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The Σ-invariants of Bieri–Neumann–Strebel and Bieri–Renz involve an action of a discrete group G on a geometrically suitable space M. In the early versions, M was always a finite-dimensional Euclidean space on which G acted by translations. A substantial literature exists on this, connecting the invariants to group theory and to tropical geometry (which, actually, Σ-theory anticipated). More recently, we have generalized these invariants to the case where M is a proper CAT(0) space on which G acts by isometries. The “zeroth stage” of this was developed in our paper [BG16]. The present paper provides a higher-dimensional extension of the theory to the “nth stage” for any n.
Lee and Schwarz interpret meta-analytic research and replication studies as providing evidence for the robustness of cleansing effects. We argue that the currently available evidence is unconvincing because (a) publication bias and the opportunistic use of researcher degrees of freedom appear to have inflated meta-analytic effect size estimates, and (b) preregistered replications failed to find any evidence of cleansing effects.
Fast pixelated detectors incorporating direct electron detection (DED) technology are increasingly being regarded as universal detectors for scanning transmission electron microscopy (STEM), capable of imaging under multiple modes of operation. However, several issues remain around the post-acquisition processing and visualization of the often very large multidimensional STEM datasets produced by them. We discuss these issues and present open source software libraries to enable efficient processing and visualization of such datasets. Throughout, we provide examples of the analysis methodologies presented, utilizing data from a 256 × 256 pixel Medipix3 hybrid DED detector, with a particular focus on the STEM characterization of the structural properties of materials. These include the techniques of virtual detector imaging; higher-order Laue zone analysis; nanobeam electron diffraction; and scanning precession electron diffraction. In the latter, we demonstrate a nanoscale lattice parameter mapping with a fractional precision ≤6 × 10−4 (0.06%).
This is a secondary analysis of clinical trial data collected in 12 European countries. We examined changes in weight and weight-related quality of life among community patients with schizophrenia treated with aripiprazole (ARI) versus standard of care (SOC), consisting of other marketed atypical antipsychotics (olanzapine, quetiapine, and risperidone).
Five-hundred and fifty-five patients whose clinical symptoms were not optimally controlled and/or experienced tolerability problems with current medication were randomized to ARI (10–30 mg/day) or SOC. Weight and weight-related quality of life (using the IWQOL-Lite) were assessed at baseline, and weeks 8, 18 and 26. Random regression analysis across all time points using all available data was used to compare groups on changes in weight and IWQOL-Lite. Meaningful change from baseline was also assessed.
Participants were 59.7% male, with a mean age of 38.5 years (SD 10.9) and mean baseline body mass index of 27.2 (SD 5.1). ARI participants lost an average of 1.7% of baseline weight in comparison to a gain of 2.1% by SOC participants (p < 0.0001) at 26 weeks. ARI participants experienced significantly greater increases in physical function, self-esteem, sexual life, and IWQOL-Lite total score. At 26 weeks, 20.7% of ARI participants experienced meaningful improvements in IWQOL-Lite score, versus 13.5% of SOC participants. A clinically meaningful change in weight was also associated with a meaningful change in quality of life (p < 0.001). A potential limitation of this study was its funding by a pharmaceutical company.
Compared to standard of care, patients with schizophrenia treated with aripiprazole experienced decreased weight and improved weight-related quality of life over 26 weeks. These changes were both statistically and clinically significant.
Given the evidence of multi-parameter risk factors in shaping cognitive outcomes in aging, including sleep, inflammation, cardiometabolism, and mood disorders, multidimensional investigations of their impact on cognition are warranted. We sought to determine the extent to which self-reported sleep disturbances, metabolic syndrome (MetS) factors, cellular inflammation, depressive symptomatology, and diminished physical mobility were associated with cognitive impairment and poorer cognitive performance.
This is a cross-sectional study.
Participants with elevated, well-controlled blood pressure were recruited from the local community for a Tai Chi and healthy-aging intervention study.
One hundred forty-five older adults (72.7 ± 7.9 years old; 66% female), 54 (37%) with evidence of cognitive impairment (CI) based on Montreal Cognitive Assessment (MoCA) score ≤24, underwent medical, psychological, and mood assessments.
CI and cognitive domain performance were assessed using the MoCA. Univariate correlations were computed to determine relationships between risk factors and cognitive outcomes. Bootstrapped logistic regression was used to determine significant predictors of CI risk and linear regression to explore cognitive domains affected by risk factors.
The CI group were slower on the mobility task, satisfied more MetS criteria, and reported poorer sleep than normocognitive individuals (all p < 0.05). Multivariate logistic regression indicated that sleep disturbances, but no other risk factors, predicted increased risk of evidence of CI (OR = 2.00, 95% CI: 1.26–4.87, 99% CI: 1.08–7.48). Further examination of MoCA cognitive subdomains revealed that sleep disturbances predicted poorer executive function (β = –0.26, 95% CI: –0.51 to –0.06, 99% CI: –0.61 to –0.02), with lesser effects on visuospatial performance (β = –0.20, 95% CI: –0.35 to –0.02, 99% CI: –0.39 to 0.03), and memory (β = –0.29, 95% CI: –0.66 to –0.01, 99% CI: –0.76 to 0.08).
Our results indicate that the deleterious impact of self-reported sleep disturbances on cognitive performance was prominent over other risk factors and illustrate the importance of clinician evaluation of sleep in patients with or at risk of diminished cognitive performance. Future, longitudinal studies implementing a comprehensive neuropsychological battery and objective sleep measurement are warranted to further explore these associations.
Transcatheter stent implantation has been employed to treat re-coarctation of the aorta in adolescents and young adults. The aim of this work is to use computational fluid dynamics to characterise haemodynamics associated with re-coarctation involving an aneurysmal ductal ampulla and aortic isthmus narrowing, which created minimal pressure drop, and to incorporate computational fluid dynamics’s findings into decision-making concerning catheter-directed treatment.
Computational fluid dynamics permits numerically solving the Navier–Stokes equations governing pulsatile flow in the aorta, based on patient-specific data. We determined flow-velocity fields, wall shear stresses, oscillatory shear indices, and particle stream traces, which cannot be ascertained from catheterisation data or magnetic resonance imaging.
Computational fluid dynamics showed that, as flow entered the isthmus, it separated from the aortic wall, and created vortices leading to re-circulating low-velocity flow that induced low and multidirectional wall shear stress, which could sustain platelet-mediated thrombus formation in the ampulla. In contrast, as flow exited the isthmus, it created a jet leading to high-velocity flow that induced high and unidirectional wall shear stress, which could eventually undermine the wall of the descending aorta.
We used computational fluid dynamics to study re-coarctation involving an aneurysmal ductal ampulla and aortic isthmus narrowing. Despite minimal pressure drop, computational fluid dynamics identified flow patterns that would place the patient at risk for: thromboembolic events, rupture of the ampulla, and impaired descending aortic wall integrity. Thus, catheter-directed stenting was undertaken and proved successful. Computational fluid dynamics yielded important information, not only about the case presented, but about the complementary role it can serve in the management of patients with complex aortic arch obstruction.
The traditional living donor was very healthy. However, as the supply-demand gap continues to expand, transplant programs have become more accepting of less healthy donors. This paper focuses on the other extreme, asking whether and when individuals who have life-limiting conditions (LLC) should be considered for living organ donation. We discuss ethical issues raised by 1) donation by individuals with progressive severe debilitating disease for whom there is no ameliorative therapy; and 2) donation by individuals who are imminently dying or would die by the donation process itself.
To describe the epidemiology of surgical site infections (SSIs) after pediatric ambulatory surgery.
Observational cohort study with 60 days follow-up after surgery.
The study took place in 3 ambulatory surgical facilities (ASFs) and 1 hospital-based facility in a single pediatric healthcare network.
Children <18 years undergoing ambulatory surgery were included in the study. Of 19,777 eligible surgical encounters, 8,502 patients were enrolled.
Data were collected through parental interviews and from chart reviews. We assessed 2 outcomes: (1) National Healthcare Safety Network (NHSN)–defined SSI and (2) evidence of possible infection using a definition developed for this study.
We identified 21 NSHN SSIs for a rate of 2.5 SSIs per 1,000 surgical encounters: 2.9 per 1,000 at the hospital-based facility and 1.6 per 1,000 at the ASFs. After restricting the search to procedures completed at both facilities and adjustment for patient demographics, there was no difference in the risk of NHSN SSI between the 2 types of facilities (odds ratio, 0.7; 95% confidence interval, 0.2–2.3). Within 60 days after surgery, 404 surgical patients had some or strong evidence of possible infection obtained from parental interview and/or chart review (rate, 48 SSIs per 1,000 surgical encounters). Of 306 cases identified through parental interviews, 176 cases (57%) did not have chart documentation. In our multivariable analysis, older age and black race were associated with a reduced risk of possible infection.
The rate of NHSN-defined SSI after pediatric ambulatory surgery was low, although a substantial additional burden of infectious morbidity related to surgery might not have been captured by standard surveillance strategies and definitions.
To integrate electronic clinical decision support tools into clinical practice and to evaluate the impact on indwelling urinary catheter (IUC) use and catheter-associated urinary tract infections (CAUTIs).
Design, Setting, and Participants
This 4-phase observational study included all inpatients at a multicampus, academic medical center between 2011 and 2015.
Phase 1 comprised best practices training and standardization of electronic documentation. Phase 2 comprised real-time electronic tracking of IUC duration. In phase 3, a triggered alert reminded clinicians of IUC duration. In phase 4, a new IUC order (1) introduced automated order expiration and (2) required consideration of alternatives and selection of an appropriate indication.
Overall, 2,121 CAUTIs, 179,070 new catheters, 643,055 catheter days, and 2,186 reinsertions occurred in 3·85 million hospitalized patient days during the study period. The CAUTI rate per 10,000 patient days decreased incrementally in each phase from 9·06 in phase 1 to 1·65 in phase 4 (relative risk [RR], 0·182; 95% confidence interval [CI], 0·153–0·216; P<·001). New catheters per 1,000 patient days declined from 53·4 in phase 1 to 39·5 in phase 4 (RR, 0·740; 95% CI, 0·730; P<·001), and catheter days per 1,000 patient days decreased from 194·5 in phase 1 to 140·7 in phase 4 (RR, 0·723; 95% CI, 0·719–0·728; P<·001). The reinsertion rate declined from 3·66% in phase 1 to 3·25% in phase 4 (RR, 0·894; 95% CI, 0·834–0·959; P=·0017).
The phased introduction of decision support tools was associated with progressive declines in new catheters, total catheter days, and CAUTIs. Clinical decision support tools offer a viable and scalable intervention to target hospital-wide IUC use and hold promise for other quality improvement initiatives.
Singh's cultural evolutionary theory of shamanism is impressive, but it does not explain why some people become shamans while others do not. We propose that individual differences in where people lie on a “psychosis continuum” could play an important causal role.
Boyer & Petersen (B&P) argue that folk-economic beliefs are widespread – shaped by evolved cognitive systems – and they offer exemplar beliefs to illustrate their thesis. In this commentary, we highlight evidence of substantial variation in one of these exemplars: beliefs about immigration. Contra claims by B&P, we argue that the balance of this evidence suggests the “folk” may actually hold positive beliefs about the economic impact of immigration.
The Khoesan were the first people in Africa to undergo the full rigours of European colonisation. By the early nineteenth century, they had largely been brought under colonial rule, dispossessed of their land and stock, and forced to work as labourers for farmers of European descent. Nevertheless, a portion of them were able to regain a degree of freedom and maintain their independence by taking refuge in the mission stations of the Western and Eastern Cape, most notably in the Kat River valley. For much of the nineteenth century, these Khoesan people kept up a steady commentary on, and intervention in, the course of politics in the Cape Colony. Through petitions, speeches at meetings, letters to the newspapers and correspondence between themselves, the Cape Khoesan articulated a continuous critique of the oppressions of colonialism, always stressing the need for equality before the law, as well as their opposition to attempts to limit their freedom of movement through vagrancy legislation and related measures. This was accompanied by a well-grounded distrust, in particular, of the British settlers of the Eastern Cape and a concomitant hope, rarely realised, in the benevolence of the British government in London. Comprising 98 of these texts, These Oppressions Won’t Cease – an utterance expressed by Willem Uithaalder, commander of Khoe rebel forces in the war of 1850-3 – contains the essential documents of Khoesan political thought in the nineteenth century. These texts of the Khoesan provide a history of resistance to colonial oppression which has largely faded from view. Robert Ross, the eminent historian of precolonial South Africa, brings back their voices from the annals of the archive, voices which were formative in the establishment of black nationalism in South Africa, but which have long been silenced.
In the aftermath of the rebellion, the world had changed. The inhabitants of the Kat River valley and of the mission stations no longer had the confidence to challenge the racist order that came to prevail in the Cape. The rebellion was crushing in its effects, even for those who had remained steadfastly loyal, as the Kat River valley was, as far as possible, opened up to white settlement. The levels of authority which the original settlers in the valley had held over their lives were undermined. Men of Khoekhoe descent were systematically excluded from any positions of responsibility, and any land that came free was granted to whites, under the pretext that this would provide a leavening of the racially exclusive settlement. In fact, of course, it was the beginning of a long process of dispossession.
In these circumstances, Khoekhoe politics turned increasingly inwards. Although on occasion Khoekhoe descendants did participate in public debates on a variety of issues, most notably on the attempts to partition the colony between the Western and the Eastern Provinces, in general political energy was expended on the details of the new settlement in the Kat River valley, and above all on the organisation of the various churches. It was both a sphere in which the Khoe could still wield power, and one which was under threat as the funding for mission churches declined and the call went up that congregations of converts, and increasingly of men and women brought up in the faith, should be financially self-supporting and independent.
For the effects of drink and the work of temperance societies among the Khoekhoe, see Document 9.
3 May 1847
Memorial to Sir Henry Young, (Lt. Governor) from inhabitants of Bethelsdorp.
That memorialists have been informed that the present proprietors of a portion of the estate Perseverance situated on the High Road to Graham's Town at the Wagon Drift of Zwartkops River intend establishing a canteen at said place for the sale of wine and brandy. That being convinced canteens are prejudicial to morals any where, one in such a situation as the above named will prove especially injurious to the morals of many who constantly travel the road, they consider it a duty to bring the subject under Your Honor's notice. Memorialists conceive there are several weighty objections to the erection of a Canteen at such a place; the distance from Port Elizabeth being only 11 miles, and from Uitenhage 8 or 9 miles such an establishment is unnecessary. The injurious effects which would be produced on the labouring classes daily passing would be exceedingly great. As numbers of waggons employed in the conveyance of Government stores and goods for merchants are constantly passing, doubtless the canteen would prove a snare to many leaders and drivers, many would become intoxicated, and rendered unfit to proceed on their journey with their wagons. Memorialists believe that a canteen would not merely be a cause of detention to many wagons, but from the numbers who would meet together to drink much quarrelling, fighting and other disorderly conduct would take place. Leaders and drivers being unable to manage their teams the number of accidents on the road especially when the river is high, would be greatly increased. Memorialists beg also to state that there is no Police at hand whose officers might check any disorderly conduct which would undoubtedly arise.
Memorialists therefore most humbly solicit your Honor to take these circumstances into consideration and that it may please your Honor to direct that no Licence for opening a canteen at Zwartkops River drift be granted.
And your Memorialists as in duty bound will ever pray.