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The onset of magnetic reconnection in space, astrophysical and laboratory plasmas is reviewed discussing results from theory, numerical simulations and observations. After a brief introduction on magnetic reconnection and approach to the question of onset, we first discuss recent theoretical models and numerical simulations, followed by observations of reconnection and its effects in space and astrophysical plasmas from satellites and ground-based detectors, as well as measurements of reconnection in laboratory plasma experiments. Mechanisms allowing reconnection spanning from collisional resistivity to kinetic effects as well as partial ionization are described, providing a description valid over a wide range of plasma parameters, and therefore applicable in principle to many different astrophysical and laboratory environments. Finally, we summarize the implications of reconnection onset physics for plasma dynamics throughout the Universe and illustrate how capturing the dynamics correctly is important to understanding particle acceleration. The goal of this review is to give a view on the present status of this topic and future interesting investigations, offering a unified approach.
Potential effectiveness of harvest weed seed control (HWSC) systems depends upon seed shatter of the target weed species at crop maturity, enabling its collection and processing at crop harvest. However, seed retention likely is influenced by agroecological and environmental factors. In 2016 and 2017, we assessed seed shatter phenology in thirteen economically important broadleaf weed species in soybean [Glycine max (L.) Merr.] from crop physiological maturity to four weeks after physiological maturity at multiple sites spread across fourteen states in the southern, northern, and mid-Atlantic U.S. Greater proportions of seeds were retained by weeds in southern latitudes and shatter rate increased at northern latitudes. Amaranthus species seed shatter was low (0 to 2%), whereas shatter varied widely in common ragweed (Ambrosia artemisiifolia L.) (2 to 90%) over the weeks following soybean physiological maturity. Overall, the broadleaf species studied shattered less than ten percent of their seeds by soybean harvest. Our results suggest that some of the broadleaf species with greater seed retention rates in the weeks following soybean physiological maturity may be good candidates for HWSC.
Seed shatter is an important weediness trait on which the efficacy of harvest weed seed control (HWSC) depends. The level of seed shatter in a species is likely influenced by agroecological and environmental factors. In 2016 and 2017, we assessed seed shatter of eight economically important grass weed species in soybean [Glycine max (L.) Merr.] from crop physiological maturity to four weeks after maturity at multiple sites spread across eleven states in the southern, northern, and mid-Atlantic U.S. From soybean maturity to four weeks after maturity, cumulative percent seed shatter was lowest in the southern U.S. regions and increased as the states moved further north. At soybean maturity, the percent of seed shatter ranged from 1 to 70%. That range had shifted to 5 to 100% (mean: 42%) by 25 days after soybean maturity. There were considerable differences in seed shatter onset and rate of progression between sites and years in some species that could impact their susceptibility to HWSC. Our results suggest that many summer annual grass species are likely not ideal candidates for HWSC, although HWSC could substantially reduce their seed output at during certain years.
To detect eating disorders and risky eating behaviour in early stages, screening tests are used. In order to examine as many adolescents as possible, these tests should be economic, i. e. as short as possible but at the same time they should fulfil the psychometric quality criteria. We compared the German version of the Eating Attitudes Test (EAT-26D) and the German version of the SCOFF test (which contains only five Yes-no questions) in a sample of 425 twelve year old girls and 382 boys from Thuringia, Germany. Although the EAT-26D reached higher psychometric properties, the SCOFF has been proved as a useful screening tool with a test-retest reliability of rtt = .73 and a maximum accuracy of 82% (area under the ROC curve). In reference to the EAT-26D (20 point cut-off) the sensitivity of the SCOFF was 78%, specificity 75%, positive predictive value 28%, and the negative predictive value, which is more relevant for screenings, was 96%. The construct validity reached r = .52.
This chapter provides the reader with a succinct review surround the issues with uncontrolled pain and provides methods for non-pharmacologic treatment in children. The chapter discusses the sequalae of untreated pain and provides the reader with a detailed explanation of the theory behind distraction techniques. The various distraction techniques are discussed based on age appropriate selection.
To assess the safety of, and subsequent allergy documentation associated with, an antimicrobial stewardship intervention consisting of test-dose challenge procedures prompted by an electronic guideline for hospitalized patients with reported β-lactam allergies.
Retrospective cohort study.
Large healthcare system consisting of 2 academic and 3 community acute-care hospitals between April 2016 and December 2017.
We evaluated β-lactam antibiotic test-dose outcomes, including adverse drug reactions (ADRs), hypersensitivity reactions (HSRs), and electronic health record (EHR) allergy record updates. HSR predictors were examined using a multivariable logistic regression model. Modification of the EHR allergy record after test doses considered relevant allergy entries added, deleted, and/or specified.
We identified 1,046 test-doses: 809 (77%) to cephalosporins, 148 (14%) to penicillins, and 89 (9%) to carbapenems. Overall, 78 patients (7.5%; 95% confidence interval [CI], 5.9%–9.2%) had signs or symptoms of an ADR, and 40 (3.8%; 95% CI, 2.8%–5.2%) had confirmed HSRs. Most HSRs occurred at the second (ie, full-dose) step (68%) and required no treatment beyond drug discontinuation (58%); 3 HSR patients were treated with intramuscular epinephrine. Reported cephalosporin allergy history was associated with an increased odds of HSR (odds ratio [OR], 2.96; 95% CI, 1.34–6.58). Allergies were updated for 474 patients (45%), with records specified (82%), deleted (16%), and added (8%).
This antimicrobial stewardship intervention using β-lactam test-dose procedures was safe. Overall, 3.8% of patients with β-lactam allergy histories had an HSR; cephalosporin allergy histories conferred a 3-fold increased risk. Encouraging EHR documentation might improve this safe, effective, and practical acute-care antibiotic stewardship tool.
The aim of this study was to compare the effect of Hurricane Maria on internalizing and posttraumatic stress disorders (PTSD) among Puerto Ricans who moved to Florida after the storm versus those who stayed on the island.
In March through April 2018 (6 months after Hurricane Maria), an online survey was used to assess the effects of the storm on mental health. A sample of 213 displaced Puerto Ricans living in urban and rural/suburban areas in Florida, as well as urban and rural areas of Puerto Rico, participated in the study.
Rates of PTSD were high in both sites (Florida, 65.7%; Puerto Rico, 43.6%); however, participants in Florida were far more likely than those in Puerto Rico to meet diagnostic criteria for PTSD (OR, 2.94; 95% CI, 1.67-5.26). Among participants in both Florida and Puerto Rico, those living in urban areas were more likely than those in rural/suburban areas to meet criteria for PTSD and generalized anxiety disorder.
Results suggest that post-Hurricane Maria adjustment and adaptation may have been more psychologically taxing for Puerto Ricans who moved to Florida than it was for those who remained on the island, and more difficult for those in urban areas than it was for those in suburban or rural areas. (Disaster Med Public Health Preparedness. 2019;13:24–27)
A great deal of research has focused on acculturation and enculturation, which represent the processes of adapting to a new culture. Despite this growing literature, results have produced inconsistent findings that may be attributable to differences in terms of the instruments used to assess acculturation and enculturation. Utilizing a 3-year longitudinal data set (with 1-year lags between assessments), the present study explored the psychometric properties of the Bicultural Involvement Questionnaire—Short Version (BIQ-S) and the Acculturation Rating Scale for Mexican Americans II (ARSMA-II) and examined the overlap between changes in these measures as they relate to internalizing and externalizing problem behavior. The present sample consisted of 216 immigrant Latino youth (43% boys; mean age 13.6 years at baseline; SD = 1.44 years, range 10 to 17). Exploratory structural equation modeling identified factor structures for the BIQ-S and ARSMA-II that diverged from their hypothesized structure. Growth curve models also indicate divergence between the BIQ-S and ARSMA-II in terms of change in acculturation and enculturation processes. Finally, the present findings emphasized that measures of acculturation and enculturation are not equivalent in terms of their effects on internalizing and externalizing problems.
The Indian residential school (IRS) system in Canada ran for over a century until the last school closed in 1996. Conditions in the IRSs resulted in generations of Indigenous children being exposed to chronic childhood adversity. The current investigation used data from the 2008–2010 First Nations Regional Health Survey to explore whether parental IRS attendance was associated with suicidal thoughts and attempts in childhood, adolescence and in adulthood among a representative sample of First Nations peoples living on-reserve across Canada. Analyses of the adult sample in Study 1 (unweighted n=7716; weighted n=186,830) revealed that having a parent who attended IRS was linked with increased risk for suicidal thoughts and attempts in adolescence and adulthood. Although females were negatively affected by having a parent who attended IRS, the link with suicidal ideation in adulthood was greater for males. Analyses of the youth sample in Study 2 (unweighted n=2883; weighted n=30,190) confirmed that parental IRS attendance was associated with an increased risk for suicidal ideation and attempts. In contrast to the adult sample, parental IRS attendance had a significantly greater relation with suicidal ideation among female youth. A significant interaction also emerged between parental IRS attendance and age in the youth sample, with the influence of parental attendance being particularly strong among youth ages 12–14, compared with those 15–17 years. These results underscore the need for culturally relevant early interventions for the large proportions of Indigenous children and youth intergenerationally affected by IRSs and other collective traumas.
Background: This work proposes a hypothetical model that integrates human factors (e.g. inherent ability and acquired expertise) and task factors (e.g. pre-procedural data, visual and haptic information) to better understand the hand ergonomics adaptation needed for optimal safety and efficiency during simulated brain tumor resections. Methods: Hand ergonomics of neurosurgeons, residents and medical students were assessed during simulated brain tumors resection on the NeuroVR virtual reality neurosurgical simulation platform. Spatial distribution of time expended, force applied, and tumor volume removed, and other metrics were analyzed in each tumor quadrant (Q1 to Q4). Results: Significant differences were observed between the most favorable hand ergonomics condition (Q2) and the unfavorable hand ergonomics condition (Q4). Neurosurgeons applied more total force, more mean force, and removed less tumor per unit of force applied in Q4. However, total volume removed was not significant between the two quadrants indicating hand ergonomics adaptation in order to maximize tumor removal. In comparison, hand ergonomics of medical students remained unchanged in all quadrants, indicating a learning phenomenon. Conclusions: Neurosurgeons are more capable of adapting their hand ergonomics during simulated brain tumor resections. Our proposed hypothetical model integrates our findings with the literature and highlights the importance of experience in the acquisition of adaptive hand ergonomics.
Current standard-of-care for glioblastoma (GBM) includes surgery, radiation and temozolomide. Most tumors recur within a year from diagnosis and median survival for recurrent GBM (rGBM) is 3-9 months. Unmethylated promoter status for O6-methylguanine-DNA-methyltransferase (MGMT) is a validated biomarker for temozolomide-resistance, exhibited by most GBM patients. VAL-083 is a DNA-targeting agent with a mechanism-of-action that is independent of MGMT. VAL-083 overcomes temozolomide-resistance in GBM cell-lines, cancer stem cells, and in vivo models. VAL-083 readily crosses the blood-brain barrier and accumulates in brain-tumor tissue. We recently completed a VAL-083 dose-escalation trial in temozolomide- and bevacizumab-refractory rGBM and determined that 40mg/m2/day given intravenously on days 1,2,3 of a 21-day cycle is generally well-tolerated. This dosing regimen was selected for subsequent GBM trials, including an ongoing single-arm, biomarker-driven Phase 2 trial (N=48) in temolozomide-refractory, bevacizumab-naïve rGBM , MGMT-unmethylated (Clinicaltrials.gov:NCT02717962). The primary objective of this study is to determine if VAL-083 improves OS compared to a historical control of 7.15 months for MGMT-unmethylated rGBM patients treated with lomustine (EORTC26101). In addition, another single-arm, biomarker-driven, Phase 2 study (N=25) of VAL-083 in combination with radiotherapy in newly diagnosed GBM, MGMT-unmethylated is ongoing (Clinicaltrials.gov:NCT03050736). This trial aims to determine a dose for further study of VAL-083 in combination with radiotherapy and explore if VAL-083 improves PFS and OS compared to historical results in newly diagnosed GBM. Enrollment and safety data updates will be provided at the meeting. The results of these studies, if successful, may support VAL-083 as part of a new chemotherapeutic treatment paradigm for GBM.
Policy-makers and practitioners have a need to assess community resilience in disasters. Prior efforts conflated resilience with community functioning, combined resistance and recovery (the components of resilience), and relied on a static model for what is inherently a dynamic process. We sought to develop linked conceptual and computational models of community functioning and resilience after a disaster.
We developed a system dynamics computational model that predicts community functioning after a disaster. The computational model outputted the time course of community functioning before, during, and after a disaster, which was used to calculate resistance, recovery, and resilience for all US counties.
The conceptual model explicitly separated resilience from community functioning and identified all key components for each, which were translated into a system dynamics computational model with connections and feedbacks. The components were represented by publicly available measures at the county level. Baseline community functioning, resistance, recovery, and resilience evidenced a range of values and geographic clustering, consistent with hypotheses based on the disaster literature.
The work is transparent, motivates ongoing refinements, and identifies areas for improved measurements. After validation, such a model can be used to identify effective investments to enhance community resilience. (Disaster Med Public Health Preparedness. 2018;12:127–137)
Recent issues of Antiquity have seen much discussion on the topic of Carthaginian infant sacrifice: was it a Graeco-Roman fiction or did it really happen? There are strongly held opinions on both sides of the argument, with much resting on the age profile of the children interred at the cemetery known as the Carthage Tophet. Here, the authors respond to claims by Smith et al. (2011, 2013) that their ageing of the infants and children was incorrect, and so also by extension was their interpretation that not all interments at the Tophet were the result of sacrifice.
Glioblastoma (GBM) is the most common brain cancer. Most GBM tumors have unmethylated promoter status for O6-methylguanine-DNA-methyltransferase (MGMT); a validated biomarker for MGMT protein-expression and ensuing temozolomide-resistance. Second-line treatment with bevacizumab has not improved overall survival (OS). Dianhydrogalactitol (VAL-083) is a bi-functional alkylating agent targeting N7-Guanine, thus MGMT-independently inducing interstrand cross-links, DNA double-strand breaks and cell-death in GBM cell-lines and cancer stem cells. VAL-083 is currently in Phase I/II clinical trial for recurrent GBM, post-TMZ and post-bevacizumab. In this Phase II clinical trial, the main goal is to assess the 9-month OS in MGMT-unmethylated, recurrent, bevacizumab-naive GBM. RATIONALE: The vast majority of GBM patients experience recurrent/progressive disease within a year from initial diagnosis and median survival after recurrence is 3-9 months. Chemotherapy regimens for these patients are lacking and there is a significant unmet medical need. Given VAL-083’s novel alkylating mechanism, promising clinical benefit, and favorable safety profile, a trial studying VAL-083 in MGMT-unmethylated recurrent GBM is warranted. METHOD: Randomized, non-comparative biomarker-driven Phase II clinical trial in MGMT-unmethylated GBM patients at first recurrence/progression, prior to bevacizumab. 48 patients will be randomized to receive VAL-083 or “standard-of-care” salvage drug lomustine. 32 patients will receive VAL-083 40mg/m2/day on days 1,2,3 of a 21-day cycle. 16 patients will receive lomustine 90 mg/m2/day on day 1 of a 42-day cycle. Patients will be followed until death or for at least 9 months from enrollment, whichever occurs earlier. Survival will be compared to the BELOB trial for recurrent MGMT-unmethylated GBM patients treated with lomustine.