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The past 50 yr of advances in weed recognition technologies have poised site-specific weed control (SSWC) on the cusp of requisite performance for large-scale production systems. The technology offers improved management of diverse weed morphology over highly variable background environments. SSWC enables the use of nonselective weed control options, such as lasers and electrical weeding, as feasible in-crop selective alternatives to herbicides by targeting individual weeds. This review looks at the progress made over this half-century of research and its implications for future weed recognition and control efforts; summarizing advances in computer vision techniques and the most recent deep convolutional neural network (CNN) approaches to weed recognition. The first use of CNNs for plant identification in 2015 began an era of rapid improvement in algorithm performance on larger and more diverse datasets. These performance gains and subsequent research have shown that the variability of large-scale cropping systems is best managed by deep learning for in-crop weed recognition. The benefits of deep learning and improved accessibility to open-source software and hardware tools has been evident in the adoption of these tools by weed researchers and the increased popularity of CNN-based weed recognition research. The field of machine learning holds substantial promise for weed control, especially the implementation of truly integrated weed management strategies. Whereas previous approaches sought to reduce environmental variability or manage it with advanced algorithms, research in deep learning architectures suggests that large-scale, multi-modal approaches are the future for weed recognition.
To overcome grass supply shortages on the main grazing block, some pasture-based dairy farmers are using zero-grazing (also known as ‘cut and carry’), whereby cows are periodically housed and fed fresh grass harvested from external land blocks. To determine the effect of zero-grazing on cow performance, two early-lactation experiments were conducted with autumn and spring-calving dairy cows. Cows were assigned to one of two treatments in a randomized complete block design. The two treatments were zero-grazing (ZG) and grazing (G). The ZG group were housed and fed zero-grazed grass, while the G group grazed outdoors at pasture. Both treatments were fed perennial ryegrass (Lolium perenne L.) from the same paddock. In experiment 1, 24 Holstein Friesian cows (n = 12) were studied over a 35-day experimental period in autumn and offered fresh grass, grass silage, ground maize and concentrates. In experiment 2, 30 Holstein Friesian cows (n = 15) were studied over a 42-day experimental period and offered fresh grass and concentrates. Average dry matter intake and milk yield was similar for ZG and G in both experiments. Likewise, ZG did not have an effect on milk composition, body condition or locomotion. Zero-grazing had no effect on total nitrogen excretion or nitrogen utilization efficiency in either experiment, or on rumen pH and ammonia concentration in experiment 1. While zero-grazing may enable farmers to supply fresh grass to early-lactation cows in spring and autumn, results from this study suggest that there are no additional benefits to cow performance in comparison to well-managed grazed grass.
Italian ryegrass is a major weed in winter cereals in the south-central United States. Harvest weed seed control (HWSC) tactics that aim to remove weed seed from crop fields are a potential avenue to reduce Italian ryegrass seedbank inputs. To this effect, a 4-yr, large-plot field study was conducted in College Station, Texas, and Newport, Arkansas, from 2016 to 2019. The treatments were arranged in a split-plot design. The main-plot treatments were (1) no narrow-windrow burning (a HWSC strategy) + disk tillage immediately after harvest, (2) HWSC + disk tillage immediately after harvest, and (3) HWSC + disk tillage 1 mo after harvest. The subplot treatments were (1) pendimethalin (1,065 g ai ha−1; Prowl H2O®) as a delayed preemergence application (herbicide program #1), and (2) a premix of flufenacet (305 g ai ha−1) + metribuzin (76 g ai ha−1; Axiom®) mixed with pyroxasulfone (89 g ai ha−1; Zidua® WG) as an early postemergence application followed by pinoxaden (59 g ai ha−1; Axial® XL) in spring (herbicide program #2). After 4 yr, HWSC alone was significantly better than no HWSC. Herbicide program #2 was superior to herbicide program #1. Herbicide program #2 combined with HWSC was the most effective treatment. The combination of herbicide program #1 and standard harvest practice (no HWSC; check) led to an increase in fall Italian ryegrass densities from 4 plants m−2 in 2017 to 58 plants m−2 in 2019 at College Station. At wheat harvest, Italian ryegrass densities were 58 and 59 shoots m−2 in check plots at College Station and Newport, respectively, whereas the densities were near zero in plots with herbicide program #2 and HWSC at both locations. These results will be useful for developing an improved Italian ryegrass management strategy in this region.
Caregivers of patients with cancer are at significant risk for existential distress. Such distress negatively impacts caregivers’ quality of life and capacity to serve in their role as healthcare proxies, and ultimately, contributes to poor bereavement outcomes. Our team developed Meaning-Centered Psychotherapy for Cancer Caregivers (MCP-C), the first targeted psychosocial intervention that directly addresses existential distress in caregivers.
Method
Nine caregivers of patients with glioblastoma multiforme (GBM) enrolled in a pilot randomized controlled trial evaluating the feasibility, acceptability, and effects of MCP-C, and completed in-depth interviews about their experience in the therapy. One focus group with three MCP-C interventionists was also completed.
Results
Four key themes emerged from interviews: (1) MCP-C validated caregivers’ experience of caregiving; (2) MCP-C helped participants reframe their “caregiving identity” as a facet of their larger self-identity, by placing caregiving in the context of their life's journey; (3) MCP-C enabled caregivers to find ways to assert their agency through caregiving; and (4) the structure and sequence of sessions made MCP-C accessible and feasible. Feedback from interventionists highlighted several potential manual changes and overall ways in which MCP-C can help facilitate caregivers’ openness to discussing death and engaging in advanced care planning discussions with the patient.
Significance of results
The overarching goal of MCP-C is to allow caregivers to concurrently experience meaning and suffering; the intervention does not seek to deny the reality of challenges endured by caregivers, but instead to foster a connection to meaning and purpose alongside their suffering. Through in-depth interviews with caregivers and a focus group with MCP interventionists, we have refined and improved our MCP-C manual so that it can most effectively assist caregivers in experiencing meaning and purpose, despite inevitable suffering.
Burnout, anxiety and depression are commonly reported among surgical residents and faculty members. Resident training programmes are encouraged to implement structured wellness initiatives, to address emotional stress.
Methods
Thirty otolaryngology residents and faculty members were invited to participate in this prospective pilot trial. Participants were randomised to either the intervention group, which involved completing 10 mobile meditation sessions, or the control group. Outcomes were measured with the Generalized Anxiety Disorder scale-7, Patient Health Questionnaire and Professional Quality of Life scale.
Results
Nineteen participants completed the study. Participants in the intervention group had a significantly greater mean change in Generalized Anxiety Disorder scale-7 score (−2.7 ± 3.335 vs 0.33 ± 1.225; p = 0.04). There was no significant difference in average change in Patient Health Questionnaire-9 scores or Professional Quality of Life scale sub-scores between the intervention and control groups.
Conclusion
Short meditation sessions can significantly improve anxiety in surgical residents and faculty members, and they offer a simple, attainable and effective wellness intervention.
The purpose of this article was to determine the impact of employing a telephone clinic for follow-up of patients with stable lateral skull-base tumours.
Method
An analysis of 1515 patients in the national lateral skull-base service was performed, and 148 patients enrolled in the telephone clinic to date were identified. The length of time that patients waited for results of their follow-up scans and the travel distance saved by patients not having to attend the hospital for their results was determined.
Results
The mean time from scan to receiving results was 30.5 ± 32 days, 14 days sooner than in the face-to-face group (p = 0.0016). The average round-trip distance travelled by patients to the hospital for results of their scans was 256 ± 131 km.
Conclusion
The telephone clinic led to a significant reduction in time until patients received their scan results and helped reduce travel distance and clinic numbers in traditional face-to-face clinics.
The Late Triassic fauna of the Lossiemouth Sandstone Formation (LSF) from the Elgin area, Scotland, has been pivotal in expanding our understanding of Triassic terrestrial tetrapods. Frustratingly, due to their odd preservation, interpretations of the Elgin Triassic specimens have relied on destructive moulding techniques, which only provide incomplete, and potentially distorted, information. Here, we show that micro-computed tomography (μCT) could revitalise the study of this important assemblage. We describe a long-neglected specimen that was originally identified as a pseudosuchian archosaur, Ornithosuchus woodwardi. μCT scans revealed dozens of bones belonging to at least two taxa: a small-bodied pseudosuchian and a specimen of the procolophonid Leptopleuron lacertinum. The pseudosuchian skeleton possesses a combination of characters that are unique to the clade Erpetosuchidae. As a basis for investigating the phylogenetic relationships of this new specimen, we reviewed the anatomy, taxonomy and systematics of other erpetosuchid specimens from the LSF (all previously referred to Erpetosuchus). Unfortunately, due to the differing representation of the skeleton in the available Erpetosuchus specimens, we cannot determine whether the erpetosuchid specimen we describe here belongs to Erpetosuchus granti (to which we show it is closely related) or if it represents a distinct new taxon. Nevertheless, our results shed light on rarely preserved details of erpetosuchid anatomy. Finally, the unanticipated new information extracted from both previously studied and neglected specimens suggests that fossil remains may be much more widely distributed in the Elgin quarries than previously recognised, and that the richness of the LSF might have been underestimated.
Recent technological advances have led to a novel class of microfluidic devices which can be rapidly fabricated by printing a fluid onto a solid substrate with flows generated passively via surface tension. The nonlinear dependence between flow and the heights of the conduits, however, prevent straightforward calculation of the resulting dynamics. In this paper we use matched asymptotic expansions to predict how flow through these devices can be tuned by changing their geometry. We begin with the simple ‘dumbbell’ configuration in which two fluid drops with different sizes are connected by a long, thin and narrow conduit. We calculate the time scale required for one drop to drain into the other and how this depends both on the geometry of the pinned contact line and volume of fluid deposited into the drops. Our model therefore provides the mechanistic basis to design conduits with a particular fluid flux and/or shear stress, which are often key experimental constraints. Our asymptotic predictions are shown to be in excellent agreement with numerical simulations even for moderate aspect ratios (the ratio of conduit width to length). Next, we show how our results for the simple dumbbell configuration can be extended to predict the flow through networks of conduits with multiple drops and nodes, and hence may assist in their design and implementation. This new mathematical framework has the potential to increase the use of surface tension driven microfluidics across a wide range of disciplines as it allows alternate designs to be rapidly assessed.
Results of a co-morbid insomnia and depression study of eszopiclone and fluoxetine demonstrated that co-therapy produced greater improvements in sleep and depression than fluoxetine monotherapy. To determine if changes in the HAMD17 were due to sleep, individual HAMD17 items were evaluated.
Methods:
Patients met DSM-IV criteria for MDD and insomnia, with screening HAMD17 >14. All patients received fluoxetine QAM for 10 weeks, and randomly received double-blind eszopiclone 3mg or placebo QHS for 8 weeks, followed by a single-blind placebo 2-week run-out. HAMD17 was completed at Weeks 4, 8, and 10. Individual items were compared with ANCOVA using an LOCF approach.
Results:
Mean baseline HAMD17 scores were 22 for each group. At Week 4, differences were noted between treatment groups in the total score, and the individual items of insight, the three insomnia items (p<0.02 vs monotherapy), with a trend for guilt (p=0.07). At Week 8, significant differences between groups were noted in total score (p=0.0005), in the clinician-administered Bech subscale (p<0.001), in the three insomnia items (p<0.001), guilt, work/activities, and anxiety psychic (p<0.05). At Week 10, the total score, guilt, the three insomnia items, work/activities, retardation, agitation, anxiety psychic, general somatic symptoms, and hypochondriasis demonstrated significant improvements (p<0.05 vs monotherapy) despite discontinuation of eszopiclone.
Conclusions:
Eszopiclone/fluoxetine co-therapy resulted in significant improvements in the insomnia items of the HAMD17. In addition, several items related to core depressive symptoms were also improved with co-therapy compared with monotherapy.
The aim of the study was to assess the experiences of discrimination as reported by people with mental health problems and to explore the impact of hospitalisation.
Methods
306 people with mental health problems provided sociodemographic data and data on discrimination using the discrimination and stigma scale version 12 (DISC-12) with the domains negative experienced discrimination, anticipated discrimination, overcoming stigma and discrimination, and positive experienced discrimination. Logistic regression analysis was used to test the impact of hospitalisation on discrimination, controlled for age, gender, education, employment, diagnosis and having been prescribed medication.
Results
Hospitalisation had a major impact on negative discrimination: People were more likely to be treated unfairly in making or keeping friends, in marriage or divorce, by people in their neighbourhood, in social life, by mental health staff and in terms of privacy, if they had been hospitalised. They were also more likely to be avoided or shunned by people who knew about the mental health problem. People with a history of hospitalisation also reported more anticipated discrimination: They had stopped themselves more often from having a close personal relationship and concealed their mental health problem from others more often than those without a history of hospitalisation. However, people who had been hospitalised also experienced more positive discrimination in terms of being treated more positively in getting welfare benefits or disability pensions and in housing.
Conclusion
Findings suggest that treatment in hospital contributed to a higher extent to experienced discrimination than treatment in the community.
We sought to explore whether obstetric complications (OCs) are more likely to occur in the presence of familial/genetic susceptibility for schizophrenia or whether they themselves represent an independent environmental risk factor for schizophrenia.
Methods
The presence of OCs was assessed through maternal interview on 216 subjects, comprising 36 patients with schizophrenia from multiply affected families, 38 of their unaffected siblings, 31 schizophrenic patients with no family history of psychosis, 51 of their unaffected siblings and 60 normal comparison subjects. We examined the familiality of OCs and whether OCs were commoner in the patient and sibling groups than in the control group.
Results
OCs tended to cluster within families, especially in multiply affected families. Patients with schizophrenia, especially those from multiply affected families, had a significantly higher rate of OCs compared to normal comparison subjects, but there was no evidence for an elevated rate of OCs in unaffected siblings.
Conclusion
Our data provides little evidence for a link between OCs and genetic susceptibility to schizophrenia. If high rates of OCs are related to schizophrenia genes, this relationship is weak and will only be detected by very large sample sizes.
Little is known about who would benefit from Internet-based personalised nutrition (PN) interventions. This study aimed to evaluate the characteristics of participants who achieved greatest improvements (i.e. benefit) in diet, adiposity and biomarkers following an Internet-based PN intervention. Adults (n 1607) from seven European countries were recruited into a 6-month, randomised controlled trial (Food4Me) and randomised to receive conventional dietary advice (control) or PN advice. Information on dietary intake, adiposity, physical activity (PA), blood biomarkers and participant characteristics was collected at baseline and month 6. Benefit from the intervention was defined as ≥5 % change in the primary outcome (Healthy Eating Index) and secondary outcomes (waist circumference and BMI, PA, sedentary time and plasma concentrations of cholesterol, carotenoids and omega-3 index) at month 6. For our primary outcome, benefit from the intervention was greater in older participants, women and participants with lower HEI scores at baseline. Benefit was greater for individuals reporting greater self-efficacy for ‘sticking to healthful foods’ and who ‘felt weird if [they] didn’t eat healthily’. Participants benefited more if they reported wanting to improve their health and well-being. The characteristics of individuals benefiting did not differ by other demographic, health-related, anthropometric or genotypic characteristics. Findings were similar for secondary outcomes. These findings have implications for the design of more effective future PN intervention studies and for tailored nutritional advice in public health and clinical settings.
The widespread use of herbicides in cropping systems has led to the evolution of resistance in major weeds. The resultant loss of herbicide efficacy is compounded by a lack of new herbicide sites of action, driving demand for alternative weed control technologies. While there are many alternative methods for control, identifying the most appropriate method to pursue for commercial development has been hampered by the inability to compare techniques in a fair and equitable manner. Given that all currently available and alternative weed control methods share an intrinsic energy consumption, the aim of this review was to compare methods based on energy consumption. Energy consumption was compared for chemical, mechanical, and thermal weed control technologies when applied as broadcast (whole-field) and site-specific treatments. Tillage systems, such as flex-tine harrow (4.2 to 5.5 MJ ha−1), sweep cultivator (13 to 14 MJ ha−1), and rotary hoe (12 to 17 MJ ha−1) consumed the least energy of broadcast weed control treatments. Thermal-based approaches, including flaming (1,008 to 4,334 MJ ha−1) and infrared (2,000 to 3,887 MJ ha−1), are more appropriate for use in conservation cropping systems; however, their energy requirements are 100- to 1,000-fold greater than those of tillage treatments. The site-specific application of weed control treatments to control 2-leaf-stage broadleaf weeds at a density of 5 plants m−2 reduced energy consumption of herbicidal, thermal, and mechanical treatments by 97%, 99%, and 97%, respectively. Significantly, this site-specific approach resulted in similar energy requirements for current and alternative technologies (e.g., electrocution [15 to 19 MJ ha−1], laser pyrolysis [15 to 249 MJ ha−1], hoeing [17 MJ ha−1], and herbicides [15 MJ ha−1]). Using similar energy sources, a standardized energy comparison provides an opportunity for estimation of weed control costs, suggesting site-specific weed management is critical in the economically realistic implementation of alternative technologies.