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Adaptive management studies of invasive plants on non-agricultural lands typically employ an empirical approach based on designed field experiments that permit rigorous statistical analysis of results to quantify outcomes and assess the efficacy of management practices. When habitat restoration is the primary goal of a project, traditional plot-based study designs (e.g., the randomized complete-block design) are sometimes infeasible (this is often true in aquatic habitats) or inappropriate (e.g., when the goal is to assess effects of management practices on survival or resprouting of individual plants, such as trees or shrubs). Moreover, the assumptions of distribution-specific parametric statistical methods such as ANOVA often cannot be convincingly verified or are clearly untenable when properly assessed. For these reasons, it is worthwhile to be aware of alternative study designs that do not employ plots as experimental units and nonparametric statistical methods that require only weak distributional assumptions. The purpose of this paper is to review several of these alternative study designs and nonparametric statistical methods that we have found useful in our own studies of invasive aquatic and terrestrial plants. We motivate each statistical method by a research question it is well suited to answer, provide corresponding references to the statistical literature, and identify at least one R function that implements the method. In the Supplementary Material, we present additional technical information about the statistical methods, numerical examples with data, and a set of complete R programs to illustrate application of the statistical methods.
In response to the COVID-19 pandemic, we rapidly implemented a plasma coordination center, within two months, to support transfusion for two outpatient randomized controlled trials. The center design was based on an investigational drug services model and a Food and Drug Administration-compliant database to manage blood product inventory and trial safety.
Methods:
A core investigational team adapted a cloud-based platform to randomize patient assignments and track inventory distribution of control plasma and high-titer COVID-19 convalescent plasma of different blood groups from 29 donor collection centers directly to blood banks serving 26 transfusion sites.
Results:
We performed 1,351 transfusions in 16 months. The transparency of the digital inventory at each site was critical to facilitate qualification, randomization, and overnight shipments of blood group-compatible plasma for transfusions into trial participants. While inventory challenges were heightened with COVID-19 convalescent plasma, the cloud-based system, and the flexible approach of the plasma coordination center staff across the blood bank network enabled decentralized procurement and distribution of investigational products to maintain inventory thresholds and overcome local supply chain restraints at the sites.
Conclusion:
The rapid creation of a plasma coordination center for outpatient transfusions is infrequent in the academic setting. Distributing more than 3,100 plasma units to blood banks charged with managing investigational inventory across the U.S. in a decentralized manner posed operational and regulatory challenges while providing opportunities for the plasma coordination center to contribute to research of global importance. This program can serve as a template in subsequent public health emergencies.
Given increased survival for adults with CHD, we aim to determine outcome differences of infective endocarditis compared to patients with structurally normal hearts in the general population.
Methods:
We conducted a retrospective cross-sectional study identifying infective endocarditis hospitalisations in patients 18 years and older from the National Inpatient Sample database between 2001 and 2016 using International Classification of Disease diagnosis and procedure codes. Weighting was used to create national annual estimates indexed to the United States population, and multivariable logistic regression analysis determined variable associations. Outcome variables were mortality and surgery. The primary predictor variable was the presence or absence of CHD.
Results:
We identified 1,096,858 estimated infective endocarditis hospitalisations, of which 17,729 (1.6%) were adults with CHD. A 125% increase in infective endocarditis hospitalisations occurred for adult CHD patients during the studied time period (p < 0.001). Adults with CHD were significantly less likely to experience mortality (5.4% vs. 9.5%, OR 0.54, CI 0.47–0.63, p < 0.001) and more likely to undergo in-hospital surgery (31.6% vs. 6.7%, OR 6.49, CI 6.03–6.98, p < 0.001) compared to the general population. CHD severity was not associated with increased mortality (p = 0.53). Microbiologic aetiology of infective endocarditis varied between groups (p < 0.001) with Streptococcus identified more commonly in adults with CHD compared to patients with structurally normal hearts (36.2% vs. 14.4%).
Conclusions:
Adults with CHD hospitalised for infective endocarditis are less likely to experience mortality and more likely to undergo surgery than the general population.
A new iron oxide dissolution method designed to measure the abundance of “free” Fe oxide phases and associated elements in soils and sediments has been tested. The method employs a ternary complex of Ti(III), citrate, and ethylenediaminetetraacetate (EDTA) as a reductant and bicarbonate as a proton acceptor. The Ti(III)-citrate-EDTA-HCO3 method dissolved more synthetic amorphous ferric oxide and goethite, but less synthetic hematite, than the dithionite-citrate-HCO3 method of Mehra and Jackson. The production of acidity by the dissolution indicated that Ti(IV) is hydrolyzed to TiO2 during the extractions. The heated dithionite method dissolved 3–6 times more Al from kaolinite and nontronite standard clays than room temperature dithionite, and 4–6 times more Al than the Ti(III)-citrate-EDTA-HCO3 method. Furthermore, the release of Fe from the clay mineral samples consistently and rapidly reached a plateau during multiple extractions by the Ti(III)-citrate-EDTA-HCO3 method, indicating that a well-defined Fe oxide fraction was removed. Fe released by the dithionite method continued to increase with each extraction, suggesting that some release of structural Fe occurred. Tests on two natural sediments and one heavy mineral fraction from the Miocene Cohansey Sand in the New Jersey Coastal Plain suggested that the Ti(III)-citrate-EDTA-HCO3 method removed Fe oxides more effectively and more selectively than the dithionite method. The selectivity of the Ti(III)-citrate-EDTA-HCO3 method is enhanced by rapid extractions at room temperature and low free ligand concentrations.
Large-scale geological structures have controlled the long-term development of the bed and thus the flow of the West Antarctic Ice Sheet (WAIS). However, complete ice cover has obscured the age and exact positions of faults and geological boundaries beneath Thwaites Glacier and Pine Island Glacier, two major WAIS outlets in the Amundsen Sea sector. Here, we characterize the only rock outcrop between these two glaciers, which was exposed by the retreat of slow-flowing coastal ice in the early 2010s to form the new Sif Island. The island comprises granite, zircon U-Pb dated to ~177–174 Ma and characterized by initial ɛNd, 87Sr/86Sr and ɛHf isotope compositions of -2.3, 0.7061 and -1.3, respectively. These characteristics resemble Thurston Island/Antarctic Peninsula crustal block rocks, strongly suggesting that the Sif Island granite belongs to this province and placing the crustal block's boundary with the Marie Byrd Land province under Thwaites Glacier or its eastern shear margin. Low-temperature thermochronological data reveal that the granite underwent rapid cooling following emplacement, rapidly cooled again at ~100–90 Ma and then remained close to the Earth's surface until present. These data help date vertical displacement across the major tectonic structure beneath Pine Island Glacier to the Late Cretaceous.
Adverse environments are linked to elevated youth antisocial behavior. However, this relation is thought to depend, in part, on genetic susceptibility. The present study investigated whether polygenic risk for antisociality moderates relations between hostile environments and stable as well as dynamic antisocial behaviors across adolescence. We derived two antisocial-linked polygenic risk scores (PRS) (N = 721) based on previous genome-wide association studies. Forms of antisocial behavior (nonaggressive conduct problems, physical aggression, social aggression) and environmental hostility (harsh parenting and school violence) were assessed at age 13, 15, and 17 years. Relations to individual differences stable across adolescence (latent stability) vs. time-specific states (timepoint residual variance) of antisocial behavior were assessed via structural equation models. Higher antisocial PRS, harsh parenting, and school violence were linked to stable elevations in antisocial behaviors across adolescence. We identified a consistent polygenic-environment interaction suggestive of differential susceptibility in late adolescence. At age 17, harsher parenting was linked to higher social aggression in those with higher antisocial PRS, and lower social aggression in those with lower antisocial PRS. This suggests that genetics and environmental hostility relate to stable youth antisocial behaviors, and that genetic susceptibility moderates home environment-antisocial associations specifically in late adolescence.
When present at elevated levels in drinking water, arsenic is toxic, and magnesian clays are gaining recognition as a source of elevated arsenic in groundwater. In the crust and upper mantle of Earth, arsenic incorporation into clay minerals is influenced by geochemical conditions associated with hydrothermal fluids and metamorphic processes (e.g. serpentinization), meaning that As is a useful tracer of fluid-flow in the deep Earth. To improve understanding of arsenic speciation in groundwater, sediments, soils, and hydrothermal-metamorphic systems, the present study examined arsenic incorporation into magnesian clays by synthesis of serpentine minerals (200oC, 10 d) with varied concentrations of Si, Al, As5+, and As3+. The synthesis experiments produced two distinct crystal types, tubular and platy serpentines, each with 10–15% randomly interstratified talc layers. X-ray absorption spectroscopy indicated that As5+ and As3+ occurred in the tetrahedral sheet. Single-crystal analysis revealed that tubular crystals contained up to 1 wt.% arsenic [Mg2.8(Si1.8As0.2)O5(OH)4] (mean 0.2 wt.% As). The mean composition of platy, high-Al crystals is (Mg1.8Al0.7)(Si2.0)O5(OH)4, and that of platy, medium-Al crystals with As3+ is (Mg2.07Al0.52) (Si1.97As3+0.03)O5(OH)4. Charge, geometry, and radius of tetrahedral AsO43– oxyanions are similar to tetrahedral SiO44–, and this facilitates fixation of As5+ into the tetrahedral sheet of clay minerals. The geometry and size of the larger As3+ in tetrahedral sites (as a pyramidal AsO33– oxyanion) may limit incorporation relative to As5+. Arsenic-bearing Mg clays crystallize in alkaline environments where AsO43– or AsO33– are the dominant As species and where high pH accompanies crystallization of serpentine, talc, chlorite, or Mg-smectite. The presence of tetrahedral As in these clays raises the possibility of tetrahedral As in other Mg clays (e.g. sepiolite or kerolite) as well.
Tropical soils range from nutrient-depleted lateritic soils rich in halloysite or kaolinite to Inceptisols rich in interstratified kaolinite-smectite (K-S), smectite, or related 2:1 clays. Given the strong influence of clay minerals on tropical soil quality, better understanding of factors influencing their occurrence is important for modeling and managing tropical environments. This study examines the alteration of smectite to kaolinite by way of intermediate K-S and halloysite in a 120 ka moist tropical chronosequence. Iron-rich smectite (11.6 ± 2.2% Fe2O3) is the dominant mineral in Holocene soils (1–8 ka) originating from sediments rich in plagioclase and clinopyroxene. The cation exchange capacity (CEC) of smectite is 54–84 cmolc/kg and pH is 6.1 to 7.4. Within 50 ka, smectite fixes Al-hydroxy complexes into interlayers, K+ is retained preferentially over Ca2+, and 2:1 layers are stripped of tetrahedral sheets; the resulting K-S inherits flaky smectite crystal habit and the 2:1 layers — which only expand partially — include Al-hydroxy smectite and some illite-like layers. After 50 ka, the dominant mineral is K-S, the CEC is 18–28 cmolc/kg, and the pH is 5.3. Flaky Fe-kaolinite with ~10% residual smectite layers and halloysite (7.4% Fe2O3) also occur in 50 ka soil. The 120 ka soils are dominated by flaky Fe-kaolinite (<10% residual smectite layers) and halloysite (4.9% Fe2O3), and Fe-poor hexagonal kaolinite also occurs (5–10% of soil). The CEC is 11–16 cmolc/kg and the pH is 4.7–5.3.
Changes in crystal chemistry of the soil clays (decreasing Fe, Mg, Ca, and K; increasing Al) over time reflects two reaction mechanisms: (1) cell-preserved transformation of smectite layers to kaolinite layers that accompanies conversion of smectite to K-S and eventually kaolinite; this results in the formation of flaky Fe-rich kaolinites after 50 ka; and (2) dissolution of K-S followed by crystallization of halloysite. Neoformation of hexagonal kaolinite and/or halloysite with low Fe (<3% Fe2O3) follows dissolution of Fe-kaolinite or halloysite after 100 ka. This sequence is probably common in moist tropical soils and these findings may inform modeling of soil composition in tropical landscapes where tectonic, volcanic, or geomorphic activity periodically exposes unweathered parent material, producing a range of soil ages.
We tested 85 isolates of β-hemolytic Streptococcus spp. against trimethoprim/sulfamethoxazole (TMP/SMX), clindamycin, and doxycycline by broth microdilution (BMD) and BD Phoenix. Susceptibility rates via BMD for TMP/SMX, clindamycin, and doxycycline were 100%, 85.5%, and 56.6%, respectively. TMP/SMX is a potential monotherapy agent for β-hemolytic Streptococcus skin and soft tissue infections.
This study investigated the effects of Lacticaseibacillus rhamnosus HN001 supplementation on the architecture and gene expression in small intestinal tissues of piglets used as an animal model for infant humans. Twenty-four 10-d-old entire male piglets (4·3 (sd 0·59) kg body weight) were fed an infant formula (IF) (control) or IF supplemented with 1·3 × 105 (low dose) or 7·9 × 106 (high dose) colony-forming units HN001 per ml of reconstituted formula (n 8 piglets/treatment). After 24 d, piglets were euthanised. Samples were collected to analyse the histology and gene expression (RNAseq and qPCR) in the jejunal and ileal tissues, blood cytokine concentrations, and blood and faecal calprotectin concentrations. HN001 consumption altered (false discovery rate < 0·05) gene expression (RNAseq) in jejunal tissues but not in ileal tissues. The number of ileal goblet cells and crypt surface area increased quadratically (P < 0·05) as dietary HN001 levels increased, but no increase was observed in the jejunal tissues. Similarly, blood plasma concentrations of IL-10 and calprotectin increased linearly (P < 0·05) as dietary HN001 levels increased. In conclusion, supplementation of IF with HN001 affected the architecture and gene expression of small intestine tissue, blood cytokine concentration and frequencies, and blood calprotectin concentrations, indicating that HN001 modulated small intestinal tissue maturation and immunity in the piglet model.
We present the third data release from the Parkes Pulsar Timing Array (PPTA) project. The release contains observations of 32 pulsars obtained using the 64-m Parkes ‘Murriyang’ radio telescope. The data span is up to 18 yr with a typical cadence of 3 weeks. This data release is formed by combining an updated version of our second data release with $\sim$3 yr of more recent data primarily obtained using an ultra-wide-bandwidth receiver system that operates between 704 and 4032 MHz. We provide calibrated pulse profiles, flux density dynamic spectra, pulse times of arrival, and initial pulsar timing models. We describe methods for processing such wide-bandwidth observations and compare this data release with our previous release.
The Harmonized Cognitive Assessment Protocol (HCAP) describes an assessment battery and a family of population-representative studies measuring neuropsychological performance. We describe the factorial structure of the HCAP battery in the US Health and Retirement Study (HRS).
Method:
The HCAP battery was compiled from existing measures by a cross-disciplinary and international panel of researchers. The HCAP battery was used in the 2016 wave of the HRS. We used factor analysis methods to assess and refine a theoretically driven single and multiple domain factor structure for tests included in the HCAP battery among 3,347 participants with evaluable performance data.
Results:
For the eight domains of cognitive functioning identified (orientation, memory [immediate, delayed, and recognition], set shifting, attention/speed, language/fluency, and visuospatial), all single factor models fit reasonably well, although four of these domains had either 2 or 3 indicators where fit must be perfect and is not informative. Multidimensional models suggested the eight-domain model was overly complex. A five-domain model (orientation, memory delayed and recognition, executive functioning, language/fluency, visuospatial) was identified as a reasonable model for summarizing performance in this sample (standardized root mean square residual = 0.05, root mean square error of approximation = 0.05, confirmatory fit index = 0.94).
Conclusions:
The HCAP battery conforms adequately to a multidimensional structure of neuropsychological performance. The derived measurement models can be used to operationalize notions of neurocognitive impairment, and as a starting point for prioritizing pre-statistical harmonization and evaluating configural invariance in cross-national research.
Non-communicable diseases (NCD) such as CVD and type 2 diabetes mellitus are major contributors to the burden of disease. NCD are largely driven by modifiable lifestyle factors including poor diet and insufficient physical activity, and consequently, prevention is a public health priority. Although diet and physical activity levels can be improved via lifestyle interventions, long-term adherence to such interventions remains low, which limits their effectiveness. Thus, it is critical to identify the underlying mechanisms that challenge uptake and adherence to such interventions. The current commentary discusses an important, but underexplored, psychological driver of poor adherence to lifestyle interventions, namely, future discounting, which describes the tendency to prefer smaller, short-term rewards over larger, long-term rewards. For example, in the nutrition domain, future discounting refers to valuing the immediate reward of excessive intake of energy-dense, nutrient-poor, discretionary foods high in salt, sugar, and saturated fat, and insufficient intake of low-energy, nutrient-dense, whole foods such as vegetables. Prominent theoretical models propose that excessive future discounting is a major contributor to the development of unhealthy lifestyle behaviours. Furthermore, a vast body of evidence suggests that future discounting plays a key role in risk of NCD. Thus, the evidence to date supports the idea that future discounting is an important multi-behaviour target for supporting lifestyle behaviour change; however, this approach has been largely neglected in preventive health efforts. Furthermore, this commentary discusses promising techniques (e.g. Episodic Future Thinking) for disrupting future discounting to promote improved adherence to lifestyle interventions aimed at reducing NCD risk.
Sound general and sports nutrition knowledge in athletes is essential for making appropriate dietary choices. Assessment of nutrition knowledge enables evaluation and tailoring of nutrition education. However, few well-validated tools are available to assess nutrition knowledge in athletes. The objective of the present study was to establish the validity of the Platform to Evaluate Athlete Knowledge Sports – Nutrition Questionnaire (PEAKS-NQ) for use in the United Kingdom and Irish (UK-I) athletes. To confirm content validity, twenty-three sports nutritionists (SNs) from elite, UK-I sports institutes provided feedback on the PEAKS-NQ via a modified Delphi method. After minor changes, the UK-I version of the PEAKS-NQ was administered to UK-I SN from the British Dietetic Association Sport and Exercise Nutrition Register, and elite athletes (EA) training at elite sports institutes in the UK and Ireland. Independent samples t-test and independent samples median tests were used to compare PEAKS-NQ total and subsection scores between EA and SN (to assess construct validity). Cronbach's alpha (good ≥ 0⋅7) was used to establish internal consistency. The SN achieved greater overall [SN (n 23) 92⋅3 (9⋅3) v. EA (n 154): 71⋅4 (10⋅0)%; P < 0⋅001] and individual section scores (P < 0⋅001) except Section B, Identification of Food Groups (P = 0⋅07). Largest knowledge differences between SN and EA were in Section D, Applied Sports Nutrition [SN: 88⋅5 (8⋅9) v. EA: 56⋅7 (14⋅5)%; P < 0⋅00]. Overall ES was large (2⋅1), with subsections ranging from 0⋅6 to 2⋅3. Cronbach's alpha was good (0⋅83). The PEAKS-NQ had good content and construct validity, supporting its use to assess nutrition knowledge of UK-I athletes.
We examine whether state judicial selection methods influence people’s evaluations of US Supreme Court nominees. We find that people from appointing states use nominee characteristics in their evaluations differently than people in electing states. Those from appointing states appear to be more concerned with traditional legal factors, while people from electing states appear to be slightly less concerned with them. Although the importance varies from characteristic to characteristic, state judicial selection system has a broad role in shaping how people evaluate judicial nominees. These findings counsel further research on judicial institutions and the public’s expectations of judges.
We examine whether the public evaluates Supreme Court nominees on the basis of judicial philosophies when presented with a description of those philosophies. Employing a conjoint experiment, we find that the public will evaluate nominees’ judicial philosophies as well as the nominees’ partisanship, ideology, and qualifications. We also discover significant differences between Republicans and Democrats. These results have important implications for the future of judicial nominations, framing, and public support for the judiciary.
Many families, despite need and eligibility, struggle to meet programme deadlines to retain critical benefits. When families fail to complete programme recertification on time, they lose needed support. While scholars have tested behavioural theories like chunking, implementation intention, and loss framing to promote programme uptake, less is known about how well-designed communications can promote continuity through successful recertification, especially where recertification entails a significant administrative burden. Further, scant evidence guides how best to frame recertification deadlines. In a randomised trial with government partners (n = 3,539), we find that sending a reminder letter informed by these behavioural theories increased the number of families maintaining participation by 14 per cent. Further, anchoring people to a deadline month may suffice to thread the motivational needle: overcoming procrastination without lowering self-efficacy by anchoring them to a specific day. Adopting the most effective letter in Washington, DC, would lead 766 more families to participate uninterrupted each year.
Purposeful adults may experience greater cognitive resilience because sense of purpose may help buffer against the effects of depressive symptoms and loneliness. We also evaluated whether these associations differed by race.
Design:
This study uses a wave of self-report data from the SPAN study of psychosocial aging.
Setting:
Participants come from a representative sample of older adults in St. Louis.
Participants:
Participants (N = 595) ages range from 65 to 78 (Mage = 71.46), with 18.3% of participants identifying as Black/African-American.
Measures:
Sense of purpose was assessed with the Life Engagement Test, depressive symptoms with the Beck Depression Inventory-II, loneliness with the UCLA Loneliness Scale, and subjective cognitive decline with the AD-8.
Results:
Correlational analyses supported predictions that sense of purpose was negatively related to subjective cognitive decline, whereas depressive symptoms and loneliness were positively related (|r|s > .30, ps < .001). For loneliness, but not depression, this association was moderated by sense of purpose (b = −0.43, p < .001). A relatively high sense of purpose attenuated associations between loneliness and subjective cognitive decline. A three-way race × purpose × loneliness interaction (b = −0.25, p = .021) revealed that the buffering effects of sense of purpose on subjective cognitive decline were stronger for Black adults.
Discussion:
This study provided partial support for the buffering hypothesis, showing that sense of purpose may help mitigate the cognitive decrements associated with loneliness. Future research needs to consider how purpose-promoting programs may support healthy cognitive aging, particularly among Black older adults and those who experience greater social isolation.
To evaluate efficiency and impact of a novel antimicrobial stewardship program (ASP) prospective-audit-with-feedback (PAF) review process using the Cerner Multi-Patient Task List (MPTL).
Design:
Retrospective cohort study.
Setting:
A 367-bed free-standing, pediatric academic medical center.
Methods:
The ASP PAF review process expanded to monitor all systemic and inhaled antibiotics through use of the MPTL on July 23, 2020. Average number of daily ASP reviews, absolute number of monthly interventions, and time to conduct ASP reviews were compared between the preimplementation period and the postimplementation period following expansion. Antibiotic days of therapy (DOT) per 1,000 patient days for overall and select antibiotics were compared between periods. ASP intervention characteristics were assessed.
Results:
Average daily ASP reviews significantly increased following program expansion (9 vs 14 reviews; P < .0001), and the absolute number of ASP interventions each month also increased (34 vs 52 interventions; P ≤ .0001). Time to conduct daily ASP reviews increased in the postimplementation period (1.03 vs 1.32 hours). Overall antibiotic DOT per 1,000 patient days significantly decreased in the postimplementation period (457.9 vs 427.9; P < .0001) as well as utilization of select, narrow-spectrum antibiotics such as ampicillin and clindamycin. Intervention type and antibiotics were similar between periods. The ASP documented 128 “nonantibiotic interventions” in the postimplementation period, including culture and/or susceptibility testing (32.8%), immunizations (25.8%), and additional diagnostic testing (22.7%).
Conclusions:
Implementation of an ASP PAF review process using the MPTL allowed for efficient expansion of a pre-existing ASP and a decrease in overall antibiotic utilization. ASP documentation was enhanced to fully track the impact of the program.