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Field studies were conducted in 2018 and 2019 in Arkansas, Indiana, Illinois, Missouri, and Tennessee to determine if cover crop residue interfered with herbicides that provide residual control of Palmer amaranth and waterhemp in no−till soybean. The experiments were established in the fall with planting of cover crops (cereal rye plus hairy vetch). Herbicide treatments consisted of a nontreated or no residual, acetochlor, dimethenamid−P, flumioxazin, −pyroxasulfone + flumioxazin, pendimethalin, metribuzin and pyroxasulfone and S−metolachlor. Palmer amaranth took 18 d and waterhemp took 24 d in the cover crop alone (nontreated) treatment to reach a height of 10 cm. Compared with this treatment, all herbicides except metribuzin increased the number of days (d) until 10 cm Palmer amaranth was present. Flumioxazin applied alone or in a mixture with pyroxasulfone were the best at delaying Palmer amaranth growing to a height of 10 cm (35 and 33 d). The herbicides that resulted in the lowest Palmer amaranth density (1.5 to 4x less) integrated with a cover crop were pyroxasulfone + flumioxazin, flumioxazin, pyroxasulfone, and acetochlor. Those four herbicide treatments also delayed Palmer amaranth emergence for the longest period (27 to 34 d). Waterhemp density was 7 to 14 times less with acetochlor than all the other herbicides present. Yield differences were observed for locations with waterhemp. This research agrees with previous research that utilizing soil residual herbicides along with cover crop benefits control of Palmer amaranth and/or waterhemp.
To evaluate the striatal D3/D2 receptor occupancy of cariprazine (RGH-188) in healthy volunteers and schizophrenic patients, and assess the correlation between cariprazine plasma concentration and receptor occupancy.
Single- (0.5 mg) or multiple-dose (1 mg/day, 14 days) cariprazine was administered to healthy adult males (N=5) in an open-label positron emission tomography (PET) study. In a separate open-label PET study, multiple-dose cariprazine (0.5-3.0 mg/day, 14 days) was administered to adult male schizophrenic patients (N=8). Healthy volunteers had 1 predose and 1 postdose raclopride PET scan; schizophrenic patients had 1 predose and up to 3 postdose fallypride scans. Cariprazine plasma concentrations were determined by LC-MS/MS.
In healthy volunteers, single-dose cariprazine 0.5 mg resulted in low plasma concentration (0.1 ng/ml) and was associated with 12% maximum D3/D2 receptor occupancy; cariprazine 1 mg/day for 14 days resulted in cariprazine plasma concentrations of 2.3-3.4 ng/ml and >70% D3/D2 receptor occupancy. In schizophrenic patients, cariprazine 1.5 mg/day for 14 days resulted in cariprazine plasma concentrations of 2.5-3.4 ng/ml and >70% receptor occupancy; cariprazine 3.0 mg/day resulted in ≥90% occupancy. Predicted Emax values in schizophrenic patients approached 100% D3/D2 occupancy for dorsal and ventral striatum.
D3/D2 receptor occupancy in dorsal and ventral striatum was similar for cariprazine 1.0 mg/day in healthy volunteers and cariprazine 1.5 mg/day in schizophrenic patients. In both, higher receptor occupancy was associated with higher cariprazine plasma concentration. Cariprazine at 1.5 to 3.0 mg/day showed D3/D2 receptor occupancy within the predicted effective antipsychotic range.
En France, la consommation de psychotropes est élevée, en particulier chez les personnes âgées. Personnes âgées QUID (« PAQUID ») est une étude de cohorte menée sur 3777 personnes âgées de plus de 65 ans et vivant à leur domicile, en Gironde ou en Dordogne, depuis 1988. Durant la période de l’étude, des guides de bonne pratique et des alertes ont été publiés par les agences gouvernementales, afin de favoriser, encadrer et optimiser la prescription des médicaments psychotropes, notamment chez les personnes âgées. L’objectif de cette étude est d’évaluer si les caractéristiques associées à la consommation de médicaments psychotropes ont changé entre la période 1988–1998 et la période 2001–2008 chez les sujets âgés de 75 ans et plus.
Les données analysées sont issues de la cohorte PAQUID menée sur 3777 sujets de plus de 65 ans. Des analyses par régression logistique multivariée ont été utilisées pour identifier les facteurs explicatifs de l’usage de psychotropes, globalement et pour chaque classe, sur les deux périodes.
Sur les deux périodes, plus de la moitié des sujets consommaient des psychotropes. La consommation d’antidépresseurs a plus que doublé entre la première et la seconde période. Être une femme, présenter une démence ou une dépression, être dépendant pour les activités quotidiennes, consommer plus de neufs médicaments augmentent la probabilité de consommer des psychotropes.
La consommation de psychotropes semble augmenter entre les deux périodes. On observe quelques changements en ce qui concerne la consommation de psychotropes globalement et les consommations des classes plus spécifiques. Ces changements peuvent être en lien avec des recommandations des autorités de santé sur le traitement de la dépression et l’arrivée sur le marché de nouveaux produits. D’autres semblent moins explicables.
Emerging evidence suggests that sedentary behaviour, specifically time spent taking part in screen-based activities, such as watching television, may be associated with mental health outcomes in young people . However, recent reviews have found limited and conflicting evidence for both anxiety and depression .
The purpose of the study was to explore associations between screen time at age 16 years and anxiety and depression at 18.
Subjects (n = 1958) were from the Avon Longitudinal Study of Parents and Children (ALSPAC), a UK-based prospective cohort study. We assessed associations between screen time (measured via questionnaire at 16 years) and anxiety and depression (measured in a clinic at 18 years using the Revised Clinical Interview Schedule) using ordinal logistic regression, before and after adjustment for covariates (including sex, maternal education, family social class, parental conflict, bullying and maternal depression).
After adjusting for potential confounders, we found no evidence for an association between screen time and anxiety (OR = 1.02; 95% CI 0.95–1.09). There was weak evidence that greater screen time was associated with a small increased risk of depression (OR = 1.05, 95% CI 0.98–1.13).
Our results suggest that young people who spend more time on screen-based activities may have a small increased risk of developing depression but not anxiety. Reducing youth screen time may lower the prevalence of depression. The study was limited by screen time being self-reported, a small sample size due to attrition and non-response, and the possibility of residual confounding. Reverse causation cannot be ruled out.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Observational associations between cannabis and schizophrenia are well documented, but ascertaining causation is more challenging. We used Mendelian randomization (MR), utilizing publicly available data as a method for ascertaining causation from observational data.
We performed bi-directional two-sample MR using summary-level genome-wide data from the International Cannabis Consortium (ICC) and the Psychiatric Genomics Consortium (PGC2). Single nucleotide polymorphisms (SNPs) associated with cannabis initiation (p < 10−5) and schizophrenia (p < 5 × 10−8) were combined using an inverse-variance-weighted fixed-effects approach. We also used height and education genome-wide association study data, representing negative and positive control analyses.
There was some evidence consistent with a causal effect of cannabis initiation on risk of schizophrenia [odds ratio (OR) 1.04 per doubling odds of cannabis initiation, 95% confidence interval (CI) 1.01–1.07, p = 0.019]. There was strong evidence consistent with a causal effect of schizophrenia risk on likelihood of cannabis initiation (OR 1.10 per doubling of the odds of schizophrenia, 95% CI 1.05–1.14, p = 2.64 × 10−5). Findings were as predicted for the negative control (height: OR 1.00, 95% CI 0.99–1.01, p = 0.90) but weaker than predicted for the positive control (years in education: OR 0.99, 95% CI 0.97–1.00, p = 0.066) analyses.
Our results provide some that cannabis initiation increases the risk of schizophrenia, although the size of the causal estimate is small. We find stronger evidence that schizophrenia risk predicts cannabis initiation, possibly as genetic instruments for schizophrenia are stronger than for cannabis initiation.
A segment of the debate surrounding the commercialization and use of glyphosate-resistant (GR) crops focuses on the theory that the implementation of these traits is an extension of the intensification of agriculture that will further erode the biodiversity of agricultural landscapes. A large field-scale study was initiated in 2006 in the United States on 156 different field sites with a minimum 3-yr history of GR-corn, -cotton or -soybean in the cropping system. The impact of cropping system, crop rotation, frequency of using the GR crop trait, and several categorical variables on seedbank weed population density and diversity was analyzed. The parameters of total weed population density of all species in the seedbank, species richness, Shannon's H′ and evenness were not affected by any management treatment. The similarity between the seedbank and aboveground weed community was more strongly related to location than management; previous year's crops and cropping systems were also important while GR trait rotation was not. The composition of the weed flora was more strongly related to location (geography) than any other parameter. The diversity of weed flora in agricultural sites with a history of GR crop production can be influenced by several factors relating to the specific method in which the GR trait is integrated (cropping system, crop rotation, GR trait rotation), the specific weed species, and the geographical location. Continuous GR crop, compared to fields with other cropping systems, only had greater species diversity (species richness) of some life forms, i.e., biennials, winter annuals, and prostrate weeds. Overall diversity was related to geography and not cropping system. These results justify further research to clarify the complexities of crops grown with herbicide-resistance traits to provide a more complete characterization of their culture and local adaptation to the weed seedbank.
A clearer understanding of the basis for the association between cannabis use and psychotic experiences (PEs) is required. Our aim was to examine the extent to which associations between cannabis and cigarette use and PEs are due to confounding.
A cohort study of 1756 adolescents with data on cannabis use, cigarette use and PEs.
Cannabis use and cigarette use at age 16 were both associated, to a similar degree, with PEs at age 18 [odds ratio (OR) 1.48, 95% confidence interval (CI) 1.18–1.86 for cannabis and OR 1.61, 95% CI 1.31–1.98 for cigarettes]. Adjustment for cigarette smoking frequency (OR 1.27, 95% CI 0.91–1.76) or other illicit drug use (OR 1.25, 95% CI 0.91–1.73) substantially attenuated the relationship between cannabis and PEs. The attenuation was to a lesser degree when cannabis use was adjusted for in the cigarette PE association (OR 1.42, 95% CI 1.05–1.92). However, almost all of the participants used cannabis with tobacco, including those who classed themselves as non-cigarette smokers.
Teasing out the effects of cannabis from tobacco is highly complex and may not have been dealt with adequately in studies to date, including this one. Complementary methods are required to robustly examine the independent effects of cannabis, tobacco and other illicit drugs on PEs.
An argument often used to support the view that psychotic experiences (PEs) in general population samples are a valid phenotype for studying the aetiology of schizophrenia is that risk factors for schizophrenia show similar patterns of association with PEs. However, PEs often co-occur with depression, and no study has explicitly tested whether risk factors for schizophrenia are shared between PEs and depression, or are psychopathology specific, while jointly modelling both outcomes.
We used data from 7030 subjects from a birth cohort study. Depression and PEs at age 18 years were assessed using self-report questionnaires and semi-structured interviews. We compared the extent to which risk factors for schizophrenia across sociodemographic, familial, neurodevelopmental, stress–adversity, emotional–behavioural and substance use domains showed different associations with PEs and depression within bivariate models that allowed for their correlation.
Most of the exposures examined were associated, to a similar degree, with an increased risk of both outcomes. However, whereas female sex and family history of depression showed some discrimination as potential risk factors for depression and PEs, with stronger associations in the former, markers of abnormal neurodevelopment showed stronger associations with PEs.
The argument that PEs are valid markers for studying the aetiology of schizophrenia, made simply on the basis that they share risk factors in common, is not well supported. PEs seem to be a weak index of genetic and environmental risk for schizophrenia; however, studies disentangling aetiological pathways to PEs from those impacting upon co-morbid psychopathology might provide important insights into the aetiology of psychotic disorders.
To assess the prevalence and risk factors for colonization with Staphylococcus aureus in inmates entering two maximum-security prisons in New York State, USA, inmates (N = 830) were interviewed and anterior nares and oropharyngeal samples collected. Isolates were characterized using spa typing. Overall, 50·5% of women and 58·3% of men were colonized with S. aureus and 10·6% of women and 5·9% of men were colonized with MRSA at either or both body sites. Of MSSA isolates, the major subtypes were spa type 008 and 002. Overall, risk factors for S. aureus colonization varied by gender and were only found in women and included younger age, fair/poor self-reported general health, and longer length of prior incarceration. Prevalence of MRSA colonization was 8·2%, nearly 10 times greater than in the general population. Control of epidemic S. aureus in prisons should consider the constant introduction of strains by new inmates.
Poor fetal growth is associated with later-life changes in adult body composition and decrements in muscle strength and morphology. Few studies have investigated the association of poor fetal growth with whole-body exercise. The purpose of this study was to investigate the association of poor fetal growth with the maximal oxygen consumption (VO2max), lactate levels during exercise and the response to aerobic training. Thirty-six college-aged men and women (aged 20.8 ± 0.3 years), born to term (37–42 weeks gestation), were recruited to participate in an 8-week training program. Participants comprised two groups, high ponderal index (HIGHPI) and low ponderal index (LOWPI) (n = 18/group), identified as falling above and below the 10th percentile of the ponderal index (g/cm3)-for-gestational age distribution, respectively. The HIGHPI and LOWPI were matched pair-wise on age, sex, body mass index and pre-study physical activity patterns. The LOWPI and HIGHPI did not differ significantly before training, after training or with a change (Δ) in training VO2max (l/min or ml/min kg/fat-free mass (FFM)). However, LOWPI had significantly lower pre-training lactate levels at similar levels of relative work output (P = 0.016), and significantly smaller decreases in lactate at a fixed level of absolute work after training (P = 0.044). These differences were independent of pre-training aerobic fitness, the change in fitness with training, diet and fuel substrate choice. The lower lactate of untrained LOWPI subjects during exercise could reflect metabolic reprograming due to intrauterine growth restriction, or could be secondary to muscle morphological and/or fiber-type distribution changes that also associate with poor fetal growth.
The effects of salient testing parameters on four-point adhesion measurements of thin-film structures on silicon substrates were systematically studied. These included specimen geometry, applied displacement rate, and load point separation. Measured fracture energy values, Gc, were observed to increase as the ratio of applied moment arm to specimen thickness was decreased beyond a value of ∼4, particularly for specimens with Gc > 5 J/m2. Testing parameters that affect the steady-state crack velocity were also found to affect reported Gc values. The resulting trends in Gc values are shown to be related to loading-point friction and environmentally assisted cracking effects. Good practice testing guidelines are suggested to improve the accuracy and precision of four-point bend measurements.
The susceptibility of Pseudomonas aeruginosa (PA01) bacteria to ultraviolet-A (UV-A) light in photocatalytic and non-photocatalytic systems was investigated. Thin films of TiO2 were deposited on glass slides using a dip-coating method. Disinfection of both planktonic and biofilm bacterial cells was studied over both coated and uncoated slides exposed to low intensity (1.0 mW/cm2) UV-A irradiation. Photocatalytic treatment of planktonic PA01 cultures pro-vided a 4-log reduction in the number of viable cells in 3 h whereas UV light alone produced a 1-log reduction. For biofilm bacteria, photocatalytic treatment did not enhance killing relative to UV treatment alone; however, the UV illumination resulted in a 2- to 3-log reduction in viable cells as compared with non-illuminated controls. Possible explanations for the discrepancy between susceptibility of planktonic and biofilm bacteria to photocatalytic oxidation are discussed.
Predicting the threat of extinction aids efficient distribution of conservation resources. This paper utilises a comparative macroecological approach to investigate the threat of extinction in Neotropical birds. Data on ecological variables for 1708 species are analysed using stepwise regression to produce minimum adequate models, first using raw species values and then using independent contrasts (to control for phylogenetic effects). The models differ, suggesting phylogeny has significant effects. The raw species analysis reveals that number of zoogeographical regions occupied, elevational range and utilisation of specialised microhabitats were negatively associated with threat, while minimum elevation and body mass were positively associated, whereas the independent contrasts analysis only identifies zoogeographical regions as important. Confining the analysis to the 582 species restricted to a single zoogeographical region reveals elevational range and number of habitats occupied to be negatively correlated with threat whether the analysis is based on the raw data or on independent contrasts. Analysis of four contrasting zoogeographical regions highlights regional variation in the models. In two Andean regions the threat of extinction declines as the elevation range across which the species occurs increases. In the presence of substantial human populations on high Andean plateaus, a species with a greater elevational range may be more likely to persist at some (relatively) unsettled altitudes. In Central South America, the strongest predictor of threat is minimum elevation of occurrence: species with a lower minimum are less threatened. The minimum elevation result suggests that lowland species experiencing an ecological limit to their minimum elevation (min. elevation >0 m) may be more at risk than those not experiencing such a limit (min. elevation = 0 m). Finally, in southern Amazonia, where there is little altitudinal variation, the only weak predictors of threat are body size, larger species being more threatened, and number of habitats, species occupying more habitats being less threatened. These contrasting results emphasise the importance of undertaking extinction risk analyses at an appropriate geographical scale. Since the models explained only a low percentage of total variance in the data, the effects of human-mediated habitat disturbance across a wide range of habitats may be important.
This paper briefly describes the principle of operation and science goals of the AMANDA high energy neutrino telescope located at the South Pole, Antarctica. Results from an earlier phase of the telescope, called AMANDA-BIO, demonstrate both reliable operation and the broad astrophysical reach of this device, which includes searches for a variety of sources of ultrahigh energy neutrinos: generic point sources, Gamma-Ray Bursts and diffuse sources. The predicted sensitivity and angular resolution of the telescope were confirmed by studies of atmospheric muon and neutrino backgrounds. We also report on the status of the analysis from AMANDA-II, a larger version with far greater capabilities. At this stage of analysis, details of the ice properties and other systematic uncertainties of the AMANDA-II telescope are under study, but we have made progress toward critical science objectives. In particular, we present the first preliminary flux limits from AMANDA-II on the search for continuous emission from astrophysical point sources, and report on the search for correlated neutrino emission from Gamma Ray Bursts detected by BATSE before decommissioning in May 2000. During the next two years, we expect to exploit the full potential of AMANDA-II with the installation of a new data acquisition system that records full waveforms from the in-ice optical sensors.
Estimation of variance components with the finite polygenic model (FPM) was evaluated.
Phenotypic data for a 6300-pedigree simulated under a wide range of additive genetic models were
analysed with constant homozygote difference across loci using deterministic Maximum Likelihood
(DML) and a Bayesian method implemented via Gibbs sampling (BGS). Results indicate that
under no selection, both DML and BGS accurately estimated the variance components, with a
FPM of 5 loci or more. When both analysis methods were applied to equivalent data sets on
populations that had undergone selection, the DML method produced upward biased estimates of
additive genetic variation and heritability due to its use of pedigree loop cutting, while BGS
provided more accurate estimation. BGS was extended to non-additive FPMs with variable
homozygote differences and dominance effect across loci. This method was used to analyse data
simulated under two genetic models with positive, completely dominant gene action at all loci.
Results indicate that the estimates of additive and dominance variances slowly increase as the
number of loci in the FPM for analysis increases, while accuracy of predicting individual breeding
values and dominance deviations remains unaffected. For the simulated pedigree structure, a FPM
with 10 loci or slightly fewer appears to be appropriate for variance component estimation in the
presence of dominance.
The astropectinid asteroid Plutonaster bifrons (Wyville Thomson) occurs on the continental slope of the north-east Atlantic between 1000 and 2500 m depths. As in most deepsea animals, the factors limiting bathymetric distribution of this species are unknown. Eggs were fertilized in vitro and incubated through the early embryonic cleavage stages at pressures that correspond to depths from 0 to 3000 m. The highest percentage of normal development occurred near the peak of the species distribution (2000 m), and virtually no normal development occurred at a pressure corresponding to 3000 m depth. Develop-mental rate was retarded at pressures higher and lower than those found near 2000 m. These experiments indicate that embryonic pressure tolerances could determine both the upper and lower bathymetric limits of distribution for this species.
We evaluated the effects of free-range chickens and geese on insect pests and weeds in an experimental, nonchemical agroecosystem consisting of an apple orchard with intercropped potatoes. The objective was to assess the potential of these domestic bird species as biological control agents. Four insect pests were studied: plum curculio, apple maggot, Japanese beetle, and Colorado potato beetle. Chickens fed on several potential crop pests, including Japanese beetle. Although Japanese beetles were less abundant on apple trees when chickens were present, the proportion of damaged fruit was not reduced. Furthermore, chickens did not affect weed abundance or crop productivity. In contrast, geese were effective weeders. Their activities reduced weed abundance and increased potato plant growth and yields compared with a minimally weeded control. In addition, the activities of geese indirectly reduced apple fruit damage by plum curculio and increased the proportion of pest-free fruit, possibly because removal of vegetation by the geese reduced humidity at the soil surface and therefore reduced the activity of plum curculio.