bluuebunny/crossref_metadata_2025 huggingface dataset:
The middle Cretaceous (110–94 Ma) evolution of Tangza Basin in the western Tibetan Plateau and implications for initial topographic growth of northern Lhasa
Authors: Han Xu , Dai Jin-Gen , Lin Jie , Xu Shi-Ying , Liu Bo-Rong , Wang Ya-Nan , Wang Cheng-Shan
Published: October 2020

Reconstruction of Cretaceous geological evolution of Tibetan Plateau growth is critical for assessing the effect of India-Asia collision on the formation of its high elevation. However, Cretaceous topographic evolution and geodynamic mechanism in northern Lhasa remain ambiguous. Here we present results from sedimentology, zircon U-Pb ages, and detrital Cr-spinel composition of the Tangza Formation in the western part of northern Lhasa. Sedimentary lithofacies document that orbitolinid foraminifera–limestone beds were deposited in a shallow-marine setting, while clastic rocks accumulated in an alluvial fan during the middle Cretaceous. Zircon U-Pb ages of interbedded volcanic rocks place a robust constraint on the initiation of clastic rock deposition at ca. 106 Ma. Sandstones are enriched lithic fragments with abundant volcanic grains. U-Pb ages of detrital zircon display a prominent age population at 101–130 Ma with a 120 Ma peak. These data indicate that the clastic rocks were mainly derived from northern Lhasa, including an Early Cretaceous magmatic arc. Sedimentary and provenance characteristics are most consistent with deposition in a local foreland basin. The activation of south-vergent local thrusting may be responsible for loading of the Tangza foreland basin. This thrust faulting may be associated with crustal shortening induced by the continuous convergence of Lhasa and Qiangtang since collision initiated during the Early Cretaceous. The initial uplift of western and central parts of northern Lhasa and eastern Gangdese arc occurred at ca. 106 Ma, while the widespread uplift of northern and central Lhasa probably initiated at ca. 92 Ma. The mid–Late Cretaceous uplift in Lhasa was significantly earlier than the early Cenozoic India-Asia collision.
Breaking bad news: what parents would like you to know
Authors: Brouwer Marije A , Maeckelberghe Els L M , van der Heide Agnes , Hein Irma M , Verhagen Eduard A A E
Published: October 2020

Objective

Breaking bad news about life-threatening and possibly terminal conditions is a crucial part of paediatric care for children in this situation. Little is known about how the parents of children with life-threatening conditions experience communication of bad news. The objective of this study is to analyse parents’ experiences (barriers and facilitators) of communication of bad news.

Design

A qualitative study consisting of a constant comparative analysis of in-depth interviews conducted with parents.

Setting

The Netherlands.

Participants

Sixty-four parents—bereaved and non-bereaved—of 44 children (aged 1–12 years, 61% deceased) with a life-threatening condition.

Interventions

None.

Results

Based on parents’ experiences, the following 10 barriers to the communication of bad news were identified: (1) a lack of (timely) communication, (2) physicians’ failure to ask parents for input, (3) parents feel unprepared during and after the conversation, (4) a lack of clarity about future treatment, (5) physicians’ failure to voice uncertainties, (6) physicians’ failure to schedule follow-up conversations, (7) presence of too many or unknown healthcare professionals, (8) parental concerns in breaking bad news to children, (9) managing indications of bad news in non-conversational contexts, and (10) parents’ misunderstanding of medical terminology.

Conclusions

This study shows healthcare professionals how parents experience barriers in bad news conversations. This mainly concerns practical aspects of communication. The results provide practical pointers on how the communication of bad news can be improved to better suit the needs of parents. From the parents’ perspective, the timing of conversations in which they were informed that their child might not survive was far too late. Sometimes, no such conversations ever took place.
Neonatal admission and mortality in babies born in UK alongside midwifery units: a national population-based case-control study using the UK Midwifery Study System (UKMidSS)
Authors: Rowe Rachel , Soe Aung , Knight Marian , Kurinczuk Jennifer J
Published: October 2020

Objectives

To determine the incidence of and risk factors for neonatal unit admission, intrapartum stillbirth or neonatal death without admission, and describe outcomes, in babies born in an alongside midwifery unit (AMU).

Design

National population-based case-control study.

Method

We used the UK Midwifery Study System to identify and collect data about 1041 women who gave birth in AMUs, March 2017 to February 2018, whose babies were admitted to a neonatal unit or died (cases) and 1984 controls from the same AMUs. We used multivariable logistic regression, generating adjusted OR (aOR) with 95% CIs, to investigate maternal and intrapartum factors associated with neonatal admission or mortality.

Results

The incidence of neonatal admission or mortality following birth in an AMU was 1.2%, comprising neonatal admission (1.2%) and mortality (0.01%). White ‘other’ ethnicity (aOR=1.28; 95% CI=1.01 to 1.63); nulliparity (aOR=2.09; 95% CI=1.78 to 2.45); ≥2 previous pregnancies ≥24 weeks’ gestation (aOR=1.38; 95% CI=1.10 to 1.74); male sex (aOR=1.46; 95% CI=1.23 to 1.75); maternal pregnancy problem (aOR=1.40; 95% CI=1.03 to 1.90); prolonged (aOR=1.42; 95% CI=1.01 to 2.01) or unrecorded (aOR=1.38; 95% CI=1.05 to 1.81) second stage duration; opiate use (aOR=1.31; 95% CI=1.02 to 1.68); shoulder dystocia (aOR=5.06; 95% CI=3.00 to 8.52); birth weight <2500 g (aOR=4.12; 95% CI=1.97 to 8.60), 4000–4999 g (aOR=1.64; 95% CI=1.25 to 2.14) and ≥4500 g (aOR=2.10; 95% CI=1.17 to 3.76), were independently associated with neonatal admission or mortality. Among babies admitted (n=1038), 18% received intensive care. Nine babies died, six following neonatal admission. Sepsis (52%) and respiratory distress (42%) were the most common discharge diagnoses.

Conclusions

The results of this study are in line with other evidence on risk factors for neonatal admission, and reassuring in terms of the quality and safety of care in AMUs.
Mucinous cystadenocarcinoma of the oral tongue: malignant transformation from a mucinous cystadenoma?
Authors: Dutra Sofia , Rito Miguel , Vilares Miguel , Borges Alexandra
Published: October 2020

Mucinous cystadenocarcinoma of minor salivary glands is an extremely rare entity that has only recently been described, with a few published cases in the English literature. A 42-year-old woman with a history of a surgically excised mucinous cystadenoma of the oral tongue, presented with a painful swelling in the oral tongue slowly growing for 1 month. On clinical examination, there was a firm, relatively well-circumscribed mass in the left posterior border of the mobile tongue. Subsequent MRI scan revealed a heterogeneous lesion composed of multiple cysts separated by contrast enhancing septa, in the posterior two-thirds of the left tongue. Imaging findings were similar to those of the previously resected mass, suggesting local relapse of the primary lesion. A complete surgical excision was performed and the histopathological examination revealed typical features of a low-grade mucinous cystadenocarcinoma of minor salivary glands.
Spontaneous atraumatic knee haemarthrosis
Authors: Canbilen Sefa William , El Abed Khaldoun , Ahmad Riaz
Published: October 2020

Spontaneous knee haemarthrosis is a rare condition, most prevalent in the elderly with osteoarthritis. Recent reports have proposed that the source of bleeding is the peripheral arteries supplying the posterior horn of the lateral meniscus. In this case, a 62-year-old active man presented with acute postero-lateral left knee pain and swelling with limited weight bearing or movement of the knee. No recent history of trauma but history of lateral compartment dominant osteoarthritis and arthroscopic partial lateral meniscectomy of left knee. Aspiration showed a large haemarthrosis and following an MRI scan displaying large areas of full thickness chondral loss, complex tearing of lateral meniscus and loose bodies, the patient had an arthroscopy, washout, debridement of osteochondral tibial defect and diathermy of suspected bleeding point. This report supports the peripheral arteries supplying the posterior horn of the lateral meniscus as the source of bleeding in spontaneous haemarthrosis of the knee.
Acute upper gastrointestinal bleed in the puerperium following weight reduction surgery
Authors: Parton Julia Rhian , Ritchie Joanne
Published: October 2020

Bariatric surgery is often a definitive treatment for obesity and is increasingly being performed on women of childbearing age. While bariatric surgery may reduce the risk of obesity in pregnancy, there are new complications which can develop following these procedures. Our case describes a 31-year-old women who presented in the puerperium with a life-threatening upper gastrointestinal bleed secondary to marginal ulceration following a Roux-en-Y procedure. This case report discusses a rare case of acute upper gastrointestinal bleed in the postnatal period and highlights the risk factors and complications which may present in the obstetrical patient following bariatric surgery. With the increasing use of weight loss surgery in obese women and the associated improvement in fertility following, we must remain aware of the risks and these women should be identified at booking so that their antenatal and postnatal care can be tailored accordingly.
Vajra Bhasma, Ayurvedic medicine: a rare and unusual cause of Lyell’s syndrome and its successful management
Authors: Channabasappa Shivakumar M , Gupta Bhavna , Dharmappa Shruthi
Published: October 2020

Toxic epidermolysis necrosis (TEN) or Lyell syndrome is a potentially life-threatening immunological adverse skin disease, which mostly occurs secondary to the intake of an offending drug. It commonly manifests as a widespread exfoliating bullous lesion in skin and mucous membrane mimicking superficial burns and may result in hypovolemic and/or septic shock. Authors report an unusual case of Lyell’s syndrome in a 42-year-old woman, secondary to the intake of Ayurveda medicine ‘Vajra Bhasma’ (Diamond Ash) prescribed by an Ayurveda physician for treatment of her trigeminal neuralgia. After 8th day of continuous medication intake, she had prodromal illness and rapidly developing exfoliative skin lesion extended over 80% of total body surface area, breathing difficulty, dizziness and anuria. The case was successfully managed by timely diagnosis, adequate hydration and administration of immunoglobulins. After 17 days, the skin epithelium regenerated, and she improved clinically with some depigmented lesions at discharge, which were normalised without any sequel during her further follow-up visits in hospital. Identification and withdrawal of the suspected drug, adequate resuscitation and early immunoglobulin administration are critical in management of TEN.
Aflibercept for age-related macular degeneration: 4-year outcomes of a ‘treat-and-extend’ regimen with exit-strategy
Authors: Jaggi Damian , Nagamany Thanoosha , Ebneter Andreas , Munk Marion , Wolf Sebastian , Zinkernagel Martin
Published: October 2020

Aim

To report long-term outcomes on best-corrected visual acuity (BCVA) and treatment intervals with a treat-and-extend (T&E) regimen in patients with neovascular age-related macular degeneration (nAMD).

Methods

This observational study included treatment-naïve patients with nAMD, treated with aflibercept. A specific T&E protocol without a loading phase and predefined exit criteria was administered. After reaching predefined ‘exit-criteria’, the treatment period was complete, and patients were observed three monthly.

Results

Eighty-two patients with a follow-up period of ≥2 years were included. BCVA (mean±SD, ETDRS letters) increased from 51.9±25.2 at baseline to 63.7±17.7 (p<0.0001) at 1 year, 61.7±18.5 (p<0.0001) at 2 years, 62.4±19.5 (p<0.0001, n=61) at 3 years and remained insignificantly higher than baseline at 4 years at 58.5±24.3 (p=0.22). Central subfield thickness (mean±SD, μm) decreased significantly from 387.5±107.6 (p<0.0001) at baseline to 291.9±65.5 (p<0.0001) at 1 year, and remained significantly lower until 4 years at 289.0±59.4 (p<0.0001). Treatment intervals (mean±SD, weeks) could be extended up to 9.3±3.1 weeks at 1 year and remained at 11.2±3.5 weeks at 4 years. Twenty-nine (35%) patients reached exit criteria and continued with three monthly observation only.

Conclusions

After 4 years of treatment, initial vision gains were maintained with a reasonable treatment burden, even without an initial loading phase. Our results on functional outcomes are comparable with large controlled studies.
Preparing a deployed role 3 medical treatment facility for COVID-19 in Afghanistan
Authors: Lewin Ivor J S , Krasucki D J , Stuart R P , White B K
Published: October 2020

The Craig Joint Theater Hospital at Bagram Airfield is the coalition role 3 facility for the North Atlantic Treaty Organization-led Operation RESOLUTE SUPPORT in northern Afghanistan. The onset of the global COVID-19 pandemic in early 2020 presented the challenges of limiting viral transmission, disease force protection, specific protection of healthcare workers and management of patients with COVID-19, all while continuing to provide high-quality care for battlefield trauma. The estimated COVID-19 threat led to the introduction of enhanced force protection measures across the Combined Joint Operations Area-Afghanistan. Surveillance testing of high-risk groups at coalition locations was established. Non-essential movements were restricted and quarantine periods instigated. Protection of healthcare workers and patients was improved with enhanced personal protective equipment as well as structural, procedural and personnel changes across the role 3 facility in order to limit viral exposure and transmission. This occurred in a resource-limited environment without degrading overall clinical capability.
Costing the impact of interventions during pregnancy in the UK: a systematic review of economic evaluations
Authors: Relph Sophie , Delaney Louisa , Melaugh Alexandra , Vieira Matias C , Sandall Jane , Khalil Asma , Pasupathy Dharmintra , Healey Andy
Published: October 2020

Objective

The aim of this review was to summarise the current evidence on the costing of resource use within UK maternity care, in order to facilitate the estimation of incremental resource and cost impacts potentially attributable to maternity care interventions.

Methods

A systematic review of economic evaluations was conducted by searching Medline, the Health Management Information Consortium, the National Health Service (NHS) Economic Evaluations Database, CINAHL and National Institute for Health and Care Excellence (NICE) guidelines for economic evaluations within UK maternity care, published between January 2010 and August 2019 in the English language. Unit costs for healthcare activities provided to women within the antenatal, intrapartum and postnatal period were inflated to 2018–2019 prices. Assessment of study quality was performed using the Quality of Health Economic Analyses checklist.

Results

Of 5084 titles or full texts screened, 37 papers were included in the final review (27 primary research articles, 7 review articles and 3 economic evaluations from NICE guidelines). Of the 27 primary research articles, 21 were scored as high quality, 3 as medium quality and 3 were low quality. Variation was noted in cost estimates for healthcare activities throughout the maternity care pathway: for midwife-led outpatient appointment, the range was £27.34–£146.25 (mean £81.78), emergency caesarean section, range was £1056.44–£4982.21 (mean £3508.93) and postnatal admission, range was £103.00–£870.10 per day (mean £469.55).

Conclusions

Wide variation exists in costs applied to maternity healthcare activities, resulting in challenges in attributing cost to maternity activities. The level of variation in cost calculations is likely to reflect the uncertainty within the system and must be dealt with by conducting sensitivity analyses. Nationally agreed prices for granular unit costs are needed to standardise cost-effectiveness evaluations of new interventions within maternity care, to be used either for research purposes or decisions regarding national intervention uptake.

PROSPERO registration number

CRD42019145309.
Improving quality in clinical placement studies in nursing homes (QUALinCLINstud): the study protocol of a participatory mixed-methods multiple case study design
Authors: Laugaland Kristin Alstveit , Thorsen Gonzalez Marianne , McCormack Brendan , Skovdahl Kirsti-Iren , Slettebø Åshild , Billett Stephen , Akerjordet Kristin
Published: October 2020

Introduction

Improved quality in clinical supervision and assessment of student nurses in nursing home clinical placements is vitally important to effective recruitment and preparation for this healthcare sector. Knowledge regarding supervision and assessment practices within these settings is limited. Also, knowledge of evolving e-learning tools on the quality and effectiveness of these educational practices seems to be absent.

Methods and analysis

The aim of the “Improving quality in clinical placement studies in nursing homes” (QUALinCLINstud) study is to develop and evaluate how a web-based programme can optimise supervision, assessment and learning during nursing home placements. The study applies a participatory, mixed-methods case study design, organised in four work packages (WPs). WP1 will explore how the nurse education institution address the quality of student nurses’ clinical placements in nursing homes. In WP2, clinical supervision and assessment practices will be explored, and described from multiple stakeholder perspectives. In WP3, based on the findings from WP1 and WP2, a web-based pedagogical supervision and assessment programme will be developed through a developmental co-productive process between nurse education institutions, practice settings and student nurses. In WP4, the web-based programme will be pilot-tested and evaluated through a mixed-methods approach. A range of data collection procedures will be used throughout the project, for example, questionnaires, interviews, observations and workshops.

Ethics and dissemination

The ethical conduct of the study is approved by the Norwegian Centre for Research Data (2018/61309 and 489776). The results will be disseminated through scientific articles, three PhD theses, presentations at national and international conferences, and through publicly accessible trade journals and newspapers. The results will generate knowledge to inform supervision and assessment practices in nursing home placements. Moreover, the study will generate knowledge concerning the developmental process of a web-based supervision and assessment programme, and the value of e-learning tools applied in clinical nursing education.
Use of data from the Vascular Quality Initiative registry to support regulatory decisions yielded a high return on investment
Authors: Cronenwett Jack L , Avila-Tang Erika , Beck Adam W , Bertges Daniel , Eldrup-Jorgensen Jens , Resnic Frederic S , Radoja Nadezda , Sedrakyan Art , Schick Andreas , Smale Josh , Bloss Roberta A , Phillips Peter , Hasenbank Melissa , Wang Shengchun , Marinac-Dabic Danica , Pappas Gregory
Published: October 2020

Background

Real-world data (RWD) from the Society for Vascular Surgery Vascular Quality Initiative (VQI) registry has been used to support US Food and Drug Administration (FDA) regulatory decisions regarding vascular devices. The variables of cost and time needed for these registry-based studies have not been previously compared to traditional, independent, industry studies that would otherwise have been conducted to support regulatory decisions.

Objectives

To determine the potential value (cost and time saving and return on investment) created by device evaluation studies using the VQI registry infrastructure.

Methods

We compared studies that used data from the VQI registry with estimated costs of independent industry studies (counterfactual studies) using an established model using design specifications determined by FDA reviewers.

Results

We analyzed the initial six studies evaluating vascular devices for regulatory decisions using data from the VQI registry that generated evidence for four device manufacturers. Return on investment for these studies was estimated to be 143% and cost saving as 59% based on an actual per patient (with 5-year follow-up) cost of US$11K using VQI data versus US$26K from the counterfactual when averaged across all studies. Significant enrollment time savings (45%–71%) were also realized compared with industry-based estimates.

Conclusions

The use of RWD from the VQI registry in this study and the transcatheter valve treatment coordinated registry network in a prior study indicates that substantial value was added to device evaluation projects by the reuse of registry data, with additional potential savings if linked claims data can be used instead of costly long-term in-person follow-up.
Standalone performance of artificial intelligence for upper GI neoplasia: a meta-analysis
Authors: Arribas Julia , Antonelli Giulio , Frazzoni Leonardo , Fuccio Lorenzo , Ebigbo Alanna , van der Sommen Fons , Ghatwary Noha , Palm Christoph , Coimbra Miguel , Renna Francesco , Bergman J J G H M , Sharma Prateek , Messmann Helmut , Hassan Cesare , Dinis-Ribeiro Mario J
Published: October 2020

Objective

Artificial intelligence (AI) may reduce underdiagnosed or overlooked upper GI (UGI) neoplastic and preneoplastic conditions, due to subtle appearance and low disease prevalence. Only disease-specific AI performances have been reported, generating uncertainty on its clinical value.

Design

We searched PubMed, Embase and Scopus until July 2020, for studies on the diagnostic performance of AI in detection and characterisation of UGI lesions. Primary outcomes were pooled diagnostic accuracy, sensitivity and specificity of AI. Secondary outcomes were pooled positive (PPV) and negative (NPV) predictive values. We calculated pooled proportion rates (%), designed summary receiving operating characteristic curves with respective area under the curves (AUCs) and performed metaregression and sensitivity analysis.

Results

Overall, 19 studies on detection of oesophageal squamous cell neoplasia (ESCN) or Barrett's esophagus-related neoplasia (BERN) or gastric adenocarcinoma (GCA) were included with 218, 445, 453 patients and 7976, 2340, 13 562 images, respectively. AI-sensitivity/specificity/PPV/NPV/positive likelihood ratio/negative likelihood ratio for UGI neoplasia detection were 90% (CI 85% to 94%)/89% (CI 85% to 92%)/87% (CI 83% to 91%)/91% (CI 87% to 94%)/8.2 (CI 5.7 to 11.7)/0.111 (CI 0.071 to 0.175), respectively, with an overall AUC of 0.95 (CI 0.93 to 0.97). No difference in AI performance across ESCN, BERN and GCA was found, AUC being 0.94 (CI 0.52 to 0.99), 0.96 (CI 0.95 to 0.98), 0.93 (CI 0.83 to 0.99), respectively. Overall, study quality was low, with high risk of selection bias. No significant publication bias was found.

Conclusion

We found a high overall AI accuracy for the diagnosis of any neoplastic lesion of the UGI tract that was independent of the underlying condition. This may be expected to substantially reduce the miss rate of precancerous lesions and early cancer when implemented in clinical practice.
Microbiome-derived metabolome as a potential predictor of response to cancer immunotherapy
Authors: Malczewski Agnieszka Beata , Navarro Severine , Coward Jermaine IG , Ketheesan Natkunam
Published: October 2020

Cancer immunotherapy with checkpoint blockade has become standard of care treatment for numerous cancer types. Despite this, robust predictive biomarkers are lacking. There is increasing evidence that the host microbiome is a predictor of immunotherapy response, although the optimal host microbiome has not been defined. Metabolomics is a new area of medicine that aims to analyze the metabolic profile of a biological system. The microbiome-derived metabolome (fecal and serum) represents the end products of microbial metabolism and these may be functionally more important than the distinct bacterial species that comprise a favorable microbiome. Short-chain fatty acids (SCFA) are metabolites produced by gut microbiota and have a role in T cell homeostasis, including differentiation of regulatory T cells. Recent studies have confirmed differential expression of SCFA for immunotherapy responders compared with non-responders. We propose that the microbiome metabolome, with a focus on SCFA may be a novel predictive biomarker for immunotherapy efficacy.
Gestaticide: killing the subject of the artificial womb
Authors: Rodger Daniel , Colgrove Nicholas , Blackshaw Bruce Philip
Published: October 2020

The rapid development of artificial womb technologies means that we must consider if and when it is permissible to kill the human subject of ectogestation—recently termed a ‘gestateling’ by Elizabeth Chloe Romanis—prior to ‘birth’. We describe the act of deliberately killing the gestateling asgestaticideand argue that there are good reasons to maintain that gestaticide is morally equivalent to infanticide, which we consider to be morally impermissible. First, we argue that gestaticide is harder to justify than abortion, primarily because the gestateling is completely independent of its biological parents. Second, we argue that gestaticide is morally equivalent to infanticide. To demonstrate this, we explain that gestatelings are born in a straightforward sense, which entails that killing them is as morally serious as infanticide. However, to strengthen our overall claim, we also show that if gestatelings are not considered to have been born, killing them is still equivalent to killing neonates with congenital anomalies and disabilities, which again is infanticide. We conclude by considering how our discussion of gestaticide has implications for the permissibility of withdrawing life-sustaining treatment from gestatelings.
Eye lens Δ14C validates otolith-derived age estimates of Gulf of Mexico reef fishes
Authors: Patterson William F. , Barnett Beverly K. , TinHan Thomas C. , Lowerre-Barbieri Susan K.
Published: October 2020

We tested whether Δ14C values of eye lens protein (crystallin) formed in early life could be utilized to validate marine bony fish age estimates via the bomb radiocarbon chronometer. The slope of the relationship between red snapper (Lutjanus campechanus; n = 8; 0 to 27 years old), otolith and eye lens core Δ14C values was not significantly different than 1, which was also true for seven additional reef fish species (n = 21; 0 to 24 years old). Results demonstrate eye lens core Δ14C can be utilized to validate age estimates of marine fishes, which will be useful in numerous age validation applications.
Behavioural response of sea lamprey (Petromyzon marinus) to acoustic stimuli in a small stream
Authors: Heath Victoria L.S. , Miehls Scott , Johnson Nicholas , Higgs Dennis M.
Published: October 2020

Sea lamprey (Petromyzon marinus) are invasive in the Laurentian Great Lakes and parasitically feed on valued fishes. Migration barriers and selective pesticides are used to control sea lamprey, but there is a desire to develop additional control tools such as traps with nonphysical deterrents. Sound has been used as a deterrent for other invasive species, but its potential for manipulating sea lamprey behavior in natural stream conditions remains untested. Here, behavioral responses of upstream-migrating adult sea lamprey in response to low frequency sounds of 70 or 90 Hz was tracked in a small stream (8 m wide) using passive integrated transponder (PIT) telemetry. The low frequency sounds shifted sea lamprey distribution, with up to 30% more sea lamprey detected on PIT antennas without sound compared with PIT antennas with sound playing. Future studies could continue testing low frequency sounds in larger rivers with larger speakers for use as a natural deterrent at sea lamprey barriers to push sea lamprey toward traps.
A new symmetry of the spatially flat Einstein–Friedmann equations
Authors: Dussault Steve , Faraoni Valerio
Published: October 2020

We report a new symmetry of the Einstein–Friedmann equations for spatially flat Friedmann- Lemaître-Robertson-Walker universes. We discuss its application to barotropic perfect fluids and its use as a solution-generating technique for scalar field universes.
Global Bifurcation of Stationary Solutions for a Volume-Filling Chemotaxis Model with Logistic Growth
Authors: Dong Yaying , Li Shanbing
Published: October 2020

In this paper, we show how the global bifurcation theory for nonlinear Fredholm operators (Theorem 4.3 of [Shi & Wang, 2009]) and for compact operators (Theorem 1.3 of [Rabinowitz, 1971]) can be used in the study of the nonconstant stationary solutions for a volume-filling chemotaxis model with logistic growth under Neumann boundary conditions. Our results show that infinitely many local branches of nonconstant solutions bifurcate from the positive constant solution [Formula: see text] at [Formula: see text]. Moreover, for each [Formula: see text], we prove that each [Formula: see text] can be extended into a global curve, and the projection of the bifurcation curve [Formula: see text] onto the [Formula: see text]-axis contains [Formula: see text].
An Eco-Epidemic Predator–Prey Model with Allee Effect in Prey
Authors: Shaikh Absos Ali , Das Harekrishna
Published: October 2020

This article describes the dynamics of a predator–prey model with disease in predator population and prey population subject to Allee effect. The positivity and boundedness of the solutions of the system have been determined. The existence of equilibria of the system and the stability of those equilibria are analyzed when Allee effect is present. The main objective of this study is to investigate the impact of Allee effect and it is observed that the system experiences Hopf bifurcation and chaos due to Allee effect. The results obtained from the model may be useful for analyzing the real-world ecological and eco-epidemiological systems.
Guaranteed Estimates for the Length of Branches of Periodic Orbits for Equivariant Hopf Bifurcation
Authors: Hooton Edward , Balanov Zalman , Rachinskii Dmitrii
Published: October 2020

Connected branches of periodic orbits originating at a Hopf bifurcation point of a differential system are considered. A computable estimate for the range of amplitudes of periodic orbits contained in the branch is provided under the assumption that the nonlinear terms satisfy a linear estimate in a ball. If the estimate is global, then the branch is unbounded. The results are formulated in an equivariant setting where the system can have multiple branches of periodic orbits characterized by different groups of symmetries. The nonlocal analysis is based on the equivariant degree method, which allows us to handle both generic and degenerate Hopf bifurcations. This is illustrated by examples.
Simulation of cancer prognosis
Authors: Sun Hao , Lee James D.
Published: October 2020

Most mechanobiology phenomena commonly involve biological growth and deformation. In this work, we propose an innovative model of cancerous growth which posits that an expandable tumor can be described as a poroelastic medium consisting of solid and fluid components. In our biologically informed mechanical description of tumor growth dynamics, we derive the governing equations of the tumor’s growth and incorporate them with large deformation and materially nonlinear constitutive equations to improve the accuracy and efficiency of our simulation. Meanwhile, the dynamic finite element equations (DFE) for coupled displacement field and pressure field are formulated and solved. The 3-dimensional porous model is introduced. Numerical results are presented and discussed.
The Juliet Field, Block 47/14b, UK North Sea
Authors: Offer D. J.
Published: October 2020

The abandoned Juliet gas field is a small, highly compartmentalized, accumulation situated south and east of the Amethyst Gas Field. It was discovered in 2008 by well 47/14b-10 and flowed first gas on 5 January 2014. The field consists of at least two culminations within a very low-relief east–west-orientated fault-bounded anticline. The reservoir comprises aeolian sandstones of the Permian, Rotliegend Group, Leman Sandstone Formation. Reservoir quality varies from good to moderate, with a high production rate achieved from horizontal wells.

Seismic time-to-depth conversion is affected by Quaternary seabed channels, chalk burial history and a rapid thickening in the Basalanhydrit Formation located over the east of the field, associated with the edge of the Zechstein Basin.

Gas-in-place at pre-development was expected to be 105 bcf, with reserves of 67 bcf. The field was developed using two horizontal wells and a subsea tie-back to the Pickerill Field, 22 km to the east. Since development, the field appears to be more compartmentalized than initially expected.
The Golden Eagle, Peregrine and Solitaire fields, Blocks 14/26a and 20/01, UK North Sea
Authors: Pinnock S. J. , Dutton D. M.
Published: October 2020

The Golden Eagle Field is located 18 km north of the Buzzard Field in the Moray Firth, and consists of oil accumulations in the Lower Cretaceous Punt and Upper Jurassic Burns Sandstone members. The development area comprises three fields, Golden Eagle, Peregrine and Solitaire, but up to 90% of the oil-in-place and ultimate recovery are in Golden Eagle. The two satellite fields are primarily structural closures, while the Golden Eagle Field reservoirs have a major element of stratigraphic pinchout. Production commenced in October 2014 and approximately 140 MMbbl of recoverable oil is anticipated over its field life from the 19 development wells (14 producers and 5 injectors) that form the initial development phase. Production performance to date has exceeded expectations, aided through the use of completions that provide zonal control of the reservoir units which has successfully supported reservoir management and improved sweep efficiency.

A number of significant lessons have been learned during the early stages of the field life from the integration of dynamic data (real-time downhole fibre-optic reservoir monitoring instruments, inter- and intra-well tracers, and well interference tests) and seismic data improvements (post-start-up acquisition of high-density ocean-bottom node seismic and depth-conversion improvements).
The Laggan and Tormore fields, Blocks 206/1 and 205/5, UK Atlantic Margin
Authors: Clark J. , Matthews P. , Parry C. , Rowlands M. , Tessier A.
Published: October 2020

The Laggan and Tormore fields are found within the Flett sub-basin of the Faroe–Shetland Basin. Situated 120 km west of the Shetland Islands in 600 m water depth, they are part of the deepest subsea development in the UK to date with a 143 km subsea tie-back to onshore facilities.

The reservoirs are found within the T35 biostratigraphic sequence of the Paleocene Vaila Formation and comprise sand-rich turbiditic channelized lobes with good reservoir properties, separated by metric to decimetric shale packages. Laggan is a gas-condensate field, whereas Tormore fluid is a richer gas with a saturated oil rim. Seismic reservoir characterization is a key to the field development where differentiation of fluid type proved challenging. Both fields came on stream in 2016 as part of the Greater Laggan area development scheme.
The Crosby Warren Field, Block DL001, UK Onshore
Authors: Johnson M. , Evans G. J.
Published: October 2020

The Crosby Warren Field is located onshore the UK, south of the Humber Estuary. It was discovered by RTZ Oil & Gas with the CW-1 (L46/12-3) well in 1986. The oil reservoir is Carboniferous, Namurian, Beacon Hill Flags sandstone, with gas found in Namurian sandstones of the Rough Rock, and the discovery well originally flowed waxy 40° API oil at rates of 45 bopd, which increased to nearly 700 bopd following fracture stimulation. The Beacon Hill Flags are a 10 m-thick group of laminated sandstones within a substantial gross thickness of sandstones, silts, muds and occasional thin claystones. The expected ultimate recovery for the field will be about 0.9 MMbbl of oil and 0.7 bcf of gas. Almost all of the oil and gas have already been recovered, and end of life for the field is expected to be in 2022.
The Britannia Field, Blocks 15/29, 15/30, 16/26 and 16/27, UK North Sea
Authors: Camm M. , Armstrong L. E. , Patel A.
Published: October 2020

The Lower Cretaceous Britannia Field development is one of the largest and most significant undertaken on the UK Continental Shelf. Production started in 1998 via 17 pre-drilled development wells and was followed by a decade of intensive drilling, whereby a further 40 wells were added. In 2000 Britannia's plateau production of 800 MMscfgd supplied 8% of the UK's domestic gas requirements.

As the field has matured, so too has its development strategy. Initial near-field development drilling targeting optimal reservoir thickness was followed by extended reach wells into the stratigraphic pinchout region. In 2014 a further strategy shift was made, moving from infill drilling to a long-term compression project to maximize existing production. During its 20-year history the Britannia Platform has undergone numerous changes. In addition to compression, production from five satellite fields has been routed through the facility: Caledonia (2003), Callanish and Brodgar (2008), Enochdhu (2015) and Alder (2016). A new field, Finlaggan, is due to be brought through Britannia's facilities in 2020, helping to maximize value from the asset for years to come.

As Britannia marks 20 years of production it has produced
c.
600 MMboe – surpassing the original ultimate recoverable estimate of
c.
570 MMboe – and is still going strong today.
The Cygnus Field, Blocks 44/11a and 44/12a, UK North Sea
Authors: Dredge Ian , Marsden Gary
Published: October 2020

The Cygnus Field is located in Blocks 44/11a and 44/12a of the UK Southern North Sea. The field was first discovered in 1988 as a tight lower Leman Sandstone Formation gas discovery by well 44/12- 1. After the licences had sat idle for several years, GDF Britain (now Neptune E&P UK Ltd) appraised the field from 2006 to 2010. During the appraisal phase, the lower Leman Sandstone was found to be of better quality than first discovered and the gas-bearing lower Ketch Member reservoir was also encountered. The field development was sanctioned in 2012.

The field has been developed from two wellhead platforms targeting Leman Sandstone and Ketch Member reservoirs. Five main fault blocks have been developed, with two wells in each fault block planned in the field development plan. The wells are long horizontal wells completed with stand-alone sand screens. At the time of writing, the production plateau is 320 MMscfgd (266 MMscfgd when third-party constraints apply), producing from nine wells with the final production well to be drilled.
The Erskine Field, Block 23/26b, UK North Sea
Authors: Robertson I.
Published: October 2020

The Erskine high-pressure–high-temperature gas condensate field was the first such field developed in the UK Continental Shelf. Since production started in 1997, the field has produced over 350 bcf of gas and 70 MMbbl of condensate. The reservoir pressure has depleted from an initial pressure of 960 bar (13 920 psi) down to 140–400 bar (2030–5800 psi), resulting in some compaction and sand production in some of the wells. Free water production has led to the formation of wellbore scale, which has required interventions to remove.

The reservoirs are sandstones of the Jurassic Puffin, Pentland and Heather formations. Estimates of hydrocarbons in place made using production and pressure data compare favourably with the initial estimates made during field development planning, although the Pentland Formation volume is some 20% below the sanction estimate.

Several major field outages have occurred, such as a condensate fire in 2010 and a blockage of the multiphase export pipeline in 2007. In addition, the field has experienced flow assurance problems related to scale and wax deposition. A new pipeline section was installed in 2018 to bypass a full pipeline blockage which occurred due to wax deposition.
The Howe and Bardolino fields, Blocks 22/12a and 22/13a, UK North Sea
Authors: Liebnitz S.
Published: October 2020

The Howe and Bardolino fields lie in UK Blocks 22/12a and 22/13a, respectively, on the eastern flank of the Forties–Montrose High. The Howe Field was discovered in 1987 by well 22/12a-1, and Bardolino in 1988 with well 22/13a-1ST. Both share common Jurassic reservoirs, have Upper Jurassic Kimmeridge Clay Formation top seals, require some form of lateral seal and have similar fluids. Howe has been producing relatively dry oil throughout its production life, indicating relatively good connectivity across the field area. In contrast, the Bardolino accumulation is proven to be compartmentalized. Bardolino is likely to be segmented through some fault-related mechanism.

In place volumes at the Howe Field are 46.8 MMbbl, with 17 MMbbl produced thus far through a combination of natural aquifer and solution gas cap drive by subsea development well 22/12a-9Z. In place volumes at the Bardolino Field are 11.2 MMbbl, with 1.1 MMbbl produced to date through depletion drive by a subsea development well 22/13a-8. This represents recovery rates of 35% for Howe and 10% for Bardolino to date. In place volumes for the undeveloped Pentland Formation at Howe are 5 MMbbl. In place estimates for the undeveloped Kimmeridge Clay Formation sandstones at Bardolino are 8 MMbbl.
The Douglas Field, Block 110/13b, UK East Irish Sea
Authors: Bunce J.
Published: October 2020

The Douglas Field is located in Block 110/13b in the East Irish Sea. It was the first oilfield to be discovered and produced in the region, having been found in 1990 and brought on stream in January 1996. The field structure comprises a series of north–south-trending, tilted, extensional fault blocks. The reservoir interval is the Triassic Ormskirk Sandstone Formation comprising good quality aeolian and fluvial sandstones. The field is relatively shallow, with the top reservoir at
c.
2120 ft true vertical depth subsea. The hydrocarbon is a light oil of 44°API gravity with a maximum column height of
c.
400 ft. The Douglas Field contains an estimated stock tank oil in place of 248 MMbbl and was developed with 22 wells: 15 producers, six water injectors and a single sour gas and condensate disposal well. Electric submersible pumps are installed in oil producers for artificial lift and water injection was utilized from field start-up for pressure maintenance. A water-alternating-gas pilot was implemented on the field in 2017 as an enhanced oil recovery scheme. The field currently produces at a rate of
c.
4000 bopd, with approximately 90% water cut. The field has produced 103 MMbbl to date, giving a current oil recovery of
c.
41%.
The Endurance CO
2
storage site, Blocks 42/25 and 43/21, UK North Sea
Authors: Gluyas Jon G. , Bagudu Usman
Published: October 2020

The Endurance, four-way, dip-closed structure in UK Blocks 42/25 and 43/21 occurs over a salt swell diapir and within Triassic and younger strata. The Lower Triassic Bunter Sandstone Formation reservoir within the structure was tested twice for natural gas (in 1970 and 1990) but both wells were dry. The reservoir is both thick and high quality and, as such, an excellent candidate site for subsurface CO
2
storage.

In 2013 a consortium led by National Grid Carbon drilled an appraisal well on the structure and undertook an injection test ahead of a planned development of Endurance as the first bespoke storage site on the UK Continental Shelf with an expected injection rate of 2.68 × 10
6
t of dense phase CO
2
each year for 20 years. The site was not developed following the UK Government's removal of financial support for carbon capture and storage (CCS) demonstration projects, but it is hoped with the recent March 2020 Budget that government support for CCS may now be back on track.
Examining Chinese and American Online Learning
Authors: Stonier Francis , Liu Geping , Yu Liang
Published: October 2020

Through a collaborative opportunity, educators from the U.S. and China share examples and comparisons of online learning, or distance education, occurring in their respective nations. This article draws from experience on both sides to explore online course design, learning management systems (LMS), and course evaluation. In all situations, the universities had well developed online offerings for students. However, as LMS and support were similar in the U.S. when compared to Chinese counterparts, variance was visible in a number of areas. Discussion stems from the perceived strengths and weaknesses of distance education foundations, training, and support. The most notable differences were found in programs offered in an online format, the scope that the platform encompassed, and mandatory evaluation of course content.
High-Performance Polypyrrole Coated Filter Paper Electrode for Flexible All-Solid-State Supercapacitor
Authors: Zhang Jiali , Chen Qing , Zhang Haixia , Hou Ying , Guo Junjie
Published: October 2020

A high-performance paper electrode is fabricated through coating polypyrrole (PPy) on ordinary laboratory filter paper via a traditional interfacial polymerization method with perchloric acid (HClO4) as a dopant. Owing to the superior mechanical flexibility and environmental stability of the free standing PPy paper, the robust electrode displays an ultrahigh capacitance of 1650 mF cm−2 and remarkable cyclic stability of losing 11.66% after cycling for 10000 times in a three-electrode system. More importantly, the areal specific capacitance has only decreased by 0.08% after five months. Furthermore, by employing the synthesized PPy papers as electrodes and the PVA-H2SO4 gel as electrolyte, the assembled all-solid-state supercapacitor with an areal specific capacitance of 566.5 mF cm−2 is achieved, corresponding to an areal energy density of 38.55 μW h cm−2 and power density of 0.17 mW cm−2. These results suggest that the simple synthesis of PPy paper electrode pave a promising way to exploit flexible and durable energy storage applications.
Gyejigachulbutang (Gui‐Zhi‐Jia‐Shu‐Fu‐Tang, Keishikajutsubuto, TJ‐18) in Degenerative Knee Osteoarthritis Patients: Lessons and Responders from a Multicenter Randomized Placebo‐Controlled Double‐Blind Clinical Trial
Authors: Kim Myung Kwan , Leem Jungtae , Kim Young Il , Kim Eunseok , Park Yang Chun , Sul Jae-Uk , Jo Hee-Geun , Yoon Sang-hoon , Kim Jeeyong , Jeon Ju-Hyun , Jung In Chul
Published: October 2020

Background. Gyejigachulbutang (GUI‐ZHI‐JIA‐SHU‐FU‐TANG, GCB) is an herbal formula widely prescribed in traditional East Asian medicine practice for arthritis and muscle pain. We evaluated the efficacy and safety of GCB for degenerative knee osteoarthritis (KOA). Methods. Eighty patients with KOA were randomly assigned to the GCB group or the placebo group in a 1 : 1 ratio in two Korean medicine hospitals. Patients took GCB or placebo three times a day for 4 weeks. Primary outcome was the change in the visual analogue scale (VAS) score for knee pain from baseline to 4th week. Secondary outcomes were the change in the VAS score from baseline to 2nd week and 8th week, Korean Western Ontario and McMaster Universities Osteoarthritis Index (K‐WOMAC), European Quality of Life Five Dimensions questionnaire (EQ‐5D), and safety. Results. There was no significant difference between the compared indicators of the GCB and placebo groups. However, in subgroup analysis, GCB was effective for subjects with a BMI lower than 25 kg/m2. The dose of pain medication was significantly lower in the GCB group than in the placebo group after four weeks (p = 0.016). There were no serious adverse events in the GCB group. Conclusions. GCB was not effective in primary outcome analysis. In exploratory subgroup analysis, GCB might be effective for individuals with BMI lower than 25 kg/m2 for the treatment of degenerative KOA. GCB may also help reduce the consumption of pain medication. Furthermore, research is required for our hypothesis. This trial is registered with KCT0003024.