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The diagnosis of central nervous system tumours has been transformed in recent years from a microscopic morphology-based process to one dominated by the identification of somatic genetic alterations in tumour cells. This switch requires implementing radically different methods, for which appropriate training and financial resources must be allocated. The Canadian Association of Neuropathologists (CANP) has followed a process based on the scientific literature and consensus to develop recommendations for molecular testing of tumours of the brain and spinal cord, aiming to balance the need for treatment-determinant accurate diagnosis and the current limitations inherent in the transition to a new paradigm. The Professional Affairs Committee was charged with this task. A draft was discussed during the CANP general assembly, along with presentations from groups who had implemented molecular technologies, as well as others who relied on external laboratories. The Professional Affairs Committee summarised the consensus and submitted their recommendation to the CANP’s Executive Committee. A final report was posted on the CANP website for a month to allow all members to comment. The recommendations below apply to intrinsic tumours of the central nervous system and do not include metastatic disease or tumours impinging upon the nervous system from outside. These recommendations should be considered clinically relevant, as the results have direct consequences on the patient’s treatment, either through the use of targeted therapies or the trial-proven best application of radiation and/or chemotherapy.
Empathy is an essential skill in the doctor-patient relationship since it contributes to improve aspects of health care and patient satisfaction. Nevertheless, burnout research projects have been developed in recent years.
Objectives
To examine the predictive capacity that empathy has on burnout syndrome in health professionals.
Methods
A non-experimental, cross-sectional design was proposed. The type of study was correlational-descriptive since it was sought out to explore a functional relation through the prognosis of a criterion variable. Sample: 200 (100 female and 100 male).
Results
First, the variance of cognitive and Affective Empathy was dug out in the emotional exhaustation criterion scale. Results accounted for 15% of variability in emotional exhaustation. (Corrected R 2 = .15, F = 17,56, p = 0,00). The best predictor of emotional exhaustation refers to Cognitive Empathy. (B = -.27, p = 0.00). It does not seem that Affective Empathy acts as a predictor variable of Emotional Exhaustation. (Table 1).Table 1
Multiple linear regression analysis considering Emotional Exhaustation as a criterion.
TECA
Corrected R2
F
B
p
Cognitive Empathy
.15
17,5
-.27**
0,00
Affective Empathy
-.14
.13
The predictive capacity of Empathy in relation to Depersonalization was estimated (Corrected R 2 = .20, F = 25,4, p = 0.00). Cognitive and affective empathy were included as predictor variables and MBI as a criterion variable (Table 2). On one hand, the best predictor of Depersonalization is the Cognitive Empathy. On the other hand, regarding Affective Empathy, it does not act as a predictor of Depersonalization.Table 2
Multiple linear regression analysis considering Depersonalization as a criterion.
TECA
Corrected R2
F
B
p
Cognitive Empathy
.20
25,4
-.32**
0,00
Affective Empathy
-.15
.84
Lastly, the predictive capacity of Empathy in relation to Personal Achievement was figured out. (Corrected R 2 = .19, F = 23,4, p = 0.00). Cognitive Empathy is the best predictor for Personal Fulfillment (Table 3).Table 3
Multiple linear regression analysis considering Personal Fullfilment as a criterion.
TECA
Corrected R2
F
β
p
Cognitive Empathy
.20
25,4
.43**
0,00
Affective Empathy
.00
.96
Conclusions
It was noticed that through a linear multiple regression analysis, the variable that best explains Emotional Exhaustation is Cognitive Empathy. Those results are replicated for Depersonalization and Personal Fullfilment.
According to Bisquerra Alzina (2003),competencies are defined as a set of knowledge, capabilities, skills and attitudes, necessary to understand, express and regulate emotional phenomena appropriately and which are fundamental in the teaching profesion since they are closely related to students´performance and mental health.
Objectives
compare socio-emotional skills in two groups of participants: female and male
Methods
A non-experimental,cross-sectional design was proposed for this study. The scope of this research is descriptive, in the sense,that it seeks to establish measures in regard to specific variables. Sample (100 female and 100 male).
Results
Results revealed that the evaluated teachers show average level of socio-emotional competencies, (Table 1).The highest scores were encountered in relation to the optimism competence. It suggests that teachers have the ability to obtain favorable balances from adverse situations presented in their daily lives.Table 1:
Distribution of socio-emotional competency levels in the professionals evaluated
LOW %
MEDIUM %
HIGHT %
EMOTIONAL AWARENESS
19
80
1
SELF EFFICACY
32
66
2
EMOTIONAL REGULATION
17
81
2
EMOTIONAL EXPRESSION
6
85
9
PROSOCIALITY
6
85
9
ASSERTIVENESS
6
82
12
OPTIMISM
0
21
79
EMOTIONAL AUTONOMY
25
71
4
EMPATHY
8
85
7
Findings showed that there exists a statiscally significative difference (P=0,000) in the empathy and self-efficacy dimensions. Women obtained higher scores in these two abilities in regard to men. (Table 2). No differences were observed in the rest of the competences evaluated.Table 2:
Differences according to men and women
FEMALE
MALE
SELF EFFICACY
1,78
1,61
EMPATHY
2,02
1,96
Conclusions
Although teachers´s socio-emotional competences were classified in medium levels, it is necessary to implement an intervention design that allows to streghten those dimensions since they could improve not only the relationships with their students but also teachers´ mental health.
The Dunning-Krueger effect is a cognitive bias where individuals tend to overestimate their abilities in areas where they are less competent. The Cordoba Naming Test (CNT) is a 30-item confrontation naming task. Hardy and Wright (2018) conditionally validated a measure of perceived mental workload called the NASA Task Load Index (NASA-TLX). Researchers reported that workload ratings on the NASA-TLX increased with increased task demands on a cognitive task. Anxiety is known as an emotion that can make an individual more susceptible to develop a mental health condition. We examine if the Dunning-Krueger effect occurs in a Mexican population with and without current symptoms of anxiety and possible factors driving individuals to overestimate their abilities on the CNT. We predicted the abnormal symptoms of anxiety (ASA) group would report better CNT performance, report higher perceived workloads on the CNT, and underperform on the CNT compared to the normal symptoms of anxiety (NSA) group. We also predicted the low-performance group would report better CNT performance, report higher perceived workloads on the CNT, and underperform on the CNT compared to the high-performance group.
Participants and Methods:
The sample consisted of 192 Mexican participants with NSA (79 low-performance & 113 high-performance) and 74 Mexican participants with ASA (44 low-performance & 30 high-performance). Participants completed the CNT, NASA-TLX, and the Hospital Anxiety and Depression Scale (HADS) in Spanish. The NASA-TLX was used to evaluate perceived workloads after the completion of the CNT. Meanwhile, the HADS was used to create our anxiety groups. Finally, CNT raw scores were converted into T-scores, which then were averaged to create the following two groups: low-performance (CNT T-Score <50) and high-performance (CNT T-Score 50+). A series of 2x2 ANCOVAs, controlling for gender were used to evaluate CNT performance and perceived workloads.
Results:
We found a significant interaction where the low-performance ASA and the high-performance NSA groups demonstrated better CNT performance and reported higher perceived workloads (i.e., performance, temporal demand) on the CNT compared to their respective counterparts (i.e., low-performance NSA & high-performance ASA groups), p's<.05, ηp's2=.02. We found a main effect where the high-performance group outperformed the low-performance group on the CNT and reported lower perceived workloads on the CNT, p's<.05, ηp's2 =.04-.46.
Conclusions:
The Dunning-Krueger effect did not occur in our sample. Participants that demonstrated better CNT performance also reported higher perceived workloads regardless of their current symptoms of anxiety. A possible explanation can be our sample's cultural norms of what would be considered as abnormal symptoms of anxiety, is a normal part of life, decreasing the possibilities to experience self-efficacy distoritions. Future studies should investigate whether the Dunning-Kruger effect may be influencing other aspects of cognitive functioning subjectively in Mexicans residing in Mexico and the United States with and without current symptoms of anxiety.
Early intervention on a first psychotic episode is fundamental for a more favorable prognosis, and it usually combines pharmacological treatment, which mainly affects positive psychotic symptoms, with interventions that can improve the rest of the symptoms and associated problems such as deterioration in social functioning (Harvey & Penn, 2010; Fusar-Poli, McGorry & Kane, 2017). While Mindfulness is gaining more and more prominence in the field of psychotherapy (Chan et al., 2019; Cillesen et al., 2019), social cognition and social functioning are being researched as key targets on which to intervene after a first psychotic episode (Green, Horan & Lee, 2015).
SocialMIND® is a mindfulness-based social cognition training tailor-made to improve social functioning in people who have suffered a first psychotic episode within the last five years. It is currently being compared with a group Psychoeducational Multicomponent Intervention (PMI) in a Randomized Controlled Trial (RCT) (Mediavilla et al., 2019). Both group psychotherapies include 17 sessions delivered over a 9 month period: 8 weekly sessions, 4 biweekly sessions and 5 monthly sessions.
The results of SocialMIND® at 8 weeks showed improvements in social cognition and social functioning, specifically on affective social cognition and self-care (Mediavilla et al., 2021).
Objectives
To evaluate the efficacy of SocialMIND® in improving social functioning, measured by the Personal and Social Functioning (PSP) scale 16 weeks after starting the intervention, in people who have suffered a first psychotic episode in the last 5 years.
Methods
Randomized, controlled pilot trial (use of a psychoeducational multicomponent intervention or PMI as active comparator) of two parallel groups (SocialMIND® and PMI) with a 1:1 ratio using a blind evaluator.
Results
No statistically significant differences were found in the social functioning variable between the two treatment arms. Intragroup differences are observed in other secondary variables studied (social cognition) 16 weeks after starting the interventions.
Conclusions
SocialMIND® has not been shown to be more effective than a PMI in improving social functioning at 16 weeks after starting the intervention in people who have suffered a first psychotic episode in the five years prior to being included in the study.
Almost nine months after the start of the war between Russia and Ukraine, millions of people have been affected physically, economically and mainly mentally. Those who have stayed in their homeland, and the ones that have chosen to emigrate to a safer place.
Objectives
The objective of this article is to assess the importance of social stressors in the onset of a brief psychotic episode, even in the absence of substance abuse or previous illnesses.
Methods
The case of a 45-year-old woman is described, known by the Pediatric Emergency Service, for being the tutor of a patient who suffered from anxiety attacks, having emigrated without her parents from Ukraine together with her 5 brothers. The psychotic episode begins when our patient gets notified that she must abandon the custody of the girl, because she will have to go to Turkey with her legal guardians. The family explains the behavioral changes that the patient made and how the clinical picture worsened.
Results
She was admitted at the Hospital’s Psychiatry Service and antipsychotics treatment started. After 5 days, the episode had completely been solved.
Conclusions
In conclusion, we highlight the importance of social problems in the development of a psychiatric pathology and the necessary elements to prevent it: family support network, fast and efficient care services and availability of hospital and pharmaceutical resources.
Steroids are a necessary treatment for hypoxic respiratory failure; however there are many side effects that should be taken into account. A 44- year-old-woman with asthma and no past psychiatric history was admitted due to COVID-19 pneumonia and Respiratory syncytial virus (RSV) infection, presenting hypoxic respiratory failure. After two days of intravenous methylprednisolone administration, the patient presented acute psychosis and agitation.
It has been previously described that steroid use can cause effects such as mania, anxiety, agitation, delirium and psychosis amongst other. However they are a necessary treatment in respiratory illnesses and are sometimes unavoidable.
Objectives
The aim was to examine the appropriate medical response to steroid induced psychosis in patients with acute hypoxic failure.
Methods
A bibliographical review was done in PubMed database searching recent cases of steroid induced psychosis using the words (“Steroid”, “Psychosis” and “COVID-19”).
Results
According to literature, it has been shown that partial or complete reduction of steroid use and/or use of psychotropic has been successfully used to treat steroid induced psychosis. Following the research it was decided to reduce intravenous methylprednisolone dose from 20mg/ 8h to 20mg/12h and start oral haloperidol 5mg/8h the first 24h and reducing the dose progressively as the patient recovered. After the first 24 hours the patient presented adequate response to steroids as well as partial response to antipsychotic treatment; presenting no further agitation, absence of hallucinations and partial persistence of the persecutory delusion. A couple of days later there was complete remission of the psychotic symptoms and the patient was on the way to recovery from COVID-19 and RSV.
Conclusions
There is evidence that suggests that medications such as steroids used to treat COVID-19 and other respiratory illnesses can lead to psychotic episodes. It is very important to pay attention to possible side effects when treating with steroids and evaluate the patient history as well as suggest having a follow up visit after the hospital discharge.
Multiple Sclerosis (MS) is an autoimmune inflammatory disease that affects 1 in 1000 people. Given the association of MS to many affective disorders and specifically with Bipolar Disorder (BD), it is possible that a manic episode and an acute episode of MS may appear together. In these cases, it is difficult to decide whether it is necessary to start a corticosteroid regimen as treatment for the acute episode of MS, since it may worsen manic symptoms.
Objectives
The aim is to carry out a review of the existing information in relation to the comorbidity prevalence of MS and TB as well as the joint treatment of both illnesses, and to expose the details of a clinical case, regarding the treatment that was used in the acute psychiatry unit.
Methods
First, a search was done in PubMed database reviewing recent cases of steroid induced psychosis using the words (Multiple Sclerosis) AND (Bipolar Disorder). Subsequently, we describe the case of a 41-year-old patient who was admitted to the acute care unit from the emergency department presenting manic symptoms (megalomania, sensation of increased capacities and ideas of mystical content) associated to episodes of muscle weakness and gait disturbances. A screening Magnetic Resonance was performed in which lesions with inflammatory-demyelinating characteristics were detected, and was therefore catalogued as MS debut.
Results
After carrying out a bibliographical review, we can conclude that studies recommend the inclusion of MS within the differential diagnosis of a first manic episode (1), performing neurological examinations, complete anamnesis and imaging tests, given that there is a high prevalence ratio of the comorbidity (2.95%) (2). It has been described that the use of lithium has a calming and neuroprotective agent that may be useful (3).
Conclusions
We consider it of interest to describe the therapeutic approach to the case. After the introduction of Aripiprazole and Lithium, a short regimen of methylprednisolone in high doses was administered to treat the MS episode. When the treatment started, the patient presented a progressive improvement of the manic episode and motor symptoms. We observed that corticosteroid therapy did not worsen the manic symptoms or the patient’s evolution in this case. We intend to contribute by providing information on the joint management of these pathologies and we consider that it is necessary to continue studying this matter to be able to manage these cases in the most appropriate way.
Risk of functional impairment and progression to chronic illness in people with a first episode of psychosis (FEP) has motivated early intervention programs, showing promising results. Defining the characteristics of people with FEP at local level enables the clinicians to adjust interventional models to the reality of the population. The area 5 of Madrid (Spain) is referred to La Paz University Hospital and it serves a catchment area of roughly 527,000 people.
Objectives
We aim to identify sociodemographic and clinical characteristics of patients in the area 5 of Madrid (Spain) who meet the criteria of FEP.
Methods
A descriptive retrospective study including 179 people (age range 18-40 years) who were attended in mental health services of La Paz University Hospital (area 5 of Madrid, Spain), between January 2019 and May 2020, having suffered a psychotic episode in the last five years.
Results
The average age of people with FEP was 29.32 years, with a higher proportion of men (62%). The mean duration of untreated psychosis (DUP) was 3.64 months and 47% of patients consume cannabis. We found disparities in DUP among the different districts in the area and we also observed differences depending on the district for inclusion in rehabilitation programs or psychotherapy. The following averages were obtained for the aggregate sample: 1.01 hospitalization/year, 1.42 emergency room visits/year, 1.81 years of illness and a mean dosage equivalent to olanzapine 6.75 mg/day. The incidence of psychosis in our area has been 7.01 cases per 100000 inhabitants/year.
Conclusions
The incidence of psychosis has been as expected according to data recorded at previous studies in Spain. The results obtained in our sample have included a lower DUP and a higher use of cannabis than those described in the literature. We have also found differences when observing the inclusion of patients in different treatments (psychotherapy, rehabilitation), which may be related to the differences in the DUP by districts. Further exploration in this field is needed to draw causal conclusions.
Two hundred and ten pigs were reared in three groups (according to genotype) under enriched conditions of large open-front sawdust-bedded barns. Eight hundred and twenty pigs were reared under standard conditions of small 15-animal pens in a conventional barn with partially slatted floors and natural ventilation. Production parameters including percentage mortality, feed conversion rate and average daily weight gain were calculated at the end of the fattening period. Stomachs, limbs and lungs were examined at slaughter in order to compare the number and severity of lesions between the enriched environment groups and the standard environment group. There was a significantly greater number of esophagogastric lesions in the standard environment group than in the enriched environment groups. No esophagogastric ulcers were observed in any pigs from the enriched groups, while 17.5% of stomachs from pigs in the standard environment group displayed this condition. There were no significant differences in the number of lung lesions associated with enzootic pneumonia between pigs from the standard and enriched environment groups. The limbs of animals reared in the standard environment had more lesions, especially in floor-contact areas, than those reared in the enriched environment (23.84% versus 1.08%). The production parameters measured were improved in the pigs from the enriched environment. These results suggest that the welfare of fattening pigs may be improved by the provision of enrichment in their housing environment. Evaluation of esophagogastric ulceration could be a useful indicator of welfare in pigs.
We aim to uncover the structure of the continuum and broad emission line (BEL) emitting regions in the gravitationally lensed quasar SDSS J1004+4112 through unique microlensing signatures. Analyzing 20 spectroscopic observations from 2003 to 2018, we study the striking deformations of various BEL profiles and determine the sizes of their respective emitting regions. We use the emission line cores as a baseline for no microlensing and then apply Bayesian methods to derive the sizes of the Lyα, Si IV, C IV, C III], and Mg II emitting regions, as well as of the underlying continuum-emitting sources. We find that the sizes of the emitting regions for the BELs are a few light-days across, notably smaller than in typical lensed quasars. The asymmetric distortions observed in the BELs suggest that the broad-line region lacks spherical symmetry and is likely confined to a plane. The inferred continuum emitting region sizes are larger than predictions based on standard thin-disk theory by a factor of ∼ 4. We find that the size-wavelength relation is in agreement with that of a geometrically thin and optically thick accretion disk.
Long-term COVID-19 effects has been recently described as persistent and prolonged symptoms after an acute and severe SARS-COV-2 (1). An important concern is that the sequelae of severe COVID-19 may suppose a substantial outpatient 's burden for the specialized services in reopening pandemic phase (2).
Objectives
To describe the frequency of mental health service use in COVID-19 hospitalized patients after discharge and to estimate the costs associated to the post- discharge consultations.
Methods
We used a 1-year follow-up cohort of 1455 COVID-19 inpatients hospitalized in La Paz University Hospital of Madrid, Spain between March 16th and April 15th, 2020. Data were retrieved from Psychiatry Service (PS) electronic health records and we described the frequency of mental health reason for consultation. We used information published by the Madrid health Office to estimate the cost of initial and following appointments.
Results
Our sample consisted of 1,455 patients admitted with a COVID-19 diagnosis between March 16th and April 15th, 2020, and then discharged. Roughly half of them were men (776, 53%), 238 (16%) had a prior history of mental health problems, and 44 (3%) died. 193 participants (13%) visited the mental health department after being discharged. The total cost was estimated in 103,581 USD, of which two-thirds corresponded to patients with prior history of mental health problems.
Conclusions
Our results indicate that the mental health burden of severe COVID-19 inpatient s after discharge was substantial during the first year of follow-up. This generate important economic impact to mental health providers and society at large.
The extent to which structural gender inequality contributes to macro-level differences in postpartum depression (PPD) remains largely unknown.
Objectives
To examine the association of structural gender inequalities with national-level prevalence estimates of PPD symptoms.
Methods
Meta-analytically derived national-level estimates for the prevalence of PPD symptoms – based on the Edinburgh Postnatal Depression Scale (EPDS) – were combined with economic (e.g., income inequality), health (e.g., infant mortality rate), sociodemographic (e.g., urban population), and structural gender inequality variables (e.g., abortion policies) for 40 countries (276 primary studies). Data came from a prior meta-analysis on PPD prevalence and international agencies (e.g., UNICEF). Meta-regression techniques and traditional p-value based stepwise procedures, complemented with a Bayesian model averaging approach, were used for a robust selection of variables associated with national-level PPD symptom prevalence. Sensitivity analyses excluded primary studies with small sample sizes or countries lacking evidence for psychometric properties of the EPDS.
Results
Income inequality (β = 0.04, 95% CI = 0.02 to 0.07) and abortion policies (β = 0.02, 95% CI = 0.00 to 0.03) were the only variables included in the final, adjusted model, accounting for 60.7% of the variance in PPD symptoms across countries. Gradual liberalizations of abortion policies were associated with a 2% decrease in national-level PPD symptom prevalence. Results were robust to sensitivity analyses.
Conclusions
Structural gender inequalities might be social determinants of PPD, as the liberalization of abortion policies seem to impact women’s perinatal mental health on a population level. More research on structural gender inequality is needed to guide policy and practice.
Background: Eye movements reveal neurodegenerative disease processes due to overlap between oculomotor circuitry and disease-affected areas. Characterizing oculomotor behaviour in context of cognitive function may enhance disease diagnosis and monitoring. We therefore aimed to quantify cognitive impairment in neurodegenerative disease using saccade behaviour and neuropsychology. Methods: The Ontario Neurodegenerative Disease Research Initiative recruited individuals with neurodegenerative disease: one of Alzheimer’s disease, mild cognitive impairment, amyotrophic lateral sclerosis, frontotemporal dementia, Parkinson’s disease, or cerebrovascular disease. Patients (n=450, age 40-87) and healthy controls (n=149, age 42-87) completed a randomly interleaved pro- and anti-saccade task (IPAST) while their eyes were tracked. We explored the relationships of saccade parameters (e.g. task errors, reaction times) to one another and to cognitive domain-specific neuropsychological test scores (e.g. executive function, memory). Results: Task performance worsened with cognitive impairment across multiple diseases. Subsets of saccade parameters were interrelated and also differentially related to neuropsychology-based cognitive domain scores (e.g. antisaccade errors and reaction time associated with executive function). Conclusions: IPAST detects global cognitive impairment across neurodegenerative diseases. Subsets of parameters associate with one another, suggesting disparate underlying circuitry, and with different cognitive domains. This may have implications for use of IPAST as a cognitive screening tool in neurodegenerative disease.
The role of mass loss from massive stars, especially episodic mass loss, is one of the outstanding open questions facing stellar evolution theory. Multiple lines of evidence are pointing to violent, episodic mass-loss events being responsible for removing a large part of the massive stellar envelope, especially in low-metallicity galaxies. The ERC ASSESS project aims to determine whether episodic mass loss is a dominant process in the evolution of the most massive stars by conducting the first extensive, multi-wavelength survey of evolved massive stars in the nearby Universe. The project hinges on the fact that mass-losing stars form dust and are bright in the mid-infrared. We aim to investigate the properties of evolved targets in nearby galaxies and estimate the amount of ejected mass, which will constrain evolutionary models. In this work we present some of our first observational results from the galaxies NGC 6822 and IC 10 obtained with OSIRIS (GTC).
Episodic mass loss is not understood theoretically, neither accounted for in state-of-the-art models of stellar evolution, which has far-reaching consequences for many areas of astronomy. We introduce the ERC-funded ASSESS project (2018-2024), which aims to determine whether episodic mass loss is a dominant process in the evolution of the most massive stars, by conducting the first extensive, multi-wavelength survey of evolved massive stars in the nearby Universe. It hinges on the fact that mass-losing stars form dust and are bright in the mid-infrared. We aim to derive physical parameters of ∼1000 dusty, evolved massive stars in ∼25 nearby galaxies and estimate the amount of ejected mass, which will constrain evolutionary models, and quantify the duration and frequency of episodic mass loss as a function of metallicity. The approach involves applying machine-learning algorithms to select dusty, luminous targets from existing multi-band photometry of nearby galaxies. We present the first results of the project, including the machine-learning methodology for target selection and results from our spectroscopic observations so far. The emerging trend for the ubiquity of episodic mass loss, if confirmed, will be key to understanding the explosive early Universe and will have profound consequences for low-metallicity stars, reionization, and the chemical evolution of galaxies.
Despite extensive paleoenvironmental research on the postglacial history of the Kenai Peninsula, Alaska, uncertainties remain regarding the region's deglaciation, vegetation development, and past hydroclimate. To elucidate this complex environmental history, we present new proxy datasets from Hidden and Kelly lakes, located in the eastern Kenai lowlands at the foot of the Kenai Mountains, including sedimentological properties (magnetic susceptibility, organic matter, grain size, and biogenic silica), pollen and macrofossils, diatom assemblages, and diatom oxygen isotopes. We use a simple hydrologic and isotope mass balance model to constrain interpretations of the diatom oxygen isotope data. Results reveal that glacier ice retreated from Hidden Lake's headwaters by ca. 13.1 cal ka BP, and that groundwater was an important component of Kelly Lake's hydrologic budget in the Early Holocene. As the forest developed and the climate became wetter in the Middle to Late Holocene, Kelly Lake reached or exceeded its modern level. In the last ca. 75 years, rising temperature caused rapid changes in biogenic silica content and diatom oxygen isotope values. Our findings demonstrate the utility of mass balance modeling to constrain interpretations of paleolimnologic oxygen isotope data, and that groundwater can exert a strong influence on lake water isotopes, potentially confounding interpretations of regional climate.