309 research outputs found
The Impact of Delivery Risk on Optimal Production and Futures Hedging
Multiple delivery specifications exist on nearly all commodity futures contracts. Sellers are typically allowed to choose among several grades of the underlying commodity. On the delivery day, the futures price converges to the spot price of the cheapest-to-deliver grade rather than to that of the par-delivery grade of the commodity, thereby imposing an additional delivery risk on hedgers. This paper derives the optimal production and futures hedging strategy for a risk-averse competitive firm facing delivery risk. We show that the option value of the multiple delivery specification induces the firm to produce more with than without the delivery risk if the firm gauges this value higher than the market. We further show that if the delivery risk is additively related to the commodity price risk, the firm optimally under-hedges its risk exposure. On the other hand, if the delivery risk is multiplicatively related to the commodity price risk, the firm may optimally choose an under- or over-hedge which we illustrate using a numerical example.link_to_subscribed_fulltex
Petrogenesis of kyanite-quartz segregations in mica schists of the Western Tatra Mountains (Slovakia)
In the Tatra Mountains (Slovakia) metamorphic complex, kyanite-quartz segregations with biotite-rich
selvage occur in mylonitized mica schists. In this paper, the problem of fluid flow and aluminium mobility during
the uplift of the crystalline massif, and the position of the segregations in the history of Western Tatra
metamorphic complex, is adressed. The reaction Alm + Rt Ilm + Ky + Qtz is considered to be the result of
a pressure drop from above to below 9 kbar. Ti-in-biotite geothermometry shows the temperature range to be 579-
639ºC that is related to heating and decompression associated with granite intrusion. Major-element mass-balance
calculations show that Al remained stable in the selvage + segregation system whereas other elements (e.g. Cr,
HFSE) were mobilized. The kyanite-quartz segregations formed from local fluids generated during dehydration of
the metapelitic rocks during uplift. The main mechanism was likely diffusion-driven mass-transfer into extensionrelated
cracks
The FLC-like gene BvFL1 is not a major regulator of vernalization response in biennial beets
Many plant species in temperate climate regions require vernalization over winter to initiate flowering. Flowering Locus C (FLC) and FLC-like genes are key regulators of vernalization requirement and growth habit in winter-annual and perennial Brassicaceae. In the biennial crop species Beta vulgaris ssp. vulgaris in the evolutionarily distant Caryophyllales clade of core eudicots growth habit and bolting time are controlled by the vernalization and photoperiod response gene BTC1 and the downstream BvFT1-BvFT2 module. B. vulgaris also contains a vernalization-responsive FLC homolog (BvFL1). Here, to further elucidate the regulation of vernalization response and growth habit in beet, we functionally characterized BvFL1 by RNAi and over-expression in transgenic plants. BvFL1 RNAi neither eliminated the requirement for vernalization of biennial beets nor had a major effect on bolting time after vernalization. Over-expression of BvFL1 resulted in a moderate late-bolting phenotype, with bolting after vernalization being delayed by approximately 1 week. By contrast, RNAi-induced down-regulation of the BvFT1-BvFT2 module led to a strong delay in bolting after vernalization by several weeks. The data demonstrate for the first time that an FLC homolog does not play a major role in the control of vernalization response in a dicot species outside the Brassicaceae
Multi-qubit doilies: enumeration for all ranks and classification for ranks four and five
For , an -qubit doily is a doily living in the -qubit
symplectic polar space. These doilies are related to operator-based proofs of
quantum contextuality. Following and extending the strategy of Saniga et al.
(Mathematics 9 (2021) 2272) that focused exclusively on three-qubit doilies, we
first bring forth several formulas giving the number of both linear and
quadratic doilies for any . Then we present an effective algorithm for
the generation of all -qubit doilies. Using this algorithm for and
, we provide a classification of -qubit doilies in terms of types of
observables they feature and number of negative lines they are endowed with. We
also list several distinguished findings about -qubit doilies that are
absent in the three-qubit case, point out a couple of specific features
exhibited by linear doilies and outline some prospective extensions of our
approach.Comment: Minor revisions and corrections. Published in Journal of
Computational Science, Volume 64, 2022, 101853, ISSN 1877-7503,
https://doi.org/10.1016/j.jocs.2022.10185
New and improved bounds on the contextuality degree of multi-qubit configurations
We present algorithms and a C code to decide quantum contextuality and
evaluate the contextuality degree (a way to quantify contextuality) for a
variety of point-line geometries located in binary symplectic polar spaces of
small rank. With this code we were not only able to recover, in a more
efficient way, all the results of a recent paper by de Boutray et al (J. Phys.
A: Math. Theor. 55 475301, 2022), but also arrived at a bunch of new noteworthy
results. The paper first describes the algorithms and the C code. Then it
illustrates its power on a number of subspaces of symplectic polar spaces whose
rank ranges from two to seven. The most interesting new results include: (i)
non-contextuality of configurations whose contexts are subspaces of dimension
two and higher, (ii) non-existence of negative subspaces of dimension three and
higher, (iii) considerably improved bounds for the contextuality degree of both
elliptic and hyperbolic quadrics for ranks four, as well as for a particular
subgeometry of the three-qubit space whose contexts are the lines of this
space, (iv) proof for the non-contextuality of perpsets and, last but not
least, (v) contextual nature of a distinguished subgeometry of a multi-qubit
doily, called a two-spread, and computation of its contextuality degree.Comment: 21 pages, 5 figures, 2 tables, submitte
Age and origin of fluorapatite-rich dyke from Baranec Mt. (Tatra Mts., Western Carpathians) : a key to understanding of the post-orogenic processes and element mobility
On the southeastern slope of the Baranec Mount in the Western Tatra Mountains (Slovakia) an apatite-rich pegmatite-like segregation was found in the subvertical fault zone cutting metapelitic rocks. Two zones: felsic (F) and mafic (M) were found, differing in mineral assemblages and consequently in chemistry. Fluorapatite crystals yield a LA-ICP-MS U-Pb age of 328.6 ± 2.4 Ma. A temperature decrease from 634 °C to 454 °C at a pressure around 500 to 400 MPa with oxygen fugacity increasing during crystallization are the possible conditions for formation of the pegmatite-like segregation, while secondary alterations took place in the temperature range of 340-320 °C. The Sr-Nd isotope composition of both apatite and whole rock point toward a crustal origin of the dike in question, suggesting partial melting of (P, F, H2O)-rich metasedimentary rocks during prolonged decompression of the Tatra Massif. The original partial melt (felsic component) was mixed with an external (F, H2O)-rich fluid, carrying Fe and Mg fluxed from more mafic metapelites and crystallizing as biotite and epidote in the mafic component of the dyke
The Molecular Ridge Close to 30 Doradus in the Large Magellanic Cloud
With the ATNF Mopra telescope we are performing a survey in the 12CO(1-0)
line to map the molecular gas in the Large Magellanic Cloud (LMC). For some
regions we also obtained interferometric maps of the high density gas tracers
HCO+ and HCN with the Australia Telescope Compact Array (ATCA). Here we discuss
the properties of the elongated molecular complex that stretches about 2 kpc
southward from 30 Doradus. Our data suggests that the complex, which we refer
to as the ``molecular ridge,'' is not a coherent feature but consists of many
smaller clumps that share the same formation history. Likely molecular cloud
formation triggers are shocks and shearing forces that are present in the
surrounding south-eastern HI overdensity region, a region influenced by strong
ram pressure and tidal forces. The molecular ridge is at the western edge of
the the overdensity region where a bifurcated velocity structure transitions
into a single disk velocity component. We find that the 12CO(1-0) and HI
emission peaks in the molecular ridge are typically near each other but never
coincide. A likely explanation is the conversion of warmer, low-opacity HI to
colder, high-opacity HI from which H2 subsequently forms. On smaller scales, we
find that very dense molecular gas, as traced by interferometric HCO+ and HCN
maps, is associated with star formation along shocked filaments and with rims
of expanding shell-like structures, both created by feedback from massive
stars.Comment: accepted for publication in the Publications of the Astronomical
Society of Australi
T cell derived IL-10 is dispensable for tolerance induction in a murine model of allergic airway inflammation
Regulatory mechanisms initiated by allergen specific immunotherapy are mainly attributed to T cell-derived IL-10. However, it has not been shown that T cell-derived IL-10 is required for successful tolerance induction. Here, we analyze cellular sources and the functional relevance of cell type specific IL-10 during tolerance induction in a murine model of allergic airway inflammation. While tolerance induction was effective in IL-10 competent mice, neutralizing IL-10 prior to tolerogenic treatment completely abrogated the beneficial effects. Cellular sources of IL-10 during tolerance induction were identified by using transcriptional reporter mice as T cells, B cells and to a lesser extent DCs. Interestingly, tolerance induction was still effective in mice with T cell-, B cell-, B and T cell- or DC-specific IL-10 deficiency. In contrast, tolerance induction was not possible in mice lacking IL-10 in all hematopoetic cells, while it was effective in bone marrow chimera that lacked IL-10 only in non-hematopoetic cells. Taken together, allergen specific tolerance depends on IL-10 from hematopoetic sources. The beneficial effects of allergen specific immunotherapy cannot solely be attributed to IL-10 from T cells, B cells or even DCs, suggesting a high degree of cellular redundancy in IL-10 mediated tolerance
A rating scale for the assessment of objective and subjective formal thought and language disorder (TALD)
Formal thought disorder (FTD) is a core syndrome of schizophrenia. However, patients with other diagnoses, such as mania and depression amongst others, also present with FTD. We introduce a novel, comprehensive clinical rating scale, capturing the full variety of FTD phenomenology including subjective experiences. The 30-item Thought and Language Disorder (TALD) scale is based on a detailed review of the literature, encompassing all formal thought disorder symptoms reported from the early 20th century onwards. Objectively observable symptoms as well as subjective phenomena were included. Two hundred and ten participants (146 patients ICD-10 diagnoses: depression n. = 63, schizophrenia n. = 63, mania n. = 20; 64 healthy control subjects) were interviewed and symptoms rated with the TALD, TLC, HAMD, YMRS and SAPS/SANS. A principal component analyses was performed for the TALD to differentiate sub-syndromes. The principal component analysis revealed four FTD factors; objective and subjective as well as positive and negative factor dimensions. The correlation analyses with the TLC and the SAPS/SANS FTD sub-scores demonstrated the factor validity for the objective factors. The different diagnoses showed a distinct pattern of symptom severity in each of the factors, with mania patients exhibiting the highest value in the positive, objective dimension. The scale showed good psychometric results, which makes it a practicable, nosologically-open instrument for the detailed assessment of all FTD dimensions. The results strengthen the importance of subjective symptom assessment reported by the patient.DFG (project no. Ki 588/6-1)Scopu
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