bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nitrification and denitrification in recirculating aquaculture systems: the processes and players
Authors: Preena Prasannan Geetha , Rejish Kumar Vattiringal Jayadradhan , Singh Isaac Sarojini Bright 
Published: March 2021

AbstractOne of the major challenges in any sustainable aquaculture production systems is the accumulation of nitrogenous waste such as ammonia and its biological nitrification products viz nitrite and nitrate. Considering the bio‐security issues, amelioration of these wastes without water exchange can be accomplished only by way of establishing in situ nitrification and denitrification through biofilters/bioreactors activated with nitrifying/denitrifying bioaugmentors. In such systems, coexistence of aerobic denitrifiers, anaerobic ammonia oxidizers (Anammox) and complete ammonia oxidizers (Comammox) together with the autotrophic nitrifiers enhance the coupled nitrification–denitrification. This promotes total nitrogen removal without external carbon supplements or additional anerobic compartment in the system. Various recirculating aquaculture systems (RAS) comprise diverse nitrifying community in biofilters/bioreactors thereby imparting distinctive nitrogen conversion in the system. Meanwhile, the structure and population dynamics of the nitrifying/denitrifying consortia are influenced by the environmental factors forming the decisive factors of the success of the processes. Accordingly, understanding the complexity of nitrifying/denitrifying community composition turns out to be a requirement to facilitate its improvised performance. In this context, the review addresses different biological nitrogen removal systems, significance of nitrification–denitrification in RAS, genetic diversity of the key players in RAS, methods of analysis of their community structure, current application and prospects of the processes in RAS.
Untreated dental disease and lung transplant waitlist evaluation time for individuals with cystic fibrosis
Authors: Alkhateeb Alaa A. , Lease Erika D. , Mancl Lloyd A. , Chi Donald L. 
Published: March 2021

AbstractAimsDental clearance is typically part of the evaluation process prior to placement on the lung transplant waiting list. Individuals with cystic fibrosis (CF) are thought to be at low risk for dental disease. We hypothesized that individuals with CF in need of lung transplantation would have lower dental disease prevalence and shorter waitlist evaluation time than individuals with non‐CF lung diseases.Methods and ResultsWe conducted a retrospective study of individuals who received a lung transplant between 2011 and 2017 at the University of Washington (Seattle, WA, USA) (N = 280). Untreated dental disease was assessed by the individual's dentist. Waitlist evaluation time was defined as the time, in days, from the initial evaluation by a transplant pulmonologist to placement on the lung transplant waiting list. We used logistic and linear regression models for hypothesis testing. The prevalence of untreated dental disease did not differ by CF status (p = 0.99). There was no difference in waitlist evaluation time for transplant recipients by CF status (p = 0.78) or by dental disease status (p = 0.93).ConclusionsOur findings provide further evidence that individuals with CF are not at low risk for dental disease. Ensuring optimal oral health is important for all individuals with lung diseases.
A Recipe for Madness: Parenthood in the Era of Covid‐19
Authors: Elder Laurel , Greene Steven 
Published: March 2021

ObjectivesThis article seeks to understand the economic, mental health, and political impacts on American parents in the era of Covid‐19.MethodsWe draw on survey data from a diverse national sample collected in September 2020 and employ multivariate analysis to explore how Covid‐19 has uniquely affected the attitudes and life experiences of American parents.ResultsWe find that Covid‐19 has been unusually burdensome for parents as they are more likely to have experienced negative physical and mental health outcomes and suffer more negative financial impacts. Despite the challenges parents face, they also remain cautious about in‐person school and vaccinations. Although mothers have been the focus of much news coverage, we find that both mothers and fathers have been similarly and negatively impacted by Covid‐19.ConclusionAmerican parents are suffering at distinctively high levels during this pandemic. In order to recover, policymakers will need to target outreach and support tailored to the needs and issues facing parents.
Deterrents in recruitment of COVID‐19 convalescent plasma donors: Experience from a hospital‐based blood centre in India
Authors: Dhiman Yashaswi , Coshic Poonam , Pandey Hem Chandra , Khatiwada Basanta , Singh Jasmeet , Mehta Vikas , Gupta Sanjay 
Published: March 2021

AbstractIntroductionRecruitment of Covid‐19 convalescent plasma (CCP) donors may present as a challenge due to inexperience and differences in donor profile as compared to whole blood donation. Present study highlights the deterrents to recruiting CCP donors at a hospital based blood centre.Materials and methodsPotential CCP donors were contacted individually by telephone and a group approach through camp organisers from May to July 2020. Recruitment challenges were noted and deferrals of these recruited donors during screening and medical examination was obtained and analysed.ResultsTotal 1165 potential CCP donors were contacted. Around 47% donors were lost due to challenges related to information storage and retrieval. Fear of health, family pressure, and fear of a new procedure were major reason (27.2%) for unwillingness to donate. The main reasons for deferral among potential donors were multiparity (38%) and being overage/underage (31.6%). Finally, 468 donors were recruited including 408 by individual approach and 60 by a group approach. From these absence of detectable COVID‐19 antibodies were found in 15.4%. Few donors (9.0%) were deferred as they had not completed 28 days post recovery.ConclusionThe process of CCP donor recruitment differs from that of whole blood donation and requires an individualised approach with involvement of clinicians in the initial phases of the pandemic. A group approach targeting specific organisations could be adopted for a successful CCP collection program. There is a need to relook into some aspects of donor selection such as consideration of multiparous female donors and overage/underage donors after reviewing scientific evidence.
Lumbosacral intervertebral disk extrusions in 13 dogs
Authors: Bresciani Luca , Trevail Raquel , Clarke Stephen , Gutierrez‐Quintana Rodrigo , Behr Sebastien , Lazzerini Kali , Brocal Josep , Oxley Bill , Pink Jonathan , José‐López Roberto 
Published: March 2021

AbstractObjectiveTo describe the clinical presentation, magnetic resonance imaging (MRI) findings, and outcome of dogs treated surgically for lumbosacral intervertebral disk extrusion (IVDE).Study DesignRetrospective study.AnimalsThirteen dogs.MethodsRecords and MRI studies of dogs with intraoperatively confirmed lumbosacral IVDE were reviewed. MRI features of thoracolumbar IVDE were applied to all cases. Postoperative outcome was subjectively assessed as excellent, good, or poor.ResultsAll dogs had an acute or subacute onset of lumbosacral pain and nerve root signature. Seven dogs had neurological deficits. MRI revealed lateralized herniated disk material and partial to complete disk degeneration in all cases; the extradural material extended cranial and/or caudally from the disk space in 10 cases. All dogs underwent L7‐S1 dorsal laminectomy and removal of extruded disk material. In six dogs, surgery was complicated by inflammatory changes, including one case of epidural steatitis. On reexamination 4–6 weeks postsurgery, outcome was judged as excellent in 11 dogs and poor in the remaining 2 due to contralateral nerve root signature in one case and nonambulatory paraparesis and urinary incontinence in the case with steatitis.ConclusionLumbosacral IVDE in dogs was characterized by acute/subacute onset of lumbosacral pain and nerve root signature and lateralized and often dispersed extradural material over a degenerated L7‐S1 intervertebral disk on MRI. Early decompressive dorsal laminectomy generally resulted in excellent clinical outcome.Clinical SignificanceObservation of these clinical and imaging features in dogs should prompt clinical suspicion of lumbosacral IVDE.
On the Validation of Turbulence Models for Wheel and Wheelhouse Aerodynamics
Authors: Nabutola Kaloki L. , Boetcher Sandra K. S. 
Published: March 2021

Abstract
Vehicle aerodynamics plays an important role in reducing fuel consumption. The underbody contributes to around 50% of the overall drag of a vehicle. As part of the underbody, the wheels and wheelhouses contribute to approximately 25–30% of the overall drag of a vehicle. As a result, wheel aerodynamics studies have been gaining popularity. However, a consensus of an appropriate turbulence model has not been reached, partially due to the lack of experiments appropriate for turbulence model validation studies for this type of flow. Seven turbulence models were used to simulate the flow within the wheelhouse of a simplified vehicle body, and results were shown to be incongruous with commonly used experimental data. The performance of each model was evaluated by comparing the aerodynamic coefficients obtained using computational fluid dynamics (CFD) to data collected from the Fabijanic wind tunnel experiments. The various turbulence models generally agreed with each other when determining average values, such as mean drag and lift coefficients, even if the particular values did not fall within the uncertainty of the experiment. However, they exhibited differences in the level of resolution in the flow structures within the wheelhouse. These flow structures are not able to be validated with currently available experimental data. Properly resolving flow structures is important when implementing flow-control devices to reduce drag. Results from this study emphasize the need for spatially and time-resolved experiments, especially for validating large eddy simulation (LES) and detached eddy simulation (DES) for flow within a wheelhouse.
Neural Network-Based Transfer Learning of Manipulator Inverse Displacement Analysis
Authors: Tang Houcheng , Notash Leila 
Published: March 2021

Abstract
In this paper, the feasibility of applying transfer learning for modeling robot manipulators is examined. A neural network-based transfer learning approach of inverse displacement analysis of robot manipulators is studied. Neural networks with different structures are applied utilizing data from different configurations of a manipulator for training purposes. Then, the transfer learning was conducted between manipulators with different geometric layouts. The training is performed on both the neural networks with pretrained initial parameters and the neural networks with random initialization. To investigate the rate of convergence of data fitting comprehensively, different values of performance targets are defined. The computing epochs and performance measures are compared. It is presented that, depending on the structure of the neural network, the proposed transfer learning can accelerate the training process and achieve higher accuracy. For different datasets, the transfer learning approach improves their performance differently.
Fault-Tolerant Control of Programmable Logic Controller-Based Production Systems With Deep Reinforcement Learning
Authors: Zinn Jonas , Vogel-Heuser Birgit , Gruber Marius 
Published: March 2021

Abstract
Fault-tolerant control policies that automatically restart programable logic controller-based automated production system during fault recovery can increase system availability. This article provides a proof of concept that such policies can be synthesized with deep reinforcement learning. The authors specifically focus on systems with multiple end-effectors that are actuated in only one or two axes, commonly used for assembly and logistics tasks. Due to the large number of actuators in multi-end-effector systems and the limited possibilities to track workpieces in a single coordinate system, these systems are especially challenging to learn. This article demonstrates that a hierarchical multi-agent deep reinforcement learning approach together with a separate coordinate prediction module per agent can overcome these challenges. The evaluation of the suggested approach on the simulation of a small laboratory demonstrator shows that it is capable of restarting the system and completing open tasks as part of fault recovery.
New zircon radiometric U-Pb ages and Lu-Hf isotopic data from the ultramafic-mafic sequences of Ranau and Telupid (Sabah, eastern Malaysia): Time to reconsider the geological evolution of Southeast Asia?
Authors: Tsikouras Basilios , Lai Chun-Kit , Ifandi Elena , Norazme Nur’Aqidah , Teo Chee-Hui , Xia Xiao-Ping 
Published: March 2021

Abstract
New zircon U-Pb geochronology from a peridotite suite near Ranau and the Telupid ophiolite in Sabah, eastern Malaysia, contradict previous studies, which assumed that the Sabah mafic-ultramafic rocks are largely ophiolitic and Jurassic–Cretaceous in age. We show that these rocks formed during a magmatic episode in the Miocene (9.2–10.5 Ma), which is interpreted to reflect infiltration of melts and melt-rock reaction in the Ranau subcontinental peridotites during extension, and concurrent seafloor spreading forming the Telupid ophiolite further south. Older zircons from the Ranau peridotites have Cretaceous, Devonian, and Neoproterozoic ages. Zircon Lu-Hf isotopic data suggest their derivation from a depleted mantle. However, significant proportions of crustal components have been incorporated in their genesis, as evidenced by their less-radiogenic Hf signature compared to a pristine mantle reservoir. The involvement of a crustal component is consistent with our interpreted continental setting for the Ranau peridotite and formation in a narrow backarc basin for the Telupid ophiolite. We infer that the Sulu Sea, which was expanding throughout much of the Miocene, may have extended to the southwest into central Sabah. The Telupid oceanic strand formed during the split, collapse, and rollback of the Sulu arc due to the subduction of the Celebes Sea beneath Sabah. Incorporation of the Sulu arc in the evolving Miocene oceanic basin is a potential source to explain the involvement of crustal material in the zircon evolution of the Telupid ophiolite.
Symptom cluster is associated with prolonged return-to-play in symptomatic athletes with acute respiratory illness (including COVID-19): a cross-sectional study—AWARE study I
Authors: Schwellnus Martin , Sewry Nicola , Snyders Carolette , Kaulback Kelly , Wood Paola Silvia , Seocharan Ishen , Derman Wayne , Hull James H , Valtonen Maarit , Jordaan Esme 
Published: March 2021

BackgroundThere are no data relating symptoms of an acute respiratory illness (ARI) in general, and COVID-19 specifically, to return to play (RTP).ObjectiveTo determine if ARI symptoms are associated with more prolonged RTP, and if days to RTP and symptoms (number, type, duration and severity) differ in athletes with COVID-19 versus athletes with other ARI.DesignCross-sectional descriptive study.SettingOnline survey.ParticipantsAthletes with confirmed/suspected COVID-19 (ARICOV) (n=45) and athletes with other ARI (ARIOTH) (n=39).MethodsParticipants recorded days to RTP and completed an online survey detailing ARI symptoms (number, type, severity and duration) in three categories:‘nose and throat’,‘chest and neck’ and‘whole body’. We report the association between symptoms and RTP (% chance over 40 days) and compare the days to RTP and symptoms (number, type, duration and severity) in ARICOVversus ARIOTHsubgroups.ResultsThe symptom cluster associated with more prolonged RTP (lower chance over 40 days; %) (univariate analysis) was‘excessive fatigue’ (75%; p<0.0001), ‘chills’ (65%; p=0.004), ‘fever’ (64%; p=0.004), ‘headache’ (56%; p=0.006),‘altered/loss sense of smell’ (51%; p=0.009), ‘Chest pain/pressure’ (48%; p=0.033), ‘difficulty in breathing’ (48%; p=0.022) and ‘loss of appetite’ (47%; p=0.022). ‘Excessive fatigue’ remained associated with prolonged RTP (p=0.0002) in a multiple model. Compared with ARIOTH, the ARICOVsubgroup had more severe disease (greater number, more severe symptoms) and more days to RTP (p=0.0043).ConclusionSymptom clusters may be used by sport and exercise physicians to assist decision making for RTP in athletes with ARI (including COVID-19).
Seroepidemiology of hepatitis A and B in the general population in Hong Kong: protocol of a cross-sectional survey using spatial sampling in a highly urbanised city
Authors: Poon Chin Man , Chan Denise P , Lee Shui Shan , Wong Ngai Sze 
Published: March 2021

IntroductionDifferences in immunisation policies have significantly reshaped the epidemiology of hepatitis A and B in the population. Assessment of the susceptibility and transmission potential of these two types of vaccine-preventable hepatitis would enhance the capacity of public health authorities for viral hepatitis elimination. Focusing on Hong Kong, the objectives of this study comprise the determination of the population-level seroprevalence of hepatitis A and B and an examination of the risk factors for virus transmission and the population impacts of vaccinations.Methods and analysisThis is a cross-sectional household survey on hepatitis A and B. By using socially homogeneous building groups as sampling frame, eligible members of 1327 spatially selected households would be invited to complete a questionnaire and provide blood samples for serological testing (anti-hepatitis A virus, hepatitis B surface antigen, hepatitis B surface and core antibody). The main measures comprise a set of metrics on the prevalence of hepatitis A and B. Analysis would be conducted to examine the association of risk factors with the tested markers and describe the attitudes towards viral hepatitis vaccination.Ethics and disseminationEthical approval from the Joint Chinese University of Hong Kong—New Territories East Cluster Clinical Research Ethics Committee, and approval for laboratory safety from the Chinese University of Hong Kong have been obtained. The study results will be presented in scientific forums to update on the epidemiology of hepatitis A and B and inform the development of new vaccination strategies in Hong Kong.Trial registration numberNCT04371276.
Why women die after reaching the hospital: a qualitative critical incident analysis of the ‘third delay’ in postconflict northern Uganda
Authors: Alobo Gasthony , Ochola Emmanuel , Bayo Pontius , Muhereza Alex , Nahurira Violah , Byamugisha Josaphat 
Published: March 2021

ObjectivesTo critically explore and describe the pathways that women who require emergency obstetrics and newborn care (EmONC) go through and to understand the delays in accessing EmONC after reaching a health facility in a conflict-affected setting.DesignThis was a qualitative study with two units of analysis: (1) critical incident technique (CIT) and (2) key informant interviews with health workers, patients and attendants.SettingThirteen primary healthcare centres, one general private-not-for-profit hospital, one regional referral hospital and one teaching hospital in northern Uganda.ParticipantsForty-nine purposively selected health workers, patients and attendants participated in key informant interviews. CIT mapped the pathways for maternal deaths and near-misses selected based on critical case purposive sampling.ResultsAfter reaching the health facility, a pregnant woman goes through a complex pathway that leads to delays in receiving EmONC. Five reasons were identified for these delays: shortage of medicines and supplies, lack of blood and functionality of operating theatres, gaps in staff coverage, gaps in staff skills, and delays in the interfacility referral system. Shortage of medicines and supplies was central in most of the pathways, characterised by three patterns: delay to treat, back-and-forth movements to buy medicines or supplies, and multiple referrals across facilities. Some women also bypassed facilities they deemed to be non-functional.ConclusionOur findings show that the pathway to EmONC is precarious and takes too long even after making early contact with the health facility. Improvement of skills, better management of the meagre human resource and availing essential medical supplies in health facilities may help to reduce the gaps in a facility’s emergency readiness and thus improve maternal and neonatal outcomes.
Anti-SARS-CoV-2 antibody responses are attenuated in patients with IBD treated with infliximab
Authors: Kennedy Nicholas A , Goodhand James R , Bewshea Claire , Nice Rachel , Chee Desmond , Lin Simeng , Chanchlani Neil , Butterworth Jeffrey , Cooney Rachel , Croft Nicholas M , Hart Ailsa L , Irving Peter M , Kok Klaartje B , Lamb Christopher A , Limdi Jimmy K , Macdonald Jonathan , McGovern Dermot PB , Mehta Shameer J , Murray Charles D , Patel Kamal V , Pollok Richard CG , Raine Timothy , Russell Richard K , Selinger Christian P , Smith Philip J , Bowden Jack , McDonald Timothy J , Lees Charlie W , Sebastian Shaji , Powell Nicholas , Ahmad Tariq 
Published: March 2021

ObjectiveAntitumour necrosis factor (anti-TNF) drugs impair protective immunity following pneumococcal, influenza and viral hepatitis vaccination and increase the risk of serious respiratory infections. We sought to determine whether infliximab-treated patients with IBD have attenuated serological responses to SARS-CoV-2 infections.DesignAntibody responses in participants treated with infliximab were compared with a reference cohort treated with vedolizumab, a gut-selective anti-integrin α4β7 monoclonal antibody that is not associated with impaired vaccine responses or increased susceptibility to systemic infections. 6935 patients were recruited from 92 UK hospitals between 22 September and 23 December 2020.ResultsRates of symptomatic and proven SARS-CoV-2 infection were similar between groups. Seroprevalence was lower in infliximab-treated than vedolizumab-treated patients (3.4% (161/4685) vs 6.0% (134/2250), p<0.0001). Multivariable logistic regression analyses confirmed that infliximab (vs vedolizumab; OR 0.66 (95% CI 0.51 to 0.87), p=0.0027) and immunomodulator use (OR 0.70 (95% CI 0.53 to 0.92), p=0.012) were independently associated with lower seropositivity. In patients with confirmed SARS-CoV-2 infection, seroconversion was observed in fewer infliximab-treated than vedolizumab-treated patients (48% (39/81) vs 83% (30/36), p=0.00044) and the magnitude of anti-SARS-CoV-2 reactivity was lower (median 0.8 cut-off index (0.2–5.6) vs 37.0 (15.2–76.1), p<0.0001).ConclusionsInfliximab is associated with attenuated serological responses to SARS-CoV-2 that were further blunted by immunomodulators used as concomitant therapy. Impaired serological responses to SARS-CoV-2 infection might have important implications for global public health policy and individual anti-TNF-treated patients. Serological testing and virus surveillance should be considered to detect suboptimal vaccine responses, persistent infection and viral evolution to inform public health policy.Trial registration numberISRCTN45176516.