the Egyptian Western Desert.
Numerical modeling and experimental investigation on the effect of low-salinity water flooding for enhanced oil recovery in carbonate reservoirs
Authors: Hosseini Erfan , Sarmadivaleh Mohammad , Mohammadnazar Dana
Published: December 2021

Numerous studies concluded that water injection with modified ionic content/salinity in sandstones would enhance the oil recovery factor due to some mechanisms. However, the effects of smart water on carbonated formations are still indeterminate due to a lack of experimental investigations and researches. This study investigates the effects of low-salinity (Low Sal) solutions and its ionic content on interfacial tension (IFT) reduction in one of the southwestern Iranian carbonated reservoirs. A set of organized tests are designed and performed to find each ion’s effects and total dissolved solids (TDS) on the candidate carbonated reservoir. A sequence of wettability and IFT (at reservoir temperature) tests are performed to observe the effects of controlling ions (sulfate, magnesium, calcium, and sodium) and different salinities on the main mechanisms (i.e., wettability alteration and IFT reduction). All IFT tests are performed at reservoir temperature (198 °F) to minimize the difference between reservoir and laboratory-observed alterations. In this paper, the effects of four different ions (SO42-, Ca2+, Mg2+, Na+) and total salinity TDS (40,000, 20,000, 5000 ppm) are investigated. From all obtained results, the best two conditions are applied in core flooding tests to obtain the relative permeability alterations using unsteady-state methods and Cydarex software. The final part is the simulation of the whole process using the Schlumberger Eclipse black oil simulator (E100, Ver. 2010) on the candidate reservoir sector. To conclude, at Low Sal (i.e., 5000 ppm), the sulfate ion increases sulfate concentration lower IFT, while in higher salinities, increasing sulfate ion increases IFT. Also, increasing calcium concentration at high TDS (i.e., 40,000 ppm) decreases the amount of wettability alteration. In comparison, in lower TDS values (20,000 and 5000 ppm), calcium shows a positive effect, and its concentration enhanced the alteration process. Using Low Sal solutions at water cut equal or below 10% lowers recovery rate during simulations while lowering the ultimate recovery of less than 5%.
Waterflood optimization using an injector producer pair recovery factor, a novel approach
Authors: Alizadeh Nasser , Salek Ben
Published: December 2021

This paper presents an approach to optimize the recovery factor and sweep efficiency in a waterflooding process by automating the optimum injection rate calculations for water injectors using streamline simulation. A streamline simulator is an appropriate tool for modern waterflood management and can be used to determine the dynamic interaction between injector and producer pairs, which will vary over time based on sweep efficiency and operational changes. A streamline simulator can be used to identify injectors, which are not supporting production and contributing mainly to water producing wells. Streamlines illustrate natural fluid-flow paths in the reservoir, which are based on fluid properties, rock properties, well distribution and well rates across the reservoir. A bundle of connected streamlines can provide the oil in place between an injector/producer pair at any given time during a simulation run. Thus, the well pair recovery factors for each injector/producer pair, the produced water cut and the weighting factor for each injector are determined. Multiplying this weighting factor by the injection rates determines the new injection rate for each injector. For a well pair water cut that is lower than the average field water cut, the injection rate will be increased and vice versa. Given a finite volume of injection water, there will be a re-allocating of water from a well pair with a low recovery factor and high water cut and redistributing the water to injectors supporting low water cut producers, thus maximizing the recovery factor and reducing the field water production. The described approach is an automated procedure during the reservoir simulation run, making it appropriate for full field waterflood optimization with many injectors and producers in high-resolution heterogeneous brown reservoirs. This approach can reduce the water cut and increase the recovery factor and extend the life of the waterflooded oil fields. It was initially tested with a synthetic model and later with an actual reservoir model, which will be described in this paper.
Dynamic effects of fault modeling on stair-step and corner-point grids
Authors: Alpak Faruk O. , Chen Tianhong
Published: December 2021

Fault modeling has become an integral element of reservoir simulation for structurally complex reservoirs. Modeling of faults in general has major implications for the simulation grid. In turn, the grid quality control is very important in order to attain accurate simulation results. We investigate the dynamic effects of using stair-step grid (SSG) and corner-point grid (CPG) approaches for fault modeling from the perspective of dynamic reservoir performance forecasting. We have performed a number of grid convergence and grid-type sensitivity studies for a variety of simple, yet intuitive faulted flow simulation problems with gradually increasing complexity. We have also explored the added value of the multipoint flux approximation (MPFA) method over the conventional two-point flux approximation (TPFA) to increase the accuracy of reservoir simulation results obtained on CPGs. Effects of fault seal modeling on grid-resolution convergence and grid-type sensitivity have also been briefly examined. For simple geometries, both SSG and CPG can be used for fault modeling with similar accuracy in conjunction with the pillar-grid approach. This is evidenced by the fact that simulation results from SSG and CPG converge to identical solutions. SSG and CPG yield different results for more complex geometries. Simulation results approach to a converged solution for relatively fine SSGs. However, a SSG only provides an approximation to the fault geometry and reservoir volumes when the grid is coarse. On the other hand, non-orthogonality errors are increasingly evident in relatively more complex faulted models on CPGs and such errors cannot be addressed by grid refinement. It has been observed that MPFA partially addresses the discretization errors on non-orthogonal grids but only from the total flux accuracy perspective. However, transport related errors are still evident. Grid convergence behaviors and grid effects are quite similar with or without fault seal modeling (i.e., dedicated fault-zone modeling by use of scaled-up seal factors) for simple geometries. However, in more complex test cases, we have observed that it is more difficult to achieve converged results in conjunction with fault seal modeling due to increased heterogeneity of the underlying problem.
Simulation of two-phase flow by injecting water and surfactant into porous media containing oil and investigation of trapped oil areas
Authors: Sajadi Seyed Mousa , Jamshidi Saeid , Kamalipoor Meisam
Published: December 2021

Nowadays, as the oil reservoirs reaching their half-life, using enhanced oil recovery methods is more necessary and more common. Simulations are the synthetic process of real systems. In this study, simulation of water and surfactant injection into a porous media containing oil (two-phase) was performed using the computational fluid dynamics method on the image of a real micro-model. Also, the selected anionic surfactant is sodium dodecyl sulfate, which is more effective in sand reservoirs. The effect of using surfactant depends on its concentration. This dependence on concentration in using injection compounds is referred to as critical micelle concentration (CMC). In this study, an injection concentration (inlet boundary) of 1000 ppm was considered as a concentration less than the CMC point (2365 ppm). This range of surfactant concentrations after 4.5 ms increased the porous media recovery factor by 2.21%. Surfactant injection results showed the wettability alteration and IFT finally increases the recovery factor in comparison with water injection. Also, in wide channels, saturation front, and narrow channels, the concentration front has a great effect on the main flowing.
The effect of chemically enhanced oil recovery on thin oil rim reservoirs
Authors: Olabode O. A. , Ogbebor V. O. , Onyeka E. O. , Felix B. C.
Published: December 2021

Oil rim reservoirs are characterised with a small thickness relative to their overlying gas caps and underlying aquifers and the development these reservoirs are planned very carefully in order to avoid gas and water coning and maximise oil production. Studies have shown low oil recoveries from water and gas injection, and while foam and water alternating gas injections resulted in positive recoveries, it is viewed that an option of an application of chemical enhanced oil recovery option would be preferable. This paper focuses on the application of chemical enhanced oil recovery to improve production from an oil rim reservoir in Niger Delta. Using Eclipse black oil simulator, the effects of surfactant concentration and injection time and surfactant alternating gas are studied on overall oil recovery. Surfactant injections at start and middle of production resulted in a 3.7 MMstb and 3.6 MMstb at surfactant concentration of 1% vol, respectively. This amounted to a 6.6% and 6.5% increment over the base case of no injection. A case study of surfactant alternating gas at the middle of production gave an oil recovery estimate of 10.7%.
Dynamics of hydrocarbon production in long-developed fields of the South Caspian basin with emphasis on reserves renewability
Authors: Feyzullayev A. A. , Lerche I. , Mamedova I. M. , Gojayev A. G.
Published: December 2021

The scientific basis of the paper is the concept of renewability of oil and gas resources. In accordance with this concept, the purpose of this paper is to estimate the volumetric rate of natural replenishment of the reservoir with oil and gas using the example of long-developed Bibieybat oil and Garadag gas condensate fields in the South Caspian Basin (SCB). The methodological approach of this assessment is based on the authors' assumption that at the late stage of field development, the recoverable amount of hydrocarbon fluids is compensated by the amount of their natural inflow, as a result of which oil or gas production stabilizes. The analysis of the dynamics of hydrocarbon production for the Bibieybat oil field covered the period from 1935 to 2018, and for the Garadag gas condensate field from 1955 to 1979. The rate of natural oil replenishment calculated for 29 operating facilities of the Bibieybat field varies per well within 0.32–1.4 ton/day (averaging 0.76 ton/day) or about 277 ton/year. The rate of natural gas inflow at the Garadag gas condensate field is about 5.2 thousand m3/day per well.
Implementation of a novel eccentric dog leg reamer in oil well drilling
Authors: Shokry Amir , Elgibaly Ahmed , Salem Adel
Published: December 2021

A high-quality wellbore is generally considered to have a gauge hole, a smooth wellbore and a wellbore with minimum tortuosity. Therefore, dog leg reamers (DLRs) have been recently proposed and implemented to specifically provide a high-quality wellbore which in turn improves the overall drilling performance. These improvements include smoothening the wellbore from high in place dogleg, lowering drag values, improving the tripping performance, increasing the success ratio of wireline logging tools to reach total depths and enhancing the casing and cement jobs. DLRs are an eccentric string reamers which have been recently designed and optimized using modelling software, and a mathematical model has been deduced to specify the weight and torque distribution between the bit and DLR based on mechanical specific energies at bit and DLR with a model accuracy closely matches the field data. A total of twenty five runs all over the world have been performed to date in hole sizes ranging from 12¼″ to 6″. Directional work has also been performed showing good directional control with this system, and no vibration issues have been reported. The development of this down hole tool has added new capability to the industry in the optimization of hole enlargement applications. The benefit is realized in a reduced number of days required to drill the well and in reduced total well cost. In addition, getting casing into the hole sooner reduces the accompanying risks and can contribute to reducing operational nonproductive time. Several case studies from three fields X, Y and Z from Egypt, Oman and Saudi Arabia, respectively, will be discussed to demonstrate the positive economic impact of deploying DLR in not only the deviated holes but also in vertical wells.
Borehole enlargement rate as a measure of borehole instability in hydrate reservoir and its relationship with drilling mud density
Authors: Li Qingchao , Liu Lingling , Yu Baohai , Guo Linian , Shi Sheng , Miao Linchun
Published: December 2021

Borehole collapse will pose a threat to the safety of equipment and personnel during drilling operation. In this paper, a finite element multi-field coupling model for investigating borehole collapse in hydrate reservoir was developed. In this model, fluid seepage, heat transfer, hydrate dissociation and borehole deformation are all considered. Based on which, effects of drilling fluid density on both of hydrate dissociation and borehole collapse are investigated. The investigation results show that disturbance of drilling fluid invasion to hydrate reservoir will lead to hydrate dissociation around wellbore, and dissociation range narrows obviously with the increase in drilling fluid density. When the relative fluid density is 0.98, natural gas hydrates in reservoir with a width of about 16.65 cm around wellbore dissociate completely. However, dissociation range of natural gas hydrate has decreased to 12.08 cm when the relative fluid density is 1.10. Moreover, hydrate dissociation around wellbore caused by drilling fluid invasion may lead to borehole collapse, and borehole collapse can be significantly restrained with the increase in relative fluid density. Borehole enlargement rate is 33.67% when the relative fluid density is 0.98, but nearly no collapse area displays around wellbore when the relative fluid density increases to 1.12. In addition, investigation herein can provide an idea for designing drilling fluid density in hydrate reservoir when different allowable borehole enlargement rate is considered. The minimum fluid density designed for avoiding disastrous borehole collapse increases nonlinearly when higher requirements for borehole stability are proposed.