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Is big team research fair in national research assessments? The case of the UK Research Excellence Framework 2021

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Journal of Data and Information Science 2023年第1期8卷 9-20页

作者： Mike Thelwall Kayvan Kousha Meiko Makita Mahshid Abdoli Emma Stuart Paul Wilson Jonathan Levitt Statistical Cybermetrics and Research Evaluation Group University of WolverhamptonUK

Collaborative research causes problems for research assessments because of the difficulty in fairly crediting its *** splitting the rewards for an article amongst its authors has the greatest surface-level fairness,many important evaluations assign full credit to each author,irrespective of team *** underlying rationales for this are labour reduction and the need to incentivise collaborative work because it is necessary to solve many important societal *** article assesses whether full counting changes results compared to fractional counting in the case of the UK’s Research Excellence Framework(REF)*** this assessment,fractional counting reduces the number of journal articles to as little as 10%of the full counting value,depending on the Unit of Assessment(UoA).Despite this large difference,allocating an overall grade point average(GPA)based on full counting or fractional counting gives results with a median Pearson correlation within UoAs of *** largest changes are for Archaeology(r=0.84)and Physics(r=0.88).There is a weak tendency for higher scoring institutions to lose from fractional counting,with the loss being statistically significant in 5 of the 34 ***,whilst the apparent over-weighting of contributions to collaboratively authored outputs does not seem too problematic from a fairness perspective overall,it may be worth examining in the few UoAs in which it makes the most difference.

关键词： Collaboration Research assessment REF REF2021 Research quality Scientometrics

Investigation of the parameters of spiral pattern in galaxies:the arm width

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Research in Astronomy and Astrophysics 2020年第8期20卷 177-180页

作者： Aleksandr Mosenkov Sergey Savchenko Alexander Marchuk Department for Management of Science and Technology Development Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Applied Sciences Ton Duc Thang UniversityHo Chi Minh CityVietnam Saint Petersburg State University Department of AstrophysicsSt.Petersburg198504 Russia Special Astrophysical Observatory Russian Academy of SciencesNizhnii Arkhyz369167 Russia

In this work,we determine the parameters of spiral structure for a sample of face-on spiral *** practice,the solution to this problem is a hard task because of the diversity of observed characteristics associated with spiral structure,such as the number of arms,their shape,arm contrast,*** study spiral structure in galaxies based on an analysis of photometric cuts perpendicular to the arm *** method is based on an approximation of these slices with an analytical function and derivation of the parameters of spiral structure(arm width,asymmetry,pitch angle)using the fitted parameters from this *** algorithm has been applied to a sample of 155 galaxies selected from the Sloan Digital Sky Survey in different *** this paper,we only consider the results on arm width:most spirals exhibit an increase in their width with galactocentric *** 14 per cent of galaxies in our sample show an opposite trend or have an almost constant arm width at all radii.

关键词： methods:data analysis techniques:photometric galaxies:structure

Viral hepatitis prevalence in patients with active and latent tuberculosis

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World Journal of Gastroenterology 2015年第29期21卷 8920-8926页

作者： Hesam Ahmadi Nooredinvand David W Connell Mahmoud Asgheddi Mohammed Abdullah Marie O'Donoghue Louise Campbell Melissa I Wickremasinghe Ajit Lalvani Onn Min Kon Shahid A Khan Hepatology and Gastroenterology Section Division of Diabetes Endocrinology and MetabolismDepartment of MedicineImperial College London Tuberculosis Service St Mary’s HospitalImperial College Healthcare NHS Trust Liver Unit St Mary’s HospitalImperial College London

AIM: To assess the prevalence of hepatitis B virus(HBV) and hepatitis C virus(HCV) infection and association with drug induced liver injury(DILI) in patients undergoing anti-tuberculosis(TB) ***: Four hundred and twenty nine patients with newly diagnosed TB- either active disease or latent infection- who were due to commence antiTB therapy between September 2008 and May 2011 were included. These patients were prospectively tested for serological markers of HBV, HCV and human immunodeficiency virus(HIV) infections- hepatitis B core antigen(HBc Ag), hepatitis B surface antigen(HBs Ag), hepatitis B e antigen, Ig G and Ig M antibody to HBc Ag(anti-HBc), HCV Ig G antibody and HIV antibody using a combination of enzyme-linked immunosorbent assay, Western blot assay and polymerase chain reaction techniques. Patients were reviewed at least monthly during the TB treatment initiation phase. Liver function tests were measured prior to commencement of antiTB therapy and 2-4 wk later. Liver function tests were also performed at any time the patient had significant nausea, vomiting, rash, or felt non-specifically unwell. Fisher's exact test was used to measure significance in comparisons of proportions between groups. A P value of less than 0.05 was considered statistically ***: Of the 429 patients, 270(62.9%) had active TB disease and 159(37.1%) had latent TB infection. 61(14.2%) patients had isolated anti-HBc positivity, 11(2.6%) were also HBs Ag positive and 7(1.6%) were HCV-antibody positive. 16/270 patients with active TB disease compared to 2/159 patients with latent TB infection had markers of chronic viral hepatitis(HBs Ag or HCV antibody positive; P = 0.023). Similarly the proportion of HBs Ag positive patients were significantly greater in the active vs latent TB infection group(10/43 vs 1/29, P = 0.04). The prevalence of chronic HBV or HCV was significantly higher than the estimated United Kingdom prevalence of 0.3% for each. We found no ass

关键词： Epidemiology Hepatitis B Hepatitis C Tuberculosis Drug induced liver injury

The fundamental plane relation of early-type galaxies:environmental dependence

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Research in Astronomy and Astrophysics 2015年第5期15卷 651-662页

作者： Lei Hou Yu Wang Department of Astronomy University of Science and Technology of China

Using a sample of 70 793 early-type galaxies from SDSS DR7, we study the environmental dependence of the fundamental plane relation. With the help of the galaxy group catalog based on SDSS DR7, we calculate the fundamental planes in different dark matter halo mass bins for both central and satellite galaxies. We find the environmental dependence of the fundamental plane coefficients is similar in the g, r, i and z bands. The environmental dependence for central and satellite galaxies is significantly different. Although the fundamental plane coefficients for centrals vary systematically with the halo mass, those of satellites are similar in different halo mass bins. The discrepancy between centrals and satellites is significant in small halos, but negligible in the largest halo mass bins. These results remain the same when we only keep red galaxies, or galaxies with b/a 〉 0.6, or galaxies in a specific radius range in the sample. After the correction for the sky background, the results are still similar. We suggest that the different environmental effects of the halo mass on centrals and satellites may arise from their different quenching processes.

关键词： galaxies elliptical and lenticular -- galaxies halo -- galaxies statistics

A numerical case study on the long-term seismic assessment of reinforced concrete tunnels in corrosive environments

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第3期15卷 551-572页

作者： Maria Antoniou Antonios Mantakas Nikolaos Nikitas Raul Fuentes ETH Zurich ZurichSwitzerland National Technical University of Athens AthensGreece University of Leeds LeedsUK RWTH Aachen University AachenGermany

The paper investigates the long-term seismic behaviour of an underground reinforced concrete(RC)metro tunnel in Santiago,Chile,considering the combined effects of chloride-induced corrosion and cumulative,low-amplitude seismic shaking on the structure’s *** soil-tunnel response is evaluated with the aid of transient,nonlinear finite element analysis using a two-dimensional(2D)plane strain numerical model that adopts advanced nonlinear models for the simulation of soil and concrete plasticity and the dynamic stiffness *** effects of corrosion deterioration are demonstrated in terms of time-dependent loss of rebar area and cover concrete stiffness and *** study illustrates the influence of ageing and repeated seismic shaking on lining deformation,crack development,and the modal characteristics of the intact and degrading *** results indicate that multiple lowamplitude events drive the non-degrading RC tunnel beyond its elastic regime without significant structural response consequences.A noticeable impact of corrosion deterioration on the structure’s seismic performance is revealed,increasing with the number and intensity of earthquake *** different tunnel embedment depths are comparatively *** analyses demonstrate larger coseismic section convergence in the case of the deeper tunnel,yet a less pronounced effect of ageing and successive seismic loading compared to the shallow section,which is evident in the RC lining cracks at the end of shaking.

关键词： Tunnels Reinforcement corrosion Ageing Earthquakes Numerical modelling Long-term performance Concrete cracking behaviour

Superplastic forming characteristics of AZ41 magnesium alloy

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Transactions of Nonferrous Metals Society of China 2021年第3期31卷 648-654页

作者： S.TAYLOR G.D.WEST E.MOGIRE F.TANG H.R.KOTADIA WMG the University of WarwickCoventry CV47ALUK Buehler WMG Materials Engineering Centrethe University of WarwickCoventry CV47ALUK

An AZ41 magnesium alloy in the hot-rolled condition without further thermomechanical processing to modify its microstructure was investigated to establish its suitability for use within a superplastic forming process and to establish optimum forming *** was assessed using elevated temperature tensile testing and hot gas bulging,across a range of strain rates(1×10^(−1)−1×10^(−3)s^(−1))and temperatures(350−450℃).Circle grid analysis with GOM Aramis cameras was used to understand peak strains and material thinning in relation to industrial forming *** forming EBSD and STEM analysis was conducted to understand the mechanisms responsible for the materials formability,with dynamic recrystallization being clearly *** elongation of 520%was achieved at 450℃ and 1×10^(−3)s^(−1);industrially relevant elongation was achieved at 1×10^(−2) s^(−1) at both 450℃(195%)and 400℃(170%).

关键词： magnesium superplastic forming superplasticity electron back-scattered diffraction(EBSD) AZ41 magnesium alloy

Gastroenterology in developing countries:Issues and advances

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World Journal of Gastroenterology 2009年第23期15卷 2839-2854页

作者： Kate L Mandeville Justus Krabshuis Nimzing Gwamzhi Ladep Chris JJ Mulder Eamonn MM Quigley Shahid A Khan Centre for Infectious Diseases Epidemiology Department of Primary Care and Population Sciences University College London Hampstead Campus Royal Free Hospital London NW3 2PF United Kingdom Highland Data Les Charleix 24390 Tourtoirac Dordogne France Department of Medicine University of Jos and Jos University Teaching Hospital Jos Plateau State P.M.B. 2076 Nigeria Department of Gastroenterology VU University Medical Center Amsterdam 1081 HV Holland World Gastroenterology Organisation and Department of Medicine National University of Ireland Cork University Hospital Clinical Sciences Building Wilton Cork Ireland Department of Hepatology and Gastro-enterology Faculty of Medicine Imperial College London St Mary's Campus London W2 1NY United Kingdom

Developing countries shoulder a considerable burden of gastroenterological disease. Infectious diseases in particular cause enormous morbidity and mortality. Diseases which afflict both western and developing countries are often seen in more florid forms in poorer countries. Innovative techniques continuously improve and update gastroenterological practice. However, advances in diagnosis and treatment which are commonplace in the West, have yet to reach many developing countries. Clinical guidelines, based on these advances and collated in resource-rich environments, lose their relevance outside these settings. In this two-part review, we first highlight the global burden of gastroenterological disease in three major areas： diarrhoeal diseases, hepatitis B, and Helicobacter pylori. Recent progress in their management is explored, with consideration of future solutions. The second part of the review focuses on the delivery of clinical services in developing countries. Inadequate numbers of healthcare workers hamper efforts to combat gastroenterological disease. Reasons for this shortage are examined, along with possibilities for increased specialist training. Endoscopy services, the mainstay of gastroenterology in the West, are in their infancy in many developing countries. The challenges faced by those se^ing up a service are illustrated by the example of a Nigerian endoscopy unit. Finally, we highlight the limited scope of many clinical guidelines produced in western countries. Guidelines which take account of resource limitations in the form of ＂cascades＂ are advocated in order to make these guidelines truly global. Recognition of the different working conditions facing practitioners worldwide is an important step towards narrowing the gap between gastroenterology in rich and poor countries.

关键词： Helicobacter pylori Developing countries Gastrointestinal diseases Health care delivery Practice guidelines

Current and future applications of in vitro magnetic resonance spectroscopy in hepatobiliary disease

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World Journal of Gastroenterology 2006年第30期12卷 4773-4783页

作者： I Jane Cox Amar Sharif Jeremy FL Cobbold Howard C Thomas Simon D Taylor-Robinson Imaging Sciences Department Division of Clinical Sciences Imperial College London Hammersmith Hospital Campus Du Cane Road London W12 OHS United Kingdom Department of Medicine Division of Medi-cine Imperial College London St Mary's Campus London W2 United Kingdom

Nuclear magnetic resonance spectroscopy allows the study of cellular biochemistry and metabolism, both in the whole body in vivo and at higher magnetic field strengths in vitro. Since the technique is non-invasive and non-selective, magnetic resonance spectroscopy methodologies have been widely applied in biochemistry and medicine. In vitro magnetic resonance spectroscopy studies of cells, body fluids and tissues have been used in medical biochemistry to investigate pathophysiologi- cal processes and more recently, the technique has been used by physicians to determine disease abnormalities in vivo. This highlighted topic illustrates the potential of in vitro magnetic resonance spectroscopy in studying the hepatobiliary system. The role of in vitro proton and phosphorus magnetic resonance spectroscopy in the study of malignant and non-malignant liver disease and bile composition studies are discussed, particularly with reference to correlative in vivo whole-body magnetic resonance spectroscopy applications. In summary, magnetic resonance spectroscopy techniques can provide non-invasive biochemical information on disease severity and pointers to underlying pathophysiological processes. Magnetic resonance spectroscopy holds potential promise as a screening tool for disease biomarkers, as well as assessing therapeutic response.

关键词： Magnetic resonance spectroscopy Liver Hepatobiliary disease Membrane metabolism

Discovery of Balmer broad absorption lines in the quasar LBQS 1206+1052

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Research in Astronomy and Astrophysics 2012年第4期12卷 369-382页

作者： Tuo Ji Ting-Gui Wang Hong-Yan Zhou Hui-Yuan Wang Key Laboratory for Research in Galaxies and Cosmology University of Science and Technology of China （USTC） Hefei 230026 China Center for Astrophysics USTC Hefei 230026 China Polar Research Institute of China Shanghai 200136 China

We report the discovery of Balmer broad absorption lines （BALs） in the quasar LBQS 1206＋1052 and present a detailed analysis of the peculiar absorption line spectrum. Besides the Mg II λλ2796, 2803 doublet, BALs are also detected in the He I＊ multiplet at λλ2946, 3189, 3889 A arising from the metastable helium 2 3 S level, and in Hα and Hβ from the excited hydrogen H I＊ n = 2 level, which are rarely seen in quasar spectra. We identify two components in the BAL troughs of v ～ 2000 km s 1 width： One component shows an identical profile in H I＊, He I＊ and Mg II with its centroid blueshifted by v c ≈ 726 km s-1 . The other component is detected in He I＊ and Mg II with v c ≈ 1412 km s-1 . We estimate the column densities of H I＊, He I＊, and Mg II, and compare them with possible level population mechanisms. Our results favor the scenario that the Balmer BALs originate in a partially ionized region with a column density of N H ～ 10 21 10 22 cm-2 for an electron density of n e ～ 10 6 10 8 cm-3 via Lyα resonant scattering pumping. The harsh conditions needed may help to explain the rarity of Balmer absorption line systems in quasar spectra. With an i-band PSF magnitude of 16.50, LBQS 1206＋1052 is the brightest Balmer-BAL quasar ever reported. Its high brightness and unique spectral properties make LBQS 1206＋1052 a promising candidate for followup high-resolution spectroscopy, multi-band observations, and long-term monitoring.

关键词： galaxies active -- quasar absorption lines -- quasar individual (LBQS1206+1052)