39 results on '"Paul, Nichols"'
Search Results
2. Acute Mountain Sickness Following Incremental Trekking to High Altitude: Correlation With Plasma Vascular Endothelial Growth Factor Levels and the Possible Effects of Dexamethasone and Acclimatization Following Re-exposure
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Craig Winter, Tracy Bjorkman, Stephanie Miller, Paul Nichols, John Cardinal, Peter O’Rourke, Emma Ballard, Fatima Nasrallah, and Viktor Vegh
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VEGF ,dexamethasone ,acute mountain sickness ,blood-brain barrier ,acclimatization ,Physiology ,QP1-981 - Abstract
Purpose: The recognition and treatment of high-altitude illness (HAI) is increasingly important in global emergency medicine. High altitude related hypobaric hypoxia can lead to acute mountain sickness (AMS), which may relate to increased expression of vascular endothelial growth factor (VEGF), and subsequent blood-brain barrier (BBB) compromise. This study aimed to establish the relationship between AMS and changes in plasma VEGF levels during a high-altitude ascent. VEGF level changes with dexamethasone, a commonly used AMS medication, may provide additional insight into AMS.Methods: Twelve healthy volunteers ascended Mt Fuji (3,700 m) and blood samples were obtained at distinct altitudes for VEGF analysis. Oxygen saturation (SPO2) measurements were also documented at the same time-point. Six out of the 12 study participants were prescribed dexamethasone for a second ascent performed 48 h later, and blood was again collected to establish VEGF levels.Results: Four key VEGF observations could be made based on the data collected: (i) the baseline VEGF levels between the two ascents trended upwards; (ii) those deemed to have AMS in the first ascent had increased VEGF levels (23.8–30.3 pg/ml), which decreased otherwise (23.8–30.3 pg/ml); (iii) first ascent AMS participants had higher VEGF level variability for the second ascent, and similar to those not treated with dexamethasone; and (iv) for the second ascent dexamethasone participants had similar VEGF levels to non-AMS first ascent participants, and the variability was lower than for first ascent AMS and non-dexamethasone participants. SPO2 changes were unremarkable, other than reducing by around 5% irrespective of whether measurement was taken for the first or second ascent.Conclusion: First ascent findings suggest a hallmark of AMS could be elevated VEGF levels. The lack of an exercise-induced VEGF level change strengthened the notion that elevated plasma VEGF was brain-derived, and related to AMS.
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- 2021
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3. Blood-brain barrier dysfunction significantly correlates with serum matrix metalloproteinase-7 (MMP-7) following traumatic brain injury
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Paul Nichols, Javier Urriola, Stephanie Miller, Tracey Bjorkman, Kate Mahady, Viktor Vegh, Fatima Nasrallah, and Craig Winter
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Traumatic brain injury ,Blood brain barrier ,Matrix metalloproteinase ,Dynamic contrast enhanced magnetic resonance imaging ,KTrans ,Computer applications to medicine. Medical informatics ,R858-859.7 ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Objectives: To determine if radiological evidence of blood brain barrier (BBB) dysfunction, measured using Dynamic Contrast Enhanced MRI (DCE-MRI), correlates with serum matrix metalloproteinase (MMP) levels in traumatic brain injury (TBI) patients, and thereby, identify a potential biomarker for BBB dysfunction. Patients and Methods: 20 patients with a mild, moderate, or severe TBI underwent a DCE-MRI scan and BBB dysfunction was interpreted from KTrans. KTrans is a measure of capillary permeability that reflects the efflux of gadolinium contrast into the extra-cellar space. The serum samples were concurrently collected and later analysed for MMP-1, −2, −7, −9, and −10 levels using an ELISA assay. Statistical correlations between MMP levels and the KTrans value were calculated. Multiple testing was corrected using the Benjamin–Hochberg method to control the false‐discovery rate (FDR). Results: Serum MMP-1 values ranged from 1.5 to 49.6 ng/ml (12 ± 12.7), MMP-2 values from 58.3 to 174.1 ng/ml (109.5 ± 26.7), MMP-7 from 1.5 to 31.5 ng/mL (10 ± 7.4), MMP-9 from 128.6 to 1917.5 ng/ml (647.7 ± 749.6) and MMP-10 from 0.1 to 0.6 ng/mL (0.3 ± 0.2). Non-parametric Spearman correlation analysis on the data showed significant positive relationship between KTrans and MMP-7 (r = 0.55, p
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- 2021
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4. Diagnostic accuracy of whole-body MRI versus standard imaging pathways for metastatic disease in newly diagnosed colorectal cancer: the prospective Streamline C trial
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Vicky Goh, Alistair Rienhardt, Priya Limbu, Veronica A. Morgan, Beth Shepherd, David J. Breen, Kayleigh Gilbert, Paul Nichols, Lisa Woodrow, Neal Navani, Sophia Hans, Stephen Karp, Ruth E.C. Evans, Chris Everitt, Andrew Gogbashian, Elizabeth Chang, Nina Tunariu, Amelia Daniel, Elizabeth Hadley, Tina Mills-Baldock, Clare Collins, Ibiyemi Olaleye, Shraddha Weir, Martha Handousa, Rob Glynne-Jones, Steve Halligan, Antony Higginson, Uday Patel, Azmina Verjee, Aji Kavidasan, Sarah Howling, Andrew Bateman, Priscilla Phiri, Imogen Locke, Lyn Blakeway, Joanne Kellaway, Abel Jalloh, Elizabeth Green, Helen Pardoe, Simon Ball, Reyes Lauigan, Jonathan Wilson, Dominic Blunt, U. Ekeowa, Amy Davis, Jon Robinson, S. Burke, Prital Patel, Marian Duggan, Harbir S. Sidhu, Farzana Rahman, Sofia Gourtsoyianni, Shaki Balogun, Pippa Riddle, Peter Boavida, Colin Elton, Stefania Stegner, Daniel J. Smith, Zoltan Nagy, Suzanne Chukundah, Jenna Couture, Laura L. Quinn, Terry O'Shaughnessy, Revanth Jannapureddy, Heather Hughes, Shonit Punwani, Subramanian Ramesh, Anne Miles, Sajid A. Khan, Michelle Saull, Stuart A. Taylor, Tanjil Nawaz, Khawaja Shahabuddin, Andy Lowe, Gauraang Bhatnagar, James Crosbie, Thida Win, Rashidat Adeniba, Helen Beedham, Sahar Naaseri, Nicola Lucas, Fiona McKirdy, Abby Sharp, Lorraine Hurl, Nicola Gibbons, Laura Hughes, Alison Morton, William Partridge, Amy Smith, Krystyna Reczko, Rudi Borgstein, Ann O'Callaghan, Davide Prezzi, Ayshea Hameeduddin, Nelesh Jeyadevan, Matthew Train, John O'Donohue, Teresa Light, Shahanara Ferdous, Austen Obichere, Caroline S. Clarke, Wivijin Piga, Anita Rhodes, Ian C Simcock, Meena Reddi, Shanna Wilson, John Bridgewater, Keyury Desai, Anwar R. Padhani, Maureen Furneaux, Raj Srirajaskanthan, Kishor Barhate, Anita Amadi, Sandy Beare, Dorothee Boisfer, Ferrial Syeed, Elizabeth Isaac, Amjad Mohammed, Katie Prior, Mohamed A. Thaha, Jonathan McCullogh, Kara Sargus, Andrea Rockall, Clive Kay, David Chao, Eleni Ntala, J. James Stirling, Dow-Mu Koh, David Birch, Adrian Green, Marie Jackson, Sanjaya Wijeyekoon, Girija Anand, Hameed Rafiee, Ali Mohammed, Richard Beable, William Ricketts, Liane Davis, Shafi Ahmed, Tina Stoycheva, Sally O'Connor, Jamila Roehrig, Steve Ellis, Catherine Norman, Balinder Hans, Nishat Bharwani, Peter Russell, Kitrick Perry, Ellice Marwood, Alfred Oliver, Stephen Morris, Veronica Conteh, Eleni Karapanagiotou, Saba Mahmud, Sidra Tulmuntaha, Christian Kelly-Morland, Alice Johnson, Sasithar Maheswaran, Farid Bazari, Yvonne Campbell, Rajapandian Ilangovan, Adnam Alam, Tuck-Kay Loke, Susan Mallett, G. Atkin, Nicola H. Strickland, Dominic Yu, Ashley M. Groves, Chloe van Someren, Ian Jenkins, Kai-Keen Shiu, Colm Prendergast, Sherif Raouf, Jagadish Kalasthry, David Snell, Nathalie Rich, Louise Lim, Michael Long, Edward W. Johnston, Kathryn Tarver, Sam M. Janes, Laletha Agoramoorthy, Rommel Butawan, Pooja Datt, Jonathan Teague, Christopher Wanstall, Jane De Los, Sara Lock, Adoracion Jayme, Alec Engledow, Janet McGowan, Andre Nunes, Akosa Aboagye, Howard Curtis, Teresita Beeston, Angshu Bhowmik, Gule Hanid, E. Scurr, Payal Julka, Lesley Honeyfield, Aileen Austria, Celia Simeon, Katherine van Ree, Adesewa Onajobi, Lara Curry, Imperial College Healthcare NHS Trust- BRC Funding, and Department of Health
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Male ,medicine.medical_specialty ,Technology Assessment, Biomedical ,Colorectal cancer ,Population ,Streamline investigators ,Sensitivity and Specificity ,Article ,law.invention ,Metastasis ,psyc ,03 medical and health sciences ,0302 clinical medicine ,Randomized controlled trial ,law ,Internal medicine ,medicine ,Humans ,Whole Body Imaging ,Prospective Studies ,Neoplasm Metastasis ,Adverse effect ,education ,Prospective cohort study ,Aged ,Neoplasm Staging ,education.field_of_study ,Pregnancy ,Hepatology ,business.industry ,Gastroenterology ,Cancer ,Neoplasms, Second Primary ,Middle Aged ,Reference Standards ,medicine.disease ,Magnetic Resonance Imaging ,3. Good health ,030220 oncology & carcinogenesis ,Critical Pathways ,Female ,030211 gastroenterology & hepatology ,Colorectal Neoplasms ,business - Abstract
BACKGROUND: Whole-body MRI (WB-MRI) could be an alternative to multimodality staging of colorectal cancer, but its diagnostic accuracy, effect on staging times, number of tests needed, cost, and effect on treatment decisions are unknown. We aimed to prospectively compare the diagnostic accuracy and efficiency of WB-MRI-based staging pathways with standard pathways in colorectal cancer.METHODS: The Streamline C trial was a prospective, multicentre trial done in 16 hospitals in England. Eligible patients were 18 years or older, with newly diagnosed colorectal cancer. Exclusion criteria were severe systemic disease, pregnancy, contraindications to MRI, or polyp cancer. Patients underwent WB-MRI, the result of which was withheld until standard staging investigations were complete and the first treatment decision made. The multidisciplinary team recorded its treatment decision based on standard investigations, then on the WB-MRI staging pathway (WB-MRI plus additional tests generated), and finally on all tests. The primary outcome was difference in per-patient sensitivity for metastases between standard and WB-MRI staging pathways against a consensus reference standard at 12 months, in the per-protocol population. Secondary outcomes were difference in per-patient specificity for metastatic disease detection between standard and WB-MRI staging pathways, differences in treatment decisions, staging efficiency (time taken, test number, and costs), and per-organ sensitivity and specificity for metastases and per-patient agreement for local T and N stage. This trial is registered with the International Standard Randomised Controlled Trial registry, number ISRCTN43958015, and is complete.FINDINGS: Between March 26, 2013, and Aug 19, 2016, 1020 patients were screened for eligibility. 370 patients were recruited, 299 of whom completed the trial; 68 (23%) had metastasis at baseline. Pathway sensitivity was 67% (95% CI 56 to 78) for WB-MRI and 63% (51 to 74) for standard pathways, a difference in sensitivity of 4% (-5 to 13, p=0·51). No adverse events related to imaging were reported. Specificity did not differ between WB-MRI (95% [95% CI 92-97]) and standard pathways (93% [90-96], p=0·48). Agreement with the multidisciplinary team's final treatment decision was 96% for WB-MRI and 95% for the standard pathway. Time to complete staging was shorter for WB-MRI (median, 8 days [IQR 6-9]) than for the standard pathway (13 days [11-15]); a 5-day (3-7) difference. WB-MRI required fewer tests (median, one [95% CI 1 to 1]) than did standard pathways (two [2 to 2]), a difference of one (1 to 1). Mean per-patient staging costs were £216 (95% CI 211-221) for WB-MRI and £285 (260-310) for standard pathways.INTERPRETATION: WB-MRI staging pathways have similar accuracy to standard pathways and reduce the number of tests needed, staging time, and cost.FUNDING: UK National Institute for Health Research.
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- 2019
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5. Statistical and Lifetime Characterization of PTFE Materials for Extreme Environments
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Dominic Devito, Ali P. Gordon, Sannmit Shinde, Meghan Kenny, Ming-Hang Yang, Jim Drago, Paul Nichols, and Zachary Poust
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Stress (mechanics) ,Compressive strength ,Materials science ,Gasket ,Deformation (meteorology) ,Composite material ,Leakage (electronics) ,Characterization (materials science) - Abstract
Most industrial manufacturing or process plants use bolted connections to transfer media from one location to another. Gaskets are often used to seal these systems as they offer high levels of leak mitigation; however, despite their nearly universal usage, testing done on gaskets has been limited. Historically, while industrial applications use gaskets at various temperatures and pressures, load retention tests have been conducted at a set temperature, time duration and compressive stress and report the result as load lost or retained. They do not account for longer time periods, the characteristics of the load loss over time or internal pressure the gasket is sealing. This current study seeks to change that. Traditional flat gaskets at thicknesses of 1/16” and 1/8” are leveraged against novel textured PTFE gaskets to compare load retention behavior across a range of styles. Different filler materials are tested as well, from aluminosilicate microspheres to barium sulfate and silica. Some design of experiments (DOE) methods are applied to characterize the factors that are most responsible for the load relaxation response of any particular type of gasket. A parameter from a previous study, efficiency, is used as an overall metric to quantify gasket performance. Furthermore, overall gasket deformation is examined to validate the statistical findings. Lastly, an empirical equation is presented that may be able to characterize gasket behavior across multiple loading and environmental conditions, as well as estimate the residual load carrying capacity of a gasket.
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- 2021
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6. Blood-brain barrier dysfunction significantly correlates with serum matrix metalloproteinase-7 (MMP-7) following traumatic brain injury
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Stephanie M. Miller, Viktor Vegh, Craig Winter, Fatima A. Nasrallah, Javier Urriola, Paul Nichols, Tracey Bjorkman, and Kate Mahady
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medicine.medical_specialty ,KTrans ,Traumatic brain injury ,Cognitive Neuroscience ,Computer applications to medicine. Medical informatics ,Urology ,R858-859.7 ,Vascular permeability ,Matrix metalloproteinase ,Blood–brain barrier ,050105 experimental psychology ,03 medical and health sciences ,0302 clinical medicine ,Brain Injuries, Traumatic ,Medicine ,Humans ,0501 psychology and cognitive sciences ,Radiology, Nuclear Medicine and imaging ,RC346-429 ,business.industry ,05 social sciences ,Regular Article ,Elisa assay ,medicine.disease ,Magnetic Resonance Imaging ,Peripheral ,medicine.anatomical_structure ,Neurology ,Matrix Metalloproteinase 9 ,Blood brain barrier ,Blood-Brain Barrier ,Matrix Metalloproteinase 7 ,Dynamic contrast-enhanced MRI ,Biomarker (medicine) ,Neurology (clinical) ,Neurology. Diseases of the nervous system ,Dynamic contrast enhanced magnetic resonance imaging ,business ,030217 neurology & neurosurgery - Abstract
Highlights • Matrix metalloproteinase (MMP) 7 is elevated in traumatic brain injury. • Blood brain barrier dysfunction as measured by DCE MRI can be expressed as KTrans. • MMP-7 shows a strong correlation with BBB dysfunction shown on MRI. • MMP-7 shows potential to function as a serum biomarker., Objectives To determine if radiological evidence of blood brain barrier (BBB) dysfunction, measured using Dynamic Contrast Enhanced MRI (DCE-MRI), correlates with serum matrix metalloproteinase (MMP) levels in traumatic brain injury (TBI) patients, and thereby, identify a potential biomarker for BBB dysfunction. Patients and Methods 20 patients with a mild, moderate, or severe TBI underwent a DCE-MRI scan and BBB dysfunction was interpreted from KTrans. KTrans is a measure of capillary permeability that reflects the efflux of gadolinium contrast into the extra-cellar space. The serum samples were concurrently collected and later analysed for MMP-1, −2, −7, −9, and −10 levels using an ELISA assay. Statistical correlations between MMP levels and the KTrans value were calculated. Multiple testing was corrected using the Benjamin–Hochberg method to control the false‐discovery rate (FDR). Results Serum MMP-1 values ranged from 1.5 to 49.6 ng/ml (12 ± 12.7), MMP-2 values from 58.3 to 174.1 ng/ml (109.5 ± 26.7), MMP-7 from 1.5 to 31.5 ng/mL (10 ± 7.4), MMP-9 from 128.6 to 1917.5 ng/ml (647.7 ± 749.6) and MMP-10 from 0.1 to 0.6 ng/mL (0.3 ± 0.2). Non-parametric Spearman correlation analysis on the data showed significant positive relationship between KTrans and MMP-7 (r = 0.55, p
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- 2021
7. Emergency Intraoperative Ultrasound for the Neurosurgical Trainee
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Jonathan Hempenstall, Phoebe Brandis, Harry Bulstrode, Damian Amato, Samuel Hall, Paul Nichols, and Andrew Durnford
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medicine.medical_specialty ,business.industry ,Ultrasound ,Neurosurgery ,Training Support ,medicine.disease ,Neurosurgical Procedures ,Intraoperative ultrasound ,Hydrocephalus ,Shunt (medical) ,Neuroradiography ,medicine ,Humans ,Surgery ,Neurology (clinical) ,Radiology ,business ,External ventricular drain ,Neuroradiology ,Ultrasonography - Abstract
The use of intraoperative ultrasound in emergency cranial neurosurgical procedures is not well described. It may improve surgical outcomes and is useful when other neuro-navigation systems are not readily available. We provide a practical guide for neurosurgical trainees to utilize ultrasound for various emergency cranial neurosurgical procedures, including lesion localization, insertion of an external ventricular drain, and shunt revision surgery. Intraoperative ultrasound is a useful modality for urgent neurosurgical procedures.
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- 2021
8. Climate warming alters the structure of farmland tritrophic ecological networks and reduces crop yield
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Stephane A. P. Derocles, Sophie C. F. Berthe, Paul Nichols, Darren M. Evans, Ellen D. Moss, David H. Lunt, Agroécologie [Dijon], Université de Bourgogne (UB)-Institut National de la Recherche Agronomique (INRA)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement, University of Hull, Newcastle University [Newcastle], School of Natural and Environmental Sciences, Newcastle University, and Higher Education Innovation Fund
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Crops, Agricultural ,0106 biological sciences ,0301 basic medicine ,Farms ,Climate Change ,[SDV]Life Sciences [q-bio] ,Wasps ,Climate change ,Growing season ,Biology ,global warming ,010603 evolutionary biology ,01 natural sciences ,Crop ,03 medical and health sciences ,Genetics ,Animals ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,DNA barcoding ,Herbivory ,Ecosystem ,Triticum ,Ecology, Evolution, Behavior and Systematics ,Trophic level ,Phenology ,Crop yield ,fungi ,Global warming ,Temperature ,food and beverages ,food security ,030104 developmental biology ,Agronomy ,Aphids ,food webs ,[SDE]Environmental Sciences ,Species richness ,ecosystem services ,natural pest control - Abstract
It is unclear how sustained increases in temperature and changes in precipitation, as a result of climate change, will affect crops and their interactions with agricultural weeds, insect pests and predators, due to the difficulties in quantifying changes in such complex relationships. We simulated the combined effects of increasing temperature (by an average of 1.4 degrees C over a growing season) and applying additional rainwater (10% of the monthly mean added weekly, 40% total) using a replicated, randomized block experiment within a wheat crop. We examined how this affected the structure of 24 quantitative replicate plant-aphid-parasitoid networks constructed using DNA-based methods. Simulated climate warming affected species richness, significantly altered consumer-resource asymmetries and reduced network complexity. Increased temperature induced an aphid outbreak, but the parasitism rates of aphids by parasitoid wasps remained unchanged. It also drove changes in the crop, altering in particular the phenology of the wheat as well as its quality (i.e., fewer, lighter seeds). We discuss the importance of considering the wider impacts of climate change on interacting species across trophic levels in agroecosystems.
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- 2018
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9. Electrical fluctuations and photoinduced current transients in Cd(sub x)Hg(sub 1-x)Te long wavelength epilayers
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Paul, Nichols, Van Vliet, Carolyne M., and Mergui, Sylvia
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Cadmium -- Research ,Semiconductors -- Research ,Infrared detectors -- Research ,Physics - Abstract
Measurements were obtained for the current-voltage characteristics, resistance vs inverse temperature, noise spectra and photoresponse for frequencies of 10 Hz to 1 MHz in the temperature range 300-50 K for cadmium-mercury telluride long-wavelength infrared detectors with 12micro epitaxial layers on wide band gap material. The noise was composed of 1/f noise and one or two Lorentzians, due to shallow hole traps, probably related to mercury vacancies.
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- 1999
10. Preliminary Material Evaluation of Flax Fibers for Prosthetic Socket Fabrication
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Patrick Dumond, Paul Nichols, Inès Chikhaoui, Edward D. Lemaire, and Dominic Monette
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0106 biological sciences ,030506 rehabilitation ,Materials science ,Modal analysis ,Composite number ,Biomedical Engineering ,Artificial Limbs ,01 natural sciences ,Load cell ,law.invention ,Vibration ,03 medical and health sciences ,Synthetic fiber ,Flexural strength ,law ,010608 biotechnology ,Physiology (medical) ,Bending stiffness ,Materials Testing ,Hammer ,Glass ,Composite material ,0305 other medical science - Abstract
Composite prosthetic sockets are typically made of fiberglass or carbon fiber. These fibers have good mechanical properties, but relatively poor vibration damping. Flax fibers are claimed to have exceptional vibration damping properties, with the added benefit of being a natural renewable resource and a cost-effective alternative to synthetic fibers. Flax fibers could prove beneficial for prosthetic sockets, providing lightweight sockets that reduce vibrations transmitted to the body during movement. This research used impact testing (impulse hammer and custom drop tower) on flat and socket shaped composite samples to evaluate composite layer options. Sample vibration dissipation was measured by a combination of accelerometers, load cells, and a dynamometer. Composite sockets made purely of flax fibers were lighter and more efficient at damping vibrations, reducing the amplification of vibrations by a factor of nearly four times better than sockets made purely of carbon fiber. However, the bending stiffness, elastic moduli, and flexural strength of flax sockets fabricated using the traditional socket manufacturing method were found to be ten times lower than theoretical values of flax composites found in the literature. By increasing fiber volume fraction when using the traditional socket manufacturing method, the composite's mechanical properties, namely, vibration damping, could improve and flax fiber benefits could be explored further.
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- 2020
11. Environmental DNA metabarcoding of lake fish communities reflects long-term data from established survey methods
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Lori Lawson Handley, Rosetta C. Blackman, Bernd Hänfling, Jianlong Li, Christoph Hahn, Daniel S. Read, Paul Nichols, Anna Oliver, and Ian J. Winfield
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0106 biological sciences ,0301 basic medicine ,Biodiversity ,Biology ,010603 evolutionary biology ,01 natural sciences ,Ecology and Environment ,03 medical and health sciences ,Survey methodology ,Abundance (ecology) ,Genetics ,Animals ,DNA Barcoding, Taxonomic ,Environmental DNA ,Transect ,Ecology, Evolution, Behavior and Systematics ,Ecology ,Fishes ,DNA ,Cytochromes b ,United Kingdom ,Lakes ,Biology and Microbiology ,030104 developmental biology ,Long term data ,%22">Fish ,Rank abundance curve ,Environmental Monitoring - Abstract
Organisms continuously release DNA into their environments via shed cells, excreta, gametes and decaying material. Analysis of this 'environmental DNA' (eDNA) is revolutionizing biodiversity monitoring. eDNA outperforms many established survey methods for targeted detection of single species, but few studies have investigated how well eDNA reflects whole communities of organisms in natural environments. We investigated whether eDNA can recover accurate qualitative and quantitative information about fish communities in large lakes, by comparison to the most comprehensive long-term gill-net data set available in the UK. Seventy-eight 2L water samples were collected along depth profile transects, gill-net sites and from the shoreline in three large, deep lakes (Windermere, Bassenthwaite Lake and Derwent Water) in the English Lake District. Water samples were assayed by eDNA metabarcoding of the mitochondrial 12S and cytochrome b regions. Fourteen of the 16 species historically recorded in Windermere were detected using eDNA, compared to four species in the most recent gill-net survey, demonstrating eDNA is extremely sensitive for detecting species. A key question for biodiversity monitoring is whether eDNA can accurately estimate abundance. To test this, we used the number of sequence reads per species and the proportion of sampling sites in which a species was detected with eDNA (i.e. site occupancy) as proxies for abundance. eDNA abundance data consistently correlated with rank abundance estimates from established surveys. These results demonstrate that eDNA metabarcoding can describe fish communities in large lakes, both qualitatively and quantitatively, and has great potential as a complementary tool to established monitoring methods.
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- 2016
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12. Diagnostic accuracy of whole-body MRI versus standard imaging pathways for metastatic disease in newly diagnosed non-small-cell lung cancer: the prospective Streamline L trial
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Helen Pardoe, Teresa Light, Sherif Raouf, Lara Curry, Alison Morton, Keyury Desai, Colin Elton, Anita Rhodes, Anita Amadi, Shraddha Weir, Tanjil Nawaz, David Chao, Ian C Simcock, U. Ekeowa, Louise Lim, S. Burke, Peter Boavida, Subramanian Ramesh, Reyes Lauigan, Prital Patel, Ann O'Callaghan, Ayshea Hameeduddin, John O'Donohue, Marie Jackson, Anwar R. Padhani, Hameed Rafiee, Ferrial Syeed, Amjad Mohammed, Sally O'Connor, Simon Ball, Elizabeth Isaac, Elizabeth Chang, Nina Tunariu, Jon Robinson, Pippa Riddle, Martha Handousa, Jonathan Wilson, Thida Win, Rashidat Adeniba, Rob Glynne-Jones, Steve Halligan, Aji Kavidasan, Kara Sargus, Amelia Daniel, Amy Smith, Adnam Alam, Tuck-Kay Loke, Amy Davis, Harbir S. Sidhu, Shahanara Ferdous, Sarah Howling, Michael Long, Gauraang Bhatnagar, Antony Higginson, Uday Patel, Pooja Datt, Christopher Wanstall, Terry O'Shaughnessy, Susan Mallett, Ashley M. Groves, Tina Mills-Baldock, James Crosbie, Shonit Punwani, Sam M. Janes, Aileen Austria, Anne Miles, Michelle Saull, Shanna Wilson, Raj Srirajaskanthan, Ibiyemi Olaleye, Kayleigh Gilbert, Heather Hughes, Fiona McKirdy, Adrian Green, Vicky Goh, Chloe van Someren, Kishor Barhate, Sandy Beare, Shaki Balogun, Adoracion Jayme, Khawaja Shahabuddin, Sajid A. Khan, Matthew Train, Austen Obichere, Azmina Verjee, Wivijin Piga, Janet McGowan, Sanjaya Wijeyekoon, E. Scurr, Jonathan McCullogh, Andrea Rockall, David J. Breen, Andy Lowe, Nicola Lucas, Alistair Rienhardt, Dow-Mu Koh, Lesley Honeyfield, John Bridgewater, Edward W. Johnston, Meena Reddi, Eleni Ntala, Colm Prendergast, Priya Limbu, Veronica A. Morgan, Laletha Agoramoorthy, William Partridge, Maureen Furneaux, Helen Beedham, Abby Sharp, Balinder Hans, Katie Prior, David Birch, Mohamed A. Thaha, Dorothee Boisfer, Clive Kay, Jagadish Kalasthry, Rudi Borgstein, Adesewa Onajobi, David Snell, Stuart A. Taylor, Nicola Gibbons, Christian Kelly-Morland, Sasithar Maheswaran, Angshu Bhowmik, Jane De Los, Ali Mohammed, Richard Beable, Tina Stoycheva, Paul Nichols, Beth Shepherd, Alec Engledow, Laura Hughes, Lyn Blakeway, Gule Hanid, Lisa Woodrow, Andre Nunes, Neal Navani, Sophia Hans, Stephen Karp, Nishat Bharwani, Kitrick Perry, Kathryn Tarver, Howard Curtis, Sahar Naaseri, Ian Jenkins, Teresita Beeston, J. James Stirling, Krystyna Reczko, Chris Everitt, Rommel Butawan, Stephen Morris, Eleni Karapanagiotou, Jonathan Teague, Priscilla Phiri, Andrew Gogbashian, Imogen Locke, Payal Julka, Sara Lock, Caroline S. Clarke, Yvonne Campbell, Rajapandian Ilangovan, Akosa Aboagye, Celia Simeon, William Ricketts, Marian Duggan, Ellice Marwood, Lorraine Hurl, Katherine van Ree, Daniel J. Smith, Elizabeth Hadley, Kai-Keen Shiu, Saba Mahmud, Clare Collins, David Prezzi, Revanth Jannapureddy, Andrew Bateman, Steve Ellis, Peter Russell, Veronica Conteh, Abel Jalloh, Elizabeth Green, Sidra Tulmuntaha, Dominic Blunt, Sofia Gourtsoyianni, Alice Johnson, Stefania Stegner, Alfred Oliver, Nathalie Rich, Joanne Kellaway, Farzana Rahman, Zoltan Nagy, Suzanne Chukundah, Ruth E.C. Evans, Jenna Couture, Laura L. Quinn, Girija Anand, Liane Davis, Catherine Norman, Nelesh Jeyadevan, Farid Bazari, G. Atkin, Nicola H. Strickland, Dominic Yu, Shafi Ahmed, Jamila Roehrig, Imperial College Healthcare NHS Trust- BRC Funding, and Department of Health
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Pulmonary and Respiratory Medicine ,Male ,medicine.medical_specialty ,Lung Neoplasms ,Population ,Disease ,Streamline investigators ,Sensitivity and Specificity ,030218 nuclear medicine & medical imaging ,Metastasis ,law.invention ,03 medical and health sciences ,0302 clinical medicine ,Randomized controlled trial ,law ,Carcinoma, Non-Small-Cell Lung ,medicine ,Humans ,Whole Body Imaging ,Prospective Studies ,Neoplasm Metastasis ,education ,Lung cancer ,Adverse effect ,Lung ,Aged ,education.field_of_study ,Pregnancy ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,3. Good health ,England ,030220 oncology & carcinogenesis ,Female ,Radiology ,business ,Tomography, X-Ray Computed - Abstract
Summary Background Whole-body magnetic resonance imaging (WB-MRI) could be an alternative to multi-modality staging of non-small-cell lung cancer (NSCLC), but its diagnostic accuracy, effect on staging times, number of tests needed, cost, and effect on treatment decisions are unknown. We aimed to prospectively compare the diagnostic accuracy and efficiency of WB-MRI-based staging pathways with standard pathways in NSCLC. Methods The Streamline L trial was a prospective, multicentre trial done in 16 hospitals in England. Eligible patients were 18 years or older, with newly diagnosed NSCLC that was potentially radically treatable on diagnostic chest CT (defined as stage IIIb or less). Exclusion criteria were severe systemic disease, pregnancy, contraindications to MRI, or histologies other than NSCLC. Patients underwent WB-MRI, the result of which was withheld until standard staging investigations were complete and the first treatment decision made. The multidisciplinary team recorded its treatment decision based on standard investigations, then on the WB-MRI staging pathway (WB-MRI plus additional tests generated), and finally on all tests. The primary outcome was difference in per-patient sensitivity for metastases between standard and WB-MRI staging pathways against a consensus reference standard at 12 months, in the per-protocol population. Secondary outcomes were difference in per-patient specificity for metastatic disease detection between standard and WB-MRI staging pathways, differences in treatment decisions, staging efficiency (time taken, test number, and costs) and per-organ sensitivity and specificity for metastases and per-patient agreement for local T and N stage. This trial is registered with the International Standard Randomised Controlled Trial registry, number ISRCTN50436483, and is complete. Findings Between Feb 26, 2013, and Sept 5, 2016, 976 patients were screened for eligibility. 353 patients were recruited, 187 of whom completed the trial; 52 (28%) had metastasis at baseline. Pathway sensitivity was 50% (95% CI 37–63) for WB-MRI and 54% (41–67) for standard pathways, a difference of 4% (−7 to 15, p=0·73). No adverse events related to imaging were reported. Specificity did not differ between WB-MRI (93% [88–96]) and standard pathways (95% [91–98], p=0·45). Agreement with the multidisciplinary team's final treatment decision was 98% for WB-MRI and 99% for the standard pathway. Time to complete staging was shorter for WB-MRI (13 days [12–14]) than for the standard pathway (19 days [17–21]); a 6-day (4–8) difference. The number of tests required was similar WB-MRI (one [1–1]) and standard pathways (one [1–2]). Mean per-patient costs were £317 (273–361) for WBI-MRI and £620 (574–666) for standard pathways. Interpretation WB-MRI staging pathways have similar accuracy to standard pathways, and reduce the staging time and costs. Funding UK National Institute for Health Research.
- Published
- 2019
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13. Combined Statistical-Mechanical Characterization of a Next Generation Textured PTFE for Extreme Environments
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Ali P. Gordon, Sannmit Shinde, Steve Pitolaj, Zachary Poust, Jim Drago, and Paul Nichols
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Honeycomb structure ,Materials science ,visual_art ,Gasket ,visual_art.visual_art_medium ,Compressibility ,Ceramic ,Composite material ,Particulates ,Viscoelasticity ,Leakage (electronics) - Abstract
Pressurized vessels that transfer media from one location to another often contain a bolted connection. Gaskets are essential for these systems since they confer high levels of leak mitigation across of range of operating environments (i.e., internal pressure and temperature). The balance of both sealability and compressibility must be displayed in candidate gasket materials to be subjected to aggressive operating conditions. Historically, thin gauge gasket (i.e., 1/16” thick) confer high sealability while thick gaskets offer superior compressibility (i.e., 1/8”). Fabricated with skive cut, ceramic particle-reinforced PTFE, these materials display linear viscoelastic behavior that allow consolidation to occur. For example, GYLON® 3504 is filled with Aluminosilicate Microspheres, GYLON®3510 is filled with barium sulfate, respectively, to efficiently fill crevices along the surfaces of the flange. Novel textured PTFE gasket (3504 EPX and 3510 EPX) have been developed to simultaneously confer sealability and compressibility compared to flat products. A design of experiments (DoE) approach is applied to characterize the factors that influence load relaxation responses of the both candidate textured PTFE (dual-face honeycomb) and existing (flat) gasket styles. Using an instrumented test platform analyzed. A new parameter is presented to quantify gasket efficiency. The collection of efficiency measurement methods and approach to re-torque optimization convey a novel framework that designers can invoke to facilitate improved flange performance.
- Published
- 2018
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14. Application of Miniaturized Experiments for Constitutive Modeling of Creep Relaxation of a Novel Textured Gasket Product
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Evren Tasci, Ali P. Gordon, John Albury, Steve Pitolaj, Jim Drago, Matthew Lopez, Paul Nichols, and Zachary Poust
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Honeycomb structure ,Materials science ,Creep ,Product (mathematics) ,Gasket ,Constitutive equation ,Compressibility ,Torque ,Relaxation (approximation) ,Composite material - Abstract
The material attributes that are fundamental for developing a candidate textured, ceramic-filled PTFE gasket, such as texture style/dimensions, filler material, thickness and so on, create a set of potential combinations that are not practical to experimentally characterize at the component-level one-by-one. Optimizing gasket performance, however, is essential to the operation of bolted connections associated with pressurized vessels that transfer media from one location to another. Gaskets are essential for these systems since they confer high levels of leak mitigation across a range of operating environments. A balance of both compressibility and sealability must be displayed in an optimal candidate gasket to be subjected to aggressive operating conditions. A novel textured PTFE material (termed textured) characterized using a miniaturized test platform. This new-to-market viscoelastic material features a dual-face, raised honeycomb pattern. Experiments on both flat (termed Flat) and textured are used to identify viscoelastic constitutive model constants associated with Burger theories. Considering that the test platform contains an elastic bolt that is tightened to a prescribe torque level, the gasket is subjected to creep relaxation. Test results on the small samples contribute to constitutive modeling. The influence of parameters such as filler material selection, torque level, dwell period, etc. are presented.
- Published
- 2018
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15. Generation–recombination noise and photo-induced transient conductivity in epitaxial CdHgTe long wavelength infrared detectors
- Author
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Paul, Nichols, Van Vliet, Carolyne M., and Mergui, Sylvia
- Published
- 1999
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16. Commentary I
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Kristen Huff and Paul Nichols
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Process (engineering) ,Interpretation (philosophy) ,Psychological testing ,Context (language use) ,Psychology ,Cognitive response ,Variety (cybernetics) ,Test (assessment) ,Cognitive psychology - Abstract
This chapter explores the use of results from studies of cognitive response processes (CRPs) as evidence for claims supporting the interpretation and use of results from assessments of complex thinking and learning. CRPs are the moment-to-moment processes required to think and solve problems, are domain-specific, and change depending on the context of the assessment. The characterization of thinking and learning as complex raises challenges for the validation of results in educational and psychological assessment. Evidence for claims that complex thinking has been assessed may be obtained using a number of approaches including studies of verbal reports, eye movements, and log files. Conducting the domain analysis involved gathering information from a variety of sources including the latest research on CRPs. In addition, CRP may also be used as evidence for claims about the thinking and problem solving of actors involved in the assessment process other than test takers.
- Published
- 2017
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17. Population structure on breeding grounds of Lake Malawi’s ‘twilight zone’ cichlid fishes
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Paul W. Shaw, Paul Nichols, Gary R. Carvalho, Rosanna L. Robinson, George F. Turner, and Martin J. Genner
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Sympatry ,Genetic divergence ,Panmixia ,Ecology ,biology ,Sympatric speciation ,Allopatric speciation ,Biological dispersal ,Diplotaxodon ,Incipient speciation ,biology.organism_classification ,Ecology, Evolution, Behavior and Systematics - Abstract
Aim Free-ranging benthopelagic fishes often have large population sizes and high rates of dispersal. These traits can act to homogenize population structure across the distributional range of a species and to reduce the likelihood of allopatric speciation. The apparent absence of any barriers to gene flow among populations, together with prior molecular evidence for panmixia across the ranges of three species, has resulted in Diplotaxodon, a genus of benthopelagic cichlid fishes of Lake Malawi, being proposed as a candidate case of sympatric speciation. Our aim was to further investigate this possibility by testing for intraspecific genetic subdivision among breeding populations, and intraspecific differences in breeding habitat. Location Lake Malawi, central-east Africa. Methods We analysed eight microsatellite DNA loci to test for spatial genetic differences among populations on breeding grounds of eight Diplotaxodon species. We also tested for temporal population genetic differences within breeding grounds of three species. Records of ripe Diplotaxodon encountered during sampling were analysed to test if spatial variation in assemblage structure was linked to nearshore water depth and geographic proximity of sampling sites. Results Consistent with previous molecular evidence, within four of the eight species tested we found no evidence of spatial genetic structuring among breeding populations. However, within the other four species we found slight yet significant spatial genetic differences, indicating restricted gene flow among breeding grounds. There was no evidence of temporal genetic differences within sites. Analyses of the distributions of ripe Diplotaxodon revealed differences in assemblage structure linked to nearshore water depth. Main conclusions Together, these results demonstrate both the evolution of fidelity to deep-water breeding locations in some Diplotaxodon species, and differences in breeding habitat among species. These findings are consistent with a role for divergence of breeding habitat in speciation of these cichlids, possibly promoted by dispersal limitation among geographically segregated spawning aggregations.
- Published
- 2010
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18. Genetic homogeneity among breeding grounds and nursery areas of an exploited Lake Malawi cichlid fish
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Martin J. Genner, Gary R. Carvalho, Paul W. Shaw, George F. Turner, Paul Nichols, and Rosanna L. Robinson
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Pseudotropheus zebra ,education.field_of_study ,Ecology ,Population ,Biodiversity ,Aquatic Science ,Biology ,biology.organism_classification ,Haplochromine ,Habitat ,Cichlid ,Sympatric speciation ,parasitic diseases ,Species richness ,education - Abstract
1. Nursery areas are commonly recognized as important habitats for the management and conservation of fish stocks. Here we report the use of nursery areas by an exploited offshore cichlid in Lake Malawi, Rhamphochromis longiceps. 2. Like all haplochromine cichlids that have been studied, the species is a maternal mouthbrooder that broods eggs for several weeks following spawning. We found evidence that during this brooding period females migrate from open water to release juveniles in three shallow peripheral waterbodies (Chia Lagoon, Unaka Lagoon, Lake Malombe). However, it was unclear whether there is geographical population structuring within the species, which could indicate stock differences in their use of these nursery habitats, or if the lake contains a genetically panmictic population that employs nursery habitats opportunistically. 3. To investigate spatial and temporal population structuring within the lake we genotyped populations at seven microsatellite DNA loci. Overall, we found no significant spatial structuring among juveniles from the peripheral lagoons or among breeding males within the main lake body. Moreover, we found no evidence of temporal structuring among males on the breeding grounds within Lake Malawi or females entering Chia lagoon. Together, these results suggest that Lake Malawi contains a genetically homogeneous population of R. longiceps. 4. At present we know little of the distribution of juvenile R. longiceps elsewhere in the Lake Malawi basin, but their absence from surveyed rocky and sandy littoral habitats makes it possible that the species is dependent upon a small number of nearshore nursery areas, including these lagoons. As such, conservation of lagoon habitats and monitoring of exploited fish stocks within them may be important for effective preservation of biodiversity within the catchment.
- Published
- 2008
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19. Electrical fluctuations and photoinduced current transients in Cd...Hg...Te long wavelength...
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Paul, Nichols and Van Vliet, Carolyne M.
- Subjects
- *
MERCURY telluride , *INFRARED detectors , *ELECTRIC transients - Abstract
Studies the measurements of I-V characteristics, resistance versus T..., noise spectra and photoresponse for frequencies of 10 hertz-1 megahertz in the temperature range 300-50 K to cadmium-mercury telluride long-wavelength infrared detectors having epitaxial layers on band gap material. Measurement techniques; Noise and auxiliary data; Photoinduced current transient spectroscopy (PICTS) measurements.
- Published
- 1999
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20. Reproductive isolation among deep-water cichlid fishes of Lake Malawi differing in monochromatic male breeding dress
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Martin J. Genner, George F. Turner, Gary R. Carvalho, Paul Nichols, Rosanna L. Robinson, and Paul W. Shaw
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Pseudotropheus zebra ,biology ,Ecology ,Assortative mating ,Zoology ,Diplotaxodon ,Reproductive isolation ,biology.organism_classification ,Sympatric speciation ,Cichlid ,Sexual selection ,Genetics ,Species richness ,Ecology, Evolution, Behavior and Systematics - Abstract
Male nuptial colour hues are important for the maintenance of reproductive isolation among cichlid fish species, and environmental changes that lead to narrower light spectra can lead to hybridization. However, cichlid species can naturally co-occur in narrow light spectrum habitats, such as turbid shallow lakes and the deep benthic zones of African rift lakes. Closely related species from narrow light spectrum habitats tend to differ little in the palette of male nuptial colours, thus for these taxa differences in colour patterns may be more important than differences in colour hue for species recognition. To investigate this hypothesis we examined morphometric and genetic differentiation among males of four sympatric putative species within the deep-water genus Diplotaxodon . These taxa live in a narrow-light spectrum environment where only blue light is present, and males differ primarily in ‘monochromatic’ black, white and silver patterning of the body and fins. Significant genetic differentiation was present among taxa in both microsatellite DNA and mitochondrial DNA, including one pair with no significant morphometric differentiation. Thus, these taxa represent reproductively isolated biological species, a result consistent with male nuptial patterning being important for species recognition and assortative mating. As such, we suggest that narrow-light spectra need not always represent barriers to effective visually mediated mate recognition.
- Published
- 2006
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21. Chilaiditi's syndrome as a cause for shock
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Damian Mayo, Declan McDonnell, Sophie Tallulah Boddy, and Paul Nichols
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Male ,medicine.medical_specialty ,medicine.medical_treatment ,Article ,Angina ,Postoperative Complications ,Laparotomy ,Medicine ,Humans ,Hernia ,Chilaiditi Syndrome ,Coronary Artery Bypass ,Diagnostic Errors ,Aged, 80 and over ,Hernia, Diaphragmatic ,medicine.diagnostic_test ,Respiratory distress ,business.industry ,Shock ,General Medicine ,Emergency department ,medicine.disease ,Surgery ,Radiography ,Bypass surgery ,Shock (circulatory) ,medicine.symptom ,business ,Chest radiograph - Abstract
An 83-year-old man presented to the emergency department (ED) with tachycardia, hypotension and in respiratory distress. Eleven days prior to this he had undergone elective cardiac bypass surgery for angina. A chest radiograph was taken while in ED (figure 1), and shows a good example of Chilaiditi's sign, where bowel becomes interposed between the liver and diaphragm. He was referred to the general surgeons who performed an emergency laparotomy …
- Published
- 2015
22. Secondary contact seeds phenotypic novelty in cichlid fishes
- Author
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Harold Sungani, Paul J. Parsons, Cock van Oosterhout, Paul Nichols, Jennifer Swanstrom, Martin J. Genner, Domino A. Joyce, and Alan Smith
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Fish Proteins ,Malawi ,Genetic Speciation ,Population ,Molecular Sequence Data ,introgression ,Introgression ,haplochromine fishes ,General Biochemistry, Genetics and Molecular Biology ,Sexual Behavior, Animal ,Cichlid ,Phylogenetics ,Adaptive radiation ,phenotypic novelty ,Animals ,secondary contact ,education ,Research Articles ,Mozambique ,Phylogeny ,General Environmental Science ,Genetics ,education.field_of_study ,General Immunology and Microbiology ,biology ,Novelty ,General Medicine ,Reproductive isolation ,Cichlids ,Sequence Analysis, DNA ,biology.organism_classification ,river capture ,Phylogeography ,Phenotype ,admixture ,Hybridization, Genetic ,General Agricultural and Biological Sciences - Abstract
Theory proposes that genomic admixture between formerly reproductively isolated populations can generate phenotypic novelty for selection to act upon. Secondary contact may therefore be a significant promoter of phenotypic novelty that allows species to overcome environmental challenges and adapt to novel environments, including during adaptive radiation. To date, this has largely been considered from the perspective of interspecific hybridization at contact zones. However, it is also possible that this process occurs more commonly between natural populations of a single species, and thus its importance in adaptive evolution may have been underestimated. In this study, we tested the consequences of genomic introgression during apparent secondary contact between phenotypically similar lineages of the riverine cichlid fishAstatotilapia calliptera. We provide population genetic evidence of a secondary contact zone in the wild, and then demonstrate using mate-choice experiments that both lineages can reproduce together successfully in laboratory conditions. Finally, we show that genomically admixed individuals display extreme phenotypes not observed in the parental lineages. Collectively, the evidence shows that secondary contact can drive the evolution of phenotypic novelty, suggesting that pulses of secondary contact may repeatedly seed genetic novelty, which when coupled with ecological opportunity could promote rapid adaptive evolution in natural circumstances.
- Published
- 2015
23. A review of the current status and prospects for the US mid-level hotel sector: A survivor in uncertain times
- Author
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John Paul Nichols
- Subjects
Finance ,Occupancy ,business.industry ,media_common.quotation_subject ,Business travel ,Recession ,Tourism, Leisure and Hospitality Management ,Economics ,Demographic economics ,Business and International Management ,Investment opportunities ,High Street ,business ,Consumer behaviour ,media_common - Abstract
It is no secret that one of the hardest-hit industries in the USA since September 11 has been the lodging industry. As a result, hotel demand, occupancy and new construction have reached their lowest points since the early 1990s. Despite this, the mid-level hotel segment has continued to remain strong, experiencing the lowest declines of any segment. Tighter budgets, more drivers on the road and continued strength in leisure travel have all contributed to the mid-scale's stability during this period of recession.
- Published
- 2002
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24. Fulfilling the Promise of the Learning Triangle
- Author
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Paul Nichols
- Subjects
Statistics and Probability ,Applied Mathematics ,Pedagogy ,Learning theory ,Mathematics education ,Education ,Mathematics - Published
- 2011
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25. Prophesying the Reliability of Cognitively Complex Assessments
- Author
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Paul Nichols and Barbara Jean Kuehl
- Subjects
Developmental and Educational Psychology ,Psychology ,Reliability (statistics) ,Education ,Cognitive psychology ,Cognitive test - Abstract
(1999). Prophesying the Reliability of Cognitively Complex Assessments. Applied Measurement in Education: Vol. 12, No. 1, pp. 73-94.
- Published
- 1999
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26. PIGEONS' PREFERENCE FOR VARIABLE-INTERVAL WATER REINFORCEMENT UNDER WIDELY VARIED WATER BUDGETS
- Author
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David A. Case, Edmund Fantino, and Paul Nichols
- Subjects
Male ,Behavior, Animal ,Variable interval ,Pecking order ,Drinking Behavior ,Experimental and Cognitive Psychology ,Choice Behavior ,Behavioral Neuroscience ,Behavioral ecology ,Economic context ,Statistics ,Animals ,Conditioning, Operant ,Columbidae ,Psychology ,Reinforcement ,Reinforcement, Psychology ,Social psychology ,Water budget ,Preference (economics) ,Closed economy ,Research Article - Abstract
Water budget of pigeons was varied to assess the dependence of risk-sensitive preferences upon economic context such as has been reported for energy-budget manipulations with small animals in behavioral ecology research. Fixed- and variable-interval terminal-link water schedules reinforced choice between equal variable-interval initial-link schedules arranged on two pecking keys. While keeping a severely restrictive budget the same across three phases of the experiment, a contrasting distinct ample budget was arranged in each. To mimic typical methods in behavioral ecology studies, in each ample budget a more than three-fold increase in amount of water per reinforcer presentation was instituted simultaneously with significantly increased overall access to water. Total choice response rates plummeted in the ample budgets, and body weights either increased significantly or remained unchanged in different phases as expected by the nature of the different manipulations. Clear preferences for the variable-interval schedule were found throughout the experiment, except for rare instances of key bias. The results agree with similar operant food-reinforcement studies and extend conditions under which risk preference apparently does not depend upon economic context.
- Published
- 1995
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27. Bringing the excitement and motivation of research to students; Using inquiry and research-based learning in a year-long biochemistry laboratory : Part II-research-based laboratory-a semester-long research approach using malate dehydrogenase as a research model
- Author
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Jennifer Smith, Paul Nichols, Joseph J. Provost, Kristopher Knutson, and Mark A. Wallert
- Subjects
media_common.quotation_subject ,education ,Research opportunities ,Laboratory results ,Biochemistry ,Research based learning ,Variety (cybernetics) ,Learning experience ,Course evaluation ,ComputingMilieux_COMPUTERSANDEDUCATION ,Function (engineering) ,Psychology ,Molecular Biology ,Independent research ,media_common - Abstract
Research-based learning in a teaching environment is an effective way to help bring the excitement and experience of independent bench research to a large number of students. The program described here is the second of a two-semester biochemistry laboratory series. Here, students are empowered to design, execute and analyze their own experiments for the entire semester. This style of laboratory replaces a variety of shorter labs in favor of an in depth research-based learning experience. The concept is to allow students to function in independent research groups. The research projects are focused on a series of wild-type and mutant clones of malate dehydrogenase. A common research theme for the laboratory helps instructors administer the course and is key to delivering a research opportunity to a large number of students. The outcome of this research-based learning laboratory results in students who are much more confident and skilled in critical areas in biochemistry and molecular biology. Students with research experience have significantly higher confidence and motivation than those students without a previous research experience. We have also found that all students performed better in advanced courses and in the workplace.
- Published
- 2011
28. Case Study 3: The Thames Herring Drift-Net Fishery
- Author
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Paul Nichols and Paul Medley
- Subjects
Fishery ,Herring ,Oceanography ,Environmental science ,Fisheries management ,North sea - Published
- 2007
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29. Evolution of a cichlid fish in a Lake Malawi satellite lake
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Rosanna L. Robinson, George F. Turner, Paul W. Shaw, Gary R. Carvalho, Martin J. Genner, Paul Nichols, and Alan D. Smith
- Subjects
Male ,Genetic Speciation ,Population ,Allopatric speciation ,Biodiversity ,Color ,Fresh Water ,General Biochemistry, Genetics and Molecular Biology ,Cichlid ,parasitic diseases ,Animals ,education ,Phylogeny ,General Environmental Science ,education.field_of_study ,General Immunology and Microbiology ,biology ,Geography ,Ecology ,General Medicine ,Reproductive isolation ,Cichlids ,Incipient speciation ,Mating Preference, Animal ,biology.organism_classification ,Biological Evolution ,Rhamphochromis ,Phenotype ,Habitat ,Haplotypes ,Social Isolation ,Female ,General Agricultural and Biological Sciences ,Research Article - Abstract
Allopatric divergence in peripheral habitats may lead to rapid evolution of populations with novel phenotypes. In this study we provide the first evidence that isolation in peripheral habitats may have played a critical role in generation of Lake Malawi's cichlid fish diversity. We show that Lake Chilingali, a satellite lake 11.5 km from the shore of Lake Malawi, contains a breeding population of Rhamphochromis , a predatory genus previously thought to be restricted to Lake Malawi and permanently connected water bodies. The Lake Chilingali population is the smallest known Rhamphochromis , has a unique male nuptial colour pattern and has significant differentiation in mitochondrial DNA from Lake Malawi species. In laboratory mate choice trials with a candidate sister population from Lake Malawi, females showed a strong tendency to mate assortatively indicating that they are incipient biological species. These data support the hypothesis that isolation and reconnection of peripheral habitats due to lake level changes have contributed to the generation of cichlid diversity within African lakes. Such cycles of habitat isolation and reconnection may also have been important in evolutionary diversification of numerous other abundant and wide-ranging aquatic organisms, such as marine fishes and invertebrates.
- Published
- 2007
30. Reproductive isolation among deep-water cichlid fishes of Lake Malawi differing in monochromatic male breeding dress
- Author
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Martin J, Genner, Paul, Nichols, Gary R, Carvalho, Rosanna L, Robinson, Paul W, Shaw, and George F, Turner
- Subjects
Male ,Malawi ,Sex Characteristics ,Biometry ,Light ,Pigmentation ,Reproduction ,Fresh Water ,Cichlids ,Locus Control Region ,DNA, Mitochondrial ,Sexual Behavior, Animal ,Africa ,Animals ,Microsatellite Repeats - Abstract
Male nuptial colour hues are important for the maintenance of reproductive isolation among cichlid fish species, and environmental changes that lead to narrower light spectra can lead to hybridization. However, cichlid species can naturally co-occur in narrow light spectrum habitats, such as turbid shallow lakes and the deep benthic zones of African rift lakes. Closely related species from narrow light spectrum habitats tend to differ little in the palette of male nuptial colours, thus for these taxa differences in colour patterns may be more important than differences in colour hue for species recognition. To investigate this hypothesis we examined morphometric and genetic differentiation among males of four sympatric putative species within the deep-water genus Diplotaxodon. These taxa live in a narrow-light spectrum environment where only blue light is present, and males differ primarily in 'monochromatic' black, white and silver patterning of the body and fins. Significant genetic differentiation was present among taxa in both microsatellite DNA and mitochondrial DNA, including one pair with no significant morphometric differentiation. Thus, these taxa represent reproductively isolated biological species, a result consistent with male nuptial patterning being important for species recognition and assortative mating. As such, we suggest that narrow-light spectra need not always represent barriers to effective visually mediated mate recognition.
- Published
- 2007
31. Calibration Tests of New Type Flow-Metering System by Ultrasonic Pulse-Doppler Profile-Velocimetry at National Standard Loops
- Author
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Mark Sapia, Michitsugu Mori, Paul Nichols, Yasushi Takeda, Edward Schrull, Takeshi Suzuki, and Kenichi Tezuka
- Subjects
Engineering ,Pulse-Doppler radar ,business.industry ,Nuclear engineering ,Calibration ,Mechanical engineering ,NIST ,Ultrasonic sensor ,National standard ,Velocimetry ,business ,Flow metering ,Metrology - Abstract
To verify high accuracy of a new type flow-metering system based on the measurements of line velocity profiles, eliminating Profile Factors, calibration tests of “UDF”, the flow-metering system by ultrasonic pulse-Doppler profile-velocimetry, were conducted at national standard loops worldwide, including the National Institute of Standard Technology (NIST) of the U.S. Department of Commerce, the National Metrology Institute of Japan (NMIJ) of the National Institute of Advanced Industrial Science and Technology (AIST) in Japan, the Nederlands Meetinstituut (NMI) in Netherlands, and the Centro National de Metrologia (CENAM) in Mexico. The deviations of UDF to the standard loops in the calibration tests for water were found between −0.23% and +0.26% at NIST, 0.1% and 0.4% at NMIJ, and −0.52% and +0.59% at NMI in terms of the average values of each measurement. Following improvements to the UDF System, the calibration tests at CENAM exhibited the deviations between −0.18% and +0.23% and the expanded uncertainty with ±0.21%.Copyright © 2006 by ASME
- Published
- 2006
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32. Determining Plant – Leaf Miner – Parasitoid Interactions: A DNA Barcoding Approach
- Author
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Darren M. Evans, Stephane A. P. Derocles, Paul Nichols, David H. Lunt, and S. Aifionn Evans
- Subjects
Species complex ,Food Chain ,Insecta ,Molecular Sequence Data ,lcsh:Medicine ,Leaf miner ,DNA barcoding ,Parasitoid ,Electron Transport Complex IV ,Botany ,Animals ,DNA Barcoding, Taxonomic ,lcsh:Science ,Phylogeny ,DNA Primers ,Multidisciplinary ,Base Sequence ,biology ,Community ,lcsh:R ,fungi ,food and beverages ,Plants ,biology.organism_classification ,Ecological network ,Plant Leaves ,Plant ecology ,DNA profiling ,Larva ,lcsh:Q ,Research Article - Abstract
A major challenge in network ecology is to describe the full-range of species interactions in a community to create highly-resolved food-webs. We developed a molecular approach based on DNA full barcoding and mini-barcoding to describe difficult to observe plant – leaf miner – parasitoid interactions, consisting of animals commonly regarded as agricultural pests and their natural enemies. We tested the ability of universal primers to amplify the remaining DNA inside leaf miner mines after the emergence of the insect. We compared the results of a) morphological identification of adult specimens; b) identification based on the shape of the mines; c) the COI Mini-barcode (130 bp) and d) the COI full barcode (658 bp) fragments to accurately identify the leaf-miner species. We used the molecular approach to build and analyse a tri-partite ecological network of plant – leaf miner – parasitoid interactions. We were able to detect the DNA of leaf-mining insects within their feeding mines on a range of host plants using mini-barcoding primers: 6% for the leaves collected empty and 33% success after we observed the emergence of the leaf miner. We suggest that the low amplification success of leaf mines collected empty was mainly due to the time since the adult emerged and discuss methodological improvements. Nevertheless our approach provided new species-interaction data for the ecological network. We found that the 130 bp fragment is variable enough to identify all the species included in this study. Both COI fragments reveal that some leaf miner species could be composed of cryptic species. The network built using the molecular approach was more accurate in describing tri-partite interactions compared with traditional approaches based on morphological criteria.
- Published
- 2015
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33. Abdominal actinomycosis presenting as psoas abscess
- Author
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Simon Dennis, Asha Senapati, Paul Nichols, and Nicholas Marley
- Subjects
Adult ,medicine.medical_specialty ,Abdominal Abscess ,Diagnostico diferencial ,Penicillins ,Actinomycosis ,Diagnosis, Differential ,03 medical and health sciences ,0302 clinical medicine ,Abdominal actinomycosis ,X ray computed ,Medicine ,Humans ,030212 general & internal medicine ,Abscess ,biology ,business.industry ,General Medicine ,medicine.disease ,Actinomyces israelii ,biology.organism_classification ,030227 psychiatry ,Surgery ,medicine.anatomical_structure ,Abdomen ,Psoas Abscess ,Female ,Radiology ,business ,Tomography, X-Ray Computed ,Beta lactam antibiotics ,Research Article - Published
- 2000
34. 1. Social Survey Methods
- Author
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Paul Nichols
- Published
- 2000
- Full Text
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35. Prelims - Social Survey Methods
- Author
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Paul Nichols
- Subjects
General Social Survey ,Sociology ,Social science - Published
- 2000
- Full Text
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36. A review of the current status and prospects for the US mid-level hotel sector: A survivor in uncertain times
- Author
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Paul Nichols, John, primary
- Published
- 2002
- Full Text
- View/download PDF
37. Evolution of a cichlid fish in a Lake Malawi satellite lake.
- Author
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Paul Nichols, Gary R. Carvalho, Rosanna L. Robinson, Paul W. Shaw, and Alan Smith
- Subjects
- *
CICHLIDS , *RADIOACTIVE substances in rivers, lakes, etc. , *AQUATIC biology - Abstract
Allopatric divergence in peripheral habitats may lead to rapid evolution of populations with novel phenotypes. In this study we provide the first evidence that isolation in peripheral habitats may have played a critical role in generation of Lake Malawi's cichlid fish diversity. We show that Lake Chilingali, a satellite lake 11.5km from the shore of Lake Malawi, contains a breeding population of Rhamphochromis, a predatory genus previously thought to be restricted to Lake Malawi and permanently connected water bodies. The Lake Chilingali population is the smallest known Rhamphochromis, has a unique male nuptial colour pattern and has significant differentiation in mitochondrial DNA from Lake Malawi species. In laboratory mate choice trials with a candidate sister population from Lake Malawi, females showed a strong tendency to mate assortatively indicating that they are incipient biological species. These data support the hypothesis that isolation and reconnection of peripheral habitats due to lake level changes have contributed to the generation of cichlid diversity within African lakes. Such cycles of habitat isolation and reconnection may also have been important in evolutionary diversification of numerous other abundant and wide-ranging aquatic organisms, such as marine fishes and invertebrates. [ABSTRACT FROM AUTHOR]
- Published
- 2007
38. The Social Teaching of the Black Churches By Peter J. Paris Philadelphia, Fortress, 1985. 156 pp. $8.95
- Author
-
Paul Nichols
- Subjects
media_common.quotation_subject ,Religious studies ,Art ,Fortress (chess) ,Theology ,media_common - Published
- 1985
- Full Text
- View/download PDF
39. Clouds And Methane Photochemical Hazes On The Outer Planets.
- Author
-
Romani, Paul Nichols
- Subjects
- Clouds, Hazes, Methane, Outer, Photochemical, Planets
- Abstract
A numerical model which uses thermodynamic and hydrostatic equilibrium was developed to study the cloud structure of the outer planets: Jupiter, Saturn, Uranus and Neptune. The model calculates cloud locations, cloud densities, the mixing ratio profiles of the condensates, and the thermal structure from the appropriate wet/dry adiabatic lapse rate. The effects of ortho-to-para H(,2) conversion (latent heat release and change in heat capacity of H(,2)) are also considered. The outer planets are predicted to have a multilayered cloud structure consisting of one or more of the following clouds: NH(,3)-H(,2)O solution, H(,2)O-ice, NH(,3)-ice, NH(,4)SH-solid, H(,2)S-ice, or CH(,4)-ice. Model predictions are compared to relevant observations. In particular, the observed NH(,3) depletion on Uranus is consistent with loss into an extensive NH(,3)-H(,2)O solution cloud, and it is not necessary to selectively enrich H(,2)S to NH(,3). Following condensation in the troposphere, CH(,4) remains the only trace gas that is present in large enough abundance in the stratospheres of Uranus and Neptune to be photolyzed. The coupled continuity equations for CH(,4), CH(,3), C(,2)H(,2), C(,2)H(,4), C(,2)H(,6), and H were solved numerically. Comparison of model predictions to observations provides constraints on eddy mixing. The predicted C(,2)H(,6) abundances are in agreement with the detection of C(,2)H(,6) in emission in the IR from Neptune but not from Uranus. For both planets, the calculated mixing ratios of CH(,2) and C(,2)H(,6) are large enough to form ice hazes in the vicinity of the tropopause. Coupled cloud physics and Mie scattering calculations favor ice particles with radii 10(mu) or larger to explain the observed clarity in the visible spectrum for this atmospheric region. For Uranus, polyacetylene production will also contribute to aerosols at this layer.
- Published
- 1986
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