1,771 research outputs found
Recreational Fishing-Related Injuries to Australian Pelicans (Pelecanus Conspicillatus ) and Other Seabirds in a South Australian Estuarine and River Area
113 seabirds treated over 5.5 years had 132 fishing-related injuries that included entanglement with line only (N=35/132; 26.5%), entanglement
with line and an associated hook (N=47/132; 35.6%), embedded hooks only (N=34/132; 25.7%) and foreign body ingestion (N=16/132; 12.1%). The percentage of fishing-related injuries ranged from 0.9% for banded stilts (Cladorhynchus leucocephalus), pacific gulls (Larus pacificus) and masked lapwing plovers (Vanellus miles), to 59.3% for Australian pelicans (Pelecanus conspicillatus). Entanglement and/or embedded hooks were present more often than injuries from ingestion; i.e. 97% (70/72) of pelicans had entanglement and/or embedded hook injuries; of these 35/72 [48.6%] were entangled with line and hooks, 24/72 [33.3%] had embedded hooks alone and 11/72 [15.3%] were entangled with lines only, with only 3% (2/72) having injuries from ingestion. A count of sea and river birds in close proximity to fishers revealed that the majority were pelicans (33.9%), compared to pied cormorants (28.6%), silver gulls (21.4%) and black swans (16.1%). Regular removal of discarded fishing material along local shores resulted in no reduction in the numbers of entangled or hooked seabirds. It appears likely, therefore, that such injuries may result from seabird proximity to active recreational fishing, rather than from entanglement in discarded material
Global pseudodifferential operators of infinite order in classes of ultradifferentiable functions
[EN] We develop a theory of pseudodifferential operators of infinite order for the global classes S. of ultradifferentiable functions in the sense of Bjorck, following the previous ideas given by Prangoski for ultradifferentiable classes in the sense of Komatsu. We study the composition and the transpose of such operators with symbolic calculus and provide several examples.The first author was partially supported by the project GV Prometeo 2017/102, and the second author by the project MTM2016-76647-P. This article is part of the PhD. Thesis of V. Asensio. The authors are very grateful to the two referees for the careful reading and their suggestions and comments, which improved the paper.Asensio, V.; Jornet Casanova, D. (2019). Global pseudodifferential operators of infinite order in classes of ultradifferentiable functions. Revista de la Real Academia de Ciencias Exactas FĂsicas y Naturales Serie A MatemĂĄticas. 113(4):3477-3512. https://doi.org/10.1007/s13398-019-00710-8S347735121134Albanese, A.A., Jornet, D., Oliaro, A.: Wave front sets for ultradistribution solutions of linear partial differential operators with coefficients in non-quasianalytic classes. Math. Nachr. 285(4), 411â425 (2012)Björck, G.: Linear partial differential operators and generalized distributions. Ark. Mat. 6, 351â407 (1966)Boiti, C., Jornet, D., Oliaro, A.: Regularity of partial differential operators in ultradifferentiable spaces and Wigner type transforms. J. Math. Anal. Appl. 446(1), 920â944 (2017)Bonet, J., Meise, R., Melikhov, S.N.: A comparison of two different ways to define classes of ultradifferentiable functions. Bull. Belg. Math. Soc. Simon Stevin 14(3), 425â444 (2007)Braun, R.W., Meise, R., Taylor, B.A.: Ultradifferentiable functions and Fourier analysis. Results Math. 17(3â4), 206â237 (1990)Braun, R.W.: An extension of Komatsuâs second structure theorem for ultradistributions. J. Fac. Sci. Univ. Tokyo Sect. IA Math. 40(2), 411â417 (1993)Cappiello, M.: Fourier integral operators of infinite order and applications to SG-hyperbolic equations. Tsukuba J. Math. 28(2), 311â361 (2004)Cappiello, M., PilipoviÄ, S., Prangoski, B.: Parametrices and hypoellipticity for pseudodifferential operators on spaces of tempered ultradistributions. J. Pseudo-Differ. Oper. Appl. 5(4), 491â506 (2014)FernĂĄndez, C., Galbis, A., Jornet, D.: -hypoelliptic differential operators of constant strength. J. Math. Anal. Appl. 297(2), 561â576 (2004). Special issue dedicated to John HorvĂĄthFernĂĄndez, C., Galbis, A., Jornet, D.: Pseudodifferential operators on non-quasianalytic classes of Beurling type. Studia Math. 167(2), 99â131 (2005)FernĂĄndez, C., Galbis, A., Jornet, D.: Pseudodifferential operators of Beurling type and the wave front set. J. Math. Anal. Appl. 340(2), 1153â1170 (2008)Hashimoto, S., Morimoto, Y., Matsuzawa, T.: OpĂ©rateurs pseudodiffĂ©rentiels et classes de Gevrey. Commun. Partial Differ. Equ. 8(12), 1277â1289 (1983)Hörmander, L.: Pseudo-differential operators. Commun. Pure Appl. Math. 18, 501â517 (1965)Kohn, J.J., Nirenberg, L.: An algebra of pseudo-differential operators. Commun. Pure Appl. Math. 18, 269â305 (1965)Komatsu, H.: Ultradistributions. I. Structure theorems and a characterization. J. Fac. Sci. Univ. Tokyo Sect. IA Math. 20, 25â105 (1973)Langenbruch, M.: Continuation of Gevrey regularity for solutions of partial differential operators. In Functional analysis (Trier, 1994), pages 249â280. de Gruyter, Berlin (1996)Nicola, F.: Rodino, Luigi: Global pseudo-differential calculus on Euclidean spaces, volume 4 of Pseudo-Differential Operators. Theory and Applications. BirkhĂ€user Verlag, Basel (2010)Prangoski, B.: Pseudodifferential operators of infinite order in spaces of tempered ultradistributions. J. Pseudo-Differ. Oper. Appl. 4(4), 495â549 (2013)Rodino, L.: Linear partial differential operators in Gevrey spaces. World Scientific Publishing Co., Inc., River Edge (1993)Shubin, M.A.: Pseudodifferential operators and spectral theory. Springer-Verlag, Berlin, second edition. Translated from the 1978 Russian original by Stig I. Andersson (2001)Zanghirati, L.: Pseudodifferential operators of infinite order and Gevrey classes. Ann. Univ. Ferrara Sez. VII (N.S.) 31, 197â219, 1985 (1986
Molecular hydrogen beyond the optical edge of an isolated spiral galaxy
We know little about the outermost portions of galaxies because there is
little light coming from them. We do know that in many cases atomic hydrogen
(HI) extends well beyond the optical radius \cite{Casertano91}. In the centers
of galaxies, however, molecular hydrogen (H2) usually dominates by a large
factor, raising the question of whether H2 is abundant also in the outer
regions but hitherto unseen.Here we report the detection of emission from
carbon monoxide (CO), the most abundant tracer of H2, beyond the optical radius
of the nearby galaxy NGC 4414. The molecular clouds probably formed in the
regions of relatively high HI column density and in the absence of spiral
density waves. The relative strength of the lines from the two lowest
rotational levels indicates that both the temperature and density of the H2 are
quite low compared to conditions closer to the center. The inferred surface
density of the molecular material continues the monotonic decrease from the
inner regions. We conclude that while molecular clouds can form in the outer
region of this galaxy, there is little mass associated with them.Comment: 3 Nature page
Cercosporoid leaf pathogens from whorled milkweed and spineless safflower in California
Two cercosporoid species are respectively described from Mexican whorled milkweed (Asclepias fascicularis), and spineless safflower (Carthamus tinctorius) from California. Passalora californica represents a new pathogen on Asclepias fascicularis, while Ramularia cynarae is confirmed on Carthamus tinctorius and Cynara cardunculus (Asteraceae), and an epitype designated. Pathogenicity is also established for both pathogens based on Kochâs postulate
Asymptotic Regge Trajectories of Non-strange Mesons
We analyze the asymptotic behavior of Regge trajectories of non-strange
mesons. In contrast to an existing belief, it is demonstrated that for the
asymptotically linear Regge trajectories the width of heavy hadrons cannot
linearly depend on their mass. Using the data on masses and widths of rho_J,
omega_J, a_J and f_J mesons for the spin values J \leq 6, we extract the
parameters of the asymptotically linear Regge trajectory predicted by the
finite width model of quark gluon bags. As it is shown the obtained parameters
for the data set B correspond to the cross-over temperature lying in the
interval 170.9-175.3 MeV which is consistent with the kinetic freeze-out
temperature of early hadronizing particles found in relativistic heavy ion
collisions at and above the highest SPS energy.Comment: 14 pages, 3 figure
Prevalence and factors associated with poor performance in the 5âchair stand test: findings from the Cognitive Function and Ageing Study II and proposed Newcastle protocol for use in the assessment of sarcopenia
Background Poor performance in the 5âchair stand test (5âCST) indicates reduced lower limb muscle strength. The 5âCST has been recommended for use in the initial assessment of sarcopenia, the accelerated loss of muscle strength and mass. In order to facilitate the use of the 5âCST in sarcopenia assessment, our aims were to (i) describe the prevalence and factors associated with poor performance in the 5âCST, (ii) examine the relationship between the 5âCST and gait speed, and (iii) propose a protocol for using the 5âCST. Methods The populationâbased study Cognitive Function and Ageing Study II recruited people aged 65 years and over from defined geographical localities in Cambridgeshire, Newcastle, and Nottingham. The study collected data for assessment of functional ability during home visits, including the 5âCST and gait speed. We used multinomial logistic regression to assess the associations between factors including the SARCâF questionnaire and the category of 5âCST performance: fast (15 s), or unable, with slow/unable classed as poor performance. We reviewed previous studies on the protocol used to carry out the 5âCST. Results A total of 7190 participants aged 65+ from the three diverse localities of Cognitive Function and Ageing Study II were included (54.1% female). The proportion of those with poor performance in the 5âCST increased with age, from 34.3% at age 65â69 to 89.7% at age 90+. Factors independently associated with poor performance included positive responses to the SARCâF questionnaire, physical inactivity, depression, impaired cognition, and multimorbidity (all P < 0.005). Most people with poor performance also had slow gait speed (57.8%) or were unable to complete the gait speed test (18.4%). We found variation in the 5âCST protocol used, for example, timing until a participant stood up for the fifth time or until they sat down afterwards. Conclusions Poor performance in the 5âCST is increasingly common with age and is associated with a cluster of other factors that characterize risk for poor ageing such as physical inactivity, impaired cognition, and multimorbidity. We recommend a low threshold for performing the 5âCST in clinical settings and provide a protocol for its use
A characterization of the wave front set defined by the iterates of an operator with constant coefficients
[EN] We characterize the wave front set WF*P (u) with respect to the iterates of a linear partial differential operator with constant coefficients of a classical distribution u is an element of D '(Omega), Omega an open subset in R-n. We use recent Paley-Wiener theorems for generalized ultradifferentiable classes in the sense of Braun, Meise and Taylor. We also give several examples and applications to the regularity of operators with variable coefficients and constant strength. Finally, we construct a distribution with prescribed wave front set of this type.The authors were partially supported by FAR2011 (Universita di Ferrara), "Fondi per le necessita di base della ricerca" 2012 and 2013 (Universita di Ferrara) and the INDAM-GNAMPA Project 2014 "Equazioni Differenziali a Derivate Parziali di Evoluzione e Stocastiche" The research of the second author was partially supported by MINECO of Spain, Project MTM2013-43540-P.Boiti, C.; Jornet Casanova, D. (2017). A characterization of the wave front set defined by the iterates of an operator with constant coefficients. Revista de la Real Academia de Ciencias Exactas FĂsicas y Naturales Serie A MatemĂĄticas. 111(3):891-919. https://doi.org/10.1007/s13398-016-0329-8S8919191113Albanese, A.A., Jornet, D., Oliaro, A.: Quasianalytic wave front sets for solutions of linear partial differential operators. Integr. Equ. Oper. Theory 66, 153â181 (2010)Boiti, C., Jornet, D.: The problem of iterates in some classes of ultradifferentiable functions. In: âOperator Theory: Advances and Applicationsâ. Birkhauser, Basel. 245, 21â32 (2015)Boiti, C., Jornet, D., Juan-Huguet, J.,: Wave front set with respect to the iterates of an operator with constant coefficients. Abstr. Appl. Anal., 1â17 (2014). doi: 10.1155/2014/438716 (Article ID 438716)Bolley, P., Camus, J., Mattera, C.: AnalyticitĂ© microlocale et itĂ©rĂ©s dâoperateurs hypoelliptiques. In: SĂ©minaire GoulaouicâSchwartz, 1978â79, Exp N.13. Ăcole Polytech., PalaiseauBonet, J., FernĂĄndez, C., Meise, R.: Characterization of the Ï -hypoelliptic convolution operators on ultradistributions. Ann. Acad. Sci. Fenn. Math. 25, 261â284 (2000)Bonet, J., Meise, R., Melikhov, S.N.: A comparison of two different ways to define classes of ultradifferentiable functions. Bull. Belg. Math. Soc. Simon Stevin 14, 425â444 (2007)Braun, R.W., Meise, R., Taylor, B.A.: Ultradifferentiable functions and Fourier analysis. Result. Math. 17, 206â237 (1990)FernĂĄndez, C., Galbis, A., Jornet, D.: Ï -hypoelliptic differential operators of constant strength. J. Math. Anal. Appl. 297, 561â576 (2004)FernĂĄndez, C., Galbis, A., Jornet, D.: Pseudodifferential operators of Beurling type and the wave front set. J. Math. Anal. Appl. 340, 1153â1170 (2008)Hörmander, L.: On interior regularity of the solutions of partial differential equations. Comm. Pure Appl. Math. XI, 197â218 (1958)Hörmander, L.: Uniqueness theorems and wave front sets for solutions of linear partial differential equations with analytic coefficients. Comm. Pure Appl. Math. 24, 671â704 (1971)Hörmander, L.: The Analysis of Linear Partial Differential Operators I. Springer, Berlin (1990)Hörmander, L.: The Analysis of Linear Partial Differential Operators II. Springer, Berlin (1983)Juan-Huguet, J.: Iterates and hypoellipticity of partial differential operators on non-quasianalytic classes. Integr. Equ. Oper. Theory 68, 263â286 (2010)Juan-Huguet, J.: A PaleyâWiener type theorem for generalized non-quasianalytic classes. Studia Math. 208(1), 31â46 (2012)Komatsu, H.: A characterization of real analytic functions. Proc. Jpn. Acad. 36, 90â93 (1960)Kotake, T., Narasimhan, M.S.: Regularity theorems for fractional powers of a linear elliptic operator. Bull. Soc. Math. France 90, 449â471 (1962)Langenbruch, M.: P-Funktionale und Randwerte zu hypoelliptischen Differentialoperatoren. Math. Ann. 239(1), 55â74 (1979)Langenbruch, M.: Fortsetzung von Randwerten zu hypoelliptischen Differentialoperatoren und partielle Differentialgleichungen. J. Reine Angew. Math. 311/312, 57â79 (1979)Langenbruch, M.: On the functional dimension of solution spaces of hypoelliptic partial differential operators. Math. Ann. 272, 217â229 (1985)Langenbruch, M.: Bases in solution sheaves of systems of partial differential equations. J. Reine Angew. Math. 373, 1â36 (1987)MĂ©tivier, G.: PropriĂ©tĂ© des itĂ©rĂ©s et ellipticitĂ©. Comm. Partial Differ. Equ. 3(9), 827â876 (1978)Newberger, E., Zielezny, Z.: The growth of hypoelliptic polynomials and Gevrey classes. Proc. Amer. Math. Soc. 39(3), 547â552 (1973)Rodino, L.: On the problem of the hypoellipticity of the linear partial differential equations. In: Buttazzo, G. (ed.) Developments in Partial Differential Equations and Applications to Mathematical Physics. Plenum Press, New York (1992)Rodino, L.: Linear partial differential operators in Gevrey spaces. World Scientific, Singapore (1993)Zanghirati, L.: Iterates of a class of hypoelliptic operators and generalized Gevrey classes. Boll. U.M.I. Suppl. 1, 177â195 (1980
A simple proof of Kotake-Narasimhan theorem in some classes of ultradifferentiable functions
[EN] We give a simple proof of a general theorem of Kotake-Narasimhan for elliptic operators in the setting of ultradifferentiable functions in the sense of Braun, Meise and Taylor. We follow the ideas of Komatsu. Based on an example of Metivier, we also show that the ellipticity is a necessary condition for the theorem to be true.C. Boiti and D. Jornet were partially supported by the INdAM-GNAMPA Projects 2014 and 2015.
D. Jornet was partially supported by MINECO, Project MTM2013-43540-PBoiti, C.; Jornet Casanova, D. (2017). A simple proof of Kotake-Narasimhan theorem in some classes of ultradifferentiable functions. Journal of Pseudo-Differential Operators and Applications. 8(2):297-317. https://doi.org/10.1007/s11868-016-0163-yS29731782Boiti, C., Jornet, D.: The problem of iterates in some classes of ultradifferentiable functions. Oper. Theory Adv. Appl. Birkhauser Basel 245, 21â33 (2015)Boiti, C., Jornet, D.: A characterization of the wave front set defined by the iterates of an operator with constant coefficients. arXiv:1412.4954Boiti, C., Jornet, D., Juan-Huguet, J.: Wave front set with respect to the iterates of an operator with constant coefficients. Abstr. Appl. Anal. 2014, 1â17 Article ID 438716 (2014). doi: 10.1155/2014/438716Bolley, P., Camus, J., Mattera, C.: AnalyticitĂ© microlocale et itĂ©rĂ©s dâoperateurs hypoelliptiques. SĂ©minaire Goulaouic-Schwartz, 1978â1979, Exp No. 13, Ăcole Polytech, PalaiseauBonet, J., Meise, R., Melikhov, S.N.: A comparison of two different ways of define classes of ultradifferentiable functions. Bull. Belg. Math. Soc. Simon Stevin 14, 425â444 (2007)Braun, R.W., Meise, R., Taylor, B.A.: Ultradifferentiable functions and Fourier analysis. Result. Math. 17, 206â237 (1990)FernĂĄndez, C., Galbis, A.: Superposition in classes of ultradifferentiable functions. Publ. Res. I Math. Sci. 42(2), 399â419 (2006)Jornet Casanova, D.: Operadores Pseudodiferenciales en Clases no CasianalĂticas de Tipo Beurling. Universitat PolitĂšcnica de ValĂšncia (2004). doi: 10.4995/Thesis/10251/54953Juan-Huguet, J.: Iterates and hypoellipticity of partial differential operators on non-quasianalytic classes. Integr. Equ. Oper. Theory 68, 263â286 (2010)Juan-Huguet, J.: A PaleyâWiener type theorem for generalized non-quasianalytic classes. Stud. Math. 208(1), 31â46 (2012)Komatsu, H.: A characterization of real analytic functions. Proc. Jpn Acad. 36, 90â93 (1960)Komatsu, H.: On interior regularities of the solutions of principally elliptic systems of linear partial differential equations. J. Fac. Sci. Univ. Tokyo Sect. 1, 9, 141â164 (1961)Komatsu, H.: A proof of KotakĂ© and Narasimhanâs theorem. Proc. Jpn Acad. 38(9), 615â618 (1962)Kotake, T., Narasimhan, M.S.: Regularity theorems for fractional powers of a linear elliptic operator. Bull. Soc. Math. Fr. 90, 449â471 (1962)Kumano-Go, H.: Pseudo-Differential Operators. The MIT Press, Cambridge, London (1982)Langenbruch, M.: P-Funktionale und Randwerte zu hypoelliptischen Differentialoperatoren. Math. Ann. 239(1), 55â74 (1979)Langenbruch, M.: Fortsetzung von Randwerten zu hypoelliptischen Differentialoperatoren und partielle Differentialgleichungen. J. Reine Angew. Math. 311/312, 57â79 (1979)Langenbruch, M.: On the functional dimension of solution spaces of hypoelliptic partial differential operators. Math. Ann. 272, 217â229 (1985)Langenbruch, M.: Bases in solution sheaves of systems of partial differential equations. J. Reine Angew. Math. 373, 1â36 (1987)Lions, J.L., Magenes, E.: ProblĂšmes aux limites non homogĂšnes et applications, vol. 3. Dunod, Paris (1970)MĂ©tivier, G.: PropriĂ©tĂ© des itĂ©rĂ©s et ellipticitĂ©. Commun. Part. Differ. Eq. 3(9), 827â876 (1978)Nelson, E.: Analytic vectors. Ann. Math. 70, 572â615 (1959)Newberger, E., Zielezny, Z.: The growth of hypoelliptic polynomials and Gevrey classes. Proc. Am. Math. Soc. 39(3), 547â552 (1973)Oldrich, J.: Sulla regolaritĂ delle soluzioni delle equazioni lineari ellittiche nelle classi di Beurling. (Italian) Boll. Un. Mat. Ital. (4) 2, 183â195 (1969)Petzsche, H.-J., Vogt, D.: Almost analytic extension of ultradifferentiable functions and the boundary values of holomorphic functions. Math. Ann. 267(1), 17â35 (1984
Fracking in the UK press: threat dynamics in an unfolding debate
Shale gas is a novel source of fossil fuel which is extracted by induced hydraulic fracturing, or âfrackingâ. This article examines the socio-political dimension of fracking as manifested in the UK press at three key temporal points in the debate on the practice. Three newspaper corpora were analysed qualitatively using Thematic Analysis and Social Representations Theory. Three overarching themes are discussed: âAprilâMay 2011: From Optimism to Scepticismâ; âNovember 2011: (De-)Constructing and Re-Constructing Risk and Dangerâ; âApril 2012: Consolidating Social Representations of Frackingâ. In this article, we examine the emergence of and inter-relations between competing social representations, discuss the dynamics of threat positioning and show how threat can be re-construed in order to serve particular socio-political ends in the debate on fracking
Îł-Aminobutyric acid (GABA) signalling in human pancreatic islets is altered in type 2 diabetes
AIMS/HYPOTHESIS: Îł-Aminobutyric acid (GABA) is a signalling molecule in the interstitial space in pancreatic islets. We examined the expression and function of the GABA signalling system components in human pancreatic islets from normoglycaemic and type 2 diabetic individuals. METHODS: Expression of GABA signalling system components was studied by microarray, quantitative PCR analysis, immunohistochemistry and patch-clamp experiments on cells in intact islets. Hormone release was measured from intact islets. RESULTS: The GABA signalling system was compromised in islets from type 2 diabetic individuals, where the expression of the genes encoding the α1, α2, ÎČ2 and ÎČ3 GABA(A) channel subunits was downregulated. GABA originating within the islets evoked tonic currents in the cells. The currents were enhanced by pentobarbital and inhibited by the GABA(A) receptor antagonist, SR95531. The effects of SR95531 on hormone release revealed that activation of GABA(A) channels (GABA(A) receptors) decreased both insulin and glucagon secretion. The GABA(B) receptor antagonist, CPG55845, increased insulin release in islets (16.7 mmol/l glucose) from normoglycaemic and type 2 diabetic individuals. CONCLUSIONS/INTERPRETATION: Interstitial GABA activates GABA(A) channels and GABA(B) receptors and effectively modulates hormone release in islets from type 2 diabetic and normoglycaemic individuals
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