Critical aggregation concentration and reversibility of amyloid-β (1-40) oligomers.

Amyloid-beta (Aβ) aggregation is a critical factor in the pathogenesis of Alzheimer's disease, with distinct aggregation behaviours observed between its isoforms Amyloid-β 1-40 (Aβ40) and 1-42 (Aβ42). In this study, we investigated the aggregation properties of Aβ40 using fluorescence correlation spectroscopy (FCS) and detailed data analysis. Our results reveal that Aβ40 undergoes a two-step cooperative aggregation process.

Validating the Enright Forgiveness Inventory in Ecuador.

Research on forgiveness is limited in Ecuador. This study validated the Enright Forgiveness Inventory-30 (EFI-30) among 960 participants in Ecuador, resulting in robust reliability and validity values. Our findings provide avenues for future research and practices.

Supramolecular association studied by Fluorescence correlation spectroscopy.

A comprehensive description of a supramolecular system involves a full understanding of its thermodynamic and dynamic properties, as well as detailed knowledge of its structure. Fluorescence Correlation Spectroscopy (FCS) constitutes a powerful technique to acquire this information. Fluorescence correlation curves show a characteristic diffusion term that is related to the binding equilibrium constant or other thermodynamic properties of the supramolecular system.

Estimating the Psychological Harm Consequence of Bullying Victimization: A Meta-Analytic Review for Forensic Evaluation.

Unlabelled: The prevalence of traditional bullying victimization has been estimated at around 36%, while that of cyberbullying has been estimated at 15%. The victimization of bullying brings with it harm to mental health that must be compensated for, after a forensic evaluation, by the aggressor or legal guardian. Thus, a meta-analytic review was undertaken with the aim of knowing the effect of bullying victimization on psychological harm, as well as quantifying the magnitude of the harm and estimating the probability that no harm associated with bullying victimization is generated.

Early Aggregation of Amyloid-β(1-42) Studied by Fluorescence Correlation Spectroscopy.

Alzheimer's disease (AD) is a progressive neurodegenerative disease affecting cognitive and memory abilities and is believed to be linked to the formation and accumulation of neurotoxic aggregates of the Amyloid-β peptide (Aβ). In particular, it is the formation of soluble pre-fibrillar oligomers within the early stage of Aβ aggregation which is thought to represent a key step in the development of AD, thus underlining the interest in characterizing the aggregation process and the nature of these aggregates. In this context, fluorescence correlation spectroscopy (FCS) has emerged as a valuable alternative for the study of these systems in solution.

Study of informal reasoning in judicial agents in sexual aggression cases.

Background/objective: Judicial decisions must rest on formal reasoning. Nevertheless, informal reasoning sources (cognitive and motivational biases) were observed in judicial judgment making. Literature has identified sexual aggression cases as the most favorable for informal reasoning.

Spectroscopic Characterization of Mitochondrial G-Quadruplexes.

Guanine quadruplexes (G4s) are highly polymorphic four-stranded structures formed within guanine-rich DNA and RNA sequences that play a crucial role in biological processes. The recent discovery of the first G4 structures within mitochondrial DNA has led to a small revolution in the field. In particular, the G-rich conserved sequence block II (CSB II) can form different types of G4s that are thought to play a crucial role in replication.

A Surfactant Concentration Model for the Systematic Determination of the Critical Micellar Concentration and the Transition Width.

The critical micellar concentration () is a fundamental property of surfactant solutions. Many proposed methods for the definition and determination of the from property-concentration plots yield values, which depend on the studied property, on the specific technique used for its analysis and in many cases on the subjective choice of the chosen type of plot and concentration interval. In this focus review, we revise the application of a surfactant concentration model we proposed earlier that defines the directly based on the surfactant concentration.

Adolescent-to-Parent Violence: Psychological and Family Adjustment.

Adolescent-to-Parent Violence (APV) or Child-to-Parent Violence (CPV) is a specific form of violence that has remained inconspicuous until recently, but is becoming a mounting social issue and is increasingly the focus of scientific research. Of the variables related to APV, the study assessed the characteristics of the family system and its relationship to the psychosocial adjustment of adolescents, an aspect scarcely examined in the literature. Thus, a field study was performed on a community sample of 210 adolescents aged 12-17 years (51.

Unveiling the multi-step solubilization mechanism of sub-micron size vesicles by detergents.

The solubilization of membranes by detergents is critical for many technological applications and has become widely used in biochemistry research to induce cell rupture, extract cell constituents, and to purify, reconstitute and crystallize membrane proteins. The thermodynamic details of solubilization have been extensively investigated, but the kinetic aspects remain poorly understood. Here we used a combination of single-vesicle Förster resonance energy transfer (svFRET), fluorescence correlation spectroscopy and quartz-crystal microbalance with dissipation monitoring to access the real-time kinetics and elementary solubilization steps of sub-micron sized vesicles, which are inaccessible by conventional diffraction-limited optical methods.

Assessing the effects of an education program on mental health problems in separated parents.

Background: Parental separation is a stressful experience that can lead to parents suffering mental health problems (MHPs). Parental separation education programs for coping with post-separation adjustment have proven to be effective in reducing conflict and improving co-parenting. However, the effects of these programs on MHPs have not been assessed.

Critical aggregation concentration for the formation of early Amyloid-β (1-42) oligomers.

The oligomers formed during the early steps of amyloid aggregation are thought to be responsible for the neurotoxic damage associated with Alzheimer's disease. It is therefore of great interest to characterize this early aggregation process and the aggregates formed, especially for the most significant peptide in amyloid fibrils, Amyloid-β(1-42) (Aβ42). For this purpose, we directly monitored the changes in size and concentration of initially monomeric Aβ42 samples, using Fluorescence Correlation Spectroscopy.

What and How Much Do Children Lose in Academic Settings Owing to Parental Separation?

The literature has firmly established an association between parental separation and school failure. Nevertheless, parental separation does not affect academic aptitudes. Thus, mediators explain such relationship.

A meta-analytic review of the MMPI validity scales and indexes to detect defensiveness in custody evaluations.

: In child custody disputes, one of the remit of the forensic psychologist is to evaluate parental attributes while suspecting defensiveness. The instrument of choice for undertaking this double task is the MMPI. : As to establish the state of the art on this, a meta-analysis was undertaken with a total of 32 primary studies from which 256 effect sizes were assessed.

Estimating the Epidemiology and Quantifying the Damages of Parental Separation in Children and Adolescents.

Parental separation is linked to multiple negative outcomes for children in all spheres of life. A field study was designed to estimate the epidemiology and to quantify the outcomes on the wellbeing of children from separated parents. Thus, data on socio-economic status, psychological adjustment, behavioral disorders, social relations, self-concept, and academic achievement were gathered from 346 children and adolescents, 173 separated parents, and 173 parents from intact families in the paediatric catchment area of Galicia (Spain).

Towards ratiometric sensing of amyloid fibrils in vitro.

The aggregation of amyloid-β peptide and its accumulation in the human brain has an important role in the etiology of Alzheimer's disease. Thioflavin T has been widely used as a fluorescent marker for these amyloid aggregates. Nevertheless, its complex photophysical behavior, with strong wavelength dependencies of all its fluorescence properties, requires searching for new fluorescent probes.

Fluorescence emission of pyrene in surfactant solutions.

The systematic description of the complex photophysical behaviour of pyrene in surfactant solutions in combination with a quantitative model for the surfactant concentrations reproduces with high accuracy the steady-state and the time resolved fluorescence intensity of pyrene in surfactant solutions near the cmc, both in the monomer and in the excimer emission bands. We present concise model equations that can be used for the analysis of the pyrene fluorescence intensity in order to estimate fundamental parameters of the pyrene-surfactant system, such as the binding equilibrium constant K of pyrene to a given surfactant micelle, the rate constant of excimer formation in micelles, and the equilibrium constant of pyrene-surfactant quenching. The values of the binding equilibrium constant K(TX100)=3300·10³ M⁻¹ and K(SDS)=190·10³ M⁻¹ for Triton X-100 (TX100) and SDS micelles, respectively, show that the partition of pyrene between bulk water and micelles cannot be ignored, even at relatively high surfactant concentrations above the cmc.

Fluorescence-labeled bis-benzamidines as fluorogenic DNA minor-groove binders: photophysics and binding dynamics.

In recent decades there has been great interest in the design of highly sensitive sequence-specific DNA binders. The eligibility of the binder depends on the magnitude of the fluorescence increase upon binding, related to its photophysics, and on its affinity and specificity, which is, in turn, determined by the dynamics of the binding process. Therefore, progress in the design of DNA binders requires both thorough photophysical studies and precise determination of the association and dissociation rate constants involved.

Assessing Impression Management With the MMPI-2 in Child Custody Litigation.

Forensic psychological evaluation of parents in child custody litigation is primarily focused on evaluating parenting capacity and underreporting. The biased responses of underreporting have been classified as Impression Management (IM) or as Self-Deceptive Positivity (S-DP), which are regarded to be conscious or unconscious in nature, respectively. A field study was undertaken to assess impression management on the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) in child custody cases, the accuracy of the MMPI-2 scales in classifying IM, and what parents in child custody litigation actually manipulate in terms of IM.

Assessment of the standard forensic procedure for the evaluation of psychological injury in intimate-partner violence.

In judicial terms, a victim refers to any person who has suffered injury arising from an action or omission of an action that constitutes an offence, and the burden of proof lies with the prosecution. A review of Spanish judicial judgements underscored that the lack of evidence of psychological injury in cases of intimate-partner violence (IPV) accounted for approximately 40% of acquittals. Thus, the Spanish standard of proof for the forensic evaluation of psychological injury i.

Quick adjustment of imaging tracer payload, for in vivo applications of theranostic nanostructures in the brain.

Unlabelled: In order to provide sufficient sensibility for detection, selection of an adequate payload of imaging probe is critical, during the design of MRI theranostic nanoplatforms. This fact is particularly crucial for in vivo applications in the brain, where delivery of macromolecules is limited by the blood-brain barrier. Here we report a simple and quick process for the estimation of adequate payloads of gadolinium in liposomes with potential to act as theranostic agents, for in vivo MRI applications in the brain.

A model for monomer and micellar concentrations in surfactant solutions: application to conductivity, NMR, diffusion, and surface tension data.

An empirical model for the concentrations of monomeric and micellized surfactants in solution is presented as a consistent approach for the quantitative analysis of data obtained with different experimental techniques from surfactant solutions. The concentration model provides an objective definition of the critical micelle concentration (cmc) and yields precise and well defined values of derived physical parameters. The use of a general concentration model eliminates subjective graphical procedures, reduces methodological differences, and thus allows one to compare directly the results of different techniques or to perform global fits.

Role of electrostatic and hydrophobic forces in the interaction of ionic dyes with charged micelles.

The nature and strength of the interactions between a cationic fluorophore, Rhodamine 123 (R123), and surfactants of different head charge are investigated. Series of absorption and fluorescence emission spectra and of fluorescence decays are measured. R123 does not interact with the monomers of both nonionic and cationic surfactants but it presents affinity to their micelles.

Host-guest complexation studied by fluorescence correlation spectroscopy: adamantane-cyclodextrin inclusion.

The host-guest complexation between an Alexa 488 labelled adamantane derivative and beta-cyclodextrin is studied by Fluorescence Correlation Spectroscopy (FCS). A 1:1 complex stoichiometry and a high association equilibrium constant of K = 5.2 x 10(4) M(-1) are obtained in aqueous solution at 25 degrees C and pH = 6.