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Does defensive posture in.r.ase mimetic fidelity of caterpillars with eyespots to their putative snake models？

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Current Zoology 2014年第1期60卷 76-89页

作者： thomas John HOSSIE thomas n. SHErrATT Ottawa-Carleton Institute of Biology Carleton University 1125 Colonel By Drive Ottawa ON K1S 5B6 Canada Department of Biology Carleton University 1125 Colonel By Drive Ottawa ON K1S 5B6 Canada

Organisms often evolve behaviours that in.r.ase or reinforce the protection from predators afforded by their morpho- logical defences. For example, mimetic animals may adopt postures or locomotory behaviours that emulate a characteristic fea- ture of their model to in.r.ase predator deception. Caterpillars with eyespots are thought to mimic snakes, and when threatened many of these caterpillars adopt a posture that appears to enhance this resemblance. Herein we evaluate the quantitative strength of evidence of behavioural mimicry in the caterpillars of 14 species by comparing how closely a series of putative snake-mimicking caterpillars resemble snakes while at rest and when threatened. Specifically, we quantified the head morphology and eye position of a range of snake species, as well as the shape of the apparent head （i.e. anterior body segments） and position of eyespots in caterpillars resting or in their defensive posture. This allowed us to objectively examine evidence for an in.r.ased resemblance to either snakes gen.r.lly, or to Viperidae snakes specifically, upon adopting the defensive posture. Widening the anterior body segments during the defensive posture typically made caterpillars appear more viper-like as opposed to more snake-like in gen.r.l. Enhanced resemblance to vipers upon mounting the defensive posture was apparent only from the dorsal view. Laterally, caterpillars more closely resembled snakes in the resting posture and shifting to the defensive posture instead reduced mimetic fidelity, Overall we found evidence for behavioural mimicry in all 14 species examined. We highlight that objectively quantifying mimetic fidelity can help identify key features involved in deception .

关键词： Behaviour Geometr!c morphometrics Protective colouration Mimicry Morphology Vipers

Continuous flow synthesis of plasmonic gold patches and nearly-complete nanoshells on polystyrene core particles

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Particuology 2023年第4期75卷 137-150页

作者： thomas Meincke robin n.Klupp Taylor Institute of Particle Technology Friedrich-Alexander University Erlangen-NürnbergCauerstrasse 491058ErlangenGermany Collaborative research Center 1411-Design of Particulate Products Friedrich-Alexander University Erlangen-n.r.berg Cauerstrasse 391058 Erlangen Germany

We describe the development of a T-mixer based continuous flow process for the coating of 86-500 nm diameter spherical polystyrene particles with thin gold patches by heterogeneous nucleation and *** establishing a suitable flow rate for good mixing and sufficiently uniform product morphology we systematically investigate the main.r.action *** reveals a considerable tunability of the patch morphology and,by virtue of the localized surface plasmon.r.sonance of gold,the optical properties of the product *** order to further widen the range of nanostructures accessible by our process,a second T-mixer was *** in.r.duced new gold precursor,leading to further growth of the patches that were formed after the first *** this approach,nearly-complete gold nanoshells could be produced in high yield on both small and large core particles,without the unwanted production of free-standing gold *** to the pronounced optical properties of nearly-complete gold nanoshells on small core particles,we could estimate from electrodynamic sim-ulations the equivalent shell thickness to be as low as 8.6 *** is significantly thinn.r.than can be routinely achieved using the standard seeded growth approach to synthesise gold *** results are therefore highly promising for the gram-scale synthesis of plasmon.r.sonant nanostructures with designed optical properties.

关键词： Continuous flow Core-shell particles Patchy particles nucleation Diffusion limited growth

Structural and luminescence enhancement properties of Eu^(3+)/Ag nanocrystallites doped SiO_2-TiO_2 matrices

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Journal of rare Earths 2013年第5期31卷 441-448页

作者： Arun Kumar K V revathy K P Prathibha Vasudevan Sunil thomas Biju P r Unnikrishnan n V School of Pure & Applied Physics Mahatma Gandhi University

We reported here the structural and optical characterisation of silver nanocrystallites/Eu3＋：SiO2-TiO2 matrices synthesised through sol-gel route. Structural characterisations were done by using en.r.y dispersive spectroscopy （EDX）, X-ray diffraction （XrD）, Fourier transform in.r.red spectroscopy （FTIr）, atomic force microscope （AFM） and transmission electron microscopy （TEM） measurements and optical characterisations were performed by absorption and emission spectroscopy. The TEM and XrD measurements confirmed the presence of nanocrystals. A broad absorption band was observed due to surface plasmon.r.sonance of silver nanocrystals. The effect of silver nanocrystals on the emission spectrum of Eu3＋ doped SiO2-TiO2 matrices was discussed. An attempt was made to explain this fluorescence enhancement by invoking phenomena such as en.r.y transfer, asymmetry ratio, surface plasmon, surface roughness, crystallinity and grain boundary. Our analysis, based on the experimental results, suggested that all the phenomena except crystallinity and grain boundary had favourable effects on fluorescence enhancement. We also estimated the relevant parameters associated with the phenomena that affected the fluorescence emission from the Eu3＋ ions in the matrix. It was seen that the theoretical estimate of fluorescence enhancement agreed well with the experimental estimate.

关键词： sol-gel luminescence SiO2-TiO2 silver nanoparticles rare earths

Compressional origin of the Aegean Orogeny,Greece

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Geoscience Frontiers 2022年第2期13卷 383-404页

作者： Michael P.Searle thomas n.Lamont Dept Earth Sciences Oxford UniversitySouth Parks RoadOxfordOX13ANUK School of Earth and Environmental Sciences University of St AndrewsSt AndrewsKY169ALUK

The Aegean Sea area is thought to be an actively extending back-arc region,n.r.h of the present day Hellenic volcanic arc and n.r.h-dipping subduction zone in the Eastern *** area shows extensive n.r.al faulting,ductile‘extensional’shear zones and extensional S-C fabrics throughout the islands that have previously been.r.lated to regional Aegean extension associated with slab rollback on the Hellenic Subduction *** this paper,we question this interpretation,and suggest the Cenozoic geodynamic evolution of the Aegean.r.gion is associated with a Late Cretaceous-Eocene nE-dipping subduction zone that was responsible for continentcontinent collision between Eurasia and Adria-Apulia/*** of eclogite and blueschist facies rocks in the Cyclades and kyanite-sillimanite grade gneisses in the naxos core complex have pressures that are far greater than could be accounted for purely by lithospheric extension and isostatic *** identify four stages of crustal shortening that affected the region prior to regional lithospheric extension,herein called the Aegean *** orogeny followed a classic Wilson cycle from early ophiolite obduction(ca.74 Ma)onto a previously passive continental margin,to attempted crustal subduction with HP eclogite and blueschist facies metamorphism(ca.54-45 Ma),through crustal thickening and regional kyanite-sillimanite grade Barroviantype metamorphism(ca.22-14 Ma),to orogenic collapse(ree periods of‘extensional’fabrics relate to:(1)Exhumation of blueschists and eclogite facies rocks showing tight-isoclinal folds and top-nE,base-SW fabrics,recording return flow along a subduction channel in a compressional tectonic setting(ca.50-35 Ma).(2)Extensional fabrics within the core complexes formed by exhumation of kyanite-and sillimanite gneisses showing thrust-related fabrics at the base and‘extensional’fabrics along the top(ca.18.5-14 Ma).(3)regional ductile-brittle‘extensional’fabrics and low-angle

关键词： Cyclades Ophiolite High-pressure metamorphism Core complex Compressional tectonics

Is the severity of gastroesophageal reflux dependent on hiatus hernia size?

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World Journal of Gastroenterology 2014年第6期20卷 1582-1584页

作者： thomas Franzén Lita Tibbling Faculty of Health and Sciences Link ping University Department of Surgery Vrinnevi Hospital Norrk ping

AIM: To determine if the severity of gastroesophageal reflux disease is dependent on the size of a hiatus hernia. METHODS: Seventy-five patients with either a small(n = 25), medium(n = 25) or large(n = 25) hiatus hernia(assessed by high resolution esophageal manometry) were investigated using 24-h esophageal monitoring and a self-assessed symptom questionnaire. The questionnaire comprised the following items, each graded from 0 to 3 according to severity: heartburn; pharyngeal burning sensation; acid regurgitation; and chest pain. rESULTS: The percentage total reflux time was significantly longer in the group with hernia of 5 cm or more compared with the group with a hernia of nd the group with a hernia of 3 to ryngeal burning sensation, heartburn and acid regurgitation were more common with large hernias than small hernias, but the frequency of chest pain was similar in all three hernia groups. COnCLUSIOn: Patients with a large hiatus hernia are more prone to have pathological gastroesophageal reflux and to have more acid symptoms than patients with a small hiatus hernia. However, it is unlikely that patients with an absence of acid symptoms will have pathological reflux regardless of hernia size.

关键词： Heartburn,Hiatus hernia Acid reflux

Factors influencing lower esophageal sphincter relaxation after deglutition

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World Journal of Gastroenterology 2011年第23期17卷 2844-2847页

作者： Lita Tibbling Per Gezelius thomas Franzén Department of Surgery University of LinkpingSE-581 85 LinkpingSweden Department of Surgery University of LinkpingSE-581 85 SynMed SE-117 43 StockholmSweden

AIM:To study the relationship between upper esophageal sphincter (UES) relaxation,peristaltic pressure and lower esophageal sphincter (LES) relaxation following deglutition in non-dysphagic ***:Ten non-dysphagic adult subjects had a high-resolution manometry probe passed transnasally and positioned to cover the UES,the esophageal body and the *** water swallows in each subject were analyzed for time lag between UES relaxation and LES relaxation,LES pressure at time of UES relaxation,duration of LES relaxation,the distance between the transition level (TL) and the LES,time in seconds that the peristaltic wave was before (negative value) or after the TL when the LES became relaxed,and the maximal peristaltic pressure in the body of the ***:relaxation of the LES occurred on average 3.5 s after the bolus had passed the UES and in most cases when the peristaltic wave front had reached the *** LES remained relaxed until the peristaltic wave faded away above the ***:LES relaxation seemed to be caused by the peristaltic wave pushing the bolus from behind against the LES gate.

关键词： Deglutition Lower esophageal sphincter Peristalsis relaxation Upper esophageal sphincter

natural forests in new Zealand–a large terrestrial carbon pool in a national state of equilibrium

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Forest Ecosystems 2021年第3期8卷 458-478页

作者： thomas Paul Mark O.Kimberley Peter n.Beets Scion Private Bag 3020Rotorua 3046New Zealand Environmental Statistics Ltd Whangapararoa 0930New Zealand retired(previously Scion) Rotorua 3010New Zealand

Background:natural forests cover approximately 29%of new Zealand’s landmass and represent a large terrestrial carbon *** 2002 new Zealand implemented its first representative plot-based natural forest inventory to assess carbon stocks and stock changes in these mostly undisturbed old-growth *** previous studies have provided estimates of biomass or carbon stocks,these were either not fully representative or lacked data from important pools such as dead wood(coarse woody debris).The current analysis provides the most complete estimates of carbon stocks and stock changes in natural forests in new ***:We present estimates of per hectare carbon stocks and stock changes in live and dead organic matter pools excluding soil carbon based on the first two measurement cycles of the new Zealand natural Forest Inventory carried out from 2002 to *** show that new Zealand’s natural forests are in balance and are neither a carbon source n.r.a carbon *** average total carbon stock was 227.0±14.4 tC·ha^(−1)(95%C.I.)and did not change significantly in the 7.7 years between measurements with the net annual change estimated to be 0.03±0.18 tC·ha^(−1)·yr^(−1).There was a wide variation in carbon stocks between forest *** forest had an averaged carbon stock of only 53.6±9.4 tC·ha^(−1) but had a significant sequestration.r.te of 0.63±0.25 tC·ha^(−1)·yr^(−1),while tall forest had an average carbon stock of 252.4±15.5 tC·ha^(−1),but its sequestration.r.te did not differ significantly from zero(−0.06±0.20 tC·ha^(−1)·yr^(−1)).The forest alliance with the largest average carbon stock in above and below ground live and dead organic matter pools was silver beech-red beech-kamahi forest carrying 360.5±34.6 tC·ha^(−1).Dead wood and litter comprised 27%of the total carbon ***:new Zealand’s natural Forest Inventory provides estimates of carbon stocks including estimates for difficult to measure pools such as dead wood and roots.I

关键词： Forest inventory natural forests Carbon stocks and change Terrestrial carbon pool

Improved DHOA-Fuzzy Based Load Scheduling in IoT Cloud Environment

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Computers, Materials & Continua 2022年第5期71卷 4101-4114页

作者： r.Joshua Samuel raj V.Ilango Prince thomas V.r.Uma Fahd n.Al-Wesabi radwa Marzouk Anwer Mustafa Hilal Department of Information Science&Engineering CMR Institute of TechnologyBengaluru560037India Department of Computer Application CMR Institute of TechnologyBangalore560037India School of Computing Woldia Institute of TechnologyWoldia UniversityEthiopia Department of Commerce School of CommerceFinance and AccountancyChrist UniversityBangalore560029India Department of Computer Science College of Science&Art at MahayilKing Khalid UniversitySaudi Arabia Faculty of Computer and IT Sana’a UniversityYemen Department of Information Systems College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversitySaudi Arabia Department of Computer and Self Development Preparatory Year DeanshipPrince Sattam bin Abdulaziz UniversityAlkharjSaudi Arabia

Internet of things (IoT) has been significantly raised owing to thedevelopment of broadband access network, machine learning (ML), big dataanalytics (BDA), cloud computing (CC), and so on. The development of IoTtechnologies has resulted in a massive quantity of data due to the existenceof several people linking through distinct physical components, indicatingthe status of the CC environment. In the IoT, load scheduling is realistictechnique in distinct data center to guarantee the network suitability by fallingthe computer hardware and software catastrophe and with right utilize ofresource. The ideal load balancer improves many factors of Quality of Service(QoS) like resource performance, scalability, response time, error tolerance,and efficiency. The scholar is assumed as load scheduling a vital problem inIoT environment. There are many techniques accessible to load scheduling inIoT environments. With this motivation, this paper presents an improved deerhunting optimization algorithm with Type II fuzzy logic (IDHOA-T2F) modelfor load scheduling in IoT environment. The goal of the IDHOA-T2F is todiminish the en.r.y utilization of integrated circuit of IoT node and enhancethe load scheduling in IoT environments. The IDHOA technique is derivedby integrating the concepts of nelder Mead (nM) with the DHOA. Theproposed model also synthesized the T2L based on fuzzy logic (FL) systemsto counterbalance the load distribution. The proposed model finds usefulto improve the efficiency of IoT system. For validating the enhanced loadscheduling performance of the IDHOA-T2F technique, a series of simulationstake place to highlight the improved performance. The experimental outcomesdemonstrate the capable outcome of the IDHOA-T2F technique over therecent techniques.

关键词： Load scheduling internet of things cloud computing metaheuristics fuzzy logic

Studies on composite solid propellant with tri-modal ammonium perchlorate containing an ultrafine fraction

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Defence Technology（防务技术） 2017年第4期13卷 239-245页

作者： K.V. Suresh Babu P. Kanaka raju C.r. thomas A. Syed Hamed K.n. ninan Solid Propellant Space Booster Plant Satish Dhawan Space Centre Sriharikota 524124 India rocket Propellant Plant Vikram Sarabhai Space Centre Thiruvananthapuram 695 022 India Department of Chemistry Indian Institute of Space Science and Technology Thiruvananthapuram 695 547 India

Composite solid propellant is prepared using tri-modal Ammonium perchlorate(AP)containing coarse,fine and ultrafine fractions of AP with average particle size(APS)340,40 and 5 mm respectively,in various compositions and their rheological,mechanical and burn.r.te characteristics are *** optimum combination of AP coarse to fine to ultrafine weight fraction was obtained by testing of series of propellant samples by varying the AP fractions at fixed solid *** concen.r.tion of aluminium was maintained constant throughout the experiments for ballistics *** propellant formulation prepared using AP with coarse to fine to ultrafine ratio of 67:24:9 has lowest viscosity for the propellant paste and highest tensile strength due to dense packing as supported by the literature.A minimum modulus value was also observed at 9 wt.%of ultrafine AP concen.r.tion indicates the maximum solids packing density at this ratio of AP *** burn.r.te is evaluated at different pressures to obtain pressure *** of ultrafine fraction of AP in propellant in.r.ased burn.r.te without adversely affecting the pressure *** solid loading propellants are prepared by in.r.ased AP concen.r.tion from 67 to 71 wt.%using AP with coarse to fine to ultrafine ratio of67:24:*** solid content up to 89 wt.%was achieved and hence in.r.ased solid motor *** unloading viscosity showed a trend with in.r.ased AP content and the propellant couldn't able to cast beyond 71 wt.%of *** properties were also studied and from the experiments noticed that%elongation decreased with in.r.ased AP content from 67 to 71 wt.%,whereas tensile strength and modulus *** rate in.r.ased with in.r.ased AP content and observed that pressure exponent also in.r.ased and it is high for the propellant containing with 71 wt.%of AP due to in.r.ased oxidiser to fuel *** composite solid propellant is prepared by using burn.r.te modifie

关键词： Ammonium perchlorate Composite propellant Burn rate Copper chromite Iron oxide