NASA Astrophysics Data System (ADS)
Asmafiliz, Nuran; ?lter, Elif Ece; I??klan, Muhammet; K?l?ç, Zeynel; Tercan, Bar??; Çaylak, Nagihan; Hökelek, Tuncer; Büyükgüngör, Orhan
2007-04-01
The reactions of hexachlorocyclotriphosphazatriene, N 3P 3Cl 6, with N 2O 2-donor type coronands (diaza-crown ethers) 1- 3 afford novel monotopic 4- 7 and ditopic 8- 10spiro-crypta phosphazenes, respectively. It has been observed that the reactions of N 3P 3Cl 6 with 1 equivalent amount of coronands 1- 3 yield only monotopic spiro-derivatives, while three equivalent amount of coronands 2 and 3 give dominantly ditopic dispiro-crypta-phosphazene skeletons. On the other hand, the 31P NMR spectrum of 8 indicates that the ditopic spiro-ansa phosphazene 10 is present besides the ditopic dispiro derivative 8. Unexpectedly, the reaction of 6 with excess amount of pyrrolidine leads to the formation of geminal product 7. The 31P NMR spectra of 4, 5, 6 and 10 indicate that all of these compounds have anisochronism. The structures of 5, 8 and 9 have been determined by X-ray crystallography. The relative radii of macrocyclic hole sizes of 5, 8 and 9 are calculated from the crystallographic results. The relationships between the exocyclic NPN and endocyclic NPN bond angles of the analogous compounds with ?P-shifts of NPN phosphorus atoms have been discussed. Thus, sums of the bond angles around the nitrogen atoms are in the range of [342.7(2)°-354.4(2)°], showing that the nitrogen atoms have pyramidal configurations. The pyramidal configuration gives rise to stereogenic properties. The salient spectroscopic features [FTIR, 1H, 13C, 31P NMR, HETCOR (for 5 and 7) and MS] of all the compounds are presented.
NASA Astrophysics Data System (ADS)
Bilge, Selen; K?l?ç, Zeynel; Çaylak, Nagihan; Hökelek, Tuncer
2004-11-01
The condensation reactions between hexachlorocyclotriphosphazatriene ( 1), N 3P 3Cl 6, and dibenzo-diaza crown ethers ( 2 and 3) afforded two novel spiro-crypta-phosphazene derivatives ( 4 and 5). Compounds ( 4 and 5) have been characterized by elemental analyses, FTIR, 1H-, 13C-, 31P NMR, HETCOR and MS. The structure of crypta-phosphazene ( 5) has been determined crystallographically. Compounds ( 4 and 5) are the first examples of the crypta-phosphazene derivatives. The 31P NMR spectra of compounds ( 4 and 5) indicate that both of the compounds have anisochrony, possibly because of the stereogenic nitrogen atoms. In compound ( 5), the pyramidal geometries of four spiro-cyclic nitrogen atoms give rise to stereogenic properties. The sum of the bond angles around N4, N4A, N5 and N5A nitrogens are 346.2(4), 348.8(3), 347.1(3) and 345.8(4)°, respectively. Compound ( 5) crystallizes in the P21 space group with a=11.831(2), b=21.108(2), c=11.936(1) Å, ?=102.70(1)°, V=2907.9(6) Å 3, Z=2 and Dx=1.442 g cm -3. The absolute structure was determined successfully. There are two molecules in the asymmetric unit. The structure consists of a non-centrosymmetric, non-planar phosphazene ring with a bulky dibenzo-diaza crown ether side group.
NASA Astrophysics Data System (ADS)
Dal, Hakan; Süzen, Yasemin
2007-08-01
The condensation reaction of { N-[(2-hydroxyphenylmethyl)amino]-4,6-dimethylpyridine} ( 2), which is a reduction product of 1, with trimer N 3P 3Cl 6 affords partially a substituted spiro-cyclic phosphazene derivative ( 3). The fully substituted phosphazenes ( 4 and 5) have also been obtained from the reactions of 3 with the excess of pyrrolidine and morpholine. The characterizations and spectral investigations of these compounds have been made by elemental analyses, FTIR, 1H-, 13C-, 31P NMR, correlation spectroscopy (COSY), heteronuclear chemical shift correlation (HETCOR), heteronuclear multiple-bond correlation (HMBC) and mass spectroscopy (MS). The salient features of spectral data of these compounds have been discussed.
Uslu, Aylin; Güvenalt?n, Sener
2010-11-28
In this study, hexachlorocyclotriphosphazene, N(3)P(3)Cl(6) (cylotriphosphazene), was reacted with hydrophilic and hydrophobic groups to synthesize amphiphilic phosphazene derivatives (4-12). Cylotriphosphazene was reacted triethylene glycol monomethyl ether (TEGME), dipropylene glycol monomethyl ether (DPGME), diethylene glycol monobutyl ether (DEGBE), (1 : 3 mole proportion) in the presence of sodium hydride and using tetrahydrofuran (THF) as solvent at -60 °C. Three isomers (nongeminal cis-2,4,6 (1a-3a); nongeminal trans-2,4,6 (1b-3b); geminal 2,2,4 (1c-3c)) were isolated from the reaction of hexachlorocyclotriphosphazatriene (trimer) (1) with TEGME, DPGME and DEGBE. The substitution reactions of cis-tris isomers (1a-3a) with 4-amino butyric acid, 5-amino valeric acid and 6-amino hexanoic acid were separately done to provide amphiphilic phosphazenes (4-12). All compounds were characterized by using elemental analysis, (31)P NMR and mass spectroscopy. Thermosensitive properties of compounds were studied. The compounds (4-12) were soluble in both water and organic media that shows they are amphiphilic molecules. Concentration-dependent LCST (Lower Critical Solution Temperature) behaviours of new compounds (4-12) were measured in water. Compounds 7, 9, 11 and 12 exhibited a reversible and thermosensitive phase transition in aqueous medium, from soluble to insoluble states. PMID:20938539
Technology Transfer Automated Retrieval System (TEKTRAN)
Conventional pad-dry-cure (non-scCO2) and supercritical carbon dioxide (scCO2) application methods were investigated to study the effectiveness of a phosphazene derivative as a flame retardant on cotton fabric. 1,1',4,5-tetrahydrotrispiro[1,3,2-diazaphosphole-2,2'-[1,3,5,2,4,6]triazatriphosphinine-4...
Ring-closing metathesis reactions of terminal alkene-derived cyclic phosphazenes.
Kumar, Dheeraj; Singh, Nem; Keshav, Karunesh; Elias, Anil J
2011-01-01
The first examples of ring-closing metathesis (RCM) reactions of a series of terminal alkene-derived cyclic phosphazenes have been carried out. The tetrakis-, hexakis-, and octakis(allyloxy)cyclophosphazenes (NPPh(2))(NP(OCH(2)CH=CH(2))(2))(2) (1), N(3)P(3)(OCH(2)CH=CH(2))(6) (2), and N(4)P(4)(OCH(2)CH=CH(2))(8) (3) and the tetrakis(allyloxy)-S-phenylthionylphosphazene (NS(O)Ph)[NP(OCH(2)CH=CH(2))(2)](2) (4) were prepared by the reactions of CH(2)=CHCH(2)ONa with the cyclophosphazenes (NPPh(2))(NPCl(2))(2), N(3)P(3)Cl(6), and N(4)P(4)Cl(8) and the S-phenylthionylphosphazene (NS(O)Ph)(NPCl(2))(2). The reactions of 1-4 with Grubbs first-generation olefin metathesis catalyst Cl(2)Ru=CHPh(PCy(3))(2) resulted in the selective formation of seven-membered di-, tri-, and tetraspirocyclic phosphazene compounds (NPPh(2))[NP(OCH(2)CH=CHCH(2)O)](2) (5), N(3)P(3)(OCH(2)CH=CHCH(2)O)(3) (6), and N(4)P(4)(OCH(2)CH=CHCH(2)O)(4) (7) and the dispirocyclic S-phenylthionylphosphazene compound (NS(O)Ph)[NP(OCH(2)CH=CHCH(2)O)](2) (8). X-ray structural studies of 5-8 indicated that the double bond of the spiro-substituted cycloalkene units is in the cis orientation in these compounds. In contrast to the reactions of 1-4, RCM reactions of the homoallyloxy-derived cyclophosphazene and thionylphosphazene (NPPh(2))[NP(OCH(2)CH(2)CH=CH(2))(2)](2) (9) and (NS(O)Ph)[NP(OCH(2)CH(2)CH=CH(2))(2)](2) (10) with the same catalyst resulted in the formation of 11-membered diansa compounds NPPh(2)[NP(OCH(2)CH(2)CH=CHCH(2)CH(2)O)](2) (11) and (NS(O)Ph)[NP(OCH(2)CH(2)CH=CHCH(2)CH(2)O)](2) (13) and the intermolecular doubly bridged ansa-dibino-ansa compounds 12 and 14. The X-ray structural studies of compounds 11 and 13 indicated that the double bonds of the ansa-substituted cycloalkene units are in the trans orientation in these compounds. The geminal bis(homoallyloxy)tetraphenylcyclotriphosphazene [NPPh(2)](2)[NP(OCH(2)CH(2)CH=CH(2))(2)] (15) upon RCM with Grubbs first- and second-generation catalysts gave the spirocyclic product [NPPh(2)](2)[NP(OCH(2)CH(2)CH=CHCH(2)CH(2)O)] (16) along with the geminal dibino-substituted dimeric compound [NPPh(2)](2)[NP(OCH(2)CH(2)CH=CHCH(2)CH(2)O)(2)PN][NPPh(2)](2) (17) as the major product. The dibino compound 17, upon reaction with the Grubbs second-generation catalyst, was found to undergo a unique ring-opening metathesis reaction, opening up the bino bridges and partially converting to the spirocyclic compound 16. PMID:21114315
Harrup, Mason K; Rollins, Harry W
2013-11-26
An additive comprising a phosphazene compound that has at least two reactive functional groups and at least one capping functional group bonded to phosphorus atoms of the phosphazene compound. One of the at least two reactive functional groups is configured to react with cellulose and the other of the at least two reactive functional groups is configured to react with a resin, such as an amine resin of a polycarboxylic acid resin. The at least one capping functional group is selected from the group consisting of a short chain ether group, an alkoxy group, or an aryloxy group. Also disclosed are an additive-resin admixture, a method of treating a wood product, and a wood product.
NASA Technical Reports Server (NTRS)
Paciorek, K. L.; Harris, D. H.; Ito, T. I.; Kratzer, R. H.
1980-01-01
The synthesis of a specific phosphazene diamine was optimized, other phosphorus-containing diamines were prepared, and their effect upon certain characteristics of epoxy resins, prepared via reaction with MY 720, in particular, char yield at elevated temperatures was evaluated. The synthesis of the phosphazene diamine resulting from the interaction of methylenedianline with 4,4'-bis(diphenylphosphino)biphenyl was simplified into a one step process giving 77 percent yield of the pure product. Using this procedure, a related diamine containing bis(diphenylphosphino)methane was obtained in a 70 percent yield. Preparation of another class of phosphorus containing amines based upon p-aminophenyldiphenyl-phosphine was unsuccessful; the inability to produce p-aminophenylithlum was responsible for this failure. Seven epoxy resins employing Araldite MY 720, diaminodiphenylsulfone, and two of the phosphorus containing diamines were prepared, characterized, and their char yield capacity at elevated temperatures assessed. Based on these investigations, the resins containing phosphorus appear to exhibit significantly better char formation characteristics than materials hardened using conventional amines, without impairing the other properties measured.
Novel fire-resistant polyphosphazenes and phosphazene-containing polymers
NASA Astrophysics Data System (ADS)
Taylor, Jonathan Paul
A functionalized polyphosphazene, poly[bis(carboxylatophenoxy)phosphazene], was blended with a structural polyurethane via reactive mixing of the polymer with diisocyanate and diol prepolymers. The thermal stabilities of the resultant foams were analyzed by thermogravimetric analysis (TGA). Both qualitative and quantitative flame tests indicated an increase in flame resistance at loadings of 20 wt% and above. Methods for the incorporation of phosphate and phosphonate units into the side groups of phosphazenes are described and evaluated. Halogenated organophosphates were used as the phosphorylating agents and were allowed to react with hydroxyl- or lithio-functionalized phosphazenes. Well defined phosphorylated cyclic trimers were synthesized from the hydroxyl-functionalized precursors, and these were examined as flame retardant additives to polystyrene. The thermal stabilities of the high polymers made by this route were analyzed by TGA. Ring-opening metathesis polymerization (ROMP) of phosphazene-functionalized norbornenes was demonstrated with the use of the Grubbs catalyst. This allowed the incorporation of alkoxy-, fluoroalkoxy-, and aryloxy-derived cyclic phosphazenes as side groups linked to the organic polymer backbone. The polymers were obtained in moderate yields with the properties being dependent on the side groups present and on the molecular weight. In addition, cyclooctenes and norbornenes with cyclic phosphazene side units bearing trifluoroethoxy or phenoxy groups were polymerized via ROMP using a ruthenium based initiator. The same monomers were also copolymerized with 90--99 mole percent of cyclooctene, norbornene, dicyclopentadiene, or exo,exo-5,6-bis(methoxycarbonyl)-7-oxabicyclo[2.2.1]hept-2-ene. The presence of as little as 2 mol% of the cyclic phosphazene in the copolymers dramatically reduced the combustibility. Poly(diphenyl-p-styrylphosphine) and copolymers of diphenyl- p-styrylphosphine with either styrene or methyl methacrylate were functionalized via the Staudinger reaction with phosphazene cyclic trimers bearing an azide side group. The phosphazene rings bore trifluoroethoxy or phenoxy groups as the cosubstituents. All the polymers were characterized by multi-nuclear NMR, GPC, and DSC. The mechanisms of flame retardance were studied with TGA and OI methods. The chemical structures of the polymer backbone and of the phosphazene side groups affected the thermal stability and fire resistance of the final materials.
NASA Astrophysics Data System (ADS)
Hakan, Dal; Serap, Safran; Yasemin, Süzen; Tuncer, Hökelek; K?l?ç, Zeynel
2005-10-01
The condensation reactions of { N-[(2-hydroxyphenylmethyl)amino]-methylpyridines (5-8) with trimer, N 3P 3Cl 6, have been afforded partially substituted novel spiro-cyclic phosphazene derivatives ( 9- 12) ( Scheme 1). Compounds ( 9- 12) have been characterized by elemental analyses, FTIR, 1H-, 13C-, 31P-NMR, HETCOR, and MS. The structure of the spiro-cyclic phosphazene ( 9) has been examined crystallographically. It crystallizes in the P2 1/n space group with a=10.7906(10) Å, b=8.5625(17) Å, c=21.187(5) Å, ?=91.298(12)°, V=1957.1(6) Å 3, Z=4 and Dx=1.660 g cm -3. The structure consists of a non-planar phosphazene ring with a bulky methylpyridinyl and a benzo-fused spiro-cyclic side group. The six-membered spiro-cyclic ring has a twist-boat conformation.
Phosphazene membranes for gas separations
Stewart, Frederick F.; Harrup, Mason K.; Orme, Christopher J.; Luther, Thomas A.
2006-07-11
A polyphosphazene having a glass transition temperature ("T_{g}") of approximately -20.degree. C. or less. The polyphosphazene has at least one pendant group attached to a backbone of the polyphosphazene, wherein the pendant group has no halogen atoms. In addition, no aromatic groups are attached to an oxygen atom that is bound to a phosphorus atom of the backbone. The polyphosphazene may have a T_{g }ranging from approximately -100.degree. C. to approximately -20.degree. C. The polyphosphazene may be selected from the group consisting of poly[bis-3-phenyl-1-propoxy)phosphazene], poly[bis-(2-phenyl-1-ethoxy)phosphazene], poly[bis-(dodecanoxypolyethoxy)-phosphazene], and poly[bis-(2-(2-(2-.omega.-undecylenyloxyethoxy)ethoxy)ethoxy)phosphazene]. The polyphosphazene may be used in a separation membrane to selectively separate individual gases from a gas mixture, such as to separate polar gases from nonpolar gases in the gas mixture.
NASA Astrophysics Data System (ADS)
?lter (neè Kaya), E. E.; Çaylak, N.; I??klan, M.; Asmafiliz, N.; K?l?ç, Z.; Hökelek, T.
2004-07-01
The condensation reactions between trimer, N 3P 3Cl 6, and diamines, 2 and 4 and {1-{ N-[1-(2-hydroxynaphthylmethyl)aminomethylidene]}-2(1H)-naphthalenone, 3, yielded the new spiro-cyclic- ( 5 and 8) and the novel spiro-phosphazene ( 7) derivatives, respectively. The fully substituted phosphazene ( 6) was also obtained from the reaction of 5 with the excess of pyrrolidine. Compounds ( 4- 8) have been characterized by elemental analyses, FTIR, 1H-, 13C-, 31P-NMR, HETCOR, COSY and MS. The structure of crypta-phosphazene, 8, has been examined crystallographically. Compound 8 is the first example of the crypta-phosphazene derivatives. The 31P-NMR spectra of compounds 7 and 8 indicate that, both of the compounds have anisochronism because of the stereogenic centers. The pyramidal geometry of two spiro-cyclic nitrogen atoms in compound 8, gives rise to stereogenic property. The sums of the bond angles around N 4 and N 5 nitrogens are 350.6(2) and 349.6(3)°, respectively. Compound 8 crystallizes in the triclinic space group P overline1 with a=8.798(3), b=10.498(3) and c=15.689(4) Å; ?=91.35(2), ?=103.39(4) and ?=102.88(4)°; V=1369.9(7) Å 3, Z=2 and D x=1.491 g cm -3. It consists of a non-centrosymmetric, non-planar phosphazene ring with a bulky dibenzo-diazacrown etheric side group.
Allen, Charles A. (Idaho Falls, ID); Grey, Alan E. (Idaho Falls, ID); McCaffrey, Robert R. (Milford, MA); Simpson, Brenda M. (Idaho Falls, ID); Stone, Mark L. (Idaho Falls, ID)
1994-01-01
A composite is produced by first coating a reinforcing material with an inorganic phosphazene compound and then polymerizing the phosphazene compound so as to confer superior thermal, physical and chemical resistance qualities to the composite.
Allen, Charles A.; Grey, Alan E.; McCaffrey, Robert R.; Simpson, Brenda M.; Stone, Mark L.
1994-05-03
A composite is produced by first coating a reinforcing material with an inorganic phosphazene compound and then polymerizing the phosphazene compound so as to confer superior thermal, physical and chemical resistance qualities to the composite.
Carboranylmethylene-substituted phosphazenes and polymers thereof
NASA Technical Reports Server (NTRS)
Allcock, H. R.; Scopelianos, A. G. (inventors)
1984-01-01
Carboranylmethylene-substituted cyclophosphazenes are described which can be thermally polymerized into carboranylmethylene-substituted phosphazene polymers. The polymers are useful as thermally stable coatings. Also, due to the characteristics of these polymers in acting as a ligand for transition metals, metalocarboranylmethylene phosphazene polymers are described which can act as immobilized catalyst systems, and are electrically conductive and superconductive.
Allen, C.A.; Grey, A.E.; McCaffrey, R.R.; Simpson, B.M.; Stone, M.L.
1990-12-31
The object of the invention is to provide a composite material comprised of phosphazene polymer. A feature of phosphazene-containing composites is their superior stiffness, thermal stability, and hardness which is lacking in more typical composite constituents. An advantage of using phosphazene composites is a wider range of applications, including uses in harsh environments. Another object of the present invention provides a method for producing phosphazene-containing composite materials through a pultrusion process. In brief, these and other objects are achieved by a composite produced by first coating a reinforcing material with an inorganic phosphazene compound and then polymerizing the phosphazene compound so as to confer superior thermal, physical and chemical resistance qualities to the composite. 2 figs., 6 tabs.
Hybrid phosphazene anodes for energy storage applications
Eric J. Dufek; Mark L. Stone; Kevin L. Gering; Frederick F. Stewart; David Jamison; Aaron D. Wilson; Lucia M. Petkovic; Mason K. Harrup; Harry W. Rollins
2014-12-01
The use of hybrid cyclic phosphazene polymer/graphite anodes, where the phosphazene serves as distributed loci for Li deposition, has been investigated. Capacity within the hybrid system was found to occur reversibly in distinct regions. At the most positive voltages, above 0.06 V vs Li/Li+, the capacity was associated mostly with Li+ intercalation into graphite. In the most negative region, deposition of Li within the polymer was the predominate mechanism. A transitional region is inferred by the data whereby bulk aggregation or clustering of Li atoms occurs in proximity to the phosphazene sites that then serve as a template for more widespread population of Li within the anode at higher voltages, akin to a nucleation process. In full cells with a mixed oxide cathode, controlling the extent of Li deposition by limiting the charging voltage to 4.45 V enabled repeated cycling with no loss in capacity. Capacities as high as 183 mAh g-1 have been achieved for systems containing as little as 10% graphite while retaining coulombic efficiencies of 98% over 50 cycles. This level of cycling equates to the deposition of 7.4 Li per cyclic phosphazene.
Nonlinear optical properties of linear chain phosphazenes, (PN)x
NASA Astrophysics Data System (ADS)
Chandra Jha, Prakash; Krishnan, Anu; Das, Puspendu K.; Ramasesha, S.
2002-08-01
The correlated Pariser-Parr-Pople model Hamiltonian for interacting pi-electrons is employed for calculating frequency dependent linear polarizability as well as first and second hyperpolarizabilities of linear chain phosphazenes (-PDouble_BondN-)x (x=3-6). The model parameters for phosphorus and nitrogen are obtained by comparing the theoretical excitation energies with experimental spectra of the known phosphazene systems. The optical gap of the phosphazene oligomers extrapolates to 3.7 eV compared to 2.8 eV of their organic analogs, namely, the polyenes. The linear polarizability of the phosphazene systems are comparable to those of the polyenes. However, the third harmonic generation coefficients are smaller at the same excitation energies. The power law exponent for the third harmonic generation coefficient in phosphazenes is also much smaller than that in polyenes. The second harmonic generation coefficients of the phosphazenes are smaller than those of the push-pull polyenes. Introduction of terminal push-pull groups on phosphazenes does not significantly improve the second harmonic generation response of these systems.
Craven, Michael; Yahya, Rana; Kozhevnikova, Elena; Boomishankar, Ramamoorthy; Robertson, Craig M; Steiner, Alexander; Kozhevnikov, Ivan
2013-01-14
Polyoxometalate-phosphazene salt aggregates comprising cyclophosphazene cations are highly efficient catalysts for environmentally benign biphasic oxidations with hydrogen peroxide. These catalysts self-assemble in situ simply by mixing commercial Keggin POMs and readily available phosphazenes. PMID:23135481
Spectroscopic studies on poly(diorgano)phosphazenes, a new class of medical polymers
NASA Astrophysics Data System (ADS)
Su?kowski, W.; Su?kowska, A.; Kireev, V.
1995-04-01
Poly(diorgano)phosphazenes belong to a relatively new class of polymeric materials. Generally, poly(dichloro)phosphazene is used as a starting material in the reactions involving the chlorine atom replacement by different nucleophilic organic substituents. Such a reaction scheme is accepted also for the synthesis of poly(dialkoxy)phosphazenes. ? R = C 2H 5; C 4H 9; C 6H 13; C 8H 17; C 12H 25; CH 2C 6H 5 The presence of trace of chlorine in poly(diorgano)phosphazenes in many cases leads to the substantial changes of their physico-chemical properties and limits application possibilities of this class of polymers. The influence of the substitution rate of chlorine atoms in poly(dichloro)phosphazenes on physicochemical properties of these polymers is shown for poly(dialkoxy)phosphazenes samples and of poly(dibutoxy)phosphazene fractions having similar molecular weights and obtained in two different synthesis.
Cil, Erol; Tanyildizi, Mehmet Ali; Ozen, Furkan; Boybay, Mustafa; Arslan, Mustafa; Gorgulu, Ahmet Orhan
2012-06-01
A new spirocyclophosphazene, 2,2-bis(2-formylphenoxy)-4,4,6,6-bis[spiro(2',2?-dioxy-1'-1?-biphenylyl)]cyclotriphosphazene (3), was obtained from the reaction of 2,2-dichloro-4,4,6,6-bis[spiro(2',2?-dioxy-1'-1?-biphenylyl)]cyclotriphosphazene (2) with 2-hydroxybenzaldehyde. New phosphazene derivatives bearing Schiff base and dioxybiphenyl groups have been synthesized by the reactions of 3 with different amines. The structures of the compounds were defined by elemental analysis, IR, (1) H, (13) C, and (31) P NMR spectroscopy. All the synthesized compounds were screened for their antibacterial activity against both types of Gram-negative and Gram-positive bacteria. The most potent antibacterial compound of this series was compound 12 which has the low MIC value of 3.75-0.9375?µg/mL. Both minimal inhibitory concentrations (MIC) and inhibition zones were determined in order to monitor the efficacy of the synthesized compounds. New compounds were also screened for anticonvulsant, CNS depressant, and sedative-hypnotic activity. After i.p. injection to mice at doses of 30, 100, and 300?mg/kg body weight phosphazenes were examined in the maximal electroshock-induced seizure (MES) and subcutaneous pentylenetetrazole (scPTZ) induced seizure models in mice. The neurotoxicity was assessed using the rotorod method. Compounds 4, 5, and 11 were found to be active in both MES screen and scPTZ screen at 0.5?h. All except 12 showed more than 44% decrease in locomotor activity after 1?h of compound administration via actophotometer screen. CNS-depressant activity screened with the help of the forced swim method resulted in some potent compounds. Except for 7 and 12 other tested compounds were found to exhibit potent CNS depressants activity as indicated by increased immobility time. PMID:22415712
Phosphazenes: efficient organocatalysts for the catalytic hydrosilylation of carbon dioxide.
Courtemanche, Marc-André; Légaré, Marc-André; Rochette, Étienne; Fontaine, Frédéric-Georges
2015-04-01
Phosphazene superbases are efficient organocatalysts for the metal-free catalytic hydrosilylation of carbon dioxide. They react with CO2 to form the respective phosphine oxides, but in the presence of hydrosilanes, CO2 can be selectively reduced to silyl formates, which can in turn be reduced to methoxysilanes by addition of an extra loading of silanes. Activities reach a TOF of 32 h(-1) with a TON of 759. It is also shown that unexpectedly, N,N-dimethylformamide can reduce CO2 to a mixture of silyl formates, acetals and methoxides in the absence of any catalyst. PMID:25791523
NASA Astrophysics Data System (ADS)
Tümer, Yasemin; Asmafiliz, Nuran; K?l?ç, Zeynel; Hökelek, Tuncer; Yasemin Koç, L.; Aç?k, Leyla; Yola, Mehmet Lütfi; Solak, Ali Osman; Öner, Ya?mur; Dündar, Devrim; Yavuz, Makbule
2013-10-01
The gradually Cl replacement reactions of spirocyclic mono (1 and 2) and bisferrocenyl cyclotriphosphazenes (3-5) with the potassium salt of 4-hydroxy-3-methoxybenzaldehyde (potassium vanillinate) gave mono (1a-5a), geminal (gem-1b-5b), non-geminal (cis-1b, cis-5b and trans-2b-5b), tri (1c-5c) and tetra-substituted phosphazenes (1d-5d). Some phosphazenes have stereogenic P-center(s). The chirality of 4c was verified using chiral HPLC column. Electrochemical behaviors were influenced only by the number of ferrocene groups, but not the length of the amine chains and the substituent(s). The structures of the new phosphazenes were determined by FTIR, MS, 1H, 13C and 31P NMR, HSQC and HMBC spectral data. The solid-state structures of cis-1b and 4d were examined by single crystal X-ray diffraction techniques. The twelve phosphazene derivatives were screened for antimicrobial activity and the compounds 5a, cis-1b and 2c exhibited the highest antibacterial activity against G(+) and G(-) bacteria. In addition, it was found that overall gem-1b inhibited the growth of Mycobacterium tuberculosis. The compounds 1d, 2d and 4d were tested in HeLa cancer cell lines. Among these compounds, 2d had cytotoxic effect on HeLa cell in the first 48 h. Moreover, interactions between compounds 2a, gem-1b, gem-2b, cis-1b, 2c, 3c, 4c, 5c, 1d, 2d and 4d, and pBR322 plasmid DNA were investigated.
Design, synthesis, and molecular recognition of phosphazene materials
NASA Astrophysics Data System (ADS)
Sunderland, Nicolas Jean
2000-08-01
This thesis represents several innovative approaches in the modification of polymers and solid-state hosts in order to obtain novel microstructures and properties. The first approach involves the use of cyclotriphosphazenes, a versatile class of hosts that generate tunnel clathrate adducts. Tris(o-phenylenedioxy)cyclotriphosphazene was found to form hexagonal host-guest inclusion adducts (clathrates) with the polymers: cis-1,4-polybutadiene, trans-1,4-polyisoprene, polyethylene, poly(ethylene oxide) and polytetrahydrofuran. Single crystal X-ray diffraction studies of both the polyethylene and poly(ethylene oxide) inclusion adduct revealed the presence of individual polymer chains extended along tunnel-like voids within the host lattice. Tris(o-phenylenedioxy)cyclotriphosphazene can entrap and separate various polymers and small molecules within its tunnels based on their microstructure, molecular weight, and end-group functionality. Inclusion adducts with various polymers show a preferential inclusion for the polymer that will best stabilize the hexagonal structure of the host. Separations based on end-groups show preferential inclusion of the species with the more hydrophobic end-groups. Polymers and small molecule hydrocarbons with higher molecular weights are preferentially included within the tunnel compared to analogues with lower molecular weights. The synthesis and inclusion properties of a new clathration host, tris(3,6-dimethylphenylenedioxy)cyclotriphosphazene, is described. The guest-free structure has a triclinic unit cell. The dioxane inclusion adduct crystallizes in a monoclinic system. The guest occupies a cage-like void located between the phosphazene rings. The poly(tetramethylene oxide) adduct crystallizes in a hexagonal system, with the guest located in tunnels created along the c-axis. Adduct formation also with tetrahydrofuran, methylene chloride, polyethylene and cis-polybutadiene. Modification of polymer properties is investigated by using a Staudinger reaction to attach cyclic phosphazene trimers bearing azide groups to phosphorus(III) atoms pendent to an organic polymer or co-polymer backbone. Diphenyl- p-styrylphosphine was polymerized via free radical or anionic methods and subsequently reacted with N3P3(OCH2CF 3)5(N3) and N3P3(OC 6H5)(N3). Fire retardance is improved these homopolymers, and also for polystyrene and poly(methyl methacrylate) co-polymers after reaction with the azide cyclic trimers. The ability to control the molecular weight and architecture of poly[bis(methoxyethoxy)ethoxy)phosphazene], a known solid polymer electrolyte, allows for a systematic study of the effect of molecular weight and architecture on conductivity. The mechanism of ion transport in these linear and star-branched systems is discussed.
Homogeneous nucleophilic radiofluorination and fluorination with phosphazene hydrofluorides.
Mathiessen, Bente; Jensen, Andreas T I; Zhuravlev, Fedor
2011-07-01
A series of phosphazenium hydrofluorides, P(1)(tBu)·[(18/19)F]HF, P(1)(tOct)·[(18/19)F]HF, P(2)(Et)·[(18/19)F]HF, and P(4)(tBu)·[(18/19)F]HF, was synthesized. The radioactive phosphazenium [(18)F]hydrofluorides were obtained by the one-step formation and trapping of gaseous [(18)F]HF with the respective phosphazene bases. The [(19)F] isotopomers were prepared from the corresponding phosphazene bases and Et(3)N·3HF. Under the design of experiment (DoE)-optimized conditions, P(2)(Et)·HF and P(4)(tBu)·HF fluorinated alkyl chlorides, bromides, and pseudohalides in 76-98% yield, but gave lower yields with iodides and electron-deficient arenes. DoE models showed that fluorination can be performed in glass vessels, and that the reactivity of P(2)(Et)·HF and P(4)(tBu)·HF is dominated by solvent polarity but is insensitive to water to at least 2 equiv. In contrast, P(1)(tBu)·HF and P(1)(tOct)·HF were unstable towards autofluorolysis. DFT calculations were performed to rationalize this finding in terms of diminished steric bulk, higher Parr's electrophilicity, and chemical hardness of P(1)(R)H(+). The corresponding radiofluorination reaction gave no valid DoE model but displayed similar substrate scope. High specific activity and excellent radiochemical yields with various pseudohalides (81-91%) suggest that the proposed radiofluorination methodology can complement the current [(18)F]KF/Kryptofix methods, particularly in the areas for which nonpolar reaction conditions are required. PMID:21626586
Control of Chemical, Thermal, and Gas Transport Properties in Dense Phosphazene Polymer Membranes.
Christopher J. Orme; Frederick F. Stewart; Mark L. Stone; Mason K. Harrup; Thomas A. Luther; Eric S. Peterson
2005-10-01
Polyphosphazenes are hybrid polymers having organic pendant groups attached to an inorganic backbone. Phosphazene polymers can be tailored to specific applications through the attachment of a variety of different pendant groups to the phosphazene backbone. Applications for which these polymers have proven useful include solid polymer electrolytes for batteries and fuel cells, as well as, membranes for gas and liquid separations. In past work, phosphazene polymers have been synthesized using mixtures of pendant groups with differing chemical affinities. Specific ratios of hydrophobic and hydrophilic pendant groups were placed on the phosphazene backbone with a goal of demonstrating control of solubility, and therefore chemical selectivity. In this work, a series of phosphazene homo-polymers were synthesized having varying amounts of hydrophobic and hydrophilic character on each individual pendant group. Polymers were synthesized having a hydrophilic portion next to the polymer backbone and the hydrophobic portion on the terminal end of the pendant group. The effects of these combined hydrophobic/hydrophilic pendant groups on polymer morphology and gas transport properties are presented. The following data will be addressed: thermal characterization, pure gas permeability on seven gases (Ar, H2, O2, N2, CO2, and CH4 ), and ideal selectivity for the gas pairs: O2/N2, H2/CO2, CO2/H2, CO2/CH4 and CO2/N2.
Jaffredo, Cédric G; Carpentier, Jean-François; Guillaume, Sophie M
2012-11-23
Basic organocatalysts of the guanidine (1,5,7-triazabicyclo[4.4.0]dec-5-ene, TBD), amidine (1,8-diazabicyclo[5.4.0]-undec-7-ene, DBU), and phosphazene (2-tert-butylimino-2-diethylamino-1,3-dimethylperhydro-1,3,2diazaphosphorine, BEMP) type do effectively polymerize ?-butyrolactone (BL). Poly(3-hydroxybutyrate)s (PHBs) with controlled molecular features, that is, controlled molar masses, narrow molar mass distributions, and well-defined functional end groups are thus formed at 60 °C from bulk monomer, with M(n,NMR) up to 21 500 g mol(-1). The formation of ?,?-guanidine/amidine/phosphazene,crotonate functionalized PHBs, as demonstrated by NMR, SEC, and MALDI-ToF mass spectrometry analyses, mechanistically suggests the formation of N-acyl-?,?-unsaturated propagating species that originate from 1:1 guanidine/amidine/phosphazene:BL adducts. PMID:22887774
Unsaturated Phosphazenes as Co-Solvents for Lithium-Ion Battery Electrolytes
Mason K Harrup; Harry W. Rollins; David K. Jamison; Eric J Dufek; Kevin L Gering; Thomas A Luther
2014-07-01
This paper covers the synthesis and use of a related family of cyclic phosphazene solvents containing terminal unsaturations. A brief synopsis on the synthesis and purification of these compounds is given. Data will be presented that covers physical and chemical properties of the phosphazenes as well as the properties when blended at various level with representative organic carbonate baseline solvents. Cycling data will be presented using commercially available electrode couples (LRMR/C) as well as studies focusing on cell performance at early lifetime as well as after repeated cycles. Conclusions regarding the effect of the unsaturated phosphazene compounds and their interaction with various alkyl carbonates, and their effect on cell performance will be presented.
Automated solid-phase radiofluorination using polymer-supported phosphazenes.
Mathiessen, Bente; Zhuravlev, Fedor
2013-01-01
The polymer supported phosphazene bases PS-P?(tBu) and the novel PS-P?(PEG) allowed for efficient extraction of [¹?F]F? from proton irradiated [¹?O]H?O and subsequent radiofluorination of a broad range of substrates directly on the resin. The highest radiochemical yields were obtained with aliphatic sulfonates (69%) and bromides (42%); the total radiosynthesis time was 35-45 min. The multivariate analysis showed that the radiochemical yields and purities were controlled by the resin load, reaction temperature, and column packing effects. The resins could be reused several times with the same or different substrates. The fully automated on-column radiofluorination methodology was applied to the radiosynthesis of the important PET radiotracers [¹?F]FLT and [¹?F]FDG. The latter was produced with 40% yield on a 120 GBq scale and passed GMP-regulated quality control required for commercial production of [1¹?F]FDG. The combination of compact form factor, simplicity of [¹?F]F? recovery and processing, and column reusability can make solid phase radiofluorination an attractive radiochemistry platform for the emerging dose-on-demand instruments for bedside production of PET radiotracers. PMID:23999726
A Study of Novel Hexavalent Phosphazene Salts as Draw Solutes in Forward Osmosis
Mark L. Stone; Aaron D. Wilson; Mason K. Harrup; Frederick F. Stewart
2013-03-01
Two novel multi-valent salts based on phosphazene chemistry have been synthesized and characterized as forward osmosis (FO) draw solutes. Commercially obtained hexachlorocyclotriphosphazene was reacted with the sodium salt of 4-ethylhydroxybenzoate to yield hexa(4-ethylcarboxylatophenoxy)phosphazene. Hydrolysis, followed by and neutralization with NaOH or LiOH, of the resulting acidic moieties yielded water soluble sodium and lithium phosphazene salts, respectively. Degrees of dissociation were determined through osmometry over the range of 0.05-0.5 m, giving degrees of 3.08-4.95 per mole, suggesting a high osmotic potential. The Li salt was found to be more ionized in solution than the sodium salt, and this was reflected in FO experiments where the Li salt gave higher initial fluxes (~ 7 L/m2h) as compared to the sodium salt (~6 L/m2h) at identical 0.07 m draw solution concentrations at 30 °C. Longer term experiments revealed no detectable degradation of the salts; however some hydrolysis of the cellulose acetate membrane was observed, presumably due to the pH of the phosphazene salt draw solution (pH = ~8).
Water Transport Polymers -- Structure/Property Relationships of a Series of Phosphazene Polymers
Christopher J. Orme; Eric S. Peterson; William F. Bauer; Frederick F. Stewart; Mason K. Harrup; Thomas A. Luther; John R. Klaehn; John E. Wey
2010-01-01
A study was undertaken to explore the water passing properties of a series of phosphazene polymers versus attached pendant group structure. Pendant groups containing different numbers ethyleneoxy groups were synthetically attached to the backbone of phosphazene polymers. Phosphazene polymers facilitate these types of studies because during their synthesis the polymer backbone is formed first and then the desired pendant groups are attached through nucleophilic substitution. For these studies, four polymer series were synthesized and tested for their water passing properties. The polymers contained different amounts of ethyleneoxy units. Two polymer families were synthesized and compared in this work. The critical difference in these two series is that one contained pendant groups with aromatic rings, in addition to the oligioethyleneoxy moieties, while the other does not. Polymers with phenyl group-containing pendant groups exhibited poor water permeability if they possessed fewer than six ethyleneoxy units. Polymers with more than six ethyleneoxy units inserted between the phenyl ring (tail) and the polymeric backbone, exhibited reasonable water permeability. Two additional series of mixed pendant group polymers were synthesized and the water passing properties of the phosphazenes varied in proportion to the hydrophilic to hydrophobic balance induced by each individual pendant group. A final study, polymers with shorter pendant groups, is shown to fully demonstrate the effect of pendant group on water permeability. These studies suggest that the polyphosphazenes may be tailored for specific water passing applications.
Phosphazene-catalyzed intramolecular cyclization of nitrogen-tethered alkynyl esters.
Kondoh, Azusa; Ando, Kenichi; Terada, Masahiro
2013-11-11
Intramolecular cyclization of nitrogen-tethered alkynyl esters catalyzed by phosphazene organosuperbases P2-tBu and P4-tBu was investigated. Both acyclic and cyclic substrates underwent 5-exo-dig and 5-endo-dig cyclization. This reaction is a rare example of the intramolecular addition of enolates of simple esters to alkynes. PMID:24064956
Using density functional theory to interpret the infrared spectra of flexible cyclic phosphazenes.
King, Adrian K; Plant, David F; Golding, Peter; Lawson, Michael A; Davies, Paul B
2012-03-01
The cyclic phosphazene trimer P(3)N(3)(OCH(2)CF(3))(6)and the related cyclic tetramer P(4)N(4)(OCH(2)CF(3))(8) have been synthesized, isolated and their vapor-phase absorption spectra recorded at moderate resolution using an FTIR spectrometer. The interpretation of these spectra is achieved primarily by comparison with the results of high-precision density functional calculations, which enable the principal absorption features to be assigned and conclusions to be drawn regarding the geometries and conformations adopted by both molecules. These in turn allow interesting comparisons to be made with analogous cyclic halo-phosphazenes (such as P(3)N(3)Cl(6)) and other related ring compounds. The highly flexible nature of the two cyclic phosphazenes precludes a complete theoretical study of their potential energy hypersurfaces and a novel alternative approach involving the analysis of a carefully selected subset of the possible molecular conformations has been shown to produce satisfactory results. The two cyclic phosphazene oligomers have been proposed as the major low-to-medium temperature pyrolysis products of the parent polyphosphazene (PN(OCH(2)CF(3))(2))(n), and the identification of vibrational absorption features characteristic of each molecule will enable future studies to test the validity of this proposition. PMID:22260404
Haddon, R.C.; Chichester-Hicks, S.V.; Mayo, S.L.
1988-06-01
The synthesis and properties of a new series of 1,9-diamino-substituted phenalene complexes of the cyclotriphosphazene ring system is described. One of the compounds is shown to be amphoteric, and this behavior allows an examination of the response of the phosphazene linkage to variations in exocyclic charge density at the spiro center in a plane perpendicular to the cyclotriphosphazene ring system. /sup 31/P NMR spectroscopy indicates that substituent lone pairs with this orientation are not effective in long-range delocalization within the phosphazene linkage (in accord with their theoretical model of spiro delocalization). An x-ray crystal structure of one compound (7) identifies the presence of clathrated molecules of chloroform together with doubly hydrogen-bonded pairs of the phenalene-phosphazene complexes in the lattice. Crystal data for 7 (C/sub 13/H/sub 8/Cl/sub 4/N/sub 5/P/sub 3/ /times/ CHCl/sub 3/): monoclinic space group P2/sub 1//c, a = 12.401 (4) /angstrom/, b = 28.404 (6) /angstrom/, c = 12.962 (3) /angstrom/, /beta/ = 91.76 (2)/degree/, V = 4564 (2) /angstrom//sup 3/, Z = 8, R = 0.050 for 4525 reflections. 24 references, 3 figures, 7 tables.
Poly(phosphazene) solid state polymeric electrolytes for Li energy storage devices
NASA Astrophysics Data System (ADS)
Palmer, David N.
ESCA and solvatochromic related modeling data suggest that poly-2-(2-methoxyethoxy/ethoxy/phosphazene) and related polymers may be good starting material candidates for room temperature solid-state Li salt complex electrolytes for thin film Li energy storage devices. Cyclic cell, complex impedance and ionic conductivity data indicate that the practical application of these or similar materials to primary and secondary Li devices is dependent on several factors including polymer syntheses methods; polymer substituent group moiety, Li anode reactive species after synthesis and purification, thin-film stability and resolution of current carrying limitations.
Synthesis of novel magnetic phosphazene-containing polymer microspheres with active hydroxyl groups
NASA Astrophysics Data System (ADS)
Zhang, Xiaoyan; Tang, Xiaozhen; Huang, Xiaobin
2009-09-01
Monodisperse magnetic phosphazene-containing polymer microspheres with active hydroxyl groups were prepared at room temperature by ultrasonic irradiation. The morphology and structure of the magnetic poly(cyclotriphosphazene- co-4,4'-sulfonyldiphenol) (PZS) microspheres were characterized and the coordination behavior between magnetic nanoparticles and PZS microspheres was investigated. The magnetic measurements reveal that the magnetic microspheres are superparamagnetic with saturation magnetization of 34.9 emu/g. The paper presents a simple, economic and environmentally friendly route to preparing monodisperse magnetic hybrid inorganic-organic microspheres with functional groups.
NASA Astrophysics Data System (ADS)
Galasso, V.
1984-01-01
The unusual PE and NMR spectroscopic properties of cis and trans diazene, phosphazene, diphosphene, and diarsene have been studied at non-empirical level. In particular, the ionization energies of the outer valence orbitals have been calculated by the many-body formalism according to Cederbaum, and the nuclear screening constants and the nuclear spin-spin coupling constants by the SOS CI perturbation technique according to Nakatsuji's approach, taking into account all the spin interaction operators. The calculated values correlate satisfactorily with the available experimental data and account for the peculiar magnitude of these observables in the class of the two-coordinate ?X?Y? compounds.
Synthesis and Characterization of Cyclic and Linear Phosphazenes with Phosphorus-Sulfur Linkages
Luther, Thomas Alan; Harrup, Mason Kurt; Stewart, Frederick Forrest
2004-04-01
Recent research at the INEEL has focused on the versatility inherent in polyphosphazene chemistry to membrane separations involving water transport through polymer materials.1 Polyphosphazenes, a hybrid organic and inorganic polymer, have been shown to be effective membranes in gas separation2 and liquid pervaporation applications.3 These characteristics are due to the inorganic nature of the backbone that provides these materials with remarkable chemical and mechanical stability. Additionally, phosphazene materials can be tailored to specific applications depending on the type of pendant groups that are attached to the phosphorus atoms of the backbone.
The use of phosphazene additives to enhance the performance of PFPAE lubricants
NASA Astrophysics Data System (ADS)
Perettie, D. J.; Morgan, T. A.; Zhao, Q.; Kang, H.-J.; Talke, F. E.
1999-03-01
Cyclic phosphazenes are being developed as advanced lubricant additives for both rigid and flexible thin film magnetic media. Contact Start-Stop (CSS) test results with X-1P as an additive with perfluorinated polyalkylethers (PFPAEs) show it to have similar tribological performance to standard perfluoropolyalkyl ethers (PFPAE) as a topical lubricant on carbon-overcoated thin film rigid disks under ambient conditions. However, X-1P as an additive with PFPAE's significantly outperforms Z-DOL and AM3001in CSS testing under hot/wet (30°C, 80 RH) conditions. In addition to its CSS test performance, X-1P as an additive was found to stabilize the PFPAE when heated in the presence of water and standard slider material, Al 2O 3-TiC.
Phosphazene Based Additives for Improvement of Safety and Battery Lifetimes in Lithium-Ion Batteries
Mason K Harrup; Kevin L Gering; Harry W Rollins; Sergiy V Sazhin; Michael T Benson; David K Jamison; Christopher J Michelbacher
2011-10-01
There need to be significant improvements made in lithium-ion battery technology, principally in the areas of safety and useful lifetimes to truly enable widespread adoption of large format batteries for the electrification of the light transportation fleet. In order to effect the transition to lithium ion technology in a timely fashion, one promising next step is through improvements to the electrolyte in the form of novel additives that simultaneously improve safety and useful lifetimes without impairing performance characteristics over wide temperature and cycle duty ranges. Recent efforts in our laboratory have been focused on the development of such additives with all the requisite properties enumerated above. We present the results of the study of novel phosphazene based electrolytes additives.
Harry W. Rollins; Mason K. Harrup; Eric J. Dufek; David K. Jamison; Sergiy V. Sazhin; Kevin L. Gering; Dayna L. Daubaras
2014-10-01
The safety of lithium-ion batteries is coming under increased scrutiny as they are being adopted for large format applications especially in the vehicle transportation industry and for grid-scale energy storage. The primary short-comings of lithium-ion batteries are the flammability of the liquid electrolyte and sensitivity to high voltage and elevated temperatures. We have synthesized a series of non-flammable fluorinated phosphazene liquids and blended them with conventional carbonate solvents. While the use of these phosphazenes as standalone electrolytes is highly desirable, they simply do not satisfy all of the many requirements that must be met such as high LiPF6 solubility and low viscosity, thus we have used them as additives and co-solvents in blends with typical carbonates. The physical and electrochemical properties of the electrolyte blends were characterized, and then the blends were used to build 2032-type coin cells which were evaluated at constant current cycling rates from C/10 to C/1. We have evaluated the performance of the electrolytes by determining the conductivity, viscosity, flash point, vapor pressure, thermal stability, electrochemical window, cell cycling data, and the ability to form solid electrolyte interphase (SEI) films. This paper presents our results on a series of chemically similar fluorinated cyclic phosphazene trimers, the FM series, which has exhibited numerous beneficial effects on battery performance, lifetimes, and safety aspects.
Wang, Shu-Gen; Jiang, Xin; Chen, Peng-Cheng; Yu, An-Guo; Huang, Xiao-Jun
2012-01-01
A core/sheath nanofiber membrane with poly[bis(p-methylphenoxy)]phosphazene (PMPPh) as the sheath and easily spinnable polyacrylonitrile (PAN) as the core was prepared via a coaxial electrospinning process. Field-emission scanning electron microscopy and transmission electron microscopy were used to characterize the morphology of the nanofiber membrane. It was found that the concentration of the PAN spinning solution and the ratio of the core/sheath solution flow rates played a decisive role in the coaxial electrospinning process. In addition, the stabilized core/sheath PMPPh nanofiber membrane was investigated as a support for enzyme immobilization because of its excellent biocompatibility, high surface/volume ratio, and large porosity. Lipase from Candida rugosa was immobilized on the nanofiber membrane by adsorption. The properties of the immobilized lipase on the polyphosphazene nanofiber membrane were studied and compared with those of a PAN nanofiber membrane. The results showed that the adsorption capacity (20.4 ± 2.7 mg/g) and activity retention (63.7%) of the immobilized lipase on the polyphosphazene nanofiber membrane were higher than those on the PAN membrane. PMID:23203055
NSDL National Science Digital Library
Bourne, Murray
Murray Bourne developed the Interactive Mathematics site while working as a mathematics lecturer at Ngee Ann Polytechnic in Singapore. The site contains numerous mathematics tutorials and resources for students and teachers alike. This specific page is focused on differentiation, or finding derivatives. Bourne walks users through an introduction to differentiation and limits, and then moves on to more specific applications like rate of change, derivatives of polynomials, and differentiating powers of a function. Each topic includes graphs and interactive materials designed to aid users in understanding the presented concepts. The information here is presented in a clear, straightforward manner that is appropriate for introductory and advanced calculus students alike.
NSDL National Science Digital Library
2010-01-01
In this activity, students input functions in order to calculate the derivative and tangent line of that function. This activity allows students to explore tangent lines of various functions. This activity includes supplemental materials, including background information about the topics covered, a description of how to use the application, and exploration questions for use with the java applet.
An e.s.c.a. study of atomic oxygen interactions with phosphazene-coated polyimide films
NASA Technical Reports Server (NTRS)
Fewell, Larry L.; Finney, Lorie
1991-01-01
Metallic as well as most nonmetallic materials experience oxidation and mass loss via surface erosion in low earth orbit as shown in previous Space Shuttle flights. This study is an evaluation of select polyphosphazene polymers and their resistance to atomic oxygen attack. Electron spectroscopy for chemical analysis examinations of the surfaces of polyphosphazene coatings were monitored for microstructural changes induced during exposures to atomic oxygen. Sample exposures in oxygen plasmas and O(3P) beam were compared as to their effect on surface compositional changes in the polyphosphazene coating. High resolution line scans revealed rearrangements in the polymer backbone and scissioning reactions involving fluorocarbon units of long chain fluoroalkoxy pendant groups. Atom percents and peak areas of all species provided a detailed profile of the microstructural changes induced in phosphazene polymers as a result of exposures to atomic oxygen.
Sun, Jian; Wang, Xiaodong; Wu, Dezhen
2012-08-01
A novel halogen-free fire resistant epoxy resin with pendent spiro-cyclotriphosphazene groups was designed and synthesized via a three-step synthetic pathway. The chemical structures and compositions of spiro-cyclotriphosphazene precursors and final product were confirmed by (1)H, (13)C, and (31)P NMR spectroscopy, mass spectroscopy, elemental analysis, and Fourier transform infrared spectroscopy. The thermal curing behaviors of the synthesized epoxy resin with 4,4'-diamino-diphenylmethane, 4,4'-diamino-diphenyl sulfone, and novolac as hardeners were investigated by differential scanning calorimetry (DSC), and the curing kinetics were also studied under a nonisothermal condition. The evaluation of the thermal properties demonstrated that these thermosets achieved a good thermal resistance due to their high glass transition temperatures more than 150 °C, and also gained high thermal stabilities with high char yields. The flammability characteristics of the spirocyclic phosphazene-based epoxy thermosets cured with these three hardeners were investigated on the basis of the results obtained from the limiting oxygen index (LOI) and UL-94 vertical burning experiments as well as the analysis of the residual chars collected from the vertical burning tests. The high LOI values and UL-94 V-0 classification of these epoxy thermosets indicated that the incorporation of phosphazene rings into the backbone chain imparts nonflammability to the epoxy resin owing to the unique combination of phosphorus and nitrogen following by a synergistic effect on flame retardancy. The epoxy resin obtained in this study is a green functional polymer and will become a potential candidate for fire- and heat-resistant applications in electronic and microelectronic fields with more safety and excellent performance. PMID:22833687
Meng Deng; Lakshmi S. Nair; Syam P. Nukavarapu; Sangamesh G. Kumbar; Tao Jiang; Nicholas R. Krogman; Anurima Singh; Harry R. Allcock; Cato T. Laurencin
2008-01-01
Previously we demonstrated the ability of ethyl glycinato substituted polyphosphazenes to neutralize the acidic degradation products and control the degradation rate of poly(lactic acid-glycolic acid) (PLAGA) by blending. In this study, blends of high strength poly[(50% ethyl alanato) (50% p-phenyl phenoxy) phosphazene] (PNEA50PhPh50) and 85:15 PLAGA were prepared using a mutual solvent approach. Three different solvents, methylene chloride (MC), chloroform
NASA Astrophysics Data System (ADS)
K?l?ç, A.; Begeç, S.; K?l?ç, Z.; Hökelek, T.
2000-01-01
The reactions of Cl 3P?N-P(0)Cl 2 (1) with Sodium 2,4,6- tert-butylphenoxide and sodium 2,6-di- tert-butyl-4-methylphenoxide give geminal bis products (2) and (3), respectively. Compounds (2) and (3) have been characterised by elemental analysis, IR, 1H-, 13C- and 31P-NMR and the structure of compound (2) has been examined crystallographically. It crystallizes in the monoclinic space group P2 1/n with a=10.056(1), b=25.986(1), c=15.533(1)Å, ?=95.9(1)°, V=4037.6(1)Å 3, Z=4 and D x=1.19 g cm -3. The bulky substituents are instrumental in determining the molecular geometry. The P-N bonds have neither single-nor double-bond character and are substantially shorter than the ideal P-N single bond. The P?O double bond is abnormally long and it has a single bond character. The P-N-P angle [158.0(3)°] is the largest one for the reported acyclic phosphazene derivatives in the literature.
Rebane, Riin; Oldekop, Maarja-Liisa; Herodes, Koit
2012-09-01
Amino acid analysis with high performance liquid chromatography with electrospray ionization mass spectrometry (LC-ESI-MS) is an emerging method. For more sensitive analysis, derivatization is used and next to commercially available derivatization reagents such as dansyl chloride (DNS), 9-fluorenylmethyl chloroformate (FMOC-Cl) and diethyl ethoxymethylenemalonate (DEEMM), new derivatization reagents are designed specially for LC-ESI-MS, like p-N,N,N-trimethylammonioanilyl N'-hydroxysuccinimidyl carbamate iodide (TAHS) which provides very low limits of detection. In this work, a novel phosphazene based derivatization reagent (FOSF) that provides comparable limits of quantitation (LoQ) to TAHS is introduced. Moreover, a thorough comparison between FOSF, TAHS, DNS, FMOC-Cl and DEEMM is carried out for 7 different amino acids - Arg, Asp, Gly, ?-Ala, Pro, Trp and Phe. This is a first time that thorough comparison is carried out on the same instrument for amino acid derivatization reagents. Results on the same instrument for five amino acid derivatization reagents show that novel reagents are sensitive with LoQ values around 80 fmol but have disadvantages such as problematic chromatographic separation. Next to novel reagents, DEEMM offers very good LoQ-s (average of 150 fmol) and wide dynamic linear range. PMID:22889992
Yang, Yongxin; Zhang, Zhiwen; Chen, Lingli; Gu, Wangwen; Li, Yaping
2010-04-12
To achieve efficient gene delivery to the tumor after intravenous administration, biodegradable poly(2-(2-aminoethyoxy)ethoxy)phosphazene (PAEP) was modified by lactobionic acid, bearing a galactose group as a targeting ligand. Galactosylated poly(2-(2-aminoethyoxy)ethoxy)phosphazene (Gal-PAEP) with 4.9% substitution degree of galactose could condense pDNA into nanoparticles with a size around 130 nm at the polymer/DNA ratio (N/P) of 2-40. For BEL-7402 cells, the in vitro transfection efficiency of gal-PAEP/DNA complex nanoparticles (gal-PACNs) was much higher than that of the PAEP/DNA complex nanoparticles (PACNs). MTT assay indicated that the cytotoxicity of PACNs significantly decreased after conjugating with the galactose moiety. Gal-PACNs displayed the selective gene expression in the tumor and liver with relatively low gene expression in the lung or other organs compared with PACNs. These results suggested that gal-PACNs could be a promising targeting gene carrier to deliver a therapeutic gene in future. PMID:20302354
NASA Astrophysics Data System (ADS)
Young, Scott G.; Magill, Joseph H.
1989-05-01
In situ solid state variable temperature NMR measurements have been made on Poly(bis(trifluoroethoxy)phosphazene above and below the first order thermotropic transition, T(1). A single mobile ordered 2D phase exists above T(1). Below T(1) and at room temperature there is a 3D phase in agreement with other physical property measurements. The OCH2CF3 side chains exhibit similar mobility on either side of the 2D in equilibrium with 3D transition. The activation energies associated with the CH2 and CF3 side groups are E sub CH2 about 17.3 kJ/mole and E sub CF3 about 13.7 kJ/mole. The spin lattice relaxation measurements for these same groups are 1.75s. and 3.55s. respectively. The crystallinity ascertained from solid state NMR results is strongly dependent upon annealing conditions and temperature of measurement.
Kevin L. Gering; Mason K. Harrup; Eric J. Dufek; Sergiy V. Sazhin; Harry W. Rollins; David K. Jamison; Fred F. Stewart; John Burba
2013-09-01
Electrolytes play a central role in performance and aging in most electrochemical systems. As automotive and grid applications place a higher reliance on electrochemical stored energy, it becomes more urgent to have electrolyte components that enable optimal battery performance while promoting battery safety and longevity. Safety remains a foremost concern for widespread utilization of Li-ion technology in electric-drive vehicles, especially as the focus turns to higher voltage systems (5V). This work capitalizes on the long established INL expertise regarding phosphazene chemistry, aimed at battery-viable compounds for electrolytes and electrodes that are highly tolerant to abusive conditions. This report showcases our 2013 work for the DOE applied battery research (ABR) program, wherein testing results are summarized for INL electrolytes and alternative anode materials.
Phosphazene Polymers Containing Carborane
NASA Technical Reports Server (NTRS)
Fewell, L. L.; Parker, J. A.; Basi, R. J.
1986-01-01
Addition of carborane increases thermal stability. Carborane-substituted polyphosphazenes prepared by thermal polymerization of phenylcarbonyl-pentachlorocyclotriphosphazene followed by reaction with sodium trifluoroethoxide to replace remaining chlorine atoms with trifluoroethoxy groups. Improved polymers offer high char yields and resistance to hydrolysis.
Duan, Shun; Yang, Xiaoping; Mao, Jifu; Qi, Bing; Cai, Qing; Shen, Hong; Yang, Fei; Deng, Xuliang; Wang, Shenguo
2013-02-01
Biodegradable amino acid ester-substituted polyphosphazenes are unique biomaterials for tissue engineering. Considering the surface properties as topography and chemical composition having vital roles in regulating cellular response, in this study, a kind of micropatterned polyphosphazene films were prepared and subjected to osteoblasts culture. Briefly, poly(glycine ethyl ester-co-alanine ethyl ester)phosphazene (PGAP) was synthesized, and its solution in chloroform was cast under high (80%) or low (20%) environmental humidity. Honeycomb-patterned or flat PGAP films were resulted. By analyzing with scanning electron microscope, atomic force microscope, X-ray photoelectron spectroscope, and water contact angle measurement, the honeycomb-patterned PGAP films demonstrated higher surface roughness, phosphorous and nitrogen content, and hydrophilicity than the flat one. Although the initial cell attachment and proliferation on PGAP films were inferior to those on conventional poly(lactic-co-glycolic acid) films, P-containing PGAP was a sort of bone-binding bioactive polymer. With these alternations, honeycomb-patterned PGAP films had accordingly enhanced protein adsorption and apatite deposition in simulated body fluid and showed great advantages in promoting osteogenous differentiation. The results suggested a potential way to make polyphosphazenes as good choices for bone tissue regeneration by increasing their surface roughness and phosphorous content. PMID:22733644
NASA Astrophysics Data System (ADS)
Wis?ocka, ?aneta; Nowak, Iwona; Jarczewski, Arnold
2006-05-01
The rates of proton transfer reactions between C-acids of the series of nitroalkanes with increasing bulk of R=H, Me, Et, i-Pr substituents as 4-nitro-phenylnitromethane ( 1), 1-(4-nitrophenyl)-1-nitroethane ( 2), 1-(4-nitrophenyl)-1-nitropropane ( 3), 2-methyl-1-(4-nitrophenyl)-1-nitropropane ( 4) and the P 1- t-Bu phosphazene have been measured in THF at pseudo-first-order conditions. The product of the proton transfer reaction with P 1- t-Bu is associated into ion pair. The equilibrium constants decrease along with growing bulk of alkyl substituent in the reacting C-acid: >100 000, 1170, 590, and 11.8 for 1, 2, 3, 4, respectively. The second order rate constants ( k2H) for this very strong base and C-acids are rapidly declining: 9357, 2.31, 0.66, 0.09 dm 3 mol -1 s -1 for 1, 2, 3, 4, respectively, and could not be accounted for the small values of the enthalpies of activation ?HH?=6.1,18.0,20.7 and 11.1 kJ mol. The appropriate values of the entropies of activation were all negative and relatively large ?SH?=-149.7,-176.5,-178.7,-227.8 J mol deg indicating an importance of steric and ordering effects in forming the transition state. The primary deuterium kinetic isotope effects are large showing tendency of reverse relation towards steric hindrance of the reacting C-acids, kH/ kD=15.8, 13.6, 13.2 for 1, 2, and 3, respectively. The explanation of the unusual slow proton transfer abstraction caused by this extremely strong base is undertaken.
Kondoh, Azusa; Aoki, Takuma; Terada, Masahiro
2014-07-01
A novel catalytic cyclization reaction of alkynyl ?-ketoanilide was developed by utilizing the [1,2]-phospha-Brook rearrangement. This reaction involves the generation of an amide enolate via the umpolung process, that is the addition of dialkyl phosphite to a keto moiety followed by the [1,2]-phospha-Brook rearrangement, and the subsequent intramolecular addition of the enolate to an alkyne to afford 3,4-dihydro-2-quinolone derivatives. Under high-temperature reaction conditions, further rearrangement of the allylic phosphate moiety occurs to provide 2-quinolone derivatives. PMID:24955761
Garlapati, Srinivas; Eng, Nelson F; Wilson, Heather L; Buchanan, Rachelle; Mutwiri, George K; Babiuk, Lorne A; Gerdts, Volker
2010-12-01
We generated poly[di(carboxylatophenoxy)-phosphazene] (PCPP) microparticles encapsulating ovalbumin (OVA) and CpG of 0.5-2.5 ?m in diameter with an encapsulation efficiency of approximately 63% and 95% respectively. In mice the microparticles generated high antigen-specific IgG, IgG1 and IgG2a titers with higher IgG2a/IgG1 ratios. Whole body in vivo imaging of mice subcutaneously injected with MPs showed several fold increase of OVA and CpG in draining inguinal lymph nodes compared to soluble formulations. We conclude that PCPP MPs are more effective in enhancing immune responses compared to soluble formulations, due to co-delivery of OVA and CpG resulting in a Th1 type of immune response. PMID:21036133
Kumar, M. Jagadesh
and hexachlorocyclotriphosphazenes were carried out at -78 °C with the formation of monoethynylferrocene and geminal of these ethynylferrocene substituted phosphazenes with CpCo(COD) and benzyl azide. The ethynylferrocene substituted phosphazene towards organic azide, mono(ethynylferrocenyl) cyclofluorophosphazene was refluxed with benzyl
NASA Astrophysics Data System (ADS)
Nguyen, Minh Tho; Ha, Tae-Kyu
1989-06-01
The 1,2 hydrogen shift was studied in three model systems, H 2CS, H 2PN and H 2P 2, using ab initio MO methods. Geometries were determined at the MP2/6-31G** level with relative energies estimated by single-point calculations at the MP4/ 6-311++G (df, p) level, including zero-point corrections. For H 2CS the reason for previous conflicting reports is explained; it is confirmed that the 1,2 shift takes place in the molecular plane. In H 2PN, out-of-plane transfer is marginally favoured over in-plane, suggesting that the latter becomes effective in substituted phosphazenes. In contrast, out-of-plane transfer predominates in H 2P 2. These results suggest that the migrating hydrogen behaves as a hydride at the transition states in H 2CS and H 2PN but as a proton in H 2P 2. Stabilizing interactions between the migrating proton and the ? electron of the double bond favours an out-of-plane migration in the latter case. Relative energies are estimated as follows (in kcal/mol): H 2C?S (0.0)?TS (78.6)?trans-HC?SH (47.6); HN?PH (0.0)?TS (81.8)?N?PH 2 (39.0) and HP?PH (0.0)?TS (51.4)?P?PH 2 (25.8).
NSDL National Science Digital Library
Derivatives are financial securities whose value is derived from another "underlying" financial security. Options, futures, swaps, swaptions, and structured notes are all examples of derivative securities. Derivatives can be used in hedging, protecting against financial risk, or can be used to speculate on the movement of commodity or security prices, interest rates, or the levels of financial indices. The valuation of derivatives makes use of the statistical mathematics of uncertainty. With links to related articles. See also Derivatives Concepts A-Z, glossary of derivatives-related terminology designed to make the other articles in the Financial Pipeline's Derivatives section easier to understand.
Shibata, Norio; Nishimine, Takayuki; Shibata, Naoyuki; Tokunaga, Etsuko; Kawada, Kosuke; Kagawa, Takumi; Aceña, José Luis; Sorochinsky, Alexander E; Soloshonok, Vadim A
2014-03-01
Inorganic as well as organic base catalysis was found to be effective for diastereoselective Mannich additions of malonic acid derivatives to (SS)-N-(tert-butanesulfinyl)-3,3,3-trifluoroacetaldimine. In the presence of catalytic amounts of inorganic bases, n-BuLi or DMAP, the reaction gives the corresponding (R,SS)-?-aminomalonates in good yield and with diastereoselectivity up to 9/1 dr. In contrast, phosphazene bases favour the formation of the (S,SS)-diastereomer with selectivities as high as 99/1. Simple choosing of an appropriate base catalyst for the Mannich addition reaction allowed us to obtain enantiomerically pure (R)- or (S)-configured 3-amino-4,4,4-trifluorobutanoic acids after hydrolysis and decarboxylation of the corresponding ?-aminomalonates. PMID:24445698
Noller, Johannes, E-mail: johannes.noller08@imperial.ac.uk [Theoretical Physics, Blackett Laboratory, Imperial College London, Prince Consort Road, London, SW7 2BZ (United Kingdom)
2012-07-01
We consider generalized chameleon models where the conformal coupling between matter and gravitational geometries is not only a function of the chameleon field ?, but also of its derivatives via higher order co-ordinate invariants (such as ?{sub ?}??{sup ?}?,??,...). Specifically we consider the first such non-trivial conformal factor A(?,?{sub ?}??{sup ?}?). The associated phenomenology is investigated and we show that such theories have a new generic mass-altering mechanism, potentially assisting the generation of a sufficiently large chameleon mass in dense environments. The most general effective potential is derived for such derivative chameleon setups and explicit examples are given. Interestingly this points us to the existence of a purely derivative chameleon protected by a shift symmetry for ? ? ?+c. We also discuss potential ghost-like instabilities associated with mass-lifting mechanisms and find another, mass-lowering and instability-free, branch of solutions. This suggests that, barring fine-tuning, stable derivative models are in fact typically anti-chameleons that suppress the field's mass in dense environments. Furthermore we investigate modifications to the thin-shell regime and prove a no-go theorem for chameleon effects in non-conformal geometries of the disformal type.
Oxime-phosphazenes containing dioxybiphenyl groups
Erol Çil; Mustafa Arslan
2009-01-01
2,2-Dichloro-4,4,6,6-bis[spiro(2?,2??-dioxy-1?,1??-biphenylyl]cyclotriphosphazene (2) was obtained from the reaction of hexachlorocyclotriphosphazene (1) with biphenyl-2,2?-diol. 2,2-Bis(4-formylphenoxy)-4,4,6,6-bis[spiro(2?,2??-dioxy-1?,1??-biphenylyl]cyclotriphosphazene (3) was synthesized from the reaction of 2 with 4-hydroxybenzaldehyde. The novel oxime-cyclophosphazene containing dioxybiphenyl groups (4) was synthesized from the reaction of 3 with hydroxylaminehydrochloride in pyridine. The reactions of this oxime-cyclophosphazene with propanoyl chloride, allyl bromide, acetyl chloride, methyl iodide, benzoyl chloride, 4-methoxybenzoyl chloride, benzenesulfonyl
Kögel, Julius F; Abac?lar, Nuri C; Weber, Felicia; Oelkers, Benjamin; Harms, Klaus; Kova?evi?, Borislav; Sundermeyer, Jörg
2014-05-12
Investigations on the Staudinger reaction between 1,8-diazidonaphthalene and phosphorous(III) building blocks, a key step in the synthesis of superbasic bisphosphazene proton sponges, yielded a set of bisphosphazides with a constrained geometry 1,8-disubstituted naphthalene backbone. This compound class has attracted our interest not only due to their surprisingly high stability, but in particular because of their theoretically predicted basicity in the range of their bisphosphazene analogues that can be referred to the constrained geometry interaction of two highly basic nitrogen atoms. Eleven new bisphosphazides bearing simple P-amino groups as well as P-guanidino substituents, azaphosphatrane moieties, P2 building blocks, or chiral P-amino substituents derived from L-proline are presented. They were studied concerning their spectroscopic properties and partly also their chromophoric and structural features. In the case of the pyrrolidino-substituted TPPN(2N2) (TPPN = 1,8-bis(trispyrrolidinophosphazenyl)naphthalene), the stepwise nitrogen elimination is investigated theoretically and experimentally, which led to the isolation and structural characterization of TPPN(1N2) bearing a phosphazide and a phosphazene functionality in one molecule. Attempts to protonate the obtained bisphosphazides and to prove the computationally predicted pKBH(+) values through NMR titration reactions resulted in their decay, which again was rationalized by theoretical calculations. Altogether we present the so far most extensive spectroscopic, structural and theoretical investigation of constrained geometry bisphosphazides and their Brønsted and Lewis basic properties. PMID:24687589
Fractional Derivative as Fractional Power of Derivative
Vasily E. Tarasov
2007-11-16
Definitions of fractional derivatives as fractional powers of derivative operators are suggested. The Taylor series and Fourier series are used to define fractional power of self-adjoint derivative operator. The Fourier integrals and Weyl quantization procedure are applied to derive the definition of fractional derivative operator. Fractional generalization of concept of stability is considered.
NASA Astrophysics Data System (ADS)
Astorg, Jean-Marc
1993-01-01
The Ariane 5 light derivatives are studied in order to complete Ariane 5 launch services with regard to medium size Sun synchronous spacecrafts (S derivative) and small satellites (P derivative). The P derivative is a three stage launcher with two solid propellant motors and a bipropellant upper stage. It is capable of placing 1 ton in a 1000 km circular polar orbit or two 450 kg payloads in the same orbit. The light derivatives are mainly derived from the Ariane 5 solid propellant booster and upper stage. The payload volume is particulary large (2.8 m internal maximal diameter, 6 m height). The light derivatives will be launched from the Ariane spaceport in Guyana. They will use Ariane 5 facilities for payload preparation and launch operation with a specific building for launcher integration. The first flight of the P derivative is scheduled for 1998.
Thermodynamic Derivatives without Tables
John S. Thomsen
1964-01-01
A simple, concise method is presented for deriving any desired thermodynamic first derivative in terms of a minimal basic set. The method is given in detail for a two-degree-of-freedom system, specifically a homogeneous fluid. The variables involved, including thermodynamic potentials, are briefly reviewed and the Maxwell relations derived. Differentials of all variables are expressed in terms of those of p
Biologically Active Cellulose Derivatives
A D Virnik
1973-01-01
The review deals with the synthesis and applications of biologically active cellulose derivatives. The synthesis of cellulose derivatives with antimicrobial and haemostatic (arresting blood flow) properties, the possible fields of application of antimicrobial and haemostatic cellulose materials, the synthesis of graft copolymers of cellulose and biologically active proteins (enzymes and antigens), and medical applications of cellulose derivatives containing ionogenic or
Partial Derivatives: Geometric Visualization
NSDL National Science Digital Library
James Rutledge
This write-pair-share activity presents Calculus III students with a worksheet containing several exercises that require them to find partial derivatives of functions of two variables. Afterwards, a series of Web-based animations are used to illustrate the surface of each function, the path of the indicated partial derivative for a specified value of the variable and the value of the derivative at each point along the path.
Endohedral Metallofullerene Derivatives
NASA Technical Reports Server (NTRS)
Dorn, Harry C. (Inventor); Iezzi, Erick B. (Inventor); Duchamp, James (Inventor)
2008-01-01
Trimetallic nitride endohedral metallofullerene derivatives and their preparation are described. The trimetallic nitride endohedral metallofullerene derivatives have the general formula A(sub 3-n)X(sub n)@C(sub m)(R) where n ranges from 0 to 3, A and X may be trivalent metals and may be either rare earth metal or group IIIB metals, m is between about 60 and about 200, and R is preferably an organic group. Derivatives where the R group forms cyclized derivatives with the fullerene cage are also described.
Jun Liu; Jun Pan
2002-01-01
This paper studies the optimal investment strategy of an investor who can access not only the bond and the stock markets, but also the derivatives market. We consider the investment situation where, in addition to the usual diusive price shocks, the stock market experiences sudden price jumps and stochastic volatility. The dynamic portfolio problem involving derivatives is solved in closed-form.
Partial Derivative Visualization Gallery
NSDL National Science Digital Library
Roberts, Lila F.
2004-11-11
This resource is a small gallery of demos for illustrating partial derivatives geometrically. These animations can be used by instructors in a classroom setting or by students to aid in acquiring a visualization background for partial derivatives. Two file formats, gif and QuickTime files are used for the animations which can be downloaded.
NASA Astrophysics Data System (ADS)
Veith, Michael; Kross, Maria; Labarre, Jean-François
1991-03-01
Syntheses and molecular structures of three metallated (Li, Zn, Mg) derivatives of the macrocycle-bearing cyclophosphazene N 3P 3Cl 4 [HN?(CH 2) 3?O?(CH 2) 2?O?(CH 2) 3?NH] (coded as SPIRO 30203, 1) are reported. These three molecular structures reveal three different patterns of metal coordination. In compound 2 one of the two hydrogen atoms in SPIRO 3O2O3 is substituted by lithium generating a dimeric structure with pentacoordinated lithium centers. This structure is further stabilized by N?H hydrogen bonds. In 3 both hydrogen atoms of the macrocyclic loop are replaced by two zinc atoms through a cross-link metallation leading again to a dimeric molecule. In this compound the Zn atom is found to be in a trigonal bipyramidal environment with one very long N?Zn interaction. The origin of the dimerization of the magnesium compound 4 is analogous to 3. Magnesium is in the center of a distorted octahedron, coordinated with the O- and N-donors of the macrocyclic loop and also one nitrogen atom of the N 3P 3 ring. 4 is the first example of a metallic center coordinated by a neutral phosphazene ligand. Typical metal-N and metal-O distances are (in Å): Li-O, 2.05-2.07; Li-N, 2.07-2.36; Zn-O, 2.08-2.14; Zn?N, 1.94-1.95 (2.49); Mg?O, 2.09-2.14; Mg?N, 2.07-2.31.
Oxygenated Derivatives of Hydrocarbons
Technology Transfer Automated Retrieval System (TEKTRAN)
For the book entitled “Insect Hydrocarbons: Biology, Biochemistry and Chemical Ecology”, this chapter presents a comprehensive review of the occurrence, structure and function of oxygenated derivatives of hydrocarbons. The book chapter focuses on the occurrence, structural identification and functi...
Liu, Jun
2003-09-25
This paper studies the optimal investment strategy of an investor who can access not only the bond and the stock markets, but also the derivatives market. We consider the investment situation where, in addition to the usual ...
Deriving Common Model Characteristics
NSDL National Science Digital Library
Jennifer Momsen
In this activity, students confront several different models - from the DNA helix Watson and Crick constructed in their laboratory to a map of McDonalds density in the US - and work in small groups to derive their commonalities.
Rüther, Henrique
2007-01-01
The amounts outstanding of credit derivatives have grown exponentially over the past years, and these financial intruments that allow market participants to trade credit risk have become very popular in Europe and in the ...
Teaching Cournot without Derivatives.
ERIC Educational Resources Information Center
Dufwenberg, Martin
2001-01-01
Presents a simple technique for teaching the Cournot model to first-year microeconomic students. Involves demonstrating, without the use of derivatives, that out of all rectangles with a common perimeter, the square has the greatest area. (RLH)
NSDL National Science Digital Library
Once again, the Mathematical Association of America has struck instructional gold with this latest gem from their online collection of resources for mathematics educators. Created by Barbara Margolius, this derivative matching game presents users with a game board showing graphs of functions on cards. Essentially, the goal of the game is to match the functions with their derivatives. Visitors can begin by reading an overview of the game, along with some brief instructions, and then they should dive right in. The game can also be customized to match functions with just first derivatives or both first and second derivatives. Mathematics educators will have a lot of fun with this one, and even the mathematically uncertain can be drawn into the fold with this easy to use resource.
Lin, Shaowei
2014-07-02
The enactment of derivative action was expected to be actively used by shareholders to protect their interests. In fact, it turned out that this reform effort seemed futile as the right to engage in such actions was ...
Extended Derivative Dispersion Relations
R. F. Avila; M. J. Menon
2006-01-24
It is shown that, for a wide class of functions with physical interest as forward scattering amplitudes, integral dispersion relations can be replaced by derivative forms without any high-energy approximation. The applicability of these extended derivative relations, in the investigation of forward proton-proton and antiproton-proton elastic scattering, is exemplified by means of a Pomeron-Reggeon model with totally nondegenerate trajectories.
Derivative beliefs and evaluations
Daniel A. Sheinin; Laurette Dubé; Bernd H. Schmitt
2008-01-01
Purpose – The purpose of this research is to examine how consumers form beliefs and evaluate derivatives (e.g. handheld computers) and branded derivatives (e.g. Palm handheld computers). The aim is to study how consumers combine two categories (e.g. “handheld products” and “computers”) to form beliefs, how the similarity between the categories influences beliefs, how the addition of a brand changes
Semisynthetic Derivatives of Epothilones
NASA Astrophysics Data System (ADS)
Altmann, Karl-Heinz
Semisynthetic derivatives of natural products traditionally occupy a prominent space in natural-product-based drug discovery (1, 2). As many biologically active natural products exhibit a high degree of structural complexity (3), the chemical derivatization of material isolated from natural sources often represents the only feasible means (or at least the only economically viable approach) to explore structure-activity-relationships (SAR) and to produce analogs with more favorable pharmacokinetic and pharmacological properties than the natural product lead. Examples of clinically important drugs that are semisynthetic derivatives of natural products exist in virtually all disease areas (1, 2); in the treatment of cancer this includes compounds such as etoposide or teniposide (derived from podophyllotoxin) (4-6), irinotecan and topotecan (derived from camptothecin) (7-9), or docetaxel (derived from 10-deacetylbaccatin III) (10, 11). Even for taxol (11), which is a natural product (12), the sustained supply of sufficient quantities of material for widespread clinical use could only be secured through the development of a semisynthetic production process from another natural product, namely, 10-deacetylbaccatin III (13). In light of these facts, it is not surprising that semisynthesis approaches have also featured prominently in the elucidation of the SAR for epothilones and in the discovery of a number of clinical development candidates.
NASA Astrophysics Data System (ADS)
Bilge, Selen; Özgüç, Bilgehan; Safran, Serap; Demiriz, ?emsay; ??ler, Hikmet; Hayval?, Mustafa; K?l?ç, Zeynel; Hökelek, Tuncer
2005-06-01
The condensation reaction of partly substituted spiro-cyclophosphazenic lariat (PNP-pivot) ethers, N 3P 3[( o-NHPhO) 2R]Cl 4 ( 5- 8), where R=-CH 2CH 2-, -CH 2CH 2CH 2-, -CH 2CH 2OCH 2CH 2-, and -CH 2PhCH 2-, with pyrrolidine have been afforded fully substituted pyrrolidino phosphazene derivatives ( 9- 12) (Scheme). There are the first examples of the spiro-cyclophosphazenic lariat (PNP-pivot) ether ligands with N 2O x-( x=2, 3) donor type containing 11-14 membered macrocycles. The solid state structures of ( 11 and 12) have been determined by X-ray diffraction techniques. Evidently, in the macrocyclic ring of the compound ( 11), there are two three-centered (bifurcate) N-H⋯O/N-H⋯N hydrogen bonds, while compound ( 12) has two intramolecular N-H⋯O bonds. The relative radii of macrocyclic hole sizes of the compounds ( 11 and 12) are 1.25 and 1.10 Å, respectively. The structures of the new compounds ( 9- 12) have also been examined by FTIR, 1H-, 13C-, 31P-NMR, MS and elemental analysis. Compound ( 11) crystallizes in the Pcab space group with a=9.8474(13), b=18.466(2), c=38.9375(19) Å, V=7080.7(14) Å 3, Z=8 and Dx=1.317 g cm -3, while compound ( 12) crystallizes in P-1 space group with a=9.3724(5), b=11.2613(9), c=20.401(2) Å, ?=93.177(8), ?=102.115(7), ?=105.360(5)°, V=2016.0(3) Å 3, Z=2 and Dx=1.268 g cm -3. The structures of ( 11 and 12) consist of nearly planar and non-planar trimeric phosphazene rings with spiro-cyclic bulky N 2O 3 and N 2O 2 macrocycles, respectively.
Derived enriched uranium market
Rutkowski
1996-01-01
The potential impact on the uranium market of highly enriched uranium from nuclear weapons dismantling in the Russian Federation and the USA is analyzed. Uranium supply, conversion, and enrichment factors are outlined for each country; inventories are also listed. The enrichment component and conversion components are expected to cause little disruption to uranium markets. The uranium component of Russian derived
Biotechnology and derived products
Technology Transfer Automated Retrieval System (TEKTRAN)
Microorganisms able to infect and kill insect pests, metabolites from plants and microorganisms, and transgenic crops are biotechnologically derived products that are being promoted for use to control insect pests in lieu of chemical insecticides. Products based on these technologies effectively co...
Deriving force from inductance
M. de Almeida Bueno; A. K. T. Assis
1998-01-01
The correctness of calculating the force on current carrying circuits by taking the derivative of the inductance coefficient of the circuits is shown even in the case of a single closed circuit, contrary to the opinion of some authors. This demonstration is illustrated with the force exerted by a cylinder with poloidal current on an infinitesimal strip belonging to the
Synthesis and thermal stability of carborane containing phosphazenes
NASA Technical Reports Server (NTRS)
Fewell, L. L.; Basi, R. J.; Parker, J. A.
1983-01-01
Carborane substituted polyphosphazenes were prepared by the thermal polymerization of phenyl-carboranyl penta chlorocyclotriphosphazene. Successive isothermal vacuum pyrolyses were conducted on the polymer and examined for structural changes by infrared spectroscopy. The degradation products were ascertained by gas chromatography-mass spectrometric analysis. It was found that the presence of the carborane group improves the thermal stability of the polymer by retarding the ring chain equilibrium processes of decomposition.
Second virial coefficient of poly[(4-ethylphenoxy)(phenoxy)phosphazene
NASA Astrophysics Data System (ADS)
Wohlfarth, Ch.
This document is part of Subvolume D2 'Polymer Solutions - Physical Properties and their Relations I (Thermodynamic Properties: PVT -Data and miscellaneous Properties of polymer Solutions) of Volume 6 `Polymers' of Landolt-Börnstein - Group VIII `Advanced Materials and Technologies'.
Synthesis and thermal stability of carborane-containing phosphazenes
NASA Technical Reports Server (NTRS)
Fewell, L. L.; Parker, J. A.; Basi, R. J.
1983-01-01
Carborane-substituted polyphosphazenes were prepared by the thermal polymerization of phenyl-carboranyl pentachlorocylotriphosphazene. Successive isothermal vacuum pyrolyses were conducted on the polymer and examined for structural changes by infrared spectroscopy. The degradation products were ascertained by gas chromatography-mass spectrometric analysis. It was found that the presence of the carborane group improves the thermal stability of the polymer by retarding the ring-chain equilibrium processes of decomposition. Previously announced in STAR as A83-21034
Second virial coefficient of poly[(2-naphthylenyloxy)(phenoxy)phosphazene
NASA Astrophysics Data System (ADS)
Wohlfarth, Ch.
This document is part of Subvolume D2 'Polymer Solutions - Physical Properties and their Relations I (Thermodynamic Properties: PVT -Data and miscellaneous Properties of polymer Solutions) of Volume 6 `Polymers' of Landolt-Börnstein - Group VIII `Advanced Materials and Technologies'.
Thermal degradation chemistry of poly[bis(phenoxy)phosphazene
Maynard, Shawn Joseph
1989-01-01
the model compound studies and from the degradation of PBPP suggests that phenyl migration occurs at some stage during degradation. Some of these findings are in disagreement with previously reported studies. P solution-state and solid-state NMR... CONCLUSIONS REFERENCES Y ITA Dynamic degradation of PBPP samples ~othermal degradation of model compound samples. P Solution-State NMR characterization of PBPP samples. Isothermal degradation of PBPP samples Solution-State hydrolysis of PBPP samples...
Gupta, Yashdeep; Singla, Gaurav; Singla, Rajiv
2015-01-01
Amyloidosis is the term for diseases caused by the extracellular deposition of insoluble polymeric protein fibrils in tissues and organs. Insulin-derived amyloidosis is a rare, yet significant complication of insulin therapy. Insulin-derived amyloidosis at injection site can cause poor glycemic control and increased insulin dose requirements because of the impairment in insulin absorption, which reverse on change of injection site and/or excision of the mass. This entity should be considered and assessed by histopathology and immunohistochemistry, in patients with firm/hard local site reactions, which do not regress after cessation of insulin injection at the affected site. Search strategy: PubMed was searched with terms “insulin amyloidosis”. Full text of articles available in English was reviewed. Relevant cross references were also reviewed. Last search was made on October 15, 2014. PMID:25593849
Fractional Derivative Cosmology
Mark D. Roberts
2009-09-07
The degree by which a function can be differentiated need not be restricted to integer values. Usually most of the field equations of physics are taken to be second order, curiosity asks what happens if this is only approximately the case and the field equations are nearly second order. For Robertson-Walker cosmology there is a simple fractional modification of the Friedman and conservation equations. In general fractional gravitational equations similar to Einstein's are hard to define as this requires fractional derivative geometry. What fractional derivative geometry might entail is briefly looked at and it turns out that even asking very simple questions in two dimensions leads to ambiguous or intractable results. A two dimensional line element which depends on the Gamma-function is looked at.
Notion of a virtual derivative
Gintaras Valiukevicius
2011-04-12
Diagrams as a graphic expresion of derivatives is proposed for calculation of derivatives for composed function. The concret diagram is understood as a virtual derivative in contrast of concret derivative. In polynomial expression of functions derivative the concret derivative will be every monomic member, and the virtual derivative represent the sum of similar monomic members. The word virtual denotes that we dont need to know every virtual derivative, we don't write all the sequence of these virtual derivatives, and simply pick the needed one. This is in contrast of tradition to write the whole algebraic expresion as a denotion of whole function's derivative. Such graphic expresion can be helpful in the problems of differential geometry, in the various asymptotic expantions, also in the solution of some differential equations.
NSDL National Science Digital Library
Karen Salvage
This exercise begins with a demonstration of fluid flow through porous sediment using a constant head permeameter, with the students conducting the experiment and collecting the data. The demo is followed by a Think-Pair-Share exercise in which the question is posed to the class: "What could we change in order to increase flow through the system?" The class then works through their brainstormed list of ideas, discussing each and evaluating whether it is correct or a misconception. The students derive Darcy's Law qualitatively, based upon the results of the Think-Pair-Share exercise and discussions.
Acquiring Knowledge of Derived Nominals and Derived Adjectives in Context
ERIC Educational Resources Information Center
Marinellie, Sally A.; Kneile, Lynn A.
2012-01-01
Purpose: This research investigated children's ability to acquire semantic and syntactic knowledge of derived nominals and derived adjectives in the context of short passages. The study also investigated the relation of morphological awareness and the ability to acquire knowledge of derived words in context. Method: A total of 106 children in…
6-Bromocholesterol derivatives
Flanagan, R.J.
1984-02-07
Novel 6-bromo derivatives of cholesterol have the formula 3-(R-O-),6-BR,17-((H3C-)2-HC-H2C-H2C-H2C-HC(-CH3)-)-ESTR-5-ENE Such compounds are prepared from the known 6-iodocholesterol by treatment with cuprous bromide. These compounds, labelled with radioisotopes of Br-82 or Br-77, are localized in the adrenal, mammary and ovary tissue of female mammals and in the adrenal or prostate tissue of males when administered to such individuals. This provides a method for imaging adrenal, ovary or prostate tissue which is superior to use of the prior art 6-iodo-cholesterol.
Optimal Investment in Derivative Securities
Peter Carr; Xing Jin; Dilip B. Madan
2000-01-01
We consider the problem of optimal investment in a risky asset, and in derivatives written on the price process of this asset, when the underlying asset price process is a pure jump Levy process. The duality approach of Karatzas and Shreve is used to derive the optimal consumption and investment plans. In our economy, the optimal derivative payoff can be
Mohsen Alishahiha; Sunil Mukhi
2008-09-05
Starting with the N=8 supersymmetric Yang-Mills theory on D2-branes and incorporating higher-derivative corrections to lowest nontrivial order, we perform a duality to derive the Lorentzian 3-algebra theory along with a set of derivative corrections. We find that these corrections can be expressed entirely in terms of intrinsic 3-algebra quantities: the 3-bracket and covariant derivatives. Our analysis is performed for both bosonic and fermionic terms. We conjecture that the derivative corrections we obtain are relevant for Euclidean 3-algebra theories as well.
Theoretical study of the cyclotriphosphazenes importance of phosphorus d orbitals
NASA Astrophysics Data System (ADS)
Haddon, R. C.
1985-10-01
The nature of the bonding and the degree of delocalization in the phosphazenes has been controversial for more than twenty five years. An Important aspect of this discussion revolves around the question of phosphorus d-orbital participation in the phosphazene bond. In the present communication I report theoretical calculations on a series of cyclotriphosphazene derivatives which strongly suggest that from a structural point of view, phosphorus d orbitals are significant participants in the ring bonds.
Deriving bedform phase diagrams
NSDL National Science Digital Library
Tom Hickson
Students prepare for this activity by working with a unidirectional flume with a sand bed. We adjust water depth, flow velocity, and channel slope to achieve a range of bed states, in an effort for them to understand the controls on bedforms. This portion of the activity could be done in lecture or via another exercise that makes use of digital video of actual experiments. The activity itself is a jigsaw: students form groups of three, each group responsible for plotting depth vs. velocity plots of bedform state for a single sand grain size range (0.10-0.14 mm, 0.5-0.64 mm, and 1.3-1.8 mm). These data are provided to them as Excel files and the data were directly 'stolen' from the original depth vs. velocity plots in Middleton and Southard (1984), Mechanics of Sediment Movement, SEPM Short Course Number 3. Datathief software (available free on the web) was used to steal the data. The data are arranged in columns: depth, velocity, and bedform type. Students must plot each of the different bedform types with a different symbol, then they have to define field boundaries. It is critical that they have never seen the original plots in their textbook. The goal is for them to derive them on their own, not to regurgitate what is in their textbook or elsewhere. After they complete their plots for each grain size range, the groups re-arrange themselves into groups of three with one representative from each of the grain size groups. They then must try to evaluate the effects of changing grain size on bedform state. Finally, after completing the exercise, the bedform analysis is linked to the cross stratification that is produced under conditions of high sediment fallout rates and the given bed state. The activity gives students practice working with realistic datasets, exposure to the role of physical modeling in sedimentary geology, and a chance to plot and interpret real data. Furthermore, it really solidifies the link between cross stratification and its dynamic interpretation from the rock record.
Finite investigations of transfinite derivations
G. E. Mints
1978-01-01
?-derivations of arithmetic formulas are analyzed. A primitive recursive normalization operator E is constructed in the first part. It cut-eliminates not only recursively described derivations (i.e., well-founded proof-figures) but also arbitrary (not necessarily well-founded) proof-figures constructed from an axiom by derivation rules. This permits us to apply E in the theory of models, Its application in the theory of proofs
Optimal investment in derivative securities
Peter Carr; Xing Jin; Dilip B. Madan
2001-01-01
. We consider the problem of optimal investment in a risky asset, and in derivatives written on the price process of this asset,\\u000a when the underlying asset price process is a pure jump Lévy process. The duality approach of Karatzas and Shreve is used to\\u000a derive the optimal consumption and investment plans. In our economy, the optimal derivative payoff can
Limits and Derivatives: The Derivative as a Function
NSDL National Science Digital Library
Michael Freeze
Sketch the graph of the derivative of a geometrically represented function;Explain the correspondence between the sign of the derivative on an interval and the monotonicity of the function on that interval. Classify the basic ways in which a function may fail to be differentiable.
Elementary derivation of Kepler's laws
Erich Vogt
1996-01-01
A simple derivation of all three so-called Kepler laws is presented in which the orbits, bound and unbound, follow directly and immediately from conservation of energy and angular momentum. The intent is to make this crowning achievement of Newtonian mechanics easily accessible to students in introductory physics courses. The method is also extended to simplify the derivation of the Rutherford
Hyperplane sections and derived categories
NASA Astrophysics Data System (ADS)
Kuznetsov, A. G.
2006-06-01
We give a generalization of the theorem of Bondal and Orlov about the derived categories of coherent sheaves on intersections of quadrics, revealing the relation of this theorem to projective duality. As an application, we describe the derived categories of coherent sheaves on Fano 3-folds of index 1 and degrees 12, 16 and 18.
Asset Liability Management Using Derivatives
N. E. Frangos; S. D. Vrontos; A. N. Yannacopoulos
We show how derivatives can be used for asset liability management when the stock price process is driven by Brownian motion. We generalize some results that have been derived under the assumption of Brownian motion, for difierent types of options, and we show how they can be used for e-cient and with low transactions costs asset liability management. We construct
12 CFR 163.172 - Financial derivatives.
Code of Federal Regulations, 2014 CFR
2014-01-01
...2014-01-01 2014-01-01 false Financial derivatives. 163.172 Section 163.172 Banks...Management Policies § 163.172 Financial derivatives. (a) What is a financial derivative? A financial derivative is a...
12 CFR 563.172 - Financial derivatives.
Code of Federal Regulations, 2014 CFR
2014-01-01
...2014-01-01 2012-01-01 true Financial derivatives. 563.172 Section 563.172 Banks...Management Policies § 563.172 Financial derivatives. (a) What is a financial derivative? A financial derivative is a...
12 CFR 390.352 - Financial derivatives.
Code of Federal Regulations, 2012 CFR
2012-01-01
...2012-01-01 2012-01-01 false Financial derivatives. 390.352 Section 390.352 Banks...Associations-Operations § 390.352 Financial derivatives. (a) What is a financial derivative? A financial derivative is a...
12 CFR 163.172 - Financial derivatives.
Code of Federal Regulations, 2012 CFR
2012-01-01
...2012-01-01 2012-01-01 false Financial derivatives. 163.172 Section 163.172 Banks...Management Policies § 163.172 Financial derivatives. (a) What is a financial derivative? A financial derivative is a...
12 CFR 563.172 - Financial derivatives.
Code of Federal Regulations, 2012 CFR
2012-01-01
...2012-01-01 2012-01-01 false Financial derivatives. 563.172 Section 563.172 Banks...Management Policies § 563.172 Financial derivatives. (a) What is a financial derivative? A financial derivative is a...
12 CFR 390.352 - Financial derivatives.
Code of Federal Regulations, 2014 CFR
2014-01-01
...2014-01-01 2014-01-01 false Financial derivatives. 390.352 Section 390.352 Banks...Associations-Operations § 390.352 Financial derivatives. (a) What is a financial derivative? A financial derivative is a...
12 CFR 163.172 - Financial derivatives.
Code of Federal Regulations, 2013 CFR
2013-01-01
...2013-01-01 2013-01-01 false Financial derivatives. 163.172 Section 163.172 Banks...Management Policies § 163.172 Financial derivatives. (a) What is a financial derivative? A financial derivative is a...
12 CFR 390.352 - Financial derivatives.
Code of Federal Regulations, 2013 CFR
2013-01-01
...2013-01-01 2013-01-01 false Financial derivatives. 390.352 Section 390.352 Banks...Associations-Operations § 390.352 Financial derivatives. (a) What is a financial derivative? A financial derivative is a...
12 CFR 563.172 - Financial derivatives.
Code of Federal Regulations, 2010 CFR
2010-01-01
...2010-01-01 2010-01-01 false Financial derivatives. 563.172 Section 563.172 Banks...Management Policies § 563.172 Financial derivatives. (a) What is a financial derivative? A financial derivative is a...
12 CFR 563.172 - Financial derivatives.
Code of Federal Regulations, 2011 CFR
2011-01-01
...2011-01-01 2011-01-01 false Financial derivatives. 563.172 Section 563.172 Banks...Management Policies § 563.172 Financial derivatives. (a) What is a financial derivative? A financial derivative is a...
12 CFR 563.172 - Financial derivatives.
Code of Federal Regulations, 2013 CFR
2013-01-01
...2013-01-01 2012-01-01 true Financial derivatives. 563.172 Section 563.172 Banks...Management Policies § 563.172 Financial derivatives. (a) What is a financial derivative? A financial derivative is a...
Quinazoline derivatives: synthesis and bioactivities
2013-01-01
Owing to the significant biological activities, quinazoline derivatives have drawn more and more attention in the synthesis and bioactivities research. This review summarizes the recent advances in the synthesis and biological activities investigations of quinazoline derivatives. According to the main method the authors adopted in their research design, those synthetic methods were divided into five main classifications, including Aza-reaction, Microwave-assisted reaction, Metal-mediated reaction, Ultrasound-promoted reaction and Phase-transfer catalysis reaction. The biological activities of the synthesized quinazoline derivatives also are discussed. PMID:23731671
Complex higher order derivative theories
Margalli, Carlos A.; Vergara, J. David [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-543, Mexico 04510 DF (Mexico)
2012-08-24
In this work is considered a complex scalar field theory with higher order derivative terms and interactions. A procedure is developed to quantize consistently this system avoiding the presence of negative norm states. In order to achieve this goal the original real scalar high order field theory is extended to a complex space attaching a complex total derivative to the theory. Next, by imposing reality conditions the complex theory is mapped to a pair of interacting real scalar field theories without the presence of higher derivative terms.
Elevation Derivatives for National Applications
U.S. Geological Survey
2005-01-01
The Elevation Derivatives for National Applications (EDNA) project is a multi-agency effort to develop standard topographically derived layers for use in hydrologic and environmental modeling. The EDNA takes advantage of the seamless and filtered characteristics for the National Elevation Dataset (NED) to create a hydrologically conditioned Digital Elevation Model (DEM) useful for modeling applications. The goals of the project are to create a hydrologically conditioned DEM and systematically extract a set of standard derivatives that can be used to facilitate data integration with other U.S. Geological Survey (USGS) framework data sets such as the National Hydrography Dataset (NHD) and the Watershed Boundaries Dataset (WBD).
MCR Synthesis of Praziquantel Derivatives
Liu, Haixia; William, Samia; Herdtweck, Eberhardt; Botros, Sanaa; Dömling, Alexander
2013-01-01
Schistosomiasis, a high volume neglected tropical disease affecting more than 200 million people worldwide, can only be effectively treated by the tetrahydroisoquinoline drug praziquantel (PZQ). Herein, we describe an efficient approach to access PZQ derivatives by the Ugi 4-component reaction followed by the Pictet-Spengler reaction in a two-step, one-pot procedure. 30 Novel PZQ derivatives are described based on the Ugi 4-component reaction and an X-ray structure of a novel derivative revealing different conformation compared with PZQ is discussed. Several analogues comparable in activity to the drug PZQ have been identified based on an in vitro Schistosoma mansoni worm viability assay. PMID:22151001
Limonoid derivatives from Cedrelopsis grevei
Dulcie Mulholland; Hamdani Mahomed; Maria Kotsos; Milijaona Randrianarivelojosia; Catherine Lavaud; Georges Massiot; Jean-Marc Nuzillard
1999-01-01
The stem bark of Cedrelopsis grevei has yielded ?-amyrin and two novel limonoid derivatives, the pentanortriterpenoid, cedmilinol, and the hexanortriterpenoid, cedmiline. Structures were elucidated using NMR analysis and the “Logic for Structure Determination” program.
Bioactive Benzofuran derivatives: A review.
Khanam, Hena; Shamsuzzaman
2014-11-22
In nature's collection of biologically active heterocycles, benzofuran derivatives constitute a major group. The broad spectrum of pharmacological activity in individual benzofurans indicates that this series of compounds is of an undoubted interest. Benzofuran and its derivatives have attracted medicinal chemists and pharmacologists due to their pronounced biological activities and their potential applications as pharmacological agents. Due to the wide range of biological activities of benzofurans, their structure activity relationships have generated interest among medicinal chemists, and this has culminated in the discovery of several lead molecules in numerous disease conditions. The outstanding development of benzofuran derivatives in diverse diseases in very short span of time proves its magnitude for medicinal chemistry research. The present review is endeavour to highlight the progress in the various pharmacological activities of benzofuran derivatives in the current literature with an update of recent research findings on this nucleus. PMID:25482554
Organic derivatives of zirconium phosphate
Fine, Steven Beryl
1980-01-01
ORGANIC DERIVATIVES OF ZIRCONIUM PHOSPHATE A Thesis by STEVEN BERYL FINE Submitted to the Graduate College of Texas AAM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE December 1980 Major Subject...: Chemistry ORGANIC DERIVATIVES OF ZIRCONIUM PHOSPHATE A Thesis by STEVEN BERYL FINE Approved as to style and content by: Dr. A raham Clearfield (c irman) Dr. Kurt Irgolic (member) 4~~@4 Dr. Martha Scott (member) Dr. C. S. Giam (department head...
Radiative $?$ decays with derivative interactions
Francesco Giacosa; Giuseppe Pagliara
2008-10-14
We study the line shapes of radiative $\\phi$-decays involving virtual $f_{0}(980)$ and $a_{0}(980)$ mesons which decay, via derivative couplings, to $\\pi^{0}\\pi^{0}$ and $\\pi^{0}\\eta$ respectively. After developing the formalism for derivative interactions at one-loop level, we show that they can reproduce the measured peaked line shapes of $\\phi$-decays without including kaon loops.
21 CFR 184.1685 - Rennet (animal-derived) and chymosin preparation (fermentation-derived).
Code of Federal Regulations, 2010 CFR
2010-04-01
...animal-derived) and chymosin preparation (fermentation-derived). 184.1685 Section...animal-derived) and chymosin preparation (fermentation-derived). (a)(1...4.23.4). It is derived, via fermentation, from a nonpathogenic and...
21 CFR 184.1685 - Rennet (animal-derived) and chymosin preparation (fermentation-derived).
Code of Federal Regulations, 2012 CFR
2012-04-01
...animal-derived) and chymosin preparation (fermentation-derived). 184.1685 Section...animal-derived) and chymosin preparation (fermentation-derived). (a)(1...4.23.4). It is derived, via fermentation, from a nonpathogenic and...
21 CFR 184.1685 - Rennet (animal-derived) and chymosin preparation (fermentation-derived).
Code of Federal Regulations, 2011 CFR
2011-04-01
...animal-derived) and chymosin preparation (fermentation-derived). 184.1685 Section...animal-derived) and chymosin preparation (fermentation-derived). (a)(1...4.23.4). It is derived, via fermentation, from a nonpathogenic and...
21 CFR 184.1685 - Rennet (animal-derived) and chymosin preparation (fermentation-derived).
Code of Federal Regulations, 2014 CFR
2014-04-01
...animal-derived) and chymosin preparation (fermentation-derived). 184.1685 Section...animal-derived) and chymosin preparation (fermentation-derived). (a)(1...4.23.4). It is derived, via fermentation, from a nonpathogenic and...
21 CFR 184.1685 - Rennet (animal-derived) and chymosin preparation (fermentation-derived).
Code of Federal Regulations, 2013 CFR
2013-04-01
...animal-derived) and chymosin preparation (fermentation-derived). 184.1685 Section...animal-derived) and chymosin preparation (fermentation-derived). (a)(1...4.23.4). It is derived, via fermentation, from a nonpathogenic and...
Derivative-Free Optimization Proximal Point Methods Derivative-Free Proximal Point Conclusion Derivative-Free Optimization via Proximal Point Methods Yves Lucet & Warren Hare July 24, 2013 1 / 26 #12;Derivative-Free Optimization Proximal Point Methods Derivative-Free Proximal Point Conclusion Outline 1
Sigman, Michael E.; Dindal, Amy B.
2003-11-11
Described is a method for producing copolymerized sol-gel derived sorbent particles for the production of copolymerized sol-gel derived sorbent material. The method for producing copolymerized sol-gel derived sorbent particles comprises adding a basic solution to an aqueous metal alkoxide mixture for a pH.ltoreq.8 to hydrolyze the metal alkoxides. Then, allowing the mixture to react at room temperature for a precalculated period of time for the mixture to undergo an increased in viscosity to obtain a desired pore size and surface area. The copolymerized mixture is then added to an immiscible, nonpolar solvent that has been heated to a sufficient temperature wherein the copolymerized mixture forms a solid upon the addition. The solid is recovered from the mixture, and is ready for use in an active sampling trap or activated for use in a passive sampling trap.
Magnetic cellulose-derivative structures
Walsh, M.A.; Morris, R.S.
1986-09-16
Structures to serve as selective magnetic sorbents are formed by dissolving a cellulose derivative such as cellulose triacetate in a solvent containing magnetic particles. The resulting solution is sprayed as a fine mist into a chamber containing a liquid coagulant such as n-hexane in which the cellulose derivative is insoluble but in which the coagulant is soluble or miscible. On contact with the coagulant, the mist forms free-flowing porous magnetic microspheric structures. These structures act as containers for the ion-selective or organic-selective sorption agent of choice. Some sorption agents can be incorporated during the manufacture of the structure. 3 figs.
Empirically derived injury prevention rules.
Peterson, L; Schick, B
1993-01-01
This study describes a set of empirically derived safety rules that if followed, would have prevented the occurrence of minor injuries. Epidemiologists have criticized behavioral interventions as increasing "safe" behavior but failing to demonstrate a decrease in injury. The present study documents retrospectively the link between safe behavior and injury. It demonstrates that these empirically derived rules are very similar to rules for the prevention of serious injury. The study also shows that these rules are not widely accepted and implemented by parents. Suggestions for future research in this area are advanced. PMID:8307829
Magnetic cellulose-derivative structures
Walsh, Myles A. (Falmouth, MA); Morris, Robert S. (Fairhaven, MA)
1986-09-16
Structures to serve as selective magnetic sorbents are formed by dissolving a cellulose derivative such as cellulose triacetate in a solvent containing magnetic particles. The resulting solution is sprayed as a fine mist into a chamber containing a liquid coagulant such as n-hexane in which the cellulose derivative is insoluble but in which the coagulant is soluble or miscible. On contact with the coagulant, the mist forms free-flowing porous magnetic microspheric structures. These structures act as containers for the ion-selective or organic-selective sorption agent of choice. Some sorbtion agents can be incorporated during the manufacture of the structure.
Code of Federal Regulations, 2012 CFR
2012-07-01
...2012-07-01 false Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic acid derivative, ammonium salt (generic). 721...721.10039 Diethoxybenzenamine derivative, diazotized, coupled with...
Code of Federal Regulations, 2010 CFR
2010-07-01
...2010-07-01 false Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic acid derivative, ammonium salt (generic). 721...721.10039 Diethoxybenzenamine derivative, diazotized, coupled with...
Quantum White Noise Derivatives and Implementation Problem
Obata, Nobuaki
. . Quantum White Noise Derivatives and Implementation Problem On the occasion of thier 60th, 2009 Nobuaki Obata (GSIS, Tohoku University) Quantum White Noise Derivatives and Implementation Problem (GSIS, Tohoku University) Quantum White Noise Derivatives and Implementation Problem Fukuoka, November
40 CFR 721.1820 - Bisphenol derivative.
Code of Federal Regulations, 2014 CFR
2014-07-01
...2014-07-01 2014-07-01 false Bisphenol derivative. 721.1820 Section 721...Chemical Substances § 721.1820 Bisphenol derivative. (a) Chemical substance...chemical substance identified generically as bisphenol derivative (PMN No....
40 CFR 721.1820 - Bisphenol derivative.
Code of Federal Regulations, 2013 CFR
2013-07-01
...2013-07-01 2013-07-01 false Bisphenol derivative. 721.1820 Section 721...Chemical Substances § 721.1820 Bisphenol derivative. (a) Chemical substance...chemical substance identified generically as bisphenol derivative (PMN No....
18 CFR 1301.65 - Derivative classification.
Code of Federal Regulations, 2013 CFR
2013-04-01
...2013-04-01 2012-04-01 true Derivative classification. 1301.65 Section...Classified Information § 1301.65 Derivative classification. (a) In accordance...apply to the source information, is derivative classification. (1)...
45 CFR 601.5 - Derivative classification.
Code of Federal Regulations, 2014 CFR
2014-10-01
...2014-10-01 2014-10-01 false Derivative classification. 601.5 Section...NATIONAL SECURITY INFORMATION § 601.5 Derivative classification. Distinct...authority. (a) If a person who applies derivative classification markings...
40 CFR 721.9658 - Thiadiazole derivative.
Code of Federal Regulations, 2013 CFR
2013-07-01
...2013-07-01 false Thiadiazole derivative. 721.9658 Section 721.9658...Substances § 721.9658 Thiadiazole derivative. (a) Chemical substance and significant...substance identified as a thiadiazole derivative (PMN P-94-1631) is subject...
45 CFR 601.5 - Derivative classification.
Code of Federal Regulations, 2011 CFR
2011-10-01
...2011-10-01 2011-10-01 false Derivative classification. 601.5 Section...NATIONAL SECURITY INFORMATION § 601.5 Derivative classification. Distinct...authority. (a) If a person who applies derivative classification markings...
46 CFR 503.55 - Derivative classification.
Code of Federal Regulations, 2014 CFR
2014-10-01
...2014-10-01 2014-10-01 false Derivative classification. 503.55 Section...Information Security Program § 503.55 Derivative classification. (a) In...apply to the source information, is derivative classification. (1)...
45 CFR 601.5 - Derivative classification.
Code of Federal Regulations, 2013 CFR
2013-10-01
...2013-10-01 2013-10-01 false Derivative classification. 601.5 Section...NATIONAL SECURITY INFORMATION § 601.5 Derivative classification. Distinct...authority. (a) If a person who applies derivative classification markings...
40 CFR 721.1820 - Bisphenol derivative.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 2012-07-01 false Bisphenol derivative. 721.1820 Section 721.1820...Substances § 721.1820 Bisphenol derivative. (a) Chemical substance and significant...substance identified generically as bisphenol derivative (PMN No. P-92-509) is...
46 CFR 503.55 - Derivative classification.
Code of Federal Regulations, 2011 CFR
2011-10-01
...2011-10-01 2011-10-01 false Derivative classification. 503.55 Section...Information Security Program § 503.55 Derivative classification. (a) In...apply to the source information, is derivative classification. (1)...
28 CFR 17.26 - Derivative classification.
Code of Federal Regulations, 2010 CFR
2010-07-01
...2010-07-01 2010-07-01 false Derivative classification. 17.26 Section...Classified Information § 17.26 Derivative classification. (a) Persons...classification guides. (b) Persons who apply derivative classification markings shall...
28 CFR 17.26 - Derivative classification.
Code of Federal Regulations, 2013 CFR
2013-07-01
...2013-07-01 2013-07-01 false Derivative classification. 17.26 Section...Classified Information § 17.26 Derivative classification. (a) Persons...classification guides. (b) Persons who apply derivative classification markings shall...
40 CFR 721.9658 - Thiadiazole derivative.
Code of Federal Regulations, 2012 CFR
2012-07-01
...2012-07-01 false Thiadiazole derivative. 721.9658 Section 721.9658...Substances § 721.9658 Thiadiazole derivative. (a) Chemical substance and significant...substance identified as a thiadiazole derivative (PMN P-94-1631) is subject...
40 CFR 721.1820 - Bisphenol derivative.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 2011-07-01 false Bisphenol derivative. 721.1820 Section 721.1820...Substances § 721.1820 Bisphenol derivative. (a) Chemical substance and significant...substance identified generically as bisphenol derivative (PMN No. P-92-509) is...
46 CFR 503.55 - Derivative classification.
Code of Federal Regulations, 2013 CFR
2013-10-01
...2013-10-01 2013-10-01 false Derivative classification. 503.55 Section...Information Security Program § 503.55 Derivative classification. (a) In...apply to the source information, is derivative classification. (1)...
18 CFR 1301.65 - Derivative classification.
Code of Federal Regulations, 2012 CFR
2012-04-01
...2012-04-01 2012-04-01 false Derivative classification. 1301.65 Section...Classified Information § 1301.65 Derivative classification. (a) In accordance...apply to the source information, is derivative classification. (1)...
46 CFR 503.55 - Derivative classification.
Code of Federal Regulations, 2012 CFR
2012-10-01
...2012-10-01 2012-10-01 false Derivative classification. 503.55 Section...Information Security Program § 503.55 Derivative classification. (a) In...apply to the source information, is derivative classification. (1)...
32 CFR 2001.22 - Derivative classification.
Code of Federal Regulations, 2012 CFR
2012-07-01
...2012-07-01 2012-07-01 false Derivative classification. 2001.22 Section...Identification and Markings § 2001.22 Derivative classification. (a) General... (b) Identity of persons who apply derivative classification markings....
40 CFR 721.5913 - Phenothiazine derivative.
Code of Federal Regulations, 2011 CFR
2011-07-01
...2011-07-01 false Phenothiazine derivative. 721.5913 Section 721.5913...Substances § 721.5913 Phenothiazine derivative. (a) Chemical substance and significant...identified generically as a phenothiazine derivative (PMN P-96-813) is subject...
40 CFR 721.5913 - Phenothiazine derivative.
Code of Federal Regulations, 2013 CFR
2013-07-01
...2013-07-01 false Phenothiazine derivative. 721.5913 Section 721.5913...Substances § 721.5913 Phenothiazine derivative. (a) Chemical substance and significant...identified generically as a phenothiazine derivative (PMN P-96-813) is subject...
32 CFR 2001.22 - Derivative classification.
Code of Federal Regulations, 2013 CFR
2013-07-01
...2013-07-01 2013-07-01 false Derivative classification. 2001.22 Section...Identification and Markings § 2001.22 Derivative classification. (a) General... (b) Identity of persons who apply derivative classification markings....
32 CFR 2001.22 - Derivative classification.
Code of Federal Regulations, 2011 CFR
2011-07-01
...2011-07-01 2011-07-01 false Derivative classification. 2001.22 Section...Identification and Markings § 2001.22 Derivative classification. (a) General... (b) Identity of persons who apply derivative classification markings....
46 CFR 503.55 - Derivative classification.
Code of Federal Regulations, 2010 CFR
2010-10-01
...2010-10-01 2010-10-01 false Derivative classification. 503.55 Section...Information Security Program § 503.55 Derivative classification. (a) In...apply to the source information, is derivative classification. (1)...
28 CFR 17.26 - Derivative classification.
Code of Federal Regulations, 2011 CFR
2011-07-01
...2011-07-01 2011-07-01 false Derivative classification. 17.26 Section...Classified Information § 17.26 Derivative classification. (a) Persons...classification guides. (b) Persons who apply derivative classification markings shall...
28 CFR 17.26 - Derivative classification.
Code of Federal Regulations, 2012 CFR
2012-07-01
...2012-07-01 2012-07-01 false Derivative classification. 17.26 Section...Classified Information § 17.26 Derivative classification. (a) Persons...classification guides. (b) Persons who apply derivative classification markings shall...
40 CFR 721.9658 - Thiadiazole derivative.
Code of Federal Regulations, 2011 CFR
2011-07-01
...2011-07-01 false Thiadiazole derivative. 721.9658 Section 721.9658...Substances § 721.9658 Thiadiazole derivative. (a) Chemical substance and significant...substance identified as a thiadiazole derivative (PMN P-94-1631) is subject...
45 CFR 601.5 - Derivative classification.
Code of Federal Regulations, 2012 CFR
2012-10-01
...2012-10-01 2012-10-01 false Derivative classification. 601.5 Section...NATIONAL SECURITY INFORMATION § 601.5 Derivative classification. Distinct...authority. (a) If a person who applies derivative classification markings...
45 CFR 601.5 - Derivative classification.
Code of Federal Regulations, 2010 CFR
2010-10-01
...2010-10-01 2010-10-01 false Derivative classification. 601.5 Section...NATIONAL SECURITY INFORMATION § 601.5 Derivative classification. Distinct...authority. (a) If a person who applies derivative classification markings...
40 CFR 721.9658 - Thiadiazole derivative.
Code of Federal Regulations, 2010 CFR
2010-07-01
...2010-07-01 false Thiadiazole derivative. 721.9658 Section 721.9658...Substances § 721.9658 Thiadiazole derivative. (a) Chemical substance and significant...substance identified as a thiadiazole derivative (PMN P-94-1631) is subject...
40 CFR 721.1820 - Bisphenol derivative.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 2010-07-01 false Bisphenol derivative. 721.1820 Section 721.1820...Substances § 721.1820 Bisphenol derivative. (a) Chemical substance and significant...substance identified generically as bisphenol derivative (PMN No. P-92-509) is...
32 CFR 2001.22 - Derivative classification.
Code of Federal Regulations, 2014 CFR
2014-07-01
...2014-07-01 2014-07-01 false Derivative classification. 2001.22 Section...Identification and Markings § 2001.22 Derivative classification. (a) General... (b) Identity of persons who apply derivative classification markings....
18 CFR 1301.65 - Derivative classification.
Code of Federal Regulations, 2014 CFR
2014-04-01
...2014-04-01 2014-04-01 false Derivative classification. 1301.65 Section...Classified Information § 1301.65 Derivative classification. (a) In accordance...apply to the source information, is derivative classification. (1)...
40 CFR 721.5913 - Phenothiazine derivative.
Code of Federal Regulations, 2010 CFR
2010-07-01
...2010-07-01 false Phenothiazine derivative. 721.5913 Section 721.5913...Substances § 721.5913 Phenothiazine derivative. (a) Chemical substance and significant...identified generically as a phenothiazine derivative (PMN P-96-813) is subject...
Quaternion Derivatives: The GHR Calculus
Dongpo Xu; Cyrus Jahanchahi; Clive C. Took; Danilo P. Mandic
2014-09-25
Quaternion derivatives in the mathematical literature are typically defined only for analytic (regular) functions. However, in engineering problems, functions of interest are often real-valued and thus not analytic, such as the standard cost function. The HR calculus is a convenient way to calculate formal derivatives of both analytic and non-analytic functions of quaternion variables, however, both the HR and other functional calculus in quaternion analysis have encountered an essential technical obstacle, that is, the traditional product rule is invalid due to the non- commutativity of the quaternion algebra. To address this issue, a generalized form of the HR derivative is proposed based on a general orthogonal system. The so introduced generalization, called the generalized HR (GHR) calculus, encompasses not just the left- and right-hand versions of quaternion derivative, but also enables solutions to some long standing problems, such as the novel product rule, the chain rule, the mean-valued theorem and Taylor's theorem. At the core of the proposed approach is the quaternion rotation, which can naturally be applied to other functional calculi in non-commutative settings. Examples on using the GHR calculus in adaptive signal processing support the analysis.
Informational derivation of quantum theory
Chiribella, Giulio; D'Ariano, Giacomo Mauro; Perinotti, Paolo [Perimeter Institute for Theoretical Physics, 31 Caroline Street North, Ontario, N2L 2Y5 (Canada); QUIT Group, Dipartimento di Fisica ''A. Volta'' and INFN Sezione di Pavia, via Bassi 6, I-27100 Pavia (Italy)
2011-07-15
We derive quantum theory from purely informational principles. Five elementary axioms - causality, perfect distinguishability, ideal compression, local distinguishability, and pure conditioning - define a broad class of theories of information processing that can be regarded as standard. One postulate - purification - singles out quantum theory within this class.
Derived Categories of Coherent Sheaves
Dmitri Orlov; Alexei Bondal
2002-01-01
We show how derived categories build bridges across the current mathematical mainstream, linking geometric and algebraic, commutative and noncommutative, local and global banks. Arches in these bridges are pieces of semiorthogonal decompositions of triangulated categories. To appear in the Proceedings of the ICM 2002 in Beijing.
Program for IIB Derivative Corrections
Gordon Chalmers
2005-11-05
A Matlab program is presented that computes derivative corrections in the S-dual invariant formulation for IIB graviton scattering to any order in perturbation theory. The coefficients of the four-point function are produced, pertaining to the non-logarithmic terms. The program can be modified to find coefficients of the higher-point functions. Instantons have not explicitly been included.
Derived differential Dominic Joyce, Oxford.
Joyce, Dominic
will describe a new class of geo- metric objects I call d-manifolds -- `derived' smooth manifolds. Some also fit in this framework. 2 #12;All these `invariants' theories have some common features: Â· You manifold of known dimension k. One defines a virtual class [M]vir in Hk(M; Q), which `counts' the points
New hydrophobically modified carboxymethylcellulose derivatives
D. Charpentier; G. Mocanu; A. Carpov; S. Chapelle; L. Merle; G. Müller
1997-01-01
New hydrophobically substituted carboxymethylcellulose derivatives with different percentages of modification by hexadecylamine (from 0.9 to 6% per monomeric unit acid group) were obtained by amidation of the carboxyl group by different methods. The percentage of modification (% HDA) was controlled by conductimetric titration and quantitative 13C NMR spectra on cellulase hydrolyzed oligomers. The least degradation (checked by GPC measurements), was
Phenanthropyran derivatives from Phalaenopsis equestris.
Manako, Y; Wake, H; Tanaka, T; Shimomura, K; Ishimaru, K
2001-10-01
Two phenanthropyran derivatives, 3-methoxy-2,7-dihydroxy-5H-phenanthro[4,5-bcd]pyran and 2,3,7-trihydroxy-5H-phenanthro[4,5-bcd]pyran were isolated from the orchid Phalaenopsis equestri. Their chemical structures were elucidated from spectroscopic (NMR, MS etc.) analyses. PMID:11576607
Alchemical derivatives of reaction energetics
NASA Astrophysics Data System (ADS)
Sheppard, Daniel; Henkelman, Graeme; von Lilienfeld, O. Anatole
2010-08-01
Based on molecular grand canonical ensemble density functional theory, we present a theoretical description of how reaction barriers and enthalpies change as atoms in the system are subjected to alchemical transformations, from one element into another. The change in the energy barrier for the umbrella inversion of ammonia is calculated along an alchemical path in which the molecule is transformed into water, and the change in the enthalpy of protonation for methane is calculated as the molecule is transformed into a neon atom via ammonia, water, and hydrogen fluoride. Alchemical derivatives are calculated analytically from the electrostatic potential in the unperturbed system, and compared to numerical derivatives calculated with finite difference interpolation of the pseudopotentials for the atoms being transformed. Good agreement is found between the analytical and numerical derivatives. Alchemical derivatives are also shown to be predictive for integer changes in atomic numbers for oxygen binding to a 79 atom palladium nanoparticle, illustrating their potential use in gradient-based optimization algorithms for the rational design of catalysts.
Deriving confinement via RG decimations
E. T. Tomboulis
2007-10-10
We present the general framework and building blocks of a recent derivation of the fact that the SU(2) LGT is in a confining phase for all values of the coupling $0 decimations that are shown to constrain the exact partition function and order parameters from above and below, and flow from the weak to the strong coupling regime without encountering a fixed point.
Position Estimation Using Image Derivative
NASA Technical Reports Server (NTRS)
Mortari, Daniele; deDilectis, Francesco; Zanetti, Renato
2015-01-01
This paper describes an image processing algorithm to process Moon and/or Earth images. The theory presented is based on the fact that Moon hard edge points are characterized by the highest values of the image derivative. Outliers are eliminated by two sequential filters. Moon center and radius are then estimated by nonlinear least-squares using circular sigmoid functions. The proposed image processing has been applied and validated using real and synthetic Moon images.
Myeloid-Derived Suppressor Cells
Srinivas Nagaraj; Dmitry I. Gabrilovich
\\u000a The development of tumor-specific T cell tolerance is largely responsible for tumor escape. Accumulation of myeloid-derived\\u000a suppressor cells (MDSCs) in animal tumor models as well as in cancer patients is involved in tumor-associated T cell tolerance.\\u000a In recent years, it has become increasingly evident that MDSCs bring about antigen-specific T cell tolerance by various mechanisms,\\u000a which is the focus of
Iron and iron derived radicals
Borg, D.C.; Schaich, K.M.
1987-04-01
We have discussed some reactions of iron and iron-derived oxygen radicals that may be important in the production or treatment of tissue injury. Our conclusions challenge, to some extent, the usual lines of thought in this field of research. Insofar as they are born out by subsequent developments, the lessons they teach are two: Think fastexclamation Think smallexclamation In other words, think of the many fast reactions that can rapidly alter the production and fate of highly reactive intermediates, and when considering the impact of competitive reactions on such species, think how they affect the microenvironment (on the molecular scale) ''seen'' by each reactive molecule. 21 refs., 3 figs., 1 tab.
Binder enhanced refuse derived fuel
Daugherty, Kenneth E. (Lewisville, TX); Venables, Barney J. (Denton, TX); Ohlsson, Oscar O. (Naperville, IL)
1996-01-01
A refuse derived fuel (RDF) pellet having about 11% or more particulate calcium hydroxide which is utilized in a combustionable mixture. The pellets are used in a particulate fuel bring a mixture of 10% or more, on a heat equivalent basis, of the RDF pellet which contains calcium hydroxide as a binder, with 50% or more, on a heat equivalent basis, of a sulphur containing coal. Combustion of the mixture is effective to produce an effluent gas from the combustion zone having a reduced SO.sub.2 and polycyclic aromatic hydrocarbon content of effluent gas from similar combustion materials not containing the calcium hydroxide.
Myeloid-derived suppressor cells
Chandra, Dinesh; Gravekamp, Claudia
2013-01-01
While conventional anticancer therapies, including surgical resection, radiotherapy, and/or chemotherapy, are relatively efficient at eliminating primary tumors, these treatment modalities are largely ineffective against metastases. At least in part, this reflects the rather inefficient delivery of conventional anticancer agents to metastatic lesions. We have recently demonstrated that myeloid-derived suppressor cells (MDSCs) can be used as cellular missiles to selectively deliver a radioisotope-coupled attenuated variant of Listeria monocytogenes to both primary and metastatic neoplastic lesions in mice with pancreatic cancer. This novel immunotherapeutic intervention robustly inhibited tumor growth while promoting a dramatic decrease in the number of metastases. PMID:24427545
Deriving Laws from Ordering Relations
NASA Technical Reports Server (NTRS)
Knuth, Kevin H.
2004-01-01
The effect of Richard T. Cox's contribution to probability theory was to generalize Boolean implication among logical statements to degrees of implication, which are manipulated using rules derived from consistency with Boolean algebra. These rules are known as the sum rule, the product rule and Bayes Theorem, and the measure resulting from this generalization is probability. In this paper, I will describe how Cox s technique can be further generalized to include other algebras and hence other problems in science and mathematics. The result is a methodology that can be used to generalize an algebra to a calculus by relying on consistency with order theory to derive the laws of the calculus. My goals are to clear up the mysteries as to why the same basic structure found in probability theory appears in other contexts, to better understand the foundations of probability theory, and to extend these ideas to other areas by developing new mathematics and new physics. The relevance of this methodology will be demonstrated using examples from probability theory, number theory, geometry, information theory, and quantum mechanics.
Fourth order spatial derivative gravity
Bemfica, F. S.; Gomes, M. [Instituto de Fisica, Universidade de Sao Paulo Caixa Postal 66318, 05315-970, Sao Paulo, SP (Brazil)
2011-10-15
In this work, we study a modified theory of gravity that contains up to fourth order spatial derivatives as a model for the Horava-Lifshitz gravity. The propagator is evaluated and, as a result, one extra pole is obtained, corresponding to a spin-2 nonrelativistic massless particle, an extra term which jeopardizes renormalizability, besides the unexpected general relativity unmodified propagator. Then unitarity is proved at the tree level, where the general relativity pole has been shown to have no dynamics, remaining only the 2 degrees of freedom of the new pole. Next, the nonrelativistic effective potential is determined from a scattering process of two identical massive gravitationally interacting bosons. In this limit, Newton's potential is obtained, together with a Darwin-like term that comes from the extra nonpole term in the propagator. Regarding renormalizability, this extra term may be harmful by power counting, but it can be eliminated by adjusting the free parameters of the model. This adjustment is in accord with the detailed balance condition suggested in the literature and shows that the way in which extra spatial derivative terms are added is of fundamental importance.
Development of the beta-pressure derivative
Hosseinpour-Zoonozi, Nima
2007-04-25
)/dln(t) derivative) provides an accurate and consistent mechanism for computing the primary pressure derivative (that is the Cartesian derivative, d? p/dt) as well as the "Bourdet" well testing derivative [that is the "semilog" derivative, ? pd(t)=d? p.... 1.3 Statement of the Problem The "Bourdet" well testing pressure derivative function [ref. 1, Bourdet et al] ? pd(t), is known to be a powerful mechanism for well test interpretation ? this is perhaps the most significant single development...
Potential antimalarial derivatives from astraodorol.
Nasomjai, Pitak; Arpha, Kittibhorn; Sodngam, Sirirath; Brandt, Simon D
2014-12-01
Astraodorol, a major lanostane-type triterpene isolated from the edible mushroom Astraeus odoratus, was subjected to chemical modifications. Ten derivatives have been synthesized and their biological activities were evaluated. Compounds 5, 6, 7a, 7c, 7e, 7f, and 7 g exhibited strong antimalarial activity with IC50 values of 4.85, 4.48, 4.16, 4.46, 3.45, 3.23, and 3.41 µg/mL, respectively. Compounds 7a, 7c, and 7e showed moderate cytotoxicity against NCI-H187 with IC50 values of 23.36, 34.28, and 9.84 µg/mL. Compound 7e demonstrated moderate cytotoxicity against KB, MCF-7, and Vero cell lines with IC50 values of 16.94, 49.60, and 26.48 µg/mL, respectively. PMID:24748514
Deriving Laws from Ordering Relations
NASA Technical Reports Server (NTRS)
Knuth, Kevin H.
2003-01-01
It took much effort in the early days of non-Euclidean geometry to break away from the mindset that all spaces are flat and that two distinct parallel lines do not cross. Up to that point, all that was known was Euclidean geometry, and it was difficult to imagine anything else. We have suffered a similar handicap brought on by the enormous relevance of Boolean algebra to the problems of our age-logic and set theory. Previously, I demonstrated that the algebra of questions is not Boolean, but rather is described by the free distributive algebra. To get to this stage took much effort, as many obstacles-most self-placed-had to be overcome. As Boolean algebras were all I had ever known, it was almost impossible for me to imagine working with an algebra where elements do not have complements. With this realization, it became very clear that the sum and product rules of probability theory at the most basic level had absolutely nothing to do with the Boolean algebra of logical statements. Instead, a measure of degree of inclusion can be invented for many different partially ordered sets, and the sum and product rules fall out of the associativity and distributivity of the algebra. To reinforce this very important idea, this paper will go over how these constructions are made, while focusing on the underlying assumptions. I will derive the sum and product rules for a distributive lattice in general and demonstrate how this leads to probability theory on the Boolean lattice and is related to the calculus of quantum mechanical amplitudes on the partially ordered set of experimental setups. I will also discuss the rules that can be derived from modular lattices and their relevance to the cross-ratio of projective geometry.
A study on real estate derivatives
Lim, Jong Yoon, S.M. Massachusetts Institute of Technology
2006-01-01
All major asset classes including stocks and bonds have a well developed derivative market. Derivatives enable counterparties to reflect a view on a particular market, without having to trade the underlying asset. This ...
Deriving Ephemeral Authentication Using Channel Axioms
Sheldon, Nathan D.
Deriving Ephemeral Authentication Using Channel Axioms Dusko Pavlovic1 and Catherine Meadows2 1 of Mathematics/ISG. #12;Deriving Ephemeral Authentication Using Channel Axioms 239 of the information sent along
Derivative Sign Patterns in Two Dimensions
ERIC Educational Resources Information Center
Schilling, Kenneth
2013-01-01
Given a function defined on a subset of the plane whose partial derivatives never change sign, the signs of the partial derivatives form a two-dimensional pattern. We explore what patterns are possible for various planar domains.
17 CFR 200.506 - Derivative classification.
Code of Federal Regulations, 2011 CFR
2011-04-01
...Exchanges 2 2011-04-01 2011-04-01 false Derivative classification. 200.506 Section 200.506 Commodity...National Security Information and Material § 200.506 Derivative classification. Any document that includes...
5 CFR 2500.5 - Derivative classification.
Code of Federal Regulations, 2011 CFR
2011-01-01
...Personnel 3 2011-01-01 2011-01-01 false Derivative classification. 2500.5 Section 2500.5 Administrative...PRESIDENT INFORMATION SECURITY REGULATION § 2500.5 Derivative classification. The Office of Administration serves...
5 CFR 2500.5 - Derivative classification.
Code of Federal Regulations, 2010 CFR
2010-01-01
...Personnel 3 2010-01-01 2010-01-01 false Derivative classification. 2500.5 Section 2500.5 Administrative...PRESIDENT INFORMATION SECURITY REGULATION § 2500.5 Derivative classification. The Office of Administration serves...
17 CFR 200.506 - Derivative classification.
Code of Federal Regulations, 2010 CFR
2010-04-01
...Exchanges 2 2010-04-01 2010-04-01 false Derivative classification. 200.506 Section 200.506 Commodity...National Security Information and Material § 200.506 Derivative classification. Any document that includes...
Code of Federal Regulations, 2014 CFR
2014-07-01
...aminonaphthalenesulfonic acid derivative, ammonium salt (generic). 721.10039 Section 721...aminonaphthalenesulfonic acid derivative, ammonium salt (generic). (a) Chemical substance...aminonaphthalenesulfonic acid derivative, ammonium salt (PMN P-02-514) is subject to...
Code of Federal Regulations, 2013 CFR
2013-07-01
...aminonaphthalenesulfonic acid derivative, ammonium salt (generic). 721.10039 Section 721...aminonaphthalenesulfonic acid derivative, ammonium salt (generic). (a) Chemical substance...aminonaphthalenesulfonic acid derivative, ammonium salt (PMN P-02-514) is subject to...
Code of Federal Regulations, 2011 CFR
2011-07-01
...aminonaphthalenesulfonic acid derivative, ammonium salt (generic). 721.10039 Section 721...aminonaphthalenesulfonic acid derivative, ammonium salt (generic). (a) Chemical substance...aminonaphthalenesulfonic acid derivative, ammonium salt (PMN P-02-514) is subject to...
Tümer, Yasemin; Koç, L Yasemin; Asmafiliz, Nuran; K?l?ç, Zeynel; Hökelek, Tuncer; Soltanzade, Hossien; Aç?k, Leyla; Yola, Mehmet Lütfi; Solak, Ali Osman
2015-01-01
The gradual Cl replacement reactions of NN (1-3) or NO spirocyclic monoferrocenyl cyclotriphosphazenes (4 and 5) with the potassium salt of 4-hydroxy-3-methoxybenzaldehyde (potassium vanillinate) resulted in the mono (1a-5a), geminal (gem-1b-5b), non-geminal (cis-5b and trans -1b-4b), tri (1c, 3c-5c) and tetra-vanillinato-substituted phosphazenes (1d-5d). All the phosphazene derivatives have stereogenic P-center(s), except tetra-substituted ones. The vanillinatophosphazenes have reversible voltammograms with one-electron anodic and cathodic peaks which are attributed to ferrocenyl redox probe. The structures of the new phosphazene compounds were determined by FTIR, MS, (1)H, (13)C{(1)H} and (31)P{(1)H} NMR spectral data. The solid-state structure of cis -5b was examined by single-crystal X-ray diffraction techniques. In addition, the compounds were tested in HeLa cancer cell lines using MTT assay. The 12 phosphazene derivatives were screened for antimicrobial activity, and 3c was very effective against S. aureus even at 4.88 µM concentration, taking into account the MIC values. Besides, interactions between the phosphazenes and pBR322 plasmid DNA were also investigated. PMID:25491284
Stability derivatives of cones at supersonic speeds
NASA Technical Reports Server (NTRS)
Tobak, Murry; Wehrend, William R
1956-01-01
The aerodynamic stability derivatives due to pitching velocity and vertical acceleration are derived for circular cones traveling at supersonic speeds. Both first-order and a combination of first and second order potential solutions are obtained, and in calculations for the forces, no approximations are made to the tangency condition or the isentropic pressure relation. In addition, expressions for the forces, moments, and stability derivatives of arbitrary bodies of revolution are derived from Newtonian impact theory.
Derived categories and their uses Bernhard Keller
Keller, Bernhard - Institut de MathÃ©matiques de Jussieu, UniversitÃ© Paris 7
1.1 Historical remarks Derived categories are a `formalism for hyperhomology' [61]. Used at first. Kashiwara [37]* *. Derived categories have now become the standard language of microlocal analysis (cf. [38 and Bernstein-Gelfand use* *d derived categories to establish a beautiful relation between coherent sheaves
Postgraduate Scholarship Pricing temperature derivatives and modelling
Banaji,. Murad
the volumetric risk of the energy units sold, rather than the price risk of each unit. Weather derivativesPostgraduate Scholarship Pricing temperature derivatives and modelling the market price of risk: Pricing temperature derivatives and modelling the market price of risk. Main Supervisor: A. Alexandridis
Improved Second Derivative Test for Relative Extrema
ERIC Educational Resources Information Center
Wu, Yan
2007-01-01
In this note, a modified Second Derivative Test is introduced for the relative extrema of a single variable function. This improved test overcomes the difficulty of the second derivative vanishing at the critical point, while in contrast the traditional test fails for this case. A proof for this improved Second Derivative Test is presented,…
The Fourth Partial Derivative In Transport Dynamics
Trinh Khanh Tuoc
2010-01-11
A new fourth partial derivative is introduced for the study of transport dynamics. It is a Lagrangian partial derivative following the path of diffusion, not the path of convection. Use of this derivative decouples the effect of diffusion and convection and simplifies the analysis of transport processes.
Structural design utilizing updated, approximate sensitivity derivatives
NASA Technical Reports Server (NTRS)
Scotti, Stephen J.
1993-01-01
A method to improve the computational efficiency of structural optimization algorithms is investigated. In this method, the calculations of 'exact' sensitivity derivatives of constraint functions are performed only at selected iterations during the optimization process. The sensitivity derivatives utilized within other iterations are approximate derivatives which are calculated using an inexpensive derivative update formula. Optimization results are presented for an analytic optimization problem (i.e., one having simple polynomial expressions for the objective and constraint functions) and for two structural optimization problems. The structural optimization results indicate that up to a factor of three improvement in computation time is possible when using the updated sensitivity derivatives.
STS Derived Exploration Launch Operations
NASA Technical Reports Server (NTRS)
Best, Joel; Sorge, L.; Siders, J.; Sias, Dave
2004-01-01
A key aspect of the new space exploration programs will be the approach to optimize launch operations. A STS Derived Launch Vehicle (SDLV) Program can provide a cost effective, low risk, and logical step to launch all of the elements of the exploration program. Many benefits can be gained by utilizing the synergy of a common launch site as an exploration spaceport as well as evolving the resources of the current Space Shuttle Program (SSP) to meet the challenges of the Vision for Space Exploration. In particular, the launch operation resources of the SSP can be transitioned to the exploration program and combined with the operations efficiencies of unmanned EELVs to obtain the best of both worlds, resulting in lean launch operations for crew and cargo missions of the exploration program. The SDLV Program would then not only capture the extensive human space flight launch operations knowledge, but also provide for the safe fly-out of the SSP through continuity of system critical skills, manufacturing infrastructure, and ability to maintain and attract critical skill personnel. Thus, a SDLV Program can smoothly transition resources from the SSP and meet the transportation needs to continue the voyage of discovery of the space exploration program.
NASA Technical Reports Server (NTRS)
1982-01-01
The QuadraScan Longterm Flow Monitoring System is a second generation sewer monitor developed by American Digital Systems, Inc.'s founder Peter Petroff. Petroff, a former spacecraft instrumentation designer at Marshall Space Flight Center, used expertise based on principles acquired in Apollo and other NASA programs. QuadraScan borrows even more heavily from space technology, for example in its data acquisition and memory system derived from NASA satellites. "One-time" measurements are often plagued with substantial errors due to the flow of groundwater absorbed into the system. These system sizing errors stem from a basic informational deficiency: accurate, reliable data on how much water flows through a sewer system over a long period of time is very difficult to obtain. City officials are turning to "permanent," or long-term sewer monitoring systems. QuadraScan offers many advantages to city officials such as the early warning capability to effectively plan for city growth in order to avoid the crippling economic impact of bans on new sewer connections in effect in many cities today.
Animal-derived pharmaceutical proteins.
Redwan, el-Rashdy M
2009-01-01
Livestock animals have made a significant contribution to human health and well-being throughout humankind's history. A significant contribution of farm animals to human health are the longstanding use of bovine and porcine for production of insulin (for treatment of diabetes), gelatin (for pharmaceutical and other purposes), as well as horse and sheep antibody against natural venoms, toxins, drugs and microbial peptides. Gelatin being the biggest animal protein consumed in human health, follows with antibodies fragments. The chronic problem of animal-derived therapeutics, especially those of high molecular weight, is the immunogenicity induction in addition to their biosafety. However, the invertebrates and lower vertebrates donate the human being a several crucial emergency saving life small-peptides or their analogs such as Refludan, Prialt, Exendin. Not only, but the farm animals are enormously using as models for novel surgical strategies, testing of biodegradable implants and sources of tissue replacements, such as skin and heart valves. Recently, they are being harnessing as bioreactor for production of biopharmaceutical related products through gene farming with efficiency far greater than any conventional microbial or cell-culture production systems. Only 16 transgenic cows would be covering the worldwide needs from human growth hormone. The transgenic, especially animal, technology would be solving a several biopharmaceutical products disadvantages, such as cost, biosafety, immunogenicity and the availability dimensions. PMID:19591041
Unconventional fuel: Tire derived fuel
Hope, M.W. [Waste Recovery, Inc., Portland, OR (United States)
1995-09-01
Material recovery of scrap tires for their fuel value has moved from a pioneering concept in the early 1980`s to a proven and continuous use in the United States` pulp and paper, utility, industrial, and cement industry. Pulp and paper`s use of tire derived fuel (TDF) is currently consuming tires at the rate of 35 million passenger tire equivalents (PTEs) per year. Twenty mills are known to be burning TDF on a continuous basis. The utility industry is currently consuming tires at the rate of 48 million PTEs per year. Thirteen utilities are known to be burning TDF on a continuous basis. The cement industry is currently consuming tires at the rate of 28 million PTEs per year. Twenty two cement plants are known to be burning TDF on a continuous basis. Other industrial boilers are currently consuming tires at the rate of 6.5 million PTEs per year. Four industrial boilers are known to be burning TDF on a continuous basis. In total, 59 facilities are currently burning over 117 million PTEs per year. Although 93% of these facilities were not engineered to burn TDF, it has become clear that TDF has found acceptance as a supplemental fuel when blending with conventional fuels in existing combustion devices designed for normal operating conditions. The issues of TDF as a supplemental fuel and its proper specifications are critical to the successful development of this fuel alternative. This paper will focus primarily on TDF`s use in a boiler type unit.
?-Nitro Derivatives of Iron Corrolates
Nardis, Sara; Stefanelli, Manuela; Mohite, Pruthviraj; Pomarico, Giuseppe; Tortora, Luca; Manowong, Machima; Chen, Ping; Fronczek, Frank R.; McCandless, Gregory T.
2012-01-01
Two different methods for the regioselective nitration of different meso-triarylcorroles leading to the corresponding ?-substituted nitrocorrole iron complexes have been developed. A two-step procedure affords three Fe(III) nitrosyl products - the unsubstituted corrole, the 3-nitrocorrole and the 3,17-dinitrocorrole. In contrast, a one-pot synthetic approach drives the reaction almost exclusively to formation of the iron nitrosyl 3,17-dinitrocorrole. Electron-releasing substituents on the meso-aryl groups of the triarylcorroles induce higher yields and longer reaction times than what is observed for the synthesis of similar triarylcorroles with electron-withdrawing functionalities, and these results can be confidently attributed to the facile formation and stabilization of an intermediate iron corrole ?-cation radical. Electron-withdrawing substituents on the meso-aryl groups of triarylcorrole also seem to labilize the axial nitrosyl group which, in the case of the pentafluorophenylcorrole derivative, results in the direct formation of a disubstituted iron ?-oxo dimer complex. The influence of meso-aryl substituents on the progress and products of the nitration reaction was investigated. In addition, to elucidate the most important factors which influence the redox reactivity of these different iron nitrosyl complexes, selected compounds were examined by cyclic voltammetry and thin-layer UV-visible or FTIR spectroelectrochemistry in CH2Cl2. PMID:22394192
Satellite-Derived Management Zones
NASA Technical Reports Server (NTRS)
Lepoutre, Damien; Layrol, Laurent
2005-01-01
The term "satellite-derived management zones" (SAMZ) denotes agricultural management zones that are subdivisions of large fields and that are derived from images of the fields acquired by instruments aboard Earth-orbiting satellites during approximately the past 15 years. "SAMZ" also denotes the methodology and the software that implements the methodology for creating such zones. The SAMZ approach is one of several products of continuing efforts to realize a concept of precision agriculture, which involves optimal variations in seeding, in application of chemicals, and in irrigation, plus decisions to farm or not to farm certain portions of fields, all in an effort to maximize profitability in view of spatial and temporal variations in the growth and health of crops, and in the chemical and physical conditions of soils. As used here, "management zone" signifies, more precisely, a subdivision of a field within which the crop-production behavior is regarded as homogeneous. From the perspective of precision agriculture, management zones are the smallest subdivisions between which the seeding, application of chemicals, and other management parameters are to be varied. In the SAMZ approach, the main sources of data are the archives of satellite imagery that have been collected over the years for diverse purposes. One of the main advantages afforded by the SAMZ approach is that the data in these archives can be reused for purposes of precision agriculture at low cost. De facto, these archives contain information on all sources of variability within a field, including weather, crop types, crop management, soil types, and water drainage patterns. The SAMZ methodology involves the establishment of a Web-based interface based on an algorithm that generates management zones automatically and quickly from archival satellite image data in response to requests from farmers. A farmer can make a request by either uploading data describing a field boundary to the Web site or else drawing the boundary on a reference image. Hence, a farmer can start to engage in precision farming shortly after gaining access to the Web site, without the need for incurring the high costs of conventional precision-agriculture data-collection practices that include collecting soil samples, mapping electrical conductivity of soil, and compiling multiyear crop-yield data. Given the boundary of a field, a SAMZ server computes the zones within the field in a three-stage process. In the first stage, a vector-valued image of the field is constructed by assembling, from the archives, the equivalent of a stack of the available images of the field (see figure). In the second stage, the vector-valued image is analyzed by use of a wavelet transform that detects spatial variations considered significant for precision farming while suppressing small-scale heterogeneities that are regarded as insignificant. In the third stage, a segmentation algorithm assembles the zones from smaller regions that have been identified in the wavelet analysis.
Derivation of quantum theories symmetries and the exact solution of the derived system
Khorrami, M; Alimohammadi, M
1996-01-01
Based on the technique of derivation of a theory, presented in our recent paper, we investigate the properties of the derived quantum system. We show that the derived quantum system possesses the (nonanomalous) symmetries of the original one, and prove that the exact Green functions of the derived theory are expressed in terms of the semiclassically approximated Green functions of the original theory.
Rommens, Caius M.; Bougri, Oleg; Yan, Hua; Humara, Jaime M.; Owen, Joanna; Swords, Kathy; Ye, Jingsong
2005-01-01
The transfer of DNA from Agrobacterium to plant cell nuclei is initiated by a cleavage reaction within the 25-bp right border of Ti plasmids. In an effort to develop all-native DNA transformation vectors, 50 putative right border alternatives were identified in both plant expressed sequence tags and genomic DNA. Efficacy tests in a tobacco (Nicotiana tabacum) model system demonstrated that 14 of these elements displayed at least 50% of the activity of conventional Agrobacterium transfer DNA borders. Four of the most effective plant-derived right border alternatives were found to be associated with intron-exon junctions. Additional elements were embedded within introns, exons, untranslated trailers, and intergenic DNA. Based on the identification of a single right border alternative in Arabidopsis and three in rice (Oryza sativa), the occurrence of this motif was estimated at a frequency of at least 0.8×10?8. Modification of plasmid DNA sequences flanking the alternative borders demonstrated that both upstream and downstream sequences play an important role in initiating DNA transfer. Optimal DNA transfer required the elements to be preceded by pyrimidine residues interspaced by AC-rich trinucleotides. Alteration of this organization lowered transformation frequencies by 46% to 93%. Despite their weaker resemblance with left borders, right border alternatives also functioned effectively in terminating DNA transfer, if both associated with an upstream A[C/T]T[C/G]A[A/T]T[G/T][C/T][G/T][C/G]A[C/T][C/T][A/T] domain and tightly linked cytosine clusters at their junctions with downstream DNA. New insights in border region requirements were used to construct an all-native alfalfa (Medicago sativa) transfer DNA vector that can be used for the production of intragenic plants. PMID:16244143
Drug laws and the 'derivative' problem.
King, Leslie A; Ujváry, István; Brandt, Simon D
2014-01-01
The concept of a 'derivative' is used widely in chemistry, where its precise meaning depends on the circumstances. However, numerous examples of derivative also occur in domestic drugs legislation, some of which stem from the 1961 United Nations Single Convention on Narcotic Drugs. There is a commonly held view that only 'first-order' derivatives should be considered: substances that can be created from a parent structure in a single chemical reaction. In other words, 'derivatives of derivatives' are excluded. However, some substances related to ecgonine (e.g. 2-carbomethoxytropinone) are clearly convertible to cocaine, even though this may require more than one reaction step. It follows that 2-carbomethoxytropinone is a controlled drug, a situation that most chemists would regard as perverse. A more extreme example of the complexity of 'derivative' is shown by the conversion of thebaine to buprenorphine. Even though this requires six or more stages, the US Drug Enforcement Administration successfully argued in a 1986 case that for the purposes of the Controlled Substances Act, the number of steps required was irrelevant; buprenorphine was a derivative of thebaine. Because the term derivative is rarely defined in statutes, the legal status of some substances, such as 2-bromo-LSD, is uncertain. Although a number of definitions of derivative can be found in the chemical literature, no single definition is adequate to describe all situations where it occurs in legislation. Unless qualified, it is suggested that the term derivative should be avoided in any future legislation. PMID:23949903
Drug Nanoparticle Formulation Using Ascorbic Acid Derivatives
Moribe, Kunikazu; Limwikrant, Waree; Higashi, Kenjirou; Yamamoto, Keiji
2011-01-01
Drug nanoparticle formulation using ascorbic acid derivatives and its therapeutic uses have recently been introduced. Hydrophilic ascorbic acid derivatives such as ascorbyl glycoside have been used not only as antioxidants but also as food and pharmaceutical excipients. In addition to drug solubilization, drug nanoparticle formation was observed using ascorbyl glycoside. Hydrophobic ascorbic acid derivatives such as ascorbyl mono- and di-n-alkyl fatty acid derivatives are used either as drugs or carrier components. Ascorbyl n-alkyl fatty acid derivatives have been formulated as antioxidants or anticancer drugs for nanoparticle formulations such as micelles, microemulsions, and liposomes. ASC-P vesicles called aspasomes are submicron-sized particles that can encapsulate hydrophilic drugs. Several transdermal and injectable formulations of ascorbyl n-alkyl fatty acid derivatives were used, including ascorbyl palmitate. PMID:21603195
Consistent pseudo-derivatives in meshless methods
Y. Krongauz; T. Belytschko
1997-01-01
A meshless Petrov-Galerkin formulation is developed in which derivatives of the trial functions are obtained as a linear combination of derivatives of Shepard functions. A key contribution is the development of conditions on test functions and trial functions for nonintegrable pseudo-derivatives for Petrov-Galerkin method which pass the patch test. Numerical results show that the resulting method is substantially more accurate
Extending Bauer's corollary to fractional derivatives
David W. Dreisigmeyer; Peter M. Young
2004-02-11
We comment on the method of Dreisigmeyer and Young [D. W. Dreisigmeyer and P. M. Young, J. Phys. A \\textbf{36}, 8297, (2003)] to model nonconservative systems with fractional derivatives. It was previously hoped that using fractional derivatives in an action would allow us to derive a single retarded equation of motion using a variational principle. It is proven that, under certain reasonable assumptions, the method of Dreisigmeyer and Young fails.
Missile motion sensitivity to dynamic stability derivatives
NASA Astrophysics Data System (ADS)
Langham, T. F.
1980-09-01
A dynamic derivative sensitivity study was conducted to demonstrate the importance of dynamic derivatives in missile motion simulation studies. Generalized bank-to-turn and yaw-to-turn missile configurations were used with a six degree of freedom linearized stability program. The effects of various dynamic derivatives on missile stability were investigated in both level and turning flight for several Mach numbers and altitude conditions.
Proceedings of refuse-derived fuel (RDF)
Saltiel, C. (Florida Univ., Gainesville, FL (United States))
1991-01-01
This book contains proceedings of Refuse-Derived Fuel (RDF)-Quality. Standards and Processing. Topics covered include: An Overview of RDF Processing Systems: Current Status, Design Features, and Future Trends. The Impact of Recycling and Pre-Combustion Processing of Municipal Solid Waste on Fuel Properties and Steam Combustion. The Changing Role of Standards in the Marketing of RDF. Refuse Derived Fuel Quality Requirements for Firing in Utility, Industrial or Dedicated Boilers. Refuse-Derived Fuel Moisture Effects on Boiler Performance and Operability. Refuse Derived Fuels: Technology, Processing, Quality and Combustion Experiences.
Anisotropic higher derivative gravity and inflationary universe
W. F. Kao
2006-05-21
Stability analysis of the Kantowski-Sachs type universe in pure higher derivative gravity theory is studied in details. The non-redundant generalized Friedmann equation of the system is derived by introducing a reduced one dimensional generalized KS type action. This method greatly reduces the labor in deriving field equations of any complicate models. Existence and stability of inflationary solution in the presence of higher derivative terms are also studied in details. Implications to the choice of physical theories are discussed in details in this paper.
Mantle derived economic sulfide mineralization?
NASA Astrophysics Data System (ADS)
Krivolutskaya, Nadezda; Gongalskiy, Bronislav; Svirskaya, Natalia
2014-05-01
Sulfide ores of the unique Pt-Cu-Ni Noril'sk deposits are characterized by heavy sulfur isotopic composition (d34S = 6-18 ‰ ; Grinenko, 1985). These data are traditionally explained by the crustal contamination of the mantle melts by Devonian sedimentary rocks with anhydrites at certain depths or in a chamber of crystallization (Naldrett, 1992; Li et al., 2009). However, data on the distribution of major and trace elements and isotopic composition (their eNd, 87Sr/86Sr, d34S) in the contact zones of the intrusions with the host rocks are at variance with any significant in-situ contamination. Moreover , the mechanism of the "digestion" of this high-temperature material (Tm = 1430ºC) by the lower temperature magma (1250ºC) has never been analyzed and questioned. Our pioneering data on the sulfur radiogenic isotopes in the anhydrite are in conflict with the hypothesis that this mineral could serve as a sulfur source for the Noril'sk ores. The fact that the average composition of the intrusions is independent on the stratigraphic setting of these intrusions, which can be hosted by limestone, sandstone, and/or basalt, provides further support for the idea that no assimilation took place at the depths of the chambers in which the melts crystallized.The reason for the heavy sulfur isotopic composition of ores in the Noril'sk district is still uncertain. Last data obtained on the sulfur isotopic composition of basalts and ores from some intrusions in the Taimyr Peninsula likely provide a clue to this problem. The highest d34S values in rocks of all of the trap formations were detected in the Gudchikhinsky picrites (d34S = +8,7; Ripley et al., 2003) formed from a primitive mantle magma. They are geochemically similar to the rocks from the Dyumtaleysky Massif (d34S = 12.2; Krivolutskaya and Gongalsky, 2013) which crystallized from a primitive mantle-derived magma (with no Ta-Nb and Pb anomalies and high Gd/Yb ratio) too. This intrusion comprises economic important sulfide ores with geochemical and mineralogical characteristics similar to unique Noril'sk deposits - Talnakh, Okty'abr sky and Norilsk 1. The features of the Dyumtaleysky massif can be explained by its origin from an unusual sulfide-bearing mantle source that had sulfides through earlier crustal-mantle interaction. These data support that the mantle source of magmas in the Noril'sk district was enriched in the heavy sulfur isotope. It is the age difference that could be responsible for the unusual composition of the Noril'sk ores, because the mantle source in the Early Mesozoic was remarkably different from that in the Proterozoic one, when practically all Cu-Ni deposits worldwide were produced.
75 FR 63113 - Financial Resources Requirements for Derivatives Clearing Organizations
Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-14
...Financial Resources Requirements for Derivatives Clearing Organizations AGENCY: Commodity...financial resources requirements for derivatives clearing organizations (DCOs) for...execution requirements on standardized derivative products; (3) creating...
Analysis of Blackbody Radiation with Derivative Spectroscopy.
ERIC Educational Resources Information Center
Dusek, J.; And Others
1980-01-01
Describes an undergraduate experiment which uses derivative spectroscopy to investigate the validity of the Planck function appearing in the blackbody radiation law. These measurements allow a critical examination of this function and also serve as an introduction to derivative spectroscopy techniques. (Author/HM)
Derived categories and their uses Bernhard Keller
Keller, Bernhard - Institut de MathÃ©matiques de Jussieu, UniversitÃ© Paris 7
UniversitÂ´e Paris 7 75251 Paris Cedex 05 France keller@mathp7.jussieu.fr #12;1 Introduction 1.1 Historical differential equations by M. Sato [53] and M. Kashiwara [37]. Derived categories have now become the standard] and [3], Beilinson and Bernstein-Gelfand used derived categories to establish a beautiful relation
Derived categories and their uses Bernhard Keller
Keller, Bernhard - Institut de MathÃ©matiques de Jussieu, UniversitÃ© Paris 7
Universit'e Paris 7 75251 Paris Cedex 05 France keller@mathp7.jussieu.fr #12; 1 Introduction 1.1 Historical differential equations by M. Sato [53] and M. Kashiwara [37]. Derived categories have now become the standard] and [3], Beilinson and BernsteinÂGelfand used derived categories to establish a beautiful relation
Aging and rejuvenation with fractional derivatives
NASA Astrophysics Data System (ADS)
Aquino, Gerardo; Bologna, Mauro; Grigolini, Paolo; West, Bruce J.
2004-09-01
We discuss a dynamic procedure that makes fractional derivatives emerge in the time asymptotic limit of non-Poisson processes. We find that two-state fluctuations, with an inverse power-law distribution of waiting times, finite first moment, and divergent second moment, namely, with the power index ? in the interval 2derivative term. We show that the order of the fractional derivative depends on the age of the process under study. If the system is infinitely old, the order of the fractional derivative, o , is given by o=3-? . A brand new system is characterized by the degree o=?-2 . If the system is prepared at time -ta<0 and the observation begins at time t=0 , we derive the following scenario. For times 0
Biology-Derived Algorithms in Engineering Optimization
Yang, Xin-She
2010-01-01
Biology-derived algorithms are an important part of computational sciences, which are essential to many scientific disciplines and engineering applications. Many computational methods are derived from or based on the analogy to natural evolution and biological activities, and these biologically inspired computations include genetic algorithms, neural networks, cellular automata, and other algorithms.
Cluster algebras and derived categories Bernhard Keller
Keller, Bernhard - Institut de Mathématiques de Jussieu, Université Paris 7
Cluster algebras and derived categories Bernhard Keller Abstract. This is an introductory survey on cluster algebras and their (additive) cat- egorification using derived categories of Ginzburg algebras. After a gentle introduction to cluster combinatorics, we review important examples of coordinate rings
Optimal Derivative Strategies with Discrete Rebalancing
Nicole Branger; Beate Breuer; Christian Schlag
2008-01-01
Optimal asset allocation strategies are often derived in continuous time models, but have to be implemented in discrete time. It has been shown that in models with stochastic volatility or jumps, an investor who just uses the continuous time strategy in discrete time has to trade at least daily to profit from having access to derivatives. In this paper, we
UNIVERSITY OF SOUTH FLORIDA DERIVATIVES POLICY
Meyers, Steven D.
risks by managing the asset-liability structure of the University, identifying responsible parties. The Policy requires the recognition of all derivatives as either assets or liabilities in the statement for the University for the management of corporate risk associated with derivative instruments and hedging activities
Branching problems of Zuckerman derived functor modules
Kobayashi, Toshiyuki
Branching problems of Zuckerman derived functor modules Dedicated to Gregg Zuckerman subgroups. Highlighting the case where the un- derlying (g, K)-modules of are isomorphic to Zuckerman, Zuckerman derived functor module, unitary representation, multiplicity-free representation 2010 MSC: Primary
Derivational Morphology and Base Morpheme Frequency
ERIC Educational Resources Information Center
Ford, M. A.; Davis, M. H.; Marslen-Wilson, W. D.
2010-01-01
Morpheme frequency effects for derived words (e.g. an influence of the frequency of the base "dark" on responses to "darkness") have been interpreted as evidence of morphemic representation. However, it has been suggested that most derived words would not show these effects if family size (a type frequency count claimed to reflect semantic…
Few Fractional Order Derivatives and Their Computations
ERIC Educational Resources Information Center
Bhatta, D. D.
2007-01-01
This work presents an introductory development of fractional order derivatives and their computations. Historical development of fractional calculus is discussed. This paper presents how to obtain computational results of fractional order derivatives for some elementary functions. Computational results are illustrated in tabular and graphical…
Tilt/Integral/Derivative Compensators For Controllers
NASA Technical Reports Server (NTRS)
Lurie, Boris J.
1995-01-01
Tilt/integral/derivative (TID) compensators for tunable feedback control systems offer advantages over proportional/integral/derivative compensators. Designed and adjusted more easily, and made to reject disturbances more strongly and less sensitive to variations in parameters of controlled system.
Understanding the Derivative through the Calculus Triangle
ERIC Educational Resources Information Center
Weber, Eric; Tallman, Michael; Byerley, Cameron; Thompson, Patrick W.
2012-01-01
Typical treatments of the derivative do not clearly convey the idea that the derivative function represents the original function's rate of change. Revealing the relationship between a function and its rate-of-change function for static values of "x" does not facilitate productive ways of thinking about generating the rate-of-change function or…
Can material time derivative be objective?
T. Matolcsi; P. Van
2005-10-10
The concept of objectivity in classical field theories is traditionally based on time dependent Euclidean transformations. In this paper we treat objectivity in a four-dimensional setting, calculate Christoffel symbols of the spacetime transformations, and give covariant and material time derivatives. The usual objective time derivatives are investigated.
Smoothing splines: Regression, derivatives and deconvolution
NASA Technical Reports Server (NTRS)
Rice, J.; Rosenblatt, M.
1982-01-01
The statistical properties of a cubic smoothing spline and its derivative are analyzed. It is shown that unless unnatural boundary conditions hold, the integrated squared bias is dominated by local effects near the boundary. Similar effects are shown to occur in the regularized solution of a translation-kernel intergral equation. These results are derived by developing a Fourier representation for a smoothing spline.
I??klan, Muhammet; Sonkaya, Ömer; Hökelek, Tuncer
2013-01-01
In the title spiro-phosphazene derivative, C33H46N9OP3, the phosphazene and six-membered N/O rings are in flattened chair and twisted-boat conformations, respectively. The naphthalene ring system and the pyridine ring are oriented at a dihedral angle of 41.82?(4)°. In the crystal, weak C—H?O hydrogen bonds link the molecules related by translation along the a axis into chains. C—H?? interactions aggregate these chains into layers parallel to the ab plane. PMID:23795145
I??klan, Muhammet; Sonkaya, Omer; Hökelek, Tuncer
2013-06-01
In the title spiro-phosphazene derivative, C33H46N9OP3, the phosphazene and six-membered N/O rings are in flattened chair and twisted-boat conformations, respectively. The naphthalene ring system and the pyridine ring are oriented at a dihedral angle of 41.82?(4)°. In the crystal, weak C-H?O hydrogen bonds link the mol-ecules related by translation along the a axis into chains. C-H?? inter-actions aggregate these chains into layers parallel to the ab plane. PMID:23795145
17 CFR 200.507 - Declassification dates on derivative documents.
Code of Federal Regulations, 2011 CFR
2011-04-01
... false Declassification dates on derivative documents. 200.507 Section 200...200.507 Declassification dates on derivative documents. (a) A document...need for classification. (b) A derivative document that derives its...
17 CFR 200.507 - Declassification dates on derivative documents.
Code of Federal Regulations, 2013 CFR
2013-04-01
... false Declassification dates on derivative documents. 200.507 Section 200...200.507 Declassification dates on derivative documents. (a) A document...need for classification. (b) A derivative document that derives its...
17 CFR 200.507 - Declassification dates on derivative documents.
Code of Federal Regulations, 2012 CFR
2012-04-01
... false Declassification dates on derivative documents. 200.507 Section 200...200.507 Declassification dates on derivative documents. (a) A document...need for classification. (b) A derivative document that derives its...
17 CFR 200.507 - Declassification dates on derivative documents.
Code of Federal Regulations, 2010 CFR
2010-04-01
... false Declassification dates on derivative documents. 200.507 Section 200...200.507 Declassification dates on derivative documents. (a) A document...need for classification. (b) A derivative document that derives its...
Risk management, derivatives and shariah compliance
NASA Astrophysics Data System (ADS)
Bacha, Obiyathulla Ismath
2013-04-01
Despite the impressive growth of Islamic Banking and Finance (IBF), a number of weaknesses remain. The most important of this is perhaps the lack of shariah compliant risk management tools. While the risk sharing philosophy of Islamic Finance requires the acceptance of risk to justify returns, the shariah also requires adherents to avoid unnecessary risk-maysir. The requirement to avoid maysir is in essence a call for the prudent management of risk. Contemporary risk management revolves around financial engineering, the building blocks of which are financial derivatives. Despite the proven efficacy of derivatives in the management of risk in the conventional space, shariah scholars appear to be suspicious and uneasy with their use in IBF. Some have imposed outright prohibition of their use. This paper re-examines the issue of contemporary derivative instruments and shariah compliance. The shariah compatibility of derivatives is shown in a number of ways. First, by way of qualitative evaluation of whether derivatives can be made to comply with the key prohibitions of the sharia. Second, by way of comparing the payoff profiles of derivatives with risk sharing finance and Bai Salam contracts. Finally, the equivalence between shariah compliant derivatives like the IPRS and Islamic FX Currency Forwards with conventional ones is presented.
Theory of Financial Risk and Derivative Pricing
NASA Astrophysics Data System (ADS)
Bouchaud, Jean-Philippe; Potters, Marc
2004-02-01
Summarizing market data developments, some inspired by statistical physics, this book explains how to better predict the actual behavior of financial markets with respect to asset allocation, derivative pricing and hedging, and risk control. Risk control and derivative pricing are major concerns to financial institutions. The need for adequate statistical tools to measure and anticipate amplitude of potential moves of financial markets is clearly expressed, in particular for derivative markets. Classical theories, however, are based on assumptions leading to systematic (sometimes dramatic) underestimation of risks. First edition Hb (2000): 0-521-78232-5
A direct derivative MC-SCF procedure
NASA Astrophysics Data System (ADS)
Yamamoto, Naoko; Vreven, Thom; Robb, Michael A.; Frisch, Michael J.; Bernhard Schlegel, H.
1996-03-01
A direct method for the computation of energy second derivatives, and first derivatives which require the solution of the coupled perturbed MC-SCF equations, is presented. The two-electron derivative integral transformation is formulated in terms of 3/4 transformed integrals. The optimum strategy for the solution of the CP-MCSCF linear equations involves the solution in a Krylov space that involves all the right-hand sides. The feasibility of the method is demonstrated in a computation on the excited states of indene, styrene and octatetraene.
Synthesis of new polysialic acid derivatives.
Su, Yi; Kasper, Cornelia; Kirschning, Andreas; Dräger, Gerald; Berski, Silke
2010-09-01
In this paper we report the first synthesis of novel polysialic acid derivatives which is initiated by treatment of polysialic acid with EDC-HCl to yield the inter-residual delta-lactone. Subsequent reaction with amines or hydrazine gives the corresponding polysialic acid amides and hydrazide. Alkylation of the tetrabutylammonium salt of polysialic acid yields polysialic acid esters. In contrast a variety of N-derivatives of polysialic acid can be prepared starting from deacetylated polysialic acid. The N-derivatives prepared in this communication can be used for the Cu-catalyzed as well as Cu-free "click" chemistry. PMID:20602419
Synthesis of Hemigossypol and its Derivatives
Wei, Jun; Vander Jagt, David L.; Royer, Robert E.; Deck, Lorraine M.
2012-01-01
Hemigossypol (3), a sesquiterpene natural product, was previously isolated from Gossypium barbadense and was shown to display improved anti-fungal activity compared to gossypol (1), the disesquiterpene dimer of hemigossypol (3). Gossypol exhibits multiple biological activities. In order to study whether hemigossypol and it derivatives retain the various bioactivities of gossypol, we developed a short and convenient synthetic scheme to synthesize hemigossypol. This is the first de novo synthesis of this natural product. In addition derivatives of hemigossypol with various 2,5-alkyl substituents were synthesized. Modification of the synthetic scheme also afforded the natural product hemigossylic lactone (4) and its 2,5-substituted derivatives. PMID:22837586
Meson spectroscopy with derivative quark sources
Christof Gattringer; Leonid Ya. Glozman; C. B. Lang; Daniel Mohler; Sasa Prelovsek
2007-09-27
We present results for masses of light mesons obtained with the variational method using an enhanced basis of interpolating field operators with different quark smearings. The interpolators are constructed from Jacobi-smeared quarks of a Gaussian type as well as from derivative quark sources obtained by a covariant derivative acting on the Gaussian sources. For our analysis we use quenched gauge configurations with Chirally Improved quarks and the Luescher-Weisz gauge action on a 16^3 x 32 lattice with a = 0.148 fm. We discuss the influence of derivative sources on the overlap with excited states.
Carlos Díaz; María Luisa Valenzuela; Luis Zúñiga; Colm O’Dwyer
2009-01-01
The cyclic phosphazene trimers [N3P3(OC6H5)5OC5H4N·Ti(Cp)2Cl][PF6] (3), [N3P3(OC6H4CH2CN·Ti(Cp)2Cl)6][PF6]6 (4), [N3P3(OC6H4-But)5(OC6H4CH2CN·Ti(Cp)2Cl)][PF6] (5), [N3P3(OC6H5)5C6H4CH2CN·Ru(Cp)(PPh3)2][PF6] (6), [N3P3(OC6H5)5C6H4CH2CN·Fe(Cp)(dppe)][PF6] (7) and N3P3(OC6H5)5OC5H4N·W(CO)5 (8) were prepared and characterized. As a model, the simple compounds [HOC5H5N·Ti(Cp)2Cl]PF6 (1) and [HOC6H4CH2CN·Ti(Cp)2Cl]PF6 (2) were also prepared and characterized. Pyrolysis of the organometallic cyclic trimers in air yields metallic nanostructured\\u000a materials, which according to transmission and scanning electron microscopy (TEM\\/SEM), energy-dispersive X-ray
Casimir Energy Associated With Fractional Derivative Field
Lim, S. C. [Faculty of Engineering, Multimedia University, Cyberjaya 63100, Selangor (Malaysia)
2007-04-28
Casimir energy associated with fractional derivative scalar massless field at zero and positive temperature can be obtained using the regularization based on generalized Riemann zeta function of Epstein-Hurwitz type.
Cellulose Derivatives for Water Repellent Properties
Technology Transfer Automated Retrieval System (TEKTRAN)
Synthesis and structural characterizations of nitro-benzyl cellulose, amino-benzyl cellulose and pentafluoro –benzyl cellulose were carried out. Cellulose derivatives were synthesized by etherification process in lithium chloride/N,N-dimethylacetamide homogeneous solution. Nitrobenzylation was effec...
Direct synthesis of pyridine and pyrimidine derivatives
Hill, Matthew D. (Matthew Dennis)
2008-01-01
I. Synthesis of Substituted Pyridine Derivatives via the Ruthenium-Catalyzed Cycloisomerization of 3-Azadienynes. The two-step conversion of various N-vinyl and N-aryl amides to the corresponding substituted pyridines and ...
Phytol-Derived Novel Isoprenoid Immunostimulants
Chowdhury, Roshni Roy; Ghosh, Swapan K.
2012-01-01
This review describes the adjuvanticity of novel diterpenoids (synthetic phytol derivatives) compared to some commercially available adjuvants. The efficacy of the phytol-derived immunostimulants was evaluated in terms of their ability to activate innate immunity, amplify various antigen-specific immune responses, and engender immunological memory with no discernible adverse effects in both competent and immune-deficient mice. The profile that emerges out of these studies reveals that the phytol derivatives are excellent immunostimulants, superior to a number of commercial adjuvants in terms of long-term memory induction and activation of both innate and acquired immunity. Additionally, the phytol-derived compounds have no cumulative inflammatory or toxic effects even in immuno-compromised mice. PMID:22566931
Polyimides Derived from Novel Asymmetric Benzophenone Dianhydrides
NASA Technical Reports Server (NTRS)
Chuang, Chun-Hua (Inventor)
2015-01-01
This invention relates to the composition and processes for preparing thermoset polyimides derived from an asymmetric dianhydride, namely 2,3,3',4'-benzophenone dianhydride (a-BTDA) with at least one diamine, and a monofunctional terminal endcaps. The monofunctional terminating groups include 4-phenylethynylphthalic anhydride ester-acid derivatives, phenylethyl trimellitic anhydride (PETA) and its ester derivatives as well as 3-phenylethynylaniline. The process of polyimide composite comprises impregnating monomer reactants of dianhydride or its ester-acid derivatives, diamine and with monofunctional reactive endcaps into glass, carbon, quartz or synthetic fibers and fabrics, and then stack up into laminates and subsequently heated to between 150-375.degree. C. either at atmosphere or under pressure to promote the curing and crosslinking of the reactive endcaps to form a network of thermoset polyimides.
MANGROVE-DERIVED NUTRIENTS AND CORAL REEFS
Understanding the consequences of the declining global cover of mangroves due to anthropogenic disturbance necessitates consideration of how mangrove-derived nutrients contribute to threatened coral reef systems. We sampled potential sources of organic matter and a suite of sessi...
DERIVED CATEGORIES OF CUBIC FOURFOLDS ALEXANDER KUZNETSOV
Tschinkel, Yuri
DERIVED CATEGORIES OF CUBIC FOURFOLDS ALEXANDER KUZNETSOV Abstract. We discuss the structure in mathematics. 1 #12;2 ALEXANDER KUZNETSOV The "only if" part of the above is a special case of a more general
Synthesis of 5-substituted uracil derivatives.
Ressner, E C; Fraher, P; Edelman, M S; Mertes, M P
1976-01-01
The synthesis of a series of 5-substituted uracil derivatives is described. 5-Bromoacetyluracil (2a) was converted to the glycolyl (2b), glycyl (2c), N,N-dimethylglycyl (2d), 4-imidazolyl (3), and 2-amino-4-thiazolyl (4) derivatives. 5-Formyluracil (5) was used in the preparation of the 2-imidazolyl (6), the 3-acrylic acid (7b), the ester (7a), and the 3-N,N-dimethylacrylamide (8) derivatives. A Mannich reaction converted 5-acetyluracil to the amino ketone 9 which was reduced to give the 3-dimethylamino-1-propanol derivative 10. Compounds 2b,d,3,4,6, and 7b failed to inhibit the growth of Escherichia coli B and Staphylococcus aureus. PMID:1107549
On Positive Functions with Positive Derivatives
ERIC Educational Resources Information Center
Dobbs, David E.
2002-01-01
Three proofs are given for the fact that the derivative of an everywhere-positive non-constant real polynomial function must change sign. This self-contained note could find classroom use in courses on calculus or abstract algebra.
Real estate derivatives : products and prospects
Eisenberg, Oriel
2013-01-01
The paper reviews the development, structure and trade of past real estate equity hedging instruments. The reviewed products represent a wide array of real estate derivatives, covering multiple property types, index ...
Derivatives of the Stochastic Growth Rate
Steinsaltz, David; Tuljapurkar, Shripad; Horvitz, Carol
2011-01-01
We consider stochastic matrix models for population driven by random environments which form a Markov chain. The top Lyapunov exponent a, which describes the long-term growth rate, depends smoothly on the demographic parameters (represented as matrix entries) and on the parameters that define the stochastic matrix of the driving Markov chain. The derivatives of a — the “stochastic elasticities” — with respect to changes in the demographic parameters were derived by Tuljapurkar (1990). These results are here extended to a formula for the derivatives with respect to changes in the Markov chain driving the environments. We supplement these formulas with rigorous bounds on computational estimation errors, and with rigorous derivations of both the new and the old formulas. PMID:21463645
Catalytic combustion of coal-derived liquids
NASA Technical Reports Server (NTRS)
Bulzan, D. L.; Tacina, R. R.
1981-01-01
A noble metal catalytic reactor was tested with three grades of SRC 2 coal derived liquids, naphtha, middle distillate, and a blend of three parts middle distillate to one part heavy distillate. A petroleum derived number 2 diesel fuel was also tested to provide a direct comparison. The catalytic reactor was tested at inlet temperatures from 600 to 800 K, reference velocities from 10 to 20 m/s, lean fuel air ratios, and a pressure of 3 x 10 to the 5th power Pa. Compared to the diesel, the naphtha gave slightly better combustion efficiency, the middle distillate was almost identical, and the middle heavy blend was slightly poorer. The coal derived liquid fuels contained from 0.58 to 0.95 percent nitrogen by weight. Conversion of fuel nitrogen to NOx was approximately 75 percent for all three grades of the coal derived liquids.
SCM Forcing Data Derived from NWP Analyses
Jakob, Christian
Forcing data, suitable for use with single column models (SCMs) and cloud resolving models (CRMs), have been derived from NWP analyses for the ARM (Atmospheric Radiation Measurement) Tropical Western Pacific (TWP) sites of Manus Island and Nauru.
Deriving Mathisson - Papapetrou equations from relativistic pseudomechanics
R. R. Lompay
2005-03-12
It is shown that the equations of motion of a test point particle with spin in a given gravitational field, so called Mathisson - Papapetrou equations, can be derived from Euler - Lagrange equations of the relativistic pseudomechanics -- relativistic mechanics, which side by side uses the conventional (commuting) and Grassmannian (anticommuting) variables. In this approach the known difficulties of the Mathisson - Papapetrou equations, namely, the problem of the choice of supplementary conditions and the problem of higher derivatives are not appear.
On computing Laplace's coefficients and their derivatives.
NASA Astrophysics Data System (ADS)
Gerasimov, I. A.; Vinnikov, E. L.
The algorithm of computing Laplace's coefficients and their derivatives is proposed with application of recurrent relations. The A.G.M.-method is used for the calculation of values L0(0), L0(1). The FORTRAN-program corresponding to the algorithm is given. The precision control was provided with numerical integrating by Simpsons method. The behavior of Laplace's coefficients and their third derivatives whith varying indices K, n for fixed values of the ?-parameter is presented graphically.
Duality completion of higher derivative corrections
Hadi Godazgar; Mahdi Godazgar
2013-07-22
We present a new method for completing higher derivative corrections for theories that exhibit duality symmetries under reduction. This proposal is based on the observation that duality symmetry in the reduced theory highly constrains the form of the unreduced theory. We apply this idea to closed bosonic string theory and complete the Riemann squared term to simply derive the known full tree-level effective action to order alpha'.
Cobalt-substituted derivatives of Carcinus hemocyanin
Luigi Bubacco; Mariano Beltramini; Benedetto Salvato; Richard S. Magliozzo
1990-01-01
Summary Four derivatives ofCarcinus maenas hemocyanin containing Co(II) in the active site have been prepared under different experimental conditions. Two of them contain one Co(II) ion\\/active site and most probably represent isomeric forms containing Co(II) either in the ‘fast-reacting’ or in the ‘slow-reacting’ position within the active site. A third derivative contains two Co(II) ions active site, which reproduces the
Dependency Structures Derived from Minimalist Grammars
NASA Astrophysics Data System (ADS)
Boston, Marisa Ferrara; Hale, John T.; Kuhlmann, Marco
This paper provides an interpretation of Minimalist Grammars [16],[17] in terms of dependency structures. Under this interpretation, merge operations derive projective dependency structures, and movement operations introduce both non-projectivity and illnestedness. This new characterization of the generative capacity of Minimalist Grammar makes it possible to discuss the linguistic relevance of non-projectivity and illnestedness. This in turn provides insight into grammars that derive structures with these properties.
Financial derivatives in power marketing: The basics
Ramesh, V.C.; Ghosh, K. [Illinois Inst. of Tech., Chicago, IL (United States). Dept. of Electrical and Computer Engineering
1996-11-01
With the ongoing changes in the power industry worldwide, electricity is beginning to be traded like other commodities. The use of financial derivative instruments in power markets is on the rise. The purpose of this paper is to explain the role of these derivatives in risk management which is vital for survival in the increasingly competitive industry. Starting with the familiar cash markets, the paper discusses the basics of futures, options, and swap markets as applied to electric energy trading.
Resolution enhancement in second-derivative spectra.
Czarnecki, Miros?aw A
2015-01-01
Derivative spectroscopy is a powerful tool for the resolution enhancement in infrared, near-infrared, Raman, ultraviolet-visible, nuclear magnetic resonance, electron paramagnetic resonance, and fluorescence spectroscopy. Despite its great significance in analytical chemistry, not all aspects of the applications of this method have been explored as yet. This is the first systematic study of the parameters that influence the resolution enhancement in the second derivative spectra. The derivative spectra were calculated with the Savitzky-Golay method with different window size (5, 15, 25) and polynomial order (2, 4). The results obtained in this work show that the resolution enhancement in the second derivative spectra strongly depends on the data spacing in the original spectra, window size, polynomial order, and peak profile. As shown, the resolution enhancement is related to variations in the width of the peaks upon the differentiation. The present study reveals that in order to maximize the separation of the peaks in the second derivative spectra, the original spectra should be recorded at high resolution and differentiated using a small window size and high polynomial order. However, working with the real spectra one has to compromise between the noise reduction and optimization of the resolution enhancement in the second derivative spectra. PMID:25499557
Toward an iron(II) spin-crossover grafted phosphazene polymer.
Davidson, Ross J; Ainscough, Eric W; Brodie, Andrew M; Jameson, Geoffrey B; Waterland, Mark R; Allcock, Harry R; Hindenlang, Mark D; Moubaraki, Boujemaa; Murray, Keith S; Gordon, Keith C; Horvath, Raphael; Jameson, Guy N L
2012-08-01
Two new cyclotriphosphazene ligands with pendant 2,2':6',2?-terpyridine (Terpy) moieties, namely, (pentaphenoxy){4-[2,6-bis(2-pyridyl)]pyridoxy}cyclotriphosphazene (L(1)), (pentaphenoxy){4-[2,6-terpyridin-4-yl]phenoxy}cyclotriphosphazene (L(2)), and their respective polymeric analogues, L(1P) and L(2P), were synthesized. These ligands were used to form iron(II) complexes with an Fe(II)Terpy(2) core. Variable-temperature resonance Raman, UV-visible, and Mössbauer spectroscopies with magnetic measurements aided by density functional theory calculations were used to understand the physical characteristics of the complexes. By a comparison of measurements, the polymers were shown to behave in the same way as the cyclotriphosphazene analogues. The results showed that spin crossover (SCO) can be induced to start at high temperatures by extending the spacer length of the ligand to that in L(2) and L(2P); this combination provides a route to forming a malleable SCO material. PMID:22780572
Second virial coefficient of poly[(2,4-dichlorophenoxy)(phenoxy)phosphazene
NASA Astrophysics Data System (ADS)
Wohlfarth, Ch.
This document is part of Subvolume D2 'Polymer Solutions - Physical Properties and their Relations I (Thermodynamic Properties: PVT -Data and miscellaneous Properties of polymer Solutions) of Volume 6 `Polymers' of Landolt-Börnstein - Group VIII `Advanced Materials and Technologies'.
Wang, Shu-Gen; Jiang, Xin; Chen, Peng-Cheng; Yu, An-Guo; Huang, Xiao-Jun
2012-01-01
A core/sheath nanofiber membrane with poly[bis(p-methylphenoxy)]phospha-zene (PMPPh) as the sheath and easily spinnable polyacrylonitrile (PAN) as the core was prepared via a coaxial electrospinning process. Field-emission scanning electron microscopy and transmission electron microscopy were used to characterize the morphology of the nanofiber membrane. It was found that the concentration of the PAN spinning solution and the ratio of the core/sheath solution flow rates played a decisive role in the coaxial electrospinning process. In addition, the stabilized core/sheath PMPPh nanofiber membrane was investigated as a support for enzyme immobilization because of its excellent biocompatibility, high surface/volume ratio, and large porosity. Lipase from Candida rugosa was immobilized on the nanofiber membrane by adsorption. The properties of the immobilized lipase on the polyphosphazene nanofiber membrane were studied and compared with those of a PAN nanofiber membrane. The results showed that the adsorption capacity (20.4 ± 2.7 mg/g) and activity retention (63.7%) of the immobilized lipase on the polyphosphazene nanofiber membrane were higher than those on the PAN membrane. PMID:23203055
Phosphazene based multicentered naked-eye fluorescent sensor with high selectivity for Fe3+ ions.
Kagit, Reyhan; Yildirim, Mehmet; Ozay, Ozgur; Yesilot, Serkan; Ozay, Hava
2014-02-17
A novel on/off fluorescent rhodamine-based hexapodal Fe(3+) probe (L) containing a cyclotriphosphazene core was synthesized by an azide-alkyne "click-reaction". The synthesized compounds (1-5 and L) were characterized by FT-IR; (1)H, (13)C, and (31)P NMR; and MALDI MS spectrometry. The optical sensor features for the Fe(3+) complex of L were investigated by UV-vis and fluorescence spectroscopy. The stoichiometry of L-Fe(3+) complex was found to be 1:3 (ligand/metal ion), and the detection limit of L was determined as 4.8 ?M (0.27 mg L(-1)) for Fe(3+) ions. The reusability of the sensor was tested by the addition of ethylenediamine to L-Fe(3+) complex solutions followed by the addition of Fe(3+) solution. PMID:24498930
Second virial coefficient of poly[bis(3-chlorophenoxy)phosphazene
NASA Astrophysics Data System (ADS)
Wohlfarth, Ch.
This document is part of Subvolume D2 'Polymer Solutions - Physical Properties and their Relations I (Thermodynamic Properties: PVT -Data and miscellaneous Properties of polymer Solutions) of Volume 6 `Polymers' of Landolt-Börnstein - Group VIII `Advanced Materials and Technologies'.
Tetrahydropentalenyl-phosphazene constrained geometry complexes of rare-earth metal alkyls.
Hangaly, Noa K; Petrov, Alexander R; Elfferding, Michael; Harms, Klaus; Sundermeyer, Jörg
2014-05-21
Reactions of Cp™HPPh2 (1, diphenyl(4,4,6,6-tetramethyl-1,4,5,6-tetrahydropentalen-2-yl)phosphane) with the organic azides AdN3 and DipN3 (Ad = 1-adamantyl; Dip = 2,6-di-iso-propylphenyl) led to the formation of two novel CpPN ligands: P-amino-cyclopentadienylidene-phosphorane (Cp™PPh2NHAd; L(Ad)H) and P-cyclopentadienyl-iminophosphorane (Cp™HPPh2NDip; L(Dip)H). Both were characterized by NMR spectroscopy and X-ray structure analysis. For both compounds only one isomer was observed. Neither possesses any detectable prototropic or elementotropic isomers. Reactions of these ligands with [Lu(CH2SiMe3)3(thf)2] or with rare-earth metal halides and three equivalents of LiCH2SiMe3 produced the desired bis(alkyl) Cp™PN complexes: [{Cp™PN}M(CH2SiMe3)2] (M = Sc (1(Ad), 1(Dip)), Lu (2(Ad), 2(Dip)), Y (3(Ad), 3(Dip)), Sm (4(Ad)), Nd (5(Ad)), Pr (6(Ad)), Yb (7(Ad))). These complexes were characterized by extensive NMR studies for the diamagnetic and the paramagnetic complexes with full signal assignment. An almost mirror inverted order of the paramagnetic shifts has been observed for ytterbium complex 7(Ad) compared to 4(Ad), 5(Ad) and 6(Ad). For the assignment of the NMR signals [{?(1)?:??(5)-C5Me4PMe2NAd}Yb(CH2SiMe3)2] 7 was synthesized, characterized and the (1)H NMR signals were compared to 7(Ad) and to other paramagnetic lanthanide complexes with the same ligand. 1(Ad), 2(Ad), 2(Dip), 3(Ad) and 3(Dip) were characterized by X-ray structure analysis revealing a sterically congested constrained geometry structure. PMID:24671310
Phosphazene Based Additives for Improvement of Safety and Battery Lifetimes in Lithium-Ion Batteries
Mason K Harrup; Kevin L Gering; Harry W Rollins; Sergiy V Sazhin; Michael T Benson; David K Jamison; Christopher J Michelbacher
2011-01-01
There need to be significant improvements made in lithium-ion battery technology, principally in the areas of safety and useful lifetimes to truly enable widespread adoption of large format batteries for the electrification of the light transportation fleet. In order to effect the transition to lithium ion technology in a timely fashion, one promising next step is through improvements to the
Crystallisation and crystal forms of carbohydrate derivatives
NASA Astrophysics Data System (ADS)
Lennon, Lorna
This thesis is focused on the synthesis and solid state analysis of carbohydrate derivatives, including many novel compounds. Although the synthetic chemistry surrounding carbohydrates is well established in the literature, the crystal chemistry of carbohydrates is less well studied. Therefore this research aims to improve understanding of the solid state properties of carbohydrate derivatives through gaining more information on their supramolecular bonding. Chapter One focuses on an introduction to the solid state of organic compounds, with a background to crystallisation, including issues that can arise during crystal growth. Chapter Two is based on glucopyranuronate derivatives which are understudied in terms of their solid state forms. This chapter reports on the formation of novel glucuronamides and utilising the functionality of the amide bond for crystallisation. TEMPO oxidation was completed to form glucopyranuronates by oxidation of the primary alcohol groups of glucosides to the carboxylic acid derivatives, to increase functionality for enhanced crystal growth. Chapter Three reports on the synthesis of glucopyranoside derivatives by O-glycosylation reactions and displays crystal structures, including a number of previously unsolved acetate protected and deprotected crystal structures. More complex glycoside derivatives were also researched in an aim to study the resultant supramolecular motifs. Chapter Four contains the synthesis of aryl cellobioside derivatives including the novel crystal structures that were solved for the acetate protected and deprotected compounds. Research was carried out to determine if 1-deoxycellodextrins could act as putative isostructures for cellulose. Our research displays the presence of isostructural references with 1-deoxycellotriose shown to be similar to cellulose III11, 1-deoxycellotetraose correlates with cellulose IV11 and 1-deoxycellopentose shows isostructurality similar to that of cellulose II. Chapter Five contains the full experimental details and spectral characterisation of all novel compounds synthesised in this project and relevant crystallographic information.
New steroid derivative with hypoglycemic activity
Lauro, Figueroa-Valverde; Francisco, Díaz-Cedillo; Lenin, Hau-Heredia; Elodia, García-Cervera; Eduardo, Pool-Gómez; Marcela, Rosas-Nexticapa; Bety, Sarabia-Alcocer
2014-01-01
Data indicates that some steroid derivatives may induce changes on glucose levels; nevertheless, data are very confusing. Therefore, more pharmacological data are needed to characterize the activity induced by the steroid derivatives on glucose levels. The aim of this study was to synthesize a new steroid derivative for evaluate its hypoglycemic activity. The effects of steroid derivative on glucose concentration were evaluated in a diabetic animal model using glibenclamide and metformin as controls. In addition, the pregnenolone-dihydrotestosterone conjugate was bound to Tc-99m using radioimmunoassay methods, to evaluate the pharmacokinetics of the steroid derivative over time. The results showed that the pregnenolone-dihydrotestosterone conjugate induces changes on the glucose levels in similar form than glibenclamide. Other data showed that the biodistribution of Tc-99m-steroid derivativein brain was higher in comparison with spleen, stomach, intestine liver and kidney. In conclusion, the pregnenolone-dihydrotestosterone conjugate exerts hypoglycemic activity and this phenomenon could depend of its physicochemical properties which could be related to the degree of lipophilicity of the steroidderivative. PMID:25550906
Structure Activity Relationship of Brevenal Hydrazide Derivatives
Goodman, Allan; McCall, Jennifer R.; Jacocks, Henry M.; Thompson, Alysha; Baden, Daniel; Abraham, William M.; Bourdelais, Andrea
2014-01-01
Brevenal is a ladder frame polyether produced by the dinoflagellate Karenia brevis. This organism is also responsible for the production of the neurotoxic compounds known as brevetoxins. Ingestion or inhalation of the brevetoxins leads to adverse effects such as gastrointestinal maladies and bronchoconstriction. Brevenal shows antagonistic behavior to the brevetoxins and shows beneficial attributes when administered alone. For example, in an asthmatic sheep model, brevenal has been shown to increase tracheal mucosal velocity, an attribute which has led to its development as a potential treatment for Cystic Fibrosis. The mechanism of action of brevenal is poorly understood and the exact binding site has not been elucidated. In an attempt to further understand the mechanism of action of brevenal and potentially develop a second generation drug candidate, a series of brevenal derivatives were prepared through modification of the aldehyde moiety. These derivatives include aliphatic, aromatic and heteroaromatic hydrazide derivatives. The brevenal derivatives were tested using in vitro synaptosome binding assays to determine the ability of the compounds to displace brevetoxin and brevenal from their native receptors. A sheep inhalation model was used to determine if instillation of the brevenal derivatives resulted in bronchoconstriction. Only small modifications were tolerated, with larger moieties leading to loss of affinity for the brevenal receptor and bronchoconstriction in the sheep model. PMID:24686558
Derivation of Completely Cell Culture-Derived Mice from Early-Passage Embryonic Stem Cells
Andras Nagy; Janet Rossant; Reka Nagy; Wanda Abramow-Newerly; John C. Roder
1993-01-01
Several newly generated mouse embryonic stem (ES) cell lines were tested for their ability to produce completely ES cell-derived mice at early passage numbers by ES cell leftrightarrow tetraploid embryo aggregation. One line, designated R1, produced live offspring which were completely ES cell-derived as judged by isoenzyme analysis and coat color. These cell culture-derived animals were normal, viable, and fertile.
Chromone Derivatives from a Sponge-Derived Strain of the Fungus Corynespora cassiicola.
Zhao, Dong-Lin; Shao, Chang-Lun; Gan, Li-She; Wang, Mei; Wang, Chang-Yun
2015-02-27
Twelve new chromone derivatives, corynechromones A-L (1-12), were isolated from the sponge-derived fungus Corynespora cassiicola XS-200900I7. Among them, 1/2, 3/4, 5/6, and 7/8 were pairs of epimers. The planar structures were determined by extensive NMR spectroscopic data. The absolute configurations of 1-10 were assigned by the modified Mosher's method and TDDFT ECD calculations together with comparison of their CD spectra. These are the first chromone derivatives reported from the genus Corynespora. A possible rule to determine the absolute configurations at C-2 in chromone derivatives by CD was proposed. PMID:25594263
Second derivatives for approximate spin projection methods
NASA Astrophysics Data System (ADS)
Thompson, Lee M.; Hratchian, Hrant P.
2015-02-01
The use of broken-symmetry electronic structure methods is required in order to obtain correct behavior of electronically strained open-shell systems, such as transition states, biradicals, and transition metals. This approach often has issues with spin contamination, which can lead to significant errors in predicted energies, geometries, and properties. Approximate projection schemes are able to correct for spin contamination and can often yield improved results. To fully make use of these methods and to carry out exploration of the potential energy surface, it is desirable to develop an efficient second energy derivative theory. In this paper, we formulate the analytical second derivatives for the Yamaguchi approximate projection scheme, building on recent work that has yielded an efficient implementation of the analytical first derivatives.
Horava gravity with mixed derivative terms
Mattia Colombo; A. Emir Gumrukcuoglu; Thomas P. Sotiriou
2014-10-23
Horava gravity has been constructed so as to exhibit anisotropic scaling in the ultraviolet, as this renders the theory power-counting renormalizable. However, when coupled to matter, the theory has been shown to suffer from quadratic divergences. A way to cure these divergences is to add terms with both time and space derivatives. We consider this extended version of the theory in detail. We perform a perturbative analysis that includes all modes, determine the propagators and discuss how including mixed-derivative terms affects them. We also consider the Lifshitz scalar with mixed-derivative terms as a toy model for power counting arguments and discuss the influence of such terms on renormalizability.
Stratospheric Methane Derived from Aura MLS Measurements
NASA Astrophysics Data System (ADS)
Minschwaner, K. R.; Manney, G. L.; Lambert, A.; Pumphrey, H. C.; Walker, K. A.
2011-12-01
The stratospheric distribution of methane has been derived using measurements of water vapor, carbon monoxide, and nitrous oxide from the Microwave Limb Sounder (MLS) instrument on the Aura satellite. The method utilizes trace gas correlations and separation of air mass regimes based on measurements from the Atmospheric Chemistry Experiment - Fourier Transform Spectrometer (ACE-FTS) on the SCISAT I satellite. The reliable vertical extent of derived methane from MLS ranges from near the tropopause through the upper stratosphere, and covers all seasons and latitudes observed by MLS over the course of the Aura mission from 2004 to 2011. Methane distributions and their time evolution are compared to simulations from the SLIMCAT chemical transport model. Applications of the derived CH4 product include assessment of the CO photochemical budget, interpretation of the upper stratospheric ClO time series from MLS and the chlorine budget, and diagnosis of trace gas transport during polar vortex mixing events and stratospheric sudden warmings.
Antimicrobial evaluation of some arylsulfanylpyrazinecarboxylic acid derivatives.
Jampilek, Josef; Dolezal, Martin; Buchta, Vladimir
2007-05-01
The radical-ionic coupling of chloropyrazine-2-carboxylic acid derivatives with methoxybenzenethiols, carried out in the presence of a heterogeneous copper catalyst, provided the series of 6- or 5- or 3-(4-methoxyphenyl)sulfanyl-pyrazine-2-carboxylic acid derivatives as well as 6- or 5- or 3-(3-methoxyphenyl)sulfanylpyrazine-2-carboxylic acid derivatives. The prepared compounds were evaluated as potential antifungal agents and new antituberculotics. Their preliminary in vitro evaluation of antimycobacterial activity according to the international program with the Tuberculosis Antimicrobial Acquisition and Coordinating Facility (TAACF) is presented. Several compounds showed an interesting activity in the preliminary screening with a percentage growth inhibition of the virulent Mycobacterium tuberculosis H(37)Rv between 50 to 100% at the concentration 6.25 microg/mL. Structure-activity relationships among the chemical structure, the physical properties and the biological activities of the evaluated compounds are discussed in the article. PMID:17504199
Increment of antimycobaterial activity on lichexanthone derivatives.
Micheletti, Ana Camila; Honda, Neli Kika; Pavan, Fernando R; Leite, Clarice Q F; Matos, Maria de Fatima Cepa; Perdomo, Renata Trentin; Bogo, Danielle; Alcantara, Glaucia Braz; Beatriz, Adilson
2013-11-01
A new dihydropyranexanthone derived from the natural xanthone lichexanthone (1) was synthesised and, together with other 18 derivatives including ?-bromo and ?-aminoalkoxylxanthones (containing methyl, ethyl, propyl, tertbutylamino and piperidinyl moieties), were tested against Mycobacterium tuberculosis. Nine ?-aminoalkoxylxanthones showed good antimycobacterial activity, and their in vitro cytotoxicity was determined using VERO cells in order to calculate the selectivity index (SI). One of these nitrogenated xanthone derivatives showed very promising results, with MIC of 2.6 ?M and SI of 48. This MIC is comparable to values found in "first and second line" drugs commonly used to treat TB. In order to understand better about this compound, it was evaluated together with two other ones that showed good SI, against resistant clinical strains of M. tuberculosis to verify the existence of cross-resistance. A chemometrical approach was useful to establish a pattern of antitubercular activity among the group of ?-aminoalkoxylxanthones, according to some structural and chemical features. PMID:23106287
Derived Product Imagery from GOES-8.
NASA Astrophysics Data System (ADS)
Hayden, Christopher M.; Wade, Gary S.; Schmit, Timothy J.
1996-02-01
Derived product imagery (DPI) is a method of presenting quantitative meteorological information, derived from satellite measurements, as a color-coded image at single-pixel resolution. Its intended use is as animated sequences to observe trends in the displayed quantities, which for the GOES-8 are total precipitable water, lifted index, and surface skin temperature. Those products are produced once per hour, over the continental United States and the Gulf of Mexico. This paper reviews the development of the DPI and details the algorithm used for GOES-8. The quality of the products is discussed, and an example is given. The greatest value of the DPI probably lies in comparing a sequence of the satellite product with a sequence derived from a numerical forecast. In this way, deviation of the forecast from reality is readily exposed.
Xanthocidin derivatives as topoisomerase II? enzymatic inhibitors.
Takeda, Shuso; Yaji, Kentaro; Matsumoto, Kenji; Amamoto, Toshiaki; Shindo, Mitsuru; Aramaki, Hironori
2014-01-01
Few studies have examined xanthocidin, a biotic isolated from Streptomyces xanthocidicus in 1966, because its supply is limited. Based on its chemical structure, xanthocidin has the potential to become a lead compound in the production of agrochemicals and anti-cancer drugs; however, it is unstable under both basic and acidic conditions. We recently established the total synthesis of xanthocidin using the FeCl3-mediated Nazarov reaction, and obtained two stable derivatives (#1 and #2). The results of the present study demonstrated that these derivatives exhibited the inhibitory activity of topoisomerase II?, known as a molecular target for cancer chemotherapy, and this was attributed to the respective exo-methylene ketone group without DNA intercalation. The results obtained also suggest that these derivatives may have value as lead compounds in the synthesis of topoisomerase II? inhibitors. PMID:24492731
Dielectric transition of polyacrylonitrile derived carbon nanofibers
NASA Astrophysics Data System (ADS)
Li, Jiangling; Su, Shi; Zhou, Lei; Abbot, Andrew M.; Ye, Haitao
2014-09-01
The dielectric behavior of polyacrylonitrile derived carbon nanofibers formed at different carbonization temperatures was investigated using impedance spectroscopy. The impedance data are presented in the form of Cole-Cole plots and four equivalent electrical circuits are derived. It is found that by increasing carbonization temperature from 500 to 800 °C, a strong capacitive element in the parallel equivalent circuit is transformed into an inductive element, while the contact resistance and parallel resistance are significantly decreased. Along with the morphological and chemical structural evolution, respectively witnessed by scanning electron microscopy and Raman spectroscopy, the dielectric transition deduced from the transformation of electrical circuits can be correlated to the proposed microstructural changes of polyacrylonitrile derived carbon nanofibers and the interaction/interference among them.
Gateaux and Frechet Derivative in Intuitionistic Fuzzy Normed Linear spaces
B. Dinda; T. K. Samanta; U. K. Bera
2010-09-11
Intuitionistic Fuzzy derivative, Intuitionistic Fuzzy Gateaux derivative, Intuitionistic Fuzzy Fr\\'{e}chet derivative are defined and a few of their properties are studied. The relation between Intuitionistic Fuzzy Gateaux derivative and Intuitionistic Fuzzy Fr\\'{e}chet derivative are emphasized.
Halogenated coumarin derivatives as novel seed protectants.
Brooker, N; Windorski, J; Bluml, E
2008-01-01
Development of new and improved antifungal compounds that are target-specific is backed by a strong Federal, public and commercial mandate. Many plant-derived chemicals have proven fungicidal properties, including the coumarins (1,2-Benzopyrone) found in a variety of plants such as clover, sweet woodruff and grasses. Preliminary research has shown the coumarins to be a highly active group of molecules with a wide range of antimicrobial activity against both fungi and bacteria. It is believed that these cyclic compounds behave as natural pesticidal defence molecules for plants and they represent a starting point for the exploration of new derivative compounds possessing a range of improved antifungal activity. Within this study, derivatives of coumarin that were modified with halogenated side groups were screened for their antifungal activity against a range of soil-borne plant pathogenic fungi. Fungi included in this in vitro screen included Macrophomina phaseolina (charcoal rot), Phytophthora spp. (damping off and seedling rot), Rhizoctonia spp. (damping off and root rot) and Pythium spp. (seedling blight), four phylogenetically diverse and economically important plant pathogens. Studies indicate that these halogenated coumarin derivatives work very effectively in vitro to inhibit fungal growth and some coumarin derivatives have higher antifungal activity and stability as compared to the original coumarin compound alone. The highly active coumarin derivatives are brominated, iodinated and chlorinated compounds and results suggest that besides being highly active, very small amounts can be used to achieve LD100 rates. In addition to the in vitro fungal inhibition assays, results of polymer seed coating compatibility and phytotoxicity testing using these compounds as seed treatments will also be reported. These results support additional research in this area of natural pesticide development. PMID:19226745
D -split sequences and derived equivalences
Wei Hu; Changchang Xi
2011-01-01
In this paper, we introduce the so-called D-split sequences and show that each D-split sequence gives rise to a derived equivalence via a tilting module. In particular, we obtain derived equivalences from Auslander–Reiten sequences via BB-tilting modules (or from n-almost split sequences via n-BB-tilting modules), and Auslander–Reiten triangles. Further, we recover n-almost split sequences from n-BB-tilting modules over n-Auslander algebras.
High ethanol producing derivatives of Thermoanaerobacter ethanolicus
Ljungdahl, Lars G. (Athens, GA); Carriera, Laura H. (Athens, GA)
1983-01-01
Derivatives of the newly discovered microorganism Thermoanaerobacter ethanolicus which under anaerobic and thermophilic conditions continuously ferment substrates such as starch, cellobiose, glucose, xylose and other sugars to produce recoverable amounts of ethanol solving the problem of fermentations yielding low concentrations of ethanol using the parent strain of the microorganism Thermoanaerobacter ethanolicus are disclosed. These new derivatives are ethanol tolerant up to 10% (v/v) ethanol during fermentation. The process includes the use of an aqueous fermentation medium, containing the substrate at a substrate concentration greater than 1% (w/v).
Synthesis and antiplasmodial activity of lycorine derivatives.
Cedrón, Juan C; Gutiérrez, David; Flores, Ninoska; Ravelo, Angel G; Estévez-Braun, Ana
2010-07-01
Twenty seven lycorine derivatives were prepared and evaluated for their in vitro antimalarial activity against chloroquine-sensitive strains of Plasmodium falciparum. The best antiplasmodial activities were achieved with lycorine derivatives that present free hydroxyl groups at C-1 and C-2 or esterified as acetates or isobutyrates. The double bond C-2-C-3 is also important for the activity. Concerning to the antiplasmodial activity of the secolycorines, the higher values were obtained with the replacement of the methylenedioxy moiety by hydroxyl or acetate groups and with methyl substituent attached to the nitrogen atom. PMID:20627737
Geometric derivation of the quantum speed limit
Jones, Philip J.; Kok, Pieter [Department of Physics and Astronomy, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom)
2010-08-15
The Mandelstam-Tamm and Margolus-Levitin inequalities play an important role in the study of quantum-mechanical processes in nature since they provide general limits on the speed of dynamical evolution. However, to date there has been only one derivation of the Margolus-Levitin inequality. In this paper, alternative geometric derivations for both inequalities are obtained from the statistical distance between quantum states. The inequalities are shown to hold for unitary evolution of pure and mixed states, and a counterexample to the inequalities is given for evolution described by completely positive trace-preserving maps. The counterexample shows that there is no quantum speed limit for nonunitary evolution.
Special Relativity Derived from Spacetime Magma
Greensite, Fred
2014-01-01
We present a derivation of relativistic spacetime largely untethered from specific physical considerations, in constrast to the many physically-based derivations that have appeared in the last few decades. The argument proceeds from the inherent magma (groupoid) existing on the union of spacetime frame components and Euclidean which is consistent with an “inversion symmetry” constraint from which the Minkowski norm results. In this context, the latter is also characterized as one member of a class of “inverse norms” which play major roles with respect to various unital -algebras more generally. PMID:24959889
Terpenes from Marine-Derived Fungi
Ebel, Rainer
2010-01-01
Terpenes from marine-derived fungi show a pronounced degree of structural diversity, and due to their interesting biological and pharmacological properties many of them have aroused interest from synthetic chemists and the pharmaceutical industry alike. The aim of this paper is to give an overview of the structural diversity of terpenes from marine-derived fungi, highlighting individual examples of chemical structures and placing them in a context of other terpenes of fungal origin. Wherever possible, information regarding the biological activity is presented. PMID:20948911
High ethanol producing derivatives of Thermoanaerobacter ethanolicus
Ljungdahl, L.G.; Carriera, L.H.
1983-05-24
Derivatives of the newly discovered microorganism Thermoanaerobacter ethanolicus which under anaerobic and thermophilic conditions continuously ferment substrates such as starch, cellobiose, glucose, xylose and other sugars to produce recoverable amounts of ethanol solving the problem of fermentations yielding low concentrations of ethanol using the parent strain of the microorganism Thermoanaerobacter ethanolicus are disclosed. These new derivatives are ethanol tolerant up to 10% (v/v) ethanol during fermentation. The process includes the use of an aqueous fermentation medium, containing the substrate at a substrate concentration greater than 1% (w/v).
Elevation Derivatives for Mojave Desert Tortoise Habitat
Wallace, Cynthia S.A.; Gass, Leila
2008-01-01
This report describes the methods used to derive various elevation-derivative grids that were inputted to the Mojave Desert Tortoise Habitat model (L. Gass and others, unpub. data). These grids, which capture information on surface roughness and topographic characteristics, are a subset of the environmental datasets evaluated for the tortoise habitat model. This habitat model is of major importance to the U.S. Fish and Wildlife Service, which is charged with management of this threatened population, including relocating displaced tortoises to areas identified as suitable habitat.
A rigorous derivation of multicomponent diffusion laws
Zaibao Yang; Wen-An Yong; Yi Zhu
2015-02-12
This article is concerned with the dynamics of a mixture of gases. Under the assumption that all the gases are isothermal and inviscid, we show that the governing equations have an elegant conservation-dissipation structure. With the help of this structure, a multicomponent diffusion law is derived mathematically rigorously. This clarifies a long-standing non-uniqueness issue in the field for the first time. The multicomponent diffusion law derived here takes the spatial gradient of an entropic variable as the thermodynamic forces and satisfies a nonlinear version of the Onsager reciprocal relations.
New coumarin derivatives as carbonic anhydrase inhibitors.
Karata?, Mert Olgun; Alici, Bülent; Cakir, Umit; Cetinkaya, Engin; Demir, Dudu; Ergün, Adem; Gençer, Nahit; Arslan, Oktay
2014-06-01
In the current study, a series of 4-chloromethyl-7-hydroxy-coumarin derivatives containing imidazolium, benzimidazolium, bisbenzimidazolium and quaternary ammonium salts were synthesized, characterized and the inhibition effects of the derivatives on human carbonic anhydrases (hCA I and hCA II) were investigated as in vitro. Structures of these coumarins were confirmed by FT-IR, (1)H NMR, (13)C NMR and LC-MS analyses. Structure activity relationship study showed that 3d (IC50: 79 ?M for hCA I and 88 ?M for hCA II) performed higher inhibitory activity than others. PMID:23656671
Technology Transfer Automated Retrieval System (TEKTRAN)
Vegetable oils, their derivatives, and glycerin represent renewable raw materials that are firmly established components in many industrial products. Their use continues to be of interest to many researchers and the development of approaches to functionalize these compounds to derive oleochemicals ...
Barriers to growth in the US real estate derivatives market
Venter, Jani
2007-01-01
Commercial real estate is an important asset class but it does not yet have a well-developed derivatives market in the United States. A derivative is a contract that derives its value from an underlying index or asset. ...
40 CFR 721.10317 - Alkyl phosphate derivative (generic).
Code of Federal Regulations, 2013 CFR
2013-07-01
...2013-07-01 2013-07-01 false Alkyl phosphate derivative (generic). 721.10317...Chemical Substances § 721.10317 Alkyl phosphate derivative (generic). (a) Chemical...substance identified generically as alkyl phosphate derivative (PMN P-02-1040)...
40 CFR 721.10317 - Alkyl phosphate derivative (generic).
Code of Federal Regulations, 2014 CFR
2014-07-01
...2014-07-01 2014-07-01 false Alkyl phosphate derivative (generic). 721.10317...Chemical Substances § 721.10317 Alkyl phosphate derivative (generic). (a) Chemical...substance identified generically as alkyl phosphate derivative (PMN P-02-1040)...
32 CFR 2400.14 - Use of derivative classification.
Code of Federal Regulations, 2013 CFR
2013-07-01
...2013-07-01 2013-07-01 false Use of derivative classification. 2400.14 Section...TECHNOLOGY POLICY INFORMATION SECURITY PROGRAM Derivative Classification § 2400.14 Use of derivative classification. (a)...
18 CFR 367.1750 - Account 175, Derivative instrument assets.
Code of Federal Regulations, 2014 CFR
2014-04-01
...2014-04-01 false Account 175, Derivative instrument assets. 367.1750...Assets § 367.1750 Account 175, Derivative instrument assets. This account must include the amounts paid for derivative instruments, and the change...
40 CFR 721.1760 - Substituted benzotriazole derivatives.
Code of Federal Regulations, 2012 CFR
2012-07-01
... false Substituted benzotriazole derivatives. 721.1760 Section 721.1760...721.1760 Substituted benzotriazole derivatives. (a) Chemical substances and significant...generically as substituted benzotriazole derivatives (PMNs P-93-374 and...
17 CFR 240.16a-4 - Derivative securities.
Code of Federal Regulations, 2014 CFR
2014-04-01
...2014-04-01 2014-04-01 false Derivative securities. 240.16a-4 ...Securities Dealers § 240.16a-4 Derivative securities. (a) For purposes of section 16 of the Act, both derivative securities and the...
40 CFR 721.10324 - Thionocarbamate derivative (generic).
Code of Federal Regulations, 2013 CFR
2013-07-01
...2013-07-01 false Thionocarbamate derivative (generic). 721.10324 Section...Substances § 721.10324 Thionocarbamate derivative (generic). (a) Chemical substance...identified generically as thionocarbamate derivative (PMN P-03-362) is subject...
40 CFR 721.5925 - Bis heterocyclic phenylene derivative (generic).
Code of Federal Regulations, 2013 CFR
2013-07-01
... false Bis heterocyclic phenylene derivative (generic). 721.5925 Section...5925 Bis heterocyclic phenylene derivative (generic). (a) Chemical substance...generically as bis heterocyclic phenylene derivative (PMN P-01-0432) is subject...
76 FR 43957 - Modifications of Certain Derivative Contracts
Federal Register 2010, 2011, 2012, 2013, 2014
2011-07-22
...1545-BK13 Modifications of Certain Derivative Contracts AGENCY: Internal Revenue...when there is an assignment of certain derivative contracts. The text of those regulations...that the transfer or assignment of a derivative contract in certain situations is...
40 CFR 721.9740 - Brominated triazine derivative.
Code of Federal Regulations, 2010 CFR
2010-07-01
...2010-07-01 false Brominated triazine derivative. 721.9740 Section 721.9740... § 721.9740 Brominated triazine derivative. (a) Chemical substance and significant...generically as a brominated triazine derivative (PMN P-91-403) is subject...
40 CFR 721.646 - Aminofluoran derivative (generic name).
Code of Federal Regulations, 2010 CFR
2010-07-01
...2010-07-01 false Aminofluoran derivative (generic name). 721.646 Section...Substances § 721.646 Aminofluoran derivative (generic name). (a) Chemical...identified generically as aminofluoran derivative (PMN P-95-512) is subject...
40 CFR 721.10172 - Alkylamide derivative (generic).
Code of Federal Regulations, 2011 CFR
2011-07-01
... 2011-07-01 false Alkylamide derivative (generic). 721.10172 Section...Substances § 721.10172 Alkylamide derivative (generic). (a) Chemical substance...identified generically as alkylamide derivative (PMN P-03-633) is subject...
40 CFR 721.10330 - Pyrazolone derivative (generic).
Code of Federal Regulations, 2013 CFR
2013-07-01
... 2013-07-01 false Pyrazolone derivative (generic). 721.10330 Section...Substances § 721.10330 Pyrazolone derivative (generic). (a) Chemical substance...identified generically as pyrazolone derivative (PMN P-03-722) is subject...
40 CFR 721.2025 - Substituted phenylimino carbamate derivative.
Code of Federal Regulations, 2012 CFR
2012-07-01
... Substituted phenylimino carbamate derivative. 721.2025 Section 721.2025... Substituted phenylimino carbamate derivative. (a) Chemical substance and significant...as a substituted phenylimino carbamate derivative (PMN P-91-487) is subject...
40 CFR 721.9079 - Dihydro quinacridone derivative (generic).
Code of Federal Regulations, 2012 CFR
2012-07-01
...2012-07-01 false Dihydro quinacridone derivative (generic). 721.9079 Section... § 721.9079 Dihydro quinacridone derivative (generic). (a) Chemical substance...identified generically as dihydro quinacridone derivative (PMN P-01-397) is subject...
40 CFR 721.10317 - Alkyl phosphate derivative (generic).
Code of Federal Regulations, 2012 CFR
2012-07-01
...2012-07-01 false Alkyl phosphate derivative (generic). 721.10317 Section...Substances § 721.10317 Alkyl phosphate derivative (generic). (a) Chemical substance...identified generically as alkyl phosphate derivative (PMN P-02-1040) is subject...
14 CFR 1203.500 - Use of derivative classification.
Code of Federal Regulations, 2011 CFR
2011-01-01
...2011-01-01 2010-01-01 true Use of derivative classification. 1203.500 Section...ADMINISTRATION INFORMATION SECURITY PROGRAM Derivative Classification § 1203.500 Use of derivative classification. The...
40 CFR 721.1760 - Substituted benzotriazole derivatives.
Code of Federal Regulations, 2013 CFR
2013-07-01
... false Substituted benzotriazole derivatives. 721.1760 Section 721.1760...721.1760 Substituted benzotriazole derivatives. (a) Chemical substances and significant...generically as substituted benzotriazole derivatives (PMNs P-93-374 and...
40 CFR 721.646 - Aminofluoran derivative (generic name).
Code of Federal Regulations, 2011 CFR
2011-07-01
...2011-07-01 false Aminofluoran derivative (generic name). 721.646 Section...Substances § 721.646 Aminofluoran derivative (generic name). (a) Chemical...identified generically as aminofluoran derivative (PMN P-95-512) is subject...
18 CFR 367.1750 - Account 175, Derivative instrument assets.
Code of Federal Regulations, 2011 CFR
2011-04-01
...2011-04-01 false Account 175, Derivative instrument assets. 367.1750...Assets § 367.1750 Account 175, Derivative instrument assets. This account must include the amounts paid for derivative instruments, and the change...
32 CFR 2400.14 - Use of derivative classification.
Code of Federal Regulations, 2011 CFR
2011-07-01
...2011-07-01 2011-07-01 false Use of derivative classification. 2400.14 Section...TECHNOLOGY POLICY INFORMATION SECURITY PROGRAM Derivative Classification § 2400.14 Use of derivative classification. (a)...
18 CFR 367.2440 - Account 244, Derivative instrument liabilities.
Code of Federal Regulations, 2013 CFR
2013-04-01
...2013-04-01 false Account 244, Derivative instrument liabilities. 367.2440...Liabilities § 367.2440 Account 244, Derivative instrument liabilities. This account...the change in the fair value of all derivative instrument liabilities not...
40 CFR 721.1760 - Substituted benzotriazole derivatives.
Code of Federal Regulations, 2010 CFR
2010-07-01
... false Substituted benzotriazole derivatives. 721.1760 Section 721.1760...721.1760 Substituted benzotriazole derivatives. (a) Chemical substances and significant...generically as substituted benzotriazole derivatives (PMNs P-93-374 and...
40 CFR 721.646 - Aminofluoran derivative (generic name).
Code of Federal Regulations, 2013 CFR
2013-07-01
...2013-07-01 false Aminofluoran derivative (generic name). 721.646 Section...Substances § 721.646 Aminofluoran derivative (generic name). (a) Chemical...identified generically as aminofluoran derivative (PMN P-95-512) is subject...
40 CFR 721.10368 - Triphenodioxazine derivatives (generic).
Code of Federal Regulations, 2014 CFR
2014-07-01
...2014-07-01 false Triphenodioxazine derivatives (generic). 721.10368 Section... § 721.10368 Triphenodioxazine derivatives (generic). (a) Chemical substance...identified generically as triphenodioxazine derivatives (PMN P-10-84) is subject...
40 CFR 721.5925 - Bis heterocyclic phenylene derivative (generic).
Code of Federal Regulations, 2011 CFR
2011-07-01
... false Bis heterocyclic phenylene derivative (generic). 721.5925 Section...5925 Bis heterocyclic phenylene derivative (generic). (a) Chemical substance...generically as bis heterocyclic phenylene derivative (PMN P-01-0432) is subject...
14 CFR 1203.501 - Applying derivative classification markings.
Code of Federal Regulations, 2011 CFR
2011-01-01
...2011-01-01 2010-01-01 true Applying derivative classification markings. 1203.501...ADMINISTRATION INFORMATION SECURITY PROGRAM Derivative Classification § 1203.501 Applying derivative classification markings. Persons...
12 CFR 3.34 - OTC derivative contracts.
Code of Federal Regulations, 2014 CFR
2014-01-01
...2014-01-01 2014-01-01 false OTC derivative contracts. 3.34 Section 3...General Credit Risk § 3.34 OTC derivative contracts. (a) Exposure amount —(1) Single OTC derivative contract. Except as modified...
18 CFR 367.2440 - Account 244, Derivative instrument liabilities.
Code of Federal Regulations, 2010 CFR
2010-04-01
...2010-04-01 false Account 244, Derivative instrument liabilities. 367.2440...Liabilities § 367.2440 Account 244, Derivative instrument liabilities. This account...the change in the fair value of all derivative instrument liabilities not...
40 CFR 721.9079 - Dihydro quinacridone derivative (generic).
Code of Federal Regulations, 2010 CFR
2010-07-01
...2010-07-01 false Dihydro quinacridone derivative (generic). 721.9079 Section... § 721.9079 Dihydro quinacridone derivative (generic). (a) Chemical substance...identified generically as dihydro quinacridone derivative (PMN P-01-397) is subject...
40 CFR 721.9079 - Dihydro quinacridone derivative (generic).
Code of Federal Regulations, 2011 CFR
2011-07-01
...2011-07-01 false Dihydro quinacridone derivative (generic). 721.9079 Section... § 721.9079 Dihydro quinacridone derivative (generic). (a) Chemical substance...identified generically as dihydro quinacridone derivative (PMN P-01-397) is subject...
32 CFR 2400.14 - Use of derivative classification.
Code of Federal Regulations, 2014 CFR
2014-07-01
...2014-07-01 2014-07-01 false Use of derivative classification. 2400.14 Section...TECHNOLOGY POLICY INFORMATION SECURITY PROGRAM Derivative Classification § 2400.14 Use of derivative classification. (a)...
78 FR 66639 - Modifications of Certain Derivative Contracts
Federal Register 2010, 2011, 2012, 2013, 2014
2013-11-06
...1545-BK13 Modifications of Certain Derivative Contracts AGENCY: Internal Revenue...the transfer or assignment of certain derivative contracts. The final regulations provide...to the nonassigning counterparty to a derivative contract and an assignee on...
14 CFR 1203.500 - Use of derivative classification.
Code of Federal Regulations, 2013 CFR
2013-01-01
...2013-01-01 2013-01-01 false Use of derivative classification. 1203.500 Section...ADMINISTRATION INFORMATION SECURITY PROGRAM Derivative Classification § 1203.500 Use of derivative classification. The...
40 CFR 721.2025 - Substituted phenylimino carbamate derivative.
Code of Federal Regulations, 2011 CFR
2011-07-01
... Substituted phenylimino carbamate derivative. 721.2025 Section 721.2025... Substituted phenylimino carbamate derivative. (a) Chemical substance and significant...as a substituted phenylimino carbamate derivative (PMN P-91-487) is subject...
18 CFR 367.2440 - Account 244, Derivative instrument liabilities.
Code of Federal Regulations, 2011 CFR
2011-04-01
...2011-04-01 false Account 244, Derivative instrument liabilities. 367.2440...Liabilities § 367.2440 Account 244, Derivative instrument liabilities. This account...the change in the fair value of all derivative instrument liabilities not...
40 CFR 721.2025 - Substituted phenylimino carbamate derivative.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Substituted phenylimino carbamate derivative. 721.2025 Section 721.2025... Substituted phenylimino carbamate derivative. (a) Chemical substance and significant...as a substituted phenylimino carbamate derivative (PMN P-91-487) is subject...
40 CFR 721.5925 - Bis heterocyclic phenylene derivative (generic).
Code of Federal Regulations, 2012 CFR
2012-07-01
... false Bis heterocyclic phenylene derivative (generic). 721.5925 Section...5925 Bis heterocyclic phenylene derivative (generic). (a) Chemical substance...generically as bis heterocyclic phenylene derivative (PMN P-01-0432) is subject...
18 CFR 367.1750 - Account 175, Derivative instrument assets.
Code of Federal Regulations, 2013 CFR
2013-04-01
...2013-04-01 false Account 175, Derivative instrument assets. 367.1750...Assets § 367.1750 Account 175, Derivative instrument assets. This account must include the amounts paid for derivative instruments, and the change...
14 CFR 1203.500 - Use of derivative classification.
Code of Federal Regulations, 2010 CFR
2010-01-01
...2010-01-01 2010-01-01 false Use of derivative classification. 1203.500 Section...ADMINISTRATION INFORMATION SECURITY PROGRAM Derivative Classification § 1203.500 Use of derivative classification. The...
14 CFR 1203.500 - Use of derivative classification.
Code of Federal Regulations, 2012 CFR
2012-01-01
...2012-01-01 2012-01-01 false Use of derivative classification. 1203.500 Section...ADMINISTRATION INFORMATION SECURITY PROGRAM Derivative Classification § 1203.500 Use of derivative classification. The...
40 CFR 721.9079 - Dihydro quinacridone derivative (generic).
Code of Federal Regulations, 2014 CFR
2014-07-01
...2014-07-01 false Dihydro quinacridone derivative (generic). 721.9079 Section... § 721.9079 Dihydro quinacridone derivative (generic). (a) Chemical substance...identified generically as dihydro quinacridone derivative (PMN P-01-397) is subject...
40 CFR 721.10172 - Alkylamide derivative (generic).
Code of Federal Regulations, 2013 CFR
2013-07-01
... 2013-07-01 false Alkylamide derivative (generic). 721.10172 Section...Substances § 721.10172 Alkylamide derivative (generic). (a) Chemical substance...identified generically as alkylamide derivative (PMN P-03-633) is subject...
Nonlinear Frechet derivative and its De Wolf approximation
Wu, Ru-Shan
2012-01-01
We introduce and derive the nonlinear Frechet derivative for the acoustic wave equation. It turns out that the high order Frechet derivatives can be realized by consecutive applications of the scattering operator and a ...
40 CFR 721.10368 - Triphenodioxazine derivatives (generic).
Code of Federal Regulations, 2013 CFR
2013-07-01
...2013-07-01 false Triphenodioxazine derivatives (generic). 721.10368 Section... § 721.10368 Triphenodioxazine derivatives (generic). (a) Chemical substance...identified generically as triphenodioxazine derivatives (PMN P-10-84) is subject...
76 FR 51878 - Modifications of Certain Derivative Contracts; Correction
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-19
...1545-BK14 Modifications of Certain Derivative Contracts; Correction AGENCY: Internal...a transfer or assignment of certain derivative contracts does not result in an exchange...clearinghouse transfers or assigns a derivative contract to another dealer in...
40 CFR 721.5925 - Bis heterocyclic phenylene derivative (generic).
Code of Federal Regulations, 2010 CFR
2010-07-01
... false Bis heterocyclic phenylene derivative (generic). 721.5925 Section...5925 Bis heterocyclic phenylene derivative (generic). (a) Chemical substance...generically as bis heterocyclic phenylene derivative (PMN P-01-0432) is subject...
18 CFR 367.1750 - Account 175, Derivative instrument assets.
Code of Federal Regulations, 2012 CFR
2012-04-01
...2012-04-01 false Account 175, Derivative instrument assets. 367.1750...Assets § 367.1750 Account 175, Derivative instrument assets. This account must include the amounts paid for derivative instruments, and the change...
40 CFR 721.1760 - Substituted benzotriazole derivatives.
Code of Federal Regulations, 2011 CFR
2011-07-01
... false Substituted benzotriazole derivatives. 721.1760 Section 721.1760...721.1760 Substituted benzotriazole derivatives. (a) Chemical substances and significant...generically as substituted benzotriazole derivatives (PMNs P-93-374 and...
40 CFR 721.10672 - Sodium olefin sulfonate derivative (generic).
Code of Federal Regulations, 2014 CFR
2014-07-01
...2014-07-01 false Sodium olefin sulfonate derivative (generic). 721.10672 Section...721.10672 Sodium olefin sulfonate derivative (generic). (a) Chemical substances...generically as sodium olefin sulfonate derivative (PMNs P-09-447 and...
40 CFR 721.9079 - Dihydro quinacridone derivative (generic).
Code of Federal Regulations, 2013 CFR
2013-07-01
...2013-07-01 false Dihydro quinacridone derivative (generic). 721.9079 Section... § 721.9079 Dihydro quinacridone derivative (generic). (a) Chemical substance...identified generically as dihydro quinacridone derivative (PMN P-01-397) is subject...
18 CFR 367.2440 - Account 244, Derivative instrument liabilities.
Code of Federal Regulations, 2014 CFR
2014-04-01
...2014-04-01 false Account 244, Derivative instrument liabilities. 367.2440...Liabilities § 367.2440 Account 244, Derivative instrument liabilities. This account...the change in the fair value of all derivative instrument liabilities not...
40 CFR 721.10172 - Alkylamide derivative (generic).
Code of Federal Regulations, 2010 CFR
2010-07-01
... 2010-07-01 false Alkylamide derivative (generic). 721.10172 Section...Substances § 721.10172 Alkylamide derivative (generic). (a) Chemical substance...identified generically as alkylamide derivative (PMN P-03-633) is subject...
17 CFR 240.16a-4 - Derivative securities.
Code of Federal Regulations, 2013 CFR
2013-04-01
...2013-04-01 2013-04-01 false Derivative securities. 240.16a-4 ...Securities Dealers § 240.16a-4 Derivative securities. (a) For purposes of section 16 of the Act, both derivative securities and the...
40 CFR 721.9740 - Brominated triazine derivative.
Code of Federal Regulations, 2012 CFR
2012-07-01
...2012-07-01 false Brominated triazine derivative. 721.9740 Section 721.9740... § 721.9740 Brominated triazine derivative. (a) Chemical substance and significant...generically as a brominated triazine derivative (PMN P-91-403) is subject...
76 FR 51878 - Modifications of Certain Derivative Contracts; Correction
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-19
...1545-BK14 Modifications of Certain Derivative Contracts; Correction AGENCY: Internal...a transfer or assignment of certain derivative contracts does not result in an exchange...1001-4T Modifications of certain derivative contracts...
18 CFR 367.2440 - Account 244, Derivative instrument liabilities.
Code of Federal Regulations, 2012 CFR
2012-04-01
...2012-04-01 false Account 244, Derivative instrument liabilities. 367.2440...Liabilities § 367.2440 Account 244, Derivative instrument liabilities. This account...the change in the fair value of all derivative instrument liabilities not...
12 CFR 217.34 - OTC derivative contracts.
Code of Federal Regulations, 2014 CFR
2014-01-01
...2014-01-01 2014-01-01 false OTC derivative contracts. 217.34 Section 217...General Credit Risk § 217.34 OTC derivative contracts. (a) Exposure amount —(1) Single OTC derivative contract. Except as modified...
40 CFR 721.10172 - Alkylamide derivative (generic).
Code of Federal Regulations, 2012 CFR
2012-07-01
... 2012-07-01 false Alkylamide derivative (generic). 721.10172 Section...Substances § 721.10172 Alkylamide derivative (generic). (a) Chemical substance...identified generically as alkylamide derivative (PMN P-03-633) is subject...
32 CFR 2400.14 - Use of derivative classification.
Code of Federal Regulations, 2010 CFR
2010-07-01
...2010-07-01 2010-07-01 false Use of derivative classification. 2400.14 Section...TECHNOLOGY POLICY INFORMATION SECURITY PROGRAM Derivative Classification § 2400.14 Use of derivative classification. (a)...
17 CFR 240.16a-4 - Derivative securities.
Code of Federal Regulations, 2012 CFR
2012-04-01
...2012-04-01 2012-04-01 false Derivative securities. 240.16a-4 ...Securities Dealers § 240.16a-4 Derivative securities. (a) For purposes of section 16 of the Act, both derivative securities and the...
14 CFR 1203.500 - Use of derivative classification.
Code of Federal Regulations, 2014 CFR
2014-01-01
...2014-01-01 2014-01-01 false Use of derivative classification. 1203.500 Section...ADMINISTRATION INFORMATION SECURITY PROGRAM Derivative Classification § 1203.500 Use of derivative classification. (a)...
75 FR 78185 - Information Management Requirements for Derivatives Clearing Organizations
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-15
...Information Management Requirements for Derivatives Clearing Organizations AGENCY: Commodity...implement certain core principles for derivatives clearing organizations (DCOs) as amended...execution requirements on standardized derivative products; (3) creating...
40 CFR 721.646 - Aminofluoran derivative (generic name).
Code of Federal Regulations, 2012 CFR
2012-07-01
...2012-07-01 false Aminofluoran derivative (generic name). 721.646 Section...Substances § 721.646 Aminofluoran derivative (generic name). (a) Chemical...identified generically as aminofluoran derivative (PMN P-95-512) is subject...
40 CFR 721.10368 - Triphenodioxazine derivatives (generic).
Code of Federal Regulations, 2012 CFR
2012-07-01
...2012-07-01 false Triphenodioxazine derivatives (generic). 721.10368 Section... § 721.10368 Triphenodioxazine derivatives (generic). (a) Chemical substance...identified generically as triphenodioxazine derivatives (PMN P-10-84) is subject...
14 CFR 1203.501 - Applying derivative classification markings.
Code of Federal Regulations, 2012 CFR
2012-01-01
...2012-01-01 2012-01-01 false Applying derivative classification markings. 1203.501...ADMINISTRATION INFORMATION SECURITY PROGRAM Derivative Classification § 1203.501 Applying derivative classification markings. Persons...
14 CFR 1203.501 - Applying derivative classification markings.
Code of Federal Regulations, 2014 CFR
2014-01-01
...2014-01-01 2014-01-01 false Applying derivative classification markings. 1203.501...ADMINISTRATION INFORMATION SECURITY PROGRAM Derivative Classification § 1203.501 Applying derivative classification markings. Persons...
76 FR 43892 - Modifications of Certain Derivative Contracts
Federal Register 2010, 2011, 2012, 2013, 2014
2011-07-22
...1545-BK14 Modifications of Certain Derivative Contracts AGENCY: Internal Revenue...a transfer or assignment of certain derivative contracts does not result in an exchange...necessitate the movement of entire books of derivative contracts. In particular, there...
18 CFR 367.1750 - Account 175, Derivative instrument assets.
Code of Federal Regulations, 2010 CFR
2010-04-01
...2010-04-01 false Account 175, Derivative instrument assets. 367.1750...Assets § 367.1750 Account 175, Derivative instrument assets. This account must include the amounts paid for derivative instruments, and the change...
40 CFR 721.9740 - Brominated triazine derivative.
Code of Federal Regulations, 2011 CFR
2011-07-01
...2011-07-01 false Brominated triazine derivative. 721.9740 Section 721.9740... § 721.9740 Brominated triazine derivative. (a) Chemical substance and significant...generically as a brominated triazine derivative (PMN P-91-403) is subject...
14 CFR 1203.501 - Applying derivative classification markings.
Code of Federal Regulations, 2013 CFR
2013-01-01
...2013-01-01 2013-01-01 false Applying derivative classification markings. 1203.501...ADMINISTRATION INFORMATION SECURITY PROGRAM Derivative Classification § 1203.501 Applying derivative classification markings. Persons...
12 CFR 324.34 - OTC derivative contracts.
Code of Federal Regulations, 2014 CFR
2014-01-01
...2014-01-01 2014-01-01 false OTC derivative contracts. 324.34 Section 324...General Credit Risk § 324.34 OTC derivative contracts. (a) Exposure amount —(1) Single OTC derivative contract. Except as modified...
17 CFR 240.16a-4 - Derivative securities.
Code of Federal Regulations, 2011 CFR
2011-04-01
...2011-04-01 2011-04-01 false Derivative securities. 240.16a-4 ...Securities Dealers § 240.16a-4 Derivative securities. (a) For purposes of section 16 of the Act, both derivative securities and the...
40 CFR 721.2025 - Substituted phenylimino carbamate derivative.
Code of Federal Regulations, 2013 CFR
2013-07-01
... Substituted phenylimino carbamate derivative. 721.2025 Section 721.2025... Substituted phenylimino carbamate derivative. (a) Chemical substance and significant...as a substituted phenylimino carbamate derivative (PMN P-91-487) is subject...
17 CFR 240.16a-4 - Derivative securities.
Code of Federal Regulations, 2010 CFR
2010-04-01
...2010-04-01 2010-04-01 false Derivative securities. 240.16a-4 ...Securities Dealers § 240.16a-4 Derivative securities. (a) For purposes of section 16 of the Act, both derivative securities and the...
40 CFR 721.10330 - Pyrazolone derivative (generic).
Code of Federal Regulations, 2012 CFR
2012-07-01
... 2012-07-01 false Pyrazolone derivative (generic). 721.10330 Section...Substances § 721.10330 Pyrazolone derivative (generic). (a) Chemical substance...identified generically as pyrazolone derivative (PMN P-03-722) is subject...
14 CFR 1203.501 - Applying derivative classification markings.
Code of Federal Regulations, 2010 CFR
2010-01-01
...2010-01-01 2010-01-01 false Applying derivative classification markings. 1203.501...ADMINISTRATION INFORMATION SECURITY PROGRAM Derivative Classification § 1203.501 Applying derivative classification markings. Persons...
Introduction Aliphatic polyesters derived from renewable
Introduction Aliphatic polyesters derived from renewable resources are of increasing interest of these polyesters are already commercially produced in bacteria under nutrient-limited conditions; however of polyesters by ring-opening polymerization. For example, -valerolactone can be obtained in high yield from low
Derivation of the Ideal Gas Law
ERIC Educational Resources Information Center
Laugier, Alexander; Garai, Jozsef
2007-01-01
Undergraduate and graduate physics and chemistry books usually state that combining the gas laws results in the ideal gas law. Leaving the derivation to the students implies that this should be a simple task, most likely a substitution. Boyle's law, Charles's law, and the Avogadro's principle are given under certain conditions; therefore, direct…
Biofuels and bio-products derived from
Ginzel, Matthew
NEED Biofuels and bio- products derived from lignocellulosic biomass (plant materials) are part improve the energy and carbon efficiencies of biofuels production from a barrel of biomass using chemical and thermal catalytic mechanisms. The Center for Direct Catalytic Conversion of Biomass to Biofuels IMPACT
Effects of artemisinin derivatives on malaria transmissibility
R. N Price; F Nosten; C Luxemburger; F. O ter Kuile; L Paiphun; T Chongsuphajaisiddhi; N. J White
1996-01-01
SummaryBackground On the western border of Thailand the efficacy of mefloquine in the treatment of falciparum malaria has declined while gametocyte carriage rates have increased, which suggests increased transmissibility of these resistant infections. We compared the following antimalarial drugs in relation to subsequent Plasmodium falciparum gametocyte carriage: mefloquine, halofantrine, quinine, and the artemisinin derivatives.Methods Between 1990 and 1995 we assessed
CORRESPONDENCE Brain-Derived Neurotrophic Factor, Serotonin
Kalueff, Allan V.
on the role of BDNF in depression, with both antidepressant and pro- depressant effects described (seeCORRESPONDENCE Brain-Derived Neurotrophic Factor, Serotonin Transporter, and Depression: Comment) have recently been implicated in depression (Caspi et al. 2003; Kaufman et al. 2004) and depression
Cellulose Derivatives for Water Repellent Properties
Technology Transfer Automated Retrieval System (TEKTRAN)
In this poster presentation, we will discuss the synthesis and structural characterizations of nitro-benzyl cellulose (1), amino-benzyl cellulose (2) and pentafluoro –benzyl cellulose (3). All cellulose derivatives are synthesized by etherification process in lithium chloride/N,N-dimethylacetamide h...
Another derivation of the geometrical KPZ relations
Francois David; Michel Bauer
2008-10-16
We give a physicist's derivation of the geometrical (in the spirit of Duplantier-Sheffield) KPZ relations, via heat kernel methods. It gives a covariant way to define neighborhoods of fractals in 2d quantum gravity, and shows that these relations are in the realm of conformal field theory.
Curcumin derivatives as HIV-1 protease inhibitors
Sui, Z.; Li, J.; Craik, C.S.; Ortiz de Montellano, P.R. [Univ. of California, San Francisco, CA (United States)
1993-12-31
Curcumin, a non-toxic natural compound from Curcuma longa, has been found to be an HIV-1 protease inhibitor. Some of its derivatives were synthesized and their inhibitory activity against the HIV-1 protease was tested. Curcumin analogues containing boron enhanced the inhibitory activity. At least of the the synthesized compounds irreversibly inhibits the HIV-1 protease.
Feature Ranking Derived from Data Mining Process
Ales Pilny; Pavel Kord
Most common feature ranking methods are based on the sta- tistical approach. This paper compare several statistical methods with new method for feature ranking derived from data mining process. This method ranks features depending on percentage of child units that sur- vived the selection process. A child unit is a processing element trans- forming the parent input features to the
Paper Chromatography of Nicotinic Acid Derivatives
E. Kodicek; K. K. Reddi
1951-01-01
LEIFER et al.1 have reported the paper chromatography of nicotinic acid with the use of microbiological assay. While our work was in progress, Huebner2 described a spot test for detection of some pyridine derivatives. The present work describes sensitive qualitative techniques developed in this Laboratory for the detection of tertiary and quaternary pyridinium compounds. The laborious procedure involved in the
Simple Derivation of the Lindblad Equation
ERIC Educational Resources Information Center
Pearle, Philip
2012-01-01
The Lindblad equation is an evolution equation for the density matrix in quantum theory. It is the general linear, Markovian, form which ensures that the density matrix is Hermitian, trace 1, positive and completely positive. Some elementary examples of the Lindblad equation are given. The derivation of the Lindblad equation presented here is…
Derivation of physically motivated wind speed scales
Nikolai Dotzek
2009-01-01
A class of new wind speed scales is proposed in which the relevant scaling factors are derived from physical quantities like mass flux density, energy density (pressure), or energy flux density. Hence, they are called Energy- or E-scales, and can be applied to wind speeds of any intensity. It is shown that the Mach scale is a special case of
Photodynamic therapy photosensitizers derived from chlorophyll a
NASA Astrophysics Data System (ADS)
Bonnett, Raymond; Benzie, Robin; Grahn, Michael F.; Salgado, A.; Valles, Maria A.
1994-03-01
A series of hydroxychlorins and another of (omega) -carboxyalkyloxy derivatives have been prepared from chlorophyll (alpha) , and their potential photosensitizing ability for the photodynamic therapy of cancer tested in vitro by the MTT assay. The results show that the monohydroxychlorin VI, because of its high photoactivity and its low dark toxicity, is the most promising compound of these series.
DERIVED DEMAND FOR WHEAT BY CLASS
Justin J. Terry; Thomas L. Marsh
2000-01-01
To quantify price responsiveness and economic substitutability among wheat classes, derived demand functions were specified from a normalized quadratic profit function. Own-price and cross-price elasticities were estimated for hard red winter, hard red spring, soft wheat (combined red and white), and durum wheat. In general, soft wheat varieties were less responsive to their own price than were hard wheat varieties.
UNCORRECTED 2 Deriving daily evapotranspiration from remotely
Paris-Sud XI, Université de
UNCORRECTED PROOF 2 Deriving daily evapotranspiration from remotely 3 sensed instantaneous; accepted 24 February 2008 KEYWORDS Q4 Evapotranspiration; Evaporative fraction; Diurnal course; Available evapotranspiration from remotely ..., J. Hydrol. (2008), doi:10.1016/j.jhydrol.2008.02.016 ird-00388433,version1
High speed point derivative microseismic detector
Uhl, James Eugene (Albuquerque, NM); Warpinski, Norman Raymond (Albuquerque, NM); Whetten, Ernest Blayne (Albuquerque, NM)
1998-01-01
A high speed microseismic event detector constructed in accordance with the present invention uses a point derivative comb to quickly and accurately detect microseismic events. Compressional and shear waves impinging upon microseismic receiver stations disposed to collect waves are converted into digital data and analyzed using a point derivative comb including assurance of quiet periods prior to declaration of microseismic events. If a sufficient number of quiet periods have passed, the square of a two point derivative of the incoming digital signal is compared to a trip level threshold exceeding the determined noise level to declare a valid trial event. The squaring of the derivative emphasizes the differences between noise and signal, and the valid event is preferably declared when the trip threshold has been exceeded over a temporal comb width to realize a comb over a given time period. Once a trial event has been declared, the event is verified through a spatial comb, which applies the temporal event comb to additional stations. The detector according to the present invention quickly and accurately detects initial compressional waves indicative of a microseismic event which typically exceed the ambient cultural noise level by a small amount, and distinguishes the waves from subsequent larger amplitude shear waves.
High speed point derivative microseismic detector
Uhl, J.E.; Warpinski, N.R.; Whetten, E.B.
1998-06-30
A high speed microseismic event detector constructed in accordance with the present invention uses a point derivative comb to quickly and accurately detect microseismic events. Compressional and shear waves impinging upon microseismic receiver stations disposed to collect waves are converted into digital data and analyzed using a point derivative comb including assurance of quiet periods prior to declaration of microseismic events. If a sufficient number of quiet periods have passed, the square of a two point derivative of the incoming digital signal is compared to a trip level threshold exceeding the determined noise level to declare a valid trial event. The squaring of the derivative emphasizes the differences between noise and signal, and the valid event is preferably declared when the trip threshold has been exceeded over a temporal comb width to realize a comb over a given time period. Once a trial event has been declared, the event is verified through a spatial comb, which applies the temporal event comb to additional stations. The detector according to the present invention quickly and accurately detects initial compressional waves indicative of a microseismic event which typically exceed the ambient cultural noise level by a small amount, and distinguishes the waves from subsequent larger amplitude shear waves. 9 figs.
Two-point derivative dispersion relations
NASA Astrophysics Data System (ADS)
Ferreira, Erasmo; Sesma, Javier
2013-03-01
A new derivation is given for the representation, under certain conditions, of the integral dispersion relations of scattering theory through local forms. The resulting expressions have been obtained through an independent procedure to construct the real part and consist of new mathematical structures of double infinite summations of derivatives. In this new form the derivatives are calculated at the generic value of the energy E and separately at the reference point E = m that is the lower limit of the integration. This new form may be more interesting in certain circumstances and directly shows the origin of the difficulties in convergence that were present in the old truncated forms called standard-derivative dispersion relations (DDR). For all cases in which the reductions of the double to single sums were obtained in our previous work, leading to explicit demonstration of convergence, these new expressions are seen to be identical to the previous ones. We present, as a glossary, the most simplified explicit results for the DDR's in the cases of imaginary amplitudes of forms (E/m)?[ln (E/m)]n that cover the cases of practical interest in particle physics phenomenology at high energies. We explicitly study the expressions for the cases with ? negative odd integers, that require identification of cancelation of singularities, and provide the corresponding final results.
Deriving Tests From Software Architectures ITT Industries
Offutt, Jeff
Deriving Tests From Software Architectures Zhenyi Jin ITT Industries Advanced Engineering Software Engineering Research Lab George Mason University Fairfax, VA 22030-4444 USA www.ise.gmu.edu/faculty/ofut/ ofut@ise.gmu.edu The Twelfth IEEE InternationalSymposium on Software Re- liability Engineering (ISSRE
UNDERSTANDING, DERIVING, AND COMPUTING BUFFER CAPACITY
Derivation and systematic calculation of buffer capacity is a topic that seems often to be neglected in chemistry courses and given minimal treatment in most texts. However, buffer capacity is very important in the chemistry of natural waters and potable water. It affects corro...
Deriving a Pedagogy of Educational Foundations
ERIC Educational Resources Information Center
Fenstermacher, Gary D.
2007-01-01
This sixth and last paper in the series describes four elements believed to be crucial to a high quality pedagogy for educational foundations. These four elements are derived from a close reading of the previous papers. The work of Osguthorpe, Sanger, Haniford, and Mucher, four of the authors in this series, is cited as both a source for these…
EQUIVARIANT DERIVED CATEGORIES, ZUCKERMAN FUNCTORS AND LOCALIZATION
Milicic, Dragan
EQUIVARIANT DERIVED CATEGORIES, ZUCKERMAN FUNCTORS AND LOCALIZATION Dragan MiliciÂ´c and Pavle- resentation theory: Zuckerman's cohomological construction and the localiza- tion theory of Bernstein of the Zuckerman construction. Let g be a com- plex semisimple Lie algebra and K a complex algebraic group
Tectonic plate motions derived from Lageos
R. Biancale; A. Cazenave; K. Dominh
1991-01-01
Five years of laser data (1984-88) between the Lageos satellite and the ground station network based on precise monthly computations of the Lageos satellite are analyzed to recover tectonic motions affecting the stations. A global inversion over this period provides solutions for absolute velocities in latitude and longitude of a selected subset of 14 stations. Relative horizontal velocities are derived
Singlet exciton fission in a hexacene derivative.
Lee, Jiye; Bruzek, Matthew J; Thompson, Nicholas J; Sfeir, Matthew Y; Anthony, John E; Baldo, Marc A
2013-03-13
Hexacene, an acene with six benzene rings, is notable for its exceptionally small triplet energy, around one third of the singlet energy. Herein, singlet fission, i.e., conversion of a singlet exciton into two triplets, is demonstrated in a thin film of hexacene derivative, employing both transient absorption spectroscopy and magnetic field effects on photocurrent. PMID:23293054
Deriving simulators for hybrid Chi models
D. A. van Beek; K. L. Man; M. A. Reniers; J. E. Rooda; R. R. H. Schiffelers
2006-01-01
The hybrid Chi language is a formalism for modeling, simulation and verification of hybrid systems. The formal semantics of hybrid Chi allows the definition of provably correct implementations for simulation, verification and real-time control. This paper discusses the principles of deriving an implementation for simulation and verification directly from the semantics, and presents an implementation based on a symbolic solver.
Azulene Derivatives as Plant Growth Regulators
Robert M. Muir
1961-01-01
AMONG the many hundreds of compounds examined for effects in promoting cell elongation, very few having activity do not have a ring structure possessing aromatic character1. Thus it is logical to look for activity in compounds having `non-classical' aromatic rings such as derivatives of azulene and ferrocene. The azulene compounds are of particular significance since this ring system occurs frequently
Ecosystem Services Derived from Headwater Catchments
We used data from the USEPA?s wadeable streams assessment (WSA), US Forest Service?s forest inventory and analysis (FIA), and select USFS experimental forests (EF) to investigate potential ecosystems services derived from headwater catchments. C, N, and P inputs to these catchmen...
Derivation of road network from land parcels
Jiantong Zhang; Yueqin Zhu; Jukka Krisp; Liqiu Meng
2010-01-01
This paper presents an adapted algorithm to derive road network from land parcels based on skeleton operator. The spaces among the neighboring parcels are assumed to be occupied by roads. These potential roads are decomposed and approximated to generate road centerlines. The proposed algorithm minimizes unwanted artifacts by computing the negative minima curvature of the boundary. The algorithm includes three
Dynamic derivative UV spectroscopy for combustion monitoring
NASA Astrophysics Data System (ADS)
Sassenscheid, Karsten; Klocke, Ulrich; Marb, C.; Riedel, H.; Schmidtke, Gerhard; Tacke, Maurus
1999-01-01
Derivative UV-absorption spectroscopy is a powerful spectroscopic technique for multicomponent gas analysis, particularly in combustion and process controlling applications. It offers enhanced selectivity and sensitivity compared to conventional techniques. We here report on a test of a special system with optical derivative generation in a waste incineration plant. Gas analysis is performed by transmission spectroscopy. A deuterium lamp is used as UV- source. Spectroscopic filtering is provided by a special grating monochromator. The grating is mounted on a galvanometer scanner, thus allowing a computer controlled wavelength scan and modulation. Signal analysis is performed with lock-in amplifier. The is from of detection for derivative spectra with a movable optical component is the origin of the term DYnamic Derivative Spectroscopy (DDS). The performance of this spectroscopic technique was demonstrated in a measurement campaign at a municipal solid waste incineration plant. The sensitivity for relevant gases is blow ppm level with an optical cell length of 10cm. The basics of the DDS and its performance will be explained, and data on NO, SO2 and NO2 will be reported.
Convenient syntheses of isomaltose derivatives from amygdalin
Martin Chwalek; Karen Plé
2004-01-01
The isomaltose trichloroacetimidate 7 was synthesized in five steps from d-amygdalin. The key step in this series of reactions was the acid catalyzed rearrangement of the inter-glycosydic bond to give the thermodynamically more stable ?-anomer. The reaction was also applied to different di-, tri-, and tetrasaccharide derivatives of amygdalin giving the corresponding rearrangement products.
Derivatives and the Graphs of Functions Microworld
NSDL National Science Digital Library
James White
2004-11-01
The purpose of this Microworld is to experiment with some of the general applications of the derivative to the study of the behavior of functions. This includes their critical behavior, their local extrema, regions of monotonicity (increasing or decreasing), and their inflection points.
Deriving Production Rules for Incremental View Maintenance
Stefano Ceri; Jennifer Widom
1991-01-01
. It is widely recognized that production rules indatabase systems can be used to automatically maintain deriveddata such as views. However, writing a correct set ofrules for efficiently maintaining a given view can be a difficultand ad-hoc process. We provide a facility whereby a userdefines a view as an SQL select expression, from which thesystem automatically derives set-oriented production rulesthat
78 FR 76787 - Position Limits for Derivatives
Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-19
...FUTURES TRADING COMMISSION 17 CFR Parts 1, 15, 17, 19, 32, 37, 38, 140 and 150 RIN 3038-AD99 Position Limits for Derivatives Correction In proposed rule document 2013-27200 appearing on pages 75679 through 75842 in the issue of Thursday,...
Antimicrobial activity of resin acid derivatives
Sonia Savluchinske-Feio; Maria João Marcelo Curto; Bárbara Gigante; J. Carlos Roseiro
2006-01-01
The wide potential of resin acids as bioactive agents gave rise to a growing effort in the search for new applications of the natural forms and their derivatives. In some of these compounds, the antimicrobial activity is associated to the presence in the molecules of functional groups such as the hydroxyl, aldehyde, and ketone or to their cis or trans
Meteorological Products Derived from MSG Imagery
Kuligowski, Bob
Meteorological Products Derived from MSG Imagery MPEF and SAFs #12;Slide 2 SEVIRI Instrument June 2005 #12;Slide 3 The MSG MPEF: Meteorological Products Extraction Facility MPEF is part of the Meteorological Products provided by the MSG system The list of products to be extracted from the MSG imagery has
A new derivation of the APES filter
Petre Stoica; Hongbin Li; Jian Li
1999-01-01
We introduce a novel design criterion for data-dependent narrowband filters that are of interest in temporal or spatial spectral analysis applications. The solution to the design problem considered is shown to coincide with the previously introduced amplitude and phase estimation (APES) filter. The new derivation of APES in this article sheds more light on the properties of APES and provides
Communication The monitoring of bovine pregnancies derived
Paris-Sud XI, UniversitÃ© de
/ embryo transfer / in vitro fertilization / nuclear transfer Reprod. Nutr. Dev. 42 (2002) 613Â624 613Communication The monitoring of bovine pregnancies derived from transfer of in vitro produced are associated with bovine pregnancies obtained from in vitro produced embryos. This thus requires for a more
Photocontrolled chignolin-derived ?-hairpin peptidomimetics.
Podewin, T; Rampp, M S; Turkanovic, I; Karaghiosoff, K L; Zinth, W; Hoffmann-Röder, A
2015-03-01
The synthesis of novel, chignolin-derived peptides comprising the azobenzene photoswitch [3-(3-aminomethyl)phenylazo]phenylacetic acid (AMPP) is reported. Reversible photoswitching behavior led to folding into ?-hairpin-like structures, as unequivocally demonstrated by CD, FT-IR and NMR spectroscopy. PMID:25622946
Entropy theory for derivation of infiltration equations
NASA Astrophysics Data System (ADS)
Singh, Vijay P.
2010-03-01
An entropy theory is formulated for modeling the potential rate of infiltration in unsaturated soils. The theory is composed of six parts: (1) Shannon entropy, (2) principle of maximum entropy (POME), (3) specification of information on infiltration in terms of constraints, (4) maximization of entropy in accordance with POME, (5) derivation of the probability distribution of infiltration, and (6) derivation of infiltration equations. The theory is illustrated with the derivation of six infiltration equations commonly used in hydrology, watershed management, and agricultural irrigation, including Horton, Kostiakov, Philip two-term, Green-Ampt, Overton, and Holtan equations, and the determination of the least biased probability distributions of these infiltration equations and their entropies. The theory leads to the expression of parameters of the derived infiltration equations in terms of measurable quantities (or information), called constraints, and in this sense these equations are rendered nonparametric. Furthermore, parameters of these infiltration equations can be expressed in terms of three measurable quantities: initial infiltration, steady infiltration, and soil moisture retention capacity. Using parameters so obtained, infiltration rates are computed using these six infiltration equations and are compared with field experimental observations reported in the hydrologic literature as well as the rates computed using parameters of these equations obtained by calibration. It is found that infiltration parameter values yielded by the entropy theory are good approximations.
Rheological properties of sulfoacetate derivatives of cellulose.
Chauvelon, Gaëlle; Doublier, Jean-Louis; Buléon, Alain; Thibault, Jean-François; Saulnier, Luc
2003-04-01
Water-soluble cellulose acetate sulfate derivatives (CAS) have been prepared through chemical reaction involving sulfuric acid as a catalyst. These CAS have been obtained from cellulosic materials of different origins (pure cellulose, wheat bran, maize bran) and their rheological behavior in salt-free aqueous solution has been estimated in dilute and semi-dilute regime using dynamic viscoelastic and viscosity measurements. Influence of concentration, temperature of solubilization and temperature of measurement has been investigated. Weak gel-like properties were exhibited at elevated concentration (typically above 7-8 g/L). These systems also exhibited thixotropic properties: the structure was partly broken down upon shearing and recovered at rest. They also displayed thermoreversibility with large hysteresis, the melting temperature being approximately 15 degrees C higher than the temperature at which gelation took place. These overall observations clearly indicate that these distinctive properties arise from intermolecular association of the macromolecular chains of the cellulose derivative. PMID:12668095
Tooth-derived bone graft material
Kim, Young-Kyun; Lee, Junho; Kim, Kyung-Wook; Murata, Masaru; Akazawa, Toshiyuki; Mitsugi, Masaharu
2013-01-01
With successful extraction of growth factors and bone morphogenic proteins (BMPs) from mammalian teeth, many researchers have supported development of a bone substitute using tooth-derived substances. Some studies have also expanded the potential use of teeth as a carrier for growth factors and stem cells. A broad overview of the published findings with regard to tooth-derived regenerative tissue engineering technique is outlined. Considering more than 100 published papers, our team has developed the protocols and techniques for processing of bone graft material using extracted teeth. Based on current studies and studies that will be needed in the future, we can anticipate development of scaffolds, homogenous and xenogenous tooth bone grafts, and dental restorative materials using extracted teeth. PMID:24471027
A derivative standard for polarimeter calibration
Mulhollan, G.; Clendenin, J.; Saez, P. [and others
1996-10-01
A long-standing problem in polarized electron physics is the lack of a traceable standard for calibrating electron spin polarimeters. While several polarimeters are absolutely calibrated to better than 2%, the typical instrument has an inherent accuracy no better than 10%. This variability among polarimeters makes it difficult to compare advances in polarized electron sources between laboratories. The authors have undertaken an effort to establish 100 nm thick molecular beam epitaxy grown GaAs(110) as a material which may be used as a derivative standard for calibrating systems possessing a solid state polarized electron source. The near-bandgap spin polarization of photoelectrons emitted from this material has been characterized for a variety of conditions and several laboratories which possess well calibrated polarimeters have measured the photoelectron polarization of cathodes cut from a common wafer. Despite instrumentation differences, the spread in the measurements is sufficiently small that this material may be used as a derivative calibration standard.
Bacterial degradation of chlorophenols and their derivatives
2014-01-01
Chlorophenols (CPs) and their derivatives are persistent environmental pollutants which are used in the manufacture of dyes, drugs, pesticides and other industrial products. CPs, which include monochlorophenols, polychlorophenols, chloronitrophenols, chloroaminophenols and chloromethylphenols, are highly toxic to living beings due to their carcinogenic, mutagenic and cytotoxic properties. Several physico-chemical and biological methods have been used for removal of CPs from the environment. Bacterial degradation has been considered a cost-effective and eco-friendly method of removing CPs from the environment. Several bacteria that use CPs as their sole carbon and energy sources have been isolated and characterized. Additionally, the metabolic pathways for degradation of CPs have been studied in bacteria and the genes and enzymes involved in the degradation of various CPs have been identified and characterized. This review describes the biochemical and genetic basis of the degradation of CPs and their derivatives. PMID:24589366
Unit Costs for Lunar-Derived Propellants
NASA Astrophysics Data System (ADS)
Blair, Brad R.
2004-02-01
The estimated propellant production cost per metric ton will be derived and presented for solar system transportation waypoints. Background on recent and ongoing space resource propellant supply models will be presented, with a review of architectural assumptions, costs and expected markets. Integrated economic and engineering models (Duke et al., 2003; Duke, Blair and Diaz, 2002; Lamassoure et al. 2003; and Blair et al., 2002) estimate production costs, expected productivity of the mining and processing system, reusable transportation element behavior, fuel depot activity and revenues based on projected market conditions. Results of these economic models are used to derive total and marginal unit costs for propellant at fuel depot facilities for the purpose of facilitating the commercial development of space and to aid program and logistic planning for human space exploration missions.
Derived Patterns in Binocular Rivalry Networks
2013-01-01
Binocular rivalry is the alternation in visual perception that can occur when the two eyes are presented with different images. Wilson proposed a class of neuronal network models that generalize rivalry to multiple competing patterns. The networks are assumed to have learned several patterns, and rivalry is identified with time periodic states that have periods of dominance of different patterns. Here, we show that these networks can also support patterns that were not learned, which we call derived. This is important because there is evidence for perception of derived patterns in the binocular rivalry experiments of Kovács, Papathomas, Yang, and Fehér. We construct modified Wilson networks for these experiments and use symmetry breaking to make predictions regarding states that a subject might perceive. Specifically, we modify the networks to include lateral coupling, which is inspired by the known structure of the primary visual cortex. The modified network models make expected the surprising outcomes observed in these experiments. PMID:23657206
Derivation of evolutionary payoffs from observable behavior
Feigel, Alexander; Engel, Assaf
2008-01-01
Interpretation of animal behavior, especially as cooperative or selfish, is a challenge for evolutionary theory. Strategy of a competition should follow from corresponding Darwinian payoffs for the available behavioral options. The payoffs and decision making processes, however, are difficult to observe and quantify. Here we present a general method for the derivation of evolutionary payoffs from observable statistics of interactions. The method is applied to combat of male bowl and doily spiders, to predator inspection by sticklebacks and to territorial defense by lions, demonstrating animal behavior as a new type of game theoretical equilibrium. Games animals play may be derived unequivocally from their observable behavior, the reconstruction, however, can be subjected to fundamental limitations due to our inability to observe all information exchange mechanisms (communication).
Phytotoxic and antimicrobial activities of catechin derivatives.
Veluri, Ravikanth; Weir, Tiffany L; Bais, Harsh Pal; Stermitz, Frank R; Vivanco, Jorge M
2004-03-10
(+/-)-Catechin is a potent phytotoxin, with the phytotoxicity due entirely to the (-)-catechin enantiomer. (+)-Catechin, but not the (-)-enantiomer, has antibacterial and antifungal activities. Tetramethoxy, pentaacetoxy, and cyclic derivatives of (+/-)-catechin retained phytotoxicity. The results indicate that antioxidant properties of catechins are not a determining factor for phytotoxicity. A similar conclusion was reached for the antimicrobial properties. Centaurea maculosa (spotted knapweed) exudes (+/-)-catechin from its roots, but the flavanol is not re-absorbed and hence the weed is not affected. The much less polar tetramethoxy derivative may, however, be absorbed and hence be able to cause toxicity. Because of the combination of phytotoxicity and antimicrobial activity, (+/-)-catechin could be a useful natural herbicide and antimicrobial. PMID:14995101
Hydrocarbon and nonhydrocarbon derivatives of cyclopropane
NASA Technical Reports Server (NTRS)
Slabey, Vernon A; Wise, Paul H; Gibbons, Louis C
1953-01-01
The methods used to prepare and purify 19 hydrocarbon derivatives of cyclopropane are discussed. Of these hydrocarbons, 13 were synthesized for the first time. In addition to the hydrocarbons, six cyclopropylcarbinols, five alkyl cyclopropyl ketones, three cyclopropyl chlorides, and one cyclopropanedicarboxylate were prepared as synthesis intermediates. The melting points, boiling points, refractive indices, densities, and, in some instances, heats of combustion of both the hydrocarbon and nonhydrocarbon derivatives of cyclopropane were determined. These data and the infrared spectrum of each of the 34 cyclopropane compounds are presented in this report. The infrared absorption bands characteristic of the cyclopropyl ring are discussed, and some observations are made on the contribution of the cyclopropyl ring to the molecular refractions of cyclopropane compounds.
Triamine chelants, their derivatives, complexes and conjugates
Troutner, D.E.; John, C.S.; Pillai, M.R.A.
1995-03-07
A group of functionalized triamine chelants and their derivatives that form complexes with radioactive metal ions are disclosed. The complexes can be covalently attached to a protein or an antibody or antibody fragment and used for therapeutic and/or diagnostic purposes. The chelants are of the formula, as shown in the accompanying diagrams, wherein n, m, R, R{sup 1}, R{sup 2} and L are defined in the specification.
Triamine chelants, their derivatives, complexes and conjugates
Troutner, David E. (Phoenixville, PA); John, Christy S. (Gaithersburg, MD); Pillai, Maroor R. A. (Vashi, IN)
1995-01-01
A group of functionalized triamine chelants and their derivatives that form complexes with radioactive metal ions are disclosed. The complexes can be covalently attached to a protein or an antibody or antibody fragment and used for therapeutic and/or diagnostic purposes. The chelants are of the formula: ##STR1## wherein n, m, R, R.sup.1, R.sup.2 and L are defined in the specification.
Eosinophil Secretion of Granule-Derived Cytokines
Spencer, Lisa A.; Bonjour, Kennedy; Melo, Rossana C. N.; Weller, Peter F.
2014-01-01
Eosinophils are tissue-dwelling leukocytes, present in the thymus, and gastrointestinal and genitourinary tracts of healthy individuals at baseline, and recruited, often in large numbers, to allergic inflammatory foci and sites of active tissue repair. The biological significance of eosinophils is vast and varied. In health, eosinophils support uterine and mammary gland development, and maintain bone marrow plasma cells and adipose tissue alternatively activated macrophages, while in response to tissue insult eosinophils function as inflammatory effector cells, and, in the wake of an inflammatory response, promote tissue regeneration, and wound healing. One common mechanism driving many of the diverse eosinophil functions is the regulated and differential secretion of a vast array of eosinophil-derived cytokines. Eosinophils are distinguished from most other leukocytes in that many, if not all, of the over three dozen eosinophil-derived cytokines are pre-synthesized and stored within intracellular granules, poised for very rapid, stimulus-induced secretion. Eosinophils engaged in cytokine secretion in situ utilize distinct pathways of cytokine release that include classical exocytosis, whereby granules themselves fuse with the plasma membrane and release their entire contents extracellularly; piecemeal degranulation, whereby granule-derived cytokines are selectively mobilized into vesicles that emerge from granules, traverse the cytoplasm and fuse with the plasma membrane to release discrete packets of cytokines; and eosinophil cytolysis, whereby intact granules are extruded from eosinophils, and deposited within tissues. In this latter scenario, extracellular granules can themselves function as stimulus-responsive secretory-competent organelles within the tissue. Here, we review the distinctive processes of differential secretion of eosinophil granule-derived cytokines. PMID:25386174
Chemically Derived, Ultrasmooth Graphene Nanoribbon Semiconductors
Xiaolin Li; Xinran Wang; Li Zhang; Sangwon Lee; Hongjie Dai
2008-01-01
We developed a chemical route to produce graphene nanoribbons (GNR) with width below 10 nanometers, as well as single ribbons with varying widths along their lengths or containing lattice-defined graphene junctions for potential molecular electronics. The GNRs were solution-phase derived, stably suspended in solvents with noncovalent polymer functionalization, and exhibited ultrasmooth edges with possibly well-defined zigzag or armchair-edge structures. Electrical
KPZ formula derived from Liouville heat kernel
Nathanaël Berestycki; Christophe Garban; Rémi Rhodes; Vincent Vargas
2014-06-27
In this paper, we establish the Knizhnik--Polyakov--Zamolodchikov (KPZ) formula of Liouville quantum gravity, using the heat kernel of Liouville Brownian motion. This derivation of the KPZ formula was first suggested by F. David and M. Bauer in order to get a geometrically more intrinsic way of measuring the dimension of sets in Liouville quantum gravity. We also provide a careful study of the (no)-doubling behaviour of the Liouville measures in the appendix, which is of independent interest.
A 2-arylbenzofuran derivative from Hopea mengarawan.
Juliawaty, Lia D; Sahidin; Hakim, Euis H; Achmad, Sjamsul A; Syah, Yana M; Latip, Jalifah; Said, Ikram M
2009-07-01
A new 2-arylbenzofuran derivative (diptoindonesin G) (1), along with nine known oligostilbenes, have been isolated and identified from the acetone extract of the tree bark of Hopea mengarawan. The structures of these compounds were determined based on spectroscopic data, including 2D NMR and HREIMS spectra. On cytotoxic evaluation of the isolated compounds against murin leukemia P-388 cells, compound 1 was the strongest in inhibiting the growth of the cells. PMID:19731600
Canonical structure of higher derivative theories
Eran Avraham; Ram Brustein
2014-06-19
The canonical structure of theories whose Lagrangian contains higher powers of time derivatives is often obscured by the nonlinear relationship between the velocities and momenta. We use the Dirac formalism and define a generalized Legendre transform to overcome some of the difficulties associated with inverting the relation between velocities and momenta. We are then able to define a standard single valued symplectic structure on phase space and a compatible single valued Hamiltonian. We demonstrate the application of our formalism in several examples.
Branching problems of Zuckerman derived functor modules
Toshiyuki Kobayashi
2011-08-17
We discuss recent developments on branching problems of irreducible unitary representations $\\pi$ of real reductive groups when restricted to reductive subgroups. Highlighting the case where the underlying $(g,K)$-modules of $\\pi$ are isomorphic to Zuckerman's derived functor modules $A_q(\\lambda)$, we show various and rich features of branching laws such as infinite multiplicities, irreducible restrictions, multiplicity-free restrictions, and discrete decomposable restrictions. We also formulate a number of conjectures.
Branching problems of Zuckerman's derived functor modules
Kobayashi, Toshiyuki
2011-01-01
We discuss recent developments on branching problems of irreducible unitary representations $\\pi$ of real reductive groups when restricted to reductive subgroups. Highlighting the case where the underlying $(g,K)$-modules of $\\pi$ are isomorphic to Zuckerman's derived functor modules $A_q(\\lambda)$, we show various and rich features of branching laws such as infinite multiplicities, irreducible restrictions, multiplicity-free restrictions, and discrete decomposable restrictions. We also formulate a number of conjectures.
BIOMASS DERIVED, CARBON SEQUESTERING, DESIGNED FERTILIZERS
Kimberly A. Magrini-Bair; Stefan Czernik; Heidi M. Pilath; Robert J. Evans; Pin Ching Maness; Joel Leventhal
2009-01-01
This work explores the hypothesis that functionalized biomass-derived chars (charcoal) can act as fertilizer- delivering, carbon-sequestering soil amendments. A naturally occurring precedent for this approach is based on recent results that clearly link increased soil productivity with charcoal-like Terra Preta deposits, which are characterized by enhanced microbial and fungal activity and are found in both temperate and tropical climates. In
Ferric iron in mantle-derived garnets
Robert W. Luth; David Virgo; Francis R. Boyd; Bernard J. Wood
1990-01-01
The oxidation state of a mantle assemblage may be defined by heterogeneous reactions between oxygen and iron-bearing minerals. In spinel lherzolites, the presence of Fe3+ in spinel allows use of the assemblage olivine-orthopyroxene-spinel to define fO2 at fixed T and P. As a first step towards establishing an analogous reaction for garnet lherzolites, garnets from mantle-derived xenoliths from South Africa
An assessment of derived flood frequency distributions
Raines, Timothy Howard
1991-01-01
were compared with those computed from the historic streamflow recorded at each site using the Log-Pearson Type III extreme value distribution. The HEC-I rainfaH- runoff model was also used to simulate peak discharges for a specified recurtence.... 2 . 6 DERIVED MODEL DESCRIPTIONS Marginal PDFs of Total Rainfall Intensity and Duration. . . Infiltration Models Joint PDF of Excess Rainfall Intensity and Duration . . . . . . . Watershed Response Models. CDF of Peak Direct Runoff...
Basement Membrane Derived Inhibitors of Angiogenesis
Michael B. Duncan; Raghu Kalluri
Blood vessel growth during development and disease is likely governed by the balance between pro- and antiangiogenic factors.\\u000a Numerous reports have focused on the important role of various growth factors during angiogenesis. Peptide fragments derived\\u000a from basement membranes constitute a relatively new and expanding class of antiangiogenic factors with a potential for clinical\\u000a relevance. These factors have been studied in
Myeloid derived suppressor cells in human diseases
Tim F. Greten; Michael P. Manns; Firouzeh Korangy
2011-01-01
Myeloid derived suppressor cells (MDSC) have been described as a heterogeneous cell population with potent immune suppressor function in mice. Limited data are available on MDSC in human diseases. Interpretation of these data is complicated by the fact that different markers have been used to analyze human MDSC subtypes in various clinical settings. Human MDSC are CD11b+, CD33+, HLA-DRneg\\/low and
A New Derivation of the APES Filter
Petre Stoica; Hongbin Li; Jian Li; Senior Member
1999-01-01
We introduce a novel design criterion for datadependent narrowband filters that are of interest in temporal or spatial spectral analysis applications. The solution to the design problem considered is shown to coincide with the recently introduced amplitude and phase estimation (APES) filter. The new derivation of APES in this note sheds more light on the properties of APES and provides some intuitive explanation of the performance superiority of the APES filter over the Capon filter.
The Fréchet Derivatives of Electromagnetic Induction
Alan D. Chave
1984-01-01
netic induction are examined in detail. The response functions for both modes are shown to be Fr6chet differentiable in an L 2 norm for general conductivity structures and arbitrary source frequency-wavenumber morphology. Perturbation forms of the modal Green functions are derived and used to examine the Fr6chet kernels for a seafloor controlled source and a Kelvin wave model. In both
Satellite Derived Tropical Ocean Surface Currents
NSDL National Science Digital Library
Users can view imagery and read about tropical Pacific near-surface currents. The analysis is based on satellite altimeter- and scatterometer-derived sea level wind data. Materials presented here include monthly surface current maps, beginning with October 1992 and ending with the latest available satellite data (usually about one month delay). Links to related sites, a publications list, and a presentations list are also inlcuded.
Trioxsalen derivatives with lipoxygenase inhibitory activity.
Hadjipavlou-Litina, D; E Bariamis, S; Militsopoulou, M; Athanassopoulos, C M; Papaioannou, D
2009-12-01
Trioxsalen (TRX) is a 4,5',8-trimethylated psoralen analog presenting interesting biological activities when irradiated with UVA light. A series of TRX derivatives, which where obtained by its chemical modification and incorporation of a variety of unsaturated functions at position 4' of the psoralen ring-system, were evaluated for their antioxidant activity and their inhibitory activity on soybean lipoxygenase (LOX) and lipid peroxidation. The reducing properties of the compounds were evaluated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay and found to be very low, in the range 0-14%, with the exception of the hydroxamic acid 6 which showed almost identical activity to BHT. TRX derivative 3 significantly inhibited LOX, with IC(50) 9.4 muM. With the exception of TRX, all tested analogs inhibited lipid peroxidation in the range of 35-91%. The most potent compound, namely TRX derivative 3, was studied for its anti-inflammatory activity in vivo on rat paw edema induced by carrageenan, and was found to be of almost identical activity to indomethacin. The results of the biological tests are discussed in terms of structural characteristics. PMID:19912068
Antimalarial activity of new acridinone derivatives.
Fernández-Calienes, Aymé; Pellón, Rolando; Docampo, Maite; Fascio, Mirta; D'Accorso, Norma; Maes, Louis; Mendiola, Judith; Monzote, Lianet; Gille, Lars; Rojas, Lázara
2011-06-01
Malaria is one of the major threats concerning world public health. Resistance to the current antimalarial drugs has led to searches for new antimalarial compounds. Acridinone derivatives have recently demonstrated to be active against malaria parasite. We focused our attention on synthesized new acridinone derivatives, some of them resulting with high antiviral and trypanocidal activity. In this study new derivatives of 10-alyl-, 10-(3-methyl-2-butenyl)- and 10-(1,2-propadienyl)-9(10H)-acridinone were evaluated for their antimalarial activity against Plasmodium falciparum. To assess the selectivity, cytotoxicity was assessed in parallel against human MRC-5 cells. Inhibition of ?-hematin formation was determined using a spectrophotometric assay. Mitochondrial bc(1) complexes were isolated from yeast and bovine heart cells to test acridinone inhibitory activity. This study resulted in the identification of three compounds with submicromolar efficacy against P. falciparum and without cytotoxic effects on human cellular line. One compound, IIa (1-fluoro-10-(3-methyl-2-butenyl)-9(10H)-acridinone), can be classified as hit for antimalarial drug development exhibiting IC(50) less than 0.2 ?g/mL with SI greater than 100. In molecular tests, no relevant inhibitory activity was obtained for our compounds. The mechanism of acridinones antimalarial action remains unclear. PMID:21641752
Neutrophil-Derived Cytokines: Facts Beyond Expression
Tecchio, Cristina; Micheletti, Alessandra; Cassatella, Marco A.
2014-01-01
Polymorphonuclear neutrophils, besides their involvement in primary defense against infections – mainly through phagocytosis, generation of toxic molecules, release of enzymes, and formation of extracellular traps – are also becoming increasingly important for their contribution to the fine regulation in development of inflammatory and immune responses. These latter functions of neutrophils occur, in part, via their de novo production and release of a large variety of cytokines, including chemotactic cytokines (chemokines). Accordingly, the improvement in technologies for molecular and functional cell analysis, along with concomitant advances in cell purification techniques, have allowed the identification of a continuously growing list of neutrophil-derived cytokines, as well as the characterization of their biological implications in vitro and/or in vivo. This short review summarizes crucial concepts regarding the modalities of expression, release, and regulation of neutrophil-derived cytokines. It also highlights examples illustrating the potential implications of neutrophil-derived cytokines according to recent observations made in humans and/or in experimental animal models. PMID:25374568
Maternally Transmitted and Food-Derived Glycotoxins
Mericq, Veronica; Piccardo, Cecilia; Cai, Weijing; Chen, Xue; Zhu, Li; Striker, Gary E.; Vlassara, Helen; Uribarri, Jaime
2010-01-01
OBJECTIVE Proinflammatory advanced glycation end products (AGEs) found in thermally processed foods correlate with serum AGEs (sAGEs) and promote type 1 and type 2 diabetes in mice. Herein we assess the relationship of maternal blood and food AGEs to circulating glycoxidants, inflammatory markers, and insulin levels in infants up to age 1 year. RESEARCH DESIGN AND METHODS AGEs (N?-carboxymethyllysine [CML] and methylglyoxal derivatives) were tested in sera of healthy mothers in labor (n = 60), their infants, and infant foods. Plasma 8-isoprostane, fasting glucose, insulin, leptin, and adiponectin levels were assessed in 12-month-old infants. RESULTS Significant correlations were found between newborn and maternal serum CML (sCML) (r = 0.734, P = 0.001) serum methylglyoxal derivatives (sMGs) (r = 0.593, P = 0.001), and 8-isoprostanes (r = 0.644, P = 0.001). Infant adiponectin at 12 months negatively correlated with maternal sCML (r = ?0.467, P = 0.011), whereas high maternal sMGs predicted higher infant insulin or homeostasis model assessment (P = 0.027). Infant sAGEs significantly increased with the initiation of processed infant food intake, raising daily AGE consumption by ?7.5-fold in year 1. CONCLUSIONS Maternal blood and food-derived AGEs prematurely raise AGEs in children to adult norms, preconditioning them to abnormally high oxidant stress and inflammation and thus possibly to early onset of disease, such as diabetes. PMID:20628088
Perturbative unitarity of Higgs derivative interactions
NASA Astrophysics Data System (ADS)
Kikuta, Yohei; Yamamoto, Yasuhiro
2013-05-01
We study the perturbative unitarity bound given by dimension six derivative interactions consisting of Higgs doublets. These interactions emerge from kinetic terms of composite Higgs models or integrating out heavy particles that interact with Higgs doublets. They lead to new phenomena beyond the Standard Model. One of characteristic contributions from derivative interactions appear in vector boson scattering processes. Longitudinal modes of massive vector bosons can be regarded as Nambu Goldstone bosons eaten by each vector field. Since their effects become larger and larger as the collision energy of vector bosons increases, vector boson scattering processes become important in the high energy region around the TeV scale. On the other hand, in such a high energy region, we have to take into account the unitarity of amplitudes. We have obtained the unitarity condition in terms of the parameter included in the effective Lagrangian for one Higgs doublet models. Applying it to some models, we have found that contributions of derivative interactions are not so large enough to clearly discriminate them from the Standard Model ones. We also study the unitarity bound in two Higgs doublet models. Because they are too complex to obtain it in the general effective Lagrangian, we have calculated it in explicit models. These analyses tell that the perturbative unitarity bounds are highly model dependent.
Hydrodynamic Nambu brackets derived by geometric constraints
NASA Astrophysics Data System (ADS)
Blender, Richard; Badin, Gualtiero
2015-03-01
A geometric approach to derive the Nambu brackets for ideal two-dimensional (2D) hydrodynamics is suggested. The derivation is based on two-forms with vanishing integrals in a periodic domain, and with resulting dynamics constrained by an orthogonality condition. As a result, 2D hydrodynamics with vorticity as dynamic variable emerges as a generic model, with conservation laws which can be interpreted as enstrophy and energy functionals. Generalized forms like surface quasi-geostrophy and fractional Poisson equations for the stream-function are also included as results from the derivation. The formalism is extended to a hydrodynamic system coupled to a second degree of freedom, with the Rayleigh–Bénard convection as an example. This system is reformulated in terms of constitutive conservation laws with two additive brackets which represent individual processes: a first representing inviscid 2D hydrodynamics, and a second representing the coupling between hydrodynamics and thermodynamics. The results can be used for the formulation of conservative numerical algorithms that can be employed, for example, for the study of fronts and singularities.
Adult-derived pluripotent stem cells.
Faulkner, Stuart D; Vawda, Reaz; Fehlings, Michael G
2014-01-01
The global incidence of spinal cord injury (SCI) is 15-40 cases per million people, with the socioeconomic and healthcare costs amounting to nearly $10 billion per annum in the USA alone. Despite substantial advances in medical care and surgical technology, many patients with SCI still experience significant long-term neurologic disability. Cellular transplantation offers a promising therapy to address the multifactorial nature of SCI in both the subacute and chronic phase of the injury to promote central nervous system repair and regeneration and to augment existing therapies. Adult-derived stem cells are the least ethically challenging stem cells but, until recently, a major hurdle has been inducing pluripotency to generate the required neural lineages. Improved generation and transfection techniques, combined with positive experimental outcomes in SCI models, suggest that adult-derived induced pluripotent stem cells could be a genuine alternative to embryonic stem cells for clinical treatments. For translation from bench to bedside, the efficacy of induced pluripotent stem cell-derived neural stem and progenitor cells in suitable SCI models needs to be validated further and backed up with rigorous early-stage clinical trials. PMID:23948650
Advances in temperature derivative control and calorimetry
NASA Astrophysics Data System (ADS)
Hemmerich, J. L.; Loos, J.-C.; Miller, A.; Milverton, P.
1996-11-01
Temperature stabilization by inertial feedback control has proven a powerful tool to create the ultrastable environment essential for high resolution calorimetry. A thermally insulated mass, connected to a base through Seebeck effect sensors (thermopiles) is used as a reference to control the base temperature. The thermopile signal is proportional to both the heat capacity of the reference mass and the derivative ?? of the base temperature ?. Using vacuum insulation and bismuth telluride thermopiles, we designed and tested temperature derivative sensors (TDSs) with sensitivities up to 3300 V s K-1. Standard industrial controllers with approximately ±1 ?V input noise and stability, permit control of temperature derivatives to ±3×10-10 K s-1. Single-cup thermoelectric calorimeters coupled to the TDS-controlled base permitted measurement of heat flow from samples in a power range from 3 ?W to 10 W with high accuracy (±100 ppm), resolution (±0.2 ?W), and reproducibility (±1 ?W). The design of two instruments is described in detail. Their performance is demonstrated on a variety of measurements, e.g., the determination of sample heat capacities with temperature ramp rates ??=±5×10-6 K s-1, the half-life of a 3 g tritium sample in a uranium getter bed, the decay heat of depleted uranium, and the heat evolution of epoxy resin.
Derivation of naïve human embryonic stem cells
Ware, Carol B.; Nelson, Angelique M.; Mecham, Brigham; Hesson, Jennifer; Zhou, Wenyu; Jonlin, Erica C.; Jimenez-Caliani, Antonio J.; Deng, Xinxian; Cavanaugh, Christopher; Cook, Savannah; Tesar, Paul J.; Okada, Jeffrey; Margaretha, Lilyana; Sperber, Henrik; Choi, Michael; Blau, C. Anthony; Treuting, Piper M.; Hawkins, R. David; Cirulli, Vincenzo; Ruohola-Baker, Hannele
2014-01-01
The naïve pluripotent state has been shown in mice to lead to broad and more robust developmental potential relative to primed mouse epiblast cells. The human naïve ES cell state has eluded derivation without the use of transgenes, and forced expression of OCT4, KLF4, and KLF2 allows maintenance of human cells in a naïve state [Hanna J, et al. (2010) Proc Natl Acad Sci USA 107(20):9222–9227]. We describe two routes to generate nontransgenic naïve human ES cells (hESCs). The first is by reverse toggling of preexisting primed hESC lines by preculture in the histone deacetylase inhibitors butyrate and suberoylanilide hydroxamic acid, followed by culture in MEK/ERK and GSK3 inhibitors (2i) with FGF2. The second route is by direct derivation from a human embryo in 2i with FGF2. We show that human naïve cells meet mouse criteria for the naïve state by growth characteristics, antibody labeling profile, gene expression, X-inactivation profile, mitochondrial morphology, microRNA profile and development in the context of teratomas. hESCs can exist in a naïve state without the need for transgenes. Direct derivation is an elusive, but attainable, process, leading to cells at the earliest stage of in vitro pluripotency described for humans. Reverse toggling of primed cells to naïve is efficient and reproducible. PMID:24623855
Affinity of guanosine derivatives for polycytidylate revisited
NASA Technical Reports Server (NTRS)
Kanavarioti, A.; Hurley, T. B.; Baird, E. E.
1995-01-01
Evidence is presented for complexation of guanosine 5'-monophosphate 2-methylimidazolide (2-MeImpG) with polycytidylate (poly(C)) at pH 8.0 and 23 degrees C in the presence of 1.0 M NaCl2 and 0.2 M MgCl2 in water. The association of 2-MeImpG with poly(C) was investigated using UV-vis spectroscopy as well as by monitoring the kinetics of the nucleophilic substitution reaction of the imidazole moiety by amines. The results of both methods are consistent with moderately strong poly(C) 2-MeImpG complexation and the spectrophotometric measurements allowed the construction of a binding isotherm with a concentration of 2-MeImpG equal to 5.55 +/- 0.15 mM at half occupancy. UV spectroscopy was employed to establish the binding of other guanosine derivatives on poly(C). These derivatives are guanosine 5'-monophosphate (5'GMP), guanosine 5'-monophosphate imidazolide (ImpG), and guanosine 5'-monophosphate morpholidate (morpG). Within experimental error these guanosine derivatives exhibit the same affinity for poly(C) as 2-MeImpG.
Immunofluorescence in Cells Derived from Burkitt's Lymphoma
Henle, Gertrude; Henle, Werner
1966-01-01
Henle, Gertrude (Children's Hospital of Philadelphia, Philadelphia, Pa.), and Werner Henle. Immunofluorescence in cells derived from Burkitt's lymphoma. J. Bacteriol. 91:1248–1256. 1966.—Indirect immunofluorescence tests led to the brilliant staining of a small proportion of the cells in five different cultures derived from Burkitt's (African) lymphomas. The reaction was not restricted to the 17 sera from cases of this disease but extended to many sera from American individuals, whether healthy donors or patients suffering from a variety of illnesses. The incidence of positive sera increased with age from about 30% in childhood to > 90% in adults. Fluorescein-isothiocyanate-conjugated human ?-globulins were suitable for direct staining of the same proportion of cells. The stained cells appeared to be in varying stages of degeneration, but cultural conditions leading to an increase in the cellular death rates failed to result in a rise in fluorescent cells. Several observations suggest that the stainable cells might be those which are seen to harbor virus particles under the electron microscope. Two cell lines derived from leukemic patients in this country also contained a small fraction of stainable cells but two others, and numerous primary human leukocyte cultures, gave consistently negative results. Attempts to relate the staining to known viral antigens have failed to implicate herpes simplex, varicella, cytomegalo, and reo viruses types 1, 2, and 3. The nature of the virus carried by the lymphoma cells as well as of the staining reactions remains to be determined. Images PMID:4160230
Hydroxylated Sclerosporin Derivatives from the Marine-derived Fungus Cadophora malorum†
Almeida, Celso; Eguereva, Ekaterina; Kehraus, Stefan; Siering, Carsten; König, Gabriele M.
2010-01-01
The marine-derived fungus Cadophora malorum was isolated from the green alga Enteromorpha sp. Growth on a biomalt medium supplemented with sea salt yielded an extract from which we have isolated sclerosporin and four new hydroxylated sclerosporin derivatives, namely 15-hydroxysclerosporin (2), 12-hydroxysclerosporin (3), 11-hydroxysclerosporin (4) and 8-hydroxysclerosporin (5). The compounds were evaluated in various biological activity assays. Compound 5 showed a weak fat-accumulation inhibitory activity against 3T3-L1 murine adipocytes. PMID:20052971
Derived equivalences and stable equivalences of Morita type, I
Wei Hu; Changchang Xi
2010-01-01
For self-injective algebras, Rickard proved that each derived equivalence induces a stable equivalence of Morita type. For general algebras, it is unknown when a derived equivalence implies a stable equivalence of Morita type. In this article, we first show that each derived equivalence $F$ between the derived categories of Artin algebras $A$ and $B$ arises naturally as a functor $\\\\bar{F}$
Derived equivalences and stable equivalences of Morita type, I
Wei Hu; Changchang Xi
2008-01-01
For self-injective algebras, Rickard proved that each derived equivalence induces a stable equivalence of Morita type. For general algebras, it is unknown when a derived equivalence implies a stable equivalence of Morita type. In this paper, we first show that each derived equivalence $F$ between the derived categories of Artin algebras $A$ and $B$ arises naturally a functor $\\\\bar{F}$ between
Transformation of spatial and perturbation derivatives of travel time
Cerveny, Vlastislav
Transformation of spatial and perturbation derivatives of travel time at a general interface and perturbation parameters. We derive the explicit equations for transforming these travelÂtime derivatives Hamiltonian function and are applicable to the transformation of travelÂtime derivatives in both isotropic
Derivative-free family of higher order root finding methods
Mohammed A. Hasan
2009-01-01
Most higher order root finding methods require evaluation of a function and\\/or its derivatives at one or multiple points. There are cases where the derivatives of a given function are costly to compute. In this paper, higher order methods which do not require computation of any derivatives are derived. Asymptotic analysis has shown that these methods are approximations of root
Higher-derivative massive actions from dimensional reduction
Euihun Joung; Karapet Mkrtchyan
2012-12-24
A procedure to obtain higher-derivative free massive actions is proposed. It consists in dimensional reduction of conventional two-derivative massless actions, where solutions to constraints bring in higher derivatives. We apply this procedure to derive the arbitrary dimensional generalizations of (linearized) New Massive Gravity and New Topologically Massive Gravity.
Stem cell-derived neurons functionally integrate in
Fortuna, Miguel A.
Stem cell-derived neurons functionally integrate in living mice Neurons derived from stem cells that, after transplantation into living animals, human stem cell-derived neurons can receive neuronal human embryonic stem cell (hESC)-derived neurons engineered to be specifically activated by light
Higher Derivative Correction to the Hawking Flux via Trace Anomaly
Akihide Shirasaka; Tomoyoshi Hirata
2008-04-15
In this paper we derive Hawking radiation of black holes with higher derivative corrections by the method of trace anomaly. Firstly we derive Hawking radiation for general spherical black holes. We introduce a modified tortoise coordinate to it and find the analyticity of the coordinate. Secondly we apply its method to a black hole with a higher derivative correction and derive the Hawking radiation of it. We found that as an ordinary case the flux depends only on the surface gravity.
On the derivative discontinuity in molecular junctions
NASA Astrophysics Data System (ADS)
Stafford, Charles
2012-02-01
Both the wave and particle aspects of the electron play essential roles in transport through single-molecule junctions. The wave character is implicit both in the Landauer formula used to understand nanoscale transport and in the very chemical bonds holding the junction together, while the particle aspect is manifested in phenomena such as Coulomb blockade and shot noise. The dominant computational paradigm for transport in single-molecule junctions involves local or semilocal approximations to density functional theory combined with nonequilibrium Green's functions. This approach does exceptionally well at describing the wave aspect of the electron, but fails to describe the particle aspect---due to the omission of the derivative discontinuity in the exchange-correlation potential that arises in the limit of vanishing lead-molecule coupling. To understand the role of the derivative discontinuity in molecular junctions, we investigated the transport and occupancy of a simple Anderson model of a molecular junction. We showedootnotetextJustin P. Bergfield, Zhenfei Liu, Kieron Burke, Charles A. Stafford, arXiv:1106.3104v2 that the exact single-particle Kohn-Sham potential of density functional theory reproduces the linear-response transport of the Anderson model exactly, despite the lack of a Kondo peak in its spectral function. Using Bethe ansatz techniques, we calculated this potential exactly for all coupling strengths, including the cross-over from mean-field behavior to charge quantization caused by the derivative discontinuity. The implications of our results for more complex molecular junctions will be discussed.
Biologic Rhythms Derived from Siberian Mammoths Hairs
M Spilde; A Lanzirotti; C Qualls; G Phillips; A Ali; L Agenbroad; O Appenzeller
2011-12-31
Hair is preserved for millennia in permafrost; it enshrines a record of biologic rhythms and offers a glimpse at chronobiology as it was in extinct animals. Here we compare biologic rhythms gleaned from mammoth's hairs with those of modern human hair. Four mammoths' hairs came from varying locations in Siberia 4600 km, four time zones, apart ranging in age between 18,000 and 20,000 years before present. We used two contemporaneous human hairs for comparison. Power spectra derived from hydrogen isotope ratios along the length of the hairs gave insight into biologic rhythms, which were different in the mammoths depending on location and differed from humans. Hair growth for mammoths was {approx}31 cms/year and {approx}16 cms/year for humans. Recurrent annual rhythms of slow and fast growth varying from 3.4 weeks/cycles to 8.7 weeks/cycles for slow periods and 1.2 weeks/cycles to 2.2 weeks/cycles for fast periods were identified in mammoth's hairs. The mineral content of mammoth's hairs was measured by electron microprobe analysis (k-ratios), which showed no differences in sulfur amongst the mammoth hairs but significantly more iron then in human hair. The fractal nature of the data derived from the hairs became evident in Mandelbrot sets derived from hydrogen isotope ratios, mineral content and geographic location. Confocal microscopy and scanning electron microscopy showed varied degrees of preservation of the cuticle largely independent of age but not location of the specimens. X-ray fluorescence microprobe and fluorescence computed micro-tomography analyses allowed evaluation of metal distribution and visualization of hollow tubes in the mammoth's hairs. Seasonal variations in iron and copper content combined with spectral analyses gave insights into variation in food intake of the animals. Biologic rhythms gleaned from power spectral plots obtained by modern methods revealed life style and behavior of extinct mega-fauna.
Biologic rhythms derived from Siberian mammoths' hairs.
Spilde, Mike; Lanzirotti, Antonio; Qualls, Clifford; Phillips, Genevieve; Ali, Abdul-Mehdi; Agenbroad, Larry; Appenzeller, Otto
2011-01-01
Hair is preserved for millennia in permafrost; it enshrines a record of biologic rhythms and offers a glimpse at chronobiology as it was in extinct animals. Here we compare biologic rhythms gleaned from mammoth's hairs with those of modern human hair. Four mammoths' hairs came from varying locations in Siberia 4600 km, four time zones, apart ranging in age between 18,000 and 20,000 years before present. We used two contemporaneous human hairs for comparison. Power spectra derived from hydrogen isotope ratios along the length of the hairs gave insight into biologic rhythms, which were different in the mammoths depending on location and differed from humans. Hair growth for mammoths was ?31 cms/year and ?16 cms/year for humans. Recurrent annual rhythms of slow and fast growth varying from 3.4 weeks/cycles to 8.7 weeks/cycles for slow periods and 1.2 weeks/cycles to 2.2 weeks/cycles for fast periods were identified in mammoth's hairs. The mineral content of mammoth's hairs was measured by electron microprobe analysis (k-ratios), which showed no differences in sulfur amongst the mammoth hairs but significantly more iron then in human hair. The fractal nature of the data derived from the hairs became evident in Mandelbrot sets derived from hydrogen isotope ratios, mineral content and geographic location. Confocal microscopy and scanning electron microscopy showed varied degrees of preservation of the cuticle largely independent of age but not location of the specimens. X-ray fluorescence microprobe and fluorescence computed micro-tomography analyses allowed evaluation of metal distribution and visualization of hollow tubes in the mammoth's hairs. Seasonal variations in iron and copper content combined with spectral analyses gave insights into variation in food intake of the animals. Biologic rhythms gleaned from power spectral plots obtained by modern methods revealed life style and behavior of extinct mega-fauna. PMID:21747920
Dietary derived compounds in cancer chemoprevention
Rzeski, Wojciech
2012-01-01
Cancer chemoprevention is defined as the application of natural or synthetic agents to suppress or reverse cancer development and progression. In this field especially diet derived compounds have recently attracted researchers’ attention as potential therapeutics generally exerting low toxicity compared with regular drugs. This review presents a survey of recent findings concerning the most promising dietary chemopreventive agents such as green tea polyphenols (i.e. catechins), long-chain polyunsaturated fatty acids, carotenoids, glucosinolates/isothiocyanates, vitamins (i.e. vitamin D and folate) and minerals (i.e. calcium and selenium). Molecular targets involved in intrinsic pathways affected by these natural compounds are also shortly discussed. PMID:23788916
Derivation of generalized Maxwell velocity slip model
NASA Astrophysics Data System (ADS)
Yang, Qin; Liu, Yulu; Zhang, Haijun; Zuo, Chuncheng
2014-12-01
Based on the conservation of momentum and energy fluxes in the Knudsen layer, a generalized Maxwell velocity slip boundary model is derived in detail using the velocity distribution function from the Grad thirteen moment approximation. The study shows that the generalized Maxwell velocity slip boundary model has the same form as the slip model given by Lockerby. In addition, it is consistent with the typical Maxwell velocity slip model when the temperature gradient along the surface and the normal velocity of gas flow are neglected.
Direct derivation of "mirror" ABJ partition function
Masazumi Honda
2014-04-18
We study the partition function of the three-dimensional N=6 U(N)_k x U(N+M)_{-k} superconformal Chern-Simons matter theory known as the ABJ theory. We prove that the ABJ partition function on S^3 is exactly the same as a formula recently proposed by Awata, Hirano and Shigemori. While this formula was previously obtained by an analytic continuation from the L(2,1) lens space matrix model, we directly derive this by using a generalization of the Cauchy determinant identity. We also give an interpretation for the formula from brane picture.
Deriving time from the geometry of space
James M. Chappell; John G. Hartnett; Nicolangelo Iannella; Derek Abbott
2015-04-08
The Minkowski formulation of special relativity reveals the essential four-dimensional nature of spacetime, consisting of three space and one time dimension. Recognizing its fundamental importance, a variety of arguments have been proposed over the years attempting to derive the Minkowski spacetime structure from fundamental physical principles. In this paper we illustrate how Minkowski spacetime follows naturally from the geometric properties of three dimensional Clifford space modeled with multivectors. This approach also generalizes spacetime to an eight dimensional space as well as doubling the size of the Lorentz group. This description of spacetime also provides a new geometrical interpretation of the nature of time.
Validation of an Experimentally Derived Uncertainty Model
NASA Technical Reports Server (NTRS)
Lim, K. B.; Cox, D. E.; Balas, G. J.; Juang, J.-N.
1996-01-01
The results show that uncertainty models can be obtained directly from system identification data by using a minimum norm model validation approach. The error between the test data and an analytical nominal model is modeled as a combination of unstructured additive and structured input multiplicative uncertainty. Robust controllers which use the experimentally derived uncertainty model show significant stability and performance improvements over controllers designed with assumed ad hoc uncertainty levels. Use of the identified uncertainty model also allowed a strong correlation between design predictions and experimental results.
Quinaldine derivatives: preparation and biological activity.
Jampilek, Josef; Dolezal, Martin; Kunes, Jiri; Buchta, Vladimir; Silva, Luis; Kralova, Katarina
2005-11-01
The series of quinaldine derivatives were prepared, some of them by means of novel synthetic methods. The synthetic approach, analytical and spectroscopic data of all newly synthesized compounds are presented. The prepared compounds were tested for their in vitro antifungal activity as well as for their photosynthesis-inhibiting activity (the inhibition of photosynthetic electron transport in spinach chloroplasts (Spinacia oleracea L.) and the reduction of chlorophyll content in Chlorella vulgaris Beij.). Structure-activity relationships among the chemical structure, the physical properties and the biological activities of the evaluated compounds are discussed in the article. PMID:16787342
[Antidiuretic activity of dithiocarbamic acid derivatives].
Korablec, M V; Evets, M A
1977-01-01
Chemically pure dithiocarbamates, thiuramsulphides and ethylene-bis-dithiocarbamates display a well-marked antidiuretic action. They materially reduce diuresis, natri- and kaliuresis in rats (1/5 LD(50) per 1 kg into the stomach) and in dogs (sodium N, N-diethyl-dithiocarbamate-into renal artery). Without changing the tubular reabsorption DEDTC inhibits the glomerular filtration of the dogs' kidneys. Furosemide (lasix) prevents the development of the an antidiuletic anidiuretic effect and reduction of the sodium and potassium excretion provoked in rats with DEDTC, zinc N, N', N"-tetraethylthiuram-disulphide and ethylene-bis-dithiocarbamate. Furosemide is recommended for the treatment of acute poisonings with dithiocarbaminic acid derivatives. PMID:200467
Time-derivative preconditioning for viscous flows
NASA Technical Reports Server (NTRS)
Choi, Yunho; Merkle, Charles L.
1991-01-01
A time-derivative preconditioning algorithm that is effective over a wide range of flow conditions from inviscid to very diffusive flows and from low speed to supersonic flows was developed. This algorithm uses a viscous set of primary dependent variables to introduce well-conditioned eigenvalues and to avoid having a nonphysical time reversal for viscous flow. The resulting algorithm also provides a mechanism for controlling the inviscid and viscous time step parameters to be of order one for very diffusive flows, thereby ensuring rapid convergence at very viscous flows as well as for inviscid flows. Convergence capabilities are demonstrated through computation of a wide variety of problems.
Synthesis and antitumor activities of glucan derivatives
Yuguo Du; Guofeng Gu; Yuxia Hua; Guohua Wei; Xinshan Ye; Guangli Yu
2004-01-01
A highly efficient and practical method for the preparation of ?-d-Glc-(1?6)-[?-d-Glc-(1?3)]-?-d-Glc-(1?6)-?-d-Glc-(1?6)-[?-d-Glc-(1?3)]-d-Glc-OMe was described. A dendritic nonasaccharide was also synthesized. The antitumor activities of hexasaccharide, the dendrimer, their sulfated derivatives, together with the natural glucan–protein and the corresponding polysaccharide isolated from barmy mycelium of Grifola frondosa, were preliminarily investigated based on Sarcoma-180 studies in mice tests. Our results suggest that the
Antibacterial endiandric acid derivatives from Beilschmiedia anacardioides.
Chouna, Jean Rodolphe; Nkeng-Efouet, Pepin Alango; Lenta, Bruno Ndjakou; Devkota, Krishna Prasad; Neumann, Beate; Stammler, Hans-Georg; Kimbu, Samuel Fon; Sewald, Norbert
2009-03-01
Three endiandric acid derivatives, beilschmiedic acids A, B and C were isolated from the stem bark of Beilschmiedia anacardioides together with the known beta-sitosterol. Their structures were established by means of modern spectroscopic techniques. The relative configuration of compound 1 was determined by single crystal X-ray analysis. The antibacterial activities of compounds A,B,C were evaluated in vitro against five strains of microbes. Compound C showed strong activity against Bacillus subtilis, Micrococcus luteus and Streptococcus faecalis (MICs below 23 microM). This Compound was more active than the reference antibiotic ampicillin against B. subtilis and M. luteus. PMID:19345383
Black Holes in Higher-Derivative Gravity
Lu, H; Pope, C N; Stelle, K S
2015-01-01
Extensions of Einstein gravity with higher-order derivative terms arise in string theory and other effective theories, as well as being of interest in their own right. In this paper we study static black-hole solutions in the example of Einstein gravity with additional quadratic curvature terms. A Lichnerowicz-type theorem simplifies the analysis by establishing that they must have vanishing Ricci scalar curvature. By numerical methods we then demonstrate the existence of further black-hole solutions over and above the Schwarzschild solution. We discuss some of their thermodynamic properties, and show that they obey the first law of thermodynamics.
Adipose derived stem cells and nerve regeneration
Faroni, Alessandro; Smith, Richard JP; Reid, Adam J
2014-01-01
Injuries to peripheral nerves are common and cause life-changing problems for patients alongside high social and health care costs for society. Current clinical treatment of peripheral nerve injuries predominantly relies on sacrificing a section of nerve from elsewhere in the body to provide a graft at the injury site. Much work has been done to develop a bioengineered nerve graft, precluding sacrifice of a functional nerve. Stem cells are prime candidates as accelerators of regeneration in these nerve grafts. This review examines the potential of adipose-derived stem cells to improve nerve repair assisted by bioengineered nerve grafts. PMID:25221589
Derivation of an Applied Nonlinear Schroedinger Equation.
Pitts, Todd Alan; Laine, Mark Richard; Schwarz, Jens; Rambo, Patrick K.; Karelitz, David B.
2015-01-01
We derive from first principles a mathematical physics model useful for understanding nonlinear optical propagation (including filamentation). All assumptions necessary for the development are clearly explained. We include the Kerr effect, Raman scattering, and ionization (as well as linear and nonlinear shock, diffraction and dispersion). We explain the phenomenological sub-models and each assumption required to arrive at a complete and consistent theoretical description. The development includes the relationship between shock and ionization and demonstrates why inclusion of Drude model impedance effects alters the nature of the shock operator. Unclassified Unlimited Release
Black holes with nonminimal derivative coupling
NASA Astrophysics Data System (ADS)
Rinaldi, Massimiliano
2012-10-01
We study the gravitational field equations in the presence of a coupling between the derivative of a massless scalar field and the Einstein tensor. This configuration is motivated by Galileon gravity as it preserves shift invariance in the scalar sector. We analytically obtain solutions with static and spherically symmetric geometry, which also include black holes with a single regular horizon. We examine the thermodynamical properties of these solutions, and we reveal the nonperturbative nature of the coupling constant. We also find a phase transition, similar to the one described by Hawking and Page, which occurs at a critical temperature determined by both the black hole mass and by the strength of the coupling.
Meshram, Jyotsna
2014-01-01
The present work deals with the synthesis and evaluation of biological activities of 4-aminoantipyrine derivatives derived from a three-component Betti reaction. The synthesis was initiated by the condensation of aromatic aldehyde, 4-aminoantipyrine, and 8-hydroxyquinoline in presence of fluorite as catalyst in a simple one-step protocol. The reactions were stirred at room temperature for 10–15?min achieving 92–95% yield. The structures of synthesized derivatives were established on the basis of spectroscopic and elemental analysis. All derivatives 4(a–h) were screened in vivo and in vitro for anti-inflammatory and anthelmintic activity against a reference drug, Diclofenac and Albendazole, respectively. The screening results show that compounds 4c, 4d, 4f, and 4h were found to possess potential anti-inflammatory activity while compounds 4a, 4b, 4e, and 4g are potent anthelmintic agents when compared with reference drugs, respectively. The bioactivity of these derivatives has also been evaluated with respect to Lipinski's rule of five using molinspiration cheminformatics software. PMID:24955256
Quinolines derivatives as novel sunscreening agents.
Polonini, Hudson C; Dias, Rafael M P; Souza, Isabela O; Gonçalves, Karla Mara; Gomes, Tiago B B; Raposo, Nádia R B; da Silva, Adilson David
2013-08-15
Currently, the research and development of sunscreens play an important role on the synthesis of actives that are stable in various kinds of formulations-in addition to their efficiency and broad spectrum of protection against ultraviolet radiation. Our objective here was to synthesize new sunscreening chemical agents using quinoline as a base molecule. Twelve quinoline derivatives were synthesized, four of them novel molecules, and their photoprotective activity was determined in vitro using diffuse transmittance spectrophotometry. We determined their SPF, UVAPF, UVA/UVB ratio, critical wavelength and Boots Star Rating. The quinolines derivatives presented a varied profile of photoprotection, their SPF ranging from 2 to 11 and their UVAPF from 2 to 7. In terms of the critical wavelength, all molecules were considered of broad-spectrum by different classifications. Regarding the Boots Star Rating, one compound received no rating, seven of them received a three stars rating, three received a four stars rating and three were given a five stars rating. The molecules showed in the present work have a wide range of possibilities for creating new sunscreen products, once they have good SPF or UVAPF for single molecules, and they also possess other different qualities that can act synergistically. PMID:23856048
Anionic derivatives of uracil: fragmentation and reactivity.
Cole, Callie A; Wang, Zhe-Chen; Snow, Theodore P; Bierbaum, Veronica M
2014-09-01
Uracil is an essential biomolecule for terrestrial life, yet its prebiotic formation mechanisms have proven elusive for decades. Meteorites have been shown to contain uracil and the interstellar abundance of aromatic species and nitrogen-containing molecules is well established, providing support for uracil's presence in the interstellar medium (ISM). The ion chemistry of uracil may provide clues to its prebiotic synthesis and role in the origin of life. The fragmentation of biomolecules provides valuable insights into their formation. Previous research focused primarily on the fragmentation and reactivity of cations derived from uracil. In this study, we explore deprotonated uracil-5-carboxylic acid and its anionic fragments to elucidate novel reagents of uracil formation and to characterize the reactivity of uracil's anionic derivatives. The structures of these fragments are identified through theoretical calculations, further fragmentation, experimental acidity bracketing, and reactivity with several detected and potential interstellar species (SO2, OCS, CS2, NO, N2O, CO, NH3, O2, and C2H4). Fragmentation is achieved through collision induced dissociation (CID) in a commercial ion trap mass spectrometer, and all reaction rate constants are measured using a modification of this instrument. Experimental data are supported by theoretical calculations at the B3LYP/6-311++G(d,p) level of theory. Lastly, the astrochemical implications of the observed fragmentation and reaction processes are discussed. PMID:25036757
Tulczyjew Triples in Higher Derivative Field Theory
Katarzyna Grabowska; Luca Vitagliano
2015-02-20
The geometrical structure known as Tulczyjew triple has been used with success in analytical mechanics and first order field theory to describe a wide range of physical systems including Lagrangian/Hamiltonian systems with constraints and/or sources, or with singular Lagrangian. Starting from the first principles of the variational calculus we derive Tulczyjew triples for classical field theories of arbitrary high order, i.e. depending on arbitrary high derivatives of the fields. A first triple appears as the result of considering higher order theories as first order ones with configurations being constrained to be holonomic jets. A second triple is obtained after a reduction procedure aimed at getting rid of nonphysical degrees of freedom. This picture we present is fully covariant and complete: it contains both Lagrangian and Hamiltonian formalisms, in particular the Euler-Lagrange equations. Notice that, the required Geometry of jet bundles is affine (as opposed to the linear Geometry of the tangent bundle). Accordingly, the notions of affine duality and affine phase space play a distinguished role in our picture. In particular the Tulczyjew triples in this paper consist of morphisms of double affine-vector bundles which, moreover, preserve suitable presymplectic structures.
Siderophore production by marine-derived fungi
Holinsworth, Brian; Martin, Jessica D.
2009-01-01
Siderophore production by marine-derived fungi has not been extensively explored. Three studies have investigated the ability of marine-derived fungi to produce siderophores in response to iron limitation [(Vala et al. in Indian J Mar Sci 29:339-340, 2000; Can J Microbiol 52:603-607, 2006); Baakza et al. in J Exp Mar Biol Ecol 311:1-9, 2004]. In all, 24 of 28 marine fungal strains were found to secrete hydroxamate or carboxylate siderophores; no evidence was found for production of catecholate siderophores. These studies did not determine the structures of the iron-binding compounds. More recently, a study of the natural products secreted by a marine Penicillium bilaii revealed that this strain produced the rare catecholate siderophore pistillarin when grown under relatively high iron concentrations (Capon et al. J Nat Prod 70:1746-1752, 2007). Additionally, the production of rhizoferrin by a marine isolate of Cunninghamella elegans (ATCC36112) is reported in this manuscript. The current state of knowledge about marine fungal siderophores is reviewed in light of these promising results. PMID:19350395
Developing cell culture-derived pandemic vaccines.
Barrett, P Noel; Portsmouth, Daniel; Ehrlich, Hartmut J
2010-02-01
The growing prospect of avian influenza viruses achieving sustained interhuman transmission, combined with the recent emergence of a novel swine-origin A/H1N1 influenza strain, has brought the issue of influenza vaccine production capacity into sharp focus. It is becoming increasingly clear that traditional egg-based manufacturing processes may be insufficient to meet global vaccine demands in a pandemic situation that is caused by a highly pathogenic influenza virus. This review introduces the concepts of modern, cell culture-derived influenza vaccines and their manufacture, and explains the advantages of these vaccines in terms of both speed and efficiency of production as well as immunogenic efficacy. Vaccine production technologies using the mammalian cell lines Vero, MDCK and PER.C6, as well as the baculovirus/insect cell platform, are described in detail. Clinical data are provided from cell culture-derived vaccines that are at an advanced stage of development, and insights are provided into recent developments in the preclinical evaluation of more experimental technologies. PMID:20140813
Classes of unitarizable derived functor modules
Enright, Thomas J.; Parthasarathy, Rajagopalan; Wallach, Nolan R.; Wolf, Joseph A.
1983-01-01
For a real semisimple Lie group G, the description of the unitary dual remains an elusive question. One of the difficulties has been the lack of technique for constructing unitary representations. Unitary induction from parabolic subgroups of G yields unitary representations by the very definition of these representations. However, not all unitary irreducible representations of G are obtained by this type of induction. In addition, we need derived functor parabolic induction [ef. Vogan, D. (1981) Representations of Real Reductive Lie Groups (Birkhäuser, Boston)] to describe all irreducible representations of G. For this second type of induction, the obvious analogues from parabolic subgroup induction regarding unitarity are false. In this announcement, we describe a setting where derived functor parabolic induction yields unitary representations of G. These results include proofs of unitarity for some of the representations conjectured to be unitary by Vogan and Zuckerman [(1983) Invent. Math., in press] and also proofs of unitarity for some which lie outside the domain described in those conjectures. PMID:16593391
Derive capillary pressure from well logs
Ibrahim, A. (Suez Canal Univ. (Egypt)); Desbrandes, R.; Bassiouni, Z. (Louisiana State Univ., Baton Rouge, LA (United States))
1994-07-01
A new approach has been developed to estimate in-situ capillary pressure and relative permeability characteristics in the transition zone. The technique is based on incorporating petrophysical data measured on core samples with well log analysis. Relative permeability can be determined for both drainage and inhibition conditions using the matched capillary pressure data. A technique has been developed to extrapolate petro-physical data where core data is absent or not representative of in-situ conditions. It is based on using log data to derive a water saturation vs. depth profile in the transition zone of the formation of interest. The log-derived water saturation distribution is then correlated to generalized capillary pressure curves typical of the formation studied. The capillary pressure type curves are generated from available core data and other petrophysical information. Relative permeability curves are then generated using correlations based on Purcell's model. The technique can be used in multi-layered and homogeneous reservoirs provided that one homogeneous layer is at least 20 ft thick.
Synthesis and biological evaluation of loxoprofen derivatives.
Yamakawa, Naoki; Suemasu, Shintaro; Matoyama, Masaaki; Tanaka, Ken-Ichiro; Katsu, Takashi; Miyata, Keishi; Okamoto, Yoshinari; Otsuka, Masami; Mizushima, Tohru
2011-06-01
Non-steroidal anti-inflammatory drugs (NSAIDs) achieve their anti-inflammatory actions through an inhibitory effect on cyclooxygenase (COX). Two COX subtypes, COX-1 and COX-2, are responsible for the majority of COX activity at the gastrointestinal mucosa and in tissues with inflammation, respectively. We previously suggested that both gastric mucosal cell death due to the membrane permeabilization activity of NSAIDs and COX-inhibition at the gastric mucosa are involved in NSAID-induced gastric lesions. We have also reported that loxoprofen has the lowest membrane permeabilization activity among the NSAIDs we tested. In this study, we synthesized a series of loxoprofen derivatives and examined their membrane permeabilization activities and inhibitory effects on COX-1 and COX-2. Among these derivatives, 2-{4'-hydroxy-5-[(2-oxocyclopentyl)methyl]biphenyl-2-yl}propanoate 31 has a specificity for COX-2 over COX-1. Compared to loxoprofen, oral administration of 31 to rats produced fewer gastric lesions but showed an equivalent anti-inflammatory effect. These results suggest that 31 is likely to be a therapeutically beneficial and safer NSAID. PMID:21570308
Siderophore production by marine-derived fungi.
Holinsworth, Brian; Martin, Jessica D
2009-08-01
Siderophore production by marine-derived fungi has not been extensively explored. Three studies have investigated the ability of marine-derived fungi to produce siderophores in response to iron limitation [(Vala et al. in Indian J Mar Sci 29:339-340, 2000; Can J Microbiol 52:603-607, 2006); Baakza et al. in J Exp Mar Biol Ecol 311:1-9, 2004]. In all, 24 of 28 marine fungal strains were found to secrete hydroxamate or carboxylate siderophores; no evidence was found for production of catecholate siderophores. These studies did not determine the structures of the iron-binding compounds. More recently, a study of the natural products secreted by a marine Penicillium bilaii revealed that this strain produced the rare catecholate siderophore pistillarin when grown under relatively high iron concentrations (Capon et al. J Nat Prod 70:1746-1752, 2007). Additionally, the production of rhizoferrin by a marine isolate of Cunninghamella elegans (ATCC36112) is reported in this manuscript. The current state of knowledge about marine fungal siderophores is reviewed in light of these promising results. PMID:19350395
Lipopolythiourea transfecting agents: lysine thiourea derivatives.
Leblond, Jeanne; Mignet, Nathalie; Largeau, Céline; Seguin, Johanne; Scherman, Daniel; Herscovici, Jean
2008-01-01
Synthetic vectors represent an alternative to recombinant viruses for gene transfer. We have recently explored the transfection potential of a class of noncationic lipids bearing thiourea moieties as DNA-associating headgroups. The encouraging results obtained with lipopolythioureas derived from serinol prompted us to further investigate this family of vectors. In the present study, we considered the transfection properties of a series of derivatives based on a different thiourea polar headgroup bearing a lysine scaffold. The synthesis of these compounds could be readily achieved in three steps with good yields. We found that these lipopolythioureas (LPT) might be considered as alternative systems for gene transfection since their activity reached the same magnitude range as that of cationic vectors in the presence of serum. LPT with 14-carbon length chains appeared to be more efficient as a transfecting agent than the ones with shorter chains. Toxicity studies proved that the hydration film method led to particles well tolerated both by the cells in vitro and by the mice in vivo. The ability to induce gene expression in vivo was demonstrated by intratumoral injection. Finally, biodistribution studies showed that the quantity recovered in blood circulation, 2 h after systemic injection, was improved as compared to that in cationic lipids. PMID:18062657
Thermal electron heating rate: A derivation
NASA Technical Reports Server (NTRS)
Hoegy, W. R.
1983-01-01
The thermal electron heating rate is an important heat source term in the ionospheric electron energy balance equation, representing heating by photoelectrons or by precipitating higher energy electrons. A formula for the thermal electron heating rate is derived from the kinetic equation using the electron-electron collision operator as given by the unified theory of Kihara and Aono. This collision operator includes collective interactions to produce a finite collision operator with an exact Coulomb logarithm term. The derived heating rate O(e) is the sum of three terms, O(e) = O(p) + S + O(int), which are respectively: (1) primary electron production term giving the heating from newly created electrons that have not yet suffered collisions with the ambient electrons; (2) a heating term evaluated on the energy surface m(e)/2 = E(T) at the transition between Maxwellian and tail electrons at E(T); and (3) the integral term representing heating of Maxwellian electrons by energetic tail electrons at energies ET. Published ionospheric electron temperature studies used only the integral term O(int) with differing lower integration limits. Use of the incomplete heating rate could lead to erroneous conclusions regarding electron heat balance, since O(e) is greater than O(int) by as much as a factor of two.
Molecular Modeling Optimization of Anticoagulant Pyridine Derivatives
Hernandez Prada, Jose A.; Madden, Sandra L.; Ostrov, David A.; Hernandez, Maria A.
2013-01-01
Intravascular clotting remains a major health problem in the United States, the most prominent being deep vein thrombosis, pulmonary embolism and thromboembolic stroke. Previous reports on the use of pyridine derivatives in cardiovascular drug development encourage us to pursue new types of compounds based on a pyridine scaffold. Eleven pyridine derivatives (oximes, semicarbazones, N-oxides) previously synthesized in our laboratories were tested as anticoagulants on pooled normal plasma using the prothrombin time (PT) protocol. The best anticoagulant within the oxime series was compound AF4, within the oxime N-oxide series was compound AF4-N-Oxide, and within the semicarbazone series, compound MD1-30Y. We also used a molecular modeling approach to guide our efforts, and found that there was good correlation between coagulation data and computational energy scores. Molecular docking was performed to target the active site of thrombin with the DOCK v5.2 package. The results of molecular modeling indicate that improvement in anticoagulant activities can be expected by functionalization at the 3-position of the pyridine ring and by N-oxide formation. Results reported here prove the suitability of DOCK in the lead optimization process. PMID:18372200
The assay of tropane derivatives in formulations by second derivative ultraviolet spectrophotometry.
Hassan, S M; Davidson, A G
1984-01-01
The development of a second order derivative spectrophotometric assay of atropine, hyoscine and benztropine in formulations is described. The assay involves the extraction into 1,2-dichloroethane of the tetraphenylborate salt of the alkaloids precipitated from pH 6 solution by an excess of sodium tetraphenylboron and measurement of the amplitude near 273 nm to its shorter wavelength satellite in the second derivative spectrum. The second derivative amplitude gives a more precise determination of the alkaloids than absorbance. A two-point bracketing standardization of the amplitude is required owing to a small but significant intercept in the calibration data. The procedures are sufficiently sensitive and precise for the batch and unit-dose assay of tablets of atropine sulphate (0.6 mg) hyoscine hydrobromide (0.3 mg) and benztropine mesylate (2 mg), and for the assay of atropine sulphate injection (0.4 mg ml-1) and tincture of belladonna. PMID:6141274