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Given the large and increasing amount of urban, suburban, and exurban land use on Earth, there is a need to accurately assess net primary productivity (NPP) of urban ecosystems. However, the heterogeneous and dynamic urban mosaic presents challenges to the measurement of NPP, creating landscapes that may appear more similar to a savanna than to the native landscape replaced. Studies of urban biomass have tended to focus on one type of vegetation (e.g., lawns or trees). Yet a focus on the ecology of the city should include the entire urban ecosystem rather than the separate investigation of its parts. Furthermore, few studies have attempted to measure urban aboveground NPP (ANPP) using field-based methods. Most studies project growth rates from measurements of tree diameter to estimate annual ANPP or use remote sensing approaches. In addition, field-based methods for measuring NPP do not address any special considerations for adapting such field methods to urban landscapes. Frequent planting and partial or complete removal of herbaceous and woody plants can make it difficult to accurately quantify increments and losses of plant biomass throughout an urban landscape. In this study, we review how ANPP of urban landscapes can be estimated based on field measurements, highlighting the challenges specific to urban areas. We then estimated ANPP of woody and herbaceous vegetation over a 15-year period for Baltimore, MD, USA using a combination of plot-based field data and published values from the literature. Baltimore's citywide ANPP was estimated to be 355.8 g m

White-tailed deer (Odocoileus virginianus)–vehicle collisions (DVCs) are increasing as human and deer populations continue to grow. Deer harvest was implemented at Oak Ridge Reservation, Tennessee (ORR) in 1985 to reduce DVCs. We assessed the relationship between DVCs at ORR to deer harvest, road type, and habitat features (forest, field, water, and developed cover types) during 1986–2008 using Poisson regression analysis and Akaike Information Criterion modeling. We also evaluated DVC numbers for the city of Oak Ridge and ORR during 1975–2008 to examine the effects of moon phase, employee work-shift timing, and season on DVCs. From 1975 to 2008, 4,637 DVCs occurred in Oak Ridge and ORR, with monthly DVCs peaking each November. Most DVCs occurred at the start of the workday. Annual DVC totals peaked at 273 in 1985; deer harvest was then implemented and DVCs declined. No harvest occurred in 2001 and DVCs increased for the next 2 years. A model including harvest, road type and distance, development, and water features received full support for explaining DVC occurrence. Harvest in the previous year was positively related to DVCs, likely reflecting higher hunter success with higher deer density. Higher traffic volume and speed were positively related to DVCs. There was no effect of moon phase for all records combined; however, analysis by season and gender showed a positive relationship to collisions for male deer during the gestation period (1 Jan–14 May), which may have been associated with dispersal. We recommend continued deer harvest and driver education to reduce DVCs. © 2014 The Wildlife Society.

Background: The purpose of this double-blind, prospective, latin-square crossover randomised study was to examine the efficacy of a mouthrinse solution containing a combination of triclosan, amine fluoride and sodium fluoride on supragingival plaque regrowth compared to a placebo and a chlorhexidine solution. Methods: 12 volunteers refrained after professional oral prophylaxis from all mechanical hygiene measures for the following 96 h and rinsed instead cross-over in a randomised order with either chlorhexidine dicluconate (0.2%, positive control), a verum solution (0.5% amine fluoride, 0.028% sodium fluoride, 0.03% triclosan) or a placebo solution. The plaque index was assessed after 24 and 96 h (PI 1, PI 2) and the plaque area (PA) photographed and calculated after 96 h of undisturbed plaque regrowth. Moreover plaque samples were taken after 24 and 96 h and examined with the vital fluorescence technique to assess the vitality of the biofilm microbiota (VF 1, VF 2). Results: The amine-fluoride-triclosan solution reduced the clinical parameters (PI and PA) as well as the vitality of the plaque flora (VF) significantly when compared to the placebo solution. The verum reached a 36.5% (p

The bridging behavior and redox mechanisms of liquid crystalline octahedral iron(III) complexes (such as the anhydrous complex below) were studied in detail by polarization microscopy, DSC, and Mossbauer spectroscopy. We gained great insight into the changes in molecular structure, and describe here a new type of magnetic short-range order in liquid crystals.

Photochemistry of Aminoketones. XV. Photochemical Acyl Migration in N-Tosyl-β-aminovinyl-phenyl-ketones N-Tosyl-β-aminovinyl-phenyl-ketones 1a – i are prepared in good yields from β-chlorovinyl- phenyl-ketones by reaction with the sodium salts of tosyl amides in dry DMF at room temperature. In contrast to the relatively photostable N, N-dialkyl-β-aminovinyl-aryl-ketones the electronically excited 1 give irreversible chemical reactions within a few minutes. Among other not identified photoproducts the α-tosyl-β-aminovinyl-phenyl-ketones 2 were found. From the experimental results it is evident that the migration of the tosyl group prefers a radical-type two step reaction through an intermediate X/Y of a (1,5)-NO-tosylrearrangement.

N,N-Dialkylamides of 2-Hydroxy-2-phenyl-cyclopropan-1-carboxylic Acid – Photochemical Synthesis and Determination of the Structure Irradiation of N,N-dialkylamides of β-benzoylpropionic acid 2a, b in ether by n,π*-excitation leads to the corresponding amides of the hitherto unknown 2-hydroxy-2-phenyl-cyclo-propancarboxylic acid 3a, b, 4a, b. The photocyclization yields diastereomeric mixtures E:Z = 2.5–3:1. The determination of the relative configurations is based on the different tendency of dimerization of the E and Z diastereomers.

Sydnone Ethylenes. II. Electronic Interactions in 4-Styryl-sydnones An estimation of intramolecular donor/acceptor interactions in 4-styryl-sydnones can be made by the substituent increments Ztrans derived from the corresponding vinyl compounds and by the comparison of the u.v.-spectra of ω(E)-substituted styrols. Because of the different anisotropic effects of sydnone and aryl groups the chemical shifts of the ethylene protons are not suitable for this purpose. The observed and calculated u.v.-spectra show that the electronic excitation of 4-styryl-sydnones causes a strengthening of the sydnone donor effect and a decrease of the bond-order in the CC-region.

Sydnone Ethylenes. III. Chemical Reactions of Excited 4-Styryl-sydnones Dependent on the character of the substituents in the photo reactions of 4-styryl sydnones Z/E-isomerism competes with CO2-elimination. Excited p-nitrostyryl sydnones exhibit a relatively strong degradation of the bond order in the CC region. Their quantum yields of Z/E-isomerism are therefore much higher than those of compounds with p-substituents of lower acceptor effect. In these compounds the cleavage of the sydnone ring with elimination of carbon dioxide is favoured especially if a methyl group is in 3-position of the sydnone.

Sydnone lassen sich in 4-Position nach VILSMEIER-HAAK formylieren. N(3)-Methyl- und N(3)-(p-Anisyl)-sydnon-(4)-carbaldehyd werden mit Athoxycarbonylmethan-phosphonsaurediathylester nach HORNER und mit verschiedenen Arylmethylphosphoniumsalzen nach WITTIG in Gegenwart starker Basen stereoselektiv olefiniert. Im letzteren Fall tritt besonders in Abwesenheit von Lithiumkationen eine Z-Selektivitat auf, die auf eine elektronische Wechselwirkung zwischen dem Sydnonring und dem aromatischen Substituenten des Phosphin-ylids im ersten Reaktionsschritt zuruckgefuhrt wird. Die Konfigurationsbestimmung der resultierenden Z- und E-Sydnonathylene erfolgt an Hand der 1H-NMR- und IR-Spektren. Sydnone Ethylenes. I Stereoselective Synthesis of Sydnone Ethylenes from Sydnone Aldehydes Sydnones are formylated in 4-position by the VILSMEIER-HAAK reaction. N(3)-Methyl- and N(3)-(p-Anisyl)-sydnone-(4)-carboxaldehyde react stereoselectively to sydnone ethylenes with diethyl ethoxycarbonylmethanephosphonate by HORNER reaction and with arylmethylphosphonium salts by WITTIG reaction in the presence of strong bases. In the latter case, especially in the absence of lithium cations, Z-selectivity is observed which is explained by electronic interaction between the sydnone cyclus and the aromatic substituent of the phosphine ylid in the first step of the reaction. The configuration of the obtained Z- and E-sydnone ethylenes is determined by means of 1H-NMR- and IR-spectra.

α-Diphenylphosphinyl-phenylmethan-phosphonsaurediphenylester 1d reagiert mit aromatischen Aldehyden regiospezifisch unter Abspaltung der Phosphorylgruppe mit stark unterschiedlichen Ausbeuten zu α-Phosphinyl-stilben bzw. analogen Verbindungen 2. Dabei fallen in Abhangigkeit von der Grose des Restes R4 cis-trans-Gemische unterschiedlicher Zusammensetzung an. Bei kleinem Rest, wie z. B. Phenyl oder Pyridyl, entsteht fast ausschlieslich das trans-Isomere, bei grosem Rest, z.B. Chinolyl, steigt der cis-Anteil, bzw. das cis-Isomere wird zum Hauptprodukt. Die Selektion zwischen cis- oder trans-Konfiguration der Reaktionsprodukte wird bestimmt durch das unterschiedliche Ausmas der sterischen Hinderung in den cyclischen Ubergangszustanden. Die gleiche Reaktion mit 1b und Benzaldehyd ergibt kein P-substituiertes Stilben, sondern 1,2-Bis-(diphenylphosphinyl)-1,2-diphenyl-athan 3, dessen Bildungsmechanismus diskutiert wird. Synthesis of α-Phosphinyl-substituted Stilbenes and Related Compounds Diphenyl-(α-diphenylphosphinyl-phenylmethane)-phosphonate 1d regiospecifically reacts to α-phosphinyl-stilbene or to analogous compounds 2 with aromatic aldehydes under elimination of the phosphoryl group, with very different yields. Cis-trans-mixtures of various composition are formed in dependence on the size of the R4-moiety. The trans-product is preferred if R4 is a small substituent for instance phenyl or pyridyl, but with a large moiety for instance quinolyl, the cis-isomer becomes predominant. The relation between cis- or trans-configuration of the reaction products is determined by the different extent of steric hindrance in the cyclic intermediate states. The analogous reaction with 1b and benzaldehyde does not yield P-substituted stilbene but 1,2-bis-(diphenylphosphinyl)-1,2-diphenylethane 3. The mechanism of this reaction is discussed.

Bei der Umsetzung trivalenter P-Ester mit Chlormethan-phosphon-saurediathylester laufen ARBUZOV-Reaktion und Alkylierung des P-Esters etwa in gleichem Mase ab. Die Ausbeute an ARBUZOV-Produkt 3 ist masig, seine Reingewinnung schwierig. Bei der analogen Umsetzung mit Chlormethan-phosphonsaure-diphenylester ist die ARBUZOV-Reaktion eindeutig die Hauptreaktion, die in guten Ausbeuten Methylen-bis-P(O)-Verbindungen 3 mit ungleich substituierten P-Atomen ergibt. Die Einfuhrung eines Phenylrestes in die Chlormethyl-Gruppe begunstigt stark die Halogenubertragung auf das trivalente P-Atom als Konkurrenzreaktion zur ARBUZOV-bzw. besonders zur MICHAELIS-BECKER-Reaktion. Ein weiterer Syntheseweg fur Methylen-bis-P(O)-Verbindungen besteht in der „Acylierung” methylenaktiver P(O)-Verbindungen durch trivalente P-Chloride mit nachfolgender Oxydation. In speziellen Fallen kann dieser Weg der ARBUZOV-Reaktion ausbeutemasig uberlegen sein.

Synthesis of trans-4-Diphenylphosphinyl Stilbenes The reaction of 4-tolyl-diphenylphosphine oxide with N-bromosuccinimide results in 4-diphenylphosphinyl benzylbromide 5 which can be easily converted to (4-diphenylphosphinyl)-benzyl triphenylphosphonium bromide 6 and (4-diphenylphosphinyl)-benzyl diphenylphosphine oxide 7, respectively. In the presence of strong bases 6 and 7 react with aromatic aldehydes 8 to the 4-diphenylphosphinyl substituted stilbenes 1. The yields depend on the nature of base and solvent. The trans configuration of 1 is determined by i.r. and 1H-n.m.r. measurements.

ortho-P(O)-substituierte Phenole 4 sind im Gegensatz zu offenkettigen Phosphoryl-enolen 1 durch Spaltung der Phenol-alkyl-ather gut zuganglich und als Studienobjekte fur die gegenseitige Beeinflussung der P O- und der OH-Gruppe in 1.2-Position einer CC-Doppelbindung geeignet. Rf(DC)-Werte deuten darauf hin, das die Phenole 4 in Losung bei ausreichender Basizitat des Phosphoryl-O-Atoms Wasserstoffbruckenbindungen PO H–O ausbilden, wahrend stark elektronenziehende P-Substituenten die Beteiligung der PO-Gruppe unwahrscheinlich machen. δOH- und Pka-Werte zeigen, das in Dimethylsulfoxid nur im ersten Fall (Phosphinoxide 4a–g) PO HO-Brucken existieren, wahrend bei Phosphonsaure-arylestern 4i–k Addukte mit DMSO-Molekulen gebildet werden. Fur diese Differenzierung sind in erster Linie induktive Substituenten-effekte verantwortlich. Die UV-Spektren deuten lediglich einen geringen konjugativen Beitrag von P-Phenylsubstituenten an. Hydrogen Bonds in Solutions of Ortho Phosphoryl Substituted Phenols In contrast to open-chained phosphoryl-enols 1 the ortho-P(O)-substituted phenols 4 may be conveniently obtained by cleavage of phenol alkylethers. Rf-values (TLC) demonstrate that the phenols 4 exhibit PO HO hydrogen bonds in solution if the basizity of the phosphoryl O-atom is sufficient. Electronwithdrawing P-substituents lower the probability of this interaction. δOH and Pka data demonstrate that in dimethylsulfoxide only phosphinoxides 4a–g give PO HO bridges. Arylesters of phosphonic acids 4i–k add DMSO-molecules via SO … HO hydrogen bonds. This difference is mainly a result of inductive effects. UV-spectra refer to a probably small contribution of P-phenyl substituents to conjugation.

Diphenylphosphinyl-methan-phosphonsaure-diphenylester 1d reagiert in Benzol und in Gegenwart geeigneter starker Basen mit Aldehyden regiospezifisch zu entsprechend β-substituierten Athylen-diphenylphosphinoxiden 4 in praparativ befriedigenden Ausbeuten. Durch Analyse der Signalfolge fur das Athylenproton HB im 1H-NMR-Spektrum des ABX-Spinsystems wird fur die isolierten Reinprodukte 4 die trans-Konfiguration sichergestellt. In ungunstigen Fallen gelingt die Separierung des HB-Signals nur durch Verschiebungsreagentien. Fur die Selektion cis-oder trans-Konfiguration der Reaktionsprodukte 4 wird eine sterische Hinderung im Ubergangszustand des zweiten Reaktionsschrittes als mitbestimmend diskutiert. Preparation and 1H-N.M.R. Spectroscopic Investigation of β-Substituted Ethylene Diphenylphosphine Oxides The diphenyl ester 1d of diphenylphosphinyl-methanephosphonic acid in benzene reacts regiospecifically with aldehydes, in presence of strong bases, to β-substituted ethylene diphenylphosphine oxides 4. The yields are satisfactory on a preparative scale. The ABX type H-n.m.r. spectra of compounds 4 were analysed. The isolated pure products 4 exhibit trans configuration, characterized by the specific signal sequence of the ethylene proton HB which in some cases could be separated by use of shift reagents. The cis or trans configuration of compounds 4 can be referred partially to steric hindrance in the transition state of the second reaction step.

The kinetics of the antibody response in cattle have been analyzed and the following results were obtained: 1A single administration of proteins to cattle given intravenously or as alum-precipitated antigen evoked a concurrent synthesis of γM- and γG-antibodies as reflected in the serum 7 days following immunization. Employing the antigen binding capacity method for assaying antibody activity, the γG-antibody collected 7 days after immunization exceeded by several times that of the γM-class. 2The γG-antibody response as reflected in serum and colostrum three weeks after primary stimulation showed a marked increase when compared with their respective antibody levels formed earlier. The colostral 19 S antibody, composed of 19 S γG-globulin and the easily discernible γM-component was also increased and surpassed by several times the γM-antibody level in a 3-weeks serum. 3When colostrum was fed to the newborn calf, the γG-antibody appeared to be absorbed quantitatively by the intestinal tract, whereas the high molecular weight globulins (19 S) were transmitted much less efficiently. This might indicate that some sort of selective absorption occurred between different classes of immunoglobulins. 4Kinetic studies of the secondary response demonstrated that in cattle serum an anamnestic reaction exists for γM-antibody as well as for γG-antibody. 5The dissociation of the 19 S molecules from serum and colostrum by reduction and alkylation produces little effect on the antigen binding capacity of the monomer subunits obtained. 6The kinetic characteristics of serum and colostral 19 S- and γG-antibodies were studied by measurement of the association rates. γM-Antibodies present in serum 7 days following antigenic challenge had a higher affinity for protein antigens than γG-antibody molecules. There is considerable evidence, however, that the affinity of the γG-antibody for the antigenic determinants increased progressively with time after immunization.

Durch isobaren Abbau bei 20, 100, bzw. 200 Torr werden die niedern Hydrate der Alaune MeIMeIII(SO4)2 · 12 H2O (mit MeIII = Cr, Al und MeI = K, NH4, Rb, Cs) hergestellt. Aus Rontgenpulverdiagrammen werden Isotypiebeziehungen abgeleitet und als Blockdiagramm wiedergegeben. The lower hydrates of the alums MeIMeIII(SO4)2 · 12 H2O (MeIII = Cr, Al and MeI = K, NH4, Rb, Cs) are prepared by decomposition at pressures of 20, 100 and 200 torr, respectively. X-ray powder diagrams indicating isotypic relations are diagramatically represented.

Methan-bis-(phosphonsaure-diathylester) reagiert mit Aldehyden in Gegenwart der aquimolaren Menge Kalium-tert.-butylat zu 2-substituierten Athylen-1-phosphonsaure-diathylestern in praparativem Masstab. Durch Analyse der Signalfolge fur die Vinylprotonen im 1H-NMR-Spektrum wird die trans-Konfiguration der isolierten Athylen-phosphonsaure-ester sichergestellt. Fur die Selektion cis- oder trans-Konfiguration der Reaktionsprodukte wird eine sterische Hinderung im Ubergangszustand des zweiten Reaktionsschrittes als entscheidend angesehen.