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Greenhouse and outdoor container experiments were conducted to determine garden spurge and large crabgrass emergence when seeds were placed either on top of or below three different mulch materials [pine bark (PB), hardwood (HW), or pine straw (PS)] applied at five depths (0, 1.3, 2.5, 5.1, and 10.2 cm). To elucidate mulch characteristics that contributed to weed control, photosynthetic active radiation (PAR) was recorded underneath each mulch layer, moisture retention was monitored for 24 h following irrigation, and particle size was determined using standard soil sieves. HW reduced PAR (97%) more than did PB (90%) or PS (92%) at 1.3 cm, but few or no differences were noted between mulches at greater mulch depths. HW also contained the highest percentage of small particles and consequently retained more water (29%), than PB (14%) or PS (22%) 24 h following a simulated irrigation event. Emergence of large crabgrass and garden spurge was consistently greater when seeds were placed on top of the mulch, compared to seeds placed below. Emergence of both species also tended to respond to increasing depth in a quadratic manner, indicating that once a critical level of mulch was applied (2.5 to 5 cm), further reductions in weed emergence would not be observed, at least over the short term (12 wk). PB and PS tended to provide a greater reduction in emergence of both species compared to HW. This research also indicates that larger particle materials such as PB or PS would be advantageous because of their ability to suppress weed emergence regardless of seed position.
Weed management in container crops is primarily accomplished through frequent PRE herbicide applications and supplemental hand weeding. However, many ornamental species are sensitive to herbicides, and a significant number of tropical plants, ornamental grasses, and foliage crops have not been screened for herbicide tolerance. As nursery crops are produced in inert substrates that are largely composed of bark or peat, strategic fertilizer placement has the potential to significantly reduce weed growth in container-grown ornamentals. Growth and reproduction of three common container nursery weed species, eclipta [Eclipta prostrata (L.) L.], large crabgrass [Digitaria sanguinalis (L.) Scop.], and spotted spurge (Euphorbia maculata L.), were evaluated following fertilization via alternative methods, including subdressing or dibbling in comparison with industry standard practices of topdressing or incorporating a controlled-release fertilizer (17-5-11 [8 to 9 mo.]) to each 3.8-L container at 36.5 g per container. Fertilizer placement had little to no effect on germination of Eclipta prostrata or D. sanguinalis, but incorporation increased E. maculata germination by 77% to 183% compared with other placements or a nonfertilized control. Subdressing reduced seed production by 94%, 63%, and 92% for Eclipta prostrata, D. sanguinalis, and E. maculata, respectively, compared with the average number of seeds produced in the conventional placement methods (average of incorporation and topdressing). Dibbling fertilizer resulted in similar decreases in the case of D. sanguinalis and E. maculata, while Eclipta prostrata produced no seeds when fertilizer was dibbled. Similar to reductions observed in reproduction, subdressing fertilizer resulted in biomass decreases of 90%, 81%, and 85% compared with the average biomass of the incorporation and topdressed placements. Results suggest alternative fertilizer placements could be implemented as part of an integrated weed management program in container production to reduce weed growth.
A non-perturbative nonlinear theory for moderately dense gas–solid suspensions is outlined within the framework of the Boltzmann–Enskog equation by extending the work of Saha & Alam (J. Fluid Mech., vol. 833, 2017, pp. 206–246). A linear Stokes’ drag law is adopted for gas–particle interactions, and the viscous dissipation due to hydrodynamic interactions is incorporated in the second-moment equation via a density-corrected Stokes number. For the homogeneous shear flow, the present theory provides a unified treatment of dilute to dense suspensions of highly inelastic particles, encompassing the high-Stokes-number rapid granular regime (
) and its small-Stokes-number counterpart, with quantitative agreement for all transport coefficients. It is shown that the predictions of the shear viscosity and normal-stress differences based on existing theories deteriorate markedly with increasing density as well as with decreasing Stokes number and restitution coefficient.
Naticid taxonomy is in a state of flux owing to non-descript shell morphology and frequent convergence. Inadequate preservation of naticid body fossils has further complicated the matter in determining the true affinity and the exact time of origin of the clade. As a result, a plethora of classificatory schemes of naticid phylogeny and times of origin has been proposed. In many previous studies, true naticid affinities of fossils have been sought based on single or a few morphological characters, which are susceptible to poor preservation. In the present paper, we have attempted a holistic reappraisal of naticid taxonomy based on an extensive database of shell morphological characters and identified many distinct family- and subfamily-specific characters that survived fossilization. This approach has enabled us to identify three new naticid species from the Late Jurassic horizons of Kutch, India, thus extending back the time of origin of the family Naticidae by 30 Ma.
Analysis of character matrix data reveals that the present species—Gyrodes mahalanobisi new species, Euspira jhuraensis new species, and Euspira lakhaparensis new species—belong to two subfamilies, Gyrodinae and Polinicinae. The occurrence of typical naticid drill holes on various coeval gastropod and bivalve taxa along with these body fossils provides strong supporting evidence for the naticid affinity of these forms.
Lung surfactant (LS), a thin layer of phospholipids and proteins inside the alveolus of the lung is the first biological barrier to inhaled nanoparticles (NPs). LS stabilizes and protects the alveolus during its continuous compression and expansion by fine-tuning the surface tension at the air-water interface. Previous modelling studies have reported the biophysical function of LS monolayer and its role, but many open questions regarding the consequences and interactions of airborne nano-sized particles with LS monolayer remain. In spite of gold nanoparticles (AuNPs) having a paramount role in biomedical applications, the understanding of the interactions between bare AuNPs (as pollutants) and LS monolayer components still unresolved. Continuous inhalation of NPs increases the possibility of lung ageing, reducing the normal lung functioning and promoting lung malfunction, and may induce serious lung diseases such as asthma, lung cancer, acute respiratory distress syndrome, and more. Different medical studies have shown that AuNPs can disrupt the routine lung functions of gold miners and promote respiratory diseases. In this work, coarse-grained molecular dynamics simulations are performed to gain an understanding of the interactions between bare AuNPs and LS monolayer components at the nanoscale. Different surface tensions of the monolayer are used to mimic the biological process of breathing (inhalation and exhalation). It is found that the NP affects the structure and packing of the lipids by disordering lipid tails. Overall, the analysed results suggest that bare AuNPs impede the normal biophysical function of the lung, a finding that has beneficial consequences to the potential development of treatments of various respiratory diseases.
Transport properties, performance, and durability of a proton exchange fuel cell (PEMFC) highly depend on microstructure and spatial distribution of components in the gas diffusion layer (GDL), microporous layer (MPL), and catalyst layers (CLs) of the fuel cell. Modeling of transport properties and understanding of these effects are challenging due to limited understanding of actual three-dimensional (3D) structure of the components, especially over a wide range of length scales. In this work, 3D imaging on multiple scales, namely electron tomography on a nanoscale, focused ion beam–scanning electron microscopy on a microscale, and 3D X-ray microscopy on a macroscale, was applied to obtain 3D reconstructions of the actual CL, MPL, and GDL microstructure. Direct numerical simulations on 3D data sets with an upscaling approach were applied to demonstrate the capability to simulate overall electrical conductivity of the system. Details of the process, challenges, and results are described.
Resin acid-enriched composition (RAC) mainly containing tall oil fatty acid with an active component of resin acid (RA) can improve the microbial population in the digestive system, change the microbial fermentation, and improve the feed conversion ratio. We investigated the effects of dietary supplementation of RAC on sow colostrum yield (CY), colostrum composition and gut microbiota. Tall oil fatty acid and RA are commonly termed RAC and CLA, pinolenic, abietic, dehydrobiotic acids are characteristic components of RAC. The experiment was conducted in three trials in three respective herds. Sows were fed with a control diet and the same diet supplemented with 5 g RAC/day per sow during the last week of gestation. The 16S ribosomal RNA gene sequencing technique was used to assess sows’ faecal microbiota populations at farrowing. Colostrum nutritional composition, acute phase proteins (APPs) and immunoglobulin (Ig) content were also assessed. Individual piglets were weighed at birth and 24 h after the birth of first piglets in order to calculate CY and later at 3 to 4 weeks to calculate average daily gain. The RAC-fed sows had significantly higher IgG levels (P<0.05) in all three herds but treatment did not influence colostrum IgA and IgM concentration. There were no significant differences in colostrum protein, lactose and fat content in sows of the two diet groups (P>0.05), but those fed RAC had higher levels of colostrum serum amyloid A. Colostrum yield was significantly higher in RAC-fed sows in herds 2 and 3 with heavier piglets between 3 and 4 weeks of age (P<0.05), but not in herd 1 (P>0.05). Resin acid-enriched composition supplementation significantly increased some beneficial and fermentative bacteria (Romboutsia and Clostridium sensu stricto) than the control diet (P<0.01) while some opportunistic pathogens (Barnesiella, Sporobacter, Intestinimonas and Campylobacter), including Proteobacteria, were suppressed. Therefore, RAC added to the sow diet at late pregnancy increases colostrum IgG, colostrum availability for neonate piglets, and seems to promote better maternal intestinal microbial sources.
Agriculture in the Central Himalayan Region depends on the availability of suitable germplasm as well as natural conditions. Due to extreme weather conditions, food and nutrition security is a major issue for communities inhabiting these remote and inaccessible areas. Millets are common crops grown in these areas. Foxtail millet (Setaria italica (L.) P. Beauv) is an important crop and forms a considerable part of the diet in this region. The aim of the present study was to explore, collect, conserve and evaluate the untapped genetic diversity of foxtail millet at the molecular level and discover variability in their nutritional traits. A total of 30 accessions having unique traits of agronomic importance were collected and molecular profiling was performed. A total of 63 alleles were generated with an average of 2.52 alleles per locus and average expected heterozygosity of 0.37 ± 0.231. Significant genetic variability was revealed through the genetic differentiation (Fst) and gene flow (Nm) values. Structure-based analysis divided whole germplasm into three sub-groups. Rich variability was found in nutritional traits such as dietary fibre in husked grains, carbohydrate, protein, lysine and thiamine content. The collected germplasm may be useful for developing nutritionally rich and agronomically beneficial varieties of foxtail millet and also designing strategies for utilization of unexploited genetic diversity for food and nutrition security in this and other similar agro-ecological regions.
Turritellid gastropods are important components of many Cretaceous–Recent fossil marine faunas worldwide. Their shell is morphologically simple, making homoplasy widespread and phylogenetic analysis difficult, but fossil and living species can be recognized based on shell characters. For many decades, it has been the consensus that the oldest definite representatives of Turritellidae are from the Lower Cretaceous, and that pre-Cretaceous forms are homeomorphs. Some morphological characters of the present turritelline species resemble those of mathildoids, but many diagnostic characters clearly separate these two groups. We here describe and/or redescribe—based on examination of more than 2600 near complete specimens—four species from the Upper Jurassic Dhosa Oolite Member of the Chari Formation in Kutch, western India, and demonstrate that they are members of Turritellidae, subfamily Turritellinae, on the basis of diagnostic characters including apical sculptural ontogeny (obtained from SEM study), spiral sculpture, and growth line patterns. The four species are in order of abundance, Turritella jadavpuriensis Mitra and Ghosh, 1979; Turritella amitava new species; Turritella jhuraensis Mitra and Ghosh, 1979, and Turritella dhosaensis new species. The turritelline assemblages occur only on the northeastern flank of the Jhura dome (23°24’47.57”N, 69°36’09.26”E). Age of the Dhosa Oolite has recently been confirmed based on multiple ammonite species. All these points indicate that these fossils are the oldest record of the family Turritellidae—by almost 30 million years—in the world.
Traumatic events are associated with increased risk of psychotic experiences, but it is unclear whether this association is explained by mental disorders prior to psychotic experience onset.
To investigate the associations between traumatic events and subsequent psychotic experience onset after adjusting for post-traumatic stress disorder and other mental disorders.
We assessed 29 traumatic event types and psychotic experiences from the World Mental Health surveys and examined the associations of traumatic events with subsequent psychotic experience onset with and without adjustments for mental disorders.
Respondents with any traumatic events had three times the odds of other respondents of subsequently developing psychotic experiences (OR=3.1, 95% CI 2.7–3.7), with variability in strength of association across traumatic event types. These associations persisted after adjustment for mental disorders.
Exposure to traumatic events predicts subsequent onset of psychotic experiences even after adjusting for comorbid mental disorders.
Psychotic experiences (PEs), including hallucination- and delusion-like experiences, are robustly associated with self-injurious thoughts and behaviours (SITB) in the general population. However, it remains unclear as to why there is an association. The purpose of this systematic review was to elucidate the role of other factors that influence the association between PEs and SITB and, in doing so, highlight potential mechanisms underlying the relationship. A search of electronic international databases was undertaken, including PubMed, PsycINFO and EMBASE, and eligible studies were grouped according to seven confounder categories: sociodemographics, mental disorders, alcohol and substance use, environmental, psychological, intervention and family history/genetic factors. The systematic search strategy identified 41 publications reporting on 1 39 427 participants from 16 different countries. In the majority of studies, where adjustment for other variables occurred, the association between PEs and SITB persisted, suggesting PEs have an independent role. Common mental disorders, psychological distress and negative environmental exposures explained a substantial amount of the variance and therefore need to be considered as potential underlying mechanisms. There was high variability in the variables adjusted for in these studies, and so the question still remains as to whether the association between PEs and self-harm/suicidality can be attributed (fully or in part) to confounding and mediating factors or directly causal mechanisms. Regardless of causality, the now extensive literature reporting an association between these two clinical phenomena supports the broad usefulness of PEs as an indicator of risk for SITB.
Artilleryweed is an annual or short-lived perennial weed that is becoming increasingly problematic in nurseries and landscapes in tropical and subtropical environments. Currently, no herbicide recommendations exist for management of artilleryweed. Objectives of this trial were to evaluate PRE and POST herbicides for efficacy on artilleryweed. All studies were conducted in Apopka, FL in a shaded greenhouse. Herbicides evaluated for POST control included diquat, dimethenamid-P, flumioxazin, glufosinate, glyphosate, indaziflam, oxadiazon, pelargonic acid, sulfentrazone and sulfosulfuron applied at their highest labelled rates to mature (10 to 12 cm height) artilleryweed. For PRE experiments, pots were overseeded with artilleryweed seed and treated with dimethenamid-P, indaziflam, isoxaben, oxadiazon, oxyfluorfen+prodiamine, oxyfluorfen+pendimethalin, pendimethalin, pendimethalin+dimethenamid-P, prodiamine, prodiamine+isoxaben, S-metolachlor, or trifluralin+isoxaben. When assessing both initial fresh weight and regrowth, flumioxazin and glufosinate provided the most consistent POST control when applied at the highest labelled rate, although regrowth did occur following application with glufosinate. All PRE herbicides evaluated provided over 90% control of artilleryweed with the exception of isoxaben and trifluralin+isoxaben. Results indicate that several effective options exist for artilleryweed management, but more effective control will likely be achieved when herbicides are applied PRE.
We investigate the supernova remnant (SNR) 3C 397 and its neighboring pulsar PSR J1906+0722 in high energy gamma rays by using nearly six years of archival data of Large Area Telescope on board Fermi Gamma Ray Space Telescope (Fermi-LAT). The off-pulse analysis of gamma-ray flux from the location of PSR J1906+0722 reveals an excess emission which is found to be very close to the radio location of 3C 397. Here, we present the preliminary results of this gamma-ray analysis of 3C 397 and PSR J1906+0722.
Although there is robust evidence linking childhood adversities (CAs) and an increased risk for psychotic experiences (PEs), little is known about whether these associations vary across the life-course and whether mental disorders that emerge prior to PEs explain these associations.
We assessed CAs, PEs and DSM-IV mental disorders in 23 998 adults in the WHO World Mental Health Surveys. Discrete-time survival analysis was used to investigate the associations between CAs and PEs, and the influence of mental disorders on these associations using multivariate logistic models.
Exposure to CAs was common, and those who experienced any CAs had increased odds of later PEs [odds ratio (OR) 2.3, 95% confidence interval (CI) 1.9–2.6]. CAs reflecting maladaptive family functioning (MFF), including abuse, neglect, and parent maladjustment, exhibited the strongest associations with PE onset in all life-course stages. Sexual abuse exhibited a strong association with PE onset during childhood (OR 8.5, 95% CI 3.6–20.2), whereas Other CA types were associated with PE onset in adolescence. Associations of other CAs with PEs disappeared in adolescence after adjustment for prior-onset mental disorders. The population attributable risk proportion (PARP) for PEs associated with all CAs was 31% (24% for MFF).
Exposure to CAs is associated with PE onset throughout the life-course, although sexual abuse is most strongly associated with childhood-onset PEs. The presence of mental disorders prior to the onset of PEs does not fully explain these associations. The large PARPs suggest that preventing CAs could lead to a meaningful reduction in PEs in the population.
Urinary tract infection (UTI) is common in children aged <5 years with diarrhoea, but little is known about risk factors, aetiology and outcome of such children. We aimed to evaluate these knowledge gaps of UTI in children aged <5 years with diarrhoea. We enrolled all children aged <5 years with diarrhoea admitted to Dhaka Hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh, between May 2011 and April 2013, who had history of fever (⩾38 °C) and obtained a urine sample for culture. Diarrhoea with UTI (confirmed by culture) constituted cases (n = 26) and those without UTI constituted controls (n = 78). Threefold controls were randomly selected. The case-fatality rate was comparable in cases and controls (4% vs. 1%, P = 0·439). Escherichia coli (69%) and Klebsiella (15%) were the most commonly isolated pathogens. Persistent diarrhoea, pneumonia and prior antibiotics use were identified as risk factors for UTI in logistic regression analysis (P < 0·05 for all). Thus, children with diarrhoea presenting with persistent diarrhoea, pneumonia, and prior antibiotic use should be investigated for UTI for their prompt management that may reduce morbidity.
The Proterozoic Sushina Hill Complex is the only agpaitic complex, reported from India and is characterized by a eudialyte-rinkite-bearing nepheline syenite. The complex is considered a ‘metamorphosed agpaitic complex'. This study describes the mineral assemblages formed during successive stages of evolution from magmatic to hydrothermal stages and low-temperature subsolidus re-equilibration assemblage. The primary-late magmatic assemblage is characterized by albite, orthoclase, unaltered nepheline, zoned diopside-hedenbergite, rinkite, late magmatic eudialyte and magnesio-arfvedsonite formed at ∼700°C with maximum aSiO2 of 0.60. In contrast, a deuteric assemblage (400-348°C) is represented by aegirine-jadeite-rich clinopyroxene, post-magmatic eudialyte, sodalite, analcime and the decomposition assemblages formed after eudialyte with decreasing aSiO2 (0.52-0.48). A further low-temperature subsolidus assemblage (≤250°C) represented by late-forming natrolite could be either related to regressive stages of metamorphism or a continuum of the subsolidus processes. Considering the P/T range of the greenschist - lower-amphibolite facies of metamorphism it is evident that the incorporation of a jadeite component within pyroxene is related to a subsolidus process between ∼400°C and 348°C in a silica deficient environment. We emphasize that the deuteric fluid itself acted as an agent of metamorphism and the decomposition assemblage formed after eudialyte is retained even after metamorphism due to the convergence of subsolidus and metamorphic domains. The formation of jadeite-rich aegirine is not considered to result from metamorphism. Overall it is near-impossible to discern any bona fide metamorphic textures or mineral assemblages in these syenites which appear to preserve a relict mineralogy regardless of their occurrence in country rocks which have experienced greenschist - amphibolite facies metamorphism. The Sushina complex is very similar in this respect to the Norra Kärr complex (Sweden).
Quasi-one-dimensional (quasi-1D) tools developed for capturing flow and acoustic dynamics in non-segmented solid rocket motors are evaluated using multi-dimensional computational fluid dynamic simulations and used to characterise damping of modal perturbations. For motors with high length-to-diameter ratios (of the order of 10), remarkably accurate estimates of frequencies and damping rates of lower modes can be obtained using the the quasi-1D approximation. Various grain configurations are considered to study the effect of internal geometry on damping rates. Analysis shows that lower cross-sectional area at the nozzle entry plane is found to increase damping rates of all the modes. The flow-turning loss for a mode increases if the more mass addition due to combustion is added at pressure nodes. For the fundamental mode, this loss is, therefore, maximum if burning area is maximum at the centre. The insights from this study in addition to recommendations made by Blomshield(1) based on combustion considerations would be very helpful in realizing rocket motors free from combustion instability.
Background: Cognitive dysfunction following coronary artery bypass surgery is a regular occurrence, but its cause is still unknown. In order to devise strategies to mitigate this acquired disability, a precise and quantitative description of the post-operative neurocognitive phenotype is necessary. This study is designed to assess the feasibility of using the KINARM robot to quantify the changes in the neurological function after cardaic surgery. Methods: Patients without prior history of cognitive dysfunction were recruited from the pre-operative cardiac surgery clinic, and underwent pre-operative assessment with the KINARM. The KINARM provides a quantitative assessment of the neurocognitive control of the upper limbs. During bypass surgery, brain tissue oxygen levels were measured with near-infrared spectroscopy. Patients were reassessed with the KINARM post-operatively at 3 months. Results: To date, 12 participants have been recruited (mean age = 65 years, all male). On straightforward tasks, such as visually guided reaching, the majority of patients scored within the normal range, both pre- and post-operatively. In more complex tasks, required visuospatial and executive functioning, post-operative deficits were more pronounced. Conclusions: It is feasible to use the KINARM robot to provide a quantitative measurement of the neurocognitive phenotype of patients after cardiac surgery.
Investigation of stellar spectra has been active during the last four years. Without attempting to make a complete survey, some important researches may be mentioned.
The theory of the intensities and contours of absorption lines has been discussed by Eddington, Milne, Pannekoek, Woolley, H. H. Plaskett, and others, and has proved to be difficult. For example, no quantitative theory has yet been developed for the residuai intensity which remains in even the strongest lines, although the physical causes underlying the formation of residual intensities are rather obvious. Study of solar lines with light which has left the surface at different angles shows that the processes which produce the wings and the centre are probably different. The most promising line of attack on this intricate problem appears to be in studies of the solar spectrum, where different regions of the disc may be separately investigated, rather than of integrated starlight. The highest dispersion available, even in solar work, will be none too great.
A comprehensive study based on U–Pb and Hf isotope analyses of zircons from gneisses has been conducted along the western part (Babina area) of the E–W-trending Bundelkhand Tectonic Zone in the central part of the Archaean Bundelkhand Craton. 207Pb–206Pb zircon ages and Hf isotopic data indicate the existence of a felsic crust at ~ 3.59 Ga, followed by a second tectonothermal event at ~ 3.44 Ga, leading to calc-alkaline magmatism and subsequent crustal growth. The study hence suggests that crust formation in the Bundelkhand Craton occurred in a similar time-frame to that recorded from the Singhbhum and Bastar cratons of the North Indian Shield.