A black-box approach to the construction of metal-radical multispin systems and analysis of their magnetic properties.

An interaction of M(hfac)2 (M = Mn or Ni) with N-(bis(4,4,5,5-tetramethyl-3-oxido-1-oxyl-4,5-dihydro-1H-imidazol-2-yl)methylene)-2-methyl-propan-2-amine oxide (a nitronyl nitroxide diradical with the >C[double bond, length as m-dash]N(O)-tert-Bu coupler) was investigated under various conditions. It was found that prolongation of reaction time caused transformation of the initial diradical into new diradicals with the unique >C[double bond, length as m-dash]N-OH coupling unit and formation of binuclear Mn(ii) and Ni(ii) complexes, which were characterized by X-ray diffraction analysis. The resulting binuclear heterospin complexes have a complicated magnetic structure with six paramagnetic centers and a number of exchange interaction channels between them, as well as between neighboring complexes. To adequately describe the magnetic properties of these complexes, high-level ab initio calculations of their electronic structure and parameters of the spin-Hamiltonian were carried out. The accuracy of the conventional broken-symmetry density functional theory approach in the calculation of the exchange interaction parameters was also verified.

Host and symbiont intraspecific variability: The case of Paramecium calkinsi and "Candidatus Trichorickettsia mobilis".

Newly isolated strains of the ciliate Paramecium calkinsi and their cytoplasmic bacterial endosymbionts were characterized by a multidisciplinary approach, including live observation, ultrastructural investigation, and molecular analysis. Despite morphological resemblance, the characterized P. calkinsi strains showed a significant molecular divergence compared to conspecifics, possibly hinting for a cryptic speciation. The endosymbionts were clearly found to be affiliated to the species "Candidatus Trichorickettsia mobilis" (Rickettsiales, Rickettsiaceae), currently encompassing only bacteria retrieved in an obligate intracellular association with other ciliates. However, a relatively high degree of intraspecific divergence was observed as well, thus it was possible to split "Candidatus Trichorickettsia" into three subspecies, one of which represented so far only by the newly characterized endosymbionts of P. calkinsi. Other features distinguished the members of each different subspecies. In particular, the endosymbionts of P. calkinsi resided in the cytoplasm and possessed numerous peritrichous flagella, although no motility was evidenced, whereas their conspecifics in other hosts were either cytoplasmic and devoid of flagella, or macronuclear, displaying flagellar-driven motility. Moreover, contrarily to previously analyzed "Candidatus Trichorickettsia" hosts, infected P. calkinsi cells frequently became amicronucleate and demonstrated abnormal cell division, eventually leading to decline of the laboratory culture.

Structural specifics of light-induced metastable states in copper(II)-nitroxide molecular magnets.

Although light-induced magnetostructural switching in copper(II)-nitroxide molecular magnets Cu(hfac)2L(R) has been known for several years, structural characterization of metastable photoinduced states has not yet been accomplished due to significant technical demands. In this work we apply, for the first time, variable-temperature FTIR spectroscopy with photoexcitation to investigate the structural specifics of light-induced states in the Cu(hfac)2L(R) family represented by (i) Cu(hfac)2L(Me) comprising two-spin copper(II)-nitroxide clusters, and (ii) Cu(hfac)2L(Pr) comprising three-spin nitroxide-copper(II)-nitroxide clusters. The light-induced state of Cu(hfac)2L(Me) manifests the same set of vibrational bands as the corresponding thermally-induced state, implying their similar structures. For the second compound Cu(hfac)2L(Pr), the coordination environment of copper(II) is similar in light- and thermally-induced states, but distinct differences are found for packing of the peripheral n-propyl substituent of nitroxide. Thus, generally the structures of the corresponding thermally- and light-induced states in molecular magnets Cu(hfac)2L(R) might differ, and FTIR spectroscopy provides a useful approach for revealing and elucidating such differences.

[At the background of ecological parasitology].

The data on scientific and teaching activities of A. A. Filipchenko, doctor of medicine and scientist-parasitologist, one of the founders of ecological parasitology in Russia is presented in this article. His fate and participation in the formation of this biological discipline were concealed for a long time. One of the reasons for this situation is the destruction of the scientist in 1938 during the course of mass repressions performed by Soviet State against its own citizens.

[Economic evaluation and rationale for human health risk management decisions].

The priority task of human health maintenance and improvement is risk management using the new economic concepts based on the assessment of potential and real human risks from exposure to poor environmental factors and on the estimation of cost-benefit and cost-effectiveness ratios. The application of economic tools to manage a human risk makes it possible to assess various measures both as a whole and their individual priority areas, to rank different scenarios in terms of their effectiveness, to estimate costs per unit of risk reduction and benefit increase (damage decrease).

[Economic evaluation and rationale for human health risk management decisions].

The priority task of human health maintenance and improvement is risk management using the new economic concepts based on the assessment of potential and real human risks from exposure to poor environmental factors and on the estimation of cost-benefit and cost-effectiveness ratios. The application of economic tools to manage a human risk makes it possible to assess various measures both as a whole and their individual priority areas, to rank different scenarios in terms of their effectiveness, to estimate costs per unit of risk reduction and benefit increase (damage decrease).

[Evaluation of exposure of the Moscow population to ambient air pollution by carcinogenic substances].

The rapid growth of motor transport in Moscow has led to a substantial increase in the volumes of pollutant emissions into the city's air. As of 2007, the motor transport fleet of the city approximated 3 million units annually consuming about 5 million tons of motor fuel. Carcinogenic substances, such as formaldehyde and benzene, are supervised in the ambient air of Moscow. To evaluate their adverse effect on human health, carcinogenic risks are calculated from their annual average concentrations. The levels of total carcinogenic risks from the impact of the average concentrations of formaldehyde and benzene in the period 2005 to 2007 in all areas correspond to the maximum permissible (alarm) risk that requires measures to improve ambient air. According to the results of the investigation, health promotion measures are recommended to the Government of Moscow.

[Evaluation of Moscow population exposure to ambient air pollution by carcinogenic substances].

The carcinogenic risk to the Moscow population exposed to ambient air pollutants, such as benzene and formaldehyde, discharged by motor transport has been assessed. The ways of lowering the negative impact of motor transport on the urban environment are considered.

[Monitoring of the medicodemographic situation in Moscow].

There has been recently a trend in declining mortality rates in all population groups. Higher birth rates and lower mortality have been responsible for a reduction in natural population loss in Moscow. At the same time, 14 of the 123 Moscow municipal districts show a positive natural population growth largely due to higher birth rates. Better social and economic living conditions, the effective activities of health care bodies and sanitary and epidemiological well-being services of the city have caused recent positive changes in the demographic situation.

[The hygienic requirements for the organization of prehouse areas to create good living conditions for the population].

The paper considers the organization of prehouse areas, their improvement, and the adequate space of these prehouse territories to create good living conditions for the population. It has been found that the assessment of the existing town-planning situation in Moscow and the evaluation of the adopted functional zoning in the general town planning scheme for the city and administrative districts, and decision-making on the population's complaints require the estimation of the balance of a residential territory to develop normative requirements for this problem when considering the preconstruction proposals on location of variously purposeful projects in more detail, by analyzing the town-planning situation.

[Population health risk assessment on designing the transport streams of Moscow].

The population health risk was assessed in the microdistricts adjacent to a future road interchange area in Moscow. Its possible negative impact was studied by many parameters, including the carcinogenic risk. Evidence is provided to a need for planning decisions on the optimization and reduction of the possible risk.

[Impact of chemical ambient air pollution in Moscow on its population's health].

The ambient atmosphere of Moscow is appraised as unbeneficial to the health of the population, that of children and adolescents in particular. Motor transport is a powerful source of the ambient air pollution of Moscow. The average annual level of atmospheric pollution in 2008 is considered to be moderate. Scientific-and-practical studies using the risk assessment methodology also suggest that the ambient air in Moscow is the leading habitat posing a carcinogenic and non-carcinogenic risk to Muscovites' health.

Suppression of high-p{T} neutral pion production in central Pb+Pb collisions at sqrt[S{NN}]=17.3 GeV relative to p+C and p+Pb collisions.

Neutral pion transverse momentum spectra were measured in p+C and p+Pb collisions at sqrt[S{NN}]=17.4 GeV at midrapidity (2.3 less than or approximately equal eta{lab} less than or approximately equal 3.0) over the range 0.7 less than or approximately equal p{T} less than or approximately equal 3.5 GeV/c. The spectra are compared to pi{0} spectra measured in Pb+Pb collisions at sqrt[S{NN}]=17.3 GeV in the same experiment. For a wide range of Pb+Pb centralities (N{part} less than or approximately equal 300), the yield of pi{0}'s with p{T} greater than or approximately equal 2 GeV/c is larger than or consistent with the p+C or p+Pb yields scaled with the number of nucleon-nucleon collisions (N{coll}), while for central Pb+Pb collisions with N{part}greater than or approximately equal 350, the pi{0} yield is suppressed.

Nocodazole inhibits macronuclear infection with Holospora obtusa in Paramecium caudatum.

Holospora obtusa is a Gram-negative bacterium inhabiting the macronucleus of the ciliate Paramecium caudatum. Experimental infection with H. obtusa was carried out under nocodazole treatment. Nocodazole has been shown to cause disassembly of the cytoplasmic microtubules radiating from the cytopharynx and postoral fibers in P. caudatum. Treatment with this drug did not prevent the ingestion of both prey bacteria and H. obtusa, but it reduced the phagosome number and affected cyclosis. In situ hybridization revealed infectious forms of this endobiont very close to the macronucleus, but never inside it. These results indicate that disassembly of microtubules does not impair transportation of the infectious forms of H. obtusa in the cytoplasm, but that it completely blocks the invasion of the nucleus by the bacteria.

Spirostomum spp. (Ciliophora, Protista), a suitable system for endocytobiosis research.

Among ciliate genera, only Paramecium and Euplotes species have been studied extensively as host organisms of bacterial endocytobionts. In this article, we show that members of the genus Spirostomum may also serve as a suitable system for endocytobiosis research. Two strains of Spirostomum minus (Heterotrichea, Ciliophora) collected in Germany and Italy, respectively, were found to harbor different types of bacterial infections. Bacteria of various sizes and shapes were observed in the cytoplasm or in the nuclei of the ciliates. The bacteria in the cytoplasm were either surrounded by a peribacterial membrane or lay naked. One of the bacterial species was found in the vicinity of the contractile fibrillar system (myonemes) of the ciliates. In rare cases, another type of bacteria was observed associated with mitochondria. The macronuclei of both the Italian and the German strains were crowded with endocytobionts. The endonuclear bacteria in the two S. minus strains differed with respect to their cytoplasmic structures but they were of similar size and both were rod shaped. According to the results of in situ hybridization, the endonuclear bacteria of the Italian strain belong to the subgroup of alphaproteobacteria, whereas the bacteria associated with the fibrillar system appeared to be gram-positive bacteria with high G+C content. While both the German and the Italian strains were found to permanently maintain their endocytobionts, they were at least partly colonized by different bacteria. This is taken as an indication that geographically separated populations of ciliates may be stably infected by different endocytobionts, possibly due to different ecological conditions. For S. minus and S. ambiguum a total of 7 different bacterial endocytobionts have now been recorded. We recommend the members of the genus Spirostomum as a suitable system for endocytobiosis research.

Interferometry of direct photons in central 208Pb + 208Pb collisions at 158A GeV.

Two-particle correlations of direct photons were measured in central 208Pb+208Pb collisions at 158A GeV. The invariant interferometric radii were extracted for 100