To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Dr Daniel Gibbs is one of 50 million people worldwide with an Alzheimer's disease diagnosis. Unlike most patients with Alzheimer's, however, Dr Gibbs worked as a neurologist for twenty-five years, caring for patients with the very disease now affecting him. Also unusual is that Dr Gibbs had begun to suspect he had Alzheimer's several years before any official diagnosis could be made. Forewarned by genetic testing showing he carried alleles that increased the risk of developing the disease, he noticed symptoms of mild cognitive impairment long before any tests would have alerted him. In this highly personal account, Dr Gibbs documents the effect his diagnosis has had on his life and explains his advocacy for improving early recognition of Alzheimer's. Weaving clinical knowledge from decades caring for dementia patients with his personal experience of the disease, this is an optimistic tale of one man's journey with early-stage Alzheimer's disease.
With human influences driving populations of apex predators into decline, more information is required on how factors affect species at national and global scales. However, camera-trap studies are seldom executed at a broad spatial scale. We demonstrate how uniting fine-scale studies and utilizing camera-trap data of non-target species is an effective approach for broadscale assessments through a case study of the brown hyaena Parahyaena brunnea. We collated camera-trap data from 25 protected and unprotected sites across South Africa into the largest detection/non-detection dataset collected on the brown hyaena, and investigated the influence of biological and anthropogenic factors on brown hyaena occupancy. Spatial autocorrelation had a significant effect on the data, and was corrected using a Bayesian Gibbs sampler. We show that brown hyaena occupancy is driven by specific co-occurring apex predator species and human disturbance. The relative abundance of spotted hyaenas Crocuta crocuta and people on foot had a negative effect on brown hyaena occupancy, whereas the relative abundance of leopards Panthera pardus and vehicles had a positive influence. We estimated that brown hyaenas occur across 66% of the surveyed camera-trap station sites. Occupancy varied geographically, with lower estimates in eastern and southern South Africa. Our findings suggest that brown hyaena conservation is dependent upon a multi-species approach focussed on implementing conservation policies that better facilitate coexistence between people and hyaenas. We also validate the conservation value of pooling fine-scale datasets and utilizing bycatch data to examine species trends at broad spatial scales.
Neuroanthropology is an interdisciplinary approach to studying human variation that integrates brain and cognitive sciences with anthropology and uses theoretically and biologically informed ethnography to examine specific problems at the intersection of brain and culture. This chapter shows how, for instance, the theoretical construct, habitus, can be integrated with accounts of human development and brain enculturation to better understand the internalization of social structures, including how socialization produces both diversity as well as shared outcomes. We also show how ideas from computational neuroscience, such as work on prediction errors and the free energy principle, can augment the understanding of cultural consensus and consonance, or how culture is at once shared and individual. The overarching goal of neuroanthropology is to bolster biocultural exploration of individual enculturation and ground social theory in a more accurate account of individual neurobiology in order to encourage a broader, multidisciplinary study of human cultural variation.
Antarctica's ice shelves modulate the grounded ice flow, and weakening of ice shelves due to climate forcing will decrease their ‘buttressing’ effect, causing a response in the grounded ice. While the processes governing ice-shelf weakening are complex, uncertainties in the response of the grounded ice sheet are also difficult to assess. The Antarctic BUttressing Model Intercomparison Project (ABUMIP) compares ice-sheet model responses to decrease in buttressing by investigating the ‘end-member’ scenario of total and sustained loss of ice shelves. Although unrealistic, this scenario enables gauging the sensitivity of an ensemble of 15 ice-sheet models to a total loss of buttressing, hence exhibiting the full potential of marine ice-sheet instability. All models predict that this scenario leads to multi-metre (1–12 m) sea-level rise over 500 years from present day. West Antarctic ice sheet collapse alone leads to a 1.91–5.08 m sea-level rise due to the marine ice-sheet instability. Mass loss rates are a strong function of the sliding/friction law, with plastic laws cause a further destabilization of the Aurora and Wilkes Subglacial Basins, East Antarctica. Improvements to marine ice-sheet models have greatly reduced variability between modelled ice-sheet responses to extreme ice-shelf loss, e.g. compared to the SeaRISE assessments.
Although pharmacologic therapy remains the mainstay of treatment for most types of epilepsy, today the use of dietary therapy, most notably the ketogenic diet (KD), has become increasingly recognized as helpful, especially in those patients whose seizures are resistant to traditional anti-seizure medications. The history of using dietary manipulation for seizures dates back to the time of The Bible . There are descriptions of Jesus curing ‘possessed’ patients with prayer and fasting [2,3].
This chapter discusses the relevance of addiction to the law in the United States. Current law pertains almost solely to substance addictions, as there is no legal status pertaining to most behavioral addictions. Particular emphasis is placed on the law’s impact on the provision of care and research of addiction. The conflicting legal concerns for confidentiality of treatment and research, on the one hand, and apprehension of addicts who break the law, on the other hand, are examined.
We investigated the impact of regionally imposed social and healthcare restrictions due to coronavirus disease 2019 (COVID-19) to the time metrics in the management of acute ischemic stroke patients admitted at the regional stroke referral site for Central South Ontario, Canada.
We compared relevant time metrics between patients with acute ischemic stroke receiving intravenous tissue plasminogen activator (tPA) and/or endovascular thrombectomy (EVT) before and after the declared restrictions and state of emergency imposed in our region (March 17, 2020).
We identified a significant increase in the median door-to-CT times for patients receiving intravenous tPA (19 min, interquartile range (IQR): 14–27 min vs. 13 min, IQR: 9–17 min, p = 0.008) and/or EVT (20 min, IQR: 15–33 min vs. 11 min, IQR: 5–20 min, p = 0.035) after the start of social and healthcare restrictions in our region compared to the previous 12 months. For patients receiving intravenous tPA treatment, we also found a significant increase (p = 0.005) in the median door-to-needle time (61 min, IQR: 46–72 min vs. 37 min, IQR: 30–50 min). No delays in the time from symptom onset to hospital presentation were uncovered for patients receiving tPA and/or endovascular reperfusion treatments in the first 1.5 months after the establishment of regional and institutional restrictions due to the COVID-19 pandemic.
We detected an increase in our institutional time to treatment metrics for acute ischemic stroke patients receiving tPA and/or endovascular reperfusion therapies, related to delays from hospital presentation to the acquisition of cranial CT imaging for both tPA- and EVT-treated patients, and an added delay to treatment with tPA.
Life course research embraces the complexity of health and disease development, tackling the extensive interactions between genetics and environment. This interdisciplinary blueprint, or theoretical framework, offers a structure for research ideas and specifies relationships between related factors. Traditionally, methodological approaches attempt to reduce the complexity of these dynamic interactions and decompose health into component parts, ignoring the complex reciprocal interaction of factors that shape health over time. New methods that match the epistemological foundation of the life course framework are needed to fully explore adaptive, multilevel, and reciprocal interactions between individuals and their environment. The focus of this article is to (1) delineate the differences between lifespan and life course research, (2) articulate the importance of complex systems science as a methodological framework in the life course research toolbox to guide our research questions, (3) raise key questions that can be asked within the clinical and translational science domain utilizing this framework, and (4) provide recommendations for life course research implementation, charting the way forward. Recent advances in computational analytics, computer science, and data collection could be used to approximate, measure, and analyze the intertwining and dynamic nature of genetic and environmental factors involved in health development.
Off-target paraquat movement to rice has become a major problem in recent years for rice producers in the midsouthern United States. Nitrogen (N) fertilizer is applied to rice in greater quantity and frequency than all other nutrients to optimize rice yield. Two separate field studies were conducted from 2015 to 2018 in Stoneville, MS, to assess whether starter N fertilizer can aid rice recovery from exposure to a sub-lethal concentration of paraquat and to evaluate rice response to different N fertilizer management strategies following exposure to a sub-lethal concentration of paraquat. In both studies, paraquat treatments consisted of paraquat at 0 and 84 g ai ha–1 applied to rice in the two- to three-leaf (EPOST) growth stage. In the starter fertilizer study, N fertilizer at 24 kg ha–1 as ammonium sulfate (AMS) was applied to rice at spiking- to one-leaf (VEPOST), two- to three-leaf (EPOST), or three- to four-leaf (MPOST) growth stages before and after paraquat treatment. In the N fertilizer timing study, N fertilizer at 168 kg N ha–1 was applied in a single four-leaf to one-tiller (LPOST) application or two-, three-, and two four-way split applications. Despite starter N fertilizer applications, paraquat injured rice ≥41%, reduced height 57%, reduced dry weight prior to flooding 77%, delayed maturity 10 d, reduced dry weight at maturity 33%, and reduced rough rice yield 35% in the starter fertilizer study. Similarly, in the N fertilizer timing study, paraquat injured rice ≥45%, reduced height 14%, delayed maturity 10 d, reduced dry weight at maturity 44%, and reduced rough rice yield 50% for all N fertilizer management strategies. Both studies indicate that severe complications in growth and development can occur from rice exposure to a sub-lethal concentration of paraquat. In both studies, manipulation of N fertilizer management did not facilitate rice recovery from early-season exposure to paraquat.
Impairments in social cognition contribute significantly to disability in schizophrenia patients (SzP). Perception of facial expressions is critical for social cognition. Intact perception requires an individual to visually scan a complex dynamic social scene for transiently moving facial expressions that may be relevant for understanding the scene. The relationship of visual scanning for these facial expressions and social cognition remains unknown.
In 39 SzP and 27 healthy controls (HC), we used eye-tracking to examine the relationship between performance on The Awareness of Social Inference Test (TASIT), which tests social cognition using naturalistic video clips of social situations, and visual scanning, measuring each individual's relative to the mean of HC. We then examined the relationship of visual scanning to the specific visual features (motion, contrast, luminance, faces) within the video clips.
TASIT performance was significantly impaired in SzP for trials involving sarcasm (p < 10−5). Visual scanning was significantly more variable in SzP than HC (p < 10−6), and predicted TASIT performance in HC (p = 0.02) but not SzP (p = 0.91), differing significantly between groups (p = 0.04). During the visual scanning, SzP were less likely to be viewing faces (p = 0.0001) and less likely to saccade to facial motion in peripheral vision (p = 0.008).
SzP show highly significant deficits in the use of visual scanning of naturalistic social scenes to inform social cognition. Alterations in visual scanning patterns may originate from impaired processing of facial motion within peripheral vision. Overall, these results highlight the utility of naturalistic stimuli in the study of social cognition deficits in schizophrenia.
Scattering phenomena between charged particles and highly excited Rydberg atoms are of critical importance in many processes in plasma physics and astrophysics. While a Maxwell–Boltzmann (MB) energy distribution for the charged particles is often assumed for calculations of collisional rate coefficients, in this contribution we relax this assumption and use two different energy distributions, a bimodal MB distribution and a
-distribution. Both variants share a high-energy tails occurring with higher probability than the corresponding MB distribution. The high-energy tail may significantly affect rate coefficients for various processes. We focus the analysis to specific situations by showing the dependence of the rate coefficients on the principal quantum number of hydrogen atoms in
-changing collisions with electrons in the excitation and ionization channels and in a temperature range relevant to the divertor region of a tokamak device. We finally discuss the implications for diagnostics of laboratory plasmas.
Major depressive disorder (MDD) is associated with increased allostatic load (AL; a measure of physiological costs of repeated/chronic stress-responding) and metabolic dysregulation (MetD; a measure of metabolic health and precursor to many medical illnesses). Though AL and MetD are associated with poor somatic health outcomes, little is known regarding their relationship with antidepressant-treatment outcomes.
We determined pre-treatment AL and MetD in 67 healthy controls and 34 unmedicated, medically healthy MDD subjects. Following this, MDD subjects completed 8-weeks of open-label selective serotonin reuptake inhibitor (SSRI) antidepressant treatment and were categorized as ‘Responders’ (⩾50% improvement in depression severity ratings) or ‘Non-responders’ (<50% improvement). Logistic and linear regressions were performed to determine if pre-treatment AL or MetD scores predicted SSRI-response. Secondary analyses examined cross-sectional differences between MDD and control groups.
Pre-treatment AL and MetD scores significantly predicted continuous antidepressant response (i.e. absolute decreases in depression severity ratings) (p = 0.012 and 0.014, respectively), as well as post-treatment status as a Responder or Non-responder (p = 0.022 and 0.040, respectively), such that higher pre-treatment AL and MetD were associated with poorer SSRI-treatment outcomes. Pre-treatment AL and MetD of Responders were similar to Controls, while those of Non-responders were significantly higher than both Responders (p = 0.025 and 0.033, respectively) and Controls (p = 0.039 and 0.001, respectively).
These preliminary findings suggest that indices of metabolic and hypothalamic-pituitary-adrenal-axis dysregulation are associated with poorer SSRI-treatment response. To our knowledge, this is the first study to demonstrate that these markers of medical disease risk also predict poorer antidepressant outcomes.
This chapter focuses on advancements in the understanding of personality pathology gained from structural and functional neuroimaging studies. It draws from the literature on the most widely researched personality disorders including schizotypal, borderline, and antisocial personality disorder. Prominent findings in schizotypal personality disorder include abnormalities in temporal and frontal lobe volumes, decreased structural connectivity of temporal lobe regions, and inefficient recruitment of brain areas during task performance. In borderline personality disorder, neuroimaging findings are characterized by aberrant volume and activity of limbic and prefrontal brain areas that suggest diminished top-down control of affective responsivity. Studies in antisocial personality disorder reveal reduced volume in prefrontal and temporal lobe structures, white matter structure compromise, and altered brain network functional connectivity. Significant challenges in studying this complex population and limitations of current methodology are discussed. Suggestions for future directions of research in this field are provided.
This rejoinder uses the neuroimaging literature on affect regulation to exemplify how integration of complementary methods suggested by the commentaries could advance neurobiological understanding of personality disorders. It illustrates progressive insights gained from incorporating multiple sources of evidence including neuroimaging, genetics, and behavioral data associated with affect regulation. It also demonstrates the use of brain pattern activation analysis in addition to studying individual regions of interest to better understand the complex relationships between biological genotype, brain activity, and behavioral phenotype. The ways in which neuroimaging can serve as an endophenotype to bridge the gap between genes and distant phenotypes are highlighted.
Maternal undernutrition decreases sperm production in male offspring, possibly through insulin-like growth factor (IGF-I). To test this hypothesis, we fed pregnant Wistar rats ad libitum with a standard diet (CONTROL) or fed 50% of CONTROL intake, either throughout pregnancy (UNP), lactation (UNL, or both (UNPL). After weaning, male offspring (n = 10 per treatment) were fed a standard diet until postnatal day 160, when testes process for histological and molecular analyses. IGF-I immunostaining area and intensity in the testis were greater (P = 0.003) in the UNPL group compared to CONTROL, but lower in the UNP group (P < 0.0001). Levels of IGF-I receptor transcript were lower in the UNPL and UNL groups, compared to CONTROL. There were more Ki-67-positive germ and Sertoli cells, in all underfed groups than in CONTROL. Compared to CONTROL, frequency of spermatogenic cycle stage VII was lower in all underfed groups, and seminiferous tubule diameter was smaller in UNP and UNPL. Plasma FSH concentrations were greater in UNP male offspring compared to all groups (P = 0.05), whereas inhibin B concentrations were greater in UNP (P = 0.01) and UNL (P = 0.003) than in CONTROL or UNPL. Thus, prenatal undernutrition leads to a decrease in testicular IGF-I levels, whereas of pre- and postnatal undernutrition increased testicular IGF-I levels and decreased amounts of IGF-I receptor mRNA in adult offspring. We conclude that maternal undernutrition during pregnancy and lactation leads to long-lasting effects on adult male offspring testicular morphology, spermatogenesis, and IGF-I testicular system.