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McMurdo Dry Valley lake edge ‘moats’: the ecological intersection between terrestrial and aquatic polar desert habitats
- Michael S. Stone, Shawn P. Devlin, Ian Hawes, Kathleen A. Welch, Michael N. Gooseff, Cristina Takacs-Vesbach, Rachael Morgan-Kiss, Byron J. Adams, J.E. Barrett, John C. Priscu, Peter T. Doran
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- Antarctic Science , First View
- Published online by Cambridge University Press:
- 19 April 2024, pp. 1-17
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Aquatic ecosystems - lakes, ponds and streams - are hotspots of biodiversity in the cold and arid environment of Continental Antarctica. Environmental change is expected to increasingly alter Antarctic aquatic ecosystems and modify the physical characteristics and interactions within the habitats that they support. Here, we describe physical and biological features of the peripheral ‘moat’ of a closed-basin Antarctic lake. These moats mediate connectivity amongst streams, lake and soils. We highlight the cyclical moat transition from a frozen winter state to an active open-water summer system, through refreeze as winter returns. Summer melting begins at the lakebed, initially creating an ice-constrained lens of liquid water in November, which swiftly progresses upwards, creating open water in December. Conversely, freezing progresses slowly from the water surface downwards, with water at 1 m bottom depth remaining liquid until May. Moats support productive, diverse benthic communities that are taxonomically distinct from those under the adjacent permanent lake ice. We show how ion ratios suggest that summer exchange occurs amongst moats, streams, soils and sub-ice lake water, perhaps facilitated by within-moat density-driven convection. Moats occupy a small but dynamic area of lake habitat, are disproportionately affected by recent lake-level rises and may thus be particularly vulnerable to hydrological change.
25 High-resolution MRI Reveals Selective Patterns of Hippocampal Subfield Atrophy in Focal Epilepsy
- Adam Schadler, Erik Kaestner, Alena Stasenko, Christine N. Smith, Catherine Tallman, Nigel P. Pedersen, Shahin Hakimian, Michelle S. Kim, Daniel J Peterson, Thomas J. Grabowski, Daniel L. Drane, Carrie R. McDonald
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- Journal of the International Neuropsychological Society / Volume 29 / Issue s1 / November 2023
- Published online by Cambridge University Press:
- 21 December 2023, pp. 25-26
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Objective:
Hippocampal pathology is a consistent feature in persons with temporal lobe epilepsy (TLE) and a strong biomarker of memory impairment. Histopathological studies have identified selective patterns of cell loss across hippocampal subfields in TLE, the most common being cellular loss in the cornu ammonis 1 (CA1) and dentage gyrus (DG). Structural neuroimaging provides a non-invasive method to understand hippocampal pathology, but traditionally only at a whole-hippocampal level. However, recent methodological advances have enabled the non-invasive quantification of subfield pathology in patients, enabling potential integration into clinical workflow. In this study, we characterize patterns of hippocampal subfield atrophy in patients with TLE and examine the associations between subfield atrophy and clinical characteristics.
Participants and Methods:High-resolution T2 and T1-weighted MRI were collected from 31 participants (14 left TLE; 6 right TLE; 11 healthy controls [HC], aged 18-61 years). Reconstructions of hippocampal subfields and estimates of their volumes were derived using the Automated Segmentation of Hippocampal Subfields (ASHS) pipeline. Total hippocampal volume was calculated by combining estimates of the subfields CA1-3, DG, and subiculum. To control for variations in head size, all volume estimates were divided by estimates of total brain volume. To assess disease effects on hippocampal atrophy, hippocampi were recoded as either ipsilateral or contralateral to the side of seizure focus. Two sample t-tests at a whole-hippocampus level were used to test for ipsilateral and contralateral volume loss in patients relative to HC. To assess whether we replicated the selective histopathological patterns of subfield atrophy, we carried out mixed-effects ANOVA, coding for an interaction between diagnostic group and hippocampal subfield. Finally, to assess effects of disease load, non-parametric correlations were performed between subfield volume and age of first seizure and duration of illness.
Results:Patients had significantly smaller total ipsilateral hippocampal volume compared with HC (d=1.23, p<.005). Contralateral hippocampus did not significantly differ between TLE and HC. Examining individual subfields for the ipsilateral hemisphere revealed significant main-effects for group (F(1, 29)=8.2, p<0.01), subfields (F(4, 115)=550.5, p<0.005), and their interaction (F(4, 115)=8.1, p<0.001). Post-hoc tests revealed that TLE had significantly smaller volume in the ipsilateral CA1 (d=-2.0, p<0.001) and DG (d = -1.4, p<0.005). Longer duration of illness was associated with smaller volume of ipsilateral CA2 (p=-0.492, p<0.05) and larger volume of contralateral whole-hippocampus (p=0.689, p<0.001), CA1 (p=0.614, p < 0.005), and DG (p=0.450, p<0.05).
Conclusions:Histopathological characterization after surgery has revealed important associations between hippocampal subfield cell loss and memory impairments in patients with TLE. Here we demonstrate that non-invasive neuroimaging can detect a pattern of subfield atrophy in TLE (i.e., CA1/DG) that matches the most common form of histopathologically-observed hippocampal sclerosis in TLE (HS Type 1) and has been linked directly to both verbal and visuospatial memory impairment. Finally, we found evidence that longer disease duration is associated with larger contralateral hippocampal volume, driven by increases in CA1 and DG. This may reflect subfield-specific functional reorganization to the unaffected brain tissue, a compensatory effect which may have important implications for patient function and successful treatment outcomes.
Efficacy of maintenance electroconvulsive therapy in recurrent depression: a case series
- G. Guerra Valera, Ó. Martín Santiago, M. Esperesate Pajares, Q. D. L. de la Viuda, A. A. Gonzaga Ramírez, C. Vallecillo Adame, C. de Andrés Lobo, T. Jiménez Aparicio, N. Navarro Barriga, B. Rodríguez Rodríguez, M. Fernández Lozano, M. J. Mateos Sexmero, A. Aparicio Parras, M. Calvo Valcárcel, M. A. Andreo Vidal, P. Martínez Gimeno, M. P. Pando Fernández, M. D. L. Á. Guillén Soto
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- European Psychiatry / Volume 66 / Issue S1 / March 2023
- Published online by Cambridge University Press:
- 19 July 2023, p. S832
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Introduction
Maintenance electroconvulsive therapy (mECT) is an option in the treatment of affective disorders which progress is not satisfactory. It is certainly neglected and underused during the clinical practice.
ObjectivesTo evaluate the efficacy of mECT in reducing recurrence and relapse in recurrent depression within a sample of three patients.
MethodsWe followed up these patients among two years since they received the first set of electroconvulsive sessions. We applied the Beck Depression Inventory (BDI) in the succesives consultations for evaluating the progress.
ResultsThe three patients were diagnosed with Recurrent Depressive Disorder (RDD). One of them is a 60 year old man that received initially a cycle of 12 sessions; since then he received 10 maintenance sessions. Other one is a 70 year old woman that received initially a cycle of 10 sessions; since then she received 6 maintenance sessions. The last one is a 55 year old woman that received initially a cycle of 14 sessions; since then she received 20 maintenance sessions.
All of them showed a significant reduction in depressive symptoms evaluated through BDI and clinical examination. In the first case, we found a reduction in the BDI from the first consultation to the last that goes from 60 to 12 points; in the second case, from 58 to 8 points; and in the last case, from 55 to 10 points. The main sections that improved were emotional, physical and delusional.
As side-effects of the treatment, we found anterograde amnesia, lack of concentration and loss of focus at all of them.
ConclusionsWe find mECT as a very useful treatment for resistant cases of affective disorders like RDD.
It should be considered as a real therapeutic option when the first option drugs have been proved without success.
Disclosure of InterestNone Declared
UNTIL IT BURSTS OR ALL OF US BURST. A SCHIZOTYPICAL CASE.
- B. Rodríguez Rodríguez, N. Navarro Barriga, M. Fernández Lozano, M. J. Mateos Sexmero, M. A. Andreo Vidal, M. Calvo Valcárcel, P. Martínez Gimeno, M. P. Pando Fernández, A. Aparicio Parras, M. D. L. Á. Guillén Soto, T. Jiménez Aparicio, M. D. C. Vallecillo Adame, C. de Andrés Lobo, A. A. Gonzaga Ramírez, G. Guerra Valera, M. Queipo de Llano de la Viuda, M. Esperesate Pajares
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- European Psychiatry / Volume 66 / Issue S1 / March 2023
- Published online by Cambridge University Press:
- 19 July 2023, p. S967
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Introduction
Schizotypal disorder is conceptualized as a stable personality pathology (Cluster A) and as a latent manifestation of schizophrenia. It can be understood as an attenuated form of psychosis or high-risk mental state, which may precede the onset of schizophrenia or represent a more stable form of psychopathology that doesn’t necessarily progress to psychosis.
ObjectivesTo exemplify the continuum of psychosis
MethodsReview of scientific literature based on a relevant clinical case.
Results39-year-old male living with his parents. He started studying philosophy. He is a regular cannabis user and has an aunt with schizophrenia. He’s admitted to psychiatry for behavioral disturbance in public. He refers to having been hearing a beeping noise in his street for months, what he interprets as a possible way of being watched due to his past ideology. Without specifying who and why, he sometimes shouts “until it bursts” to stop the noise and he thinks that his neighbours alerted the police about his behavior. During the interview he alludes to Milgram’s experiment, saying that throughout history there have been crimes against humanity and those who pointed them out were labeled “crazy”. His father refers that he has always been “strange” and with certain extravagant revolutionary ideas and thoughts. He doesn’t maintain social relationships and dedicates himself to reading and writing.
ConclusionsIt’s important to understand psychosis as a continuum to advance the understanding of etiology, pathophysiology and resilience of psychotic disorders and to develop strategies for prevention and early intervention
Disclosure of InterestNone Declared
Delirious episode secondary to rotigotine: the psychotic patch
- M. A. Andreo Vidal, M. Calvo Valcárcel, P. Martínez Gimeno, P. Pando Fernández, B. Rodríguez Rodríguez, N. Navarro Barriga, M. Fernández Lozano, M. J. Mateos Sexmero, T. Jiménez Aparicio, M. D. C. Valdecillo Adame, C. de Andrés Lobo, G. Guerra Valera, M. Queipo de Llano de la Viuda, A. A. Gonzaga Ramirez, M. D. L. Á. Guillén Soto, A. Aparicio Parras, M. Esperesate Pajares
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- European Psychiatry / Volume 66 / Issue S1 / March 2023
- Published online by Cambridge University Press:
- 19 July 2023, p. S626
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Introduction
There is a fine line separating psychiatry and neurology. Most movement disorders can have psychiatric symptoms, not only those caused by the disease itself, but also those induced by the drugs used to treat them.
ObjectivesPresentation of a clinical case about a patient diagnosed with Parkinson’s disease presenting a several-month-long delirious episode due to dopaminergic drugs.
MethodsLiterature review on drug-induced psychosis episodes in Parkinson’s disease.
ResultsA 57-year-old patient with diagnosis of Parkinson’s disease for six years, who went to the emergency room accompanied by his wife due to delirious ideation. He was being treated with levodopa, carbidopa and rasagiline for years, and rotigotine patches whose dosage was being increased over the last few months.
His wife reported celotypical clinical manifestations and multiple interpretations of different circumstances occurring around her. He chased her on the street, had downloaded an app to look for a second cell phone because he believed she was cheating on him, and was obsessed with sex. He had no psychiatric background. It was decided to prescribe quetiapine.
The following day, he returned because he refused to take the medication since he thought he was going to be put to sleep or poisoned. It was decided to admit him to Psychiatry.
During the stay, rasagiline and rotigotine were suspended. Olanzapine and clozapine were introduced, with behavioral improvement and distancing from the psychotic symptoms which motivated the admission. The patient was also motorically stable. Although levodopa is best known for causing psychotic episodes, the symptons were attributed to rotigotine patches for temporally overlapping the dose increase.
ConclusionsPsychiatric symptoms are the third most frequent group of complications in Parkinson’s disease after gastrointestinal complications and abnormal movements. All medication used to control motor disorders can lead to psychosis, not only dopaminergics, but also selegiline, amantadine and anticholinergics.
Excessive stimulation of mesocortical and mesolimbic dopaminergic pathways can lead to psychosis, which is the most common psychiatric problem related to dopaminergic treatment.
In the face of a psychotic episode, antiparkinsonian drugs which are not strictly necessary for motor control should be withdrawn. If this is not sufficient, levodopa dose should be reduced, considering the side effects that may occur. When the adjustment of antiparkinsonian treatment is not effective, neuroleptics, especially quetiapine or clozapine, should be administered. In a recent study, pimavanserin, a serotonin 5-HT2 antagonist, was associated with approximately 35% lower mortality than atypical antipsychotic use during the first 180 days of treatment in community-dwelling patients.
Medication should always be tailor-made to suit each patient and we usually have to resort to lowering or withdrawing the dopaminergic medication.
Disclosure of InterestNone Declared
Bipolar disorder and substance use: Risk factors and prognosis
- M. Fernández Lozano, B. Rodríguez Rodríguez, M. J. Mateos Sexmero, N. Navarro Barriga, C. Vallecillo Adame, C. de Andrés Lobo, T. Jimenez Aparicio, M. Queipo de Llano de la Viuda, G. Guerra Valera, A. A. Gonzaga Ramírez, M. P. Pando Fernández, M. Calvo Valcárcel, M. A. Andreo Vidal, P. Martínez Gimeno
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- European Psychiatry / Volume 66 / Issue S1 / March 2023
- Published online by Cambridge University Press:
- 19 July 2023, p. S704
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Introduction
Bipolar disorder comorbidity rates are the highest among the major mental disorders. In addition to other intoxicants, alcohol is the most abused substance because it is socially accepted and can be legally bought and consumed. Estimates are between 40-70% with male predominance, which further influences the severity with a more complicated course of both disorders.
ObjectivesThe objective of this article is to highlight the impact of substance use on the course and prognosis of bipolar disorder, as well as to make a differential diagnosis of a manic episode in this context.
MethodsBibliographic review of scientific literature based on a relevant clinical case.
ResultsWe present the case of a 45-year-old male patient. Single with no children. Unemployed. History of drug use since he was young: alcohol, cannabis and amphetamines. Diagnosed with bipolar disorder in 2012 after a manic episode that required hospital admission. During his evolution he presented two depressive episodes that required psychopharmacological treatment and follow-up by his psychiatrist of reference. Since then, he has been consuming alcohol and amphetamines occasionally, with a gradual increase until it became daily in the last month. He went to the emergency department for psychomotor agitation after being found in the street. He reported feeling threatened by a racial group presenting accelerated speech, insomnia and increased activity.
ConclusionsThe presence of substance abuse complicates the clinical presentation, treatment and development of bipolar disorder. It is associated with a worse prognosis with multiple negative consequences including worsening symptom severity, increased risk of suicide and hospitalization, increased medical morbidity and complication of social problems. In addition, this comorbidity delays both the diagnosis and treatment, by masking the symptoms, and making more difficult an adequate differential diagnosis.
Disclosure of InterestNone Declared
I don’t know where I’m going or where I come from. Self-disorders in schizophrenia.
- M. D. C. Vallecillo Adame, L. Rodríguez Andrés, C. de Andrés Lobo, T. Jimenez Aparicio, M. Queipo de Llano de la Viuda, G. Guerra Valera, A. A. Gonzaga Ramirez, M. Fernández Lozano, M. J. Mateos Sexmero, N. Navarro Barriga, B. Rodríguez Rodríguez, M. P. Pando Fernández, M. Calvo Valcárcel, P. Martínez Gimeno, M. A. Andreo Vidal, I. D. L. M. Santos Carrasco
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- European Psychiatry / Volume 66 / Issue S1 / March 2023
- Published online by Cambridge University Press:
- 19 July 2023, pp. S1069-S1070
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Introduction
In the early stages of schizophrenia the person experiences feelings of strangeness about themselves, difficulty in making sense of things and difficulty in interacting with their environment. Based on this, self-disorder assessment instruments have been developed and empirical studies have been conducted to assess people at risk of developing a schizophrenia spectrum disorder. These studies show that self-disorders are found in pre-psychotic stages and that their manifestation can predict the transition to schizophrenia spectrum disorders.
ObjectivesWe present the case of a patient with multiple diagnoses and mainly dissociative symptoms who, after years of evolution, was diagnosed with schizophrenia.
MethodsBibliographic review including the latest articles in Pubmed about self-disorders and schizophrenia.
ResultsWe present the clinical case of a 51-year-old woman with a long history of follow-up in mental health consultations and with multiple hospital admissions to the psychiatric unit, with several diagnoses including: dissociative disorder, histrionic personality disorder, adaptive disorder unspecified psychotic disorder and, finally, schizophrenia. The patient during the first hospital admissions showed a clinical picture of intense anxiety, disorientation and claiming to be a different person. The patient related these episodes to stressors she had experienced, and they improved markedly after a short period of hospital admission. Later, psychotic symptoms appeared in the form of auditory and visual hallucinations and delusional ideation, mainly of harm, so that after several years of follow-up and study in mental health consultations and in the psychiatric day hospital, she was diagnosed with schizophrenia and treatment with antipsychotics was introduced, with a marked clinical improvement being observed.
ConclusionsIt is important to take into account this type of symptoms (self-disorders), as they allow the identification of individuals in the early stages of the disorder and create the opportunity for early therapeutic interventions.
Disclosure of InterestNone Declared
PEAKS AND VALLEYS: BIPOLAR DISORDER, RAPID CYCLERS AND ENERGY DRINKS CONSUMPTION
- M. Calvo Valcárcel, M. A. Andreo Vidal, P. Martinez Gimeno, P. Pando Fernández, B. Rodriguez Rodriguez, N. Navarro Barriga, M. Fernández Lozano, M. J. Mateos Sexmero, M. D. C. Vallecillo Adame, T. Jimenez Aparicio, C. de Andres Lobo, M. Queipo de Llano de la Viuda, A. A. Gonzaga Ramirez, G. Guerra Valera
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- European Psychiatry / Volume 66 / Issue S1 / March 2023
- Published online by Cambridge University Press:
- 19 July 2023, pp. S702-S703
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Introduction
Bipolar Disorder (BD) is considered a serious mental disorder characterized by a changing mood that fluctuates between two completely opposite poles. It causes pathological and recurrent mood swings, alternating periods of exaltation and grandiosity with periods of depression. We talk about rapid cyclers when four or more manic, hypomanic or depressive episodes have occurred within a twelve-month period. Mood swings can appear rapidly. Approximately half of the people with bipolar disorder may develop rapid cycling at some point.
ObjectivesPresentation of a clinical case about a patient with Bipolar Disorder with rapid cycling and poor response to treatment.
MethodsReview of the scientific literature based on a clinical case.
Results33-year-old male, single, living with his mother, under follow-up by mental health team since 2012. First debut of manic episode in 2010. The patient has filed multiple decompensations related to consumption of toxics (alcohol and cannabis). Currently unemployed. He attended to the emergency service in June 2022 accompanied by his mother, who reported that he was restless. The patient refers that he has interrupted the treatment during the vacations, having sleep rhythm disorder with abuse of caffeine drinks. Currently the patient does not recognize any consumption.The patient reports that during the village festivals he felt very energetic, occasionally consuming drinks rich in taurine and sugars, even having conflicts with people of the village. Finally, the patient was stabilized with Lithium 400 mg and Olanzapine. In September, the patient returned to the emergency service on the recommendation of his referral psychiatrist due to therapeutic failure. The only relevant finding we observed in the analytical determinations were low lithium levels (0.4 mEq/L). The transgression of sleep rhythms and the abuse of psychoactive substances required the admission of the patient to optimize the treatment (Clozapine, Lithium, Valproic Acid). At discharge, he is euthymic, has not presented behavioral alterations and is resting well. Finally, it was decided that the patient should go to the Convalescent Center to continue treatment and achieve psychopathological stability.
ConclusionsBipolar disorder is an important mental illness, having an incidence of 1.2%, being responsible for 20% of all mood disorders. Therefore, it is important to perform an adequate and individualized follow-up of each patient. Treatment with mood stabilizers tries to improve and prevent manic and depressive episodes, improving chronicity and trying to make the long-term evolution as good as possible, being important psychoeducation and psychotherapy.
Disclosure of InterestNone Declared
Late diagnosis of attention deficit hyperactivity disorder and cocaine abuse
- C. De Andrés Lobo, C. Vallecillo Adame, T. Jiménez Aparicio, M. Queipo de Llano de la Viuda, G. Guerra Valera, A. A. Gonzaga Ramírez, M. Fernández Lozano, N. Navarro Barriga, M. J. Mateos Sexmero, B. Rodríguez Rodríguez, M. Calvo Valcárcel, M. Andreo Vidal, M. P. Pando Fernández, P. Martínez Gimeno, I. D. L. M. Santos Carrasco, J. I. Gonçalves Cerejeira, A. Rodríguez Campos
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- European Psychiatry / Volume 66 / Issue S1 / March 2023
- Published online by Cambridge University Press:
- 19 July 2023, pp. S335-S336
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Introduction
Adult ADHD diagnosis sometimes represents a challenge for the clinician, due to the comorbid psychiatric diseases that are often associated and which complicate de recognition of the primary symptoms of ADHD. The prevalence of ADHD in adult populations is 2’5% and it is a relevant cause of functional impairment.
ObjectivesPresentation of a clinical case of a male cocaine user diagnosed with adult ADHD.
MethodsLiterature review on adult ADHD and comorbid substance abuse.
ResultsA 43-year-old male who consulted in the Emergency Department due to auditory hallucinosis in the context of an increase in his daily cocaine use. There were not delusional symptoms associated and judgment of reality was preserved. Treatment with olanzapine was started and the patient was referred for consultation. In psychiatry consultations, he did not refer sensory-perceptual alterations anymore, nor appeared any signals to suspect so, and he was willing to abandon cocaine use after a few appointments. He expressed some work concerns, highlighting that in recent months, in the context of a greater workload, he had been given several traffic tickets for “distractions.” His wife explained that he had always been a inattentive person (he forgets important dates or appointments) and impulsive, sometimes interrupting conversations. In the Barkley Adult ADHD Rating Scale he scored 32 points.
He was diagnosed with adult ADHD and treatment with extended-release methylphenidate was started with good tolerance and evolution, with improvement in adaptation to his job and social environment. Since then, the patient has moderately reduced the consumption of drugs, although he continues to use cocaine very sporadically.
ConclusionsEarly detection of ADHD and its comorbidities has the potential to change the course of the disorder and the morbidity that will occur later in adults. Comorbidity in adult ADHD is rather the norm than the exception, and it renders diagnosis more difficult. The most frequent comorbidities are usually mood disorders, substance use disorders, and personality disorders. Treatment of adult ADHD consists mainly of pharmacotherapy supported by behavioral interventions. When ADHD coexists with another disorder, the one that most compromises functionality will be treated first and they can be treated simultaneously. The individual characteristics of each patient must be taken into account to choose the optimal treatment.
Disclosure of InterestNone Declared
“The cat and the calcium”. A case of delirium secondary to hypercalcaemia.
- T. Jiménez Aparicio, C. Vallecillo Adame, C. de Andrés Lobo, G. Medina Ojeda, M. Queipo de Llano de la Viuda, A. A. Gonzaga Ramírez, G. Guerra Valera, M. Fernández Lozano, M. J. Mateos Sexmero, B. Rodríguez Rodríguez, N. Navarro Barriga, M. A. Andreo Vidal, M. Calvo Valcárcel, P. Martínez Gimeno, M. P. Pando Fernández, I. D. L. M. Santos Carrasco, J. I. Gonçalves Cerejeira
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- European Psychiatry / Volume 66 / Issue S1 / March 2023
- Published online by Cambridge University Press:
- 19 July 2023, pp. S946-S947
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Introduction
Interconsultation with the psychiatry service is frequently requested from other specialties for the assessment and treatment of patients who present neuropsychiatric symptoms secondary to organic alterations. On the other hand (and in relation to this case), within the possible causes for the elevation of calcaemia figures, the most frequent are hyperparathyroidism and neoplasms, representing between these two entities 90% of cases (1).
Among the organic mental disorders, Delirium stands out, with an approximate prevalence between 1 and 2% (general population), which increases in hospitalized and elderly patients (2).
ObjectivesPresentation of a clinical case about a patient with delirium secondary to hypercalcemia, with hallucinations and behavioral disturbance.
MethodsBibliographic review including the latest articles in Pubmed about delirium (causes and treatment) and hypercalcaemia secondary to neoplasms.
ResultsWe present a 52-year-old male patient, who went to the emergency room accompanied by his wife, due to behavioral alteration. Two days before, he had been evaluated by Neurology, after a first epileptic crisis (with no previous history) that resolved spontaneously. At that time, it was decided not to start antiepileptic treatment.
The patient reported that he had left his house at midnight, looking for a cat. As he explained, this cat had appeared in his house and had left his entire bed full of insects. His wife denied that this had really happened, and when she told the patient to go to the emergency room, he had become very upset.
As background, the patient used to consume alcohol regularly, so the first hypothesis was that this was a withdrawal syndrome. However, although the consumption was daily, in recent months it was not very high, and at that time no other symptoms compatible with alcohol withdrawal were observed (tremor, tachycardia, sweating, hypertension…).
We requested a general blood test and a brain scan. The only relevant finding was hypercalcaemia 12.9mg/dL (which could also be the origin of the previous seizure). It was decided to start treatment with Diazepam and Tiapride in the emergency room, with serum perfusion, and keep under observation. After several hours, the patient felt better, the hallucinations disappeared, and calcium had dropped to 10.2mg/dL. A preferential consultation was scheduled, due to suspicion that the hypercalcaemia could be secondary to a tumor process.
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ConclusionsIt is important to rule out an organic alteration in those patients who present acute psychiatric symptoms. Hypercalcaemia is frequently associated with tumor processes (1) due to secretion of PTH-like peptide (4), so a complete study should be carried out in these cases.
Delirium has a prevalence between 1 and 2% in the general population (2).
Psychopharmacological treatment is used symptomatically, with antipsychotics (3). For the episode to fully resolve, the underlying cause must be treated.
Disclosure of InterestNone Declared
“Keeping an eye on amylase”. Side effects of antidepressants
- T. Jiménez Aparicio, G. Medina Ojeda, A. Rodríguez Campos, L. Rodríguez Andrés, C. Vallecillo Adame, C. De Andrés Lobo, M. Queipo de Llano de la Viuda, G. Guerra Valera, A. A. Gonzaga Ramírez, M. J. Mateos Sexmero, M. Fernández Lozano, B. Rodríguez Rodríguez, N. Navarro Barriga, M. P. Pando Fernández, P. Martínez Gimeno, M. Calvo Valcárcel, M. A. Andreo Vidal
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- European Psychiatry / Volume 66 / Issue S1 / March 2023
- Published online by Cambridge University Press:
- 19 July 2023, p. S831
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Introduction
Both in consultations with the general practitioner and with the psychiatrist, antidepressants are one of the most used drugs (1). These have multiple indications, and there are different groups according to their mechanism of action. In relation to this case, we are going to talk about Venlafaxine, a dual-type antidepressant, that is, it inhibits the reuptake of serotonin and norepinephrine. One of the most common side effects is digestive discomfort, which usually resolves after a few weeks (2). However, we should not ignore these symptoms, since they can hide something more serious.
ObjectivesPresentation of a clinical case on a patient who presented an increase in pancreatic amylase after starting treatment with Venlafaxine.
MethodsBibliographic review including the latest articles in Pubmed on side effects of antidepressant treatment, and more specifically at the gastrointestinal level (in this case we will talk about pancreatitis).
ResultsWe present the case of a 49-year-old woman, who was hospitalized 2 years ago, due to a first depressive episode. During this admission, psychopharmacological treatment was started for the first time, on that occasion with a selective serotonin reuptake inhibitor (SSRI), treatment of first choice (3). The patient had no side effects at that time, but the response was very modest, so it was decided to replace that antidepressant with Venlafaxine (with dual action), up to 150mg. The depressive symptoms improved markedly, however the patient began to feel digestive discomfort (which at first did not seem to be of great importance). A general analysis was performed, in which an increase in lipase (978 U/L) and amylase (528 U/L) was detected. An echoendoscopy, an abdominal scan, and a magnetic resonance cholangiography were performed; Pancreatitis secondary to drugs was suspected (a severe condition). Luckily, no significant lesions were found in the tests, and the levels of amylase and lipase decreased when Venlafaxine treatment was withdrawn (without reaching the normal range). The patient was discharged and continued to attend consultations. In the last control, amylase had dropped to 225 U/L. His abdominal pain disappeared. Treatment with Vortioxetine (a multimodal antidepressant) was started, however the amylase levels continue to be monitored, and the patient continues to see the gastroenterologist.
ConclusionsGastrointestinal side effects are very common when taking antidepressant treatment, and in most cases they do not usually represent a serious problem.
However, it is described in the scientific literature that in some cases, acute pancreatitis secondary to some drugs, including Venlafaxine, can occur (4). In order to detect it, it is necessary to perform a blood test and sometimes also other complementary tests.
For its treatment, the fundamental thing is to withdraw the causing drug, trying to find other alternatives, and carry out a control to monitor possible complications
Disclosure of InterestNone Declared
361 WDR5 represents a therapeutically exploitable target for cancer stem cells in glioblastoma
- Part of
- Christopher Hubert, Kelly Mitchell, Samuel Sprowls, Sajina Shakya, Sonali Arora, Daniel J. Silver, Christopher M. Goins, Lisa Wallace, Gustavo Roversi, Rachel Schafer, Kristen Kay, Tyler E. Miller, Adam Lauko, John Bassett, Anjali Kashyap, J. D’Amato Kass, Erin E. Mulkearns-Hubert, Sadie Johnson, Joseph Alvarado, Jeremy N. Rich, Patrick J. Paddison, Anoop P. Patel, Shaun R. Stauffer, Christopher G. Hubert, Justin D. Lathia
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- Journal:
- Journal of Clinical and Translational Science / Volume 7 / Issue s1 / April 2023
- Published online by Cambridge University Press:
- 24 April 2023, p. 107
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OBJECTIVES/GOALS: Glioblastomas (GBMs) are heterogeneous, treatment-resistant tumors that are driven by populations of cancer stem cells (CSCs). In this study, we perform an epigenetic-focused functional genomics screen in GBM organoids and identify WDR5 as an essential epigenetic regulator in the SOX2-enriched, therapy resistant cancer stem cell niche. METHODS/STUDY POPULATION: Despite their importance for tumor growth, few molecular mechanisms critical for CSC population maintenance have been exploited for therapeutic development. We developed a spatially resolved loss-of-function screen in GBM patient-derived organoids to identify essential epigenetic regulators in the SOX2-enriched, therapy resistant niche. Our niche-specific screens identified WDR5, an H3K4 histone methyltransferase responsible for activating specific gene expression, as indispensable for GBM CSC growth and survival. RESULTS/ANTICIPATED RESULTS: In GBM CSC models, WDR5 inhibitors blocked WRAD complex assembly and reduced H3K4 trimethylation and expression of genes involved in CSC-relevant oncogenic pathways. H3K4me3 peaks lost with WDR5 inhibitor treatment occurred disproportionally on POU transcription factor motifs, required for stem cell maintenance and including the POU5F1(OCT4)::SOX2 motif. We incorporated a SOX2/OCT4 motif driven GFP reporter system into our CSC cell models and found that WDR5 inhibitor treatment resulted in dose-dependent silencing of stem cell reporter activity. Further, WDR5 inhibitor treatment altered the stem cell state, disrupting CSC in vitro growth and self-renewal as well as in vivo tumor growth. DISCUSSION/SIGNIFICANCE: Our results unveiled the role of WDR5 in maintaining the CSC state in GBM and provide a rationale for therapeutic development of WDR5 inhibitors for GBM and other advanced cancers. This conceptual and experimental framework can be applied to many cancers, and can unmask unique microenvironmental biology and rationally designed combination therapies.
The Concept of Legitimacy
- N. P. Adams
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- Canadian Journal of Philosophy / Volume 52 / Issue 4 / May 2022
- Published online by Cambridge University Press:
- 07 October 2022, pp. 381-395
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I argue that legitimacy discourses serve a gatekeeping function. They give practitioners telic standards for riding herd on social practices, ensuring that minimally acceptable versions of the practice are implemented. Such a function is a necessary part of implementing formalized social practices, especially including law. This gatekeeping account shows that political philosophers have misunderstood legitimacy. It is not secondary to justice and only necessary because we cannot agree about justice; instead, it is a necessary feature of actual human social practices, which must be implemented via practitioners’ discretion in changing contexts.
Goldhillite, Cu5Zn(AsO4)2(OH)6⋅H2O, a new mineral species, and redefinition of philipsburgite, Cu5Zn[(AsO4)(PO4)](OH)6⋅H2O, as an As–P ordered species
- Rezeda M. Ismagilova, Branko Rieck, Anthony R. Kampf, Gerald Giester, Elena S. Zhitova, Christian L. Lengauer, Sergey V. Krivovichev, Andrey A. Zolotarev, Justyna Ciesielczuk, Julia A. Mikhailova, Dmitry I. Belakovsky, Vladimir N. Bocharov, Vladimir V. Shilovskikh, Natalia S. Vlasenko, Barbara P. Nash, Paul M. Adams
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- Journal:
- Mineralogical Magazine / Volume 86 / Issue 3 / June 2022
- Published online by Cambridge University Press:
- 13 May 2022, pp. 436-446
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Philipsburgite has been redefined as the intermediate member of the goldhillite–philipsburgite–kipushite isomorphous series with the ideal formula Cu5Zn[(AsO4)(PO4)](OH)6⋅H2O due to the site-selective As–P substitution. The new mineral goldhillite, ideally Cu5Zn(AsO4)2(OH)6⋅H2O [or Cu5Zn(AsO4)(AsO4)(OH)6⋅H2O], is the arsenate end-member of this series. Goldhillite occurs on fracture surfaces in a rock comprised mostly of quartz with iron hydroxides in association with mixite, cornwallite and conichalcite. Goldhillite forms transparent, bright emerald-green, tabular crystals with vitreous lustre, flattened on {100}, up to 1 mm across and in rosettes up to 1.5 mm. The mineral is brittle with uneven fracture and perfect cleavage on {100}; the Mohs hardness is 3.5. The calculated density for the holotype is 4.199 g cm–3. The Raman spectrum is consistent with the presence of H2O-molecules, OH-groups, AsO4 tetrahedra and traces of PO4. Electron microprobe analyses of goldhillite (H2O content based on the crystal structure) provided: CuO 48.91, ZnO 13.18, As2O5 26.06, P2O5 3.25, H2O 8.97, total 100.37 wt.%. The empirical formula for goldhillite based on O = 15 apfu is (Cu4.69Zn1.23)Σ5.92(As0.86P0.18O4)2(OH)5.61⋅H2O. The crystal structures of goldhillite and philipsburgite were determined using single-crystal X-ray diffraction data and refined to R1 = 0.054 (for 2365 I > 2σI reflections) and 0.052 (for 2308 I > 2σI reflections), respectively. Goldhillite is monoclinic, P21/c, a = 12.3573(5), b = 9.2325(3), c = 10.7163(4) Å, β = 97.346(4)°, V = 1212.59(8) Å3 and Z = 4. Philipsburgite is monoclinic, P21/c, a = 12.3095(9), b = 9.2276(3), c = 10.7195(3) Å, β = 97.137(7)°, V = 1208.16(10) Å3 and Z = 4. The strongest lines of the powder X-ray diffraction pattern of goldhillite [d, Å (I, %)(hkl)] are: 4.09 (28)(300), 3.41 (23)(12$\bar{2}$, 221, 311), 2.57 (100)(132, 11$\bar{4}$, 20$\bar{4}$), 2.17 (18)(42$\bar{3}$, 332), 1.95 (22)(432) and 1.54 (20)(13$\bar{6}$, 060). Goldhillite is named after its type locality, the Gold Hill mine, Tooele County, Utah, USA.
The ASKAP Variables and Slow Transients (VAST) Pilot Survey
- Part of
- Tara Murphy, David L. Kaplan, Adam J. Stewart, Andrew O’Brien, Emil Lenc, Sergio Pintaldi, Joshua Pritchard, Dougal Dobie, Archibald Fox, James K. Leung, Tao An, Martin E. Bell, Jess W. Broderick, Shami Chatterjee, Shi Dai, Daniele d’Antonio, Gerry Doyle, B. M. Gaensler, George Heald, Assaf Horesh, Megan L. Jones, David McConnell, Vanessa A. Moss, Wasim Raja, Gavin Ramsay, Stuart Ryder, Elaine M. Sadler, Gregory R. Sivakoff, Yuanming Wang, Ziteng Wang, Michael S. Wheatland, Matthew Whiting, James R. Allison, C. S. Anderson, Lewis Ball, K. Bannister, D. C.-J. Bock, R. Bolton, J. D. Bunton, R. Chekkala, A. P Chippendale, F. R. Cooray, N. Gupta, D. B. Hayman, K. Jeganathan, B. Koribalski, K. Lee-Waddell, Elizabeth K. Mahony, J. Marvil, N. M. McClure-Griffiths, P. Mirtschin, A. Ng, S. Pearce, C. Phillips, M. A. Voronkov
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- Journal:
- Publications of the Astronomical Society of Australia / Volume 38 / 2021
- Published online by Cambridge University Press:
- 12 October 2021, e054
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The Variables and Slow Transients Survey (VAST) on the Australian Square Kilometre Array Pathfinder (ASKAP) is designed to detect highly variable and transient radio sources on timescales from 5 s to $\sim\!5$ yr. In this paper, we present the survey description, observation strategy and initial results from the VAST Phase I Pilot Survey. This pilot survey consists of $\sim\!162$ h of observations conducted at a central frequency of 888 MHz between 2019 August and 2020 August, with a typical rms sensitivity of $0.24\ \mathrm{mJy\ beam}^{-1}$ and angular resolution of $12-20$ arcseconds. There are 113 fields, each of which was observed for 12 min integration time, with between 5 and 13 repeats, with cadences between 1 day and 8 months. The total area of the pilot survey footprint is 5 131 square degrees, covering six distinct regions of the sky. An initial search of two of these regions, totalling 1 646 square degrees, revealed 28 highly variable and/or transient sources. Seven of these are known pulsars, including the millisecond pulsar J2039–5617. Another seven are stars, four of which have no previously reported radio detection (SCR J0533–4257, LEHPM 2-783, UCAC3 89–412162 and 2MASS J22414436–6119311). Of the remaining 14 sources, two are active galactic nuclei, six are associated with galaxies and the other six have no multi-wavelength counterparts and are yet to be identified.
Cardiac echocardiogram findings of severe acute respiratory syndrome coronavirus-2-associated multi-system inflammatory syndrome in children – CORRIGENDUM
- Ashraf S. Harahsheh, Anita Krishnan, Roberta L. DeBiasi, Laura J. Olivieri, Christopher Spurney, Mary T. Donofrio, Russell R. Cross, Matthew P. Sharron, Lowell H. Frank, Charles I. Berul, Adam Christopher, Niti Dham, Hemalatha Srinivasalu, Tova Ronis, Karen L. Smith, Jaclyn N. Kline, Kavita Parikh, David Wessel, James E. Bost, Sarah Litt, Ashley Austin, Jing Zhang, Craig A. Sable
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- Journal:
- Cardiology in the Young / Volume 32 / Issue 5 / May 2022
- Published online by Cambridge University Press:
- 31 August 2021, p. 727
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Cardiac echocardiogram findings of severe acute respiratory syndrome coronavirus-2-associated multi-system inflammatory syndrome in children
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- Ashraf S. Harahsheh, Anita Krishnan, Roberta L. DeBiasi, Laura J. Olivieri, Christopher Spurney, Mary T. Donofrio, Russell R. Cross, Matthew P. Sharron, Lowell H. Frank, Charles I. Berul, Adam Christopher, Niti Dham, Hemalatha Srinivasalu, Tova Ronis, Karen L. Smith, Jaclyn N. Kline, Kavita Parikh, David Wessel, James E. Bost, Sarah Litt, Ashley Austin, Jing Zhang, Craig A. Sable
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- Cardiology in the Young / Volume 32 / Issue 5 / May 2022
- Published online by Cambridge University Press:
- 05 August 2021, pp. 718-726
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Background:
A novel paediatric disease, multi-system inflammatory syndrome in children, has emerged during the 2019 coronavirus disease pandemic.
Objectives:To describe the short-term evolution of cardiac complications and associated risk factors in patients with multi-system inflammatory syndrome in children.
Methods:Retrospective single-centre study of confirmed multi-system inflammatory syndrome in children treated from 29 March, 2020 to 1 September, 2020. Cardiac complications during the acute phase were defined as decreased systolic function, coronary artery abnormalities, pericardial effusion, or mitral and/or tricuspid valve regurgitation. Patients with or without cardiac complications were compared with chi-square, Fisher’s exact, and Wilcoxon rank sum.
Results:Thirty-nine children with median (interquartile range) age 7.8 (3.6–12.7) years were included. Nineteen (49%) patients developed cardiac complications including systolic dysfunction (33%), valvular regurgitation (31%), coronary artery abnormalities (18%), and pericardial effusion (5%). At the time of the most recent follow-up, at a median (interquartile range) of 49 (26–61) days, cardiac complications resolved in 16/19 (84%) patients. Two patients had persistent mild systolic dysfunction and one patient had persistent coronary artery abnormality. Children with cardiac complications were more likely to have higher N-terminal B-type natriuretic peptide (p = 0.01), higher white blood cell count (p = 0.01), higher neutrophil count (p = 0.02), severe lymphopenia (p = 0.05), use of milrinone (p = 0.03), and intensive care requirement (p = 0.04).
Conclusion:Patients with multi-system inflammatory syndrome in children had a high rate of cardiac complications in the acute phase, with associated inflammatory markers. Although cardiac complications resolved in 84% of patients, further long-term studies are needed to assess if the cardiac abnormalities (transient or persistent) are associated with major cardiac events.
The Rapid ASKAP Continuum Survey I: Design and first results
- Part of
- D. McConnell, C. L. Hale, E. Lenc, J. K. Banfield, George Heald, A. W. Hotan, James K. Leung, Vanessa A. Moss, Tara Murphy, Andrew O’Brien, Joshua Pritchard, Wasim Raja, Elaine M. Sadler, Adam Stewart, Alec J. M. Thomson, M. Whiting, James R. Allison, S. W. Amy, C. Anderson, Lewis Ball, Keith W. Bannister, Martin Bell, Douglas C.-J. Bock, Russ Bolton, J. D. Bunton, A. P. Chippendale, J. D. Collier, F. R. Cooray, T. J. Cornwell, P. J. Diamond, P. G. Edwards, N. Gupta, Douglas B. Hayman, Ian Heywood, C. A. Jackson, Bärbel S. Koribalski, Karen Lee-Waddell, N. M. McClure-Griffiths, Alan Ng, Ray P. Norris, Chris Phillips, John E. Reynolds, Daniel N. Roxby, Antony E. T. Schinckel, Matt Shields, Chenoa Tremblay, A. Tzioumis, M. A. Voronkov, Tobias Westmeier
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- Journal:
- Publications of the Astronomical Society of Australia / Volume 37 / 2020
- Published online by Cambridge University Press:
- 30 November 2020, e048
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The Rapid ASKAP Continuum Survey (RACS) is the first large-area survey to be conducted with the full 36-antenna Australian Square Kilometre Array Pathfinder (ASKAP) telescope. RACS will provide a shallow model of the ASKAP sky that will aid the calibration of future deep ASKAP surveys. RACS will cover the whole sky visible from the ASKAP site in Western Australia and will cover the full ASKAP band of 700–1800 MHz. The RACS images are generally deeper than the existing NRAO VLA Sky Survey and Sydney University Molonglo Sky Survey radio surveys and have better spatial resolution. All RACS survey products will be public, including radio images (with $\sim$ 15 arcsec resolution) and catalogues of about three million source components with spectral index and polarisation information. In this paper, we present a description of the RACS survey and the first data release of 903 images covering the sky south of declination $+41^\circ$ made over a 288-MHz band centred at 887.5 MHz.
The IntCal20 Northern Hemisphere Radiocarbon Age Calibration Curve (0–55 cal kBP)
- Part of
- Paula J Reimer, William E N Austin, Edouard Bard, Alex Bayliss, Paul G Blackwell, Christopher Bronk Ramsey, Martin Butzin, Hai Cheng, R Lawrence Edwards, Michael Friedrich, Pieter M Grootes, Thomas P Guilderson, Irka Hajdas, Timothy J Heaton, Alan G Hogg, Konrad A Hughen, Bernd Kromer, Sturt W Manning, Raimund Muscheler, Jonathan G Palmer, Charlotte Pearson, Johannes van der Plicht, Ron W Reimer, David A Richards, E Marian Scott, John R Southon, Christian S M Turney, Lukas Wacker, Florian Adolphi, Ulf Büntgen, Manuela Capano, Simon M Fahrni, Alexandra Fogtmann-Schulz, Ronny Friedrich, Peter Köhler, Sabrina Kudsk, Fusa Miyake, Jesper Olsen, Frederick Reinig, Minoru Sakamoto, Adam Sookdeo, Sahra Talamo
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- Journal:
- Radiocarbon / Volume 62 / Issue 4 / August 2020
- Published online by Cambridge University Press:
- 12 August 2020, pp. 725-757
- Print publication:
- August 2020
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Radiocarbon (14C) ages cannot provide absolutely dated chronologies for archaeological or paleoenvironmental studies directly but must be converted to calendar age equivalents using a calibration curve compensating for fluctuations in atmospheric 14C concentration. Although calibration curves are constructed from independently dated archives, they invariably require revision as new data become available and our understanding of the Earth system improves. In this volume the international 14C calibration curves for both the Northern and Southern Hemispheres, as well as for the ocean surface layer, have been updated to include a wealth of new data and extended to 55,000 cal BP. Based on tree rings, IntCal20 now extends as a fully atmospheric record to ca. 13,900 cal BP. For the older part of the timescale, IntCal20 comprises statistically integrated evidence from floating tree-ring chronologies, lacustrine and marine sediments, speleothems, and corals. We utilized improved evaluation of the timescales and location variable 14C offsets from the atmosphere (reservoir age, dead carbon fraction) for each dataset. New statistical methods have refined the structure of the calibration curves while maintaining a robust treatment of uncertainties in the 14C ages, the calendar ages and other corrections. The inclusion of modeled marine reservoir ages derived from a three-dimensional ocean circulation model has allowed us to apply more appropriate reservoir corrections to the marine 14C data rather than the previous use of constant regional offsets from the atmosphere. Here we provide an overview of the new and revised datasets and the associated methods used for the construction of the IntCal20 curve and explore potential regional offsets for tree-ring data. We discuss the main differences with respect to the previous calibration curve, IntCal13, and some of the implications for archaeology and geosciences ranging from the recent past to the time of the extinction of the Neanderthals.
The MeerKAT telescope as a pulsar facility: System verification and early science results from MeerTime
- M. Bailes, A. Jameson, F. Abbate, E. D. Barr, N. D. R. Bhat, L. Bondonneau, M. Burgay, S. J. Buchner, F. Camilo, D. J. Champion, I. Cognard, P. B. Demorest, P. C. C. Freire, T. Gautam, M. Geyer, J.-M. Griessmeier, L. Guillemot, H. Hu, F. Jankowski, S. Johnston, A. Karastergiou, R. Karuppusamy, D. Kaur, M. J. Keith, M. Kramer, J. van Leeuwen, M. E. Lower, Y. Maan, M. A. McLaughlin, B. W. Meyers, S. Osłowski, L. S. Oswald, A. Parthasarathy, T. Pennucci, B. Posselt, A. Possenti, S. M. Ransom, D. J. Reardon, A. Ridolfi, C. T. G. Schollar, M. Serylak, G. Shaifullah, M. Shamohammadi, R. M. Shannon, C. Sobey, X. Song, R. Spiewak, I. H. Stairs, B. W. Stappers, W. van Straten, A. Szary, G. Theureau, V. Venkatraman Krishnan, P. Weltevrede, N. Wex, T. D. Abbott, G. B. Adams, J. P. Burger, R. R. G. Gamatham, M. Gouws, D. M. Horn, B. Hugo, A. F. Joubert, J. R. Manley, K. McAlpine, S. S. Passmoor, A. Peens-Hough, Z. R Ramudzuli, A. Rust, S. Salie, L. C. Schwardt, R. Siebrits, G. Van Tonder, V. Van Tonder, M. G. Welz
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- Journal:
- Publications of the Astronomical Society of Australia / Volume 37 / 2020
- Published online by Cambridge University Press:
- 15 July 2020, e028
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We describe system verification tests and early science results from the pulsar processor (PTUSE) developed for the newly commissioned 64-dish SARAO MeerKAT radio telescope in South Africa. MeerKAT is a high-gain ( ${\sim}2.8\,\mbox{K Jy}^{-1}$ ) low-system temperature ( ${\sim}18\,\mbox{K at }20\,\mbox{cm}$ ) radio array that currently operates at 580–1 670 MHz and can produce tied-array beams suitable for pulsar observations. This paper presents results from the MeerTime Large Survey Project and commissioning tests with PTUSE. Highlights include observations of the double pulsar $\mbox{J}0737{-}3039\mbox{A}$ , pulse profiles from 34 millisecond pulsars (MSPs) from a single 2.5-h observation of the Globular cluster Terzan 5, the rotation measure of Ter5O, a 420-sigma giant pulse from the Large Magellanic Cloud pulsar PSR $\mbox{J}0540{-}6919$ , and nulling identified in the slow pulsar PSR J0633–2015. One of the key design specifications for MeerKAT was absolute timing errors of less than 5 ns using their novel precise time system. Our timing of two bright MSPs confirm that MeerKAT delivers exceptional timing. PSR $\mbox{J}2241{-}5236$ exhibits a jitter limit of $<4\,\mbox{ns h}^{-1}$ whilst timing of PSR $\mbox{J}1909{-}3744$ over almost 11 months yields an rms residual of 66 ns with only 4 min integrations. Our results confirm that the MeerKAT is an exceptional pulsar telescope. The array can be split into four separate sub-arrays to time over 1 000 pulsars per day and the future deployment of S-band (1 750–3 500 MHz) receivers will further enhance its capabilities.