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1.
J Acoust Soc Am ; 155(5): 3090-3100, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38717212

RESUMEN

The perceived level of femininity and masculinity is a prominent property by which a speaker's voice is indexed, and a vocal expression incongruent with the speaker's gender identity can greatly contribute to gender dysphoria. Our understanding of the acoustic cues to the levels of masculinity and femininity perceived by listeners in voices is not well developed, and an increased understanding of them would benefit communication of therapy goals and evaluation in gender-affirming voice training. We developed a voice bank with 132 voices with a range of levels of femininity and masculinity expressed in the voice, as rated by 121 listeners in independent, individually randomized perceptual evaluations. Acoustic models were developed from measures identified as markers of femininity or masculinity in the literature using penalized regression and tenfold cross-validation procedures. The 223 most important acoustic cues explained 89% and 87% of the variance in the perceived level of femininity and masculinity in the evaluation set, respectively. The median fo was confirmed to provide the primary cue, but other acoustic properties must be considered in accurate models of femininity and masculinity perception. The developed models are proposed to afford communication and evaluation of gender-affirming voice training goals and improve voice synthesis efforts.


Asunto(s)
Señales (Psicología) , Acústica del Lenguaje , Percepción del Habla , Calidad de la Voz , Humanos , Femenino , Masculino , Adulto , Adulto Joven , Masculinidad , Persona de Mediana Edad , Feminidad , Adolescente , Identidad de Género , Acústica
2.
J Speech Lang Hear Res ; 66(7): 2246-2259, 2023 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-37263019

RESUMEN

PURPOSE: To date, transgender and gender-diverse voice clients' perceptions and individual goals have been missing in discussions and research on gender-affirming voice therapy. Little is, therefore, known about the client's expectations of therapy outcomes and how these are met by treatments developed from views of vocal gender as perceived by cisgender persons. This study aimed to explore clients' individual motives and perceived barriers to undertaking gender-affirming voice therapy. METHOD: Individual, semistructured interviews with 15 transgender and gender-diverse voice clients considering voice therapy were conducted and explored using qualitative content analysis. RESULTS: Three themes were identified during the analysis of the participants' narratives. In the first theme, "the incongruent voice setting the rules," the contribution of the voice on the experienced gender dysphoria is put in focus. The second theme, "to reach a voice of my own choice," centers around anticipated personal gains using a modified voice. The third theme, "a voice out of reach," relates to worries and restricting factors for not being able to reach one's set goals for voice modification. CONCLUSIONS: The interviews clearly indicate a need for a person-centered voice therapy that starts from the individuals' expressed motives for modifying the voice yet also are affirmative of anticipated difficulties related to voice modification. We recommend that these themes should form the basis of the pretherapy joint discussion between the voice client and the speech-language pathologist to ensure therapy goals that are realistic and relevant to the client.


Asunto(s)
Personas Transgénero , Transexualidad , Voz , Humanos , Motivación , Identidad de Género
3.
Drug Test Anal ; 9(5): 734-743, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27400773

RESUMEN

Herbal smoking blends containing synthetic cannabinoids have become popular alternatives to marijuana. These products were previously sold in pre-packaged foil bags, but nowadays seizures usually contain synthetic cannabinoid powders together with unprepared plant materials. A question often raised by the Swedish police is how much smoking blend can be prepared from certain amounts of banned substance, in order to establish the severity of the crime. To address this question, information about the synthetic cannabinoid content in both the powder and the prepared herbal blends is necessary. In this work, an extraction procedure compatible with direct NMR quantification of synthetic cannabinoids in herbal smoking blends was developed. Extraction media, time and efficiency were tested for different carrier materials containing representative synthetic cannabinoids. The developed protocol utilizes a 30 min extraction step in d4 -methanol in presence of internal standard allowing direct quantitation of the extract using NMR. The accuracy of the developed method was tested using in-house prepared herbal smoking blends. The results showed deviations less than 0.2% from the actual content, proving that the method is sufficiently accurate for these quantifications. Using this method, ten synthetic cannabinoids present in sixty-three different herbal blends seized by the Swedish police between October 2012 and April 2015 were quantified. Obtained results showed a variation in cannabinoid contents from 1.5% (w/w) for mixtures containing MDMB-CHMICA to over 5% (w/w) for mixtures containing 5F-AKB-48. This is important information for forensic experts when making theoretical calculations of production quantities in legal cases regarding "home-made" herbal smoking blends. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Adamantano/análogos & derivados , Cannabinoides/análisis , Drogas Ilícitas/análisis , Indazoles/análisis , Indoles/análisis , Espectroscopía de Resonancia Magnética/métodos , Preparaciones de Plantas/análisis , Adamantano/análisis , Humanos , Metanol/química , Fumar Productos sin Tabaco/epidemiología , Solventes/química , Suecia/epidemiología
4.
Biomater Sci ; 3(8): 1208-17, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26222036

RESUMEN

Heparin-imprinted synthetic polymer surfaces with the ability to attenuate activation of both the complement and the coagulation system in whole blood were successfully produced. Imprinting was achieved using a template coated with heparin, a highly sulfated glycosaminoglycan known for its anticoagulant properties. The N,N'-diacryloylpiperazine-methacrylic acid copolymers were characterized using goniometry, AFM and XPS. The influence of the molecular imprinting process on morphology and template rebinding was demonstrated by radioligand binding assays. Surface hemocompatibility was evaluated using human whole blood without anticoagulants followed by measurement of complement activation markers C3a and sC5b-9 and platelet consumption as a surrogate coagulation activation marker. The observed low thrombogenicity of this copolymer combined with the attenuation of complement activation induced by the molecular imprint offer potential for the development of self-regulating surfaces with important potential clinical applications. We propose a mechanism for the observed phenomena based upon the recruitment of endogenous sulfated glycosaminoglycans with heparin-like activities.


Asunto(s)
Anticoagulantes/química , Complejo de Ataque a Membrana del Sistema Complemento/química , Glicosaminoglicanos/química , Heparina/química , Metacrilatos/química , Piperazinas/química , Polímeros/química , Anticoagulantes/metabolismo , Coagulación Sanguínea , Activación de Complemento , Complejo de Ataque a Membrana del Sistema Complemento/metabolismo , Glicosaminoglicanos/metabolismo , Humanos , Recuento de Plaquetas , Propiedades de Superficie
5.
Biomaterials ; 36: 55-65, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25292422

RESUMEN

Inappropriate complement activation is often responsible for incompatibility reactions that occur when biomaterials are used. Complement activation is therefore a criterion included in legislation regarding biomaterials testing. However, no consensus is yet available regarding appropriate complement-activation-related test parameters. We examined protein adsorption in plasma and complement activation/cytokine release in whole blood incubated with well-characterized polymers. Strong correlations were found between the ratio of C4 to its inhibitor C4BP and generation of 10 (mainly pro-inflammatory) cytokines, including IL-17, IFN-γ, and IL-6. The levels of complement activation products correlated weakly (C3a) or not at all (C5a, sC5b-9), confirming their poor predictive values. We have demonstrated a direct correlation between downstream biological effects and the proteins initially adhering to an artificial surface after contact with blood. Consequently, we propose the C4/C4BP ratio as a robust, predictor of biocompatibility with superior specificity and sensitivity over the current gold standard.


Asunto(s)
Materiales Biocompatibles/efectos adversos , Activación de Complemento/efectos de los fármacos , Inflamación/sangre , Inflamación/inducido químicamente , Polímeros/efectos adversos , Proteína de Unión al Complemento C4b/inmunología , Complejo de Ataque a Membrana del Sistema Complemento/inmunología , Proteínas del Sistema Complemento/inmunología , Humanos , Inflamación/inmunología , Interferón gamma/inmunología , Interleucina-17/sangre , Interleucina-17/inmunología , Interleucina-6/sangre , Interleucina-6/inmunología
6.
Sci Technol Adv Mater ; 15(3): 035009, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27877685

RESUMEN

There can be a large variation in the measured diameter of nanoparticles depending on which method is used. In this work, we have strived to accurately determine the mean particle diameter of 30-40 nm colloidal silica particles by using six different techniques. A quantitative agreement between the particle size distributions was obtained by scanning electron microscopy (SEM), and electrospray-scanning mobility particle sizer (ES-SMPS). However, transmission electron microscopy gave a distribution shifted to smaller sizes. After confirming that the magnification calibration was consistent, this was attributed to sample preparation artifacts. The hydrodynamic diameter, dh , was determined by dynamic light scattering (DLS) both in batch mode, and hyphenated with sedimentation field flow fractionation. Surprisingly the dh were smaller than the SEM, and ES-SMPS diameters. A plausible explanation for the smaller sizes found with DLS is that a permeable gel layer forms on the particle surface. Results from nanoparticle tracking analysis were strongly biased towards larger diameters, most likely because the silica particles provide low refractive index contrast. Calculations confirmed that the sensitivity is, depending on the shape of the laser beam, strongly size dependent for particles with diameters close to the visualization limit.

7.
J Colloid Interface Sci ; 407: 168-76, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-23859811

RESUMEN

Size dependent surface charging and interfacial potential of titanium dioxide (TiO2) nanoparticles are investigated by experimental and theoretical methods. Commercially available TiO2 (P25) nanoparticles were used for surface charge determinations by potentiometric titrations. Anatase particles, 10 and 22 nm in diameter, were synthesized by controlled hydrolysis of TiCl4, and electrophoretic mobilities were determined at a fixed pH but at increasing salt concentrations. Corrected Debye-Hückel theory of surface complexation (CDH-SC) was modified to model the size dependent surface charging behavior of TiO2 nanoparticles. Experimentally determined surface charge densities of rutile and P25 nanoparticles in different electrolytes were accurately modeled by the CDH-SC theory. Stern layer capacitances calculated by the CDH-SC theory were in good agreement with the values found by the classical surface complexation approach, and the interaction of protons with OH groups is found to be less exothermic than for iron oxide surfaces. Moreover, the CDH-SC theory predicts that the surface charge density of TiO2 nanoparticles of diameter <10nm is considerably higher than for larger particles, and pH at the point of zero charge (pHPZC) shifts to higher pH values as the particle size decreases. The importance of including the particle size in calculating the zeta potentials from mobilities is demonstrated. Smoluchowski theory showed that 10nm particles had lower zeta potential than 22 nm particles, whereas a reverse trend was seen when zeta potentials were calculated by Ohshima's theory in which particle size is included. Electrokinetic charge densities calculated from zeta potentials were found to be only one third of the true surface charge densities.


Asunto(s)
Nanopartículas del Metal/química , Modelos Teóricos , Titanio/química , Coloides/química , Concentración de Iones de Hidrógeno , Potenciometría , Propiedades de Superficie
8.
Int J Dent ; 2013: 139615, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23737786

RESUMEN

Nanoparticle-covered electrodes have altered properties as compared to conventional electrodes with same chemical composition. The changes originate from the large surface area and enhanced conduction. To test the mineralization capacity of such materials, TiO2 nanoparticles were deposited on titanium and gold substrates. The electrochemical properties were investigated using cyclic voltammetry and impedance spectroscopy while the mineralization was tested by immersion in simulated body fluid. Two types of nucleation and growth behaviours were observed. For smooth nanoparticle surfaces, the initial nucleation is fast with the formation of few small nuclei of hydroxyapatite. With time, an amorphous 2D film develops with a Ca/P ratio close to 1.5. For the rougher surfaces, the nucleation is delayed but once it starts, thick layers are formed. Also the electronic properties of the oxides were shown to be important. Both density of states (DOS) in the bandgap of TiO2 and the active area were determined. The maximum in DOS was found to correlate with the donor density (N d ) and the active surface area. The results clearly show that a rough surface with high conductivity is beneficial for formation of thick apatite layers, while the nanoparticle covered electrodes show early nucleation but limited apatite formation.

9.
J Biomed Mater Res A ; 97(1): 74-84, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21319295

RESUMEN

The aim of this study was to create polymeric materials with known properties to study the preconditions for complement activation. Initially, 22 polymers were screened for complement activating capacity. Based on these results, six polymers (P1-P6) were characterized regarding physico-chemical parameters, for example, composition, surface area, pore size, and protein adsorption from human EDTA-plasma. P2, P4, and reference particles of polystyrene and polyvinyl chloride, were hydrophobic, bound low levels of protein and were poor complement activators. Their accessible surface was limited to protein adsorption in that they had pore diameters smaller than most plasma proteins. P1 and P3 were negatively charged and adsorbed IgG and C1q. A 10-fold difference in complement activation was attributed to the fact that P3 but not P1 bound high amounts of C1-inhibitor. The hydrophobic P5 and P6 were low complement activators. They selectively bound apolipoproteins AI and AIV (and vitronectin), which probably limited the binding of complement activators to the surface. We demonstrate the usefulness of the modus operandi to use a high-throughput procedure to synthesize a great number of novel substances, assay their physico-chemical properties with the aim to study the relationship between the initial protein coat on a surface and subsequent biological events. Data obtained from the six polymers characterized here, suggest that a complement-resistant surface should be hydrophobic, uncharged, and have a small available surface, accomplished by nanostructured topography. Additional attenuation of complement can be achieved by selective enrichment of inert proteins and inhibitors.


Asunto(s)
Proteínas Sanguíneas/química , Proteínas del Sistema Complemento/metabolismo , Ensayo de Materiales/métodos , Polímeros/química , Adsorción , Western Blotting , Activación de Complemento , Reactivos de Enlaces Cruzados/química , Electroforesis en Gel de Poliacrilamida , Endotoxinas/metabolismo , Citometría de Flujo , Hirudinas/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Rastreo , Porosidad
10.
Langmuir ; 22(17): 7302-12, 2006 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-16893230

RESUMEN

We have previously described the efficient guidance and unidirectional sliding of actin filaments along nanosized tracks with adsorbed heavy meromyosin (HMM; myosin II motor fragment). In those experiments, the tracks were functionalized with trimethylchlorosilane (TMCS) by chemical vapor deposition (CVD) and surrounded by hydrophilic areas. Here we first show, using in vitro motility assays on nonpatterned and micropatterned surfaces, that the quality of HMM function on CVD-TMCS is equivalent to that on standard nitrocellulose substrates. We further examine the influences of physical properties of different surfaces (glass, SiO(2), and TMCS) and chemical properties of the buffer solution on motility. With the presence of methylcellulose in the assay solution, there was HMM-induced actin filament sliding on both glass/SiO(2) and on TMCS, but the velocity was higher on TMCS. This difference in velocity increased with decreasing contact angles of the glass and SiO(2) surfaces in the range of 20-67 degrees (advancing contact angles for water droplets). The corresponding contact angle of CVD-TMCS was 81 degrees. In the absence of methylcellulose, there was high-quality motility on TMCS but no motility on glass/SiO(2). This observation was independent of the contact angle of the glass/SiO(2) surfaces and of HMM incubation concentrations (30-150 microg mL(-)(1)) and ionic strengths of the assay solution (20-50 mM). Complete motility selectivity between TMCS and SiO(2) was observed for both nonpatterned and for micro- and nanopatterned surfaces. Spectrophotometric analysis of HMM depletion during incubation, K/EDTA ATPase measurements, and total internal reflection fluorescence spectroscopy of HMM binding showed only minor differences in HMM surface densities between TMCS and SiO(2)/glass. Thus, the motility contrast between the two surface chemistries seems to be attributable to different modes of HMM binding with the hindrance of actin binding on SiO(2)/glass.


Asunto(s)
Actomiosina/fisiología , Proteínas Motoras Moleculares/fisiología , Dióxido de Silicio/química , Compuestos de Trimetilsililo/química , Colodión/química , Nanotecnología/métodos , Propiedades de Superficie
11.
J Org Chem ; 71(13): 4845-53, 2006 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-16776512

RESUMEN

[structures: see text] A class II aldolase-mimicking synthetic polymer was prepared by the molecular imprinting of a complex of cobalt (II) ion and either (1S,3S,4S)-3-benzoyl-1,7,7-trimethylbicyclo[2.2.1]heptan-2-one (4a) or (1R,3R,4R)-3-benzoyl-1,7,7-trimethylbicyclo[2.2.1]heptan-2-one (4b) in a 4-vinylpyridine-styrene-divinylbenzene copolymer. Evidence for the formation of interactions between the functional monomer and the template was obtained from NMR and VIS titration studies. The polymers imprinted with the template demonstrated enantioselective recognition of the corresponding template structure, and induced a 55-fold enhancement of the rate of reaction of camphor (1) with benzaldehyde (2), relative to the solution reactions, and were also compared to reactions with a series of reference polymers. Substrate chirality was observed to influence reaction rate, and the reaction could be competitively inhibited by dibenzoylmethane (6). Collectively, the results presented provide the first example of the use of enantioselective molecularly imprinted polymers for the catalysis of carbon-carbon bond formation.


Asunto(s)
Aldehído-Liasas/química , Aldehído-Liasas/clasificación , Benzaldehídos/química , Alcanfor/química , Cetonas/síntesis química , Polímeros/química , Aldehído-Liasas/antagonistas & inhibidores , Catálisis , Chalconas/química , Chalconas/farmacología , Cobalto/química , Cetonas/química , Cinética , Ligandos , Estructura Molecular , Compuestos Organometálicos/química , Polímeros/síntesis química , Estereoisomerismo , Factores de Tiempo
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