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Aortic coarctation can occur isolated or associated with ventricular septal defect. This study evaluated aortic stiffness in normotensive patients surgically treated for aortic coarctation and ventricular septal defect and in those who underwent simple aortic coarctation repair. Both groups were compared with healthy controls. Again, the two pathological groups were compared with each other regarding aortic stiffness and left ventricular diastolic function. A possible relationship between aortic stiffness and left ventricular diastolic function was investigated.
Methods:
Twenty-two isolated aortic coarctation patients and 17 aortic coarctation and ventricular septal defect patients were enrolled. Aortic root distensibility and aortic stiffness index were calculated from echocardiography and blood pressure. E wave to A wave (E/A) ratio was measured from mitral valve inflow profile.
Results:
Aortic root distensibility and aortic stiffness index in simple aortic coarctation vs healthy controls: both p < 0.0001. Aortic root distensibility and aortic stiffness index in aortic coarctation/ventricular septal defect vs healthy controls: both p < 0.0001. Aortic root distensibility and aortic stiffness index were similar in the two pathological groups (both p = ns). No statistically significant difference was detected in relation to left ventricular diastolic function (p = ns). No correlation was detected between aortic stiffness and diastolic function in simple aortic coarctation and aortic coarctation/ventricular septal defect groups (both p = ns).
Conclusions:
In both normotensive isolated aortic coarctation and aortic coarctation/ventricular septal defects subgroups, aortic stiffness is increased in a similar way in comparison with controls. Diastolic function was normal and similar in both groups. Aortic stiffness was not related to left ventricular diastolic function in this specific setting.
Concerns about penicillin-cephalosporin cross-reactivity have historically led to conservative prescribing and avoidance of cephalosporins in patients with penicillin allergy labels, potentially causing suboptimal outcomes. Recent evidence suggests a lower risk of cross-reactivity, prompting a reassessment of alert systems.
Objective:
To assess the impact of limited penicillin cross-reactivity alerts on outpatient cephalosporin use and the incidence of adverse reactions in a healthcare setting.
Methods:
This retrospective cohort study compared cephalosporin prescribing and adverse reactions in patients labeled as penicillin-allergic before and after limiting penicillin cross-reactivity alerts in the electronic medical record at a large academic medical center.
Results:
Among 17,174 patients (8,131 pre- and 9,043 post-implementation), there was a statistically significant increase in outpatient cephalosporin prescribing by 8% (P < .001). The use of alternative antibiotic classes decreased. There was no statistically significant increase in adverse events pre- and post-implementation (0.036%–0.058%, P = .547), and no severe events were attributable to cross-reactivity. The alert modification reduced alerts by 92% (P < .001).
Conclusion:
The reduction of penicillin-cephalosporin cross-reactivity alerts was associated with increased cephalosporin use, without a significant increase in adverse reactions. This demonstrates that the practice is safe and decreases alert burden.
Our national scientific enterprise has a crisis of reproducibility. While this phenomenon has many contributors, one is the proliferation of data manipulation. Data manipulation may range from seemingly innocuous to brazen to the point of verging on criminal. This latter category has recently received more attention, stimulating a debate about the handling of such unpleasant matters. We co-authors have instigated and interacted with numerous research integrity investigations and believe the current model of handling potential violations of research integrity standards is deeply flawed. Institution-led investigations are fundamentally conflicted because of the potential for institutional reputational damage and financial harm from a finding of research misconduct. Concerns are often handled with secrecy, lethargy, and limited technical analysis. Integrity lapses are frequently handled with a lack of openness, accountability and proportional consequences, which have weakened public trust in the scientific enterprise.
We propose that research integrity violations of substantial scale should be independently investigated by appropriately resourced specialists. Such investigations should be completed within a time frame that facilitates meaningful corrective action when required or exoneration of the accused party when appropriate; completion of an investigation should rarely extend beyond one year and the results of the investigation should be made public.
This paper presents a set of theoretical models that links a two-phase sequence of cooperative political integration and conflict to explore the reciprocal relationship between war and state formation. It compares equilibria rates of state formation and conflict using a Monte Carlo that generates comparative statics by altering the systemic distribution of ideology, population, tax rates, and war costs across polities. This approach supports three core findings. First, war-induced political integration is at least 2.5 times as likely to occur as integration to realize economic gains. Second, we identify mechanisms linking endogenous organizations to the likelihood of conflict in the system. For example, a greater domestic willingness to support public goods production facilitates the creation of buffer states that reduce the likelihood of a unique class of trilateral wars. These results suggest that the development of the modern administrative state has helped to foster peace. Third, we explore how modelling assumptions setting the number of actors in a strategic context can shape conclusions about war and state formation. We find that dyadic modelling restrictions tend to underestimate the likelihood of cooperative political integration and overestimate the likelihood of war relative to a triadic modelling context.
Designing and conducting clinical trials is challenging for some institutions and researchers due to associated time and personnel requirements. We conducted recruitment, screening, informed consent, study product distribution, and data collection remotely. Our objective is to describe how to conduct a randomized clinical trial using remote and automated methods.
Methods:
A randomized clinical trial in healthcare workers is used as a model. A random group of workers were invited to participate in the study through email. Following an automated process, interested individuals scheduled consent/screening interviews. Enrollees received study product by mail and surveys via email. Adherence to study product and safety were monitored with survey data review and via real-time safety alerts to study staff.
Results:
A staff of 10 remotely screened 406 subjects and enrolled 299 over a 3-month period. Adherence to study product was 87%, and survey data completeness was 98.5% over 9 months. Participants and study staff scored the System Usability Scale 93.8% and 90%, respectively. The automated and remote methods allowed the study maintenance period to be managed by a small study team of two members, while safety monitoring was conducted by three to four team members. Conception of the trial to study completion was 21 months.
Conclusions:
The remote and automated methods produced efficient subject recruitment with excellent study product adherence and data completeness. These methods can improve efficiency without sacrificing safety or quality. We share our XML file for researchers to use as a template for learning purposes or designing their own clinical trials.
Protoporphyrinogen oxidase (PPO)-inhibiting herbicides remain an important and useful chemistry 60 yr after their first introduction. In this review, based on topics introduced at the Weed Science Society of America 2021 symposium titled “A History, Overview, and Plan of Action on PPO Inhibiting Herbicides,” we discuss the current state of PPO-inhibiting herbicides. Renewed interest in the PPO-inhibiting herbicides in recent years, due to increased use and increased cases of resistance, has led to refinements in knowledge regarding the mechanism of action of PPO inhibitors. Herein we discuss the importance of the two isoforms of PPO in plants, compile a current knowledge of target-site resistance mechanisms, examine non–target site resistance cases, and review crop selectivity mechanisms. Consistent and reproducible greenhouse screening and target-site mutation assays are necessary to effectively study and compare PPO-inhibitor resistance cases. To this end, we cover best practices in screening to accurately identify resistance ratios and properly interpret common screens for point mutations. The future of effective and sustainable PPO-inhibitor use relies on development of new chemistries that maintain activity on resistant biotypes and the promotion of responsible stewardship of PPO inhibitors both new and old. We present the biorational design of the new PPO inhibitor trifludimoxazin to highlight the future of PPO-inhibitor development and discuss the elements of sustainable weed control programs using PPO inhibitors, as well as how responsible stewardship can be incentivized. The sustained use of PPO inhibitors in future agriculture relies on the effective and timely communication from mode of action and resistance research to agronomists, Extension workers, and farmers.
Accurate knowledge of the ice thickness distribution and glacier bed topography is essential for predicting dynamic glacier changes and the future developments of downstream hydrology, which are impacting the energy sector, tourism industry and natural hazard management. Using AIR-ETH, a new helicopter-borne ground-penetrating radar (GPR) platform, we measured the ice thickness of all large and most medium-sized glaciers in the Swiss Alps during the years 2016–20. Most of these had either never or only partially been surveyed before. With this new dataset, 251 glaciers – making up 81% of the glacierized area – are now covered by GPR surveys. For obtaining a comprehensive estimate of the overall glacier ice volume, ice thickness distribution and glacier bed topography, we combined this large amount of data with two independent modeling algorithms. This resulted in new maps of the glacier bed topography with unprecedented accuracy. The total glacier volume in the Swiss Alps was determined to be 58.7 ± 2.5 km3 in the year 2016. By projecting these results based on mass-balance data, we estimated a total ice volume of 52.9 ± 2.7 km3 for the year 2020. Data and modeling results are accessible in the form of the SwissGlacierThickness-R2020 data package.
Does social media educate voters, or mislead them? This study measures changes in political knowledge among a panel of voters surveyed during the 2015 UK general election campaign while monitoring the political information to which they were exposed on the Twitter social media platform. The study's panel design permits identification of the effect of information exposure on changes in political knowledge. Twitter use led to higher levels of knowledge about politics and public affairs, as information from news media improved knowledge of politically relevant facts, and messages sent by political parties increased knowledge of party platforms. But in a troubling demonstration of campaigns' ability to manipulate knowledge, messages from the parties also shifted voters' assessments of the economy and immigration in directions favorable to the parties' platforms, leaving some voters with beliefs further from the truth at the end of the campaign than they were at its beginning.
Background: As of July 1, 2019, ~18% of all cases in the Ebola virus disease (EVD) outbreak in the Democratic Republic of Congo (DRC) were healthcare-associated (ie, nosocomial) infections (HAIs) and healthcare worker (HCW) infections. Although progress has been achieved, gaps remained in infection prevention and control (IPC), specifically, a need to reinforce standardized, evidence-based IPC practices to effectively address HAIs. The Ministry of Health (MOH), in collaboration with partners, developed an IPC tool kit consisting of >70 documents (ie, terms of reference, standard operating procedures, training modules, etc) to improve HCW IPC knowledge and practices at healthcare facilities among staff. The tool kit incorporated international IPC standards, DRC-specific experiences, and best practices. Thus, it serves as a technical and operational package, covering general guidance (standard precautions) and EVD specific issues. Methods: A decentralized rollout approach was used to disseminate the tool kit content at the various health-system levels over several months. Initially, national-level training of trainers was held, followed by subnational-level training of IPC supervisors and key IPC implementers, and lastly, training of healthcare facility (HCF) IPC focal persons. The 5-day training adhered to the MOH standard of 60% theory and 40% practice. Participants completed evaluations before and after training; changes in knowledge between the pre- and posttraining tests were analyzed and the results of the statistical tests were reported (P < .05 was considered statistically significant). Results: In total, 294 IPC supervisors were trained across 7 subnational commissions. Data were analyzed for 138 participants. Participants were 60.9% IPC supervisors, 8% WASH supervisors, and 31% others. MOH representation was 52.9% The average results before the test were 66% (19.8 of 30), the average posttest results were 72% (21.6 of 30)—a significant improvement. The worst-performing pretest IPC domain was IPC approach, and facility closure was the worst performing for posttest. As of November 11, 15.7% of all cases were HAIs. Conclusions: The IPC training program initiated during an outbreak can increase knowledge and potentially improve practices and confidence. An association with the downward HAI trend is yet to be validated. The MOH anticipates that this tool kit will be the go-to resource for future Ebola outbreaks and that it will be incorporated into the preservice medical curriculum to ensure a resilient heath system.
Background: With >3,000 cases and 2,000 deaths, the current outbreak of Ebola virus disease (EVD) in the Democratic Republic of the Congo (DRC) is the second-largest reported EVD outbreak in history. Healthcare-associated transmission of EVD has been a persistent amplifier of transmission due, in part, to fragility of the healthcare system, lack of basic infection prevention and control (IPC) infrastructure, and large number of healthcare facilities (HCFs). A central component of the strategy to rapidly strengthen IPC in HCFs is the provision of IPC supervisors to oversee standardized risk assessments and improvements and provide mentorship to HCF staff. To support these activities, we designed skills based training for IPC supervisors. Methods: Staff recruited by the Ministry of Health (MoH) to strengthen IPC are part of an outbreak-specific cadre known as IPC supervisors. IPC supervisors, who originally lacked technical knowledge and mentoring experience, were trained to provide technical support and mentorship to staff at HCFs, with the objective of improving IPC-related processes and behaviors. A competency-based training course was designed by conducting informal assessments of IPC supervisors during daily tasks to identify areas for performance improvement. We developed competencies based on activities designated for IPC supervisors according to MoH guidelines. We planned an iterative training rollout to allow for continuous, real-time modifications based on lessons learned throughout the implementation phase. Results: Although IPC supervisors displayed technical knowledge of IPC recommendations, we observed large gaps in implementation. IPC supervisors frequently failed to recognize behaviors that are high-risk for infection transmission. In addition, IPC supervisors lacked the ability to develop prioritized action plans and to implement interventions aimed at rapidly improving IPC practices. The course, designed as an interactive, skills-based training, is rooted in instructional design principles and addresses 4 key competencies: risk recognition and prioritization, IPC assessment completion, action plan development, and effective leadership and communication. The course will be pilot tested in the DRC to an audience of 25 IPC supervisors. Conclusions: In an outbreak setting, strong mentorship and problem-solving skills are needed to support effective implementation of IPC quality improvement. Trainings that are informed by field experiences and teach problem-solving, coaching, and communication skills are critical and can be developed rapidly. The strategy employed by the Ministry of Health to rapidly achieve IPC capacitation at HCFs might be adapted for use in future outbreaks.
We present a sediment-mixing process model of till genesis based on data from surface tills of the Saginaw lobe terrain in lower Michigan. Our research uses a spatial approach to understanding glacial landsystems and till genesis. We sampled calcareous till at 336 upland sites and at 17 sites in lacustrine sediment of the Saginaw Lake plain. The loamy tills have bimodal grain-size curves, with a fine-texture mode near the silt–clay boundary and a sand mode. Spatial grouping analysis suggests that tills can be divided into six groups, each with different textures and clay mineral compositions that vary systematically down-ice. The similarity among groups with respect to the silt–clay mode and clay mineralogy argues for a common origin for the fines—illite-rich lacustrine sediment of the Saginaw Lake plain. Fine-textured sediments were probably entrained, transported, and deposited down-ice as till, which also becomes sandier and enriched in kaolinite, reflecting increasing mixing with shallow sandstone bedrock with distance from the lacustrine clay source. Clayey tills on the flanks of the Saginaw terrain may reflect proglacial ponding against nearby uplands. A process model of progressive down-ice mixing of preexisting fine lake sediments with crushed/abraded sandstone bedrock helps to better explain till textures compared with a purely crushing/abrasion process model.
Stratigraphic records extending to Marine Oxygen Isotope Stage (MIS) 3 (57,000–29,000 cal yr BP) or older in Beringia are extremely rare. Three stratigraphic sections in interior western Alaska show near continuous sedimentological and environmental progressions extending from at least MIS 3, if not older, through MIS 1 (14,000 cal yr BP–present). The Kolmakof, Sue Creek, and VABM (vertical angle bench mark) Kuskokwim sections along the central Kuskokwim River, once a highland landscape at the fringe of central and eastern Beringia, contain aeolian deposition and soil sequences dating beyond 50,000 14C yr BP. Thick peaty soil, shallow lacustrine, and tephra deposits represent the MIS 3 interstade (or older). Sand sheet and loess deposits, wedge cast development, and very thin soil development mark the later MIS 3 period and the transition into the MIS 2 stade (29,000–14,000 cal yr BP). Loess accumulation with thicker soil development occurred between ~16,000–13,500 cal yr BP at the MIS 2 and MIS 1 transition. After ~13,500 cal yr BP, loess accumulation waned and peat development increased throughout MIS 1. These stratigraphic sequences represent transitions between a warm and moist period during MIS 3, to a cooler and more arid period during MIS 2, then a return to warmer and moister climates in MIS 1.
The South China Sea (SCS) is a biodiversity hotspot, however, most biodiversity surveys in the region are confined to shallow water reefs. Here, we studied the benthic habitat and fish assemblages in the upper mesophotic coral ecosystems (MCEs; 30–40 m) and SWRs (8–22 m) at three geographic locations (Luzon Strait; Palawan; and the Kalayaan Group of Islands) in the eastern SCS (also called the West Philippine Sea) using diver-based survey methods. Mean coral genera and fish species richness ranged from 17–25 (per 25 m2) and 11–17 (per 250 m2) in MCEs, respectively; although none of these were novel genera/species. Coral and fish assemblages were structured more strongly by location than by depth. Location differences were associated with the variability in benthic composition, wherein locations with higher hard coral cover had higher coral genera richness and abundance. Locations with higher algae and sand cover had higher diversity and density of fish herbivores and benthic invertivores. Fishing efforts may also have contributed to among-location differences as the highly exploited location had the lowest fish biomass. The low variation between depths may be attributed to the similar benthic composition at each location, the interconnectivity between depths due to hydrological conditions, fish motility, and the common fishing gears used in the Philippines that can likely extend beyond SWRs. Results imply that local-scale factors and anthropogenic disturbances probably dampen across-depth structuring in coral genera and fish species assemblages.
We propose the concept of the “Fish Revolution” to demarcate the dramatic increase in North Atlantic fisheries after AD 1500, which led to a 15-fold increase of cod (Gadus morhua) catch volumes and likely a tripling of fish protein to the European market. We consider three key questions: (1) What were the environmental parameters of the Fish Revolution? (2) What were the globalising effects of the Fish Revolution? (3) What were the consequences of the Fish Revolution for fishing communities? While these questions would have been considered unknowable a decade or two ago, methodological developments in marine environmental history and historical ecology have moved information about both supply and demand into the realm of the discernible. Although much research remains to be done, we conclude that this was a major event in the history of resource extraction from the sea, mediated by forces of climate change and globalisation, and is likely to provide a fruitful agenda for future multidisciplinary research.
A new deep level transient spectroscopy (DLTS) technique is described, called half-width at variable intensity analysis. This method utilizes the width and normalized intensity of a DLTS signal to determine the activation energy and capture cross section of the trap that generated the signal via a variable, kO. This constant relates the carrier emission rates giving rise to the differential capacitance signal associated with a given trap at two different temperatures: the temperature at which the maximum differential capacitance is detected, and an arbitrary temperature at which some nonzero differential capacitance signal is detected. The extracted activation energy of the detected trap center is used along with the position of the peak maximum to extract the capture cross section of the trap center.