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The data on density of dilute solutions of urea (U) in ethylene diamine (EDA) with the molality from ∼0.018 to ∼0.39 mol·(kg solvent)−1were experimentally obtained between (288.15 and 328.15) K and at ambient pressure. The uncertainty in density measurements did not exceed 0.03 kg m–3. The standard (partial at infinite dilution) molar volumes, V2○, and expansibilities, Ep,2○, of U as a solute in EDA were computed. The unusual phenomenon of the thermally activated partial molar isobaric compaction of the solute (PMICS) caused by the presence of a negative sign at Ep,2○was discovered. The origin of this atypical volumetric effect in both the system under consideration and some other urea-containing amphiprotic media was discussed based on the thermodynamic approach including the Ben-Naim’s concept of the “relative affinity parameter”.

Densities of dilute solutions of urea (U) in tert-butylamine (t-BuNH2) with molalities being up to ∼0.023 mol·kg–1were measured at T= 278.15, 283.15, 288.15, 293.15, 298.15, and 303.15 K and p= 99.6 kPa. All experiments were carried out using a sealed U-tube vibrating densimeter. The total uncertainty in the density measurements did not exceed 0.03 kg·m–3. The standard (apparent at infinite dilution) molar volumes and expansibilities of U as a solute in t-BuNH2were computed. Similar to infinitely dilute solutions of U in methanol (MeOH) and tert-butanol (t-BuOH), the phenomenon of the so-called “negative partial molar expansibility” or “partial molar isobaric compaction of a solute” was found in the studied binary system. The mixed structural aggregate or “solvation complex” formed by a U molecule in the t-BuNH2medium becomes increasingly compact as the temperature rises because the solute-to-solvent affinity more and more noticeably prevails over the affinity of the solvent molecules for each other. In doing so, the stronger heterocomponent H-bonding leads to the marked increase in the compactness of solvation complexes formed in U solutions going from t-BuOH to t-BuNH2.

In a number of water use schemes (water and wastewater treatment), physicochemical treatment methods, in particular adsorption, have been successfully used. However, widespread adoption of these methods is hindered by the high cost of sorbents. One of the promising solutions to these problem of sorption treatment is the use of biochar. Due to its high specific surface area, well-developed porous structure, and surface functionality, biochar has been used as inexpensive adsorbent. The purpose of the laboratory experiments is to determine the sorption properties of biochar obtained from pine – sorption capacity, sorption rate, and purification effect – while removing organic contaminants from real paper mill wastewater. The sorption properties of biochar were studied under static and dynamic conditions, varying the size of the fractions, and processing time. The sorption characteristics of biochar of all the studied fractions were established and it was shown that the most effective sorbent in removing organic contaminants is the 1-biochar’s fraction of (sorption capacity of 11.9 mg of COD per of sorbent). The data obtained enable theoretically substantiate the presence of certain functional groups on the surface of the researched biochar, as well as to develop technological regimes for the treatment of natural and waste waters of a certain composition with its help.

Densities of urea (U) and tetramethylurea (TMU) solutions in formamide (FA) and water with a solute molality of up to ∼2 mol kg–1were measured at T= 288.15, 298.15, 308.15, 318.15, and 328.15 K and p= 99.6 kPa. All experiments were performed using a precision vibrating U-tube densimeter at measuring uncertainty not exceeding 0.03 kg m–3. Standard partial and excess molar volumes as well as volume-related parameters of solute–solute interactions for U and TMU in both solvents under comparison were computed. The derived results were discussed on the assumption that FA, like water or ethylene glycol (EG), is a solvent having a capability to form the spatial hydrogen-bonding network, inducing effects of solvophobic solvation. It was found that a structure-compression effect during the solvation of TMU in FA becomes somewhat enhanced with increasing temperature. In turn, the process of forming the “solvation complex” of U in FA is accompanied already by structure loosening at temperatures higher than T= 288 K. The same goes for both (EG + TMU) and (EG + U) systems, too, but the “loosening effect” in the last case appeared at T> 308 K only. Similarly to aqueous solutions, the temperature has a differentiating effect on trends of changing in both the standard partial molar expansibility of U and TMU and volume coefficients of the U–U and TMU–TMU pair interactions in FA as well as EG. The data obtained here confirm the fact that the solvophobity of TMU in water is markedly stronger pronounced than it occurs in FA and EG media. Herewith, the previous conclusion that, in a thermochemical sense, the solvation behavior of compared ureas in FA is more “waterlike” than in liquid EG is overall true for the solute TMU only.

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Nitrification, the oxidation of ammonia (NH3) via nitrite (NO2−) to nitrate (NO3−), is a key process of the biogeochemical nitrogen cycle. For decades, ammonia and nitrite oxidation were thought to be separately catalysed by ammonia-oxidizing bacteria (AOB) and archaea (AOA), and by nitrite-oxidizing bacteria (NOB). The recent discovery of complete ammonia oxidizers (comammox) in the NOB genus Nitrospira, which alone convert ammonia to nitrate, raised questions about the ecological niches in which comammox Nitrospira successfully compete with canonical nitrifiers. Here we isolate a pure culture of a comammox bacterium, Nitrospira inopinata, and show that it is adapted to slow growth in oligotrophic and dynamic habitats on the basis of a high affinity for ammonia, low maximum rate of ammonia oxidation, high growth yield compared to canonical nitrifiers, and genomic potential for alternative metabolisms. The nitrification kinetics of four AOA from soil and hot springs were determined for comparison. Their surprisingly poor substrate affinities and lower growth yields reveal that, in contrast to earlier assumptions, AOA are not necessarily the most competitive ammonia oxidizers present in strongly oligotrophic environments and that N. inopinata has the highest substrate affinity of all analysed ammonia oxidizer isolates except the marine AOA Nitrosopumilus maritimus SCM1 (ref. 3). These results suggest a role for comammox organisms in nitrification under oligotrophic and dynamic conditions.

Nitrification, the oxidation of ammonia via nitrite to nitrate, has always been considered to be a two-step process catalysed by chemolithoautotrophic microorganisms oxidizing either ammonia or nitrite. No known nitrifier carries out both steps, although complete nitrification should be energetically advantageous. This functional separation has puzzled microbiologists for a century. Here we report on the discovery and cultivation of a completely nitrifying bacterium from the genus Nitrospira, a globally distributed group of nitrite oxidizers. The genome of this chemolithoautotrophic organism encodes the pathways both for ammonia and nitrite oxidation, which are concomitantly activated during growth by ammonia oxidation to nitrate. Genes affiliated with the phylogenetically distinct ammonia monooxygenase and hydroxylamine dehydrogenase genes of Nitrospira are present in many environments and were retrieved on Nitrospira-contigs in new metagenomes from engineered systems. These findings fundamentally change our picture of nitrification and point to completely nitrifying Nitrospira as key components of nitrogen-cycling microbial communities.

Existing screening tools for HIV-Associated Neurocognitive Disorders (HAND) may lack the accuracy required for clinical use. We hypothesized that the diagnostic accuracy of the Montreal Cognitive Assessment (MoCA) as a screening tool for HAND might be improved with a stronger scoring methodology.

It is established that the eliminations of construction sand with the content of SiO2 about 70 wt. % and particle size less than 60 mk are suitable for the production of a foamglass-crystal material on the basis of the low-temperature frit, which was synthesized at the temperature 900 °C. The obtained foamglass-crystal material exceeds foamglass (by 3.0 times) and clayite (by 1.5 times) by strength and is characterized by low value of water absorption (0.1 %).

Genomewide DNA linkage analysis identified a susceptibility locus for intracranial aneurysm (IA) on chromosome 19q13 in the Finnish population, a region including the kallikrein gene cluster. We investigated the association of single nucleotide polymorphisms (SNPs) in the kallikrein gene cluster with IA in the Finnish population.

New step‐growth graft block copolymers were synthesized. These two‐sided comb copolymers consisted of a poly(amic ester) (PAE) backbone and pendant poly(propylene oxide) (PPO) grafts. The copolymers were made via a macromonomer approach, in which the 4,6‐bischlorocarbonyl isophthalic acid bis[poly(propylene oxide)] ester macromonomer was synthesized through the reaction of hydroxyl‐terminated PPO oligomers with pyromellitic dianhydride and oxalyl chloride. This macromonomer was subsequently used in step‐growth polymerization with comonomers 4,6‐bischlorocarbonyl isophthalic acid diethyl ester, 2,5‐bischlorocarbonyl terephthalic acid diethyl ester, and 2,2‐bis[4‐ (4‐aminophenoxy)phenyl] hexafluoropropane, and this yielded PPO‐co‐PAE graft copolymers. Accordingly, we report the synthesis and characterization of the PPO oligomer, the PPO macromonomer, and their corresponding PPO‐co‐PAE graft copolymers. Graft copolymers with PPO concentrations of 3–26 wt % were synthesized. These polymers were thermally cured to produce polyimide/PPO composites. The thermolysis of these polyimide/PPO composites yielded porous polyimide films with porosities ranging of 4–22.5%. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2266–2275, 2005

Luminescence, excitation of luminescence and absorption spectra of europium capronate crystals as well as vibrational IR and Raman spectra at 4.2, 77 and 293 K were obtained. Magnetic susceptibility measurements were carried out down to 1.7 K. Correlations between the spectral and magnetic properties and details of the structure of the title compound were studied. The crystal field parameters were calculated using the Stark splitting of the Eu³⁺ electronic levels. The oscillator strengths were evaluated. Changes in the spectra and magnetic susceptibility of Eu(C₅H₁₁COO)₃Phen with increasing temperature from 4.2 to 293 K proves transformation of the crystal lattice. The subtle splitting of bands in the regions of the ⁵D₀→⁷F₁ and ⁵D₀→⁷F₂ transitions was revealed. Several possible causes of this phenomenon, including resonant vibronic interactions and/or the possible effect of ion-pair interactions, are discussed.

After intratracheal administration of "empty" lecithin-cholesterol liposomes to rats it was found out twofold enhancement of the surfactant content with maximum on the 2nd-3rd day and with normalization to the control level by the 7th day. Phagocytic index of the alveolar macrophages was also increased. It was shown the change of the blast-transformation reaction of bronchoalveolar lavage and blood lymphocytes. Immune complexes content in bronchoalveolar lavage at different period of time after liposomes administration increased 1.5-2-fold. The natural killers (NK) activity of cells obtained from bronhoalveolar lavage and blood was enhanced 10 times and 2 times respectively. It is supposed that enhancement of lung surfactant phospholipid content is caused by substrate stimulation of type II alveolocytes activity. The stimulation of immunocompetent cells might be connected with imitation of bacterial attack by liposomes with proteins adsorbed on their surface.

Some microorganisms can use reduced compounds of molybdenum as energy sources for autotrophic growth. A culture of molybdenum-oxidizing bacteria was obtained by enrichment in a mineral-salts medium by using samples of oxidized molybdenum ore from a molybdenum deposit as inoculum. In laboratory experiments, powellite (CaMoO4) was obtained. The role of microorganisms in the geochemistry of molybdenum is discussed.

Electroinjection analysis is described and compared with electrophoretically mediated microanalysis and flow injection analysis. Mathematical models of electroinjection analysis and electrophoretically mediated microanalysis are presented. An analytical solution for the concentration of the product of a chemical reaction is derived and used for the discussion of the optimal regimes of analysis. Examples of the applications of electroinjection analysis and electrophoretically mediated microanalysis for the determination of Cr(VI) and Co(II) ions in water are presented.

Abstract: A gram-negative, non-motile, non-marine, nitrite-oxidizing bacterium was isolated from an enrichment culture initiated with a sample from a partially corroded area of an iron pipe of a heating system in Moscow, Russia. The cells were 0.9–2.2 μm0.2–0.4 μm in size. They were helical- to vibroid-shaped and often formed spirals with up to three turns 0.8–1.0 μm in width. The organism possessed an enlarged periplasmic space and lacked intracytoplasmic membranes and carboxysomes. The cells tended to excrete extracellular polymers, forming aggregates. The bacterium grew optimally at 39C and pH 7.6–8.0 in a mineral medium with nitrite as sole energy source and carbon dioxide as sole carbon source. The optimal nitrite concentration was 0.35 mM. Nitrite was oxidized to nitrate stoichiometrically. The doubling time was 12 h in a mineral medium with 7.5 mM nitrite. The cell yield was low; only 0.9 mg protein/l was formed during oxidation of 7.5 mM nitrite. Under anoxic conditions, hydrogen was used as electron donor with nitrate as electron acceptor. Organic matter (yeast extract, meat extract, peptone) supported neither mixotrophic nor heterotrophic growth. At concentrations as low as 0.75 g organic matter/l or higher, growth of nitrite-oxidizing cells was inhibited. The cells contained cytochromes of theb- andc-type. The G+C content of DNA was 56.90.4 mol%. The chemolithoautotrophic nitrite-oxidizer differed from the terrestrial members of the genusNitrobacter with regard to morphology and substrate range and equaledNitrospira marina in both characteristics. The isolated bacterium is designated as a new species of the genusNitrospira. Comparative analysis of 16S rRNA gene sequences revealed a moderate phylogenetic relationship toNitrospira marina, leptospirilla,Thermodesulfovibrio yellowstonii, “Magnetobacterium bavaricum”, and the isolate OPI-2. Initial evidence is given that these organisms represent a new phylum of the domain bacteria.

Migraine is a neurovascular disorder that affects over 1 billion people worldwide. Its widespread prevalence, and associated disability, have a range of negative and substantial effects not only on those immediately affected but also on their families, colleagues, employers, and society. To reduce this global burden, concerted efforts are needed to implement and improve migraine care that is supported by informed health-care policies. In this Series paper, we summarise the data on migraine epidemiology, including estimates of its very considerable burden on the global economy. First, we present the challenges that continue to obstruct provision of adequate care worldwide. Second, we outline the advantages of integrated and coordinated systems of care, in which primary and specialist care complement and support each other; the use of comprehensive referral and linkage protocols should enable continuity of care between these systems levels. Finally, we describe challenges in low and middle-income countries, including countries with poor public health education, inadequate access to medication, and insufficient formal education and training of health-care professionals resulting in misdiagnosis, mismanagement, and wastage of resources.