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Insect Science 2007年第6期14卷 511-518页

作者： TANIA NOBRe LINA NUNeS david e. BIGNeLL Laboratorio Nacional de engenharia Civil Nucleo de Estruturas de Madeira Lisboa Portugal Queen Mary University of London School of Biological and Chemical Sciences London UK Institute of Tropical Biology and Conservation Universiti Malaysia Sabah Kota Kinabalu Sabah Malaysia

The cryptic habits of subterranean termites restricts detailed analysis of their foraging patterns in situ, but the process is evidently dominated by tunnel constructions connecting the nest with woody resources discovered within the territory of each colony. In this study, tunnel formation and orientation were studied experimentally in the termite Reticulitermes grassei （Clement）, using 2-dimensional laboratory foraging arenas con- taining fine sand as the substratum. The building of exploratory tunnels over a 10-day period and the geometry of the resulting network are described. Fractal analysis showed that tunnel geometry had a fractal dimension, regardless of the total length tunnelled whether foragers encountered the food source or not. The bulk density of the sand in the arenas affected the distances tunnelled, with higher density reducing construction, but did not affect tunnel geometry. Tunnels were not discernibly orientated with respect to the positioning of the food source, even in a situation where termites had failed to find the food source at a distance of less than 50 mm, suggesting that volatiles from wood are not attractants.

关键词： foraging gallery fractal analysis Reticulitermes grassei search pattern,subterranean termites tunnel geometry

On a Measure of Non-compactness for Some Classical Operators

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Acta Mathematica Sinica,english Series 2006年第6期22卷 1847-1862页

作者： david e.eDMUNDS Alberto FIOReNZA Alexander MeSKHI School of Mathematics Cardiff University Dipartimentodi Costruzioni e Metodi Matematici in Architettura Scuola Normale Superiore

The measure of non-compactness is estimated from below for various operators, including the Hardy-Littlewood maximal operator, the fractional maximal operator and the Hilbert transform, all acting between weighted Lebesgue spaces. The identity operator acting between weighted Lebesgue spaces and also between the counterparts of these spaces with variable exponents is similarly analysed. These results enable the lack of compactness of such operators to be quantified.

关键词： measure of non-compactness maximal functions singular integrals embeddings weight

Negative consequences of positive feedbacks in US wild-fire management

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Forest ecosystems 2015年第2期2卷 57-66页

作者： david e Calkin Matthew P Thompson Mark A Finney Forestry Sciences Laboratory US Forest Service Rocky Mountain Research Station Fire Sciences Laboratory US Forest Service Rocky Mountain Research Station

Over the last two decades wildfire activity, damage, and management cost within the US have increased substantially. These increases have been associated with a number of factors including climate change and fuel accumulation due to a century of active fire suppression. The increased fire activity has occurred during a time of significant ex-urban development of the Wildland Urban Interface （WUI） along with increased demand on water resources originating on forested landscapes. These increased demands have put substantial pressure on federal agencies charged with wildfire management to continue and expand the century old policy of aggressive wildfire suppression. However, aggressive wildfire suppression is one of the major factors that drive the increased extent, intensity, and damage associated with the small number of large wildfires that are unable to be suppressed. In this paper we discuss the positive feedback loops that lead to demands for increasing suppression response while simultaneously increasing wildfire risk in the future. Despite a wealth of scientific research that demonstrates the limitations of the current management paradigm pressure to maintain the existing system are well entrenched and driven by the existing social systems that have evolved under our current management practice. Interestingly, US federal wildland fire policy provides considerable discretion for managers to pursue a range of management objectives however, societal expectations and existing management incentive structures result in policy implementation that is straining the resilience of fire adapted ecosystems and the communities that reside in and adjacent to them.

关键词： Wildfire suppression Wildfire paradox Wildland urban interface Resilience

Stereotactic radiosurgery for haemorrhagic cerebral cavernous malformation:a multi-institutional,retrospective study

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Stroke & Vascular Neurology 2024年第3期9卷 221-229,I0130,I0131页

作者： Chloe Dumot Georgios Mantziaris Sam Dayawansa Zhiyuan Xu Stylianos Pikis Selcuk Peker Yavuz Samanci Gokce D Ardor Ahmed M Nabeel Wael A Reda Sameh R Tawadros Khaled Abdelkarim Amr M N el-Shehaby Reem M emad eldin Ahmed H elazzazi Nuria Martínez Moreno Roberto MartínezÁlvarez Roman Liscak Jaromir May david Mathieu Jean-Nicolas Tourigny Manjul Tripathi Akshay Rajput Narendra Kumar Rupinder Kaur Piero Picozzi Andrea Franzini Herwin Speckter Wenceslao Hernandez Anderson Brito Ronald e Warnick Juan Alzate Douglas Kondziolka Greg N Bowden Samir Patel Jason Sheehan Department of Neurological Surgery Hospices Civils de LyonLyonFrance Department of Neurological Surgery University of VirginiaCharlottesvilleVirginiaUSA Department of Neurosurgery Koc University School of MedicineIstanbulTurkey Gamma-knife Center Nasser institute HospitalCairoEgypt Neurosurgery Department Benha UniversityBenhaEgypt Departments of Neurosurgery Ain Shams UniversityCairoEgypt Department of Clinical Oncology Ain Shams UniversityCairoEgypt Department of Radiation Oncology National Cancer InstituteCairo UniversityGizaEgypt Faculty of Medicine Extended Modular ProgramAin Shams UniversityCairoEgypt Department of Radiosurgery Rúber Internacional HospitalMadridSpain Department of Stereotactic and Radiation Neurosurgery Na Homolce HospitalPragueCzech Republic Neurosurgery Centre de recherche du CHUSUniversitéde SherbrookeSherbrookeQuebecCanada Neurosurgery PGIMERChandigarhChandigarhIndia Radiation Therapy PGIMERChandigarhChandigarhIndia Neurosurgery IRCCS Istituto Clinico HumanitasRozzanoMilanItaly Dominican Gamma Knife Center and Radiology Department CEDIMATSanto DomingoDominican Republic Gamma Knife Center Mayfield ClinicThe Jewish Hospital-Mercy HealthCincinnatiOhioUSA Neurosurgery NYU Langone HealthNew YorkNew YorkUSA Neurosurgery University of AlbertaEdmontonAlbertaCanada Division of Radiation Oncology Department of OncologyUniversity of AlbertaEdmontonAlbertaCanada

Background Cerebral cavernous malformations(CCMs)frequently manifest with *** radiosurgery(SRS)has been employed for CCM not suitable for *** effect on reducing haemorrhage risk is still *** aim of this study was to expand on the safety and efficacy of SRS for haemorrhagic *** This retrospective multicentric study included CCM with at least one haemorrhage treated with single-session *** annual haemorrhagic rate(AHR)was calculated before and after *** event analysis and Cox regression were used to evaluate factors associated with *** radiation effects(ARes)and occurrence of new neurological deficits were *** The study included 381 patients (median age:37.5 years(Q1–Q3:25.8–51.9))with 414 *** AHR from diagnosis to SRS excluding the first haemorrhage was 11.08 per 100 CCM-years and was reduced to 2.7 per 100 CCM-years after *** recurrent event analysis,SRS,HR 0.27(95%CI 0.17 to 0.44),ped with a decreased risk of haemorrhage,and the presence of developmental venous anomaly(DVA)with an increased risk,HR 1.60(95%CI 1.07 to 2.40),p=*** cumulative risk of first haemorrhage after SRS was 9.4%(95%CI 6%to 12.6%)at 5 years and 15.6%(95%CI%9 to 21.8%)at 10 *** doses>13 Gy,HR 2.27(95%CI 1.20 to 4.32),p=0.012 and the presence of DVA,HR 2.08(95%CI 1.00 to 4.31),p=0.049 were factors associated with higher probability of post-SRS ***-SRS haemorrhage was symptomatic in 22 out of 381(5.8%)patients,presenting with transient(15/381)or permanent(7/381)neurological *** occurred in 11.1%(46/414)CCM and was responsible for transient neurological deficit in 3.9%(15/381)of the patients and permanent deficit in 1.1%(4/381)of the *** doses>13 Gy and CCM volume>0.7 cc were associated with increased risk of ARe.

关键词： doses haemorrhagic diagnosis

Forge AHeAD with stricter criteria in future trials of embolic stroke of undetermined source

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Neural Regeneration Research 2022年第5期17卷 1009-1010页

作者： david Z.Rose Scott e.Kasner Department of Neurology Morsani College of MedicineUniversity of South FloridaTampaFLUSA Department of Neurology Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPAUSA

What lurks within the crypt?With more than 200 known causes of is chemic stroke(Saver,2016),what should be the minimum work up?Many centers offer high-resolution brain imaging and vessel studies,telemetry monitoring f... 详细信息

关键词： strict thoracic centers

Metabolic regulation of pyroptotic cell death expands the therapeutic landscape for treating inflammatory disease

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Signal Transduction and Targeted Therapy 2021年第2期6卷 202-203页

作者： david e.Place Thirumala-Devi Kanneganti Department of Immunology St.Jude Children’s Research HospitalMemphisTNUSA

A recent study in Science by Fiachra Humphries et al.1 reveals an important role for the metabolic intermediate fumarate in reducing gasdermin D-mediated *** work adds a new inhibitor to the growing toolkit with the potential for treating pyroptosis-driven inflammatory *** is an inflammatory programmed cell death pathway initiated by direct sensing of pathogen-derived ligands or indirect sensing of changes to the normal cell state through sensors that can activate the inflammasome.

关键词： inflammatory death al.

Impacts of bovine spongiform encephalopathy and avian influenza on U.S. meat demand

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Journal of Integrative Agriculture 2015年第6期14卷 1130-1141页

作者： Jianhong e Mu Bruce A McCarl Amy Hagerman david Bessler Department of Applied economics Oregon State University Department of Agricultural economics Texas A&M University Center for epidemiology and Animal Health Veterinary Services Animal and Plant Health Inspection Service United States Department of Agriculture

This paper examines the U.S. meat demand impacts of the announced outbreaks of bovine spongiform encephalopathy（BSe） and avian influenza（AI）. Findings indicate that beef and chicken demand was negatively affected by BSe and AI disease outbreaks. Specifically, in the short run, U.S. consumers shift demand due to both outbreaks but more so due to domestic disease outbreaks than for outbreaks occurring overseas-the impact of U.S. AI outbreaks is about 0.5% for beef and the impact of U.S. BSe cases is around –0.42% for beef and 0.4% for pork, respectively. Regarding the BSe shock on meat demand, there is a high rate of beef demand adjusted from disturbance to the long-run equilibrium and a lower adjustment rate for chicken demand because of the repeated outbreaks of AI worldwide. In the long run, information related to severe, persistently recurring overseas animal disease outbreaks changes U.S. consumers＇ meat consumption patterns. Although effects of animal diseases on U.S. meat demand were statistically significant, the magnitudes were small-the impact of WHO reported human death numbers for AI is 0.005% for beef, –0.002% for pork, and –0.006% for chicken and the impact of U.S. BSe cases is 1.1% for pork and –0.7% for chicken.

关键词： spongiform avian chicken bovine encephalopathy overseas disturbance adjustment pathogenic deaths

Ontogenetic shift in response to prey-derived chemical cues in prairie rattlesnakes Crotalus viridis viridis

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Current Zoology 2012年第4期58卷 549-555页

作者： Anthony J. SAVIOLA david CHISZAR Stephen e MACKeSSY School of Biological Sciences University of Northern Colorado 501 20th Street CB 92 Greeley CO 80639 USA Department of Psychology CB 345 University of Colorado Boulder Colorado 80309 USA

Snakes often have specialized diets that undergo a shift from one prey type to another depending on the life stage of the snake. Crotalus viridis viridis （prairie rattlesnake） takes different prey at different life stages, and neonates typically prey on ectotherms, while adults feed almost entirely on small endotherms. We hypothesized that elevated rates of tongue flicking to chemical stimuli should correlate with particular prey consumed, and that this response shifts from one prey type to another as in- dividuals age. To examine if an ontogenetic shift in response to chemical cues occurred, we recorded the rate of tongue flicking for 25 neonate, 20 subadult, and 20 adult （average SVL = 280.9, 552, 789.5 mm, respectively） wild-caught C. v. viridis to chemi- cal stimuli presented on a cotton-tipped applicator; water-soluble cues from two ectotherms （prairie lizard, Sceloporus undulatus, and house gecko, Hemidactylusfrenatus）, two endotherms （deer mouse, Peromyscus maniculatus and lab mouse, Mus musculus）, and water controls were used. Neonates tongue flicked significantly more to chemical cues of their common prey, S. undulatus, than to all other chemical cues; however, the response to this lizard＇s chemical cues decreased in adult rattlesnakes. Subadults tongue flicked with a higher rate of tongue flicking to both S. undulatus and P. maniculatus than to all other treatments, and adults tongue flicked significantly more to P. maniculatus than to all other chemical cues. In addition, all three sub-classes demonstrated a greater response for natural prey chemical cues over chemical stimuli of prey not encountered in the wild （M. musculus and H. frenatus）. This shift in chemosensory response correlated with the previously described ontogenetic shifts in C. v. viridis diet. Be-cause many vipers show a similar ontogenetic shift in diet and venom composition, we suggest that this shift in prey cue dis- crimination is likely a general phenomenon among viperid snakes.

关键词： Gape-limited predator Prey choice Trophic adaptation Vomeronasal chemoreception

Coordinated Control Architecture for Motion Management in ADAS Systems

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Ieee/CAA Journal of Automatica Sinica 2018年第2期5卷 432-444页

作者： Tzu-Chi Lin Siyuan Ji Charles e. Dickerson david Battersby the wolfson school of mechanical electrical and manufacturing engineeringloughborough universityLoughhoroughLE11 3TUUK jaguar land rover GaydonCV35 0RRUK ieee

Advanced driver assistance systems(ADAS) seek to provide drivers and passengers of automotive vehicles increased safety and comfort. Original equipment manufacturers are integrating and developing systems for distance keeping, lane keeping and changing and other functionalities. The modern automobile is a complex system of systems. How the functionalities of advanced driver assistance are implemented and coordinated across the systems of the vehicle is generally not made available to the wider research community by the developers and manufactures. This paper seeks to begin filling this gap by assembling open source physics models of the vehicle dynamics and ADAS command models. Additionally, in order to facilitate ADAS development and testing without having access to the details of ADAS, a coordinated control architecture for motion management is also proposed for distributing ADAS motion control commands over vehicle systems. The architecture is demonstrated in a case study where motion is coordinated between the steering and the braking systems, which are typically used only for a single functionality. The integrated vehicle and system dynamics using the coordinated control architecture are simulated for various driving tasks. It is seen that improved trajectory following can be achieved by the proposed coordinated control architecture. The models, simulations and control architecture are made available for open access.

关键词： Index Terms-Coordinated system feed-forward and feedbackcontrol integration control modeling and simulation tire mod-eling vehicle modeling vehicle dynamics control.

Machine learning and data-driven prediction of pore pressure from geophysical logs:A case study for the Mangahewa gas field,New Zealand

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Journal of Rock Mechanics and Geotechnical engineering 2022年第6期14卷 1799-1809页

作者： Ahmed e.Radwan david A.Wood Ahmed A.Radwan Faculty of Geography and Geology Institute of Geological SciencesJagiellonian UniversityKraków30-387Poland exploration Department Gulf of Suez Petroleum CompanyCairoEgypt DWA energy Limited LincolnUK Department of Geology Faculty of ScienceAl-Azhar UniversityAssiut BranchAssiut71524Egypt

Pore pressure is an essential parameter for establishing reservoir conditions,geological interpretation and drilling *** pressure prediction depends on information from various geophysical logs,seismic,and direct down-hole pressure ***,a level of uncertainty accompanies the prediction of pore pressure because insufficient information is usually recorded in many *** machine learning(ML)algorithms can decrease the level of uncertainty of pore pressure prediction uncertainty in cases where available information is *** this research,several ML techniques are applied to predict pore pressure through the over-pressured eocene reservoir section penetrated by four wells in the Mangahewa gas field,New *** predictions substantially outperform,in terms of prediction performance,those generated using a multiple linear regression(MLR)*** geophysical logs used as input variables are sonic,temperature and density logs,and some direct pore pressure measurements were available at the reservoir level to calibrate the predictions.A total of 25,935 data records involving six well-log input variables were evaluated across the four *** ML methods achieved credible levels of pore pressure prediction *** most accurate models for predicting pore pressure in individual wells on a supervised basis are decision tree(DT),adaboost(ADA),random forest(RF)and transparent open box(TOB).The DT achieved root mean square error(RMSe)ranging from 0.25 psi to 14.71 psi for the four *** trained models were less accurate when deployed on a semi-supervised basis to predict pore pressure in the other *** two wells(Mangahewa-03 and Mangahewa-06),semi-supervised prediction achieved acceptable prediction performance of RMSe of 130—140 psi;while for the other wells,semi-supervised prediction performance was reduced to RMSe>300 *** results suggest that these models can be used to predict pore pressure in nearby locat

关键词： Machine learning(ML) Pore pressure Overburden Well-log derived predictions Overpressure