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Weed management is a major challenge in organic crop production, and organic farms generally harbor larger weed populations and more diverse communities compared with conventional farms. However, little research has been conducted on the effects of different organic management practices on weed communities and crop yields. In 2014 and 2015, we measured weed community structure and soybean [Glycine max (L.) Merr.] yield in a long-term experiment that compared four organic cropping systems that differed in nutrient inputs, tillage, and weed management intensity: (1) high fertility (HF), (2) low fertility (LF), (3) enhanced weed management (EWM), and (4) reduced tillage (RT). In addition, we created weed-free subplots within each system to assess the impact of weeds on soybean yield. Weed density was greater in the LF and RT systems compared with the EWM system, but weed biomass did not differ among systems. Weed species richness was greater in the RT system compared with the EWM system, and weed community composition differed between RT and other systems. Our results show that differences in weed community structure were primarily related to differences in tillage intensity, rather than nutrient inputs. Soybean yield was lower in the EWM system compared with the HF and RT systems. When averaged across all four cropping systems and both years, soybean yield in weed-free subplots was 10% greater than soybean yield in the ambient weed subplots that received standard management practices for the systems in which they were located. Although weed competition limited soybean yield across all systems, the EWM system, which had the lowest weed density, also had the lowest soybean yield. Future research should aim to overcome such trade-offs between weed control and yield potential, while conserving weed species richness and the ecosystem services associated with increased weed diversity.
Evidence has been accumulating regarding alterations in components of the endocannabinoid system in patients with psychosis. Of all the putative risk factors associated with psychosis, being at clinical high-risk for psychosis (CHR) has the strongest association with the onset of psychosis, and exposure to childhood trauma has been linked to an increased risk of development of psychotic disorder. We aimed to investigate whether being at-risk for psychosis and exposure to childhood trauma were associated with altered endocannabinoid levels.
We compared 33 CHR participants with 58 healthy controls (HC) and collected information about previous exposure to childhood trauma as well as plasma samples to analyse endocannabinoid levels.
Individuals with both CHR and experience of childhood trauma had higher N-palmitoylethanolamine (p < 0.001) and anandamide (p < 0.001) levels in peripheral blood compared to HC and those with no childhood trauma. There was also a significant correlation between N-palmitoylethanolamine levels and symptoms as well as childhood trauma.
Our results suggest an association between CHR and/or childhood maltreatment and elevated endocannabinoid levels in peripheral blood, with a greater alteration in those with both CHR status and history of childhood maltreatment compared to those with either of those risks alone. Furthermore, endocannabinoid levels increased linearly with the number of risk factors and elevated endocannabinoid levels correlated with the severity of CHR symptoms and extent of childhood maltreatment. Further studies in larger cohorts, employing longitudinal designs are needed to confirm these findings and delineate the precise role of endocannabinoid alterations in the pathophysiology of psychosis.
Cognitive-behavioural therapy (CBT) is an effective treatment for depressed adults. CBT interventions are complex, as they include multiple content components and can be delivered in different ways. We compared the effectiveness of different types of therapy, different components and combinations of components and aspects of delivery used in CBT interventions for adult depression. We conducted a systematic review of randomised controlled trials in adults with a primary diagnosis of depression, which included a CBT intervention. Outcomes were pooled using a component-level network meta-analysis. Our primary analysis classified interventions according to the type of therapy and delivery mode. We also fitted more advanced models to examine the effectiveness of each content component or combination of components. We included 91 studies and found strong evidence that CBT interventions yielded a larger short-term decrease in depression scores compared to treatment-as-usual, with a standardised difference in mean change of −1.11 (95% credible interval −1.62 to −0.60) for face-to-face CBT, −1.06 (−2.05 to −0.08) for hybrid CBT, and −0.59 (−1.20 to 0.02) for multimedia CBT, whereas wait list control showed a detrimental effect of 0.72 (0.09 to 1.35). We found no evidence of specific effects of any content components or combinations of components. Technology is increasingly used in the context of CBT interventions for depression. Multimedia and hybrid CBT might be as effective as face-to-face CBT, although results need to be interpreted cautiously. The effectiveness of specific combinations of content components and delivery formats remain unclear. Wait list controls should be avoided if possible.
Janis McLarren Caldwell compares Charlotte Brontë’s writing about experiences of imaginative transport (in the Roe Head Journal, which sustained engagement with the Angria of her earlier juvenilia, and in Jane Eyre) with Victorian scientific writing about the imagination. The work of early psychologists increasingly described creative imagination not as Romantic transcendence, but as a function of the automatic mind. For Caldwell, the discontinuity experienced by Brontë between creative unconscious and conscious states may be related to her frequent mature pattern of presenting Romantic interludes only to ironise or deflate them. Caldwell shows how Brontë’s early writings reserved her most exalted language for the experiences of imagining. Drawing upon Elaine Scarry’s notion of vivacity, Caldwell explores how Brontë’s work is placed in relation to pictorialist accounts of mental imaging. Charlotte Brontë, while influenced by materialist thought, rejected the wholesale erasure of the soul. While Brontë was attuned to ideas about embodiment and scientific accounts of the mind, she also employed a Scriptural language of body and soul. As Caldwell’s chapter shows, Charlotte Brontë’s introspective accounts of creativity are valuable for our contemporary neurological understandings of verbal and visual cognition, and continued Western philosophical investigations of the mind/body problem.
Wearable devices are fast evolving to address mobility and autonomy needs of elderly people who would benefit from physical assistance. Recent developments in soft robotics provide important opportunities to develop soft exoskeletons (also called exosuits) to enable both physical assistance and improved usability and acceptance for users. The XoSoft EU project has developed a modular soft lower limb exoskeleton to assist people with low mobility impairments. In this paper, we present the design of a soft modular lower limb exoskeleton to improve person’s mobility, contributing to independence and enhancing quality of life. The novelty of this work is the integration of quasi-passive elements in a soft exoskeleton. The exoskeleton provides mechanical assistance for subjects with low mobility impairments reducing energy requirements between 10% and 20%. Investigation of different control strategies based on gait segmentation and actuation elements is presented. A first hip–knee unilateral prototype is described, developed, and its performance assessed on a post-stroke patient for straight walking. The study presents an analysis of the human–exoskeleton energy patterns by way of the task-based biological power generation. The resultant assistance, in terms of power, was 10.9% ± 2.2% for hip actuation and 9.3% ± 3.5% for knee actuation. The control strategy improved the gait and postural patterns by increasing joint angles and foot clearance at specific phases of the walking cycle.
This article analyzes divorce as a technology of governance in twentieth-century America in order to examine the emergence of a rights-based liberal welfare-state regime during the postwar era. The author offers an interpretation of the post–World War II “divorce boom” that challenges prevailing notions of postwar domestic tranquillity and highlights the legal formalization of family relations and the administration of the developing welfare state. The article posits an important shift in postwar public policy regarding divorce from the policing of public morality through family preservation to the regulation of public welfare through family structures. The legal consequences of this shift are explored at the local level by focusing on the “problem” of the Chicago divorce courts and the frustrated attempts of postwar reformers in Illinois to employ the traditional methods and rhetoric of Progressive Era reform. At the national level, the author examines the formulation of new governmental objectives and individual rights in the liberal welfare-state regime through an analysis of the United States Supreme Court's decisions regarding migratory divorce.
Much work has been done in the investigation of the properties of solutions of linear elliptic systems of partial differential equations. Among these systems, the class of Beltrami systems has been studied for many years and has been shown to be of fundamental importance. Another class, perhaps of equal importance, is the class defined by Bers (1), which the author has taken the liberty of calling Bers systems. Solutions of these systems will be called Beltrami and Bers functions respectively.
Hyperbolic polariton modes are highly appealing for a broad range of applications in nanophotonics, including surfaced enhanced sensing, sub-diffractional imaging, and reconfigurable metasurfaces. Here we show that attenuated total reflectance (ATR) micro-spectroscopy using standard spectroscopic tools can launch hyperbolic polaritons in a Kretschmann–Raether configuration. We measure multiple hyperbolic and dielectric modes within the naturally hyperbolic material hexagonal boron nitride as a function of different isotopic enrichments and flake thickness. This overcomes the technical challenges of measurement approaches based on nanostructuring, or scattering scanning near-field optical microscopy. Ultimately, our ATR approach allows us to compare the optical properties of small-scale materials prepared by different techniques systematically.
Most previous research on changes in weed abundance and community composition in cropping systems has focused on field crops. The study presented here examined changes in the weed seedbank and aboveground biomass in four organic vegetable cropping systems over a 10-yr period. The systems included an Intensive system with six crops per 4-yr rotation, an Intermediate system with one cash crop per year, a Bio-extensive system with alternating cash crop and tilled fallow years plus prevention of seed rain, and a Ridge-tillage system with one cash crop per year. Systems also differed in the types and number of cover crops between cash crops. During the course of the experiment, the weed community shifted from one dominated by summer annual broadleaf species that reproduce at the end of their lives to a community dominated by summer and winter annuals that mature rapidly. This shift in community composition can be attributed to the change in land use from conventionally managed corn (Zea mays L.) and alfalfa (Medicago sativa L.) to organic vegetable production. In particular, crop rotations with diverse preplantings and postharvest tillage dates interrupted the life cycle of common lambsquarters (Chenopodium album L.) and pigweed species (Amaranthus spp.: mostly Powell amaranth [Amaranthus powellii S. Watson], with small numbers of redroot pigweed [Amaranthus retroflexus L.] and smooth pigweed [Amaranthus hybridus L.]), while favoring a diverse assemblage of quickly maturing species. The study thus demonstrates that an appropriate crop rotation can control the seedbank of weeds like C. album that potentially persist well in the soil. The Ridge-tillage system greatly reduced the frequency and depth of tillage relative to other systems while effectively suppressing perennial weeds. The early-reproducing annuals, however, became more abundant in the Ridge-tillage system than in the other systems, primarily due to escapes along the edge of the scraped ridges. The tilled fallow periods coupled with prevention of seed rain in the Bio-extensive system substantially reduced weed abundance through time and relative to the other systems.
The application of behavioural insights to public policy has been a success story of recent years, in academia and in the civil service. Alongside this, a parallel group of practitioners has emerged, using the same underlying research to pursue commercial and marketing goals. Although the objectives are mostly different, many of the approaches are similar. This article contrasts public and private sector approaches and highlights lessons each group can learn from the other.
Rapid identification of esophageal intubations is critical to avoid patient morbidity and mortality. Continuous waveform capnography remains the gold standard for endotracheal tube (ETT) confirmation, but it has limitations. Point-of-care ultrasound (POCUS) may be a useful alternative for confirming ETT placement. The objective of this study was to determine the accuracy of paramedic-performed POCUS identification of esophageal intubations with and without ETT manipulation.
A prospective, observational study using a cadaver model was conducted. Local paramedics were recruited as subjects and each completed a survey of their demographics, employment history, intubation experience, and prior POCUS training. Subjects participated in a didactic session in which they learned POCUS identification of ETT location. During each study session, investigators randomly placed an ETT in either the trachea or esophagus of four cadavers, confirmed with direct laryngoscopy. Subjects then attempted to determine position using POCUS both without and with manipulation of the ETT. Manipulation of the tube was performed by twisting the tube. Descriptive statistics and logistic regression were used to assess the results and the effects of previous paramedic experience.
During 12 study sessions, from March 2014 through December 2015, 57 subjects participated, evaluating a total of 228 intubations: 113 tracheal and 115 esophageal. Subjects were 84.0% male, mean age of 39 years (range: 22 - 62 years), with median experience of seven years (range: 0.6 - 39 years). Paramedics correctly identified ETT location in 158 (69.3%) cases without and 194 (85.1%) with ETT manipulation. The sensitivity and specificity of identifying esophageal location without ETT manipulation increased from 52.2% (95% confidence interval [CI], 43.0-61.0) and 86.7% (95% CI, 81.0-93.0) to 87.0% (95% CI, 81.0-93.0) and 83.2% (95% CI, 0.76-0.90) after manipulation (P<.0001), without affecting specificity (P=.45). Subjects correctly identified 41 previously incorrectly identified esophageal intubations. Paramedic experience, previous intubations, and POCUS experience did not correlate with ability to identify tube location.
Paramedics can accurately identify esophageal intubations with POCUS, and manipulation improves identification. Further studies of paramedic use of dynamic POCUS to identify inadvertent esophageal intubations are needed.
LemaPC, O’BrienM, WilsonJ, St. JamesE, LindstromH, DeAngelisJ, CaldwellJ, MayP, ClemencyB.Avoid the Goose! Paramedic Identification of Esophageal Intubation by Ultrasound. Prehosp Disaster Med.2018;33(4):406–410