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Rowlands, Don, Mike Smith, Ingereth Macfarlane, Duncan Wright, and Max Tischler. "The lost oasis: Archaeology of a ‘forgotten’ mikiri well in the Simpson Desert." Queensland Archaeological Research 23 (March 5, 2020): 1–7. http://dx.doi.org/10.25120/qar.23.2020.3717.
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This paper describes a previously unknown mikiri well in the Simpson dune field. This site was abandoned about 500-600 years ago and does not feature in ethnographic records for this region. We argue that its abandonment was most likely due to failure of the well caused by a fall in the local watertable. The Simpson Desert is one of the major sand-ridge deserts of the world, but current views of the chronology of human use of this vast dune field rest on only a handful of radiocarbon ages (n=12). The radiocarbon ages for this mikiri, and its surroundings, add to this limited dataset. We plot all available radiocarbon ages from archaeological sites in the dune field showing that occupation of this mikiri coincided with a widespread increase in use of the dune field during the last millennium, at about the time the Wangkanguru people in the dune field were becoming linguistically distinct from the Arabana to the west.
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Sughrue, Michael E., Ari J. Kane, Gopal Shangari, Martin J. Rutkowski, Michael W. McDermott, Mitchel S. Berger, and Andrew T. Parsa. "The relevance of Simpson Grade I and II resection in modern neurosurgical treatment of World Health Organization Grade I meningiomas." Journal of Neurosurgery 113, no. 5 (November 2010): 1029–35. http://dx.doi.org/10.3171/2010.3.jns091971.
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Object In 1957, Simpson published a seminal paper defining the risk factors for recurrence following surgical treatment of intracranial meningiomas. Given that Simpson's study was published more than 50 years ago, preceding image guidance technology and MR imaging, the authors reviewed their own experience with surgical treatment of Grade I meningiomas to determine if Simpson's grading scale is still relevant to modern neurosurgical practice. Methods From this cohort, the authors evaluated all patients undergoing craniotomy for resection of a histologically proven WHO Grade I meningioma as their initial therapy. Clinical information was retrospectively reconstructed using patient medical records and radiological data. Recurrence analysis was performed using the Kaplan-Meier method. Results The 5-year recurrence/progression-free survival for all patients receiving a Simpson Grade I, II, III, or IV resection was 95, 85, 88, and 81%, respectively (p = not significant, log-rank test). Kaplan-Meier analysis revealed no significant difference in recurrence-free survival between patients receiving a Simpson Grade I, II, III, or IV resection. Analysis limited to meningiomas arising from the skull base (excluding the cavernous sinus) similarly found no significant benefit to Simpson Grade I or II resection, and the survival curves were nearly superimposed. Conclusions In this study of a cohort of patients undergoing surgery for WHO Grade I meningiomas, the authors demonstrate that the benefit of more aggressive attempts to resect the tumor with dura and underlying bone was negligible compared with simply removing the entire tumor, or even leaving small amounts of tumor attached to critical structures. The authors believe that these data reflect an evolution in the nature of meningioma surgery over the past 2 decades, and bring into question the relevance of using Simpson's grading system as the sole predictor of recurrence.
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Hu, Zhiming, and Chong Liu. "An Improved Nonequidistant Grey Model Based on Simpson Formula and Its Application." Complexity 2021 (April 29, 2021): 1–11. http://dx.doi.org/10.1155/2021/6654324.
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Grey prediction models have been widely used in various fields of society due to their high prediction accuracy; accordingly, there exists a vast majority of grey models for equidistant sequences; however, limited research is focusing on nonequidistant sequence. The development of nonequidistant grey prediction models is very slow due to their complex modeling mechanism. In order to further expand the grey system theory, a new nonequidistant grey prediction model is established in this paper. To further improve the prediction accuracy of the NEGM (1, 1, t2) model, the background values of the improved nonequidistant grey model are optimized based on Simpson formula, which is abbreviated as INEGM (1, 1, t2). Meanwhile, to verify the validity of the proposed model, this model is applied in two real-world cases in comparison with three other benchmark models, and the modeling results are evaluated through several commonly used indicators. The results of two cases show that the INEGM (1, 1, t2) model has the best prediction performance among these competitive models.
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Satish Kumar, Sunit Kumar,. "GINI SIMPSON INDEX FOR PICTURE FUZZY SETS WITH THEIR APPLICATION IN MULTI -ATTRIBUTE DECISION MAKING PROCESS." INFORMATION TECHNOLOGY IN INDUSTRY 9, no. 1 (March 10, 2021): 680–90. http://dx.doi.org/10.17762/itii.v9i1.187.
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In present paper, we proposed a Gini Simpson index for picture fuzzy set with their application in MADM and discuss it’s properties which are investigated in a mathematical framework. We developed an algorithm based on TODIM(An acronym in Portuguess for interactive multi-attribute decision making) which we applied ton the proposed entropy to solve the MADM problems under the picture fuzzy environment when the criteria weights are completely known. With took a numerical example on Muthoot Finance Limited to demonstrate the applicability and feasibility of the proposed approach.
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Hammer, Paul E. J. "Sir Henry Lee (1533–1611): Elizabethan Courtier. Sue Simpson. Farnham: Ashgate Publishing Limited, 2014. xii + 244 pp. $124.95." Renaissance Quarterly 69, no. 1 (2016): 303–5. http://dx.doi.org/10.1086/686388.
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Done, G. S. T. "Matrices and Engineering Dynamics. A. R. Collar and A. Simpson. Ellis Horwood Limited, Chichester. 1987. 541 pp. Illustrated. £65.00." Aeronautical Journal 92, no. 916 (July 1988): 244. http://dx.doi.org/10.1017/s0001924000016201.
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Wu, Qiuxin, and Gregory M. Mueller. "Biogeographic relationships between the macrofungi of temperate eastern Asia and eastern North America." Canadian Journal of Botany 75, no. 12 (December 1, 1997): 2108–16. http://dx.doi.org/10.1139/b97-922.
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Eastern North America and temperate eastern Asia reportedly share a relatively high number of taxa of macrofungi (mushrooms and relatives), including a number of taxa that have putative eastern North America – temperate eastern Asia disjunct distributions. These reports have been used to imply an affinity between the mycota (fungal equivalent of flora and fauna) of the two regions. To date, however, this affinity has not been examined in detail. A comparison of north temperate macrofungal mycotas was undertaken to examine the similarity between these regions. We used two methods in this study: (i) direct comparison of taxon lists and (ii) calculation of the Simpson Coefficient of similarity from lists of selected taxa. These analyses were based on field work, herbarium records, and published taxonomic treatments for Amanita, Lactarius, Ramaria, and Boletaceae. Results of these analyses document that taxonomic similarity between eastern North America and temperate eastern Asia mycotas can be quite high. In all cases, the calculated similarity values for eastern North America – temperate eastern Asia comparisons are higher than those between either region of North America and Europe or between western North America and eastern Asia. Furthermore, the eastern North American and temperate eastern Asian disjunct distributions of macrofungi are usually limited to the level of species or lower. Key words: biogeography, China, disjunct distribution, macrofungi, North America, Simpson Coefficient.
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Quiñones-Hinojosa, Alfredo, Edward F. Chang, Kaisorn L. Chaichana, and Michael W. McDermott. "SURGICAL CONSIDERATIONS IN THE MANAGEMENT OF FALCOTENTORIAL MENINGIOMAS: ADVANTAGES OF THE BILATERAL OCCIPITAL TRANSTENTORIAL/TRANSFALCINE CRANIOTOMY FOR LARGE TUMORS." Operative Neurosurgery 64, suppl_5 (May 1, 2009): ons260—ons268. http://dx.doi.org/10.1227/01.neu.0000344642.98597.a7.
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Abstract OBJECTIVE Meningiomas arising from the falcotentorial junction are relatively rare, and the description of the surgical nuances in approaching these tumors is limited. We describe our surgical management of these lesions in detail. METHODS From 2001 to 2005, 9 patients underwent operation for meningiomas arising from the falcotentorial junction, with some extending to and/or invading the torcula. All patients were assessed preoperatively with magnetic resonance neuroimaging and cerebral angiography. Furthermore, preoperative embolization was attempted in all cases. A supratentorial/infratentorial torcular craniotomy technique was used in all but 1 of these cases. RESULTS The average dimensions of the falcotentorial meningiomas were 5.1 × 4.4 × 4.2 cm. The angiograms revealed that these tumors were fed by branches of the internal carotid artery, choroidal arteries, branches of the meningohypophyseal trunk, and branches of the posterior cerebral artery. Preoperative embolization was achieved in only 2 patients. Five patients had gross total resection (Simpson grade 1), and 4 had subtotal resection (Simpson grade 4). Two of the tumors (22%) recurred during a mean follow-up period of 49 months (range, 17–88 months). The most common complication after surgery was cortical blindness, but all postoperative visual deficits had fully recovered at the last follow-up evaluation within several months. CONCLUSION An excellent outcome can be expected with detailed preoperative neuroimaging and knowledge of the nuances of the surgical technique that we describe in detail in this article.
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He, Meng Xuan, Hong Yuan Li, Lan Lan Li, and Fang Wang. "Study on Soil Seed Bank in Urban Abandoned Land of Tianjin — Take Houtai Wetland for Example." Applied Mechanics and Materials 448-453 (October 2013): 978–82. http://dx.doi.org/10.4028/www.scientific.net/amm.448-453.978.
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Urban abandoned lands play an important role to maintain urban biodiversity. In order to study the characteristics of soil seed bank (SSB) in Houtai Wetland, field survey and laboratory experiment were conducted. After germination test, the results show that the species richness is relatively low, only 12 kinds of species are contained, but the reserves of SSB are abundant. Its density reaches to7.27×105grains/m2, maintaining the same level with coastal wetlands. Glycine soja account for the vast majority of proportion, leading to uneven distribution within species.So the Shannon-Wiener Diversity Index, Simpson Index and Pielou Evenness Index are all lower than ground vegetation.The Sorensen Similarity Index is 0.330, its ability to reproduce ground plants is limited. The suggestions are that appropriate manners should be taken to protect native plants and soil seed bank.
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Wang, Chong Lin. "A Solution for Diffusion Equations and the Distribution of Alloying Elements in Sintered Alloys." Materials Science Forum 534-536 (January 2007): 481–84. http://dx.doi.org/10.4028/www.scientific.net/msf.534-536.481.
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The error function can be calculated based on the Simpson method through a subroutine program. An integration program by FORTRAN language was made for diffusion equations of extended source with infinite extent and limited extent. The distribution curves of alloying elements could be driven from calculated results written in ASCII code. The results on some alloying elements such as C, Co, Cr, Mn, Mo, Ni and V’s diffusion in iron, showed the diffusion distance for Ni and Mo can only be 1~3 μm and more distance for Co at common sintering temperature of 1120°C. Increasing the sintering temperature up to 1300°C, distribution curve could be improved. To refine the particle size of the added elements down to a scale of micrometers is an effective way to get homogeneous distribution.
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Recski, Leonardo Juliano. ""… It's Really Ultimately Very Cruel …": contrasting English intensifier collocations across EFL writing and academic spoken discourse." DELTA: Documentação de Estudos em Lingüística Teórica e Aplicada 20, no. 2 (December 2004): 211–34. http://dx.doi.org/10.1590/s0102-44502004000200002.
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This paper investigates and contrasts recurrent intensifier collocations across a corpus of EFL writing - The International Corpus of Learner English - ICLE (Granger, 1993) and The Michigan Corpus of Academic Spoken English - MICASE (Simpson et al., 2002). It seeks to show that such recurrent collocations are an important part of writers and speakers' linguistic repertoire and that they may provide a window onto their lexicon. On general grounds, the results indicate that there is a great predominance of boosters over maximizers and that a limited number of maximizers and boosters are used in recurrent combinations. The analysis further revealed that maximizers tend to intensify non-gradable words while boosters tend to intensify gradable ones and that EFL writers' overuse of intensifiers appears to be associated with colloquial style and an exaggerated tone that is often considered to be inappropriate in formal academic texts.
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Vianna, M. F., S. Pelizza, M. L. Russo, S. Rodriguez, and A. C. Scorsetti. "Fungal endophytes: isolation and diversity among Nicotiana tabacum (Solanaceae) organs." Acta Botanica Hungarica 62, no. 1-2 (March 2020): 175–86. http://dx.doi.org/10.1556/034.62.2020.1-2.11.
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The diversity of fungal endophytes is poorly known and particularly in the case of Nicotiana tabacum, the literature is limited. The present study assessed and compared the diversity and distribution of endophytic fungi between different organs of tobacco plants. We calculated the relative frequency and rates of colonisation and of isolation of endophytic fungi in roots, stems and leaves, as well as the Shannon–Wiener and Simpson diversity indexes. Similarities between assemblages from the studied organs were also analysed. A total of 1588 endophytic fungal strains assigned to 31 morphospecies were isolated. The highest diversity of endophytes was found in leaves, being Fusarium graminearum and Alternaria botrytis the most common fungal species. This study provides information on the distribution of fungal endophytes inhabiting leaves, stems, and roots of N. tabacum and thus can serve as a starting point for increasing our comprehension on the interactions in which these fungi are involved.
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CRACKNELL, A. P. "Review of: “Gravity Currents: In the Environment and the Laboratory”. By J. E. Simpson. (Chichester: Ellis Horwood Limited, 1987.) [Pp. 244.] Price £3500." International Journal of Remote Sensing 9, no. 6 (June 1988): 1135. http://dx.doi.org/10.1080/01431168808954919.
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Mooney, Michael A., Walid Ibn Essayed, and Ossama Al-Mefty. "Nuances of Olfactory Groove Meningioma Surgery: 2-Dimensional Operative Video." Operative Neurosurgery 21, no. 4 (June 30, 2021): E338—E339. http://dx.doi.org/10.1093/ons/opab233.
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Abstract Olfactory groove meningiomas frequently present as large or giant-size tumors associated with marked frontal lobe edema and significant frontal lobe dysfunction. Simpson grade I removal was rare in early reports due to their invasion of the ethmoid sinuses and skull base bone,1 which resulted in high recurrence rates.2,3 Indeed, recurrence occurred in the most celebrated case of olfactory groove meningioma.4,5 To achieve Simpson grade I removal (tumor, dura, bone), protect the frontal lobes from additional injury, and provide the best chance for recovery, we demonstrate a few nuances for olfactory groove meningioma surgery: Utilizing a skull base approach with a low dural opening, the frontal veins are preserved, and the frontal lobe is protected from retraction, manipulation, and venous injury. By the time of diagnosis, although the patient's olfaction is often absent, there still remains a role to preserve at least 1 olfactory tract, which might yield some preservation in a limited number of patients. Emphasis has been rightly made on the preservation of the A2 segments, which can be dissected using microsurgical technique. Lastly, multilayer reconstruction of the skull base is required, using an inlay graft, resting on a vascularized pericranial flap, and occlusion of the sinuses with a fat graft. The endonasal endoscopic approach has fallen out of favor due to limitations for complete tumor resection and higher complication rates.6 We present a case of a relatively small olfactory groove meningioma in a 36-yr-old male with partial olfactory loss. The patient consented for surgery. Images at 2:07, 2:29, and 2:54 from Al-Mefty O, Operative Atlas of Meningiomas, © LWW, 1997, with permission. Image at 8:31 public domain by age.
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OGOREVC, Marko, and Renata SLABE-ERKER. "Assessment of the European Common Agricultural Policy and landscape changes: an example from Slovenia." Agricultural Economics (Zemědělská ekonomika) 64, No. 11 (November 26, 2018): 489–98. http://dx.doi.org/10.17221/337/2017-agricecon.
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The objective of this study was to determine whether and to what extent Common Agricultural Policy (CAP) measures actually succeed in preserving the diversity of agricultural landscapes. This paper assesses the effects of agricultural policy on changes in the diversity of agricultural landscapes in Slovenia. Diversity is measured by the Shannon index and the Simpson index, while the impacts were estimated using a spatial lag model. The results show that direct payments decrease landscape diversity by 2 index points per 1 000 EUR/ha, but agri-environmental payments for reducing negative impacts on the environment and those for nature conservation increase agricultural landscape diversity by 2.8 index points and 12.30 index points per 1 000 EUR/ha, respectively. Furthermore, we did not find any statistically significant effects of habitat protection payments on landscape diversity. Since direct payments are almost four times larger on average as agri-environmental payments, they preserve landscape diversity only to a limited extent.
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Padmanabhan, T., and M. M. Vasanthi. "Cosmological Consequences of an Unstable Heavy Neutrino." Symposium - International Astronomical Union 117 (1987): 493. http://dx.doi.org/10.1017/s0074180900150739.
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In a recent paper Simpson has reported evidence for a heavy neutrino of about 17.1 kev mass. Cosmological bounds on stable neutrino species imply that this neutrino [νH] must be unstable. The most likely decay mode νH→νL+f where νL is a light neutrino and f is a scalar boson leads to a cosmological scenario which is quite different from the conventional picture. In this scenario universe becomes matter dominated at a redshift of z ∼ 107 and becomes radiation dominated [by the decay product νL of νH] at z ∼ 310. The kinematic constraints on the lifetime of νH do not lead to any contradictions. On the other hand, growth of baryonic perturbations is severely limited in this model due to two reasons: (i) virtually no growth can take place in the radiation dominated region z ≤ 310. (ii) Decay of νH is likely to disrupt and smoothen out past growth by a large factor. It is doubtful whether a simple way out of this difficulty exists.
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Horiba, Margareta. "The Visual Artist and the Law. By Shane Simpson. 2nd ed. Sidney: The Law Book Company Limited, 1989. Pp. xix, 311. A$36.00 (softcover)." International Journal of Legal Information 18, no. 2 (1990): 146. http://dx.doi.org/10.1017/s0731126500026731.
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Rebenne, H. E. "A review of: “ATOMIC LAYER EPITAXY” edited by T. Suntola and M. Simpson Blackie and Son Limited Glasgow and London 182 pages, hardcover, 1990." Materials and Manufacturing Processes 8, no. 4-5 (July 1993): 563–65. http://dx.doi.org/10.1080/10426919308934858.
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Climent, Eric, Juan Francisco Martinez-Blanch, Laura Llobregat, Beatriz Ruzafa-Costas, Miguel Ángel Carrión-Gutiérrez, Ana Ramírez-Boscá, David Prieto-Merino, et al. "Changes in Gut Microbiota Correlates with Response to Treatment with Probiotics in Patients with Atopic Dermatitis. A Post Hoc Analysis of a Clinical Trial." Microorganisms 9, no. 4 (April 15, 2021): 854. http://dx.doi.org/10.3390/microorganisms9040854.
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Atopic dermatitis (AD) is a chronic recurrent inflammatory skin disease with a high impact on the comfort of those who are affected and long-term treated with corticosteroids with limited efficacy and a high prevalence of relapses. Because of the limited effectiveness of these treatments, new strategies for recovery from AD lesions are continually being explored. In this article, we describe the gut microbiome changes achieved in a recently published clinical trial with the probiotic formulation Bifidobacterium animalis subsp. lactis CECT 8145, Bifidobacterium longum CECT 7347, and Lacticaseibacillus casei CECT 9104 (formerly Lactobacillus casei CECT 9104), showing a significant improvement in SCORAD (scoring atopic dermatitis) index in children (4–17 years) with AD (Clinicaltrials.gov identifier: NCT02585986). The present gut microbiome post hoc study showed no significant changes in diversity (Shannon and Simpson indexes) after probiotic consumption. In the probiotic group, genera Bacteroides, Ruminococcus, and Bifidobacterium significantly increased their levels while Faecalibacterium decreased, compared to the placebo group. Faecalibacterium showed the highest presence and significant positive correlation with AD severity (SCORAD index), whereas Abyssivirga, Bifidobacterium, and Lactococcus were inversely correlated. The results suggest that the consumption of the probiotic formulation here assayed modulates the gut microbiome with significant changes in genera Bacteroides and Faecalibacterium. In turn, the improvement in SCORAD correlates with a decrease in Faecalibacterium and an increase in Bifidobacterium, among others.
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Kelly, C., P. Hagan, M. Knight, J. Hodgson, A. J. G. Simpson, F. Hackett, H. A. Wilkins, and S. R. Smithers. "Surface and species-specific antigens ofSchistosoma haematobium." Parasitology 95, no. 2 (October 1987): 253–66. http://dx.doi.org/10.1017/s0031182000057711.
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SUMMARYOf the surface antigens identified by radio-iodination, two-dimensional gel analyses showed no similarities between those ofSchistosoma haematobiumandSchistosoma mansoni, thus providing a basis for the species specificity of these antigens described previously (Simpson, Knight, Hagan, Hodgson, Wilkins & Smithers (1985)Parasitology90, 499–508). The surface antigens ofS. haematobiumwere glycosylated and comprised an acidic polypeptide ofMr17000 as well as a complex set of polypeptides of approximate pI 6–7, which resolved in theMrrange 20000–30000. At least one of the lowerMrforms of this complex is also present in the adult worm. Limited cross-reaction was observed withS. mansoniinfection sera and this may be due to a shared carbohydrate epitope. In contrast, extensive cross-reaction was observed using sera from mice immunized withS. bovis.This pattern parallels the species-specificity of vaccine-induced immunity. Extensive cross-reaction was also observed within cell-free translation products of m-RNA from adult worms ofS. haematobiumandS. mansoniby use of heterologous human infection sera. The few antigens which were species-specific may represent surface antigens.
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Vonich, P. Trent, and Gregory J. Hakim. "Hurricane Kinetic Energy Spectra from In Situ Aircraft Observations." Journal of the Atmospheric Sciences 75, no. 8 (July 13, 2018): 2523–32. http://dx.doi.org/10.1175/jas-d-17-0270.1.
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Abstract Since the pioneering paper by Nastrom and Gage on aircraft-derived power spectra, significant progress has been made in understanding the wavenumber distribution of energy in Earth’s atmosphere and its implications for the intrinsic limits of weather forecasting. Improvements in tropical cyclone intensity predictions have lagged those of global weather forecasting, and limited intrinsic predictability may be partially responsible. In this study, we construct power spectra from aircraft data of over 1200 missions carried out by the National Oceanic and Atmospheric Administration (NOAA) and Air Force Reserve Command (AFRC) Hurricane Hunters. Each mission is parsed into distinct flight legs, and legs meeting a specified set of criteria are used for spectral analysis. Here, we produce power spectra composites for each category of the Saffir–Simpson scale, revealing a systematic relationship between spectral slope and storm intensity. Specifically, as storm intensity increases, we find that 1) spectral slope becomes steeper across scales from 10 to 160 km and 2) the transition zone where spectral slope begins to steepen shifts downscale.
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Draper, Roni Jo. "Every Teacher a Literacy Teacher? An Analysis of the Literacy-related Messages in Secondary Methods Textbooks." Journal of Literacy Research 34, no. 3 (September 2002): 357–84. http://dx.doi.org/10.1207/s15548430jlr3403_5.
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Every teacher a reading teacher has been the call of educators who have made their life work the promotion of reading and writing for middle and high school students (Gray, 1925; Herber, 1970; Ruddell, 1997; Vacca & Vacca, 2002). State departments of education in many states in the United States require secondary content-area teachers to complete course work in content-area reading and writing in order to obtain a teaching license (Romine, McKenna, & Robinson, 1996), seemingly to support this notion that every content-area teacher should also be a teacher of reading and writing. Although these requirements may be changing to accommodate other state requirements (Stewart & O'Brien, 2001), course work in content-area literacy remains common. Instructors with expertise in adolescent and content-area literacy have provided preservice courses to inform secondary teachers of methods to infuse literacy instruction with content instruction in ways that strengthen students' content-area learning and promote general literacy development. However, despite the slogans, the legislation, and the coursework, limited instruction in literacy occurs in secondary content-area classrooms (Eldridge & Muller, 1986, in Alvermann & Moore, 1991; Ratekin, Simpson, Alvermann, & Dishner, 1985).
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Nguyen, Nathalie T., Liisa L. Lyon, Gregory S. Moes, Kamran Sahrakar, and John L. Villano. "Clinical outcome of 1,968 cases of meningiomas from Kaiser Permanente Northern California." Journal of Clinical Oncology 31, no. 15_suppl (May 20, 2013): 2062. http://dx.doi.org/10.1200/jco.2013.31.15_suppl.2062.
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2062 Background: Meningioma is the most common primary brain tumor in the United States, but there is limited data on clinical outcomes. Methods: We performed descriptive and survival analysis of meningioma cases diagnosed 2001-2010 from the Kaiser Permanente Northern California Cancer Registry, which began inclusion of benign brain tumors in 2001. Datasets provided variables on gender, age at diagnosis, race, and vital status. Chart review extracted additional information on mortality, histology, imaging, tumor size, tumor site, and treatment. We used Kaplan Meier method to calculate overall survival (OS) and disease-free survival (DFS) and log-rank test to compare survival rates by variables. Cox proportional hazard models were used to analyze variables relative to endpoints. Results: 1968 cases in 1792 patients with meningioma were analyzed. 55% of cases had histological confirmation. 5- and 10-year OS and DFS for all groups were 76% & 61% and 89% & 82%. Disease progression and recurrence presented in 10% of cases at 10 years, resulting in 4% disease-specific mortality (DSM). Statistically significant prognostic factors of worse DFS were age >= 80, WHO grade 2-3, tumor size >= 18 mm, peritumoral edema on imaging, Simpson grades (SG) 4 or 5, and no surgery. Factors associated with significantly worse OS included age >= 60, male gender, tumor size >= 42 mm, peritumoral edema, SG 4 or 5, no histology and no treatment (NT). SG 1-3 groups provided statistically the highest OS and DFS. There was no significant difference in DFS or OS for definitive RT versus surgery and adjuvant RT groups. Definitive RT showed significantly better OS than NT (HR=0.46, 95% CI: 0.21-0.98). Cases with progression or recurrence had 51% DSM with 65% of deaths associated with lack of salvage therapy. Salvage RT provided better OS benefit compared to other salvage groups (HR=0.35, 95% CI: 0.14-0.91). Conclusions: We demonstrated favorable long-term outcome for meningiomas and confirmed the prognostic benefit of Simpson grading. We have identified additional adverse factors affecting outcome. While surgery remains standard, definitive RT demonstrates comparable outcome to cases not amenable to gross total resection. Salvage RT is effective, providing a survival benefit.
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Christodoulides, Ioannis, Jose Pedro Lavrador, Francesco Vergani, Ranjeev Bhangoo, Richard Gullan, and Keyoumars Ashkan. "Transformation of grade II to grade III rhabdoid-papillary meningioma: Is SRS the culprit?" Neuro-Oncology 21, Supplement_4 (October 2019): iv19. http://dx.doi.org/10.1093/neuonc/noz167.085.
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Abstract Objectives Meningiomas demonstrate specific genetic and epigenetic mutations, whose effect on recurrence and progression is still of limited understanding. Single-fraction stereotactic radiosurgery (SRS) is an established alternative treatment to surgical resection, proven to achieve excellent local disease control with minimal side effects. However, its effects on tumorigenesis and malignant transformation are still uncertain. The published estimated risk ranges from 0.04%-2.6% at 15 years. Design Case report Subjects Female patient referred to our neurosurgical service Methods Retrospective analysis of patient’s notes, histopathology reports, clinic letters, MDT decisions and imaging studies Results This report describes a case of a grade II parafalcine meningioma, that was initially resected with a Simpson 2 clearance, and upon recurrence, was managed with a single dose of SRS. More than 7 years later, the meningioma recurred, and due to its increasing size on follow-up imaging, it was re-resected. Histopathology revealed a grade III rhabdoid-papillary lesion, with local brain invasion. Conclusions To our knowledge, this was the first report to describe malignant transformation of a grade II to a grade III meningioma following SRS therapy to date. Therefore, considering the recent trend towards SRS-treatment for meningiomas, the treating team should always consider its potential effects on tumorigenesis.
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Qiao, Qi, Freek G. Bouwman, Marleen A. van Baak, Johan Renes, and Edwin C. M. Mariman. "Glucose Restriction Plus Refeeding in Vitro Induce Changes of the Human Adipocyte Secretome with an Impact on Complement Factors and Cathepsins." International Journal of Molecular Sciences 20, no. 16 (August 20, 2019): 4055. http://dx.doi.org/10.3390/ijms20164055.
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Adipose tissue is a major endocrine organ capable of secreting adipokines with a role in whole-body metabolism. Changes in the secretome profile during the development of obesity is suspected to contribute to the risk of health complications such as those associated with weight regain after weight loss. However, the number of studies on weight regain is limited and secretome changes during weight regain have hardly been investigated. In an attempt to generate leads for in vivo studies, we have subjected human Simpson Golabi Behmel Syndrome adipocytes to glucose restriction (GR) followed by refeeding (RF) as an in vitro surrogate for weight regain after weight loss. Using LC-MS/MS, we compared the secreted protein profile after GR plus RF with that of normal feeding (NF) to assess the consequences of GR plus RF. We identified 338 secreted proteins of which 49 were described for the first time as being secreted by adipocytes. In addition, comparison between NF and GR plus RF showed 39 differentially secreted proteins. Functional classification revealed GR plus RF-induced changes of enzymes for extracellular matrix modification, complement system factors, cathepsins, and several proteins related to Alzheimer’s disease. These observations can be used as clues to investigate metabolic consequences of weight regain, weight cycling or intermittent fasting.
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Lethbridge, Mark, Keith W. Saalfeld, and Glenn P. Edwards. "Measured reductions in the density of camels under the Australian Feral Camel Management Project." Rangeland Journal 38, no. 2 (2016): 173. http://dx.doi.org/10.1071/rj15106.
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In this paper we provide a coarse comparison between camel density estimates derived from aerial surveys conducted during the early and latter stages of the Australian Feral Camel Management Project, considering the number of camels removed between the surveys as a result of management intervention across three large and distinct geographic zones. Overall, despite the assumptions made during our analyses and possible errors associated with these, the post-aerial surveys in all three zones show a significant population decline compared with the corresponding pre-aerial surveys. The observed population decline in two zones (the Pilbara and that centred on the South Australia-Western Australia-Northern Territory border junction) were broadly consistent with the number of camels removed in each zone between aerial surveys. The population decline detected in the third zone (the Simpson Desert) was much greater than the known removals and there appeared to be another factor involved, possibly drought-induced natural mortality. We raise a number of concerns about making this type of comparison, including the limitations of working with a highly mobile species distributed across a broad landscape and the low number of aerial surveys available for this type of comparison due to a limited project monitoring budget.
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Hook, Ernest B., and Ronald R. Regal. "Conceptus viability, malformation, and suspect mutagens or teratogens in humans. The Yule-Simpson paradox and implications for inferences of causality in studies of mutagenicity or teratogenicity limited to human livebirths." Teratology 43, no. 1 (January 1991): 53–59. http://dx.doi.org/10.1002/tera.1420430107.
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Chiu, Chun-Huo, and Anne Chao. "Estimating and comparing microbial diversity in the presence of sequencing errors." PeerJ 4 (February 1, 2016): e1634. http://dx.doi.org/10.7717/peerj.1634.
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Estimating and comparing microbial diversity are statistically challenging due to limited sampling and possible sequencing errors for low-frequency counts, producing spurious singletons. The inflated singleton count seriously affects statistical analysis and inferences about microbial diversity. Previous statistical approaches to tackle the sequencing errors generally require different parametric assumptions about the sampling model or about the functional form of frequency counts. Different parametric assumptions may lead to drastically different diversity estimates. We focus on nonparametric methods which are universally valid for all parametric assumptions and can be used to compare diversity across communities. We develop here a nonparametric estimator of the true singleton count to replace the spurious singleton count in all methods/approaches. Our estimator of the true singleton count is in terms of the frequency counts of doubletons, tripletons and quadrupletons, provided these three frequency counts are reliable. To quantify microbial alpha diversity for an individual community, we adopt the measure of Hill numbers (effective number of taxa) under a nonparametric framework. Hill numbers, parameterized by an orderqthat determines the measures’ emphasis on rare or common species, include taxa richness (q= 0), Shannon diversity (q= 1, the exponential of Shannon entropy), and Simpson diversity (q= 2, the inverse of Simpson index). A diversity profile which depicts the Hill number as a function of orderqconveys all information contained in a taxa abundance distribution. Based on the estimated singleton count and the original non-singleton frequency counts, two statistical approaches (non-asymptotic and asymptotic) are developed to compare microbial diversity for multiple communities. (1) A non-asymptotic approach refers to the comparison of estimated diversities of standardized samples with a common finite sample size or sample completeness. This approach aims to compare diversity estimates for equally-large or equally-complete samples; it is based on the seamless rarefaction and extrapolation sampling curves of Hill numbers, specifically forq= 0, 1 and 2. (2) An asymptotic approach refers to the comparison of the estimated asymptotic diversity profiles. That is, this approach compares the estimated profiles for complete samples or samples whose size tends to be sufficiently large. It is based on statistical estimation of the true Hill number of any orderq≥ 0. In the two approaches, replacing the spurious singleton count by our estimated count, we can greatly remove the positive biases associated with diversity estimates due to spurious singletons and also make fair comparisons across microbial communities, as illustrated in our simulation results and in applying our method to analyze sequencing data from viral metagenomes.
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Jirka, Gerhard H., and Masamitsu Arita. "Density currents or density wedges: boundary-layer influence and control methods." Journal of Fluid Mechanics 177 (April 1987): 187–206. http://dx.doi.org/10.1017/s0022112087000910.
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Density currents and density wedges are two observed manifestations of interactions between an ambient flow and a horizontal buoyant intrusion. In a density current the buoyant pressure force is primarily balanced by the local form drag of the current head which has a blunt shape and abrupt depth change. In a density wedge a distributed interfacial drag is the primary balancing force, leading to a stretched-out shape and long-distance intrusions. A perturbation analysis of the approach flow to the inclined front of a density current shows that slight momentum changes caused by viscous effects in the ambient flow determine which of these two flow types is established. In a uniform ambient channel flow, any momentum deficit relative to the inviscid case will lead to a local flattening of the front and ultimate breakdown into a density wedge. On the other hand, a momentum surplus will support a steady-state density current. Several exploratory experiments on control of the ambient boundary layer through local non-uniformities were performed with the objective of achieving stable density-current forms with limited intrusion lengths. These methods include a small step, a barrier and suction and are applied for intrusions at either the bottom or surface of an ambient water flow. In all cases, good agreement is found with the force balances predicted by Benjamin's (1968) theory and its extension by Britter & Simpson (1978) which accounts for entrainment in the wake zone of the head.
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Rivenes, Shannon M., Mark B. Lewin, Stephen A. Stayer, Sabrina T. Bent, Heather M. Schoenig, E. Dean McKenzie, Charles D. Fraser, and Dean B. Andropoulos. "Cardiovascular Effects of Sevoflurane, Isoflurane, Halothane, and Fentanyl–Midazolam in Children with Congenital Heart Disease." Anesthesiology 94, no. 2 (February 1, 2001): 223–29. http://dx.doi.org/10.1097/00000542-200102000-00010.
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Background The cardiovascular effects of halogenated anesthetic agents in children with normal hearts have been studied, but data in children with cardiac disease are limited. This study compared the effects of halothane, isoflurane, sevoflurane, and fentanyl-midazolam on systemic and pulmonary hemodynamics and myocardial contractility in patients with congenital heart disease. Methods Fifty-four patients younger than age 14 scheduled to undergo congenital heart surgery were randomized to receive halothane, sevoflurane, isoflurane, or fentanyl-midazolam. Cardiovascular and echocardiographic data were recorded at baseline and at randomly ordered 1 and 1.5 minimum alveolar concentrations, or predicted equivalent fentanyl-midazolam plasma concentrations. The shortening fraction and ejection fraction (using the modified Simpson rule) were calculated. Cardiac index was assessed by the velocity-time integral method. Results Halothane caused a significant decrease in mean arterial pressure, ejection fraction, and cardiac index, preserving only heart rate at baseline levels. Fentanyl-midazolam in combination caused a significant decrease in cardiac index secondary to a decrease in heart rate; contractility was maintained. Sevoflurane maintained cardiac index and heart rate and had less profound hypotensive and negative inotropic effects than halothane. Isoflurane preserved both cardiac index and ejection fraction, had less suppression of mean arterial pressure than halothane, and increased heart rate. Conclusions Isoflurane and sevoflurane preserved cardiac index, and isoflurane and fentanyl-midazolam preserved myocardial contractility at baseline levels in this group of patients with congenital heart disease. Halothane depressed cardiac index and myocardial contractility.
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Polain, Katherine, Oliver Knox, Brian Wilson, and Lily Pereg. "Subsoil Microbial Diversity and Stability in Rotational Cotton Systems." Soil Systems 4, no. 3 (July 25, 2020): 44. http://dx.doi.org/10.3390/soilsystems4030044.
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Microbial diversity has been well documented for the top 0–0.30 m of agricultural soils. However, spatio-temporal research into subsoil microbial diversity and the effects of agricultural management remains limited. Soil type may influence subsoil microbial diversity, particularly Vertosols. These soils lack distinct horizons and are known to facilitate the downward movement of organic matter, potentially supporting subsoil microbiota, removed from the crop root system (i.e., bulk soils). Our research used the MiSeq Illumina Platform to investigate microbial diversity down the profile of an agricultural Australian Vertosol to 1.0 m in bulk soils, as influenced by crop system (continuous cotton and cotton–maize) and sample time (pre- and in-crop samples collected over two seasons). Overall, both alpha- (Chao1, Gini–Simpson Diversity and Evenness indices) and beta-diversity (nMDS and Sørensen’s Index of Similarity) metrics indicated that both bacterial (16S) diversity and fungal (ITS) diversity decreased with increasing soil depth. The addition of a maize rotation did not significantly influence alpha-diversity metrics until 0.70–1.0 m depth in the soil, where bacterial diversity was significantly higher in this system, with beta-diversity measures indicating this is likely due to root system differences influencing dissolved organic carbon. Sample time did not significantly affect bacterial or fungal diversity over the two seasons, regardless of the crop type and status (i.e., crop in ground and post crop). The relatively stable subsoil fungal and overall microbial diversity in bulk soils over two crop seasons suggests that these microbiota have developed a tolerance to prolonged agricultural management.
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Wong, Wendy S. W., Priya Sabu, Varsha Deopujari, Shira Levy, Ankit A. Shah, Nicole Clemency, Marina Provenzano, et al. "Prenatal and Peripartum Exposure to Antibiotics and Cesarean Section Delivery Are Associated with Differences in Diversity and Composition of the Infant Meconium Microbiome." Microorganisms 8, no. 2 (January 27, 2020): 179. http://dx.doi.org/10.3390/microorganisms8020179.
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The meconium microbiome may provide insight into intrauterine and peripartum exposures and the very earliest intestinal pioneering microbes. Prenatal antibiotics have been associated with later obesity in children, which is thought to be driven by microbiome dependent mechanisms. However, there is little data regarding associations of prenatal or peripartum antibiotic exposure, with or without cesarean section (CS), with the features of the meconium microbiome. In this study, 16S ribosomal RNA gene sequencing was performed on bacterial DNA of meconium samples from 105 infants in a birth cohort study. After multivariable adjustment, delivery mode (p = 0.044), prenatal antibiotic use (p = 0.005) and peripartum antibiotic use (p < 0.001) were associated with beta diversity of the infant meconium microbiome. CS (vs. vaginal delivery) and peripartum antibiotics were also associated with greater alpha diversity of the meconium microbiome (Shannon and Simpson, p < 0.05). Meconium from infants born by CS (vs. vaginal delivery) had lower relative abundance of the genus Escherichia (p < 0.001). Prenatal antibiotic use and peripartum antibiotic use (both in the overall analytic sample and when restricting to vaginally delivered infants) were associated with differential abundance of several bacterial taxa in the meconium. Bacterial taxa in the meconium microbiome were also differentially associated with infant excess weight at 12 months of age, however, sample size was limited for this comparison. In conclusion, prenatal and peripartum antibiotic use along with CS delivery were associated with differences in the diversity and composition of the meconium microbiome. Whether or not these differences in the meconium microbiome portend risk for long-term health outcomes warrants further exploration.
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Havelock, Rohan. "THE “UNITARY EXERCISE” OF CONTRACTUAL INTERPRETATION." Cambridge Law Journal 76, no. 3 (November 2017): 486–89. http://dx.doi.org/10.1017/s0008197317000745.
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LORD Hoffmann's famous “restatement” of the principles of contractual interpretation in Investors Compensation Scheme v West Bromwich Building Society [1998] 1 W.L.R. 896, 912–13, was heralded as a “quiet revolution” (McLauchlan (2000) 19 N.Z.U.L.R. 147, at 148) in that it appeared to overthrow the legalistic approach of the past. That approach, often associated with the “plain meaning rule” (Bank of New Zealand v Simpson [1990] A.C. 182 (PC), 189) involved giving effect to the expressed meaning of the text, which (limited exceptions aside) could not be contradicted by the relevant background (or matrix of fact). By contrast, the approach in ICS mandated the Court to search for the apparently intended meaning by consulting the relevant and admissible background in all cases. The ICS approach rapidly became dominant, and indeed orthodox, across multiple jurisdictions. However, in a series of judgments commencing with Re Sigma Finance Corporation [2009] UKSC 2; [2010] 1 All E.R. 571, the Supreme Court of the United Kingdom has gradually moved away from the approach in ICS (albeit without expressly overruling it) and emphasised the importance of giving effect to the natural and ordinary meaning of the words used, in combination with other factors (see especially Marley v Rawlings [2014] UKSC 2; [2014] 2 W.L.R. 213, at [18]–[19]; Arnold v Britton [2015] UKSC 36; [2015] A.C. 1619, at [14]–[23]). This return to a more traditional approach to interpretation vindicates sustained criticism of the validity of the ICS approach in principle and practice (see e.g. Staughton [1999] C.L.J. 303; Berg (2006) 122 L.Q.R. 354; Buxton [2010] C.L.J. 253).
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Mooney, Michael A., Mohammad Abolfotoh, Wenya Linda Bi, Daryoush Tavanaiepour, Rami O. Almefty, Hischam Bassiouni, Svetlana Pravdenkova, Ian F. Dunn, and Ossama Al-Mefty. "Is Falcine Meningioma a Diffuse Disease of the Falx? Case Series and Analysis of a “Grade Zero” Resection." Neurosurgery 87, no. 5 (April 15, 2020): 900–909. http://dx.doi.org/10.1093/neuros/nyaa038.
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Abstract BACKGROUND Falcine meningiomas have unique characteristics including their high rates of recurrence, association with high grade pathology, increased male prevalence, and potential for diffuse involvement of the falx. OBJECTIVE To address these issues in a substantial series of falcine meningiomas and report on the impact of extent of resection for this distinct meningioma entity. METHODS Retrospective analysis of characteristics and outcomes of 59 falcine meningioma patients who underwent surgery with the senior author. A “Grade Zero” category was used when an additional resection margin of 2 to 3 cm from the tumor insertion was achieved. RESULTS For de novo falcine meningiomas, gross total resection (GTR) was associated with significantly decreased recurrence incidence compared with subtotal resection (P ≤ .0001). For recurrent falcine meningiomas, median progression-free survival (PFS) was significantly improved for GTR cases (37 mo vs 12 mo; P = .017, hazard ratio (HR) .243 (.077-.774)). “Grade Zero” resection demonstrated excellent durability for both de novo and recurrent cases, and PFS was significantly improved with “Grade Zero” resection for recurrent cases (P = .003, HR 1.544 (1.156-2.062)). The PFS benefit of “Grade Zero” resection did not achieve statistical significance over Simpson grade 1 during the limited follow-up period (mean 2.8 yr) for these groups. CONCLUSION The recurrence of falcine meningiomas is related to the diffuse presence of tumor between the leaflets of the falx. Increased extent of resection including, when possible, a clear margin of falx surrounding the tumor base was associated with the best long-term outcomes in our series, particularly for recurrent tumors.
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Kockova, Radka, Jarmila Svatunkova, Jiri Novotny, Lucie Hejnova, Bohuslav Ostadal, and David Sedmera. "Heart rate changes mediate the embryotoxic effect of antiarrhythmic drugs in the chick embryo." American Journal of Physiology-Heart and Circulatory Physiology 304, no. 6 (March 15, 2013): H895—H902. http://dx.doi.org/10.1152/ajpheart.00679.2012.
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A significant increase in cardiovascular medication use during pregnancy occurred in recent years. Only limited evidence on safety profiles is available, and little is known about the mechanisms of adverse effect on the fetus. We hypothesized that drug-induced bradycardia is the leading mechanism of developmental toxicity. Embryotoxicity was tested in ovo after administration of various doses of metoprolol, carvedilol, or ivabradine. Embryonic day (ED) 4 and 8 chick embryos were studied by video microscopy and ultrasound biomicroscopy ex ovo after intraamniotic injection of the drug for a period of 30 min. Stroke volume was calculated by the Simpson method and prolate ellipsoid formula. Significant dose-dependent mortality was achieved in embryos injected with carvedilol and ivabradine. In ED4 embryos, metoprolol, carvedilol, and ivabradine reduced the heart rate by 33%, 27%, and 55%, respectively, compared with controls (6%). In ED8 embryos this effect was more pronounced with a heart rate reduction by 71%, 54%, and 53%, respectively (controls, 36%). Cardiac output decreased in all tested groups but only proved significant in the metoprolol group in ED8 embryos. The number of β-adrenergic receptors showed a downward tendency during embryonic development. A negative chronotropic effect of metoprolol, carvedilol, and ivabradine was increasingly pronounced with embryonic maturity despite a downward trend in the number of β-adrenergic receptors. This effect was associated with reduced cardiac output in chick embryos, probably leading to premature death. Although standard doses of these drugs appear relatively safe, high doses have a potentially adverse effect on the fetus through reduced heart rate.
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Bukowy-Bieryllo, Zuzanna, Alicja Rabiasz, Maciej Dabrowski, Andrzej Pogorzelski, Alina Wojda, Hanna Dmenska, Katarzyna Grzela, Jakub Sroczynski, Michal Witt, and Ewa Zietkiewicz. "Truncating mutations in exons 20 and 21 of OFD1 can cause primary ciliary dyskinesia without associated syndromic symptoms." Journal of Medical Genetics 56, no. 11 (July 31, 2019): 769–77. http://dx.doi.org/10.1136/jmedgenet-2018-105918.
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BackgroundPrimary ciliary dyskinesia (PCD) is a motile ciliopathy, whose symptoms include airway infections, male infertility and situs inversus. Apart from the typical forms of PCD, rare syndromic PCD forms exist. Mutations of the X-linked OFD1 gene cause several syndromic ciliopathies, including oral-facial-digital syndrome type 1, Joubert syndrome type 10 (JBTS10), and Simpson-Golabi-Behmel syndrome type 2, the latter causing the X-linked syndromic form of PCD. Neurological and skeletal symptoms are characteristic for these syndromes, with their severity depending on the location of the mutation within the gene.ObjectivesTo elucidate the role of motile cilia defects in the respiratory phenotype of PCD patients with C-terminal OFD1 mutations.MethodsWhole-exome sequencing in a group of 120 Polish PCD patients, mutation screening of the OFD1 coding sequence, analysis of motile cilia, and magnetic resonance brain imaging.ResultsFour novel hemizygous OFD1 mutations, in exons 20 and 21, were found in men with a typical PCD presentation but without severe neurological, skeletal or renal symptoms characteristic for other OFD1-related syndromes. Magnetic resonance brain imaging in two patients did not show a molar tooth sign typical for JBTS10. Cilia in the respiratory epithelium were sparse, unusually long and displayed a defective motility pattern.ConclusionConsistent with the literature, truncations of the C-terminal part of OFD1 (exons 16–22) almost invariably cause a respiratory phenotype (due to motile cilia defects) while their impact on the primary cilia function is limited. We suggest that exons 20–21 should be included in the panel for regular mutation screening in PCD.
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Mair, Richard, Kevin Morris, Ian Scott, and Thomas A. Carroll. "Radiotherapy for atypical meningiomas." Journal of Neurosurgery 115, no. 4 (October 2011): 811–19. http://dx.doi.org/10.3171/2011.5.jns11112.
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Object The role of postoperative radiotherapy in patients undergoing first-time resection of WHO Grade II meningioma remains unclear as reflected by varied practices in published clinical studies and national professional surveys. Much of the relevant literature is based on pre-2000 WHO grading criteria for atypical meningiomas. Authors in this study set out to explore the role of postoperative radiotherapy in patients undergoing first-time surgery for WHO Grade II meningiomas diagnosed using revised WHO 2000 criteria, against a background of otherwise limited published literature on this issue. Methods The authors retrospectively collected data on 114 consecutive patients who underwent first-time resection of WHO Grade II atypical meningiomas diagnosed using 2000 WHO criteria, and who variably underwent postoperative radiotherapy according to individual surgeon practices. Outcomes, including radiological recurrence, were submitted to Kaplan-Meier and Cox regression analyses. Results Postoperative radiotherapy demonstrated a significant benefit only when patients who had undergone gross-total tumor resection and those who had undergone subtotal resection along with postoperative radiosurgery to the tumor remnant were excluded from analysis. Conclusions The authors have performed the largest study in the literature to examine the use of radiotherapy for WHO Grade II, atypical, meningiomas following a first-time resection. They suggest that radiotherapy is not appropriate after first-time resection of those lesions in which a gross-total resection (Simpson Grade 1 or 2) has been achieved. They also advise that any tumor remnant radiologically demonstrated on postoperative imaging should be treated with radiosurgery and that postoperative radiotherapy after a first-time resection should be reserved for tumor remnants too large for radiosurgery and for which a second staged operation is not planned.
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Quiñones-Hinojosa, Alfredo, Tania Kaprealian, Kaisorn L. Chaichana, Nader Sanai, Andrew T. Parsa, Mitchel S. Berger, and Michael W. McDermott. "Pre-Operative Factors Affecting Resectability of Giant Intracranial Meningiomas." Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques 36, no. 5 (September 2009): 623–30. http://dx.doi.org/10.1017/s0317167100008143.
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Objective:Larger intracranial tumors require extended operating times and may be associated with increased perioperative complications. There are few reports describing the experience of resecting large meningiomas ≥5cm in a variety of locations. As a group, it remains largely unknown whether these relatively rare lesions are amenable to radical resection, and what factors influence their resectability.Methods:Sixty-seven patients undergoing surgery for a large intracranial meningioma (≥5cm in the longest dimension) between 1998 and 2004 were retrospectively reviewed. The surgeries were performed at a single institution University of California at San Francisco. Predictors of resectability were assessed via multivariate logistical regression analysis.Results:Thirty-nine (58%) patients underwent gross total resection (GTR) (Simpson grades I/II). There were no cases of perioperative mortality. At last follow-up, symptoms improved in 39 (58%) patients, remained unchanged in 20 (30%), and were aggravated in 8 (12%). In the multivariate model for all large meningiomas, age>45 years [OR(95%CI);0.127 (0.026-0.616),p=0.01] and superior sagittal sinus involvement [OR(95%CI);0.160 (0.026-0.976),p=0.05] were negative predictors of GTR, while preoperative embolization [OR(95%CI);8.087(1.719-38.044),p=0.008] was positively associated with GTR. For only supratentorial meningiomas, superior sagittal sinus involvement [OR (95%CI);0.077 (0.010-0.571),p=0.01] and preoperative embolization [OR(95%CI);10.492(1.961-56.135),p=0.006] were independently associated with GTR.Conclusions:This study evaluated a subset of large intracranial meningiomas ≥5cm. The results indicate that GTR can be achieved in the majority of cases with limited morbidity and mortality, where symptoms will likely improve and recurrences seldom occur. This study may provide useful insights for patients undergoing surgery for large intracranial meningiomas.
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Anderson, Anna J., Ruth Andrew, Natalie Z. Homer, Gregory C. Jones, Kenneth Smith, Dawn E. Livingstone, Brian R. Walker, and Roland H. Stimson. "Metformin Increases Cortisol Regeneration by 11βHSD1 in Obese Men With and Without Type 2 Diabetes Mellitus." Journal of Clinical Endocrinology & Metabolism 101, no. 10 (July 26, 2016): 3787–93. http://dx.doi.org/10.1210/jc.2016-2069.
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Context: The mechanism of action of metformin remains unclear. Given the regulation of the cortisol-regenerating enzyme 11βhydroxysteroid dehydrogenase 1 (11βHSD1) by insulin and the limited efficacy of selective 11βHSD1 inhibitors to lower blood glucose when co-prescribed with metformin, we hypothesized that metformin reduces 11βHSD1 activity. Objective: To determine whether metformin regulates 11βHSD1 activity in vivo in obese men with and without type 2 diabetes mellitus. Design: Double-blind, randomized, placebo-controlled, crossover study. Setting: A hospital clinical research facility. Participants: Eight obese nondiabetic (OND) men and eight obese men with type 2 diabetes (ODM). Intervention: Participants received 28 days of metformin (1 g twice daily), placebo, or (in the ODM group) gliclazide (80 mg twice daily) in random order. A deuterated cortisol infusion at the end of each phase measured cortisol regeneration by 11βHSD1. Oral cortisone was given to measure hepatic 11βHSD1 activity in the ODM group. The effect of metformin on 11βHSD1 was also assessed in human hepatocytes and Simpson-Golabi-Behmel syndrome adipocytes. Main Outcome Measures: The effect of metformin on whole-body and hepatic 11βHSD1 activity. Results: Whole-body 11βHSD1 activity was approximately 25% higher in the ODM group than the OND group. Metformin increased whole-body cortisol regeneration by 11βHSD1 in both groups compared with placebo and gliclazide and tended to increase hepatic 11βHSD1 activity. In vitro, metformin did not increase 11βHSD1 activity in hepatocytes or adipocytes. Conclusions: Metformin increases whole-body cortisol generation by 11βHSD1 probably through an indirect mechanism, potentially offsetting other metabolic benefits of metformin. Co-prescription with metformin should provide a greater target for selective 11βHSD1 inhibitors.
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Simpson, Fiona, Andrew A. Peden, Lina Christopoulou, and Margaret S. Robinson. "Characterization of the Adaptor-related Protein Complex, AP-3." Journal of Cell Biology 137, no. 4 (May 19, 1997): 835–45. http://dx.doi.org/10.1083/jcb.137.4.835.
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We have recently shown that two proteins related to two of the adaptor subunits of clathrincoated vesicles, p47 (μ3) and β-NAP (β3B), are part of an adaptor-like complex not associated with clathrin (Simpson, F., N.A. Bright, M.A. West, L.S. Newman, R.B. Darnell, and M.S. Robinson, 1996. J. Cell Biol. 133:749–760). In the present study we have searched the EST database and have identified, cloned, and sequenced a ubiquitously expressed homologue of β-NAP, β3A, as well as homologues of the α/γ and σ adaptor subunits, δ and σ3, which are also ubiquitously expressed. Antibodies raised against recombinant δ and σ3 show that they are the other two subunits of the adaptor-like complex. We are calling this complex AP-3, a name that has also been used for the neuronalspecific phosphoprotein AP180, but we feel that it is a more appropriate designation for an adaptor-related heterotetramer. Immunofluorescence using anti-δ antibodies reveals that the AP-3 complex is associated with the Golgi region of the cell as well as with more peripheral structures. These peripheral structures show only limited colocalization with endosomal markers and may correspond to a postTGN biosynthetic compartment. The δ subunit is closely related to the protein product of the Drosophila garnet gene, which when mutated results in reduced pigmentation of the eyes and other tissues. Because pigment granules are believed to be similar to lysosomes, this suggests either that the AP-3 complex may be directly involved in trafficking to lysosomes or alternatively that it may be involved in another pathway, but that missorting in that pathway may indirectly lead to defects in pigment granules.
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Yin, You, Qiuli Li, and Haitao Du. "Near-natural transformation of Pinus tabuliformis better improve soil nutrients and soil microbial community." PeerJ 9 (September 23, 2021): e12098. http://dx.doi.org/10.7717/peerj.12098.
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Pinus tabulaeformis plantations have been established around northern China to restore degraded land and provide timber or fuelwood. In recent years, widely distributed monoculture P. tabulaeformis forests have been transformed into mixed forests due to various ecological problems. However, the current research on the influence of near-natural transformation of P. tabulaeformis on soil microbial diversity and community composition remains limited. Therefore, we examined the effect of forest conversion from monoculture Pinus tabuliformis (PT) to P. tabuliformis-Armeniaca vulgaris (PTAU), P. tabuliformis - Robinia pseudoacacia (PTRP), P. tabuliformis - Vitex negundo L. var. heterophylla (PTVN) forests on soil microbial community diversity and composition. The results indicated that compared to PT, PTAU, PTVN, and PTRP could enhance the soil pH, TC, TN, AN, and AK in different degrees, the most obvious in PTAU. Near-natural transformation of P. tabuliformis could improve soil bacterial Pielou_e index, and Simpson index, as well as soil fungal Chao1 index. Proteobacteria and Ascomycota were the dominant soil microbial community at the phylum level. What’s more, both soil bacterial and fungal community among PT, PTAU, PTRP and PTVN showed clear different, and PTAU obviously altered the soil microbial community structure. Proteobacteria was the predominant group in PT, while, Gemmatimonadetes enriched in PTVN. Ascomycota was the predominant group in PTAU, while, Basidiomycota was the predominant group in PTRP. Near-natural transformation of P. tabuliformis could change soil microbial community via altering soil characteristics. In brief, our research results revealed the influence of tree composition and soil nutrient availability on soil microbial diversity and composition, and provided management guidance for introduction soil microbial community in forest protection and management.
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Terpolilli, Nicole Angela, Moritz Ueberschaer, Maximilian Niyazi, Christoph Hintschich, Rupert Egensperger, Alexander Muacevic, Niklas Thon, Jörg-Christian Tonn, and Christian Schichor. "Long-term outcome in orbital meningiomas: progression-free survival after targeted resection combined with early or postponed postoperative radiotherapy." Journal of Neurosurgery 133, no. 2 (August 2020): 302–12. http://dx.doi.org/10.3171/2019.3.jns181760.
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OBJECTIVEIn meningiomas involving the orbit and optic canal, surgery is the mainstay of therapy. However, radical resection is often limited to avoid functional damage, so multidisciplinary treatment concepts are implemented. Data on the timing and value of early postoperative radiotherapy (PORT) are scarce. This retrospective study analyzes outcomes in patients who underwent targeted resection alone or in combination with early PORT.METHODSPatients undergoing resection of orbit-associated WHO grade I meningiomas from January 1999 to December 2013 who presented to the authors’ department at least twice for follow-up were included. Clinical and radiological findings were analyzed retrospectively. Patients were stratified into two cohorts: follow-up with MRI scans at regular intervals, i.e., the watch and wait (W&W) group, and a PORT group receiving PORT within 6 months after surgery in addition to MRI follow-up. Patients in the W&W group were scheduled for treatment when tumor progression was detected by imaging.RESULTSOne hundred twenty-two patients were included. The mean follow-up was 70 months. The most common symptoms at presentation were visual disturbances; 87.7% of patients received Simpson grade II–III targeted partial resection. Twenty-three patients received PORT, and 99 patients were regularly observed with MRI scans (W&W group). Tumor recurrence/progression occurred significantly later (76.3 vs 40.7 months) and less frequently in the PORT group (13%) than in the W&W group (46.5%). Cases of recurrence were diagnosed an average of 39 months after initial surgery in both groups. PORT patients demonstrated significantly less visual impairment at last follow-up.CONCLUSIONSThese results indicate that receiving PORT early after targeted partial resection might help to postpone tumor recurrence and the need for additional treatment, while preserving or even improving visual outcome.
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Wang, Xiuling, Shunjie Liu, Mingjie Chen, Changxia Yu, Yan Zhao, Huanling Yang, Lei Zha, and Zhengpeng Li. "Low Temperature (15 °C) Reduces Bacterial Diversity and Prolongs the Preservation Time of Volvariella volvacea." Microorganisms 7, no. 10 (October 20, 2019): 475. http://dx.doi.org/10.3390/microorganisms7100475.
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Straw mushroom (Volvariella volvacea) is the most commonly cultivated edible fungus in the world, but the challenges associated with the preservation have limited its marketability. Microbiology, especially bacteria, play a key role in the deterioration of food, this study aimed to reveal the succession of the bacterial community on the surfaces of V. volvacea fruit bodies under different temperature conditions. We amplified 16S rRNA genes of V4 regions, obtained the bacterial species information by using high-throughput sequencing technology, and analyzed the effects of environmental temperature and preservation time on bacterial communities. The relative abundances of Firmicutes, Bacilli, and Bacillales increased significantly when straw mushrooms began to rot. Furthermore, the relative abundances of Paenibacillus, Lysinibacillus and Solibacillus, which belong to Bacillales, increased with the decay of straw mushroom. The Shannon and Simpson indices of V. volvacea stored at 30 °C were significantly higher than those of V. volvacea stored at 15 °C, which indicates that a high temperature contributes to the improvement in the species diversity. According to the linear discriminant analysis (LDA) effect size (LEfSe) results, the number of biomarkers in the 30 °C group (32, 42.11%) was significantly higher than that in the 15 °C group (17, 22.37%), indicating that a high temperature has a clustering effect on some bacterial communities. A Spearman correlation analysis showed that Pseudomonas, Stenotrophomonas and Solibacillus promoted the decay of straw mushroom. In conclusion, a high temperature increases the bacterial diversity on the straw mushroom surfaces and has a clustering effect on the bacterial communities. The bacterial community consisting of Firmicutes, Bacilli, Bacillales, Paenibacillus, Lysinibacillus, Pseudomonas, Stenotrophomonas and Solibacillus could promote the decay of straw mushroom, so new preservation materials research can focus on inhibiting anaerobic and decay-causing bacteria to prolong preservation time.
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Chi, John H., Andrew T. Parsa, Mitchel S. Berger, Sandeep Kunwar, and Michael W. McDermott. "Extended Bifrontal Craniotomy for Midline Anterior Fossa Meningiomas:Minimization of Retraction-Related Edema and Surgical Outcomes." Operative Neurosurgery 59, suppl_4 (January 2006): ONS—426—ONS—434. http://dx.doi.org/10.1227/01.neu.0000223508.60923.91.
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Abstract OBJECTIVE: Meningiomas of the anterior cranial base can be approached with a variety of techniques. The extended bifrontal approach is often thought to be associated with increased morbidity because of the need for extensive removal of the bone and longer surgical times. The authors have attempted to quantitate retraction-related edema occurring after surgery to determine whether the extra bone removal limits retraction and reduces the chance of brain injury. METHODS: Charts were reviewed for patients who underwent extended bifrontal craniotomies performed for meningiomas at the University of California, San Francisco, between 1997 and 2005. Magnetic resonance imaging scans obtained before and after surgery were reviewed for brain edema as indicated by fluid-attenuated inversion recovery/T2 abnormality and grouped into four categories: A, no edema; B, edema restricted to the gyrus rectus; C, edema beyond the gyrus rectus; and D, extensive bifrontal edema. RESULTS: Forty-five patients were identified. Fifty-four percent of patients had tumors with a diameter of more than 4 cm. Simpson Grade 2 or 3 resection was achieved in 82% of patients, and the average operative time was 12.3 hours. Vision outcome was favorable in 74% of patients. Extent of fluid-attenuated inversion recovery abnormality remained unchanged in 87.5%, with 91% of patients in categories A or B edema remaining in those categories after surgery. There were no infections and there were two cerebrospinal fluid leaks. CONCLUSION: The extended bifrontal approach is a safe surgical procedure with limited morbidity that the authors think: 1) prevents secondary brain injury from excessive retraction; 2) offers great flexibility of view for the surgeon; and 3) should be considered the preferred approach compared with the standard bifrontal craniotomy for large tumors of the anterior cranial base.
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Li, Weike, Xiaodong Liu, and Shukui Niu. "Differential responses of the acidobacterial community in the topsoil and subsoil to fire disturbance in Pinus tabulaeformis stands." PeerJ 7 (December 11, 2019): e8047. http://dx.doi.org/10.7717/peerj.8047.
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Acidobacteria is found to be dominant and abundant in forest soil, and performs specific ecological functions (such as cellulose decomposition and photosynthetic capacity, etc.). However, relative limited is known about its changing patterns after a fire interruption. In this study, the response of soil Acidobacteria to a wildfire disturbance was investigated using the Illumina MiSeq sequencing system. The research area was classified by different severities of fire damage (high, moderate, and low severity, and an unburnt area), and samples were collected from various soil layers (0–10 cm as topsoil; 10–20 cm as subsoil). We obtained a total of 986,036 sequence reads; 31.77% of them belonged to Acidobacteria. Overall, 18 different Acidobacteria subgroups were detected, with subgroups 4, 6, 1, 3, and 2 the most abundant, accounting for 31.55%, 30.84%, 17.42%, 6.02%, and 5.81% of acidobacterial sequences across all samples, respectively. Although no significant differences in acidobacterial diversity were found in the same soil layer across different fire severities, we observed significantly lower numbers of reads, but higher Shannon and Simpson indices, in the topsoil of the high-severity fire area than in the subsoil. Non-metric multidimensional scaling (NMDS) analysis and permutational multivariate analysis of variance (PERMANOVA) also revealed significant differences in the acidobacterial community structure between the two soil layers. Soil pH, total nitrogen, NH4+-N, the Shannon index of understory vegetation and canopy density were the major drivers for acidobacterial community structure in the topsoil, while soil pH and organic matter were significant factors in the subsoil. A variance partitioning analysis (VPA) showed that edaphic factors explained the highest variation both in the topsoil (15.6%) and subsoil (56.3%). However, there are large gaps in the understanding of this field of research that still need to be explored in future studies.
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Dickman, Christopher R., Adele S. Haythornthwaite, Gayle H. McNaught, Paul S. Mahon, Bobby Tamayo, and Mike Letnic. "Population dynamics of three species of dasyurid marsupials in arid central Australia: a 10-year study." Wildlife Research 28, no. 5 (2001): 493. http://dx.doi.org/10.1071/wr00023.
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This study investigated the population dynamics of three species of dasyurid marsupials in sand ridge habitat of the Simpson Desert, western Queensland, over a 10-year period between March 1990 and December 1999. The lesser hairy-footed dunnart (Sminthopsis youngsoni), was captured most consistently over the period of study, followed by the wongai ningaui (Ningaui ridei), and the mulgara (Dasycercus cristicauda). Rates of recapture were low (4.5–22.2%), probably because individuals of each species are very mobile. All species bred in late winter or early spring when animals were aged at least 8–10 months, and independent juveniles first appeared usually in summer. S. youngsoni reared a second litter in late spring or early summer in 3 of the 10 years studied, when the availability of food was likely to have been high; neither N. ridei nor D. cristicauda were known to attempt a second litter within a season. To explore factors that might influence population dynamics, we compared capture rates of each species with measures of rainfall, temperature, vegetation cover, abundance of predators [feral cats (Felis catus), red foxes (Vulpes vulpes), and goannas (Varanus spp.)], dragons, other dasyurids and indices of food abundance. The abundance of S. youngsoni appeared to depend primarily on the cover of spinifex 7–9 months earlier, that of D. cristicauda was related most strongly to rainfall 7–9 months earlier, while that of N. ridei was related to minimum temperature lagged by 1–3 months. While the dynamics of other arid-zone mammals are driven demonstrably by interactions between rainfall, resource availability and predation, our findings suggest that dasyurids have limited flexibility in their life histories and are influenced more subtly and by factors such as facilitation that are just beginning to become apparent.
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Tsang, S. T. J., M. P. McHugh, D. Guerendiain, P. J. Gwynne, J. Boyd, A. H. R. W. Simpson, T. S. Walsh, I. F. Laurenson, and K. E. Templeton. "Underestimation of Staphylococcus aureus (MRSA and MSSA) carriage associated with standard culturing techniques." Bone & Joint Research 7, no. 1 (January 2018): 79–84. http://dx.doi.org/10.1302/2046-3758.71.bjr-2017-0175.r1.
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Objectives Nasal carriers of Staphylococcus (S.) aureus (MRSA and MSSA) have an increased risk for healthcare-associated infections. There are currently limited national screening policies for the detection of S. aureus despite the World Health Organization’s recommendations. This study aimed to evaluate the diagnostic performance of molecular and culture techniques in S. aureus screening, determine the cause of any discrepancy between the diagnostic techniques, and model the potential effect of different diagnostic techniques on S. aureus detection in orthopaedic patients. Methods Paired nasal swabs for polymerase chain reaction (PCR) assay and culture of S. aureus were collected from a study population of 273 orthopaedic outpatients due to undergo joint arthroplasty surgery. Results The prevalence of MSSA nasal colonization was found to be between 22.4% to 35.6%. The current standard direct culturing methods for detecting S. aureus significantly underestimated the prevalence (p = 0.005), failing to identify its presence in approximately one-third of patients undergoing joint arthroplasty surgery. Conclusion Modelling these results to national surveillance data, it was estimated that approximately 5000 to 8000 S. aureus surgical site infections could be prevented, and approximately $140 million to $950 million (approximately £110 million to £760 million) saved in treatment costs annually in the United States and United Kingdom combined, by using alternative diagnostic methods to direct culture in preoperative S. aureus screening and eradication programmes. Cite this article: S. T. J. Tsang, M. P. McHugh, D. Guerendiain, P. J. Gwynne, J. Boyd, A. H. R. W. Simpson, T. S. Walsh, I. F. Laurenson, K. E. Templeton. Underestimation of Staphylococcus aureus (MRSA and MSSA) carriage associated with standard culturing techniques: One third of carriers missed. Bone Joint Res 2018;7:79–84. DOI: 10.1302/2046-3758.71.BJR-2017-0175.R1.
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Delavau, Carly J., Tricia Stadnyk, and Tegan Holmes. "Examining the impacts of precipitation isotope input (<i>δ</i><sup>18</sup>O<sub>ppt</sub>) on distributed, tracer-aided hydrological modelling." Hydrology and Earth System Sciences 21, no. 5 (May 30, 2017): 2595–614. http://dx.doi.org/10.5194/hess-21-2595-2017.
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Abstract. Tracer-aided hydrological models are becoming increasingly popular tools as they assist with process understanding and source separation, which facilitates model calibration and diagnosis of model uncertainty (Tetzlaff et al., 2015; Klaus and McDonnell, 2013). Data availability in high-latitude regions, however, proves to be a major challenge associated with this type of application (Tetzlaff et al., 2015). Models require a time series of isotopes in precipitation (δ18Oppt) to drive simulations, and throughout much of the world – particularly in sparsely populated high-latitude regions – these data are not widely available. Here we investigate the impact that choice of precipitation isotope product (δ18Oppt) has on simulations of streamflow, δ18O in streamflow (δ18OSF), resulting hydrograph separations, and model parameters. In a high-latitude, data-sparse, seasonal basin (Fort Simpson, NWT, Canada), we assess three precipitation isotope products of different spatial and temporal resolutions (i.e. semi-annual static, seasonal KPN43, and daily bias-corrected REMOiso), and apply them to force the isoWATFLOOD tracer-aided hydrologic model. Total simulated streamflow is not significantly impacted by choice of δ18Oppt product; however, simulated isotopes in streamflow (δ18OSF) and the internal apportionment of water (driven by model parameterization) are impacted. The highest-resolution product (REMOiso) was distinct from the two lower-resolution products (KPN43 and static), but could not be verified as correct due to a lack of daily δ18Oppt observations. The resolution of δ18Oppt impacts model parameterization and seasonal hydrograph separations, producing notable differences among simulations following large snowmelt and rainfall events when event compositions differ significantly from δ18OSF. Capturing and preserving the spatial variability in δ18Oppt using distributed tracer-aided models is important because this variability impacts model parameterization. We achieve an understanding of tracer-aided modelling and its application in high-latitude regions with limited δ18Oppt observations, and the value such models have in defining modelling uncertainty. In this study, application of a tracer-aided model is able to identify simulations with improved internal process representation, reinforcing the fact that tracer-aided modelling approaches assist with resolving hydrograph component contributions and work towards diagnosing equifinality.
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Li, Yuanyuan, Han Chen, Qianyun Song, Jiahui Liao, Ziqian Xu, Shide Huang, and Honghua Ruan. "Changes in Soil Arthropod Abundance and Community Structure across a Poplar Plantation Chronosequence in Reclaimed Coastal Saline Soil." Forests 9, no. 10 (October 15, 2018): 644. http://dx.doi.org/10.3390/f9100644.
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Poplar plantations have the capacity to improve the properties of soils in muddy coastal areas; however, our understanding of the impacts of plantation development on soil arthropods remains limited. For this study, we determined the community dynamics of soil dwelling arthropods across poplar plantations of different ages (5-, 10-, and 21-years) over the course of one year in Eastern Coastal China. The total abundance of soil arthropods differed with stand development. Further, there were some interactions that involved the sampling date. On average, total abundance was highest in the 10-year-old stands and lowest in the 5-year-old stands. Total abundance exhibited strong age-dependent trends in June and September, but not in March or December. The abundance of Prostigmata and Oribatida increased in the 5- to 21-year-old stands, with the highest levels being in the 10-year-old stands. The abundance of Collembola increased with stand development; however, the stand age had no significant impact on the abundance of epedapic, hemiedaphic, and euedaphic Collembola. Order richness (Hill number q = 0) curve confidence intervals overlapped among three stand ages. Shannon and Simpson diversity (Hill numbers q = 1 and q = 2) differed between 10- and 21-year-old stand age. They showed almost similar trends, and the highest and lowest values were recorded in the 21- and 10-year-old stand ages, respectively. Permutational multivariate analysis of variance demonstrated that composition also varied significantly with the sampling date and stand age, and the 10-year-old stands that were sampled in June stood well-separated from the others. Indicator analysis revealed that Scolopendromorpha and Prostigmata were indicators in June for the 10-year-old stands, while Collembola were indicators for the 21-year-old stands sampled in September. Our results highlight that both stand development and climate seasonality can significantly impact soil arthropod community dynamics in the reclaimed coastal saline soils of managed poplar plantations.
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Pilkington, M., W. F. Miles, G. M. Ross, and W. R. Roest. "Potential-field signatures of buried Precambrian basement in the Western Canada Sedimentary Basin." Canadian Journal of Earth Sciences 37, no. 11 (November 1, 2000): 1453–71. http://dx.doi.org/10.1139/e00-020.
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An internally consistent, levelled compilation of magnetic data is derived for Alberta and northeastern British Columbia. With Bouguer gravity data, this compilation is used to refine the definition of Precambrian basement domains within the Western Canada Sedimentary Basin. Magnetic data are draped at a constant distance above the mapped basement surface to reduce the effects of varying magnetic source depths. Automated interpretation methods that effectively map outlines of magnetic sources are used to characterize the internal structure of the domains and to aid in their delineation. The basement domain map thus derived differs from previous interpretations in the extension of domains further to the southwest, due mainly to the availability of new public-domain magnetic data and the more precise definition of domain boundaries, based on the magnetic source location maps. The Nahanni, Hottah, Chinchaga, Thorsby, Vulcan, and Kiskatinaw domains are weakly magnetic and characterized by magnetic sources that are paramagnetic, comprising low-susceptibility silicate minerals. All other domains are characterized by the presence of ferrimagnetic material, most likely magnetite, which has a sufficiently high susceptibility to produce measurable anomalies. The largest anomalies and magnetizations are found in the Fort Nelson, Fort Simpson, Buffalo Head, Talston, Ksituan, and Matzhiwin domains. Such large magnetizations are usually indicative of intermediate igneous rocks associated with magmatic arc environments. Moderate-amplitude anomalies and (or) magnetizations are characteristic of the Nova, Wabamun, Lacombe, Rimbey, Loverna, and Medicine Hat domains, suggesting the presence of ferrimagnetic basic and granitoid rocks. Within some of the moderately magnetic domains are areas of paramagnetic lithologies that produce no magnetic anomalies. The narrower regions of magnetic lows, such as the Thorsby, Kiskatinaw, and Vulcan domains, are interpreted as resulting from demagnetization effects accompanying collision. Since demagnetization zones are limited in areal extent, the wider, more extensive magnetic lows of the Chinchaga and Hottah domains likely result from a combination of boundary demagnetization and a lower bulk magnetization level of crustal lithologies present.