The effect of some anticholinesterase agents and of hemicholinium on the amount of substance P in rabbit brain and gut

Résumé Les substances anticholinestérasiques s'avèrent capables de réduire la concentration en substance P du cerveau et de l'intestin du lapin. Cependant l'hémicholinium No 3 augmente la concentration de la substance P de l'intestin et diminue celle du cerveau.     

Antigenic correlation between rat brain synaptic vesicles and rat bone marrow B lymphocytes

Summary Rabbit anti-rat brain synaptic vesicle serum reacted with thymocytes and B lymphocytes in cytotoxicity and immunofluorescence assays. Quantitative absorption analysis revealed that this antiserum contained antibodies specific for antigenic determinants on the surface membrane of a subpopulation of rat bone marrow B lymphocytes.This work was supported by the Republic of Serbia Research Fund, Belgrade.     

Diminution de radiosensibilité du rat adulte en hypothermie profonde

Summary Using an appropriate technique, we put adults rats of both sexes under deep hypothermy (rectal temperature of 14–15°C). Under these conditions, the respiration and the cardiac rhythm are definitely slowed down.(1) Rats irradiated in a state of deep hypothermy with lethal doses of 800 and 900 r of X-rays, are partially protected. 50% of these animals survived more than 30 days, whereas all control animals died after 17 days.(2) The same degree of protection is obtained if the cooling is made in the presence of oxygen or under an air pressure of 1.25 atmosphere.     

Examination of cannabis resin by means of ferric chloride test

Résumé Les auteurs ont étudié les colorations obtenues par la résine de chanvre avec le chlorure ferrique et les ont exprimées numériquement en indices de FeCl₃ permettant de caractériser certains types de chanvre; l'indice s'accroît avec la teneur en acide canabidiolique.     

Alterations of free amino acids concentrations in cat brain induced by rapid eye movement sleep deprivation

Résumé La concentration de certains acides aminés libres au niveau du cerveau chez le chat change sous l'influence de la privation élective du sommeil paradoxal. Ces changements pourraient s'expliquer par l'augmentation d'excitabilité nerveuse associée à la privation élective du sommeil paradoxal.     

Weight of rat embryos after X-ray irradiation

Résumé Les embryons de rat ont été irradiés par les rayons X à la dose de 100 r du cinquième au dixième jour de la gestation. Tous les embryons ont été fixés au boulin le quinzième jour de la gestation et ont été pesés après le passage dans l'alcool.Les embryons irradiés, comme c'est déjà connu, sont plus légers que les témoins, mais il y a aussi une différence significative entre les divers groupes irradiés.     

Controlling cavity reflectivity with a single quantum dot

Solid-state cavity quantum electrodynamics (QED) systems offer a robust and scalable platform for quantum optics experiments and the development of quantum information processing devices. In particular, systems based on photonic crystal nanocavities and semiconductor quantum dots have seen rapid progress. Recent experiments have allowed the observation of weak and strong coupling regimes of interaction between the photonic crystal cavity and a single quantum dot in photoluminescence. In the weak coupling regime, the quantum dot radiative lifetime is modified; in the strong coupling regime, the coupled quantum dot also modifies the cavity spectrum. Several proposals for scalable quantum information networks and quantum computation rely on direct probing of the cavity-quantum dot coupling, by means of resonant light scattering from strongly or weakly coupled quantum dots. Such experiments have recently been performed in atomic systems and superconducting circuit QED systems, but not in solid-state quantum dot-cavity QED systems. Here we present experimental evidence that this interaction can be probed in solid-state systems, and show that, as expected from theory, the quantum dot strongly modifies the cavity transmission and reflection spectra. We show that when the quantum dot is coupled to the cavity, photons that are resonant with its transition are prohibited from entering the cavity. We observe this effect as the quantum dot is tuned through the cavity and the coupling strength between them changes. At high intensity of the probe beam, we observe rapid saturation of the transmission dip. These measurements provide both a method for probing the cavity-quantum dot system and a step towards the realization of quantum devices based on coherent light scattering and large optical nonlinearities from quantum dots in photonic crystal cavities.     

Distribution of the meadow lizard in Europe and its realized ecological niche model

One of the most interesting but elusive members of the European herpetofauna is the meadow lizard (Darevskia praticola). It is a small, ground dwelling, predominantly forest living lacertid, for which many ecological and biological data are still missing. Moreover, at least for the western part of the species range (south-eastern Europe) its distribution and environmental associations are insufficiently known, likely due to difficulties in detection even with intensive field sampling. Here, we complemented the available literature records with our personal observations and explored the effects of environmental factors shaping the species ecological niche and distribution in Europe using the ecological niche modelling approach from Maxent software. The new records of the meadow lizard fill a gap in its known distribution. The most suitable habitats are in central and eastern Serbia, south-western Romania, and central, southern and south-western Bulgaria. Mean temperature of the coldest quarter, vegetation and slope had the strongest effect in defining the meadow lizard’s ecological niche. Niche suitability increased with the increase in forest cover and slope, while the temperature showed a bell-shaped response with a rather narrow tolerance range for temperature. Contrary to expectations, precipitation seemed to have no contribution to the species occurrence. Ecological niche model performance increased with a higher resolution of predictor variables despite the lower number of available occurrence records, although the slope variable had a greater predictive power when calculated at a lower resolution. Interestingly, high resolution vegetation variables (30 m) were able to show some level of habitat fragmentation, which likely resulted from deforestation. Overall, our results epitomize the effects of limited sampling on the biogeography inference of elusive species while having significant repercussions on conservation priorities and management of the species.     

Application of species-richness estimators for the assessment of earthworm diversity

This paper includes the current knowledge of earthworm distribution and richness in the central part of the Balkans, in the state of Serbia. The work is based on data obtained from fieldwork in the western part of Serbia. The aim is to follow a methodological and theoretical framework for the application of species-richness estimators in earthworm biodiversity research. We have evaluated the performance of various estimation techniques to assess the different species-richness estimators in EstimateS. The following estimators (EstimateS 8.2) were used to extrapolate species richness beyond our own data: ACE, ICE, Chao 1, Chao 2, Jackknife 1, Jackknife 2, Bootstrap, and Michaelis–Menten richness estimator. The Chao 2 and Jackknife 2 richness estimators were considered most appropriate to predict the number of earthworm species and can serve to provide a quantitative basis for assessing long-term changes in species richness.