bluuebunny/crossref_metadata_2025_split huggingface dataset:
Run-Time Cutting Force Estimation Based on Learned Nonlinear Frequency Response Function
Authors: Fabro Jacob , Vogl Gregory W. , Qu Yongzhi 
Published: March 2022

Abstract
The frequency response function (FRF) provides an input–output model that describes the system dynamics. Learning the FRF of a mechanical system can facilitate system identification, adaptive control, and condition-based health monitoring. Traditionally, FRFs can be measured by off-line experimental testing, such as impulse response measurements via impact hammer testing. In this paper, we investigate learning FRFs from operational data with a nonlinear regression approach. A regression model with a learned nonlinear basis is proposed for FRF learning for run-time systems under dynamic steady state. Compared with a classic FRF, the data-driven model accounts for both transient and steady-state responses. With a nonlinear function basis, the FRF model naturally handles nonlinear frequency response analysis. The proposed method is tested and validated for dynamic cutting force estimation of machining spindles under various operating conditions. As shown in the results, instead of being a constant linear ratio, the learned FRF can represent different mapping relationships under different spindle speeds and force levels, which accounts for the nonlinear behavior of the systems. It is shown that the proposed method can predict dynamic cutting forces with high accuracy using measured vibration signals. We also demonstrate that the learned data-driven FRF can be easily applied with the few-shot learning scheme to machine tool spindles with different frequency responses when limited training samples are available.
Numerical Investigation of the Fan Flutter Mechanism Related to Acoustic Propagation Characteristics
Authors: Dong Xu , Zhang Yanfeng , Lu Xingen , Zhang Yingjie , Gan Jiuliang 
Published: March 2022

AbstractIn this study, the flutter mechanism related to acoustic propagation characteristics of a wide-chord fan rotor was investigated numerically. The first bending mode and its two and three nodal diameters traveling wave patterns were considered. The unsteady disturbance induced by the blade vibration in the duct gradually changed from cut-off to cut-on mode by increasing the blade frequency. Flutter occurred in some specific frequency range. The upstream cut-on and downstream cut-off condition with the risk of flutter previously identified in other studies was also observed in this paper. A new flutter risk frequency in which the blade frequency was less than the upstream cut-on frequency was found. The results showed that the effects of flow features and acoustic propagation characteristics on aeroelasticity were independent. To explain why flutter was more likely to occur near stall, two sets of frequencies representing different acoustic propagation characteristics were selected to carry out aeroelastic simulations for different working conditions along the same speed line. When flutter occurred, the suction side always provided positive damping, and the pressure side always provided negative damping. This study analyzed the effect of different flow features, such as shock and radial migration, in detail. The phase difference between the pressure fluctuations on the pressure side and the blade velocity played a vital role in fan flutter.
The KPg boundary Chicxulub impact-extinction hypothesis: The winding road towards a solid theory
Authors: Smit J. 
Published: March 2022

ABSTRACT
Along with the origin of life, the quest for the ultimate cause of the end of the dinosaurs and ~72% of other species is one of the most publicized questions in the history of our planet. So, it probably should not have come as a surprise that when Walter Alvarez and his team launched the impact-extinction theory, the opposition and the resistance against the theory was strong from the beginning and continues up to the present day. This paper follows the winding road around the roadblocks that were set up against the theory and how both the opposition against and accumulation of new data, e.g., the finding of the Chicxulub impact structure and extraterrestrial Cr isotope ratios to further develop the theory, went hand in hand. Often the roadblocks were overcome, but new ones were set up, and in the struggle to surmount these, the proponents were forced to look back on their arguments, to carefully re-formulate their viewpoints, and to check whether tunnel-vision had developed that might prevent seeing the data available in a different light. However, looking back on the competition among proponents and opponents 40 years later, the impact-extinction theory is stronger than ever before. It has survived and matured from a hypothesis into a well-established theory, although many questions remain to be solved.
Arc-continent collision during culmination of Proto-Tethyan Ocean closure in the Central Qilian belt, NE Tibetan Plateau
Authors: Yan Zhen , Fu Changlei , Aitchison Jonathan C. , Niu Manlan , Buckman Solomon , Xiao Wenjiao , Zhou Renjie , Chen Lei , Li Junhui 
Published: March 2022

Abstract
Accurate lithostratigraphy framework of the Central Qilian belt is key to understand subduction-collision of the Proto-Tethyan Ocean in the NE Tibetan Plateau. The Dongchagou and the Moshigou formations share similar detrital zircon age populations with youngest age peak at ca. 1.15–1.21 Ga, which is consistent with the granitoid gneiss of the Liujiatai Formation. In combination with rock assemblages, metamorphic facies, and associated oldest granitoid plutons, we revised Precambrian lithostratigraphy of the Central Qilian belt as the &gt;1.2 Ga Huangyuan Group and the ca. 1200–930 Ma Huangzhong Group in this study. The former is the same as the Liujiatai Formation, whereas the later includes the Dongchagou and Moshigou formations. Siliciclastic turbidites of the Qingshipo Formation gradually pass upward into carbonates of the Huashishan Group, we therefore ascribe them to the Huashishan Group. This group unconformably overlies the Precambrian basement of the Central Qilian belt and consists of continental slope to coastal plain deposits with a bi-direction of the S- and N-ward paleocurrent. These sediments contain abundant metamorphic, magmatic, and minor ophiolitic detritus with main age populations of ca. 910 Ma, ca. 487 Ma, and ca. 447 Ma detrital zircons, probably derived from the Central and South Qilian belts. The basement of the Huangzhong Group experienced 440– 430 Ma continent-continent collision-related metamorphism and deformation. These results and regional geology demonstrate that the Huashishan Group was formed by arc-continent collision deposition during culmination of the Proto-Tethyan Ocean closure in the Qilian orogenic belt, NE Tibetan Plateau.
Childhood, teenage and young adult cancer diagnosis during the first wave of the COVID-19 pandemic: a population-based observational cohort study in England
Authors: Saatci Defne , Oke Jason , Harnden Anthony , Hippisley-Cox Julia 
Published: March 2022

ObjectiveTo investigate childhood, teenage and young adult cancer diagnostic pathways during the first wave of the COVID-19 pandemic in England.DesignPopulation-based cohort study.Setting and participantsQResearch, a nationally representative primary care database, linked to hospital admission, mortality and cancer registry data, was used to identify childhood, teenage and young adult cancers (0–24 years) diagnosed between 1 January 2017 and 15 August 2020.Main outcomesMain outcomes of interest were: (1) number of incident cancer diagnoses per month, (2) diagnostic, treatment time intervals and (3) cancer-related intensive care admissions.Results2607 childhood, teenage and young adult cancers were diagnosed from 1 January 2017 to 15 August 2020; 380 were diagnosed during the pandemic period. Overall, 17% (95% CI −28.0% to −4.0%) reduction in the incidence rate ratio of cancers was observed during the pandemic. Specific decreases were seen for central nervous system tumour (−38% (95% CI −52% to −21%)) and lymphoma (−28% (95% CI −45% to −5%)) diagnoses. Additionally, childhood cancers diagnosed during the pandemic were significantly more likely to have intensive care admissions (adjusted OR 2.2 (95% CI 1.33 to 3.47)). Median time-to-diagnosis did not significantly differ across periods (+4.5 days (95% CI −20.5 to +29.5)), while median time-to-treatment was shorter during the pandemic (−0.7 days (95% CI −1.1 to −0.3)).ConclusionsCollectively, our findings of a significant reduction in cancer diagnoses and increase in intensive care admissions provide initial insight into the changes that occurred to childhood, teenage and young adult cancer diagnostic pathways during the first wave of the pandemic.
Paediatric brain MRI findings following congenital heart surgery: a systematic review
Authors: Alablani Fatmah Jamal , Chan Hoi Shan Asia , Beishon Lucy , Patel Nikil , Almudayni Alanoud , Bu'Lock Frances , Chung Emma ML 
Published: March 2022

ObjectiveThis systematic review aimed to establish the relative incidence of new postoperative brain MRI findings following paediatric congenital cardiac surgery.DesignTo distinguish perioperative changes from pre-existing MR findings, our systematic search strategy focused on identifying original research studies reporting both presurgery and postsurgery brain MRI scans. Patient demographics, study methods and brain MR findings were extracted.ResultsTwenty-one eligible publications, including two case-control and one randomised controlled trial, were identified. Pre-existing brain MRI findings were noted in 43% (513/1205) of neonates prior to surgery, mainly white matter injuries (WMI). Surgery was performed at a median age of 8 days with comparison of preoperative and postoperative MR scans revealing additional new postoperative findings in 51% (550/1075) of patients, mainly WMI. Four studies adopted a brain injury scoring system, but the majority did not indicate the severity or time course of findings. In a subgroup analysis, approximately 32% of patients with pre-existing lesions went on to develop additional new lesions postsurgery. Pre-existing findings were not found to confer a higher risk of acquiring brain lesions postoperatively. No evidence was identified linking new MR findings with later neurodevelopmental delay.ConclusionThis systematic review suggests that surgery approximately doubles the number of patients with new brain lesions.
Birth prevalence of anorectal malformations in England and 5-year survival: a national birth cohort study
Authors: Ford Kathryn , Peppa Maria , Zylbersztejn Ania , Curry Joe I , Gilbert Ruth 
Published: March 2022

ObjectiveTo determine the birth prevalence, maternal risk factors and 5-year survival for isolated and complex anorectal malformations.DesignNational birth cohort using hospital admission data and death records.SettingAll National Health Service England hospitals.PatientsLive-born singletons delivered from 2002 through 2018, with evidence in the first year of life of a diagnosis of an anorectal malformation and repair during a hospital admission, or anorectal malformation recorded on the death certificate. Cases were further classified as isolated or complex depending on the presence of additional anomalies.Main outcome measuresBirth prevalence of anorectal malformations per 10 000 live births, risk ratios for isolated and complex anorectal malformation by maternal, infant and birth characteristics, and 5-year survival.ResultsWe identified 3325 infants with anorectal malformations among 9 474 147 live-born singletons; 61.7% (n=2050) of cases were complex. Birth prevalence was 3.5 per 10 000 live births (95% CI 3.4 to 3.6). Complex anorectal malformations were associated with maternal age extremes after accounting for other sociodemographic factors. Compared with maternal ages 25–34 years, the risk of complex anorectal malformations was 31% higher for ≥35 years (95% CI 17 to 48) and 13% higher for ≤24 years (95% CI 0 to 27). Among 2376 anorectal malformation cases (n=1450 complex) born from 2002 through 2014, 5-year survival was lower for complex (86.9%; 95% CI 85.1% to 88.5%) than isolated anorectal malformations (98.2%; 95% CI 97.1% to 98.9%). Preterm infants with complex anorectal malformations had the lowest survival (73.4%; 95% CI 68.1% to 78.0%).ConclusionsDifferences in maternal risk factors for isolated and complex anorectal malformations may reflect different underlying mechanisms for occurrence. Five-year survival is high but lowest for preterm children with complex anorectal malformations.
Predicting 1-year mortality among patients with decompensated cirrhosis: results of a multicentre evaluation of the Bristol Prognostic Score
Authors: Bowers Sarah Pauline , Clare Kathleen , Hagerty Louise , McColl Kirsty , Smith Eva , Brown-Kerr Alana , Ahmed Asma , Finlay Fiona , Dillon John F , Barclay Stephen 
Published: March 2022

ObjectiveChronic liver disease continues to be a significant cause of morbidity and mortality yet remains challenging to prognosticate. This has been one of the barriers to implementing palliative care, particularly at an early stage. The Bristol Prognostic Score (BPS) was developed to identify patients with life expectancy less than 12 months and to act as a trigger for referral to palliative care services. This study retrospectively evaluated the BPS in a cohort of patients admitted to three Scottish hospitals.MethodRoutinely collated healthcare data were used to obtain demographics, BPS and analyse 1-year mortality for patients with decompensated liver disease admitted to three gastroenterology units over two 90-day periods. Statistical analysis was undertaken to assess performance of BPS in predicting mortality.Results276 patients were included in the final analysis. Participants tended to be late middle-aged men, socioeconomically deprived and have alcohol-related liver disease. A similar proportion was BPS+ve (>3) in this study compared with the original Bristol cohort though had more hospital admissions, higher ongoing alcohol use and poorer performance status. BPS performed poorer in this non-Bristol group with sensitivity 54.9% (72.2% in original study), specificity 58% (83.8%) and positive predictive value (PPV) 43.4% (81.3%).ConclusionBPS was unable to accurately predict mortality in this Scottish cohort. This highlights the ongoing challenge of prognostication in patients with chronic liver disease, furthering the call for more work in this field.
Impact of the COVID-19 pandemic on gastrointestinal infection trends in England, February–July 2020
Authors: Love Nicola K , Elliot Alex J , Chalmers Rachel M , Douglas Amy , Gharbia Saheer , McCormick Jacquelyn , Hughes Helen , Morbey Roger , Oliver Isabel , Vivancos Roberto , Smith Gillian 
Published: March 2022

ObjectiveTo establish the impact of the first 6 months of the COVID-19 outbreak response on gastrointestinal (GI) infection trends in England.DesignRetrospective ecological study using routinely collected national and regional surveillance data from seven UK Health Security Agency coordinated laboratory, outbreak and syndromic surveillance systems using key dates of UK governmental policy change to assign phases for comparison between 2020 and historic data.ResultsDecreases in GI illness activity were observed across all surveillance indicators as COVID-19 cases began to peak. Compared with the 5-year average (2015–2019), during the first 6 months of the COVID-19 response, there was a 52% decrease in GI outbreaks reported (1544 vs 3208 (95% CI 2938 to 3478)) and a 34% decrease in laboratory confirmed cases (27 859 vs 42 495 (95% CI 40 068 to 44 922)). GI indicators began to rise during the first lockdown and lockdown easing, although all remained substantially lower than historic figures. Reductions in laboratory confirmed cases were observed across all age groups and both sexes, with geographical heterogeneity observed in diagnosis trends. Health seeking behaviour changed substantially, with attendances decreasing prior to lockdown across all indicators.ConclusionsThere has been a marked change in trends of GI infections in the context of the COVID-19 pandemic. The drivers of this change are likely to be multifactorial; while changes in health seeking behaviour, pressure on diagnostic services and surveillance system ascertainment have undoubtably played a role, there has likely been a true decrease in the incidence for some pathogens resulting from the control measures and restrictions implemented. This suggests that if some of these changes in behaviour such as improved hand hygiene were maintained, then we could potentially see sustained reductions in the burden of GI illness.
Qualitative focus group interview study of communication between patients, dentists and physicians for efficient osteonecrosis of the jaw practices
Authors: Choi Yiseul , Park Heajeong , Hong Namki , Rhee Yumie , Park Wonse 
Published: March 2022

ObjectivesTo investigate problems and the current status of existing methods of communication between patients, dentists and physicians for the prevention and treatment of medication-related osteonecrosis of the jaw (MRONJ).DesignA focus group interview study with a descriptive design using qualitative content analysis of transcripts.SettingSecondary care in Korea.Participants3 patient groups and 4 health professional groups in a total of 32 participants including patients with osteoporosis or bone metastasis, dentists and physicians.ResultsThis study revealed that patients lacked medical knowledge of osteoporosis drugs, whereas dentists and physicians lacked each other’s expertise. All patients reported undergoing dental treatments during the osteoporosis drug treatment, but dentists and physicians had different MRONJ experiences depending on their work setting in primary or secondary care. Patients expressed dissatisfaction with the current system of communication with health professionals via letter as they found this to be a slow process. Dentists and physicians reported the need for effective communication because they felt defensive when sending and receiving medical consults.ConclusionsDespite the low incidence of MRONJ among patients with osteoporosis, it is difficult to treat; thus, it is necessary to inform dentists, physicians and patients about the importance of MRONJ prevention. To this end, close communication among all involved stakeholders about osteoporosis drugs is required.
Effects of depression on employment and social outcomes: a Mendelian randomisation study
Authors: Campbell Desmond , Green Michael James , Davies Neil , Demou Evangelia , Howe Laura D , Harrison Sean , Smith Daniel J , Howard David M , McIntosh Andrew M , Munafò Marcus , Katikireddi Srinivasa Vittal 
Published: March 2022

BackgroundDepression is associated with socioeconomic disadvantage. However, whether and how depression exerts a causal effect on employment remains unclear. We used Mendelian randomisation (MR) to investigate whether depression affects employment and related outcomes in the UK Biobank dataset.MethodsWe selected 227 242 working-age participants (40–64 in men, 40–59 years for women) of white British ethnicity/ancestry with suitable genetic data in the UK Biobank study. We used 30 independent genetic variants associated with depression as instruments. We conducted observational and two-sample MR analyses. Outcomes were employment status (employed vs not, and employed vs sickness/disability, unemployment, retirement or caring for home/family); weekly hours worked (among employed); Townsend Deprivation Index; highest educational attainment; and household income.ResultsPeople who had experienced depression had higher odds of non-employment, sickness/disability, unemployment, caring for home/family and early retirement. Depression was associated with reduced weekly hours worked, lower household income and lower educational attainment, and increased deprivation. MR analyses suggested depression liability caused increased non-employment (OR 1.16, 95% CI 1.06 to 1.26) and sickness/disability (OR 1.56, 95% CI 1.34 to 1.82), but was not causal for caring for home/family, early retirement or unemployment. There was little evidence from MR that depression affected weekly hours worked, educational attainment, household income or deprivation.ConclusionsDepression liability appears to cause increased non-employment, particularly by increasing disability. There was little evidence of depression affecting early retirement, hours worked or household income, but power was low. Effective treatment of depression might have important economic benefits to individuals and society.
Bifurcation occlusions and endovascular treatment outcome in acute ischemic stroke
Authors: Arrarte Terreros Nerea , Bruggeman Agnetha A E , van Voorst Henk , Konduri Praneeta R , Jansen Ivo G H , Kappelhof Manon , Tolhuisen Manon L , Boodt Nikki , Dippel Diederik W J , van der Lugt Aad , van Zwam Wim H , van Oostenbrugge Robert J , van der Worp H. Bart , Emmer Bart J , Meijer Frederick J A , Roos Yvo B W E M , van Bavel Ed , Marquering Henk A , Majoie Charles B L M 
Published: March 2022

BackgroundA thrombus in the M1 segment of the middle cerebral artery (MCA) can occlude this main stem only or extend into the M1-M2 bifurcation. The occlusion pattern may affect endovascular treatment (EVT) success, as a bifurcated thrombus may be more prone to fragmentation during retrieval.ObjectiveTo investigate whether bifurcated thrombus patterns are associated with EVT procedural and clinical outcomes.MethodsOcclusion patterns of MCA thrombi on CT angiography from MR CLEAN Registry patients were classified into three groups: main stem occlusion, bifurcation occlusion extending into one M2 branch, and bifurcation occlusion extending into both M2 branches. Procedural parameters, procedural outcomes (reperfusion grade and embolization to new territory), and clinical outcomes (24-48 hour National Institutes of Health Stroke Scale [NIHSSFU] score, change in NIHSS scores between 24 and 48 hours and baseline ∆[NIHSS], and 90-day modified Rankin Scale [mRS] scores) were compared between occlusion patterns.ResultsWe identified 1023 patients with an MCA occlusion of whom 370 (36%) had a main stem occlusion, 151 (15%) a single branch, and 502 (49%) a double branch bifurcation occlusion. There were no statistically significant differences in retrieval method, procedure time, number of retrieval attempts, reperfusion grade, and embolization to new territory between occlusion patterns. Patients with main stem occlusions had lower NIHSSFUscores than patients with single (7 vs 11, p=0.01) or double branch occlusions (7 vs 9, p=0.04). However, there were no statistically significant differences in ∆NIHSS or in 90-day mRS scores.ConclusionsIn our population, EVT procedural and long-term clinical outcomes were similar for MCA bifurcation occlusions and MCA main stem occlusions.