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1.
J Appl Behav Anal ; 53(3): 1559-1578, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32232861

RESUMEN

Recently, researchers have compared the utility of isolated versus synthesized contingencies in functional analysis (FA) methodology (e.g., Fisher et al., 2016; Slaton et al., 2017). A limitation of these studies is that there were other differences across FA methodologies (e.g., design, contingency) that did not allow for isolation of the influence of isolated versus synthesized contingencies. Therefore, the current study compared outcomes of FAs that involved isolated versus synthesized contingencies for problem behavior of 5 children while controlling for these other differences across FAs (Experiment 1). Next, the current study compared the effects of interventions based on the functions identified in the isolated and synthesized contingencies for each participant (Experiment 2). Results indicated isolated contingency FAs produced differentiated responding for 1 or both functions for all 5 participants, and there were little to no differences between treatments informed by isolated and synthesized contingency FAs.


Asunto(s)
Análisis Aplicado de la Conducta , Terapia Conductista , Problema de Conducta , Preescolar , Femenino , Humanos , Masculino
2.
J Appl Behav Anal ; 53(3): 1660-1673, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32130735

RESUMEN

A synchronous-reinforcement schedule is a type of schedule of covariation in which the onset and offset of the reinforcer covaries with the onset and offset of behavior. This study was a proof-of-concept demonstration of the efficacy of synchronous reinforcement for on-task behavior (completing a preacademic skill) and an evaluation of preschoolers' preference for this schedule in comparison to a more traditional schedule of reinforcement. Specifically, we compared the effects of a synchronous-reinforcement schedule to one in which continuous access to stimuli was delivered at the end of the session and yoked to the duration of on-task behavior that occurred during the session (accumulated reinforcement). Results showed the synchronous-reinforcement schedule was more effective for increasing on-task behavior and preferred by most participants.


Asunto(s)
Conducta de Elección , Refuerzo en Psicología , Preescolar , Humanos , Esquema de Refuerzo
3.
J Appl Behav Anal ; 52(1): 84-104, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30246246

RESUMEN

The Good Behavior Game (GBG) is an effective intervention package for decreasing disruptive behavior in various populations and environments. There is, however, limited research evaluating the GBG with preschoolers. Furthermore, few studies have evaluated the effects of components of the GBG, and of those that have, most have done so only after exposure to the GBG package. We evaluated the effects (a) of the GBG on disruptive behavior of preschoolers during group instruction and (b) the major components of the GBG before and after implementation of the GBG package (c) at both the group and individual level. Results suggest that the GBG package was necessary for decreasing disruptive behavior. However, after exposure to the GBG, a response-independent contingency was effective for maintaining low levels of disruptive behavior at both the group and individual level.


Asunto(s)
Terapia Conductista/métodos , Problema de Conducta/psicología , Instituciones Académicas , Preescolar , Femenino , Humanos , Masculino , Estudiantes/psicología
4.
Inorg Chem ; 56(5): 2884-2901, 2017 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-28218526

RESUMEN

A series of monochloride-bridged, dinuclear metallacycles of the general formula [M2(µ-Cl)(µ-L)2](ClO4)3 have been prepared using the third-generation, ditopic bis(pyrazolyl)methane ligands L = m-bis[bis(1-pyrazolyl)methyl]benzene (Lm), M = Cu(II), Zn(II), and L = m-bis[bis(3,5-dimethyl-1-pyrazolyl)methyl]benzene (Lm*), M = Fe(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II). These complexes were synthesized from the direct reactions of M(ClO4)2·6H2O, MCl2, and the ligand, Lm or Lm*, in the appropriate stoichiometric amounts. Three analogous complexes of the formula [M2(µ-Cl)(µ-L)2](BF4)3, L = Lm, M = Cu(II), and L = Lm*, M = Co(II), Cu(II), were prepared from the reaction of [M2(µ-F)(µ-L)2](BF4)3 and (CH3)3SiCl. The bromide-bridged complex [Cu2(µ-Br)(µ-Lm*)2](ClO4)3 was prepared by the first method. Three acyclic complexes, [Co2(µ-Lm)µ-Cl4], [Co2(µ-Lm*)Cl4], and [Co2(µ-Lm*)Br4], were also prepared. The structures of all [M2(µ-X)(µ-L)2]3+ (X = Cl-, Br-) complexes have two ditopic bis(pyrazolyl)methane ligands bridging two metals in a metallacyclic arrangement. The fifth coordination site of the distorted trigonal bipyramidal metal centers is filled by a bridging halide ligand that has an unusual linear or nearly linear M-X-M angle. The NMR spectra of [Zn2(µ-Cl)(µ-Lm*)2](ClO4)3 and especially [Cd2(µ-Cl)(µ-Lm*)2](ClO4)3 demonstrate that the metallacycle structure is maintained in solution. Solid state magnetic susceptibility data for the copper(II) compounds show very strong antiferromagnetic exchange interactions, with -J values of 536 cm-1 for [Cu2(µ-Cl)(µ-Lm)2](ClO4)3·xCH3CN, 720 cm-1 for [Cu2(µ-Cl)(µ-Lm*)2](ClO4)3, and 945 cm-1 for [Cu2(µ-Br)(µ-Lm*)2](ClO4)3·2CH3CN. Smaller but still substantial antiferromagnetic interactions are observed with other first row transition metals, with -J values of 98 cm-1 for [Ni2(µ-Cl)(µ-Lm*)2](ClO4)3, 55 cm-1 for [Co2(µ-Cl)(µ-Lm*)2](ClO4)3, and 34 cm-1 for [Fe2(µ-Cl)(µ-Lm*)2](ClO4)3. EPR spectra of [Cu2(µ-Cl)(µ-Lm*)2](BF4)3 confirm the dz2 ground state of copper(II). In addition, the sign of the zero-field splitting parameter D was determined to be positive for [Cu2(µ-F)(µ-Lm*)2](BF4)3. Electronic spectra of the copper(II) complexes as well as Mössbauer spectra of the iron(II) complexes were also studied in relation with the EPR spectra and magnetic properties, respectively. Density functional theory calculations were performed using ORCA, and exchange integral values were obtained that parallel but are slightly higher than the experimental values by about 30%.

5.
J Fungi (Basel) ; 2(2)2016 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-29376934

RESUMEN

Allergic bronchopulmonary aspergillosis (ABPA), a progressive fungal allergic lung disease, is a common complication of asthma or cystic fibrosis. Although ABPA has been recognized since the 1950s, recent research has underscored the importance of Th2 immune deviation and granulocyte activation in its pathogenesis. There is also strong evidence of widespread under-diagnosis due to the complexity and lack of standardization of diagnostic criteria. Treatment has long focused on downregulation of the inflammatory response with prolonged courses of oral glucocorticosteroids, but more recently concerns with steroid toxicity and availability of new treatment modalities has led to trials of oral azoles, inhaled amphotericin, pulse intravenous steroids, and subcutaneously-injected anti-IgE monoclonal antibody omalizumab, all of which show evidence of efficacy and reduced toxicity.

6.
J Colloid Interface Sci ; 450: 301-309, 2015 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-25837407

RESUMEN

HYPOTHESIS: This work explores arylation of oxidized nanodiamond (OND) and carboxylated nanodiamond (CND) using phenylphosphonate (PPA) to produce PPA-grafted nanodiamond (PPA@ND). The specific hypothesis is that PPA can be readily grafted onto the surfaces of OND and CND particles via the nanodiamonds' reactive oxygen-rich surface functional groups. EXPERIMENTS: This work explores the effect of varying reaction conditions (reactant ratio, heat, sonication) on PPA graft density and grafting mode. The products were characterized by a variety of techniques including: (31)P MAS NMR and FTIR to confirm PPA grafting, XPS to estimate PPA grafted amounts, and TGA to assess thermal stability. The utility of PPA functionalization for improving ND dispersion in organic solvents was evaluated using dynamic light scattering. FINDINGS: The results confirm PPA grafting on both OND and CND, quantify the extent of PPA grafting, and suggest primarily bidentate grafting. For PPA grafting on OND, the grafted amount does not depend on PPA:ND ratio, application of heat, or use of sonication. The grafted amount of PPA on CND was significantly lower than that on OND. TGA data indicates that grafted PPA improves the thermal stability of both OND and CND. The starting OND disperses in water as aggregates with approximately 100 nm particle size. However, PPA-grafted OND does not disperse at all in water: thus grafted PPA changes the ND surface from hydrophilic to hydrophobic. PPA@OND prepared without sonication does not completely disperse in either DMF or toluene. Only PPA@OND prepared with sonication disperses well in these solvents, suggesting that sonication promotes more complete exposure of the ND surface to PPA grafting.

7.
Inorg Chem ; 53(4): 1975-88, 2014 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-24479509

RESUMEN

The reactions of M(ClO4)2·xH2O and the ditopic ligands m-bis[bis(1-pyrazolyl)methyl]benzene (Lm) or m-bis[bis(3,5-dimethyl-1-pyrazolyl)methyl]benzene (Lm*) in the presence of triethylamine lead to the formation of monohydroxide-bridged, dinuclear metallacycles of the formula [M2(µ-OH)(µ-Lm)2](ClO4)3 (M = Fe(II), Co(II), Cu(II)) or [M2(µ-OH)(µ-Lm*)2](ClO4)3 (M = Co(II), Ni(II), Cu(II)). With the exception of the complexes where the ligand is Lm and the metal is copper(II), all of these complexes have distorted trigonal bipyramidal geometry around the metal centers and unusual linear (Lm*) or nearly linear (Lm) M-O-M angles. For the two solvates of [Cu2(µ-OH)(µ-Lm)2](ClO4)3, the Cu-O-Cu angles are significantly bent and the geometry about the metal is distorted square pyramidal. All of the copper(II) complexes have structural distortions expected for the pseudo-Jahn-Teller effect. The two cobalt(II) complexes show moderate antiferromagnetic coupling, -J = 48-56 cm(-1), whereas the copper(II) complexes show very strong antiferromagnetic coupling, -J = 555-808 cm(-1). The largest coupling is observed for [Cu2(µ-OH)(µ-Lm*)2](ClO4)3, the complex with a Cu-O-Cu angle of 180°, such that the exchange interaction is transmitted through the dz(2) and the oxygen s and px orbitals. The interaction decreases, but it is still significant, as the Cu-O-Cu angle decreases and the character of the metal orbital becomes increasingly d(x(2)-y(2)). These intermediate geometries and magnetic interactions lead to spin Hamiltonian parameters for the copper(II) complexes in the EPR spectra that have large E/D ratios and one g matrix component very close to 2. Density functional theory calculations were performed using the hybrid B3LYP functional in association with the TZVPP basis set, resulting in reasonable agreement with the experiments.

8.
Pediatr Pulmonol ; 49(1): 8-14, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23401301

RESUMEN

RATIONALE: Recent observations, especially in adults, suggest that asthma severity may be associated with fungal sensitization. Other studies suggest that some patients with severe asthma and fungal sensitization may benefit from anti-fungal therapy. Currently, the prevalence of fungal sensitization among children with severe asthma is not well characterized. METHODS: We determined prevalence of fungal sensitization among children with moderate to severe persistent asthma and compared clinical characteristics between sensitized and non-sensitized children, including asthma severity, serum immunoglobulin E, and pulmonary function. RESULTS: Of the 64 children enrolled, 25 (39%) had evidence of sensitization to one or more fungi. Nineteen of 25 (76%) children with fungal sensitization were categorized as severe persistent compared to 13 of 39 (33%) children without evidence of fungal sensitization (odds ratio = 6.33, 95% confidence interval 2.04-19.68, P = 0.0014). Of 32 severe persistent asthmatics, 19 (59%) demonstrated evidence of fungal sensitization. Serum immunoglobulin E was significantly higher (P < 0.001), and pulmonary function (including FEV1, FEV1/FVC, and FEF25-75%) significantly lower in the fungal-sensitized patients (P = 0.016, 0.0004, and 0.002, respectively). Bronchial biopsy of sensitized children revealed basement membrane thickening and eosinophil infiltration. CONCLUSIONS: Fungal sensitization in children with persistent asthma is associated with disease severity. Almost 60% of our severe persistent asthma patients had evidence of fungal sensitization and, based on our previous studies, may be potential candidates for anti-fungal therapy.


Asunto(s)
Antígenos Fúngicos/inmunología , Asma/inmunología , Asma/fisiopatología , Inmunización , Adolescente , Broncoscopía , Niño , Preescolar , Femenino , Humanos , Inmunoglobulina E/sangre , Pulmón/fisiopatología , Masculino , Índice de Severidad de la Enfermedad , Adulto Joven
9.
Inorg Chem ; 49(1): 234-42, 2010 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-19961186

RESUMEN

The reaction of 1,2,4,5-tetrakis(bromomethyl)benzene and hexakis(bromomethyl)benzene with the alkoxide of 2,2-bis(1-pyrazolyl)ethanol leads to the synthesis of the new polytopic ligands 1,2,4,5-C(6)H(2)[CH(2)OCH(2)CH(pz)(2)](4) (L(tetra), pz = pyrazolyl ring) and C(6)[CH(2)OCH(2)CH(pz)(2)](6) (L(hexa)). Reactions of these ligands and the appropriate silver(I) salt lead to the preparation of [Ag(2)L(tetra)](BF(4))(2) (1), [Ag(2)L(tetra)](SO(3)CF(3))(2) (2), [Ag(3)L(hexa)](BF(4))(3) (3), and [Ag(3)L(hexa)](ClO(4))(3) (4). The solid-state structures of four different complexes crystallized from solutions of 1 or 2 yield five independent structures of the [Ag(2)L(tetra)](2+) cation, all with similar structures. In all of the structures, two para-oriented pairs of "arms" (-CH(2)OCH(2)CH(pz)(2)) from a single ligand each chelate a silver(I) ion on the opposite sides of the arene ring, forming a double, mononuclear metallacyclic structure of two 17-membered rings connected by the central arene ring. The structures about the silver(I) cations in these complexes are distorted tetrahedral. The flexibility of the ligand leads to two types of arrangements of the linking arms in the five complexes. The central cations of the two L(hexa) complexes also form double, mononuclear metallacycles, but the structures are different from those of the silver complexes of L(tetra) in that both L(hexa) cations contain one para-linked and one meta-linked metallacycle, thus forming a 16- and a 17-membered ring. In addition, the two remaining arms on L(hexa) coordinate with additional silver(I) cations, linking the double, mononuclear metallacycles into a coordination polymer network.

10.
Inorg Chem ; 48(22): 10658-69, 2009 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-19827795

RESUMEN

The reaction of M(BF(4))(2).xH(2)O, where M is Fe, Co, Cu, and Zn, and the ditopic, bis(pyrazolyl)methane ligand m-[CH(pz)(2)](2)C(6)H(4), L(m), where pz is a pyrazolyl ring, yields the monofluoride bridged, binuclear [M(2)(mu-F)(mu-L(m))(2)](BF(4))(3) complexes. In contrast, a similar reaction of L(m) with Ni(BF(4))(2).6H(2)O yields dibridged [Ni(2)(mu-F)(2)(mu-L(m))(2)](BF(4))(2). The solid state structures of seven [M(2)(mu-F)(mu-L(m))(2)](BF(4))(3) complexes show that the divalent metal ion is in a five-coordinate, trigonal bipyramidal, coordination environment with either a linear or nearly linear M-F-M bridging arrangement. NMR results indicate that [Zn(2)(mu-F)(mu-L(m))(2)](BF(4))(3) retains its dimeric structure in solution. The [Ni(2)(mu-F)(2)(mu-L(m))(2)](BF(4))(2) complex has a dibridging fluoride structure that has a six-coordination environment about each nickel(II) ion. In the solid state, the [Fe(2)(mu-F)(mu-L(m))(2)](BF(4))(3) and [Co(2)(mu-F)(mu-L(m))(2)](BF(4))(3) complexes show weak intramolecular antiferromagnetic exchange coupling between the two metal(II) ions with J values of -10.4 and -0.67 cm(-1), respectively; there is no observed long-range magnetic order. Three different solvates of [Cu(2)(mu-F)(mu-L(m))(2)](BF(4))(3) are diamagnetic between 5 and 400 K, thus showing strong antiferromagnetic exchange interactions of -600 cm(-1) or more negative. Mossbauer spectra indicate that [Fe(2)(mu-F)(mu-L(m))(2)](BF(4))(3) exhibits no long-range magnetic order between 4.2 and 295 K and isomer shifts that are consistent with the presence of five-coordinate, high-spin iron(II).

11.
Inorg Chem ; 48(19): 9393-401, 2009 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-19780620

RESUMEN

The complex [Fe{HC(3-Mepz)(2)(5-Mepz)}(2)](BF(4))(2) (pz = pyrazolyl ring) has been prepared by the reaction of HC(3-Mepz)(2)(5-Mepz) with Fe(BF(4))(2) x 6 H(2)O. The solid state structures obtained at 294 and 150 K show a distorted iron(II) octahedral N(6) coordination environment with the largest deviations arising from the restrictions imposed by the chelate rings. At 294 K the complex is predominately high-spin with Fe-N bond distances averaging 2.14 A, distances that are somewhat shorter than expected for a purely high-spin iron(II) complex because of the presence of an admixture of about 80% high-spin and 20% low-spin iron(II). At 294 K the twisting of the pyrazolyl rings from the ideal C(3v) symmetry averages only 2.2 degrees, a much smaller twist than has been observed previously in similar complexes. At 150 K the Fe-N bond distances average 1.99 A, indicative of an almost fully low-spin iron(II) complex; the twist angle is only 1.3 degrees, as expected for a complex with these Fe-N bond distances. The magnetic properties show that the complex undergoes a gradual change from low-spin iron(II) below 85 K to high-spin iron(II) at 400 K. The 4.2 to 60 K Mössbauer spectra correspond to a fully low-spin iron(II) complex but, upon further warming above 85 K, the iron(II) begins to undergo spin-state relaxation between the low- and high-spin forms on the Mössbauer time scale. At 155 and 315 K the complex exhibits spin-state relaxation rates of 0.36 and 7.38 MHz, respectively, and an Arrhenius plot of the logarithm of the relaxation rate yields an activation energy of 670 +/- 40 cm(-1) for the spin-state relaxation.


Asunto(s)
Electroquímica , Electrones , Proteínas Hierro-Azufre/química , Hierro/química , Magnetismo , Compuestos Férricos/química , Estructura Molecular , Difracción de Rayos X
12.
Inorg Chem ; 48(3): 936-45, 2009 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-19119870

RESUMEN

The third-generation bis(1-pyrazolyl)methane ligands p-C(6)H(4)[CH(2)OCH(2)CH(pz)(2)](2) (L(p), pz = pyrazolyl ring) and m-C(6)H(4)[CH(2)OCH(2)CH(pz)(2)](2) (L(m)) have been synthesized by the reaction of (pz)(2)CHCH(2)OH with NaH followed by alpha,alpha'-dibromo-p-xylene or alpha,alpha'-dibromo-m-xylene. The reaction of L(p) with AgBF(4), AgPF(6), and AgO(3)SCF(3) yields the new compounds {Ag[p-C(6)H(4)(CH(2)OCH(2)CH(pz)(2))(2)]}BF(4), {Ag[p-C(6)H(4)(CH(2)OCH(2)CH(pz)(2))(2)]}PF(6), and {Ag[p-C(6)H(4)(CH(2)OCH(2)CH(pz)(2))(2)]}O(3)SCF(3), respectively. A similar reaction of L(m) with AgBF(4) and AgPF(6) yields {Ag[m-C(6)H(4)(CH(2)OCH(2)CH(pz)(2))(2)]}BF(4) and {Ag[m-C(6)H(4)(CH(2)OCH(2)CH(pz)(2))(2)]}PF(6). These compounds were crystallized from both acetone and acetonitrile to yield nine crystalline forms of (LAg)(+) that differ in counterion and solvent of crystallization. In all complexes, the four pyrazolyl rings of the ligand chelate a single silver(I) cation in a distorted tetrahedral environment to form mononuclear metallacycles. This arrangement has not previously been observed with the analogous ligands based on tris(1-pyrazolyl)methane units and is unique because of the ring sizes (16-member rings in L(m) and 17-member rings in L(p)). The dominant feature in all of these solid state structures, regardless of solvent or anion, is this cationic metallacyclic architecture, which does not readily lend itself to strong supramolecular organization.

13.
Inorg Chem ; 46(26): 11345-55, 2007 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-17999497

RESUMEN

The new bitopic, bis(1-pyrazolyl)methane-based ligand o-C6H4[CH2OCH2CH(pz)2]2 (L2, pz = pyrazolyl ring) is prepared from the reaction of (pz)2CHCH2OH (obtained from the reduction of (pz)2CHCOOH with BH3.S(CH3)2) with NaH, followed by the addition of alpha,alpha'-dibromo-o-xylene. The reaction of L2 with AgPF6 or AgO3SCF3 yields {o-C6H4[CH2OCH2CH(pz)2]2(AgPF6)}n or {o-C6H4[CH2OCH2CH(pz)2]2(AgO3SCF3)}n, respectively. Both compounds in the solid state have tetrahedral silver(I) centers arranged in a 1D coordination polymer network. The analogous ligand based on tris(1-pyrazolyl)methane units, o-C6H4[CH2OCH2C(pz)3]2 (L3), reacts with AgO3SCF3 to form a similar coordination polymer, {o-C6H4[CH2OCH2C(pz)3]2(AgO3SCF3)}n. In this case, each tris(pyrazolyl)methane unit in L3 adopts the kappa2-kappa0 bonding mode. Crystallization of a 3:1 mixture of AgO3SCF3 and L3 yields {o-C6H4[CH2OCH2C(pz)3]2(AgO3SCF3)2}n, in which the tris(1-pyrazolyl)methane units adopt a kappa2-kappa1 coordination mode.

14.
Integr Physiol Behav Sci ; 38(3): 189-202, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-15070082

RESUMEN

This paper reviews recent findings from our laboratories concerning metabolic and immune mediators of behavioral depression in rats. Specifically, a single injection of 6 mg/kg of reserpine substantially increases behavioral depression, as evidenced by an increase in the amount of time spent floating by independent groups of rats tested for swim performance at various times during the next week. The behavioral impairment consists of two components. An early component emerges one hour after reserpine treatment and persists for about 24 hours. The deficit is not reversed by intracranial ventricular infusion of the receptor antagonist for interleukin-1beta (IL-1beta). A second, late-component deficit appears approximately 48 hours after reserpine treatment and recovers within a week. Late-component depression is reversed by central infusion of the IL-1beta receptor antagonist, and is mimicked by central infusion of the proinflammatory cytokine. Importantly, both early and late components of reserpine-induced depression and IL-1beta induced depression are reversed by a systemic injection of the highly selective A2A adenosine receptor antagonist 8-(3-Chlorostyryl) caffeine. These data are discussed in terms of the overlap in the conservation-withdrawal reaction during sickness, traumatic stress, and major depression and the regional contribution of purines and cytokines to the organization of this reaction in the brain.


Asunto(s)
Cafeína/análogos & derivados , Desamparo Adquirido , Interleucina-1/farmacología , Motivación , Actividad Motora/efectos de los fármacos , Reserpina/farmacología , Antagonistas del Receptor de Adenosina A1 , Animales , Nivel de Alerta/efectos de los fármacos , Encéfalo/efectos de los fármacos , Cafeína/farmacología , Interacciones Farmacológicas , Inyecciones Intraventriculares , Ratas , Receptores de Interleucina-1/antagonistas & inhibidores
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