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Mobile systems, whose components communicate and change their structure, now pervade the informational world and the wider world of which it is a part. The science of mobile systems is as yet immature, however. This book presents the pi-calculus, a theory of mobile systems. The pi-calculus provides a conceptual framework for understanding mobility, and mathematical tools for expressing systems and reasoning about their behaviours. The book serves both as a reference for the theory and as an extended demonstration of how to use pi-calculus to describe systems and analyse their properties. It covers the basic theory of pi-calculus, typed pi-calculi, higher-order processes, the relationship between pi-calculus and lambda-calculus, and applications of pi-calculus to object-oriented design and programming. The book is written at the graduate level, assuming no prior acquaintance with the subject, and is intended for computer scientists interested in mobile systems.
A paleotemperature reconstruction inferred from subfossil chironomid (non-biting midge) assemblages in a 13-meter, 14,500-yr lake sediment record from a montane forest in the Pacific Northwest is compared to existing quantitative temperature reconstructions from the Pacific Northwest. With updated temperatures, a regional training set was used to develop a midge-based mean July air temperature (MJAT) inference model (r2jack = 0.71, root mean square error of prediction = 1.09°C). The average inferred MJAT varied between 9.4°C and 13.2°C. During the late-glacial period, MJAT ranged between 9.4°C and 10.8°C, and the lowest MJAT (9.4°C) is inferred at ca. 12.7 ka during the Younger Dryas. The transition into the Early Holocene was marked by an increase from 11°C at 11 ka to 12°C at 9.2 ka. Following deposition of the Mazama tephra, chironomid concentration decreased rapidly, and MJAT rose to 12.3°C at ca. 7.6 ka. This change in chironomid assemblage may be due to the direct effects of the tephra on the surface energy balance. The reconstructed temperature did not track decreasing Holocene summer insolation but instead revealed Late Holocene warming, which is similar to a chironomid reconstruction in the eastern Sierra Nevada and a sea-surface temperature reconstruction from northern California.
Direct physical evidence for violent interpersonal conflict is seen only sporadically in the archaeological record for prehistoric Britain. Human remains from Charterhouse Warren, south-west England, therefore present a unique opportunity for the study of mass violence in the Early Bronze Age. At least 37 men, women and children were killed and butchered, their disarticulated remains thrown into a 15m-deep natural shaft in what is, most plausibly, interpreted as a single event. The authors examine the physical remains and debate the societal tensions that could motivate a level and scale of violence that is unprecedented in British prehistory.
The angular correlation is a method for measuring the distribution of structure in the Universe, through the statistical properties of the angular distribution of galaxies on the sky. We measure the angular correlation of galaxies from the second data release of the GaLactic and Extragalactic All-sky Murchison Widefield Array eXtended survey (GLEAM-X) survey, a low-frequency radio survey covering declinations below $+30^\circ$. We find an angular distribution consistent with the $\Lambda$CDM cosmological model assuming the best fitting cosmological parameters from Planck Collaboration et al. (2020, A&A, 641, A6). We fit a bias function to the discrete tracers of the underlying matter distribution, finding a bias that evolves with redshift in either a linear or exponential fashion to be a better fit to the data than a constant bias. We perform a covariance analysis to obtain an estimation of the properties of the errors, by analytic, jackknife, and sample variance means. Our results are consistent with previous studies on the topic, and also the predictions of the $\Lambda$CDM cosmological model.
The structure of a disordered IIb Mg-chamosite was studied using Rietveld refinement techniques and powder X-ray diffraction (CuKα, 18–120° 2θ in 0.02° 2θ increments). The refinement in space group CĪ yielded high precision lattice parameters (a = 5.36982(5)Å, b = 9.3031(9)Å, c = 14.2610(6)Å, α = 90.315(5)°, β = 97.234(7)°, γ = 90.022(9)°) and atomic coordinates very similar to previous studies. However, the presence of semi-random stacking in this specimen created a situation in which not all atoms could be precisely located: the positions of the octahedral cations and anions which repeat at intervals of ±b/3 could be uniquely determined in three dimensions whereas only the z parameter of the other atoms could be refined. The reasonable appearance of the final model, despite the fact that many of the atom positions could be located in only one dimension, may have resulted because all of the atoms in this structure except O(5) repeat at intervals which are very nearly ±b/3.
There is increasing recognition of cognitive and pathological heterogeneity in early-stage Alzheimer’s disease and other dementias. Data-driven approaches have demonstrated cognitive heterogeneity in those with mild cognitive impairment (MCI), but few studies have examined this heterogeneity and its association with progression to MCI/dementia in cognitively unimpaired (CU) older adults. We identified cluster-derived subgroups of CU participants based on comprehensive neuropsychological data and compared baseline characteristics and rates of progression to MCI/dementia or a Dementia Rating Scale (DRS) of <129 across subgroups.
Participants and Methods:
A hierarchical cluster analysis was conducted using 11 baseline neuropsychological test scores from 365 CU participants in the UCSD Shiley-Marcos Alzheimer’s Disease Research Center (age M=71.93 years, SD=7.51; 55.9% women; 15.6% Hispanic/Latino/a/x/e). A discriminate function analysis was then conducted to test whether the individual neuropsychological scores predicted cluster-group membership. Cox regressions examined the risk of progression to consensus diagnosis of MCI or dementia, or to DRS score <129, by cluster group.
Results:
Cluster analysis identified 5 groups: All-Average (n=139), Low-Visuospatial (n=46), Low-Executive (n=51), Low-Memory/Language (n=83), and Low-All Domains (n=46). The discriminant function analysis using the neuropsychological measures to predict group membership into these 5 clusters correctly classified 85.2% of the participants. Subgroups had unique demographic and clinical characteristics. Relative to the All-Average group, the Low-Visuospatial (hazard ratio [HR] 2.39, 95% CI [1.03, 5.56], p=.044), Low-Memory/Language (HR 4.37, 95% CI [2.24, 8.51], p<.001), and Low-All Domains (HR 7.21, 95% CI [3.59, 14.48], p<.001) groups had greater risk of progression to MCI/dementia. The Low-Executive group was also twice as likely to progress to MCI/dementia compared to the AllAverage group, but did not statistically differ (HR 2.03, 95% CI [0.88,4.70], p=.096). A similar pattern of results was found for progression to DRS score <129, with the Low-Executive (HR 2.82, 95% CI [1.26, 6.29], p=.012), Low-Memory/Language (HR 3.70, 95% CI [1.80, 7.56], p<.001) and Low-All Domains (HR 5.79, 95% CI [2.74, 12.27], p<.001) groups at greater risk of progression to a DRS score <129 than the All-Average group. The Low-Visuospatial group was also twice as likely to progress to DRS <129 compared to the All-Average group, but did not statistically differ (HR 2.02, 95% CI [0.80, 5.06], p=.135).
Conclusions:
Our results add to a growing literature documenting heterogeneity in the earliest cognitive and pathological presentations associated with Alzheimer’s disease and related disorders. Participants with subtle memory/language, executive, and visuospatial weaknesses all declined at faster rates than the All-Average group, suggesting that there are multiple pathways and/or unique subtle cognitive decline profiles that ultimately lead to a diagnosis of MCI/dementia. These results have important implications for early identification of individuals at risk for MCI/dementia. Given that the same classification approach may not be optimal for everyone, determining profiles of subtle cognitive difficulties in CU individuals and implementing neuropsychological test batteries that assess multiple cognitive domains may be a key step towards an individualized approach to early detection and fewer missed opportunities for early intervention.
From the nineteenth century to the present and covering a range of novelistic styles, Australians have sought imaginative possibilities in the Asia Pacific region. This chapter draws upon an extensive database of Australian writing on Asia to map the variety and range of Australian fiction set in or dealing with Asia. Main genres include invasion novels, which date from the late nineteenth century; a growing body of popular fiction, drawing at first on Asian settings and later employing Asian characters; fiction drawing on narratives of travel; and explorations of Australia’s evolving identity as a predominantly white nation in an Asian region. This chapter is structured around seven key texts which illustrate key themes and modes of writing.
A mix of guidance and mandated regulations during the coronavirus disease (COVID-19) pandemic served to reduce the number of social contacts, to ensure distancing in public spaces, and to maintain the isolation of infected individuals. Individual variation in compliance to social distancing in Germany, relating to age, gender, or the presence of pre-existing health conditions, was examined using results from a total of 39 375 respondents to a web-based behavioral survey.
Older people and females were more willing to engage in social distancing. Those with chronic conditions showed overall higher levels of compliance, but those with cystic fibrosis, human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), and epilepsy showed less adherence to general social distancing measures but were significantly more likely to isolate in their homes. Behavioral differences partly lie in the nature of each condition, especially with those conditions likely to be exacerbated by COVID-19. Compliance differences for age and gender are largely in line with previous studies.
OBJECTIVES/GOALS: 22q.11 deletion syndrome (22q11DS) is a genomic syndrome that elevates risk for psychosis >20-fold. We used a battery of cognitive and psychophysiological psychosis-risk biomarkers in 22q11DS patients and healthy subjects in order to identify biomarkers of psychosis in 22q11DS that could be used as translational targets in intervention studies. METHODS/STUDY POPULATION: We recruited 15 22q11DS individuals (Mean age=30, M/F=9/6) and 19 healthy controls (HCs; Mean age=34, M/F=5/14). Each individual completed the MATRICS Consensus Cognitive Battery (MCCB), the Wechsler Abbreviated Scale of Intelligence, Second edition (WASI-II) Verbal IQ subtests, and the computerized Wisconsin Card Sorting Task (WCST). To examine auditory EEG responses, each participant completed the 'Double-Deviant' target detection paradigm, which presents a pseudorandom sequence of frequent standard tones and infrequent deviant tones. Mismatch negativity (MMN) metrics were generated from this assessment. Welch's t-tests were completed for neurocognitive variables. One-Way ANOVAs were completed to examine EEG results, with sex entered as a separate factor and age entered as a covariate. RESULTS/ANTICIPATED RESULTS: Significant group differences were found in 8 of the 9 neurocognitive measurements (FDR-adjusted p's< 0.02, average Cohen's d=1.62, average observed power= 0.91) indicating widespread cognitive deficits in 22q11DS subjects across multiple domains. The Double-Deviant MMN ERP response was significantly smaller in absolute magnitude in the 22q11DS group (FDR-adjusted p=0.048, Cohen’s d= -0.864, observed power= 0.58). The MMN ERPs for the frequency and duration deviants were not significantly different (FDR-adjusted p's> 0.33). No group by sex interactions were observed in any of the measures. Neurocognitive variables were associated with psychosis positive, negative, general, and disorganized symptom scales. DISCUSSION/SIGNIFICANCE: Our results identify potential psychosis-risk biomarkers in 22q11DS. If replicated, these biomarkers could provide important translational targets for future clinical trials for individuals with 22q11DS and other individuals at-risk for psychosis syndromes.
OBJECTIVES/GOALS: To identify an electroencephalographic (EEG) signature of SOR in adults with TS METHODS/STUDY POPULATION: We will recruit 60 adults with CTD and 60 sex- and age-matched healthy controls to complete scales assessing severity of SOR (Sensory Gating Inventory, SGI), tics, and psychiatric symptoms. Subjects will then be monitored on dense-array scalp EEG during sequential auditory and tactile sensory gating paradigms, as such paradigms have been shown to correlate with self-report measures of SOR in other populations. Single-trial EEG data will be segmented into 100-ms epochs and spectrally deconvoluted into standard frequency bands (delta, theta, alpha, beta, gamma) for pre-defined regions of interest. We will conduct between-group contrasts (Wilcoxon rank-sum) of band-specific sensory gating indices and within-group correlations (Spearman rank correlations) between sensory gating indices and SGI scores. RESULTS/ANTICIPATED RESULTS: We hypothesize that, relative to controls, adults with CTD exhibit impaired sensory gating and that extent of impairment correlates with severity of SOR. 14 adults with CTD (9 men, 5 women) and 16 controls (10 men, 6 women) have completed the protocol to date. Within this sample, adults with CTD showed significantly reduced sensory gating compared to controls in frontal (CTD median 0.12 dB (interquartile range -0.15–0.70 dB); control -0.37 dB (-0.80–-0.13 dB); p = 0.01) and parietal (CTD 0.17 dB (-0.08–0.50 dB); control -0.20 dB (-0.43–0.10 dB); p = 0.01) gamma band during the 100-200 ms epoch in the tactile paradigm. No significant between-group differences were evident for the auditory paradigm. Among adults with CTD, multiple sensory gating indices significantly correlated with SGI scores. Enrollment continues. DISCUSSION/SIGNIFICANCE: Results aim to clarify the extent of sensory gating impairment in TS and identify a clinical correlate of neurophysiologic dysfunction in the disorder. Such knowledge has direct implications for identification of candidate neurophysiologic biomarkers, an express goal of the National Institutes of Health.
Individuals often assess themselves as being less susceptible to common biases compared to others. This bias blind spot (BBS) is thought to represent a metacognitive error. In this research, we tested three explanations for the effect: The cognitive sophistication hypothesis posits that individuals who display the BBS more strongly are actually less biased than others. The introspection bias hypothesis posits that the BBS occurs because people rely on introspection more when assessing themselves compared to others. The conversational processes hypothesis posits that the effect is largely a consequence of the pragmatic aspects of the experimental situation rather than true metacognitive error. In two experiments (N = 1057) examining 18 social/motivational and cognitive biases, there was strong evidence of the BBS. Among the three hypotheses examined, the conversational processes hypothesis attracted the greatest support, thus raising questions about the extent to which the BBS is a metacognitive effect.
This book presents an academically rigorous yet practical guide to efforts to understand how knowledge, policy and power interact to promote or prevent change.
Automated virtual reality therapies are being developed to increase access to psychological interventions. We assessed the experience with one such therapy of patients diagnosed with psychosis, including satisfaction, side effects, and positive experiences of access to the technology. We tested whether side effects affected therapy.
Methods
In a clinical trial 122 patients diagnosed with psychosis completed baseline measures of psychiatric symptoms, received gameChange VR therapy, and then completed a satisfaction questionnaire, the Oxford-VR Side Effects Checklist, and outcome measures.
Results
79 (65.8%) patients were very satisfied with VR therapy, 37 (30.8%) were mostly satisfied, 3 (2.5%) were indifferent/mildly dissatisfied, and 1 (0.8%) person was quite dissatisfied. The most common side effects were: difficulties concentrating because of thinking about what might be happening in the room (n = 17, 14.2%); lasting headache (n = 10, 8.3%); and the headset causing feelings of panic (n = 9, 7.4%). Side effects formed three factors: difficulties concentrating when wearing a headset, feelings of panic using VR, and worries following VR. The occurrence of side effects was not associated with number of VR sessions, therapy outcomes, or psychiatric symptoms. Difficulties concentrating in VR were associated with slightly lower satisfaction. VR therapy provision and engagement made patients feel: proud (n = 99, 81.8%); valued (n = 97, 80.2%); and optimistic (n = 96, 79.3%).
Conclusions
Patients with psychosis were generally very positive towards the VR therapy, valued having the opportunity to try the technology, and experienced few adverse effects. Side effects did not significantly impact VR therapy. Patient experience of VR is likely to facilitate widespread adoption.
Conventionally, intelligence is seen as a property of individuals. However, it is also known to be a property of collectives. Here, we broaden the idea of intelligence as a collective property and extend it to the planetary scale. We consider the ways in which the appearance of technological intelligence may represent a kind of planetary scale transition, and thus might be seen not as something which happens on a planet but to a planet, much as some models propose the origin of life itself was a planetary phenomenon. Our approach follows the recognition among researchers that the correct scale to understand key aspects of life and its evolution is planetary, as opposed to the more traditional focus on individual species. We explore ways in which the concept may prove useful for three distinct domains: Earth Systems and Exoplanet studies; Anthropocene and Sustainability studies; and the study of Technosignatures and the Search for Extraterrestrial Intelligence (SETI). We argue that explorations of planetary intelligence, defined as the acquisition and application of collective knowledge operating at a planetary scale and integrated into the function of coupled planetary systems, can prove a useful framework for understanding possible paths of the long-term evolution of inhabited planets including future trajectories for life on Earth and predicting features of intelligentially steered planetary evolution on other worlds.
The purpose of this article is to celebrate the exquisite moments when enclosed space at Hagia Sophia attains an illusory plastic state. The subject is the secularised amalgamation of the Byzantine cathedral of Hagia Sophia and the Turkish mosque of Ayasofya, prior to the restoration of the mosque in 2020. The article is intended as a visual study of intrinsic visual qualities, without the use of seductive imagery.
To assess the contribution of different food groups to total salt purchases and to evaluate the estimated reduction in salt purchases if mandatory maximum salt limits in South African legislation were being complied with.
Design:
This study conducted a cross-sectional analysis of purchasing data from Discovery Vitality members. Data were linked to the South African FoodSwitch database to determine the salt content of each food product purchased. Food category and total annual salt purchases were determined by summing salt content (kg) per each unit purchased across a whole year. Reductions in annual salt purchases were estimated by applying legislated maximum limits to product salt content.
Setting:
South Africa.
Participants:
The study utilised purchasing data from 344 161 households, members of Discovery Vitality, collected for a whole year between January and December 2018.
Results:
Vitality members purchased R12·8 billion worth of food products in 2018, representing 9562 products from which 264 583 kg of salt was purchased. The main contributors to salt purchases were bread and bakery products (23·3 %); meat and meat products (19 %); dairy (12·2 %); sauces, dressings, spreads and dips (11·8 %); and convenience foods (8·7 %). The projected total quantity of salt that would be purchased after implementation of the salt legislation was 250 346 kg, a reduction of 5·4 % from 2018 levels.
Conclusions:
A projected reduction in salt purchases of 5·4 % from 2018 levels suggests that meeting the mandatory maximum salt limits in South Africa will make a meaningful contribution to reducing salt purchases.
Nutrition during the periconceptional period influences postnatal cardiovascular health. We determined whether in vitro embryo culture and transfer, which are manipulations of the nutritional environment during the periconceptional period, dysregulate postnatal blood pressure and blood pressure regulatory mechanisms. Embryos were either transferred to an intermediate recipient ewe (ET) or cultured in vitro in the absence (IVC) or presence of human serum (IVCHS) and a methyl donor (IVCHS+M) for 6 days. Basal blood pressure was recorded at 19–20 weeks after birth. Mean arterial pressure (MAP) and heart rate (HR) were measured before and after varying doses of phenylephrine (PE). mRNA expression of signaling molecules involved in blood pressure regulation was measured in the renal artery. Basal MAP did not differ between groups. Baroreflex sensitivity, set point, and upper plateau were also maintained in all groups after PE stimulation. Adrenergic receptors alpha-1A (αAR1A), alpha-1B (αAR1B), and angiotensin II receptor type 1 (AT1R) mRNA expression were not different from controls in the renal artery. These results suggest there is no programmed effect of ET or IVC on basal blood pressure or the baroreflex control mechanisms in adolescence, but future studies are required to determine the impact of ET and IVC on these mechanisms later in the life course when developmental programming effects may be unmasked by age.