6,835 research outputs found
Fine scale depth regulation of invertebrate larvae around coastal fronts
Vertical migrations of zooplankters have been widely described, but their
active movements through shallow, highly dynamic water columns within the inner
shelf may be more complex and difficult to characterize. In this study,
invertebrate larvae, currents, and hydrographic variables were sampled at
different depths during and after the presence of fronts on three different
cruises off the southern coast of South Africa. Internal wave dynamics were
observed in the hydrographic data set but also through satellite imagery,
although strong surface convergent currents were absent and thermal
stratification was weak. During the first two cruises, fronts were more
conspicuous and they preceded strong onshore currents at depth which developed
with the rising tide. Vertical distributions of larvae changed accordingly,
with higher abundances at these deep layers once the front disappeared. The
third cruise was carried out during slack tides, the front was not conspicuous,
deep strong onshore currents did not occur afterward and larval distributions
did not change consistently through time. Overall, the vertical distributions
of many larval taxa matched the vertical profiles of shoreward currents and
multivariate analyses revealed that these flows structured the larval
community, which was neither influenced by temperature nor chlorophyll. Thus,
the ability to regulate active vertical positioning may enhance shoreward
advection and determine nearshore larval distributions
Effects of Short-Term Nicotine Deprivation on Delay Discounting Among Young, Experienced, Exclusive Ends Users: An Initial Study
Delay discounting describes how rapidly delayed rewards lose value as a function of delay and serves as one measure of impulsive decision-making. Nicotine deprivation among combustible cigarette smokers can increase delay discounting. We aimed to explore changes in discounting following nicotine deprivation among electronic nicotine delivery systems (ENDS) users. Thirty young adults (aged 18-24 years) that exclusively used ENDS participated in two laboratory sessions: one with vaping as usual and another after 16 hr of nicotine deprivation (biochemically assessed). At each session, participants completed a craving measure and three hypothetical delay discounting tasks presenting choices between small, immediate rewards and large, delayed ones (money-money; e-liquid-e-liquid; e-liquid-money). Craving for ENDS significantly increased during short-term nicotine deprivation relative to normal vaping. Delay discounting rates in the e-liquid now versus money later task increased (indicating a shift in preference for smaller, immediate rewards) following short-term nicotine deprivation relative to vaping as usual, but no changes were observed in the other two discounting tasks. Short-term nicotine deprivation increased the preference for smaller amounts of e-liquid delivered immediately over larger, monetary awards available after a delay in this first study of its kind. As similar preference shifts for drug now versus money later have been shown to be indicative of increased desire to use drug as well as relapse risk, the findings support the utility of the current model as a platform to explore interventions that can mitigate these preference shifts. (PsycInfo Database Record (c) 2023 APA, all rights reserved)
Insights from behavioral economics to characterize substance use involvement in adolescents: a cluster analysis
Reinforcement pathology (RP), a framework rooted in behavioral economics, has contributed to advances in the etiology and treatment of substance
use. Drug demand and delay discounting (DD) have gained considerable interest, as they inform on the risk for escalation to substance use as well as
treatment-specific targets. No prior study conducted in Spain has explored the interplay of demand and DD in adolescents. This study was aimed to: 1)
identify whether DD and alcohol demand can yield empirically driven subgroups, and 2) examine differences in substance use involvement. The sample
comprised 107 (% females = 54.2) adolescents (M=15.46, SD=1.25) from a high school in Asturias (Spain). Participants filled out an ad-hoc survey
on substance use over the prior 30 days and one year. A 20-item alcohol purchase task (APT) was used to assess the reinforcing value of alcohol. The
21-item Monetary Choice Questionnaire evaluated impulsive choice. Two subgroups emerged: Cluster 1 (n = 72) and Cluster 2 (n = 35). Participants in
C2 consistently showed higher impulsivity and demand for alcohol, signifying lower responsiveness to alcohol pricing. As compared to C1, those in C2
had a higher prevalence of past-month substance use [C1: 26/72 (36.1%) vs. C2: 33/35 (94.3%), p <.001], and a greater frequency of drunkenness
[p <.001] and binge drinking episodes [p <.001]. RP differentiate between subgroups of adolescent substance users with patterns of more versus less
substance use involvement. The existence of specific drug use subpopulations should be considered when designing environmental preventive policiesLa economía conductual para caracterizar el uso de drogas en adolescentes: análisis de cluster. La patología del refuerzo (PR), basada en la economía
conductual, ha contribuido al avance de la etiología y el tratamiento de drogas. La demanda y el descuento por demora (DD) informan sobre el incremento
en el consumo y los objetivos de tratamiento. Ningún estudio realizado en España ha examinado la interacción entre ambas variables en adolescentes.
Los objetivos fueron: 1) identificar si el DD y la demanda de alcohol pueden identificar distintos subgrupos y, 2) examinar sus diferencias en el consumo
de sustancias. La muestra incluyó 107 (% mujeres = 54,2) adolescentes (M =15,46, DT =1,25) de enseñanza obligatoria en Asturias (España). Se evaluó
el consumo de drogas en los últimos 30 días y el último año. El poder reforzante del alcohol se evaluó mediante una tarea de compra de 20 ítems (APT).
La toma de decisiones impulsiva se evaluó mediante el Cuestionario de Elección Monetaria. Se identificaron dos subgrupos: Grupo 1 (n = 72) y Grupo
2 (n = 35). El Grupo 2 mostró una demanda e impulsividad más elevada, indicando menor sensibilidad a incrementos en el precio. Comparado con el
Grupo 1, el 2 obtuvo una prevalencia más elevada de consumo en el último mes [G1: 26/72 (36,1%) vs. G2: 33/35 (94,3%), p <,001], mayor frecuencia
de borracheras (p <,001) y episodios de consumo intensivo de alcohol (p <,001). La PR permite caracterizar e identificar grupos con distintos patrones
de consumo de sustancias. La existencia de distintos perfiles debería ser considerada a la hora de desarrollar políticas preventiva
Contingency management effects on delay discounting among patients receiving smoking cessation treatment
Antecedentes: la evidencia sugiere que el descuento por demora puede cambiar tras recibir intervenciones eficaces. No obstante, estudios previos que evaluaron el efecto del manejo de contingencias (MC) sobre el descuento por demora son escasos y presentan resultados mixtos. Se evaluó si el MC combinado con tratamiento cognitivo-conductual (TCC) para dejar de fumar se asoció con cambios en el descuento por demora al final del tratamiento y a los seis de seguimiento comparado con TCC. Método: Ciento dieciséis fumadores fueron asignados aleatoriamente a MC+TCC (n = 69) o a TCC solo (n = 47). Completaron la tarea de descuento por demora en la línea base, al final del tratamiento y a los seis meses de seguimiento. Evaluamos el efecto del MC en el descuento por demora con métodos paramétricos y no paramétricos. Resultados: Los análisis entre-grupos mostraron que ninguno de los tratamientos modificó el descuento por demora al final del tratamiento y a los seis meses de seguimiento. No obstante, algunos análisis intra-grupos mostraron que la condición de MC + TCC evidenció cierta reducción. Conclusiones: una intervención de MC no se asocia robustamente con cambios en el descuento por demora. Futuros estudios han de abordar qué tratamientos pueden modificarlo
iLIR : a web resource for prediction of Atg8-family interacting proteins
Macroautophagy was initially considered to be a nonselective process for bulk breakdown of cytosolic material. However, recent evidence points toward a selective mode of autophagy mediated by the so-called selective autophagy receptors (SARs). SARs act by recognizing and sorting diverse cargo substrates (e.g., proteins, organelles, pathogens) to the autophagic machinery. Known SARs are characterized by a short linear sequence motif (LIR-, LRS-, or AIM-motif) responsible for the interaction between SARs and proteins of the Atg8 family. Interestingly, many LIR-containing proteins (LIRCPs) are also involved in autophagosome formation and maturation and a few of them in regulating signaling pathways. Despite recent research efforts to experimentally identify LIRCPs, only a few dozen of this class of—often unrelated—proteins have been characterized so far using tedious cell biological, biochemical, and crystallographic approaches. The availability of an ever-increasing number of complete eukaryotic genomes provides a grand challenge for characterizing novel LIRCPs throughout the eukaryotes. Along these lines, we developed iLIR, a freely available web resource, which provides in silico tools for assisting the identification of novel LIRCPs. Given an amino acid sequence as input, iLIR searches for instances of short sequences compliant with a refined sensitive regular expression pattern of the extended LIR motif (xLIR-motif) and retrieves characterized protein domains from the SMART database for the query. Additionally, iLIR scores xLIRs against a custom position-specific scoring matrix (PSSM) and identifies potentially disordered subsequences with protein interaction potential overlapping with detected xLIR-motifs. Here we demonstrate that proteins satisfying these criteria make good LIRCP candidates for further experimental verification. Domain architecture is displayed in an informative graphic, and detailed results are also available in tabular form. We anticipate that iLIR will assist with elucidating the full complement of LIRCPs in eukaryotes
The forgotten mothers of extremely preterm babies : A qualitative study
© 2019 The Authors. Journal of Clinical Nursing Published by John Wiley & Sons LtdAims and objectives: To explore the experiences of mothers of extremely prematurebabies during their Neonatal Intensive Care Unit stay and transition home. Background: Mothers of extremely preterm infants (28 weeks’ gestation or less) experience a continuum of regular and repeated stressful and traumatic events, during the perinatal period, during the Neonatal Intensive Care Unit stay, and during transition home. Method: An interpretive description method guided this study. Ten mothers of extremely premature infants who had been at home for less than six months were recruited via a Facebook invitation to participate in semi‐structured telephone interviews exploring their experiences in the Neonatal Intensive Care Unit and the transition home. The data were examined using a six‐phase thematic analysis approach. The COREQ checklist has been used. Results: Two main themes emerged: (a) things got a bit dire; and (b) feeling a failure as a mother. Participants had a heightened risk of developing a mental disorder from exposure to multiple risk factors prior to and during birth, as well as during the postnatal period in the Neonatal Intensive Care Unit and their infant's transition to home. Mothers highlighted the minimal support for their mental health from healthcare professionals, despite their regular and repeated experience of traumatic events. Conclusion: The mothers were at high risk of developing post‐traumatic stress symptoms and/or other mental health issues. Of note, study participants relived the trauma of witnessing their infant in the Neonatal Intensive Care Unit, demonstrated hypervigilance behaviour and identified lack of relevant support needed when their infant was at home. Relevance to Clinical Practice: This study highlights the need for nurses to include a focus on the mothers’ psychosocial needs. Supporting maternal mental health both improves maternal well‐being and enables mothers to be emotionally available and responsive to their extremely preterm infant.Peer reviewe
Autophagosomal Protein Dynamics and Influenza Virus Infection
Autophagy is a constitutive, catabolic process leading to the lysosomal degradation of cytosolic proteins and organelles. However, it is also induced under stress conditions, remodeling the eukaryotic cell by regulating energy, protein, and lipid homeostasis. It is likely that the autophagosomal/lysosomal pathway evolved primordially to recycle cell components, but further functionally developed as to become part of the immune system to defend against invading pathogens. Likewise, pathogenic, foreign agents developed strategies to fight back and even to employ the autophagy machinery to their own benefit. Hence, the regulation of autophagy has many implications on human health and disease. This review summarizes the molecular dynamics of autophagosome formation, maturation, and target selection. Membrane dynamics, as well as protein–protein and protein–membrane interactions are particularly addressed. In addition, it recapitulates current knowledge of the influences of influenza virus infection on the process
- …