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Foliar-applied postemergence applications of glufosinate are often applied to glufosinate-resistant crops to provide nonselective weed control without significant crop injury. Rainfall, air temperature, solar radiation, and relative humidity near the time of application have been reported to affect glufosinate efficacy. However, previous research may have not captured the full range of weather variability to which glufosinate may be exposed before or following application. Additionally, climate models suggest more extreme weather will become the norm, further expanding the weather range to which glufosinate can be exposed. The objective of this research was to quantify the probability of successful weed control (efficacy ≥85%) with glufosinate applied to some key weed species across a broad range of weather conditions. A database of >10,000 North American herbicide evaluation trials was used in this study. The database was filtered to include treatments with a single postemergence application of glufosinate applied to waterhemp [Amaranthus tuberculatus (Moq.) Sauer], morningglory species (Ipomoea spp.), and/or giant foxtail (Setaria faberi Herrm.) <15 cm in height. These species were chosen because they are well represented in the database and listed as common and troublesome weed species in both corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] (Van Wychen 2020, 2022). Individual random forest models were created. Low rainfall (≤20 mm) over the 5 d before glufosinate application was detrimental to the probability of successful control of A. tuberculatus and S. faberi. Lower relative humidity (≤70%) and solar radiation (≤23 MJ m−1 d−1) on the day of application reduced the probability of successful weed control in most cases. Additionally, the probability of successful control decreased for all species when average air temperature over the first 5 d after application was ≤25 C. As climate continues to change and become more variable, the risk of unacceptable control of several common species with glufosinate is likely to increase.
The association between cannabis and psychosis is established, but the role of underlying genetics is unclear. We used data from the EU-GEI case-control study and UK Biobank to examine the independent and combined effect of heavy cannabis use and schizophrenia polygenic risk score (PRS) on risk for psychosis.
Methods
Genome-wide association study summary statistics from the Psychiatric Genomics Consortium and the Genomic Psychiatry Cohort were used to calculate schizophrenia and cannabis use disorder (CUD) PRS for 1098 participants from the EU-GEI study and 143600 from the UK Biobank. Both datasets had information on cannabis use.
Results
In both samples, schizophrenia PRS and cannabis use independently increased risk of psychosis. Schizophrenia PRS was not associated with patterns of cannabis use in the EU-GEI cases or controls or UK Biobank cases. It was associated with lifetime and daily cannabis use among UK Biobank participants without psychosis, but the effect was substantially reduced when CUD PRS was included in the model. In the EU-GEI sample, regular users of high-potency cannabis had the highest odds of being a case independently of schizophrenia PRS (OR daily use high-potency cannabis adjusted for PRS = 5.09, 95% CI 3.08–8.43, p = 3.21 × 10−10). We found no evidence of interaction between schizophrenia PRS and patterns of cannabis use.
Conclusions
Regular use of high-potency cannabis remains a strong predictor of psychotic disorder independently of schizophrenia PRS, which does not seem to be associated with heavy cannabis use. These are important findings at a time of increasing use and potency of cannabis worldwide.
Foliar-applied postemergence herbicides are a critical component of corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] weed management programs in North America. Rainfall and air temperature around the time of application may affect the efficacy of herbicides applied postemergence in corn or soybean production fields. However, previous research utilized a limited number of site-years and may not capture the range of rainfall and air temperatures that these herbicides are exposed to throughout North America. The objective of this research was to model the probability of achieving successful weed control (≥85%) with commonly applied postemergence herbicides across a broad range of environments. A large database of more than 10,000 individual herbicide evaluation field trials conducted throughout North America was used in this study. The database was filtered to include only trials with a single postemergence application of fomesafen, glyphosate, mesotrione, or fomesafen + glyphosate. Waterhemp [Amaranthus tuberculatus (Moq.) Sauer], morningglory species (Ipomoea spp.), and giant foxtail (Setaria faberi Herrm.) were the weeds of focus. Separate random forest models were created for each weed species by herbicide combination. The probability of successful weed control deteriorated when the average air temperature within the first 10 d after application was <19 or >25 C for most of the herbicide by weed species models. Additionally, drier conditions before postemergence herbicide application reduced the probability of successful control for several of the herbicide by weed species models. As air temperatures increase and rainfall becomes more variable, weed control with many of the commonly used postemergence herbicides is likely to become less reliable.
Declining labor force participation of older men throughout the 20th century and recent increases in participation have generated substantial interest in understanding the effect of public pensions on retirement. The National Bureau of Economic Research's International Social Security (ISS) Project, a long-term collaboration among researchers in a dozen developed countries, has explored this and related questions. The project employs a harmonized approach to conduct within-country analyses that are combined for meaningful cross-country comparisons. The key lesson is that the choices of policy makers affect the incentive to work at older ages and these incentives have important effects on retirement behavior.
Braidwood Management, Inc. v. Becerra challenges the Affordable Care Act free preventive coverage guarantee. Community health centers serve over 30 million residents of medically underserved urban and rural communities. Their limited federal grant funding makes them reliant on insurance revenue for their operations, Medicaid and subsidized marketplace coverage in particular, both of which are implicated by the case. To understand these implications, we developed an analytic model that crosswalks the preventive services potentially affected by Braidwood and the preventive care that all health centers must furnish. Of the 193 preventive services now covered under the guarantee, only forty-eight would survive were the Braidwood plaintiffs to prevail. In underserved communities, health centers are a principal source of the nearly 150 affected services, as evidenced by the care they are required to furnish under federal law, the quality metrics they are expected to meet, and the health diagnoses and treatments identified in federal performance reporting requirements. Thus, the impact on access, quality, patient health, and health center finances and care capability will likely be substantial.
Most evidence on suicidal thoughts, plans and attempts comes from Western countries; prevalence rates may differ in other parts of the world.
Aims
This study determined the prevalence of suicidal thoughts, plans and attempts in high school students in three different regional settings in Kenya.
Method
This was a cross-sectional study of 2652 high school students. We asked structured questions to determine the prevalence of various types of suicidality, the methods planned or effected, and participants’ gender, age and form (grade level). We provided descriptive statistics, testing significant differences by chi-squared and Fisher's exact tests, and used logistic regression to identify relationships among different variables and their associations with suicidality.
Results
The prevalence rates of suicidal thoughts, plans and attempts were 26.8, 14.9 and 15.7%, respectively. These rates are higher than those reported for Western countries. Some 6.7% of suicide attempts were not associated with plans. The most common method used in suicide attempts was drinking chemicals/poison (18.8%). Rates of suicidal thoughts and plans were higher for older students and students in urban rather than rural locations, and attempts were associated with female gender and higher grade level – especially the final year of high school, when exam performance affects future education and career prospects.
Conclusion
Suicidal thoughts, plans and attempts are prevalent in Kenyan high school students. There is a need for future studies to determine the different starting points to suicidal attempts, particularly for the significant number whose attempts are not preceded by thoughts and plans.
With a public health crisis gripping the UK, this book examines the organisational and political barriers to an effective public health system and determines that a new social contract is needed, in which health policy is truly public.
The UK faces a health crisis. In 2018–20 growth in life expectancy stalled for women and declined for men, taking men back to the level in 2012–14 (ONS, 2021). Although the immediate cause was the outbreak of COVID-19 in 2020, a slowing-down in improvements in life expectancy had been happening for a decade, particularly affecting the most deprived 10 per cent of the population, and falling or stagnating for some groups (Marmot, 2022). In other comparable economies, life expectancy has increased at a faster rate (OECD, 2023), so the latest figures are the culmination of a longer term trend. But COVID-19 also led to a surge in the number of those of the working-age population being unfit for work through extended sickness. Before 2020, less than 5 per cent of the relevant population were unfit for work in this way; by 2022, it was more than 6 per cent (Neville and Borrett, 2023). COVID-19 hit the UK population hard because there had been a failure of public health planning over many years. The result was the growth in a number of health risks that bring illness in their wake and impose severe strains on the National Health Service (NHS). The omens in respect of these health risks look poor.
Consider obesity. As Figure 1.1 shows, obesity rates are high in the UK when set against comparable western European countries. While obesity has increased in all the high-income countries, rates in the UK more than tripled between 1975 and 2016, whereas France and Germany showed much lower rates of growth, as did other European countries like Italy. To be sure, the UK does not equal the US or Australia in its obesity, but it is closer to them than to its European neighbours. Obesity is an important public health measure because being obese leads to a predictor of poor health, causing strain on the skeleton and increasing the risk of fatal heart attacks or stroke. It also leads to an increased risk of type 2 diabetes, a disease that is responsible for some 10 per cent of NHS expenditure.
The background to this book was a research study that took place in 2021 and 2022. It sought to understand the circumstances surrounding the abolition of the main institution responsible for public health in England – Public Health England (PHE) – and its replacement by the UK Health Security Agency and the Office for Health Improvement and Disparities. As well as collecting data from published reports, national and parliamentary committee meetings and interviews, we also collected information on the structure of public health governmental organisations in the UK. The main study findings can be found here: https://arc-sl.nihr.ac.uk/sites/default/files/uploads/files/public-health-report-sept-2022-final.pdf (Littlejohns et al, 2022c).
The relevant issues that emerged as we described how PHE was closed can be found in a paper we published in Health Economics Policy and Law (Weale et al, 2023).
While the reasons were complex, they could be summarised by two competing interpretations: an ‘official’ explanation, which highlights the failure of PHE to scale up its testing capacity in the early weeks of the COVID-19 pandemic as the fundamental reason for closing it down; and a ‘sceptical’ interpretation, which ascribes the decision to blame-avoidance behaviour on the part of leading government figures. We reviewed crucial claims in these two competing explanations, exploring the arguments for and against each proposition. We concluded that neither was adequate and that the inability to address the problem of testing (which triggered the decision to close PHE) lies deeper, in the absence of the norms of responsible government in UK politics and the state. However, our findings did provide some guidance to the two new organisations established to replace PHE to maximise their impact on public health.
We then continued our thinking of what was required and presented a flavour of it in a Lancet Public Health Viewpoint article by Hunter, Littlejohns and Weale on ‘Reforming the public health system in England’ (Hunter et al, 2022).
We came to the conclusion that a completely new way of thinking about public health was required, and that would only be achieved by establishing a new social contract with the British people.
There is now general agreement that the UK is facing a public health crisis. Improvements in life expectancy have stalled, health inequalities are continuing to widen, obesity and alcohol misuse are placing an increasing strain on health services, and urban air pollution is now widely recognised as a serious health hazard. However, consensus on possible solutions is absent. COVID-19 revealed the weaknesses of the UK’s public health system – once thought to be among the best in the world. While we are still waiting for the official Covid-19 Inquiry to report its findings, an increasing number of studies are demonstrating where the problems lie – not only in infectious disease control but more generally in public health. Our own research study took place in 2021 and 2022, and sought to understand the circumstances surrounding the abolition of the main institution responsible for public health in England – Public Health England – and its replacement by the UK Health Security Agency and the Office for Health Improvement and Disparities. The publications that emerged from that original study are detailed in an appendix.
Our findings convinced us that what is urgently needed is much broader than simply targeted interventions. A fundamental public policy debate is necessary to stimulate interest in the vital importance of public health and a new approach initiated. We have come to the conclusion that a completely new way of thinking about public health is required, and that would only be achieved by establishing by a new social contract for the UK population. We are not alone in thinking that fundamental change is required. The Institute for Public Policy Research (IPPR, 2023) recently published its first interim report on health in the UK, advocating a new Health and Prosperity Act supported by a Committee on Health and Prosperity – modelled on the Climate Change Committee and designed to independently advise on the above mission (and hold all governments accountable to it).
Our book does not try to revisit all the theories and initiatives to improve public health but explores some of the fundamental barriers and why interventions (even those based on good evidence) are not adequately implemented. We address several key political and governance issues around the social contract idea. We build on the thinking outlined in the history of public health by David Hunter et al, The Public Health System in England (Policy Press, 2010).
As we saw in the previous two chapters, the UK now has a new public health settlement. As far as England is concerned, in place of Public Health England (PHE), there are now two bodies, the UK Health Security Agency (UKHSA), with primary responsibility for health protection, and the Office for Health Improvement and Disparities (OHID), with primary responsibility for health promotion. (UKHSA also has responsibility for non-devolved health matters for the whole of the UK.) In addition, the administrative structure of the NHS has been altered with the establishment of integrated care systems (ICSs) intended to bring together local authorities, the NHS and other agencies with the intention of taking a population-based perspective. The one part of the original 2013 Lansley reforms that survived these changes concerns the public health responsibilities of local authorities.
The English reforms have been high-profile changes. Developments in Scotland, Wales and Northern Ireland, while significant, have largely involved a concentration of public health responsibilities over time as part of planned changes to administrative arrangements. In each case, however, the direction of change is the opposite of what has occurred in England. Instead of a separation of health protection and health promotion, the devolved governments have created integrated bodies. These bodies still have to liaise with local government, but they do so from a position in which public health can be seen as a set of overall responsibilities.
This chapter focuses on the policy and process issues to which these new structures give rise. The Hancock reforms, like many machinery of government changes, underline the point that, in some circumstances, organisational arrangements become the prime object of policy. Reorganisation provides a way of deflecting blame and also a way of seeming to make a new start quickly and visibly. Moreover, machinery of government changes are attractive to high-level political representatives, since they signal interest in an area of policy without the need to go into detail about any one aspect of policy. Thus, the political attraction of reorganisation is that it makes the politician play the role of God in eighteenth-century Christian theology, whose responsibility was to create the system that would then look after itself, according to its own laws. However, successful policy must go beyond the establishment of new organisations.
In the previous chapter we saw how Public Health England (PHE) was the product of the Lansley broader reforms of the NHS, reforms that also included the return of public health functions to local government. A notable feature of the transformation of the UK since 1998 has been the extension and devolution of powers from Westminster and Whitehall to Scotland, Wales and Northern Ireland. Devolution means that in areas of policy that are not reserved to the UK government, which in health policy are very few, the governments of the home nations have the freedom to determine their own policies, priorities and structures. This has been notably true in the provision of health care services, where the Welsh, Scottish and Northern Ireland governments have opted for greater stability in place of successive structural reforms, and have not made competition and performance management a central guiding principle as the UK government has done to an increasing degree since the Thatcher reforms. However, the distinctiveness has also shown up in public health policies and structures.
Looking at public health in the devolved governments is important for a number of reasons, quite apart from the simple need to avoid Anglo-centrism. In the first place, the organisation of public health in the devolved governments provides interesting points of similarity and difference to those in England. If the replacement of PHE took place without any forethought, the same is not true in the other home nations where, in keeping with health care services, there has been great stability of organisation, alongside policy developments. So patterns of structural organisation provide interesting evidence of the various ways in which public health functions can be organised. As we shall see in this chapter, there is no one uniform set of functions that are the responsibility of the public health bodies. Functions that are the responsibility of a public health agency in one of the home nations may be the responsibility of, say, the environment agency of another home nation.
Variation in the home nations in the organisation of public health also potentially poses another challenge to effective public health. If public health requires intersectoral collaboration across government, the conduct of policy in the UK requires collaboration across the governments of the home nations.