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Start Over Coverage 9-17

1. A 15,000-year history of Early Upper Paleolithic hunters moving through the Pustý Žleb valley - Artefacts and chronology of Pod Hradem Cave, Moravian Karst, Czech Republic

Creator:
Nejman, Ladislav, Škrdla, Petr, Wright, Duncan, Bartík, Jaroslav, and Přichystal, Antonín
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Middle-Upper Paleolithic transition, chronostratigraphy, stone artefacts, and EUP cultures
Language:
Czech
Description:
Archaeological evidence shows that Paleolithic hunters occasionally used the difficult-to-access Pod Hradem Cave for short-term visits. The small collection of artefacts spanning a c. 15,000-year period were made from a range of different raw materials collected from known sources in the surrounding regions up to 120 km away. In this paper, we interpret the sum of the archaeological evidence associated with artefacts from Pod Hradem Cave against an updated chronology, and report a previously unpublished stone artefact. Combined, this information suggests variable cave use throughout the site history. During the Early-Upper Paleolithic this likely involved visits by small, mobile bands using Pod Hradem Cave as a short stop over while passing through the Pustý Žleb valley.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2. Elevated CO2 and temperature differentially affect photosynthesis and resource allocation in flag and penultimate leaves of wheat

Creator:
Pérez, P., Zita, G., Morcuende, R., and Martínez-Carrasco, R.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
acclimation, ribulose-1,5-bisphosphate carboxylase, oxygenase, temperature, and Triticum aestivum
Language:
Multiple languages
Description:
Differences in acclimation to elevated growth CO2 (700 µmol mol-1, EC) and elevated temperature (ambient +4 °C, ET) in successive leaves of wheat were investigated in field chambers. At a common measurement CO2, EC increased photosynthesis and the quantum yield of electron transport (Φ) early on in the growth of penultimate leaves, and later decreased them. In contrast, EC did not change photosynthesis, and increased Φ at later growth stages in the flag leaf. Contents of chlorophyll (Chl), ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCO), and total soluble protein were initially higher and subsequently lower in penultimate than flag leaves. EC decreased RuBPCO protein content relative to soluble protein and Chl contents throughout the development of penultimate leaves. On the other hand, EC initially increased the RuBPCO:Chl and Chl a/b ratios, but later decreased them in flag leaves. In the flag leaves but not in the penultimate leaves, ET initially decreased initial and specific RuBPCO activities at ambient CO2 (AC) and increased them at EC. Late in leaf growth, ET decreased Chl contents under AC in both kinds of leaves, and had no effect or a positive one under EC. Thus the differences between the two kinds of leaves were due to resource availability, and to EC-increased allocation of resources to photon harvesting in the penultimate leaves, but to increased allocation to carboxylation early on in growth, and to light harvesting subsequently, in the flag leaves. and P. Pérez ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. Non-singular covers over monoid rings

Creator:
Bican, Ladislav
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
hereditary torsion theory, torsion theory of finite type, Goldie’s torsion theory, non-singular module, non-singular ring, monoid ring, precover class, and cover class
Language:
English
Description:
We shall introduce the class of strongly cancellative multiplicative monoids which contains the class of all totally ordered cancellative monoids and it is contained in the class of all cancellative monoids. If G is a strongly cancellative monoid such that hG ⊆ Gh for each h ∈ G and if R is a ring such that aR ⊆ Ra for each a ∈ R, then the class of all non-singular left R-modules is a cover class if and only if the class of all non-singular left RG-modules is a cover class. These two conditions are also equivalent whenever we replace the strongly cancellative monoid G by the totally ordered cancellative monoid or by the totally ordered group.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public