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Zusammenfassung Hintergrund Demografische Veränderungen bewirken einen steilen Anstieg der Anzahl der über 65-Jährigen. Damit verbunden ist die Zunahme der Anzahl pflegebedürftiger, multimorbid Erkrankter. National wie auch international gibt es keine Informationen insbesondere zur Versorgung von Psoriasiserkrankten im Setting Pflegeheim und zur Frage, wie diese durch den Eintritt in ein Pflegeheim beeinflusst wird. Fragestellung Ziel war es, anhand von Interviews bzw. Fokusgruppen die Ergebnisse vorausgehender Routinedatenanalysen zur Versorgung Psoriasiserkrankter in Pflegeheimen mit medizinischen Versorgern (Dermatologen, Allgemeinmediziner, Pflegedienstleitungen und Pflegekräfte) zu diskutieren, Schwierigkeiten der Versorgung aufzudecken und abschließend Handlungsempfehlungen für eine zukunftsfähige gerontodermatologische Versorgung abzuleiten. Material und Methoden Durchgeführt wurden qualitative Leitfaden-gestützte Interviews und Fokusgruppen mit Dermatologen (n = 5), Allgemeinmedizinern (n = 7), Pflegekräften (n = 7) und Pflegedienstleitungen (n = 2). Die Daten wurden inhaltsanalytisch ausgewertet. Ergebnisse Die Auswertung ergab insgesamt 344 Aussagen, die insgesamt 14 Hauptkategorien zugeordnet werden konnten. Die Ergebnisse zeigen, dass für die Versorgungsqualität von Menschen mit Hautkrankheiten, insbesondere Psoriasis, in Pflegeinrichtungen ein Verbesserungsbedarf besteht. Dieser zeigt sich sowohl auf ärztlicher als auch auf pflegerischer Ebene. Laut der Versorger (N = 21) kann dies insbesondere durch eine verstärkte digitale Versorgung, dermatologische Schulungen für Hausärzte und Pflegefachkräfte sowie engere Kooperationen zwischen den einzelnen Disziplinen adressiert werden. Schlussfolgerung Digitale Pflegekonsile, aber auch eine spezifische Leitlinie zur „Haut des alternden Menschen“ können von Nutzen sein, um die dermatologische Versorgungssituation im Pflegeheim zu verbessern und somit das Wohlbefinden der Betroffenen zu steigern.

One important factor contributing to age-related memory decline is the loss of distinctiveness with which information is represented in brain activity. This loss in neural selectivity may be driven by neural attenuation (i.e., reduced activation to target stimuli) or neural broadening (i.e., increased activation to non-target stimuli). In this fMRI study, we assessed age differences in neural selectivity during first encoding, repeated encoding, and recognition, as well as the underlying pattern (broadening versus attenuation). We found lower neural selectivity in older compared to younger adults during all memory stages. Crucially, while reduced selectivity in older adults was due to neural broadening during first encoding, it was driven by neural attenuation during recognition, but revealed no clear pattern during repeated encoding. Our findings suggest that intrinsic differences between memory stages may interact with neural activity to manifest as either neural broadening or attenuation. Moreover, despite these differential patterns, neural selectivity was highly correlated across memory stages, indicating that one common mechanism may underly distinct expressions of age-related neural dedifferentiation.

Long-standing theories of cognitive aging suggest that memory decline is associated with age-related differences in the way information is represented in the brain. In the last years, these hypotheses have been substantiated by novel neuroscientific evidence that was derived from multivariate pattern similarity analyses. This approach enabled researchers to take a representational perspective on brain and cognition, and allowed them to study the properties of neural representations that support successful episodic memory. In young adults, two prominent representational properties have been identified as crucial for memory performance, namely the distinctiveness and the stability of neural representations. Distinctiveness describes the relation of neural representations to each other, i.e., how similar or dissimilar they are, while stability characterizes how much or how little representations change over time. However, researchers have only recently started to explore age differences in these representational properties and how they interact to support episodic memory in old age. Here, we review studies that used multivariate analysis tools for different neuroimaging techniques to clarify how representational distinctiveness, stability, and their interactions relate to memory performance across adulthood, and specifically during aging. While most evidence on age differences in neural representations involved how stimulus category information is represented, recent studies demonstrated that particularly item-level stability and specificity of activity patterns are positively linked to memory success and decline during aging. Overall, multivariate methods offer a promising and versatile tool for our understanding of age differences in the neural representations underlying episodic memory.

Substance misuse during pregnancy can be harmful to the health of both mothers and infants. Existing recovery services or prenatal care for pregnant women with substance use disorders (SUD) in the U.S. and other countries typically fall short in providing the necessary specialized care women with SUDs need. Disclosure of substance misuse is one key factor in gaining access to specialized prenatal care; yet, barriers such as social stigma and internal shame and guilt lead many women to under-report any substance misuse during their pregnancy. This study sought to understand the process of how and why pregnant women with SUDs choose to disclose or not disclose their substance misuse to their providers when seeking prenatal care. Data were collected through interviews with N = 21 women with SUDs in the northeast U.S. whose young children had been exposed to opioids, cocaine, or MAT in utero. Thematic, inductive analysis using line-by-line coding was conducted to understand the perspectives of the women. The women’s narratives suggested a clear tension regarding whether to disclose their substance misuse to any providers during their pregnancy. Four themes describing the process of disclosure or non-disclosure were found, including reasons for and ways of being secret or choosing to disclose their substance misuse during pregnancy. The centrality of shame, guilt, and stigma regarding substance misuse must be addressed by medical and mental health providers in order to increase disclosure and improve access to care for women with SUDs.

Undernutrition impairs reproductive success through suppression of gonadotropin-releasing hormone (GnRH), and subsequently luteinizing hormone (LH), secretion. Given that kisspeptin and neurokinin B (NKB) neurons in the arcuate nucleus (ARC) of the hypothalamus are thought to play key stimulatory roles in the generation of GnRH/LH pulses, we hypothesized that feed restriction would reduce the ARC mRNA abundance and protein expression of kisspeptin and NKB in young, male sheep. Fourteen wethers (castrated male sheep five months of age) were either fed to maintain (FM; n = 6) pre-study body weight or feed-restricted (FR; n = 8) to lose 20% of pre-study body weight over 13 weeks. Throughout the study, weekly blood samples were collected and assessed for LH concentration using RIA. At Week 13 of the experiment, animals were killed, heads were perfused with 4% paraformaldehyde, and brain tissue containing the hypothalamus was collected, sectioned, and processed for detection of mRNA (RNAscope) and protein (immunohistochemistry) for kisspeptin and NKB. Mean LH was significantly lower and LH inter-pulse interval was significantly higher in FR wethers compared to FM wethers at the end of the experiment (Week 13). RNAscope analysis revealed significantly fewer cells expressing mRNA for kisspeptin and NKB in FR wethers compared to FM controls, and immunohistochemical analysis revealed significantly fewer immunopositive kisspeptin and NKB cells in FR wethers compared to FM wethers. Taken together, this data supports the idea that long-term feed restriction regulates GnRH/LH secretion through central suppression of kisspeptin and NKB in male sheep. Lay summary While undernutrition is known to impair reproduction at the level of the brain, the components responsible for this in the brain remain to be fully understood. Using male sheep we examined the effect of undernutrition on two stimulatory molecules in the brain critical for reproduction: kisspeptin and neurokinin B. Feed restriction for several weeks resulted in decreased luteinizing hormone in the blood indicating reproductive function was suppressed. In addition, undernutrition also reduced both kisspeptin and neurokinin B levels within a region of the brain involved in reproduction, the hypothalamus. Given that they have stimulatory roles in reproduction, we believe that undernutrition acts in the brain to reduce kisspeptin and neurokinin B levels leading to the reduction in luteinizing hormone secretion. In summary, long-term undernutrition inhibits reproductive function in sheep through suppression of kisspeptin and neurokinin B within the brain.

Demographic changes are causing a rapid increase in the number of people over 65 years of age. This is associated with an increase in the number of multimorbid patients in need of care. Nationally as well as internationally, there is little information on the treatment of psoriasis patients in the nursing home setting and on the question of how this is influenced by entry into a nursing home.The aim was to discuss the results of previous routine data analyses on the treatment of psoriasis patients in nursing homes with medical providers (dermatologists, general practitioners, nursing service managers, and nursing staff) on the basis of interviews and focus groups, to identify difficulties in the treatment and finally to derive recommendations for action regarding sustainable gerontodermatological treatment.Qualitative guideline-based interviews and focus groups with dermatologists (n = 5), general practitioners (GPs, n = 7), nurses (n = 7), and care managers (n = 2) were conducted. The data were evaluated by content analysis.The analyses resulted in 344 statements, which could be categorized into 14 main topics. The results show that there is a need for improvement in the quality of care for people with skin diseases, especially psoriasis, in nursing homes. This is evident at both the medical and nursing levels. According to the providers (N = 21), this can be addressed in particular through increased remote consultations (telemedicine), dermatological training for GPs and nurses, and closer cooperation between the individual disciplines.Remote consultations, but also a specific guideline on the "skin of the ageing person" can be useful to improve the dermatological care situation in nursing homes and thus increase the well-being of those affected.HINTERGRUND: Demografische Veränderungen bewirken einen steilen Anstieg der Anzahl der über 65-Jährigen. Damit verbunden ist die Zunahme der Anzahl pflegebedürftiger, multimorbid Erkrankter. National wie auch international gibt es keine Informationen insbesondere zur Versorgung von Psoriasiserkrankten im Setting Pflegeheim und zur Frage, wie diese durch den Eintritt in ein Pflegeheim beeinflusst wird.Ziel war es, anhand von Interviews bzw. Fokusgruppen die Ergebnisse vorausgehender Routinedatenanalysen zur Versorgung Psoriasiserkrankter in Pflegeheimen mit medizinischen Versorgern (Dermatologen, Allgemeinmediziner, Pflegedienstleitungen und Pflegekräfte) zu diskutieren, Schwierigkeiten der Versorgung aufzudecken und abschließend Handlungsempfehlungen für eine zukunftsfähige gerontodermatologische Versorgung abzuleiten.Durchgeführt wurden qualitative Leitfaden-gestützte Interviews und Fokusgruppen mit Dermatologen (n = 5), Allgemeinmedizinern (n = 7), Pflegekräften (n = 7) und Pflegedienstleitungen (n = 2). Die Daten wurden inhaltsanalytisch ausgewertet.Die Auswertung ergab insgesamt 344 Aussagen, die insgesamt 14 Hauptkategorien zugeordnet werden konnten. Die Ergebnisse zeigen, dass für die Versorgungsqualität von Menschen mit Hautkrankheiten, insbesondere Psoriasis, in Pflegeinrichtungen ein Verbesserungsbedarf besteht. Dieser zeigt sich sowohl auf ärztlicher als auch auf pflegerischer Ebene. Laut der Versorger (N = 21) kann dies insbesondere durch eine verstärkte digitale Versorgung, dermatologische Schulungen für Hausärzte und Pflegefachkräfte sowie engere Kooperationen zwischen den einzelnen Disziplinen adressiert werden.Digitale Pflegekonsile, aber auch eine spezifische Leitlinie zur „Haut des alternden Menschen“ können von Nutzen sein, um die dermatologische Versorgungssituation im Pflegeheim zu verbessern und somit das Wohlbefinden der Betroffenen zu steigern.

Undernutrition limits reproduction through inhibition of gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH) secretion. Because KNDy neurons coexpress neuropeptides that play stimulatory (kisspeptin and neurokinin B [NKB]) and inhibitory (dynorphin) roles in pulsatile GnRH/LH release, we hypothesized that undernutrition would inhibit kisspeptin and NKB expression at the same time as increasing dynorphin expression. Fifteen ovariectomized lambs were either fed to maintain pre-study body weight (controls) or feed-restricted to lose 20% of pre-study body weight (FR) over 13 weeks. Blood samples were collected and plasma from weeks 0 and 13 were assessed for LH by radioimmunoassay. At week 13, animals were killed, and brain tissue was processed for assessment of KNDy peptide mRNA or protein expression. Mean LH and LH pulse amplitude were lower in FR lambs compared to controls. We observed lower mRNA abundance for kisspeptin within KNDy neurons of FR lambs compared to controls with no significant change in mRNA for NKB or dynorphin. We also observed that FR lambs had fewer numbers of arcuate nucleus kisspeptin and NKB perikarya compared to controls. These findings support the idea that KNDy neurons are important for regulating reproduction during undernutrition in female sheep.

Objective The aim of this study was to map the phases and individual steps of the cooperative planning process, a specific participatory approach frequently used in German sports and physical activity promotion, and to explore facilitators, barriers, and challenges experienced by those leading its implementation in selected projects. Background More than half of the global population is not physically active enough. Therefore, the demand for more effective physical activity programs is growing. Participatory-based interventions, using the cooperative planning process, offer the potential to plan new programs that match population group and setting characteristics. This approach was extensively applied in German sports and physical activity fields, serving as a mechanism to develop and implement specific measures to change the population’s behaviour. We analysed four German empirical projects promoting sports and physical activity to identify how the approach was adapted to each project, which phases were considered, and which key performance indicators enhanced (facilitators), exacerbated (barriers), or challenged the process. Methods This study used a mixed-methods approach, including a systematic analysis of documents (n = 10) and in-depth, semi-structured interviews (n = 4) with the empirical projects’ scientific members. Results The cooperative planning process was shaped across its phases by several facilitators, challenges, and barriers. Diverse assessment procedures and recruitment tools can facilitate preparation of the process, while moderation requires particular attention during the development phase. Identifying a champion in the transition subphase and providing ongoing scientific counselling can assure the implementation of an action plan with tailored measures for sports and physical activity promotion. Conclusions This study contributes to a better understanding of the complexity of the cooperative planning approach and, therefore, flexibility in sports and physical activity promotion projects. Many preparation actions, several challenges in the planning process, and a critical transition in implementation responsibilities should be considered by future projects intending to adopt the approach.

The enterprise of conservation is inherently ethical, requiring conservationists to navigate morally challenging problems. Working together, conservationists and ethicists have developed the field of conservation ethics. Yet, due to the deeply interdisciplinary nature of the field, conservation ethics faces a unique set of challenges. We first comment on the harm caused by reciprocal ignorance between some practicing conservationists and ethicists. We then explore the difficulties of creating a widely applied ethic, examining conversations surrounding the recently emerged virtue ethic, Compassionate Conservation. By bringing attention to these challenges, and highlighting medical bioethics as a touchstone of productive applied ethical theory, we can help the field avoid unproductive pitfalls, as well as facilitate positive and productive communication and collaboration between the various members of the different disciplines involved.

Puberty onset is a complex physiological process, which enables the capacity for reproduction through increased gonadotropin-releasing hormone and subsequently luteinizing hormone secretion. While cells that coexpress kisspeptin, neurokinin B (NKB), and dynorphin in the hypothalamic arcuate nucleus are believed to govern the timing of puberty, the degree to which kisspeptin/NKB/dynorphin (KNDy) neurons exist and are regulated by pubertal status remains to be determined in the gilt. Hypothalamic tissue from prepubertal and postpubertal, early follicular phase gilts was used to determine the expression of kisspeptin, NKB, and dynorphin within the arcuate nucleus. Fluorescent in situ hybridization revealed that the majority (>74%) of arcuate nucleus neurons that express mRNA for kisspeptin coexpressed mRNA for NKB and dynorphin. There were fewer arcuate nucleus cells that expressed mRNA for dynorphin in postpubertal gilts compared to prepubertal gilts (P

Introduction In health care, teamwork is the foundation for efficient processes and effective outcomes and serves as a cornerstone of quality care. Good teamwork often requires training and practice. The primary aims of this study were to assess the impact of psychosocial simulations on participant knowledge of other professionals’ responsibilities and capabilities and on confidence and competence of psychosocial team members in collaborating and communicating with other psychosocial team members. Secondarily, we assessed participant satisfaction. Methods This single-site study used a pre- and post-survey design of social workers, chaplains, and child life specialists who attended a psychosocial simulation education module. Participants took the Psychosocial Simulation Participant Survey (PSPS), a 19-question survey tool developed by the research team. Pre- and post-simulation responses were summarized and compared using standard statistical analysis methods. Results Participants showed significant improvement in the subscales of Learning and Performance, Benefits of Training, and Cooperation. Two of the three Communication subscale questions showed significant improvements. Previous and current role as participant or observer, past experience with simulation, gender, discipline, age, years at institution, and area of regular assignment were not related to improvement in any of the outcomes. Over 90% of the participants agreed or strongly agreed with the statement “I was satisfied with my simulation experience” and “The post scenario discussion (debriefing) helped me to understand, reflect, and think critically.“ Conclusions The use of simulation training with psychosocial professionals is an effective means of teaching new competencies and of promoting interprofessional collaboration.

Previous studies showed that the small leftward bias found in healthy humans’ spatial judgments of lines (“pseudoneglect”) shifts to the right with increasing distance between stimuli and observer. In this study, we investigated whether such a modulation of attentional asymmetry can also be observed in free visual exploration. Participants freely explored photographs of naturalistic scenes for 7 s in near (60 cm) and far (140 cm) space. After an initial leftward bias, followed by a compensatory rightward bias, gaze positions were significantly more leftward in near compared to far space (around 4 s from scene onset). Our results show that the modulation of attentional asymmetries by viewing distance previously reported for spatial judgments generalizes to free visual exploration, and we revealed the temporal dynamics of these asymmetries by fine-grained eye movement analysis. In contrast, an effect of viewing distance was reduced or absent when eye movements are under strong top-down control, as in systematic serial visual search (Sensitive Negelct Test). Finally, there was no effect of viewing distance in the landmark task (as also reported in a minority of other studies), suggesting that this effect may depend on specific, yet unidentified task characteristics.

The human brain encodes information in neural activation patterns. While standard approaches to analyzing neural data focus on brain (de-)activation (e.g., regarding the location, timing, or magnitude of neural responses), multivariate neural pattern similarity analyses target the informational content represented by neural activity. In adults, a number of representational properties have been identified that are linked to cognitive performance, in particular the stability, distinctiveness, and specificity of neural patterns. However, although growing cognitive abilities across childhood suggest advancements in representational quality, developmental studies still rarely utilize information-based pattern similarity approaches, especially in electroencephalography (EEG) research. Here, we provide a comprehensive methodological introduction and step-by-step tutorial for pattern similarity analysis of spectral (frequency-resolved) EEG data including a publicly available pipeline and sample dataset with data from children and adults. We discuss computation of single-subject pattern similarities and their statistical comparison at the within-person to the between-group level as well as the illustration and interpretation of the results. This tutorial targets both novice and more experienced EEG researchers and aims to facilitate the usage of spectral pattern similarity analyses, making these methodologies more readily accessible for (developmental) cognitive neuroscientists.

Advancing gilt puberty onset is financially desirable for swine production. Neurons in the hypothalamic arcuate nucleus (ARC) that co-express kisspeptin, neurokinin B (NKB), and dynorphin (i.e. KNDy cells) are believed to control gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) secretion, but their role in gilt pubertal development is unknown. We hypothesized that puberty onset in gilts would coincide with greater expression of mRNA for kisspeptin and NKB, and less expression of dynorphin. Using fluorescent in situ hybridization (RNAscope), we examined expression of kisspeptin, NKB, and dynorphin in pre- and postpubertal gilts from two genetic lines divergently selected for age at puberty. Prepubertal (n = 6/line) and postpubertal (n = 6/line) gilts were used, and postpubertal animals all received Matrix (0.22% altrenogest) orally for 14 days with tissue collection two days after the final dose. Gilts were euthanized and heads were perfused with 8 L of 4% paraformaldehyde (PFA). Hypothalamic brain tissue was removed, placed in 4% PFA for 24 hrs, and then in 20% sucrose until sectioning (50 µm). Sectioned tissue was stored in cryopreservative at -20°C until RNAscope. Data were analyzed using SAS software (Version 9.4, SAS Institute, Cary NC) with significance declared at P < 0.05. We determined mRNA expression for kisspeptin was not different between groups (P > 0.05). In addition, we found that mRNA expression for NKB was higher in prepubertal gilts compared to postpubertal gilts (P < 0.05) but was not different between lines; mRNA expression was lowest in postpubertal late puberty gilts. Furthermore, total number of dynorphin cells were higher in prepubertal gilts compared to postpubertal gilts (P < 0.05), while individual cell mRNA expression for dynorphin was greatest in postpubertal early puberty gilts (P < 0.05). Taken together, we suggest puberty onset in gilts is more dependent on NKB and dynorphin than kisspeptin.

Maintaining serial order in working memory is crucial for cognition. Recent theories propose that serial information is achieved by positional coding of items on a spatial frame of reference. In line with this, an early-left and late-right spatial-positional association of response code (SPoARC) effect has been established. Various theoretical accounts have been put forward to explain the SPoARC effect (the mental whiteboard hypothesis, conceptual metaphor theory, polarity correspondence, or the indirect spatial-numerical association effect). Crucially, while all these accounts predict a left-to-right orientation of the SPoARC effect, they make different predictions regarding the direction of a possible vertical SPoARC effect. In this study, we therefore investigated SPoARC effects along the horizontal and vertical spatial dimension by means of saccadic responses. We replicated the left-to-right horizontal SPoARC effect and established for the first time an up-to-down vertical SPoARC effect. The direction of the vertical SPoARC effect was in contrast to that predicted by metaphor theory, polarity correspondence, or by the indirect spatial-numerical association effect. Rather, our results support the mental whiteboard-hypothesis, according to which positions can be flexibly coded on an internal space depending on the task demands. We also found that the strengths of the horizontal and vertical SPoARC effects were correlated, showing that some people are more prone than others to use spatial references for position coding. Our results therefore suggest that context templates used for position marking are not necessarily spatial in nature but depend on individual strategy preferences.

Puberty onset in gilts is an awakening of the hypothalamic-pituitary-ovarian axis that is the result of reduced estradiol-negative feedback at the level of the hypothalamus which yields elevated gonadotropin secretion from the anterior pituitary. Given the importance of hypothalamic kisspeptin and neurokinin B (NKB) signaling for the onset of puberty in other species, the objective of this study was to determine if gilts selected for early pubertal onset (SELECT) would display measurable differences within the hypothalamus (i.e. increased expression of kisspeptin and NKB) and within the ovary (i.e. increased ovarian mass) compared to age-matched and weight-matched gilts (CONTROL) that achieve puberty 20 days later than SELECT gilts. Gilts were sacrificed at three timepoints: Timepoint A, both groups were determined to be prepubertal (n=6/group), Timepoint B, SELECT gilts were determined to be pubertal and CONTROL gilts were determined to be prepubertal (n=6/group), and Timepoint C, both groups were determined to be pubertal (n=6/group). All animals were euthanized, heads were perfused with 8 L of 4% paraformaldehyde, and ovaries were harvested. Brain tissue was removed post-fixation, submerged in fixative for 24 hrs followed by 20% sucrose until sectioned for immunohistochemistry. Ovarian mass tended (p≤0.10) to be greater for SELECT gilts on the right ovary (4.34 vs. 3.67 g) and the left ovary (4.49 vs. 3.68 g) when compared to CONTROL (Timepoints A and C), and at Timepoint B right ovary mass from SELECT gilts was heavier than CONTROL gilts (p< 0.05; 7.22 vs. 4.65 g). Hypothalamic immunohistochemistry for kisspeptin and NKB revealed differences in neuronal fiber density between both groups at various timepoints. Therefore, we conclude that gilts genetically selected for early puberty do so via changes within the hypothalamus that increase gonadotropin secretion and, in turn, stimulate ovarian growth to ultimately advance the timing of puberty onset.

Graphical abstract, Highlights • We show repetition effects in event-related potentials across children and adults. • Repetition effects were related to specific item (but not mere category) memory. • Association of repetition effects and memory did not differ between age groups. • We demonstrate an age-independent neural indicator of high-fidelity memory encoding., The specificity with which past experiences can be remembered varies across the lifespan, possibly due to differences in how precisely information is encoded. Memory formation can be investigated through repetition effects, the common finding that neural activity is altered when stimuli are repeated. However, whether differences in this indirect measure of memory formation relate to lifespan differences in memory specificity has not yet been established. In the present study, we examined repetition effects in event-related potentials and their relation to recognition. During incidental encoding, children (aged 7–9 years), young adults (18–30 years), and older adults (65–76 years) viewed repeated object images from different categories. During subsequent recognition, we distinguished memory for the specific items versus the general categories. We identified repetition suppression in all age groups, and repetition enhancement for adults. Furthermore, individual item recognition performance comprising lure discrimination was positively associated with the magnitude of the neural repetition effects, which did not differ between groups, indicating common neural mechanisms of memory formation. Our findings demonstrate that neural repetition effects reflect the formation of highly specific memory representations and highlight their significance as a neural indicator of individual differences in episodic memory encoding across the lifespan.

The distinctiveness of neural information representation is crucial for successful memory performance but declines with advancing age. Computational models implicate age-related neural dedifferentiation on the level of item representations, but previous studies mostly focused on age differences of categorical information representation in higher-order visual regions. In an age-comparative fMRI study, we combined univariate analyses and whole-brain searchlight pattern similarity analyses to elucidate age differences in neural distinctiveness at both category and item levels and their relation to memory. Thirty-five younger (18-27 years old) and 32 older (67-75 years old) women and men incidentally encoded images of faces and houses, followed by an old/new recognition memory task. During encoding, age-related neural dedifferentiation was shown as reduced category-selective processing in ventral visual cortex and impoverished item specificity in occipital regions. Importantly, successful subsequent memory performance built on high item stability, that is, high representational similarity between initial and repeated presentation of an item, which was greater in younger than older adults. Overall, we found that differences in representational distinctiveness coexist across representational levels and contribute to interindividual and intraindividual variability in memory success, with item specificity being the strongest contributor. Our results close an important gap in the literature, showing that older adults' neural representation of item-specific information in addition to categorical information is reduced compared with younger adults.SIGNIFICANCE STATEMENTA long-standing hypothesis links age-related cognitive decline to a loss of neural specificity. While previous evidence supports the notion of age-related neural dedifferentiation of category-level information in ventral visual cortex, whether or not age differences exist at the item level was a matter of debate. Here, we observed age group differences at both levels as well as associations between both categorical distinctiveness and item specificity to memory performance, with item specificity being the strongest contributor. Importantly, age differences in occipital item specificity were largely due to reduced item stability across repetitions in older adults. Our results suggest that age differences in neural representations can be observed across the entire cortical hierarchy and are not limited to category-level information.

Proper energy balance is important to ensure reproductive success. Chronic nutrient restriction is known to suppress hypothalamic-pituitary function, but the central mechanisms whereby undernutrition inhibits GnRH/LH secretion remain largely unknown. KNDy neurons, which co-express kisspeptin, neurokinin B (NKB), and dynorphin, form a unique population of cells in the arcuate nucleus (ARC) of the hypothalamus and play a critical role in GnRH/LH pulse generation. Based on recent evidence from our lab that chronic feed restriction reduces kisspeptin and NKB protein expression in young male sheep, we hypothesized that nutrient restriction would inhibit mRNA abundance for kisspeptin and NKB in the same animals. Fourteen wethers were placed into a fed to maintain body weight group (n=6; Fed) or a feed-restricted to lose 15-20% of pre-study body weight group (FR; n=8). Weekly blood samples (every 12 minutes for 4.5 hours) were taken via jugular venipuncture and plasma was stored at -20°C until the time of radioimmunoassay. Weekly body weights were recorded and feed amounts were adjusted to achieve desired body weights. At Week 13, animals were euthanized following blood collection, brain tissue was perfused with 4% paraformaldehyde, and tissue containing the hypothalamus was collected. Following submersion in 20% sucrose for at least four weeks, hypothalamic blocks were sectioned at 50 µm on a freezing microtome, and stored in a cryopreservative solution until processing. At Week 13, the average percent change in body weight was clearly evident (Fed, 6.79 + 3.4% vs FR, -19.82 ± 1.6%), and mean LH was significantly lower in FR wethers (13.41 + 3.7 ng/ml) compared to Fed controls (26.43 + 2.5 ng/ml). To assess changes in mRNA abundance, we used a relatively new in situ hybridization technique, RNAscope, to quantify mRNA for kisspeptin and NKB in the ARC with probes that were ovine-specific. Results showed that feed restriction reduced the number of kisspeptin mRNA-expressing cells (Fed, 231.2 + 14.4 vs FR, 100.3 + 35.9) and NKB mRNA-expressing cells (Fed, 192.7 + 18.4 vs FR, 97.3 + 21.7) per hemi-section. Furthermore, analysis of kisspeptin and NKB co-expressing cells (30 cells/animal) revealed that feed restriction significantly reduced the average mRNA integrated density for NKB, but not kisspeptin, compared to Fed controls. Together, these findings further support a role for kisspeptin and NKB in the central mechanism governing GnRH/LH secretion during undernutrition in male sheep.

We present four datasets that provide information on primary production, nitrogen (N) uptake and allocation in two salt marsh grasses, short-form Spartina alterniflora and Distichlis spicata. These four datasets were generated during a month-long stable isotope (15N) tracer study described in the companion manuscript (Hill et al., 2018). They include an allometry dataset containing mass and height data for individual plants harvested from Colt State Park, Bristol, Rhode Island and used to nondestructively estimate plant masses. A second dataset contains weekly stem height measurements collected over the course of the 15N tracer study. Also included are high resolution data from 49 vegetated compartments (leaves, stems, fine/coarse roots, rhizomes) and bulk sediment depth intervals, reporting the mass, carbon and N concentrations, and stable isotope ratios measured following the harvest of cores over time. Additionally, we provide a complementary dataset with estimates of microbial removal from potential and ambient denitrification enzyme assays. These data, along with source code used in their analysis, are compiled in the NitrogenUptake2016 R package available from the Comprehensive R Archive Network.

Salt marshes have the potential to intercept nitrogen that could otherwise impact coastal water quality. Salt marsh plants play a central role in nutrient interception by retaining N in above- and belowground tissues. We examine N uptake and allocation in two dominant salt marsh plants, short-form Spartina alterniflora and Distichlis spicata. Nitrogen uptake was measured using 15N tracer experiments conducted over a four-week period, supplemented with stem-level growth rates, primary production, and microbial denitrification assays. By varying experiment duration, we identify the importance of a rarely-measured aspect of experimental design in 15N tracer studies. Experiment duration had a greater impact on quantitative N uptake estimates than primary production or stem-level relative growth rates. Rapid initial scavenging of added 15N caused apparent nitrogen uptake rates to decline by a factor of two as experiment duration increased from one week to one month, although each experiment shared the qualitative conclusion that Distichlis roots scavenged N approximately twice as rapidly as Spartina. We estimate total N uptake into above- and belowground tissues as 154 and 277 mg N·m-2·d-1 for Spartina and Distichlis, respectively. Driving this pattern were higher N content in Distichlis leaves and belowground tissue and strong differences in primary production; Spartina and Distichlis produced 8.8 and 14.7 g biomass·m-2·d-1. Denitrification potentials were similar in sediment associated with both species, but the strong species-specific difference in N uptake suggests that Distichlis-dominated marshes are likely to intercept more N from coastal waters than are short-form Spartina marshes. The data and source code for this manuscript are available as an R package from https://github.com/troyhill/NitrogenUptake2016.

Classic bottom-up theory predicts that increased resource availability (for example, nutrients) at the base of the food web will stimulate primary production and, in turn, secondary production. Recent studies, however, indicate that bottom-up controls on food web production can be modified by other factors, such as landscape configuration and continuity. As part of a 10-year ecosystem-scale experiment in a New England salt marsh, we investigated the response of secondary consumers, specifically a fish, the mummichog (Fundulus heteroclitus), to nutrient enrichment. In the first 6 years, we observed a classic bottom-up response of increased production of algae, invertebrate prey, and mummichogs. After the sixth year, however, mummichog biomass declined to below reference levels by the eighth year. This decline in mummichog biomass coincided with nutrient-induced collapse of the low-marsh habitat. Based on stable isotope analyses, field surveys, and small-scale experiments, we suggest that the geomorphic changes induced a trophic decoupling between creek and marsh habitats, thereby reducing mummichog access to prey in the intermittently flooded marsh. Thus, despite continued stimulation of algal and invertebrate prey production, fish abundances declined to below pre-enrichment levels. Our results demonstrate how geomorphic controls can override classic bottom-up control and emphasize the importance of long-term studies in detecting the response of slow-turnover phenomena (for example, changing landscapes).

Expression of HMGA2 is strongly associated with body size and growth in mice and humans. In mice, inactivation of one or both alleles of Hmga2 results in body-size reductions of 20% and 60%, respectively. In humans, microdeletions involving the HMGA2 locus result in short stature, suggesting the function of the HMGA2 protein is conserved among mammals. To test this hypothesis, we generated HMGA2-deficient pigs via gene editing and somatic cell nuclear transfer (SCNT). Examination of growth parameters revealed that HMGA2-/+ male and female pigs were on average 20% lighter and smaller than HMGA2+/+ matched controls (P < 0.05). HMGA2-/- boars showed significant size reduction ranging from 35 to 85% of controls depending on age (P < 0.05), and organ weights were also affected (P < 0.05). HMGA2-/+ gilts and boars exhibited normal reproductive development and fertility, while HMGA2-/- boars were sterile due to undescended testes (cryptorchidism). Crossbreeding HMGA2-/+ boars and gilts produced litters lacking the HMGA2-/- genotype. However, analysis of day (D) D40 and D78 pregnancies indicated that HMGA2-/- fetuses were present at the expected Mendelian ratio, but placental abnormalities were seen in the D78 HMGA2-/- concepti. Additionally, HMGA2-/- embryos generated by gene editing and SCNT produced multiple pregnancies and viable offspring, indicating that lack of HMGA2 is not lethal per se. Overall, our results show that the effect of HMGA2 with respect to growth regulation is highly conserved among mammals and opens up the possibility of regulating body and organ size in a variety of mammalian species including food and companion animals.