501 research outputs found
Brown representability for space-valued functors
In this paper we prove two theorems which resemble the classical
cohomological and homological Brown representability theorems. The main
difference is that our results classify small contravariant functors from
spaces to spaces up to weak equivalence of functors.
In more detail, we show that every small contravariant functor from spaces to
spaces which takes coproducts to products up to homotopy and takes homotopy
pushouts to homotopy pullbacks is naturally weekly equivalent to a
representable functor.
The second representability theorem states: every contravariant continuous
functor from the category of finite simplicial sets to simplicial sets taking
homotopy pushouts to homotopy pullbacks is equivalent to the restriction of a
representable functor. This theorem may be considered as a contravariant analog
of Goodwillie's classification of linear functors.Comment: 19 pages, final version, accepted by the Israel Journal of
Mathematic
Exploring the reactivity of 2-trichloromethylbenzoxazoles for access to substituted benzoxazoles
The reactivity of 2-trichloromethylbenzoxazoles towards various nucleophiles, under metal free or iron-catalyzed conditions, for the synthesis of substituted benzoxazoles is described. These methods allow for selective substitution at either the 2- or 2’- position of the benzoxazoles using the same starting materials / reagents. This approach allows for the controlled synthesis of a variety of key derivatives from a single 2-trichloromethylbenzoxazole starting material
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Progress report on the spruce budworm silvicultural demonstration project on the Gallatin and Lolo National Forests
"It All Ended in an Unsporting Way": Serbian Football and the Disintegration of Yugoslavia, 1989-2006
Part of a wider examination into football during the collapse of Eastern European Communism between 1989 and 1991, this article studies the interplay between Serbian football and politics during the period of Yugoslavia's demise. Research utilizing interviews with individuals directly involved in the Serbian game, in conjunction with contemporary Yugoslav media sources, indicates that football played an important proactive role in the revival of Serbian nationalism. At the same time the Yugoslav conflict, twinned with a complex transition to a market economy, had disastrous consequences for football throughout the territories of the former Yugoslavia. In the years following the hostilities the Serbian game has suffered decline, major financial hardship and continuing terrace violence, resulting in widespread nostalgia for the pre-conflict era
Differential FSH Glycosylation Modulates FSHR Oligomerization and Subsequent cAMP Signaling.
Follicle-stimulating hormone (FSH) and its target G protein-coupled receptor (FSHR) are essential for reproduction. Recent studies have established that the hypo-glycosylated pituitary FSH glycoform (FSH21/18), is more bioactive in vitro and in vivo than the fully-glycosylated variant (FSH24). FSH21/18 predominates in women of reproductive prime and FSH24 in peri-post-menopausal women, suggesting distinct functional roles of these FSH glycoforms. The aim of this study was to determine if differential FSH glycosylation modulated FSHR oligomerization and resulting impact on cAMP signaling. Using a modified super-resolution imaging technique (PD-PALM) to assess FSHR complexes in HEK293 cells expressing FSHR, we observed time and concentration-dependent modulation of FSHR oligomerization by FSH glycoforms. High eFSH and FSH21/18 concentrations rapidly dissociated FSHR oligomers into monomers, whereas FSH24 displayed slower kinetics. The FSHR β-arrestin biased agonist, truncated eLHβ (Δ121-149) combined with asparagine56-deglycosylated eLHα (dg-eLHt), increased FSHR homomerization. In contrast, low FSH21/18 and FSH24 concentrations promoted FSHR association into oligomers. Dissociation of FSHR oligomers correlated with time points where higher cAMP production was observed. Taken together, these data suggest that FSH glycosylation may modulate the kinetics and amplitude of cAMP production, in part, by forming distinct FSHR complexes, highlighting potential avenues for novel therapeutic targeting of the FSHR to improve IVF outcomes
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Evaluation of larch casebearer parasites on the Flathead National Forest, Montana, 1985
An evaluation during the summer of 1985 showed that parasites were still exerting control on the larch casebearer on the Flathead NF. Parasitism ranged from 4 to 60 percent and averaged 25.2 percent in the 12 areas surveyed. Four species of parasites were involved. The most abundant was Agathis pumila (Ratzeburg), an exotic wasp that was established within the Flathead NF from 1967 to 1969
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Observations on the impact of western spruce budworm on the Valley Creek Drainage, Flathead Indian Reservation, Montana
The western spruce budworm, Choristoneura occidentalis (Free.), has caused a measurable impact on a portion of the Flathead Indian Reservation during a 5-year infestation period. This survey showed that most of the grand fir and alpine fir, and 13.8 percent of the Douglas fir has been top killed in the Valley Creek area west of Arlee, Montana.
The survey also disclosed that a total net growth loss of 19.6± 1.9 board feet per acre per year has occurred since 1967. Significant growth reduction at the 99 percent level occurred in Douglas-fir, grand fir, alpine fir, and western larch. Little mortality in trees 5 inches d.b.h. and greater has occurred to date. Of the trees under 5 inches d.b.h. 55.6 percent were not suitable for Christmas tree production because of insect damage
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Application of predictive model to forecast Douglas-fir tussock moth defoliation
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Evaluation of forest insect conditions on the National Bison Range, Moiese, Montana
An evaluation of forest insect conditions on the National Bison Range at Moiese, Montana, was made on August 28, 1972
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