Poverty, displacement, and parental stress represent potent sources of early life stress (ELS). Stress disproportionately affects females, who are at increased risk for stress-related pathologies ...associated with cognitive impairment. Mechanisms underlying stress-associated cognitive impairment and enhanced risk of females remain unknown. Here, ELS is associated with impaired rule-reversal (RR) learning in females, but not males. Impaired performance was associated with decreased expression and density of interneurons expressing parvalbumin (PV+) in orbitofrontal cortex (OFC), but not other interneuron subtypes. Optogenetic silencing of PV+ interneuron activity in OFC of control mice phenocopied RR learning deficits observed in ELS females. Localization of reversal learning deficits to PV+ interneurons in OFC was confirmed by optogenetic studies in which neurons in medial prefrontal cortex (mPFC) were silenced and associated with select deficits in rule-shift learning. Sex-, cell-, and region-specific effects show altered PV+ interneuron development can be a driver of sex differences in cognitive dysfunction.
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•Early life stress leads to select deficits in reversal learning in female mice•Impaired rule-reversal learning is associated with decreased PV and GAD67 in OFC•Optogenetic silencing of OFC PV+ cells recapitulates ELS effects on reversal learning•Optogenetic silencing of mPFC PV+ cells impairs rule shifting, but not reversal learning
Goodwill et al. investigate the effect of early life stress (ELS) on cognitive development in a mouse model. Using a combination of genetic, histological, optogenetic, and behavioral techniques, they find that ELS leads to female-selective impairments in the ability to engage in rule reversal, but not other forms of attentional learning. Impairments are associated with diminished parvalbumin (PV) expression and a decreased density of PV+ interneurons in the orbitofrontal cortex (OFC).
Canonically, action potentials of most mammalian neurons initiate at the axon initial segment (AIS) and propagate bidirectionally: orthodromically along the distal axon and retrogradely into the soma ...and dendrites. Under some circumstances, action potentials may initiate ectopically, at sites distal to the AIS, and propagate antidromically along the axon. These "ectopic action potentials" (EAPs) have been observed in experimental models of seizures and chronic pain, and more rarely in nonpathological forebrain neurons. Here we report that a large majority of parvalbumin-expressing (PV+) interneurons in the upper layers of mouse neocortex, from both orbitofrontal and primary somatosensory areas, fire EAPs after sufficient activation of their somata. Somatostatin-expressing interneurons also fire EAPs, though less robustly. Ectopic firing in PV+ cells occurs in varying temporal patterns and can persist for several seconds. PV+ cells evoke strong synaptic inhibition in pyramidal neurons and interneurons and play critical roles in cortical function. Our results suggest that ectopic spiking of PV+ interneurons is common and may contribute to both normal and pathological network functions of the neocortex.
Male Xenopus laevis frogs have been observed to clasp other males in a sustained, amplectant position, the purpose of which is unknown. We examined three possible hypotheses for this ...counter-intuitive behavior: 1) clasping males fail to discriminate the sex of the frogs they clasp; 2) male-male clasping is an aggressive or dominant behavior; or 3) that males clasp other males to gain proximity to breeding events and possibly engage in sperm competition. Our data, gathered through a series of behavioral experiments in the laboratory, refute the first two hypotheses. We found that males did not clasp indiscriminately, but showed a sex preference, with most males preferentially clasping a female, but a proportion preferentially clasping another male. Males that clasped another male when there was no female present were less likely to "win" reproductive access in a male-male-female triad, indicating that they did not establish dominance through clasping. However, those males did gain proximity to oviposition by continued male-male clasping in the presence of the female. Thus, our findings are consistent with, but cannot confirm, the third hypothesis of male-male clasping as an alternative reproductive tactic.
► Empirical test of key hypotheses regarding covert networks. ► Supports claims that covert networks tend to be sparse and decentralised. ► But suggests this may be compensated for by dense local ...clustering. ► Challenges claim that covert networks rely upon pre-existing ties. ► Introduces a new and important case study to research on covert networks.
This paper formulates and empirically tests a number of hypotheses regarding the impact of covertness upon network structure. Specifically, hypotheses are deduced from theoretical arguments regarding a ‘secrecy-efficiency trade off’ which is said to shape covert networks. The paper draws upon data concerning the UK suffragettes. It is taken from a publicly archived UK Home Office document listing 1992 court appearances (for suffrage related activities), involving 1214 individuals and 394 court sessions, between 1906 and 1914. Network structure at earlier phases of suffragette activism, when the movement was less covert, is compared with that during the final phase, when it was more covert and meets the definitional criteria of what we call a ‘covert social movement network’ (CSMN). Support for the various hypotheses tested is variable but the key claims derived from the idea of the secrecy-efficiency trade off are supported. Specifically, the suffragettes’ network becomes less dense and less degree centralised as it becomes more covert.
We present results from a wide-field imaging campaign at the Canada-France-Hawaii Telescope to study the spectacular outburst of comet 17P/Holmes in late 2007. Using image-processing techniques we ...probe inside the spherical dust coma and find 16 fragments having both spatial distribution and kinematics consistent with isotropic ejection from the nucleus. Photometry of the fragments is inconsistent with scattering from monolithic, inert bodies. Instead, each detected fragment appears to be an active cometesimal producing its own dust coma. By scaling from the coma of the primary nucleus of 17P/Holmes, assumed to be 1.7 km in radius, we infer that the 16 fragments have maximum effective radii between ~10 m and ~100 m on UT 2007 November 6. The fragments subsequently fade at a common rate of ~0.2 mag day--1, consistent with steady depletion of ices from these bodies in the heat of the Sun. Our characterization of the fragments supports the hypothesis that a large piece of material broke away from the nucleus and crumbled, expelling smaller, icy shards into the larger dust coma around the nucleus.
Heat stress (HS), immune challenges (IC) and pecking behavior are some of the many stressors poultry can experience in commercial settings that may affect bird welfare and meat quality after harvest. ...The first objective was to determine if HS or IC turkeys displayed greater negative effects on meat quality, and the second objective was to determine if the frequency of non-aggressive pecking behaviors among the birds was related to meat quality. Ninety-two, commercial male, beak-trimmed turkeys were used with a total of 15 rooms and 4–7 birds per room. Each treatment was applied for 1 week prior to harvest: the Control (CON) group had no stressors added, the HS group ambient temperature was approximately 29 °C for 120 min, and the IC group involved inoculating birds with a live vaccine for hemorrhagic enteritis virus. Birds were recorded and scored to quantify pecking behavior. Once harvested, carcasses were evaluated for feather retention force, pH, color, proximate analysis, fatty acid composition, shear force, and drip loss. Stress treatment resulted in HS breasts having the lowest protein content, and IC breasts having the lowest CIE L* values and the greatest shear force values. Pecking behavior had no impact on any meat quality attributes.
Accelerometers have the potential to provide objective, non-invasive methods for detecting changes in animal behavior and health. Our objectives were to: (1) determine the effects of ...micro-acceleration data loggers (accelerometers) and habituation to accelerometers on turkey gait and health status, (2) determine age-related changes in gait and health status, and (3) assess the validity and reliability of the accelerometers. Thirty-six male commercial turkeys were randomly assigned to one of five groups: accelerometer and habituation period (AH), accelerometer and no habituation period (AN), VetRap bandage (no accelerometer) and habituation period (VH), bandage (no accelerometer) and no habituation period (VN), and nothing on either leg (C). Health status and body condition were assessed prior to video-recording birds as they walked across a Tekscan® pressure pad at 8, 12, and 16 weeks to determine effects of treatment on number of steps, cadence, gait time, gait distance, gait velocity, impulse, gait cycle time, maximum force, peak vertical pressure, single support time, contact time, step length, step time, step velocity, stride length, total double support time, and duty factor. Accelerometer validity and reliability were determined by comparing the number of steps detected by the accelerometer to the number of steps determined from video recordings. Several age-related changes in turkey gait were found regardless of habituation including a slower cadence at 16 weeks, shorter gait distance at 8 weeks, and slower gait velocity at 16 weeks. When comparing bandaged vs. unbandaged limbs, both treatment and age-treatment interactions were found depending on the gait parameter. Accelerometer validity and reliability were affected by both age and treatment. False discovery rate increased, while accuracy and specificity decreased with age. Validity and reliability were lowest for non-habituated birds (AN and VN). Results demonstrated that micro-data loggers do not adversely affect turkey health status, but habituation to wearing accelerometers greatly affects accelerometer reliability and validity. Accelerometer validity and turkey gait are also greatly affected by the age of the turkeys.
Background
People in the criminal justice system have complex needs but often do not make use of services outside of prison, in many cases due to poorly joined up working between health and criminal ...justice services. The ‘Engager’ programme aimed to develop a complex collaborative care intervention for people leaving prison with common mental health problems that could support their transition into the community and facilitate joined up working between health, justice and social services. To augment our core intervention theory, we wanted to learn from innovative and forward-thinking services providing interagency support and/or treatment for people experiencing common mental health problems within the criminal justice system. We wanted to identify key elements of interagency practice to understand what was and was not effective in engaging people, maintaining their contact and improving mental health and other aspects of their lives.
Method
We used a multiple case study design with a focused ethnographic approach in four study sites. Data came from three sources (documents, field notes and semi-structured interviews) underwent a framework analysis.
Results
We identified seven main themes, namely: collaboration, client engagement, client motivation, supervision, therapeutic approach, peers and preparations for ending. Engaging and motivating clients was dependent on the relationship built with the professional. This relationship was developed through building trust and rapport, which required time and respectful, open and honest communication. Professionals were often unable to build this relationship effectively if they did not work in effective interagency collaborations, particularly those which included shared practices and were supported by effective supervision.
Conclusions
The multiple case study design contributed insights as to how health and justice services work together. The main themes identified are well known factors in health and justice co-working. However, the novel insights were gleaned examining interdependence and interactions in complex, multifactorial phenomena and practice, in particular the importance of shared practice and supervision models. The approach of selecting a small number of cases representing identified knowledge gaps contributed a valuable addition to the program theory and delivery for an innovative complex intervention.