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1.
Chemistry ; 30(7): e202302750, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37996997

RESUMO

Slightly different reaction conditions afforded two distinct cavity-shaped cis-chelating diphosphanes from the same starting materials, namely diphenyl(2-phosphanylphenyl)phosphane and an α-cyclodextrin-derived dimesylate. Thanks to their metal-confining properties, the two diphosphanes form only mononuclear [CuX(PP)] complexes (X=Cl, Br, or I) with the tricoordinated metal ion located just above the center of the cavity. The two series of CuI complexes display markedly different luminescence properties that are both influenced by the electronic properties of the ligand and the unique steric environment provided by the cyclodextrin (CD) cavity. The excited state lifetimes of all complexes are significantly longer than those of the cavity-free analogues suggesting peculiar electronic effects that affect radiative deactivation constants. The overall picture stemming from absorption and emission data suggests close-lying charge-transfer (MLCT, XLCT) and triplet ligand-centered (LC) excited states.

2.
Molecules ; 28(11)2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37298847

RESUMO

This paper reports the synthesis, structure, photophysical, and optoelectronic properties of five eight-coordinate Europium(III) ternary complexes, namely, [Eu(hth)3(L)2], bearing 4,4,5,5,6,6,6-heptafluoro-1-(2-thienyl)-1,3-hexanedione (hth) as a sensitizer and L = H2O (1), dpso (diphenyl sulphoxide, 2), dpsoCH3 (4,4'-dimethyl diphenyl sulfoxide, 3), dpsoCl (bis(4-chlorophenyl)sulphoxide, 4), and tppo (triphenylphosphine oxide, 5) as co-ligands. The NMR and the crystal structure analysis confirmed the eight-coordinate structures of the complexes in solution and in a solid state. Upon UV-excitation on the absorption band of the ß-diketonate ligand hth, all complexes showed the characteristic bright red luminescence of the Europium ion. The tppo derivative (5) displayed the highest quantum yield (up to 66%). As a result, an organic light-emitting device, OLED, was fabricated with a multi-layered structure-ITO/MoO3/mCP/SF3PO:[complex 5] (10%)/TPBi:[complex 5] (10%)/TmPyPB/LiF/Al-using complex 5 as the emitting component.


Assuntos
Európio , Polimetil Metacrilato , Európio/química , Polimetil Metacrilato/química , Luminescência , Cetonas/química , Ligantes
3.
Angew Chem Int Ed Engl ; 62(6): e202214638, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36433744

RESUMO

A ß-cyclodextrin-based diphosphane with metal-confining properties was efficiently synthesized thanks to an unprecedented Smiles-like rearrangement of diphenyl-(2-phosphanylphenyl)phosphane in the presence of excess n-BuLi. The cis-chelating bidentate ligand is capable of forming very stable heteroleptic [Cu(NN)(PP)]+ complexes in which a metal-bound diimine ligand (bpy, phen, or mmp) is located within the cyclodextrin cavity. As a result of ligand encapsulation, flattening of the metal tetrahedral geometry in the excited state is disfavored, thereby resulting in enhanced luminescent properties.

4.
Molecules ; 27(18)2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36144738

RESUMO

Heteroleptic cyclometalated iridium (III) complexes (1-3) containing di-pyridylamine motifs were prepared in a stepwise fashion. The presence of the di-pyridylamine ligands tunes their electronic and optical properties, generating blue phosphorescent emitters at room temperature. Herein we describe the synthesis of the mononuclear iridium complexes [Ir(ppy)2(DPA)][OTf] (1), (ppy = phenylpyridine; DPA = Dipyridylamine) and [Ir(ppy)2(DPA-PhI)][OTf] (2), (DPA-PhI = Dipyridylamino-phenyliodide). Moreover, the dinuclear iridium complex [Ir(ppy)2(L)Ir(ppy)2][OTf]2 (3) containing a rigid angular ligand "L = 3,5-bis[4-(2,2'-dipyridylamino)phenylacetylenyl]toluene" and displaying two di-pyridylamino groups was also prepared. For comparison purposes, the related dinuclear rhodium complex [Rh (ppy)2(L)Rh(ppy)2][OTf]2 (4) was also synthesized. The x-ray molecular structure of complex 2 was reported and confirmed the formation of the target molecule. The rhodium complex 4 was found to be emissive only at low temperature; in contrast, all iridium complexes 1-3 were found to be phosphorescent in solution at 77 K and room temperature, displaying blue emissions in the range of 478-481 nm.

5.
Am J Primatol ; 83(1): e23224, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33337547

RESUMO

Studies on primate tool-use often involve the use of baseline conditions, as they allow for the examination of any differences in the subjects' behavior before and after the introduction of a tool-use task. While these baseline conditions can be powerful for identifying the relative contributions of individual and social learning for the acquisition of tool-use behaviors in naïve (usually captive) subjects, many have criticized them for being too short, and not allowing enough time for the behavior to develop spontaneously. Furthermore, some wild tool-use behaviors such as chimpanzee nut-cracking require animals to manipulate and familiarize themselves with the materials of the behavior within a "sensitive learning period" before it develops later on in life. One solution to this problem is to implement long-term baselines, in which, with collaboration with zoological institutions, the materials of the behavior are left in the enclosure for an extended period. The keepers would then be asked not to demonstrate or train the animals in the target behavior, but to report back to the researchers if they observe the behavior emerge during this extended period. Alongside keeper reports, video cameras could be installed in the enclosure to minimize the chance of false negatives and to allow for coding and inter-rater reliability to be carried out on the videos. These long-term baselines therefore provide extended enrichment opportunities for the animals, alongside allowing the zoological institution to publicize their involvement with the study and guests to observe animals interacting with different testing apparatuses and tools. Finally, long-term baselines can provide invaluable insight on the individual and social learning abilities of primates as well as the potential development stages and sensitive learning periods required for specific behaviors.


Assuntos
Primatas/psicologia , Comportamento de Utilização de Ferramentas , Zoologia/métodos , Animais , Animais Selvagens , Animais de Zoológico
6.
Am J Primatol ; 83(9): e23304, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34378813

RESUMO

Nut-cracking with hammer tools (henceforth: nut-cracking) has been argued to be one of the most complex tool-use behaviors observed in nonhuman animals. So far, only chimpanzees, capuchins, and macaques have been observed using tools to crack nuts in the wild (Boesch and Boesch, 1990; Gumert et al., 2009; Mannu and Ottoni, 2009). However, the learning mechanisms behind this behavior, and the extent of nut-cracking in other primate species are still unknown. The aim of this study was two-fold. First, we investigated whether another great ape species would develop nut-cracking when provided with all the tools and appropriate conditions to do so. Second, we examined the mechanisms behind the emergence of nut-cracking by testing a naïve sample. Orangutans (Pongo abelii and Pongo pygmaeus) have the second most extensive tool-use repertoire among the great apes (after chimpanzees) and show flexible problem-solving capacities. Orangutans have not been observed cracking nuts in the wild, however, perhaps because their arboreal habits provide limited opportunities for nut-cracking. Therefore, orangutans are a valid candidate species for the investigation of the development of this behavior. Four nut-cracking-naïve orangutans at Leipzig zoo (P. abelii; Mage = 16; age range = 10-19; 4F; at the time of testing) were provided with nuts and hammers but were not demonstrated the nut-cracking behavioral form. Additionally, we report data from a previously unpublished study by one of the authors (Martina Funk) with eight orangutans housed at Zürich zoo (six P. abelii and two P. pygmaeus; Mage = 14; age range = 2-30; 5F; at the time of testing) that followed a similar testing paradigm. Out of the twelve orangutans tested, at least four individuals, one from Leipzig (P. abelii) and three from Zürich (P. abelii and P. pygmaeus), spontaneously expressed nut-cracking using wooden hammers. These results demonstrate that nut-cracking can emerge in orangutans through individual learning and certain types of non-copying social learning.


Assuntos
Pongo abelii , Comportamento de Utilização de Ferramentas , Animais , Nozes , Pongo pygmaeus , Resolução de Problemas
7.
Chemistry ; 26(48): 11013-11023, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32301186

RESUMO

Five extended π-conjugated systems with electron donor (D) and acceptor (A) moieties have been synthesized. Their basic D-A-D structural motif is a benzothiadiazole unit symmetrically equipped with two thiophene rings (S2T). Its variants include 1) the same molecular framework in which sulfur is replaced by selenium (Se2T), also with four thiophene units (Se4T) and 2) a D'-D-A-D system having a N-carbazole donor moiety at one end (CS2T) and a D'-D-A-D-A' array with a further acceptor carbonyl unit at the other extremity (CS2TCHO). The goal is taking advantage of the intense luminescence and large Stokes shifts of the five molecules for use in luminescent solar concentrators (LSCs). All of them exhibit intense absorption spectra in the UV/Vis region down to 630 nm, which are fully rationalized by DFT. Emission properties have been studied in CH2 Cl2 (298 and 77 K) as well as in PMMA and PDMS matrices, measuring photoluminescence quantum yields (up to 98 %) and other key optical parameters. The dye-PMMA systems show performances comparable to the present state-of-the-art, in terms of optical and external quantum efficiencies (OQE=47.6 % and EQE=31.3 %, respectively) and flux gain (F=10.3), with geometric gain close to 90. LSC devices have been fabricated and tested in which the five emitters are embedded in PDMS and their wave-guided VIS luminescence feeds crystalline silicon solar cells.

8.
Biol Lett ; 16(6): 20200122, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32486940

RESUMO

Despite major advances in the study of animal tool behaviour, researchers continue to debate how exactly certain behaviours are acquired. While specific mechanisms, such as genetic predispositions or action copying, are sometimes suspected to play a major role in behavioural acquisition, controlled experiments are required to provide conclusive evidence. In this opinion piece, we refer to classic ethological methodologies to emphasize the need for studying the relative contributions of different factors to the emergence of specific tool behaviours. We describe a methodology, consisting of a carefully staged series of baseline and social-learning conditions, that enables us to tease apart the roles of different mechanisms in the development of behavioural repertoires. Experiments employing our proposed methodology will not only advance our understanding of animal learning and culture, but as a result, will also help inform hypotheses about human cognitive, cultural and technological evolution. More generally, our conceptual framework is suitable for guiding the detailed investigation of other seemingly complex animal behaviours.


Assuntos
Comportamento Animal , Aprendizagem , Animais , Humanos
9.
Behav Brain Sci ; 43: e173, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32772970

RESUMO

To support their claim for technical reasoning skills rather than imitation as the key for cumulative technological culture (CTC), Osiurak and Reynaud argue that chimpanzees can imitate mechanical actions, but do not have CTC. They also state that an increase in working memory in human evolution could not have been a key driver of CTC. We discuss why we disagree with these claims.


Assuntos
Comportamento Imitativo , Memória de Curto Prazo , Humanos , Resolução de Problemas , Tecnologia
10.
Am J Primatol ; 81(6): e22987, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31087361

RESUMO

Many studies investigating culture in nonhuman animals tend to focus on the inferred need of social learning mechanisms that transmit the form of a behavior to explain the population differences observed in wild animal behavioral repertoires. This research focus often results in studies overlooking the possibility of individuals being able to develop behavioral forms without requiring social learning. The disregard of individual learning abilities is most clearly observed in the nonhuman great ape literature, where there is a persistent claim that chimpanzee behaviors, in particular, require various forms of social learning mechanisms. These special social learning abilities have been argued to explain the acquisition of the relatively large behavioral repertoires observed across chimpanzee populations. However, current evidence suggests that although low-fidelity social learning plays a role in harmonizing and stabilizing the frequency of behaviors within chimpanzee populations, some (if not all) of the forms that chimpanzee behaviors take may develop independently of social learning. If so, they would be latent solutions-behavioral forms that can (re-)emerge even in the absence of observational opportunities, via individual (re)innovations. Through a combination of individual and low-fidelity social learning, the population-wide patterns of behaviors observed in great ape species are then established and stably maintained. This is the Zone of Latent Solutions (ZLS) hypothesis. The current study experimentally tested the ZLS hypothesis for pestle pounding, a wild chimpanzee behavior. We tested the reinnovation of this behavior in semi-wild chimpanzees at Chimfunshi Wildlife Orphanage in Zambia, Africa, (N = 90, tested in four social groups). Crucially, all subjects were naïve to stick pounding before testing. Three out of the four tested groups reinnovated stick pounding-clearly demonstrating that this behavioral form does not require social learning. These findings provide support for the ZLS hypothesis alongside further evidence for the individual learning abilities of chimpanzees.


Assuntos
Pan troglodytes/psicologia , Comportamento de Utilização de Ferramentas , Animais , Aprendizagem , Comportamento Social , Gravação em Vídeo
11.
J Am Chem Soc ; 140(6): 2336-2347, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-29298047

RESUMO

A series of copper(I) pseudorotaxanes has been prepared from bis[2-(diphenylphosphino)phenyl] ether (POP) and macrocyclic phenanthroline ligands with different ring sizes (m30, m37, and m42). Variable-temperature studies carried out on the resulting [Cu(mXX)(POP)]+ (mXX = m30, m37, and m42) derivatives have revealed a dynamic conformational equilibrium due to the folding of the macrocyclic ligand. The absorption and luminescence properties of the pseudorotaxanes have been investigated in CH2Cl2. They exhibit metal-to-ligand charge-transfer emission with photoluminescence quantum yields (PLQYs) in the range 20-30%. The smallest system [Cu(m30)(POP)]+ shows minimal differences in spectral shape and position compared to its analogues, suggesting a slightly distorted coordination environment. PLQY is substantially enhanced in poly(methyl methacrylate) films (∼40-45%). The study of emission spectra and excited-state lifetimes in powder samples as a function of temperature (78-338 K) reveals thermally activated delayed fluorescence, with sizable differences in the singlet-triplet energy gap compared to the reference compound [Cu(dmp)(POP)]+ (dmp = 2,9-dimethyl-1,10-phenanthroline) and within the pseudorotaxane series. The system with the largest ring ([Cu(m42)(POP)]+) has been tested as emissive material in OLEDs and affords bright green devices with higher luminance and greater stability compared to [Cu(dmp)(POP)]+, which lacks the macrocyclic ring. This highlights the importance of structural factors in the stability of electroluminescent devices based on Cu(I) materials.

12.
Inorg Chem ; 56(4): 2050-2059, 2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-28182410

RESUMO

A series of cyclometalated platinum(II) complexes of the type [(ppy)Pt(LM)]n+ (n = 0, 1) with π-bonded catecholates acting as organometallic ligands (LM) have been prepared and characterized by analytical techniques. In addition, the structures of two complexes of the series were determined by single-crystal X-ray diffraction. The packing shows the formation of a 1D supramolecular assembly generated by dPt-πCp* interactions among individual units. All complexes are luminescent in the solid state and in solution media. The results of photophysics have been rationalized by means of density functional theory (DFT) and time-dependent DFT investigations.

13.
J Sex Med ; 12(12): 2413-24, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26612786

RESUMO

INTRODUCTION: An increased risk of autistic traits in Klinefelter syndrome (KS) has been reported. In addition, some studies have shown an increased incidence of gender dysphoria (GD) and paraphilia in autism spectrum disorder. AIM: The aim of this study was to evaluate the presence of (i) paraphilic fantasies and behaviors; and (ii) GD symptomatology in KS. METHODS AND MAIN OUTCOMES MEASURES: A sample of 46 KS individuals and 43 healthy male controls (HC) were evaluated. Subjects were studied by means of several psychometric tests, such as Autism Spectrum Quotient (AQ) and Reading the Mind in the Eyes Revised (RME) to measure autistic traits, Gender Identity/GD questionnaire (GIDYQ-AA), and Sexual Addiction Screening Test (SAST). In addition, body uneasiness psychopathological symptoms were assessed using Symptom Checklist 90 Revised (SCL-90-R). The presence and frequency of any paraphilic fantasy and behavior was assessed by means of a clinical interview based on Diagnostic and Statistical Manual of Mental Disorders, 5th Edition criteria. Finally, all individuals included were assessed by Wechsler Adult Intelligence Scale-Revised to evaluate intelligence quotient (IQ). Data from a subsample of a previous published series of male to female GD individuals, with the battery of psychological measures useful to provide a psychopathological explanation of GD in KS population available, was also considered. RESULTS: When compared with HC, KS reported significantly lower total, verbal and performance IQ scores and higher SCL-90 obsession-compulsive symptoms (all P < 0.001). In line with previously reported findings, KS showed higher autistic traits according with both RME and AQ tests (P < 0.001). With respect to sexuality, KS showed a significant higher frequency of voyeuristic fantasies during masturbation (52.2% vs. 25.6%) and higher SAST scores (P = 0.012). A mediation role of obsessive symptoms on the relationship between Klinefelter and SAST was confirmed (unstandardized estimate b = 2.75, standard error = 0.43 P < 0.001). Finally, KS individuals showed significantly higher gender dysphoric symptoms than HC (P = 0.004), which were mediated by the presence of autistic traits (Sobel's test; P < 0.05). CONCLUSIONS: KS is associated with hypersexuality, paraphilic behaviors, and GD, which were mediated by obsessive-compulsive and autistic traits.


Assuntos
Transtorno Autístico/etiologia , Disforia de Gênero/etiologia , Síndrome de Klinefelter/psicologia , Transtornos Parafílicos/etiologia , Comportamento Sexual , Adolescente , Adulto , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Disforia de Gênero/diagnóstico , Disforia de Gênero/psicologia , Identidade de Gênero , Humanos , Síndrome de Klinefelter/complicações , Síndrome de Klinefelter/genética , Masculino , Transtornos Parafílicos/diagnóstico , Transtornos Parafílicos/psicologia , Fenótipo , Sexualidade , Inquéritos e Questionários
14.
Chem Soc Rev ; 43(12): 4222-42, 2014 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-24553456

RESUMO

Oligo(phenylenevinylene)s (OPVs) are extensively investigated π-conjugated molecules that exhibit absorption and fluorescence in the UV-Vis spectral region, which can be widely tuned by chemical functionalisation and external control (e.g. solvent, temperature, pH). Further modulation of the optoelectronic properties of OPVs is possible by supramolecular aggregation, primarily driven by hydrogen bonding or π-stacking interactions. In recent years, extensive research work has been accomplished in exploiting the unique combination of the structural and electronic properties of OPVs, most of which has been targeted at the preparation of molecules and materials featuring photoinduced energy transfer. This review intends to offer an overview of the multicomponent arrays and self-assembled materials based on OPV which have been designed to undergo energy transfer by means of a thorough choice of excitation donor-acceptor partners. We present a few selected examples of photoactive dyads and triads containing organic moieties (e.g. fullerene, phenanthroline) as well as coordination compounds (Cu(I) complexes). We then focus more extensively on self-assembled materials containing suitably functionalised OPVs that lead to hydrogen bonded aggregates, helical structures, gels, nanoparticles, vesicles, mesostructured organic-inorganic hybrid films, functionalised nanoparticles and quantum dots. In most cases, these materials exhibit luminescence whose colour and intensity is related to the efficiency and direction of the energy transfer processes.


Assuntos
Polivinil/química , Complexos de Coordenação/química , Transporte de Elétrons/efeitos da radiação , Transferência de Energia/efeitos da radiação , Fulerenos/química , Luz , Fenantrolinas/química , Pontos Quânticos/química
15.
J Sex Med ; 11(10): 2500-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25066178

RESUMO

INTRODUCTION: Differences in facial preferences between heterosexual men and women are well documented. It is still a matter of debate, however, how variations in sexual identity/sexual orientation may modify the facial preferences. AIM: This study aims to investigate the facial preferences of male-to-female (MtF) individuals with gender dysphoria (GD) and the influence of short-term/long-term relationships on facial preference, in comparison with healthy subjects. METHODS: Eighteen untreated MtF subjects, 30 heterosexual males, 64 heterosexual females, and 42 homosexual males from university students/staff, at gay events, and in Gender Clinics were shown a composite male or female face. The sexual dimorphism of these pictures was stressed or reduced in a continuous fashion through an open-source morphing program with a sequence of 21 pictures of the same face warped from a feminized to a masculinized shape. MAIN OUTCOME MEASURES: An open-source morphing program (gtkmorph) based on the X-Morph algorithm. RESULTS: MtF GD subjects and heterosexual females showed the same pattern of preferences: a clear preference for less dimorphic (more feminized) faces for both short- and long-term relationships. Conversely, both heterosexual and homosexual men selected significantly much more dimorphic faces, showing a preference for hyperfeminized and hypermasculinized faces, respectively. CONCLUSIONS: These data show that the facial preferences of MtF GD individuals mirror those of the sex congruent with their gender identity. Conversely, heterosexual males trace the facial preferences of homosexual men, indicating that changes in sexual orientation do not substantially affect preference for the most attractive faces.


Assuntos
Identidade de Gênero , Heterossexualidade/psicologia , Homossexualidade Masculina/psicologia , Comportamento Sexual/psicologia , Adulto , Face , Feminino , Feminização , Humanos , Masculino , Adulto Jovem
16.
J Sex Med ; 11(3): 709-19, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24330520

RESUMO

INTRODUCTION: Cross-sex hormonal treatment (CHT) used for gender dysphoria (GD) could by itself affect well-being without the use of genital surgery; however, to date, there is a paucity of studies investigating the effects of CHT alone. AIMS: This study aimed to assess differences in body uneasiness and psychiatric symptoms between GD clients taking CHT and those not taking hormones (no CHT). A second aim was to assess whether length of CHT treatment and daily dose provided an explanation for levels of body uneasiness and psychiatric symptoms. METHODS: A consecutive series of 125 subjects meeting the criteria for GD who not had genital reassignment surgery were considered. MAIN OUTCOME MEASURES: Subjects were asked to complete the Body Uneasiness Test (BUT) to explore different areas of body-related psychopathology and the Symptom Checklist-90 Revised (SCL-90-R) to measure psychological state. In addition, data on daily hormone dose and length of hormonal treatment (androgens, estrogens, and/or antiandrogens) were collected through an analysis of medical records. RESULTS: Among the male-to-female (MtF) individuals, those using CHT reported less body uneasiness compared with individuals in the no-CHT group. No significant differences were observed between CHT and no-CHT groups in the female-to-male (FtM) sample. Also, no significant differences in SCL score were observed with regard to gender (MtF vs. FtM), hormone treatment (CHT vs. no-CHT), or the interaction of these two variables. Moreover, a two-step hierarchical regression showed that cumulative dose of estradiol (daily dose of estradiol times days of treatment) and cumulative dose of androgen blockers (daily dose of androgen blockers times days of treatment) predicted BUT score even after controlling for age, gender role, cosmetic surgery, and BMI. CONCLUSIONS: The differences observed between MtF and FtM individuals suggest that body-related uneasiness associated with GD may be effectively diminished with the administration of CHT even without the use of genital surgery for MtF clients. A discussion is provided on the importance of controlling both length and daily dose of treatment for the most effective impact on body uneasiness.


Assuntos
Imagem Corporal/psicologia , Identidade de Gênero , Hormônios Gonadais/administração & dosagem , Transtornos Mentais/psicologia , Transexualidade/tratamento farmacológico , Adulto , Idoso , Antagonistas de Androgênios/uso terapêutico , Androgênios/uso terapêutico , Estradiol/uso terapêutico , Estrogênios/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Comportamento Sexual/psicologia , Transexualidade/psicologia
17.
Chemistry ; 19(39): 12991-3001, 2013 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-23913577

RESUMO

A squaraine dye functionalized with a bulky trialkoxy phenyl moiety through a flexible diamide linkage (GA-SQ) capable of undergoing self-assembly has been synthesized and fully characterized. Rapid cooling of a hot solution of GA-SQ to 0 °C results in self-assembled precipitates consisting of two types of nanostructures, rings and ill-defined short fibers. The application of ultrasound modifies the conditions for the supersaturation-mediated nucleation, generating only one kind of nuclei and prompting the formation of crystalline fibrous structures, inducing gelation of solvent molecules. The unique self-assembling behavior of GA-SQ under ultrasound stimulus has been investigated in detail by using absorption, emission, FT-IR, XRD, SEM, AFM and TEM techniques. These studies reveal a nucleation growth mechanism of the self-assembled material, an aspect rarely scrutinized in the area of sonication-induced gelation. Furthermore, in order to probe the effects of nanoscale substrates on the sonication-induced self-assembly, a minuscule amount of single-walled carbon nanotubes was added, which leads to acceleration of the self-assembly through a heterogeneous nucleation process that ultimately affords a supramolecular gel with nanotape-like morphology. This study demonstrates that self-assembly of functional dyes can be judiciously manipulated by an external stimulus and can be further controlled by the addition of carbon nanotubes.

18.
J Sex Med ; 10(4): 1012-23, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23347389

RESUMO

INTRODUCTION: Subjects with gender identity disorder (GID) have been reported to be highly dissatisfied with their body, and it has been suggested that the body is their primary source of suffering. AIMS.: To evaluate quality and intensity of body uneasiness in GID subjects, comparing them with a sample of eating disorder patients and a control group. To detect similarities and differences between subgroups of GID subjects, on the basis of genotypic sex and transitional stage. METHODS: Fifty male-to-female (MtF) GID (25 without and 25 with genital reassignment surgery performed), 50 female-to-male (FtM) GID (28 without and 22 with genital reassignment surgery performed), 88 eating disorder subjects (26 anorexia nervosa, 26 bulimia nervosa, and 36 binge eating disorder), and 107 healthy subjects were evaluated. MAIN OUTCOME MEASURES: Subjects were studied by means of the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, the Symptom Checklist (SCL-90), and the Body Uneasiness Test (BUT). RESULTS: GID and controls reported lower psychiatric comorbidity and lower SCL-90 General Severity Index (GSI) scores than eating disorder subjects. GID MtF without genital reassignment surgery showed the highest BUT values, whereas GID FtM without genital reassignment surgery and eating disorder subjects showed higher values compared with both GID MtF and FtM who underwent genital reassignment surgery and controls. Considering BUT subscales, a different pattern of body uneasiness was observed in GID and eating disorder subjects. GID MtF and FtM without genital reassignment surgery showed the highest BUT GSI/SCL-90 GSI ratio compared with all the eating disorder groups. CONCLUSIONS: GID and eating disorders are characterized by a severe body uneasiness, which represents the core of distress in both conditions. Different dimensions of body uneasiness seem to be involved in GID subsamples, depending on reassignment stage and genotypic sex. In eating disorder subjects body uneasiness is primarily linked to general psychopathology, whereas in GID such a relationship is lacking.


Assuntos
Imagem Corporal/psicologia , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Identidade de Gênero , Transexualidade/psicologia , Adulto , Análise de Variância , Estudos de Casos e Controles , Estudos Transversais , Transtornos da Alimentação e da Ingestão de Alimentos/complicações , Feminino , Humanos , Masculino , Transtornos Mentais/complicações , Procedimentos de Readequação Sexual
19.
J Sex Med ; 10(2): 408-19, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23171237

RESUMO

INTRODUCTION: Male to female (MtFs) and female to male (FtMs) subjects with gender identity disorder (GID) seem to differ with regard to some sociodemographic and clinical features. Currently, no descriptive studies focusing on MtFs and FtMs attending an Italian clinic are available. AIM: To describe the sociodemographic characteristics of a GID population seeking assistance for gender transition and to assess possible differences in those features between MtFs and FtMs. METHODS: A consecutive series of 198 patients was evaluated for gender dysphoria from July 2008 to May 2011 in four dedicated centers. A total of 140 subjects (mean age 32.6 ± 9.0 years old) meeting the criteria for GID, with their informed consent and without genital reassignment surgery having already been performed, were considered (92 MtFs and 48 FtMs). Diagnosis was based on formal psychiatric classification criteria. MAIN OUTCOME MEASURES: Medical history and sociodemographic characteristics were investigated. Subjects were asked to complete the Body Uneasiness Test (a self-rating scale exploring different areas of body-related psychopathology), Symptom Checklist-90 Revised (a self-rating scale to measure psychological state), and the Bem Sex Role Inventory (a self-rating scale to evaluate gender role). The presence of psychiatric comorbidities was evaluated using the Structured Clinical Interviews for Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision (DSM-IV-TR) (SCID I and SCID II). RESULTS: Several significant differences were found between MtFs and FtMs regarding lifestyle and sociodemographic factors and in psychometric test scores. No differences were found in terms of psychiatric comorbidity. CONCLUSIONS: This is the first large study reporting the sociodemographic characteristics of a GID sample referring to Italian clinics, and it provides different profiles for MtFs and FtMs. In particular, FtMs display significantly better social functioning.


Assuntos
Identidade de Gênero , Transexualidade/diagnóstico , Transexualidade/epidemiologia , Adulto , Comorbidade , Estudos Transversais , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Humanos , Entrevista Psicológica , Itália , Estilo de Vida , Masculino , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Transtornos Mentais/psicologia , Psicometria/estatística & dados numéricos , Reprodutibilidade dos Testes , Autoavaliação (Psicologia) , Procedimentos de Readequação Sexual , Comportamento Sexual , Fatores Socioeconômicos , Inquéritos e Questionários , Transexualidade/psicologia , Adulto Jovem
20.
Sci Rep ; 13(1): 22733, 2023 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-38123639

RESUMO

Although once regarded as a unique human feature, tool-use is widespread in the animal kingdom. Some of the most proficient tool-users are our closest living relatives, chimpanzees. These repertoires however consist primarily of tool use, rather than tool manufacture (for later use). Furthermore, most populations of chimpanzees use organic materials, such as sticks and leaves, rather than stones as tools. This distinction may be partly ecological, but it is also important as chimpanzees are often used as models for the evolution of human material culture, the oldest traces of which consist of manufactured sharp stone tools (so-called "flakes"). Thus, examining the conditions (if any) under which chimpanzees may develop flake manufacture and use can provide insight into the drivers of these behaviours in our own lineage. Previous studies on non-human apes' ability to make and use flakes focused on enculturated apes, giving them full demonstrations of the behaviour immediately, without providing social information on the task in a stepwise manner. Here we tested naïve, captive chimpanzees (N = 4; three potentially enculturated and one unenculturated subject) in a social learning experimental paradigm to investigate whether enculturated and/or unenculturated chimpanzees would develop flake making and use after social information of various degrees (including a human demonstration) was provided in a scaffolded manner. Even though social learning opportunities were provided, neither the unenculturated subject nor any of the potentially enculturated subjects made or used flakes, in stark contrast to previous studies with enculturated apes. These data suggest that flake manufacture and use is outside of our tested group of captive chimpanzees' individual and social learning repertoires. It also suggests that high levels of enculturation alongside human demonstrations (and/or training) may be required before captive chimpanzees can develop this behaviour.


Assuntos
Pan troglodytes , Aprendizado Social , Animais , Humanos , Aprendizagem , Comportamento Animal , Comportamento Social
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