bluuebunny/crossref_metadata_2025 huggingface dataset:
Multi-model assessment of the late-winter stratospheric response to El Niño and La Niña
Authors: Mezzina Bianca , Palmeiro Froila M. , García-Serrano Javier , Bladé Ileana , Batté Lauriane , Benassi Marianna
Published: June 2021

The impact of El Niño-Southern Oscillation (ENSO) on the late-winter extra-tropical stratosphere (January–March) is assessed in a multi-model framework. Three state-of-the-art atmospheric models are run with prescribed SST anomalies representative of a strong ENSO event, with symmetric patterns for El Niño and La Niña. The well-known temperature perturbation in the lower stratosphere during El Niño is captured by two models, in which the anomalous warming at polar latitudes is accompanied by a positive geopotential height anomaly that extends over the polar cap. In the third model, which shows a lack of temperature anomalies over the pole, the anomalous anticyclone is confined over Canada and does not expand to the polar cap. This anomalous center of action emerges from the large-scale tropospheric Rossby wave train forced by ENSO, and shrinking/stretching around the polar vortex is invoked to link it to the temperature response. No disagreement across models is found in the lower stratosphere for La Niña, whose teleconnection is opposite in sign but weaker. In the middle-upper stratosphere (above 50 hPa) the geopotential height anomalies project on a wavenumber-1 (WN1) pattern for both El Niño and, more weakly, La Niña, and show a westward tilt with height up to the stratopause. It is suggested that this WN1 pattern arises from the high-latitude lower-stratospheric anomalies, and that the ENSO teleconnection to the polar stratosphere can be interpreted in terms of upward propagation of the stationary Rossby wave train and quasi-geostrophic balance, instead of wave breaking.
Do hip-abduction braces work?—A biomechanical evaluation of a commercially available hip brace
Authors: Michalik Roman , Essing Katrin , Rohof Ben , Gatz Matthias , Migliorini Filippo , Betsch Marcel
Published: June 2021

Introduction

Dislocations of the hip joint are a common and clinically relevant complication following total hip arthroplasty (THA). Hip-abduction braces are currently used following operative or non-operative treatment of THA dislocations to prevent re-dislocations. However, the clinical and biomechanical effectiveness of such braces is still controversial.

Material and methods

A total of 30 volunteers were measured during standing and during sitting up and down from a chair task wearing a hip brace set at 70°, 90° or no hip flexion limitation. Range of motion of the hip joint was measured in all directions by an inertial sensor system. Further it has been evaluated if the range of motion would be reduced by the additional use of an arthrodesis cushion.

Results

The use of a hip brace set up with flexion limitation did reduce hip ROM in all directions significantly compared to unhinged brace (p < 0.001–0.035). Performing the “sit down and stand-up task” the brace set up at 70° flexion limitation did reduce maximum hip flexion significantly (p = 0.008). However, in most cases the measured hip flexion angles were greater than the settings of the hip brace should have allowed. The additional use of a cushion can further limit hip motion while sitting up and down from a chair.

Conclusion

This study has demonstrated that hip-abduction braces reduce hip range of motion. However, we also found that to achieve a flexion limitation of the hip to 90°, the hip brace should be set at a 70° hip flexion limitation.
atoh8 expression pattern in early zebrafish embryonic development
Authors: Fragale Ninfa , Divvela Satya Srirama Karthik , Brand-Saberi Beate
Published: June 2021

Atonal homologue 8 (atoh8) is a basic helix-loop-helix transcription factor expressed in a variety of embryonic tissues. While several studies have implicatedatoh8in various developmental pathways in other species, its role in zebrafish development remains uncertain. So far, no studies have dealt with an in-depth in situ analysis of the tissue distribution ofatoh8in embryonic zebrafish. We set out to pinpoint the exact location ofatoh8expression in a detailed spatio-temporal analysis in zebrafish during the first 24 h of development (hpf). To our surprise, we observed transcription from pre-segmentation stages in the paraxial mesoderm and during the segmentation stages in the somitic sclerotome and not—as previously reported—in the myotome. With progressing maturation of the somites, the restriction ofatoh8to the sclerotomal compartment became evident. Double in situ hybridisation withatoh8andmyoDrevealed that both genes are expressed in the somites at coinciding developmental stages; however, their domains do not spatially overlap. A second domain ofatoh8expression emerged in the embryonic brain in the developing cerebellum and hindbrain. Here, we observed a specific expression pattern which was again in contrast to the previously published suggestion ofatoh8transcription in neural crest cells. Our findings point towards a possible role ofatoh8in sclerotome, cerebellum and hindbrain development. More importantly, the results of this expression analysis provide new insights into early sclerotome development in zebrafish—a field of research in developmental biology which has not received much attention so far.
An egocentric straight-ahead bias in primate’s vision
Authors: Cottereau Benoit R. , Trotter Yves , Durand Jean-Baptiste
Published: June 2021

As we plan to reach or manipulate objects, we generally orient our body so as to face them. Other objects occupying the same portion of space will likely represent potential obstacles for the intended action. Thus, either as targets or as obstacles, the objects located straight in front of us are often endowed with a special behavioral status. Here, we review a set of recent electrophysiological, imaging and behavioral studies bringing converging evidence that the objects which lie straight-ahead are subject to privileged visual processing. More precisely, these works collectively demonstrate that when gaze steers central vision away from the straight-ahead direction, the latter is still prioritized in peripheral vision. Straight-ahead objects evoke (1) stronger neuronal responses in macaque peripheral V1 neurons, (2) stronger EEG and fMRI activations across the human visual cortex and (3) faster reactive hand and eye movements. Here, we discuss the functional implications and underlying mechanisms behind this phenomenon. Notably, we propose that it can be considered as a new type of visuospatial attentional mechanism, distinct from the previously documented classes of endogenous and exogenous attention.
Correction to: Model reduction in computational homogenization for transient heat conduction
Authors: Waseem A. , Heuzé T. , Stainier L. , Geers M. G. D. , Kouznetsova V. G.
Published: June 2021

A Correction to this paper has been published: https://doi.org/10.1007/s00466-019-01767-3
Effectiveness of naloxegol in patients with cancer pain suffering from opioid-induced constipation
Authors: Lemaire Antoine , Pointreau Yoann , Narciso Bérengère , Piloquet François-Xavier , Braniste Viorica , Sabaté Jean-Marc
Published: June 2021

Purpose

Naloxegol, an oral once-daily peripherally acting mu-opioid receptor antagonist, is indicated for the treatment of opioid-induced constipation (OIC) with inadequate response to laxative(s), in cancer and non-cancer patients. This study mainly aimed to assess in real-life conditions the efficacy and safety of naloxegol in cancer pain patients and the evolution of their quality of life.

Methods

A non-interventional, 4-week follow-up study was conducted in 24 French oncology and pain centers between 2018 and 2019. Eligible patients were aged ≥ 18 years, treated with opioids for cancer pain, and started naloxegol for OIC with inadequate response to laxatives. The rate of the response to naloxegol (primary criterion) was assessed at W4. The evolution of quality of life was measured using the Patient Assessment of Constipation Quality of Life (PAC-QOL).

Results

A total of 124 patients were included (mean age, 62 ± 12 years; ECOG ≤ 2, 79%; primary cancer, lung 18%, breast 16%, prostate 11%, head and neck 9%, digestive 9%…; metastatic stage, 80%). At inclusion, the median opioid dosage was 60 mg of oral morphine or equivalent. At W4, the response rate was 73.4% (95% CI [63.7–83.2%]), and 62.9% (95% CI [51.5–74.2%]) of patients had a clinically relevant change in quality of life (decrease in PAC-QOL score ≥ 0.5 point). Adverse events related to naloxegol were reported in 8% of patients (7% with gastrointestinal events; one serious diarrhea).

Conclusion

This real-world study shows that naloxegol is effective and well tolerated in cancer pain patients with OIC and that their quality of life improves under treatment.
News media representations of women who kill their newly born children
Authors: Eisenwort B. , Arias P. Fernandez , Klier C. M. , Till B.
Published: June 2021

This paper presents a first quantitative analysis of language in media reports of neonaticide and a comparative examination of language use within the reports. One thousand twenty-seven Austrian print media reports from 2004 to 2014 were retrieved; after exclusion, 331 were analysed using the Linguistic Inquiry and Word Count (LIWC) software. After a preliminary analysis, a comparative analysis was carried out between reports on the Graz case and all other cases. The preliminary analysis revealed that a majority of media reports were related to one repeat neonaticide case (Graz) despite not being clinically different from other cases identified for the same period. The comparative linguistic analysis shows some statistically significant differences relating to the domains of emotional words (less words of anxiety, sadness) and family and in the category of insight and certainty (more words). The unexpected media attention on the Graz case and the ensuing verdict, which was in contradiction with the Austrian infanticide act, might have been influenced by the way language was used by journalists and the media. The authors suggest guidelines on sensitive media reporting are required.
Amygdala reactivity and ventromedial prefrontal cortex coupling in the processing of emotional face stimuli in attention-deficit/hyperactivity disorder
Authors: Viering Tammo , Naaijen Jilly , van Rooij Daan , Thiel Christiane , Philipsen Alexandra , Dietrich Andrea , Franke Barbara , Buitelaar Jan , Hoekstra Pieter J.
Published: June 2021

Impaired emotion recognition is common in individuals with attention-deficit/hyperactivity disorder (ADHD) and may, via deficient emotion self-regulation, relate to the frequently co-occurring affective and social problems. The present study used an emotional face-matching task and functional magnetic resonance imaging (fMRI) to investigate neural responses during the processing of angry and fearful faces and visuo-spatial control stimuli. Additionally, measures for emotion dysregulation, ADHD type, and age were investigated in relation to the behavioral and neural fMRI data. We utilized a sample of 61 adolescents/young adults with ADHD and 51 age-matched healthy controls (age range: 12–28 years). Participants with ADHD had higher emotion dysregulation scores than controls. They also reacted slower and less accurate in response to emotional but not visuo-spatial control stimuli. Neural response differences between emotional and visuo-spatial trials were significantly smaller in cases, particularly in the left amygdala. While coupling between the right amygdala and bilateral ventromedial prefrontal cortex was stronger for emotional than visuo-spatial stimuli in control subjects, levels of positive coupling between the trial types did not significantly differ in participants with ADHD. Neither emotion dysregulation scores, nor ADHD type or age were related to the behavioral and neural processing alterations during the emotional face-matching task. Results indicate that emotion recognition deficits in ADHD are particularly associated with lower amygdala activation to emotional stimuli and alterations in the functional connections of the amygdala to medial prefrontal areas. Emotion recognition deficits and associated neural alterations were unrelated to emotion dysregulation, ADHD type, or age.
The multifunctional role of linear features in traditional silvopastoral systems: the sabana de morro in Dolores (El Salvador) and the pastures with carob trees in Ragusa (Italy)
Authors: Venturi Martina , Piras Francesco , Corrieri Federica , Martinez Aguilar Ever Alexis , Santoro Antonio
Published: June 2021

Traditional agro-silvo-pastoral systems are becoming each day more important, representing multifunctional systems that can contribute to the preservation of agrobiodiversity and of traditional knowledge and associated culture, to the wellbeing of local communities and to sustainable development of rural areas, as testified by the increasing interest regarding the Globally Important Agricultural Heritage Systems (GIAHS) Programme of the Food and Agriculture Organization (FAO). Despite many researches on traditional agro-silvo-pastoral systems tend to focus only on land uses and land use changes, is also important to analyse the different features that characterize cultural landscapes, as well as to produce detailed spatial maps, in order to preserve and valorise these systems as a whole. The paper intends to compare two traditional silvopastoral systems in two different continents and environments: sabana de morro (El Salvador) and pastures with carob trees (Italy), considered as good example of biocultural diversity. Both these sites are characterized by extensive cattle breeding in a hot climate under the shade of trees, whose fruits can also integrate the animal diet. The study analyzed the traditional landscape structure, with particular attention to the presence of linear elements, that act as property divisions and as ecological corridors, contributing to biodiversity at landscape scale. Sabana de Morro is characterized by a complex system of hedges that enhances the variety of species, while an extensive network of dry-stone walls divides the Sicilian pastures with carob trees. These two different types of linear elements created thanks to the local farmers’ knowledge are made of different materials but can play a similar ecological and social function, acting as a division between one pasture and another, as a delimitation of property boundaries, and are necessary to allow a correct pasture management. Despite the differences, these two traditional linear features deeply characterize the landscape structure and fragmentation, creating important microhabitat for many animal and vegetal species and a network of ecological corridors. For these reasons the conservation of linear features should be promoted at planning level, as well as their restoration. Thanks to the applied methodology, it was possible to identify peculiarities and vulnerabilities of linear features and of the systems as a whole, so that it will be possible to create effective management and conservation tools.
Risk factors for early-onset colorectal cancer: a population-based case–control study in Ontario, Canada
Authors: Chang Vicky C. , Cotterchio Michelle , De Prithwish , Tinmouth Jill
Published: June 2021

Purpose

There has been an alarming increase in colorectal cancer (CRC) incidence among young adults aged < 50 years, and factors driving this upward trend are unknown. This study investigated associations between various medical, lifestyle, and dietary factors and risk of early-onset CRC (EO-CRC).

Methods

A population-based case–control study was conducted in Ontario, Canada during 2018–2019. EO-CRC cases aged 20–49 years (n = 175) were identified from the Ontario Cancer Registry; sex- and age group-matched controls (n = 253) were recruited through random digit dialing. Data on potential a priori risk factors were collected using a web-based self-reported questionnaire. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using multivariable logistic regression.

Results

Family history of CRC in a first- or second-degree relative (OR 2.37; 95% CI 1.47–3.84), longer sedentary time (≥ 10 vs. < 5 h/day, OR 1.93; 95% CI 1.02–3.65), greater consumption of sugary drinks (≥ 7 vs. < 1 drinks/week, OR 2.99; 95% CI 1.57–5.68), and a more Westernized dietary pattern (quartile 4 vs. 1, OR 1.92; 95% CI 1.01–3.66) were each associated with an increased risk of EO-CRC. Conversely, calcium supplement use (OR 0.53; 95% CI 0.31–0.92), history of allergy or asthma (OR 0.62; 95% CI 0.39–0.98), and greater parity in females (≥ 3 vs. nulliparity, OR 0.29; 95% CI 0.11–0.76) were each associated with a reduced risk.

Conclusion

Modifiable factors, particularly sedentary behavior and unhealthy diet including sugary drink consumption, may be associated with EO-CRC risk. Our findings, if replicated, may help inform prevention strategies targeted at younger persons.
Assessing the System Vibration of Circular Sawing Machine in Carbonate Rock Sawing Process Using Experimental Study and Machine Learning
Authors: Mikaeil Reza , Mokhtarian Mojtaba , Shaffiee Haghshenas Sina , Careddu Nicola , Alipour Aref
Published: June 2021

Predicting the vibration of the circular sawing machine is very important in examining the performance of the sawing process, as it shows the amount of energy consumption of the circular sawing machine. Also, this factor is directly related to maintenance cost, such that with a small increase in the level of vibration, the maintenance cost increases to a large extent. This paper presents new prediction models to assess the vibration of circular sawing machine. An evaluation model based on the imperialist competitive algorithm as one of the most efficient artificial intelligence techniques was used for estimation of sawability of the dimension stone in carbonate rocks. For this purpose, four main physical and mechanical properties of rock including Schimazek’s F-abrasivity, uniaxial compressive strength, mean Mohs hardness, and Young’s modulus as well as two operational parameters of circular sawing machine including depth of cut and feed rate, were investigated and measured. In the predicted model, the system vibration in stone sawing was considered as a dependent variable. The results showed that the system vibration can be investigated using the newly developed machine learning models. It is very suitable to assess the system vibration based on the mechanical properties of rock and operational properties.
The role of land use and land cover change in climate change vulnerability assessments of biodiversity: a systematic review
Authors: Santos Maria J. , Smith Adam B. , Dekker Stefan C. , Eppinga Maarten B. , Leitão Pedro J. , Moreno-Mateos David , Morueta-Holme Naia , Ruggeri Michael
Published: June 2021

Context

For many organisms, responses to climate change (CC) will be affected by land-use and land-cover changes (LULCC). However, the extent to which LULCC is concurrently considered in climate change vulnerability assessments (CCVAs) is unclear.

Objectives

We identify trends in inclusion of LULCC and CC in vulnerability assessments of species and the direction and magnitude of their combined effect on biodiversity. Further, we examine the effect size of LULCC and CC in driving changes in “currencies” of response to CC, such as distribution, abundance and survival.

Methods

We conducted a systematic literature review of articles published in the last 30 years that focused on CCVA and accounted for impacts of both CC and LULCC.

Results

Across 116 studies, 34% assumed CC and LULCC would act additively, while 66% allowed for interactive effects. The majority of CCVAs reported similar effect sizes for CC and LULCC, although they affected different CCVA currencies. Only 14% of the studies showed larger effects of CC than of LULCC. Another 14% showed larger effects of LULCC than CC, specifically for dispersal, population viability, and reproduction, which tend to be strongly affected by fragmentation and disturbance. Although most studies found that LULCC and CC had negative effects on species currencies, in some cases effects were neutral or even positive.

Conclusions

CCVAs that incorporate LULCC provided a better account of drivers of vulnerability, and highlight aspects of drivers that are generally more amenable to on-the-ground management intervention than CCVAs that focus on CC alone.
Exact Markov chain-based runtime analysis of a discrete particle swarm optimization algorithm on sorting and OneMax
Authors: Mühlenthaler Moritz , Raß Alexander , Schmitt Manuel , Wanka Rolf
Published: June 2021

Meta-heuristics are powerful tools for solving optimization problems whose structural properties are unknown or cannot be exploited algorithmically. We propose such a meta-heuristic for a large class of optimization problems over discrete domains based on the particle swarm optimization (PSO) paradigm. We provide a comprehensive formal analysis of the performance of this algorithm on certain “easy” reference problems in a black-box setting, namely the sorting problem and the problem OneMax. In our analysis we use a Markov model of the proposed algorithm to obtain upper and lower bounds on its expected optimization time. Our bounds are essentially tight with respect to the Markov model. We show that for a suitable choice of algorithm parameters the expected optimization time is comparable to that of known algorithms and, furthermore, for other parameter regimes, the algorithm behaves less greedy and more explorative, which can be desirable in practice in order to escape local optima. Our analysis provides a precise insight on the tradeoff between optimization time and exploration. To obtain our results we introduce the notion of indistinguishability of states of a Markov chain and provide bounds on the solution of a recurrence equation with non-constant coefficients by integration.
Community pharmacists’ perceptions on providing fall prevention services: a mixed-methods study
Authors: Gemmeke Marle , Koster Ellen S. , Rodijk Eline A. , Taxis Katja , Bouvy Marcel L.
Published: June 2021

Background Pharmacists may contribute to fall prevention particularly by identifying and deprescribing fall risk-increasing drugs (FRIDs) in patients with high fall risk. Objective To assess community pharmacists’ perceptions on providing fall prevention services, and to identify their barriers and facilitators in offering these fall prevention services including deprescribing of FRIDs. Setting A mixed-methods study was conducted with Dutch pharmacists. Method Quantitative (ranking statements on a Likert scale, survey) and qualitative data (semi-structured interviews) were collected. Out of 466 pharmacists who were invited to participate, 313 Dutch pharmacists ranked statements, about providing fall prevention, that were presented during a lecture, and 205 completed a survey. To explore pharmacists’ perceptions in-depth, 16 were interviewed. Quantitative data were analysed using descriptive statistics. All interviews were audiotaped and transcribed verbatim. The capability opportunity motivation-behaviour model was applied to interpret and analyse the findings of qualitative data. Main outcome measure Community pharmacists’ views on providing fall prevention. Results Pharmacists stated that they were motivated to provide fall prevention. They believed they were capable of providing fall prevention by FRID deprescribing. They perceived limited opportunities to contribute. Major barriers included insufficient multidisciplinary collaboration, patient unwillingness to deprescribe FRIDs, and lack of time. Facilitators included goal-setting behaviour, financial compensation, and skilled communication. Conclusion Despite the complex decision-making process in medication-related fall prevention, community pharmacists are motivated and feel capable of providing fall prevention. Opportunities for pharmacists to provide fall prevention services should be enhanced, for example by implementing multidisciplinary agreements.
Knowledge of future contingents
Authors: Iacona Andrea
Published: June 2021

This paper addresses the question whether future contingents are knowable, that is, whether one can know that things will go a certain way even though it is possible that things will not go that way. First I will consider a long-established view that implies a negative answer, and draw attention to some endemic problems that affect its credibility. Then I will sketch an alternative line of thought that prompts a positive answer: future contingents are knowable, although our epistemic access of them is limited in some important respects.
Effects of orthography in the picture-word task: Evidence from Japanese scripts
Authors: Dylman Alexandra S. , Kikutani Mariko , Sasaki Miho , Barry Christopher
Published: June 2021

The picture-word task presents participants with a number of pictured objects together with a written distractor word superimposed upon each picture, and their task is to name the depicted object while ignoring the distractor word. Depending on the specific picture and word combination, various effects, including the identity facilitation effect (e.g., DOG + dog) and the semantic interference effect (e.g., GOAT + cow), are often observed. The response patterns of the picture-word task in terms of naming latencies reflect the mechanisms underlying lexical selection in speech production. Research using this method, however, has typically focused on alphabetic languages, or involved bilingual populations, making it difficult to specifically investigate orthographic effects in isolation. In this paper, we report five experiments investigating the role of orthography in the picture-word task by varying distractor script (using the multiscriptal language Japanese, and pseudohomophonic spellings in English) across three different populations (Japanese monolinguals, Japanese-English bilinguals, and English monolinguals), investigating both the identity facilitation effect and the semantic interference effect. The results generally show that the magnitude of facilitation is affected by orthography even within a single language. The findings and specific patterns of results are discussed in relation to current theories on speech production.
The role of source reliability in belief polarisation
Authors: Henderson Leah , Gebharter Alexander
Published: June 2021

Psychological studies show that the beliefs of two agents in a hypothesis can diverge even if both agents receive the same evidence. This phenomenon of belief polarisation is often explained by invoking biased assimilation of evidence, where the agents’ prior views about the hypothesis affect the way they process the evidence. We suggest, using a Bayesian model, that even if such influence is excluded, belief polarisation can still arise by another mechanism. This alternative mechanism involves differential weighting of the evidence arising when agents have different initial views about the reliability of their sources of evidence. We provide a systematic exploration of the conditions for belief polarisation in Bayesian models which incorporate opinions about source reliability, and we discuss some implications of our findings for the psychological literature.
Correction to: Darcy–Brinkman–Forchheimer Model for Film Boiling in Porous Media
Authors: Avramenko A. A. , Shevchuk Igor V. , Kovetskaya M. M. , Kovetska Y. Y.
Published: June 2021

A correction to this paper has been published: https://doi.org/10.1007/s11242-021-01631-0
A self-supervised learning strategy for postoperative brain cavity segmentation simulating resections
Authors: Pérez-García Fernando , Dorent Reuben , Rizzi Michele , Cardinale Francesco , Frazzini Valerio , Navarro Vincent , Essert Caroline , Ollivier Irène , Vercauteren Tom , Sparks Rachel , Duncan John S. , Ourselin Sébastien
Published: June 2021

Purpose

Accurate segmentation of brain resection cavities (RCs) aids in postoperative analysis and determining follow-up treatment. Convolutional neural networks (CNNs) are the state-of-the-art image segmentation technique, but require large annotated datasets for training. Annotation of 3D medical images is time-consuming, requires highly trained raters and may suffer from high inter-rater variability. Self-supervised learning strategies can leverage unlabeled data for training.

Methods

We developed an algorithm to simulate resections from preoperative magnetic resonance images (MRIs). We performed self-supervised training of a 3D CNN for RC segmentation using our simulation method. We curated EPISURG, a dataset comprising 430 postoperative and 268 preoperative MRIs from 430 refractory epilepsy patients who underwent resective neurosurgery. We fine-tuned our model on three small annotated datasets from different institutions and on the annotated images in EPISURG, comprising 20, 33, 19 and 133 subjects.

Results

The model trained on data with simulated resections obtained median (interquartile range) Dice score coefficients (DSCs) of 81.7 (16.4), 82.4 (36.4), 74.9 (24.2) and 80.5 (18.7) for each of the four datasets. After fine-tuning, DSCs were 89.2 (13.3), 84.1 (19.8), 80.2 (20.1) and 85.2 (10.8). For comparison, inter-rater agreement between human annotators from our previous study was 84.0 (9.9).

Conclusion

We present a self-supervised learning strategy for 3D CNNs using simulated RCs to accurately segment real RCs on postoperative MRI. Our method generalizes well to data from different institutions, pathologies and modalities. Source code, segmentation models and the EPISURG dataset are available at https://github.com/fepegar/resseg-ijcars.
Treatment Fidelity in Brief Versus Standard-Length School-Based Interventions for Youth with Anxiety
Authors: Husabo Elisabeth , Haugland Bente S. M. , McLeod Bryce D. , Baste Valborg , Haaland Åshild Tellefsen , Bjaastad Jon Fauskanger , Hoffart Asle , Raknes Solfrid , Fjermestad Krister W. , Rapee Ronald M. , Ogden Terje , Wergeland Gro Janne
Published: June 2021

To examine treatment fidelity in a randomized controlled trial of indicated school-based cognitive-behavioral therapy (CBT) delivered in groups to youth with anxiety. We investigated whether adherence and competence (a) differed across brief and standard-length CBT, and (b) if adherence and competence predicted change in anxiety symptoms and impairment. Method: Sessions were observationally coded with the Competence and Adherence Scale for CBT for Anxiety Disorders in Youth. Coders (N = 7) rated 104 sessions from 52 groups delivered by 32 facilitators (M age = 43.2 years, SD = 8.1) to 295 youth (M age = 14.0 years, SD = 0.8). Outcomes were youth- and parent-reported anxiety symptoms and impairment at post-intervention and 1-year follow-up. Linear mixed effect models were used to analyze whether fidelity predicted clinical outcomes. Results: Levels of adherence and competence were adequate in both programs, but higher in brief compared to standard-length CBT p < .001 and p = .010, respectively). Neither adherence nor competence predicted clinical outcomes at any timepoints. Conclusion: Higher levels of adherence and competence in brief CBT suggest that it may be easier for novice CBT providers to achieve fidelity in simplified and less flexible interventions. Contrary to expectation, adherence and competence did not predict clinical outcomes.
Effect of fiber on the rheological properties of gelled acid
Authors: Gou Bo , Zeng Mingyong , Wang Kunjie , Li Xiao , Guo Jianchun
Published: June 2021

Degradable fiber is widely used to assist gelled acid diversion and reduce acid leak-off in the acid stimulation of carbonate hydrocarbon reservoirs in Sichuan Basin of China. The rheological properties of an acid system will affect the geometry of the acid-etching fracture. However, the effect of fiber on the rheological properties of gelled acid is not yet clear. This paper investigates the rheological properties of gelled acid with various fiber concentrations at different temperatures. The results show that when the temperature is less than the degradable temperature of the fiber, the apparent viscosity of gelled acid rises gradually with an increase in fiber concentration, while the fiber has no significant effect on the viscosity of gelled acid at the degradable temperature. The dissolution process of fiber in gelled acid experiences none-dissolution, surface dissolution, dissolution and fining, and a complete dissolution stage from low to high temperatures, which all have different effects on gelled acid viscosity. The fiber links more gelling agent molecules of gelled acid together to form a quasi-network structure between the fiber and fiber and the fiber and polymer, which results in a rise in the viscosity of gelled acid. The acid system also shows a strong shear thinning property under different temperatures and fiber concentrations. However, the power-law index n of this acid system always maintains a steady average value of about 0.181, while the change pattern of consistency index K is similar to the change in viscosity with varying fiber concentrations and temperatures. The research results are useful for acid fracturing treatment design in carbonate reservoir.
Quantification method of suspended solids in micromodel using image analysis
Authors: Jahari Ahmad Fadhil , Shafian Siti Rohaida Mohd , Husin Hazlina , Razali Norzafirah , Irawan Sonny
Published: June 2021

Micromodel can provide valuable information to improve understanding of pore-scale transport phenomenon and can also be utilized to simulate the transport process at pore scale. This research aims to propose settlement option for quantification of suspended solids in micromodel. The micromodel is used to mimic the formation damage which occurs in reservoir formation that could simultaneously affect enhanced oil recovery. This is done by utilizing visual image interpretation through image analysis on micromodel chip. Following the quantification of suspended solids, the micromodel was injected with brine that eventually forms agglomeration. Images are taken from NIS-Element AR microscope automatically in RGB color profile and then made into grayscale and finally into binary modes. Since the micromodel is simulated in 2D form structure, the quantification method complemented with image analysis is focusing on the quantified area, µm2 region of interest categorized into 3 main groups of area B05, M45 and T50, respectively. This research will explore on segmentation and thresholding processes of the visual data acquired from micromodel experiment. An image-based computational algorithm is programmed in MATLAB Image Processing Toolbox and ImageJ; hence, suspended solids in porous media could be quantified from the visual image executed in micromodel.
Biostratigraphic and petrological characteristics of Cretaceous–Paleogene sediments in the eastern Cuu Long delta
Authors: Dam Mai Hoang , Tuyen Vu Thi , Trieu Nguyen Tan , Tham Nguyen Thi
Published: June 2021

The basic structure of reservoir models is strongly affected by the stratigraphic interpretation and the properties of reservoir rock. The estimation of the volume of hydrocarbon accumulation will depend on the accuracy of predicting and distributing reservoir quality. Biostratigraphic and sedimentary petrologic results provide geological information to clarify the stratigraphy and properties of sedimentary rocks on the eastern margin of the Cuu Long delta plain trough. On the basis of stratigraphic correlation of the wells and studying the structures of the area, the deposition, thickness of sediments and the ability to correlate with prospect rocks on the southeastern Vietnam continental shelf were determined. The results have identified the basement rock of wells TC-1 and TC-2, which are Cretaceous metasandstones and were deposited in freshwater fluvial environments with high-energy conditions. The upper Paleogene sediments were overlaid directly on the Cretaceous basement rock in the TC-2 well but were completely absent in the TC-1 well. The lithologic composition is mainly feldspathic litharenite sandstone, which is formed in freshwater fluvial and freshwater lacustrine environments. This study provides new data on stratigraphic column of the eastern Cuu Long delta plain. The data show that the age of the sedimentary basement rock is Cretaceous which has not been determined in previous studies. The findings of this study can help for better understanding of the geological development history and the completely stratigraphic column of the Cuu Long delta to correlate with objects that are hydrocarbon accumulation in Cuu Long sedimentary basin in order to improve efficiency in petroleum exploration activities.
Shale gas: a step toward sustainable energy future
Authors: Bellani Jayesh , Verma Harsh Kumar , Khatri Dhrumil , Makwana Dhruv , Shah Manan
Published: June 2021

The world energy consumption is going to rise by nearly 50% in 2050 when compared to 2010. With conventional and unconventional reserves depleting, demand for energy supply is rising. The feasibility and the current efficiency of renewable energy sources may not be capable of satisfying the world energy demand by themselves. Increase in production of non-renewable energy source, i.e., the fossil fuels may help to fulfill the energy requirement of future generations. Shale gas is one of the unconventional sources of energy. Shale gas deposits are scattered all over the planet in low-permeability and low porosity reservoirs. India has overall reserves of shale gas between 600 and 2000 TCF, of which 63 TCF is of recoverable shale gas (Pradhan and Prakash 2000). Shale production depends on many factors such as political matters, wars, social and economic aspects, and exploration techniques. Depending on the recoverable reserve (RR), production of shale gas entails different methods and with a different method, comes different problems described and discussed in this manuscript. Along with the problems, the technically recoverable reserves of different countries, different production mechanisms, and economic aspects of shale gas are also discussed.
A comprehensive review of the chemical-based conformance control methods in oil reservoirs
Authors: Sagbana Perekaboere Ivy , Abushaikha Ahmad Sami
Published: June 2021

The production of excess water during oil recovery creates not only a major technical problem but also an environmental and cost impact. This increasing problem has forced oil companies to reconsider methods that promote an increase in oil recovery and a decrease in water production. Many techniques have been applied over the years to reduce water cut, with the application of chemicals being one of them. Chemicals such as polymer gels have been widely and successfully implemented in several oil fields for conformance control. In recent years, the application of foam and emulsions for enhanced oil recovery projects has been investigated and implemented in oil fields, but studies have shown that they can equally act as conformance control agents with very promising results. In this paper, we present a comprehensive review of the application of polymer gel, foam and emulsion for conformance control. Various aspects of these chemical-based conformance control methods such as the mechanisms, properties, applications, experimental and numerical studies and the parameters that affect the successful field application of these methods have been discussed in this paper. Including the recent advances in chemical-based conformance control agents has also been highlighted in this paper.
Quantitative characterization of collapse and fracture pressure uncertainty based on Monte Carlo simulation
Authors: Ya-nan Sheng , Weiting Li , Jinbao Jiang , Kai Lan , Hua Kong , Yupeng Yan
Published: June 2021

The complex geological conditions of drilling, the difficulty of formation collapse and fracture pressure prediction in South Sichuan work area lead to the complex drilling and frequent failure, which seriously restricts the safe and efficient development of shale gas. In view of this problem, this paper has carried out relevant research. First of all, the existing calculation model of formation collapse and fracture pressure is established and improved; on this basis, the sources of uncertainty in the calculation model of collapse and fracture pressure are analyzed, mainly the in-situ stress and rock mechanics parameters, which have a lot of uncertainties; then, the uncertainty of rock mechanics parameters and in-situ stress is analyzed, and its probability is determined. Finally, based on Monte Carlo simulation, the quantitative characterization method of formation collapse and fracture pressure uncertainty is established. The prediction result of collapse and fracture pressure is no longer a single curve or value, but an interval, which is more practical for drilling in complex geological environment. The results of this study are helpful to better describe the collapse and fracture pressure of complex formation and can provide more valuable reference data for drilling design.
Analysis of permeability based on petrophysical logs: comparison between heuristic numerical and analytical methods
Authors: Gholanlo H. Heydari
Published: June 2021

A series of novel heuristic numerical tools were adopted to tackle the setback of permeability estimation in carbonate reservoirs compared to the classical methods. To that end, a comprehensive data set of petrophysical data including core and log in two wells was situated in Marun Oil Field. Both wells, Well#1 and Well#2, were completed in the Bangestan reservoir, having a broad diversity of carbonate facies. In the light of high Lorenz coefficients, 0.762 and 0.75 in Well#1 and Well#2, respectively, an extensive heterogeneity has been expected in reservoir properties, namely permeability. Despite Well#1, Well#2 was used as a blinded well, which had no influence on model learning and just contributed to assess the validation of the proposed model. An HFU model with the aim of discerning the sophistication of permeability and net porosity interrelation has been developed in the framework of Amaefule’s technique which has been modified by newly introduced classification and clustering conceptions. Eventually, seven distinct pore geometrical units have been distinguished through implementing the hybridized genetic algorithm and k-means algorithm. Furthermore, a K-nearest neighbors (KNN) algorithm has been carried out to divide log data into the flow units and assigns them to the pre-identified FZI values. Besides, a cross between the ε-SVR model, a supervised learning machine, and the Harmony Search algorithm has been used to estimate directly permeability. To select the optimum combination of the involved logging parameters in the ε-SVR model and reduce the dimensionality problem, a principle component analysis (PCA) has been implemented on Well#1 data set. The result of PCA illustrates parameters, such as permeability, the transit time of sonic wave, resistivity of the unflashed zone, neutron porosity, photoelectric index, spectral gamma-ray, and bulk density, which possess the highest correlation coefficient with first derived PC. In line with previous studies, the findings will be compared with empirical methods, Coates–Dumanior, and Timur methods, which both have been launched into these wells. Overall, it is obvious to conclude that the ε -SVR model is undeniably the superior method with the lowest mean square error, nearly 4.91, and the highest R-squared of approximately 0.721. On the contrary, the transform relationship of porosity and permeability has remarkably the worst results in comparison with other models in error (MSE) and accuracy (R2) of 128.73 and 0.116, respectively.
Characterization of barite reserves in Nigeria for use as weighting agent in drilling fluid
Authors: Afolayan David Oluwasegun , Adetunji Adelana Rasak , Onwualu Azikiwe Peter , Ogolo Oghenerume , Amankwah Richard Kwasi
Published: June 2021

Successful drilling operations are dependent on the properties of the drilling fluid used to drill wells. Barite is used as a weighting agent during the preparation of drilling fluid. Over the years, oil and gas industry in Nigeria has been depending mainly on imported barite for drilling operations, whereas the country has huge deposits of barite. There is the need to assess the properties of the locally sourced barite for their suitability in drilling fluid formulation. This study presents the local processing methods of barite and examines the crude and on-the-site processed barite’s physio-chemical properties. These parameters were compared with American Petroleum Institute and Department of Petroleum Resources standards. XRD results show that on-the-site beneficiated barite has 87.79% BaSO4, 6.66% silica, 0.03% total soluble salt, 1.39% Fe2O3, and 1.603% heavy metals. Chemical analysis indicated that the pH, moisture content, metallic content such as Ca, Pb, Zn, Mg, Cu, and Cd minerals, and extractable carbonates were within the standard specified for usage as a drilling fluid weighting agent. The analysed crude barite samples were basic, within the pH of 8.3 and 8.6. Locally processed barite has lower Fe, Pb, Cd, and Cu content compared to industrially accepted barite. The specific gravity increased from 4.02 ± 0.07 to 4.15 ± 0.13, and the hardness reduced potentially from 5 Mohr to 3.5 Mohr on the hardness scale. The amount of impurities was sufficiently low, and the specific gravity of the samples improved to meet the needs of any drilling operation and compare favourably with industrially accepted barite.
Well logging data interpretation for appraising the performance of Alam El-Bueib reservoir in Safir Oil Field, Shushan Basin, Egypt
Authors: Elhossainy Mohamed Mahmoud , Basal Ahmed Kamal , ElBadrawy Hussein Tawfik , Salam Sobhy Abdel , Sarhan Mohammad Abdelfattah
Published: June 2021

This paper presents different well log data interpretation techniques for evaluating the reservoir quality for the sandstone reservoir of the Alam El-Bueib-3A Member in Safir-03 well, Shushan Basin, Egypt. The evaluation of the available well log data for the Alam El-Bueib-3A Member in this well indicated high quality as oil-producing reservoir between depths 8108–8133 ft (25 ft thick). The calculated reservoir parameters possess shale volume less than or equal to 9% indicating the clean nature of this sandstone interval, water saturation values range from 10 to 23%, and effective porosity varies between 19 and 23%. Bulk volume of water is less than 0.04, non-producing water (SWirr) saturation varies between 10 and 12%, and permeability ranges from 393 to 1339 MD reflecting excellent reservoir quality. The calculated BVW values are less than the minimum (BVWmin = 0.05) reflecting clean (no water) oil production, which was confirmed through the drill stem test (DST). The relative permeabilities to both water and oil are located between 0.01–0 and 1.0–0.5, respectively. The water cut is fairly low where it ranges between 0 and 20%. Additionally, the water saturation values are less than the critical water saturation (Scw = 29.5%) which reflects that the whole net pay will flow hydrocarbon, whereas the water phase will remain immobile. This was confirmed with reservoir engineering through the DST.