On the KO Characteristic Cycle of a Spinc Manifold

2004 ◽  
Vol 115 (1) ◽  
Author(s):  
Jody Lynn Fast ◽  
Serge Ochanine
Keyword(s):  
Characteristic Cycle

scholarly journals Wild ramification and the characteristic cycle of an ℓ-adic sheaf

2009 ◽  
Vol 8 (4) ◽  
pp. 769-829 ◽  
Author(s):  
Takeshi Saito
Keyword(s):  
Local Field ◽  
Cotangent Bundle ◽  
Euler Number ◽  
Residue Field ◽  
Geometric Method ◽  
Characteristic Class ◽  
Wild Ramification ◽  
Characteristic Cycle

AbstractWe propose a geometric method to measure the wild ramification of a smooth étale sheaf along the boundary. Using the method, we study the graded quotients of the logarithmic ramification groups of a local field of characteristic p > 0 with arbitrary residue field. We also define the characteristic cycle of an ℓ-adic sheaf, satisfying certain conditions, as a cycle on the logarithmic cotangent bundle and prove that the intersection with the 0-section computes the characteristic class, and hence the Euler number.

scholarly journals Generalized Lyubeznik numbers

2014 ◽  
Vol 215 ◽  
pp. 169-201 ◽  
Author(s):  
Luis Núñez-Betancourt ◽  
Emily E. Witt
Keyword(s):  
Local Ring ◽  
Characteristic Zero ◽  
Monomial Ideals ◽  
Finitely Generated ◽  
Classical Version ◽  
Determinantal Ideals ◽  
Characteristic Cycle ◽  
Lyubeznik Numbers

AbstractGiven a local ring containing a field, we define and investigate a family of invariants that includes the Lyubeznik numbers but captures finer information. These generalized Lyubeznik numbers are defined in terms of D-modules and are proved well defined using a generalization of the classical version of Kashiwara’s equivalence for smooth varieties; we also give a definition for finitely generated K-algebras. These new invariants are indicators of F-singularities in characteristic p > 0 and have close connections with characteristic cycle multiplicities in characteristic zero. We characterize the generalized Lyubeznik numbers associated to monomial ideals and compute examples of those associated to determinantal ideals.

In vitro cultivation and developmental cycle in culture of a parasitic dinoflagellate (Hematodinium sp.) associated with mortality of the Norway lobster (Nephrops norvegicus) in British waters

Parasitology ◽  
1998 ◽  
Vol 116 (2) ◽  
pp. 115-130 ◽  
Author(s):  
P. L. APPLETON ◽  
K. VICKERMAN
Keyword(s):  
Calf Serum ◽  
Aquatic Organisms ◽  
Fresh Medium ◽  
Developmental Cycle ◽  
In Vitro Cultivation ◽  
Foetal Calf Serum ◽  
Nephrops Norvegicus ◽  
Norway Lobster ◽  
Characteristic Cycle

Dinoflagellates are common and often important parasites of aquatic organisms, but their developmental cycles are poorly known and have not been established in in vitro culture. The parasitic dinoflagellate (Hematodinium sp.) associated with mortality of the Norway lobster (Nephrops norvegicus) in British waters has been cultivated in vitro in 10% foetal calf serum in a balanced Nephrops saline. In culture the parasite undergoes a characteristic cycle of development. Circulating sporoblasts from the host's haemolymph in vitro generate 2 kinds of flagellated uninucleate dinospore, macrospores and microspores, either of which will, after 5 weeks in fresh medium, germinate to produce multinucleate unattached filamentous trophonts. These trophonts multiply by fragmentation and growth and may be serially subcultured in this form, at 2 week intervals, indefinitely. If not subcultured, the filamentous trophonts give rise to colonies of radiating filaments (‘gorgonlocks’) which subsequently attach to the substratum to form flattened web-like ‘arachnoid’ multi-nucleate trophonts. Arachnoid trophonts become arachnoid sporonts when they synthesize trichocysts and flagellar hairs and may give rise to secondary arachnoid sporonts or to dinospores which initiate a new cycle.

The Imaginal Ecdysis of Blowflies. Observations On the Hydrostatic Mechanisms Involved in Digging and Expansion

1962 ◽  
Vol 39 (3) ◽  
pp. 431-448 ◽  
Author(s):  
C. B. COTTRELL
Keyword(s):  
Hydrostatic Pressure ◽  
Atmospheric Pressure ◽  
Abdominal Muscles ◽  
Expansion Process ◽  
Gradual Rise ◽  
Characteristic Cycle ◽  
Pressure Pulses ◽  
Pressure Changes ◽  
Internal Pressures

1. The digging movements and the expansion process of newly emerged blowflies involve the production of positive internal pressures. 2. During digging newly emerged blowflies produce a characteristic cycle of internal hydrostatic pressure changes which in Sarcophaga reach, at their maximum, 6-12 cm. of mercury. 3. During expansion, two different pressure phenomena are detectable. First, there is a gradual rise and fall in the basic haemolymph pressure which reaches a maximum (of 6 cm. of mercury in Calhphora and 9-5 cm. in Sarcophaga) a few minutes after full wing extension and then falls to atmospheric pressure in the next 20 min. Secondly, superimposed on the basic rise there is a series of brief rhythmic pressure pulses which gradually decline and then cease about the time of full wing extension. 4. Evidence obtained by blocking the proboscis or denervating the abdominal muscles of newly emerged flies indicates that the gradual rise in haemolymph pressure s attributable to air-swallowing and the pressure pulses to the performance of ‘muscular efforts’ (i.e. simultaneous contractions of both the ptilinal and abdominal muscles). 5. The wing expansion of flies which have had their abdominal muscles denervated is abnormal, suggesting that at least some of these muscles play a part in bringing about normal expansion. 6. After full wing extension has occurred (or after an operated fly has reached a point in the air-pumping cycle at which expansion would have occurred) ‘muscular efforts’ cease and digging movements can no longer be stimulated. 7. This cessation is not due to the hardening of the cuticle and it is suggested that it is due to loss of the ability to excite the muscles concerned. 8. Within a few days of emergence many (perhaps all) of the muscles concerned in the production of digging movements ‘muscular efforts’ degenerate. 9. Immediately after expansion flies eliminate large quantities of fluid via the anus. This appears to be correlated with the change from a combined hydrostatic and external skeleton to a hard exoskeleton.

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