Embedded performance validity tests (PVTs) allow for continuous and economical validity assessment during neuropsychological evaluations; however, similar to their freestanding counterparts, a ...limitation of well-validated embedded PVTs is that the majority are memory-based. This study cross-validated several previously identified non-memory-based PVTs derived from language, processing speed, and executive functioning tests within a single mixed clinical neuropsychiatric sample with and without cognitive impairment.
This cross-sectional study included data from 124 clinical patients who underwent outpatient neuropsychological evaluation. Validity groups were determined by four independent criterion PVTs (failing ≤1 or ≥2), resulting in 98 valid (68% cognitively impaired) and 26 invalid performances. In total, 23 previously identified embedded PVTs derived from Verbal Fluency (VF), Trail Making Test (TMT), Stroop (SCWT), and Wisconsin Card Sorting Test (WCST) were examined.
All VF, SCWT, and TMT PVTs, along with WCST Categories, significantly differed between validity groups (η
p
2 =.05-.22) with areas under the curve (AUCs) of.65-.81 and 19-54% sensitivity (≥89% specificity) at optimal cut-scores. When subdivided by impairment status, all PVTs except for WCST Failures to Maintain Set were significant (AUCs =.75-94) with 33-85% sensitivity (≥90% specificity) in the cognitively unimpaired group. Among the cognitively impaired group, most VF, TMT, and SCWT PVTs remained significant, albeit with decreased accuracy (AUCs =.65-.76) and sensitivities (19-54%) at optimal cut-scores, whereas all WCST PVTs were nonsignificant. Across groups, SCWT embedded PVTs evidenced the strongest psychometric properties.
VF, TMT, and SCWT embedded PVTs generally demonstrated moderate accuracy for identifying invalid neuropsychological performance. However, performance on these non-memory-based PVTs from processing speed and executive functioning tests are not immune to the effects of cognitive impairment, such that alternate cut-scores (with reduced sensitivity if adequate specificity is maintained) are indicated in cases where the clinical history is consistent with cognitive impairment. In contrast, WCST indices generally had poor accuracy.
The minimization of compliance subject to a mass constraint is the topology optimization design problem of interest. The goal is to determine the optimal configuration of material within an allowed ...volume. Our approach builds upon the well-known density method in which the decision variable is the material density in every cell in a mesh. In it’s most basic form the density method consists of three steps: 1) the problem is convexified by replacing the integer material indicator function with a volume fraction, 2) the problem is regularized by filtering the volume fraction field to impose a minimum length scale; 3) the filtered volume fraction is penalized to steer the material distribution toward binary designs. The filtering step is used to yield a mesh-independent solution and to eliminate checkerboard instabilities. In image processing terms this is a low-pass filter, and a consequence is that the decision variables are not independent and a change of basis could significantly reduce the dimension of the nonlinear programming problem. Based on this observation, we represent the volume fraction field with a truncated Fourier representation. This imposes a minimal length scale on the problem, eliminates checkerboard instabilities, and also reduces the number of decision variables by over 100 × (two dimensions) or 1000 × (three dimensions).
Using three design fields we develop an optimization environment that can simultaneously optimize material, shape and topology. We use the implicit representation of the boundaries with level-set ...functions that define the shape and topology. Differentiable R-functions allow us to combine these shapes and topology descriptions with Boolean operations. Additionally, we incorporate design dependent-stiffness materials with another design field. Notably, this framework accommodates design dependent loads, has the ability to introduce holes, and ensures the satisfaction of optimality criteria. It builds upon the fictitious domain, ersatz material, material interpolation and level-set methods. It also borrows from parameterized density-based topology optimization methods. Since analytical sensitivities can be computed, we use efficient nonlinear programming algorithms to update the design instead of the Hamilton–Jacobi’s scheme of level-set methods. We illustrate the features of our framework by designing a cantilever beam with octet truss microlattice, a dam with design-dependent loads, and a composite clevis plate.
•The use of three design fields allows to simultaneously optimize shape, topology, and material.•Implicit modeling with R-functions is used to define the boundary of complex shapes.•This representation accommodates design dependent loads.
In early 1817 the “Ultra-royalist” Poet Laureate of England, Robert Southey, opened a newspaper and saw an advertisement for a radical play he had written in his “Ultra-jacobin” youth back in late ...1794 (the phrases are William Hazlitt’s). “By whose roguery it has got to the press I do not know,” Southey told John Murray. Southey directed his lawyers to initiate a suit in the Court of Chancery requesting an injunction against the publishers on the grounds that “the author has a property in an unpublished work.” But because he had not established his property in the work, the injunction was denied. Furthermore, the Lord Chancellor indicated that his decision was informed by the precedent “that a person cannot recover in damages for a work which is, in its nature calculated to do injury to the public.” The absence of copyright then produced an artificially rapid tranching down in price, flooding the market with cheap editions of the play, while the high-profile affirmation of the precedent provided a certain degree of legal cover for publishers of radical piracies and paved the way for a mass market in radical print. How the play came to be published, however, has remained a mystery. New evidence reveals much of the roguery by which Wat Tyler got to the press and deepens our understanding of political culture, religious Dissent, and publishing practices during the Romantic era.
Objective
Physical activity is recommended to mitigate functional limitations associated with knee osteoarthritis (OA). However, it is unclear whether walking on its own protects against the ...development of functional limitation.
Methods
Walking over 7 days was objectively measured as steps/day within a cohort of people with or at risk of knee OA from the Multicenter Osteoarthritis Study. Incident functional limitation over 2 years was defined by performance‐based (gait speed <1.0 meter/second) and self‐report (Western Ontario and McMaster Universities Osteoarthritis Index physical function score >28 of 68) measures. We evaluated the association of steps/day at baseline with developing functional limitation 2 years later by calculating risk ratios adjusted for potential confounders. The number of steps/day that best distinguished risk for developing functional limitation was estimated from the maximum distance from chance on receiver operating characteristic curves.
Results
Among 1,788 participants (mean age 67 years, mean body mass index 31 kg/m2, 60% women), each additional 1,000 steps/day was associated with a 16% and 18% reduction in incident functional limitation by performance‐based and self‐report measures, respectively. Walking <6,000 and <5,900 steps/day were the best thresholds to distinguish incident functional limitation by performance‐based (sensitivity 67.3%, specificity 71.8%) and self‐report (sensitivity 58.7%, specificity 68.9%) measures, respectively.
Conclusion
More walking was associated with less risk of functional limitation over 2 years. Walking >6,000 steps/day provides a preliminary estimate of the level of walking activity to protect against developing functional limitation in people with or at risk of knee OA.
Abstract
In the face of the current global extinction crisis, it is critical we give conservation management strategies the best chance of success. Australia is not exempt from global trends with ...currently the world’s greatest mammal extinction rate (~ 1 per 8 years). Many more are threatened including the dibbler (
Parantechinus apicalis
) whose remnant range has been restricted to Western Australia at just one mainland site and two small offshore islands—Whitlock Island (5 ha) and Boullanger Island (35 ha). Here, we used 14 microsatellite markers to quantify genetic variation in the remaining island populations from 2013 to 2018 and incorporated these data into population viability analysis (PVA) models, used to assess factors important to dibbler survival and to provide guidance for translocations. Remnant population genetic diversity was low (< 0.3), and populations were highly divergent from each other (pairwise F
ST
s 0.29–0.52). Comparison of empirical data to an earlier study is consistent with recent declines in genetic diversity and models projected increasing extinction risk and declining genetic variation in the next century. Optimal translocation scenarios recommend 80 founders for new dibbler populations—provided by captive breeding—and determined the proportion of founders from parental populations to maximise genetic diversity and minimise harvesting impact. The goal of our approach is long-term survival of genetically diverse, self-sustaining populations and our methods are transferable. We consider mixing island with mainland dibblers to reinforce genetic variation.
This study describes the method development for bioethanol production from three species of seaweed.
Laminaria digitata
,
Ulva lactuca
and for the first time
Dilsea carnosa
were used as ...representatives of brown, green and red species of seaweed, respectively. Acid thermo-chemical and entirely aqueous (water) based pre-treatments were evaluated, using a range of sulphuric acid concentrations (0.125–2.5 M) and solids loading contents (5–25 % w/v; biomass: reactant) and different reaction times (5–30 min), with the aim of maximising the release of glucose following enzyme hydrolysis. A pre-treatment step for each of the three seaweeds was required and pre-treatment conditions were found to be specific to each seaweed species.
Dilsea carnosa
and
U. lactuca
were more suited with an aqueous (water-based) pre-treatment (yielding 125.0 and 360.0 mg of glucose/g of pre-treated seaweed, respectively), yet interestingly non pre-treated
D. carnosa
yielded 106.4 g g
−1
glucose.
Laminaria digitata
required a dilute acid thermo-chemical pre-treatment in order to liberate maximal glucose yields (218.9 mg glucose/g pre-treated seaweed). Fermentations with
S. cerevisiae
NCYC2592 of the generated hydrolysates gave ethanol yields of 5.4 g L
−1
, 7.8 g L
−1
and 3.2 g L
−1
from
D. carnosa
,
U. lactuca
and
L. digitata
, respectively. This study highlighted that entirely aqueous based pre-treatments are effective for seaweed biomass, yet bioethanol production alone may not make such bio-processes economically viable at large scale.
The lipid envelope of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an essential component of the virus; however, its molecular composition is undetermined. Addressing this ...knowledge gap could support the design of antiviral agents as well as further our understanding of viral-host protein interactions, infectivity, pathogenicity, and innate immune system clearance. Lipidomics revealed that the virus envelope comprised mainly phospholipids (PLs), with some cholesterol and sphingolipids, and with cholesterol/phospholipid ratio similar to lysosomes. Unlike cellular membranes, procoagulant amino-PLs were present on the external side of the viral envelope at levels exceeding those on activated platelets. Accordingly, virions directly promoted blood coagulation. To investigate whether these differences could enable selective targeting of the viral envelope in vivo, we tested whether oral rinses containing lipid-disrupting chemicals could reduce infectivity. Products containing PL-disrupting surfactants (such as cetylpyridinium chloride) met European virucidal standards in vitro; however, components that altered the critical micelle concentration reduced efficacy, and products containing essential oils, povidone-iodine, or chlorhexidine were ineffective. This result was recapitulated in vivo, where a 30-s oral rinse with cetylpyridinium chloride mouthwash eliminated live virus in the oral cavity of patients with coronavirus disease 19 for at least 1 h, whereas povidone-iodine and saline mouthwashes were ineffective. We conclude that the SARS-CoV-2 lipid envelope i) is distinct from the host plasma membrane, which may enable design of selective antiviral approaches; ii) contains exposed phosphatidylethanolamine and phosphatidylserine, which may influence thrombosis, pathogenicity, and inflammation; and iii) can be selectively targeted in vivo by specific oral rinses.
For optimal health benefits, moderate- to vigorous-intensity physical activity (MVPA) is recommended in sustained bouts lasting ≥10 min. However, short spurts of MVPA lasting <10 min are more common ...in everyday life. It is unclear whether short spurts of MVPA further protect against the development of hypertension and obesity in middle-age adults beyond bouted MVPA.
Objectively measured physical activity was collected in the Coronary Artery Risk Development in Young Adults study at the 20-yr (2005-2006) examination, and blood pressure and BMI were collected at the 20- and 25-yr (2010-2011) examinations. Time spent in MVPA was classified as either bouted MVPA, i.e., ≥10 continuous minutes or short spurts of MVPA, i.e., <10 continuous minutes. To examine the association of short spurts of MVPA with incident hypertension and obesity over 5 yr, we calculated risk ratios adjusted for bouted MVPA and potential confounders.
Among 1531 and 1251 participants without hypertension and obesity, respectively, at year 20 (age, 45.2 ± 3.6 yr; 57.3% women; body mass index, 29.0 ± 7.0 kg·m(-2)), 14.8% and 12.1% developed hypertension and obesity by year 25. Study participants in the highest tertile of short spurts of MVPA were 31% less likely to develop hypertension 5 yr later (risk ratio = 0.69 (0.49-0.96)) compared with those in the lowest tertile. There was no statistically significant association of short spurts of MVPA with incident obesity.
These findings support the notion that accumulating short spurts of MVPA protects against the development of hypertension but not obesity in middle-age adults.
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