פרסומים

  

Garlic flowering and bulbing are prone to photo-thermal regulation during its annual cycle. As in many other geophytes, these pathways are parallel but competitive, and can be manipulated by the environment. Both flowering and bulbing are of paramount physiological value, and of great horticultural interest. We argue that, in bolting garlic, differential regulation of only one of the two pathways by pre-planting vernalization is unfeasible, and that garlic's response to cold shows an optimal curve. Within limits, long vernalization treatments have resulted in rapid development of ‘Reproductive and Bulbing Phenotype’ with fast leaf elongation, early transition of the apical meristem to the reproductive state, development of axillary buds, flowering and bulbing. Low temperatures trigger primary signaling components, thus modulating organogenesis even under a relatively short photoperiod. We therefore propose that under a suboptimal photoperiod, favorable temperatures could substitute the plant's requirements for photoperiod and signal for the meristem transition, flowering and bulbing. The optimum response of the studied genotype was obtained after vernalization of four weeks at 4 °C. No transition of the apical meristem was evident in plants exposed to only short or no vernalization, namely the apex remained vegetative. These plants continuously produced foliage leaves, thus forming a “Leafy Phenotype” which did not branch, bulb or flower. Comprehension of the plant's response to environment is expected to facilitate physiological manipulations on the production of either bulbs or true seeds in garlic. © 2018

In mental time travel (MTT) one is "traveling" back-and-forth in time, remembering, and imagining events. Despite intensive research regarding memory processes in the hippocampus, it was only recently shown that the hippocampus plays an essential role in encoding the temporal order of events remembered, and therefore plays an important role in MTT. Does it also encode the temporal relations of these events to the remembering self? We asked patients undergoing pre-surgical evaluation with depth electrodes penetrating the temporal lobes bilaterally toward the hippocampus to project themselves in time to a past, future, or present time-point, and then make judgments regarding various events. Classification analysis of intracranial evoked potentials revealed clear temporal dissociation in the left hemisphere between lateral-temporal electrodes, activated at ~100-300 ms, and hippocampal electrodes, activated at ~400-600 ms. This dissociation may suggest a division of labor in the temporal lobe during self-projection in time, hinting toward the different roles of the lateral-temporal cortex and the hippocampus in MTT and the temporal organization of the related events with respect to the experiencing self.

Cellular redox status affects diverse cellular functions, including proliferation, protein homeostasis, and aging. Thus, individual differences in redox status can give rise to distinct subpopulations even among cells with identical genetic backgrounds. Here, we have created a novel methodology to track redox status at single cell resolution using the redox-sensitive probe Grx1-roGFP2. Our method allows identification and sorting of sub-populations with different oxidation levels in either the cytosol, mitochondria or peroxisomes. Using this approach, we defined a redox-dependent heterogeneity of yeast cells and characterized growth, as well as proteomic and transcriptomic profiles of distinctive redox subpopulations. We report that, starting in late logarithmic growth, cells of the same age have a bi-modal distribution of oxidation status. A comparative proteomic analysis between these populations identified three key proteins, Hsp30, Dhh1, and Pnc1, which affect basal oxidation levels and may serve as first line of defense proteins in redox homeostasis. © Radzinski et al.

This volume presents the proceedings of the international conference “Theatre Cultures within Globalising Empires: Looking at Early Modern England and Spain”, held in 2012 as part of the ERC Advanced Grant Project Early Modern European Drama and the Cultural Net (DramaNet). Implementing the concept of culture as a virtual network, it investigates Early modern European drama and its global dissemination. The 12 articles of the volume – all written by experts in the field teaching in the United Kingdom, the USA, Russia, Switzerland, India and Germany – focus on a selection of English and Spanish dramas from the sixteenth and seventeenth centuries. Analysing and comparing motifs, formal parameters as well as plot structures, they discuss the commonalities and differences of Early modern drama in England and Spain.

Function of உவமை Comparison of similarity உவமை (upama in Sanskrit, simile in English) is a literary concept and technique found in literary theories found in every language that has literate poetry. The concept is based on the notion of similarity (ஒப்பு, ஒப்புமை) between two things. The verb from which these nouns are derived (ஒப்பிடு) means ‘compare’. Similarity between things is never total; it is always partial (ஒருபுடை ஒப்புமை). பேராசிரியர் (S 1) explains this with the example tiger-like warrior, which excludes from similarity having a tail, four legs etc. Similar features for comparison are selected not just by natural similarity; the cultural convention about the significance of a feature or some features of things plays a crucial role as well. Comparison of the beauty of a woman with the beauty of the bird parrot is specific to Tamil (may be, Indian) culture, but is unacceptable in European culture. So, acceptable and unacceptable உவமை is culture specific and consequently, language specific. This, however, does not rule out உவமைs that are universally acceptable.

Emotion as உவமப்பொருள் Relation with மெய்ப்பாடு Disparity between பொருள் and உவமை when உவமை is markedly upsized or downsized serves a function. It is a cue to look for the expression of emotion through உவமை. As உவமை conveys meaning, it also conveys emotion (மெய்ப்பாடு) when it is marked. The relation of மெய்ப்பாடு, which is a central element in the performance of drama (நாடக வழக்கு), to உவமை, the device to create meaning in poetry, is the reason, according to commentators (இளம்பூரணர் S 1), to place the chapter on the latter after the chapter on the former. Conveying emotion is a derived function of உவமை, whose primary function is conveying meaning. This is suggested by the phrase மெய்ப்பாடு எட்டன் வழி மருங்கு அறியத் தோன்றும் ‘will appear to make one realize the derivative sense, which is one of the eight மெய்ப்பாடுs’ (S 19). The subjects of ‘will appear’ are the upsizing (பெருமை) and downsizing (சிறுமை) of உவமை in the sutra and they are the instigators of the emotions, which appear derivatively. பேராசிரியர் understands வழிமருங்கு as ‘sometimes’ (that modifies the verb தோன்றும்; எட்டன் is the object of அறிய) and says that upsizing and downsizing of உவமை are not needed all the times to convey emotion through உவமை (அவை (i.e. பெருமையும் சிறுமையும்) பற்றாது மெய்ப்பாடு எட்டும்பற்றி வாளாதே (‘simply’) உவமம் வருதல் செவ்விது). He means that மெய்ப்பாடு does not need to உவமை be marked and its absence is the preferred way. In other words, பெருமை and சிறுமை are optional for உவமை to convey emotion. It does not necessarily deny the fact that expressing emotion by உவமை is not required in every instance.

In most materials, transport can be described by the motion of distinct species of quasiparticles, such as electrons and phonons. Strong interactions between quasiparticles, however, can lead to collective behaviour, including the possibility of viscous hydrodynamic flow. In the case of electrons and phonons, an electron-phonon fluid is expected to exhibit strong phonon-drag transport signatures and an anomalously low thermal conductivity. The Dirac semi-metal PtSn4 has a very low resistivity at low temperatures and shows a pronounced phonon drag peak in the low temperature thermopower; it is therefore an excellent candidate for hosting a hydrodynamic electron-phonon fluid. Here we report measurements of the temperature and magnetic field dependence of the longitudinal and Hall electrical resistivities, the thermopower and the thermal conductivity of PtSn4. We confirm a phonon drag peak in the thermopower near 14 K and observe a concurrent breakdown of the Lorenz ratio below the Sommerfeld value. Both of these facts are expected for an electron-phonon fluid with a quasi-conserved total momentum. A hierarchy between momentum-conserving and momentum-relaxing scattering timescales is corroborated through measurements of the magnetic field dependence of the electrical and Hall resistivity and of the thermal conductivity. These results show that PtSn4 exhibits key features of hydrodynamic transport.