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Analysts and policymakers often decry the failure of institutions to accomplish their stated purpose. Bringing together leading scholars of Latin American politics, this volume helps us understand why. The volume offers a conceptual and theoretical framework for studying weak institutions. It introduces different dimensions of institutional weakness and explores the origins and consequences of that weakness. Drawing on recent research on constitutional and electoral reform, executive–legislative relations, property rights, environmental and labor regulation, indigenous rights, squatters and street vendors, and anti-domestic violence laws in Latin America, the volume's chapters show us that politicians often design institutions that they cannot or do not want to enforce or comply with. Challenging existing theories of institutional design, the volume helps us understand the logic that drives the creation of weak institutions, as well as the conditions under which they may be transformed into institutions that matter.
Iraq and Afghanistan Veterans with posttraumatic stress disorder (PTSD) and traumatic brain injury (TBI) history have high rates of performance validity test (PVT) failure. The study aimed to determine whether those with scores in the invalid versus valid range on PVTs show similar benefit from psychotherapy and if psychotherapy improves PVT performance.
Veterans (N = 100) with PTSD, mild-to-moderate TBI history, and cognitive complaints underwent neuropsychological testing at baseline, post-treatment, and 3-month post-treatment. Veterans were randomly assigned to cognitive processing therapy (CPT) or a novel hybrid intervention integrating CPT with TBI psychoeducation and cognitive rehabilitation strategies from Cognitive Symptom Management and Rehabilitation Therapy (CogSMART). Performance below standard cutoffs on any PVT trial across three different PVT measures was considered invalid (PVT-Fail), whereas performance above cutoffs on all measures was considered valid (PVT-Pass).
Although both PVT groups exhibited clinically significant improvement in PTSD symptoms, the PVT-Pass group demonstrated greater symptom reduction than the PVT-Fail group. Measures of post-concussive and depressive symptoms improved to a similar degree across groups. Treatment condition did not moderate these results. Rate of valid test performance increased from baseline to follow-up across conditions, with a stronger effect in the SMART-CPT compared to CPT condition.
Both PVT groups experienced improved psychological symptoms following treatment. Veterans who failed PVTs at baseline demonstrated better test engagement following treatment, resulting in higher rates of valid PVTs at follow-up. Veterans with invalid PVTs should be enrolled in trauma-focused treatment and may benefit from neuropsychological assessment after, rather than before, treatment.
Smallflower umbrella sedge is a prolific C3 weed commonly found in rice fields in 47 countries. The increasing infestation of herbicide-resistant smallflower umbrella sedge populations threatens rice production. Our objectives for this study were to characterize thermal requirements for germination of smallflower umbrella sedge seeds from rice fields in California and to parameterize a population thermal-time model for smallflower umbrella sedge germination. Because the use of modeling techniques is hampered by the lack of thermal-time model parameters for smallflower umbrella sedge seed germination, trials were carried out by placing field-collected seeds in a thermogradient table set at constant temperatures of 11.7 to 41.7 C. Germination was assessed daily for 30 d, and the whole experiment was repeated a month later. Using probit regression analysis, thermal time to median germination [θT(50)], base temperature for germination (Tb), and SD of thermal times for germination [σθT(50)] were estimated from germination data, and model parameters were derived using the Solver tool in Microsoft Excel®. Germination rates increased linearly below the estimated optimum temperatures of 33.5 to 36 C. Estimated Tb averaged 16.7 C, whereas θT(50) equaled 17.1 degree-days and σθT(50) was only 0.1 degree-day. The estimated Tb for smallflower umbrella sedge is remarkably higher than that of japonica and indica types of rice, as well as Tb of important weeds in the Echinochloa complex. Relative to the latter, smallflower umbrella sedge has lower thermal-time requirements to germination and greater germination synchronicity. However, it would also initiate germination much later because of its higher Tb, given low soil temperatures early in the rice growing season in California. When integrated into weed growth models, these results might help optimize the timing and efficacy of smallflower umbrella sedge control measures.
Cognitive deficits in depressed adults may reflect impaired decision-making. To investigate this possibility, we analyzed data from unmedicated adults with Major Depressive Disorder (MDD) and healthy controls as they performed a probabilistic reward task. The Hierarchical Drift Diffusion Model (HDDM) was used to quantify decision-making mechanisms recruited by the task, to determine if any such mechanism was disrupted by depression.
Data came from two samples (Study 1: 258 MDD, 36 controls; Study 2: 23 MDD, 25 controls). On each trial, participants indicated which of two similar stimuli was presented; correct identifications were rewarded. Quantile-probability plots and the HDDM quantified the impact of MDD on response times (RT), speed of evidence accumulation (drift rate), and the width of decision thresholds, among other parameters.
RTs were more positively skewed in depressed v. healthy adults, and the HDDM revealed that drift rates were reduced—and decision thresholds were wider—in the MDD groups. This pattern suggests that depressed adults accumulated the evidence needed to make decisions more slowly than controls did.
Depressed adults responded slower than controls in both studies, and poorer performance led the MDD group to receive fewer rewards than controls in Study 1. These results did not reflect a sensorimotor deficit but were instead due to sluggish evidence accumulation. Thus, slowed decision-making—not slowed perception or response execution—caused the performance deficit in MDD. If these results generalize to other tasks, they may help explain the broad cognitive deficits seen in depression.
This Element introduces the concept of institutional weakness, arguing that weakness or strength is a function of the extent to which an institution actually matters to social, economic or political outcomes. It then presents a typology of three forms of institutional weakness: insignificance, in which rules are complied with but do not affect the way actors behave; non-compliance, in which state elites either choose not to enforce the rules or fail to gain societal cooperation with them; and instability, in which the rules are changed at an unusually high rate. The Element then examines the sources of institutional weakness.
Using existing data from clinical registries to support clinical trials and other prospective studies has the potential to improve research efficiency. However, little has been reported about staff experiences and lessons learned from implementation of this method in pediatric cardiology.
We describe the process of using existing registry data in the Pediatric Heart Network Residual Lesion Score Study, report stakeholders’ perspectives, and provide recommendations to guide future studies using this methodology.
The Residual Lesion Score Study, a 17-site prospective, observational study, piloted the use of existing local surgical registry data (collected for submission to the Society of Thoracic Surgeons-Congenital Heart Surgery Database) to supplement manual data collection. A survey regarding processes and perceptions was administered to study site and data coordinating center staff.
Survey response rate was 98% (54/55). Overall, 57% perceived that using registry data saved research staff time in the current study, and 74% perceived that it would save time in future studies; 55% noted significant upfront time in developing a methodology for extracting registry data. Survey recommendations included simplifying data extraction processes and tailoring to the needs of the study, understanding registry characteristics to maximise data quality and security, and involving all stakeholders in design and implementation processes.
Use of existing registry data was perceived to save time and promote efficiency. Consideration must be given to the upfront investment of time and resources needed. Ongoing efforts focussed on automating and centralising data management may aid in further optimising this methodology for future studies.
Disarticulated human remains were recovered from a first-century fort ditch at Vindolanda on the north-west frontier of the Roman Empire. Ancient DNA analysis revealed the skeleton to be that of a male individual and forensic taphonomic analysis suggested a primary deposition of the body in a waterlogged environment with no obvious evidence of formal burial. Occurrences of disarticulated human remains outside a cemetery context are often overlooked in Roman bioarchaeology. This discovery adds to the growing body of literature regarding alternative funerary practice in the Empire, highlighting that the concept of burial and disposal of the dead is more complex than ancient historical sources suggest. Details of the DNA analysis are provided in the Supplementary Material available at https://doi.org/10.1017/S0068113X1900014X.
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.
To bring together stakeholders in the United Kingdom to establish national priorities for research in single-ventricle heart conditions.
This study comprised two surveys and a workshop. The initial public online survey asked respondents up to three questions they would like answered for research. Responses were classified as unanswered, already answered, or unable to be answered by scientific research. In the follow-up survey, unanswered questions were divided into categories and respondents were asked to rank categories and questions by priority. A stakeholder workshop attended by patients, parents, healthcare professionals, researchers, and charities was held to determine the final list of research priorities.
A total of 128 respondents posed 344 research questions, of which 271 were classified as unanswered, and after removing duplicates, 204 questions remained, which were divided into 20 categories. In the second survey, 56 (49.1%) respondents successfully ranked categories and questions. A total of 39 participants attended the workshop, drawing up a list of 30 research priorities across nine priority categories. The nine priority categories are: Associated co-morbidities; Brain & neurodevelopment; Exercise; Fontan failure; Heart function; Living with a single ventricle heart condition; Management of the well-functioning Fontan circulation; Surgery & perioperative care; and Transplantation, mechanical support & novel therapies.
Through a multi-stage process, we engaged a wide range of interested parties to establish a list of research priorities in single-ventricle heart conditions. This provides a platform for clinicians, researchers, and funders in the United Kingdom and elsewhere to address the most important questions and improve outcomes in these rare but high-impact CHDs.
The Fontan operation is a palliative surgical procedure for patients whose hearts cannot support a biventricular circulation. The haemodynamic changes that occur in pregnancy are particularly challenging for Fontan patients and the outcomes are variable. We present a case where fetal outcome was particularly poor despite a lack of high risk features pre-pregnancy.
Dementia is a leading cause of morbidity and mortality without pharmacologic prevention or cure. Mounting evidence suggests that adherence to a Mediterranean dietary pattern may slow cognitive decline, and is important to characterise in at-risk cohorts. Thus, we determined the reliability and validity of the Mediterranean Diet and Culinary Index (MediCul), a new tool, among community-dwelling individuals with mild cognitive impairment (MCI). A total of sixty-eight participants (66 % female) aged 75·9 (sd 6·6) years, from the Study of Mental and Resistance Training study MCI cohort, completed the fifty-item MediCul at two time points, followed by a 3-d food record (FR). MediCul test–retest reliability was assessed using intra-class correlation coefficients (ICC), Bland–Altman plots and κ agreement within seventeen dietary element categories. Validity was assessed against the FR using the Bland–Altman method and nutrient trends across MediCul score tertiles. The mean MediCul score was 54·6/100·0, with few participants reaching thresholds for key Mediterranean foods. MediCul had very good test–retest reliability (ICC=0·93, 95 % CI 0·884, 0·954, P<0·0001) with fair-to-almost-perfect agreement for classifying elements within the same category. Validity was moderate with no systematic bias between methods of measurement, according to the regression coefficient (y=−2·30+0·17x) (95 % CI −0·027, 0·358; P=0·091). MediCul over-estimated the mean FR score by 6 %, with limits of agreement being under- and over-estimated by 11 and 23 %, respectively. Nutrient trends were significantly associated with increased MediCul scoring, consistent with a Mediterranean pattern. MediCul provides reliable and moderately valid information about Mediterranean diet adherence among older individuals with MCI, with potential application in future studies assessing relationships between diet and cognitive function.
Jumping to conclusions (JTC), which is the proneness to require less information before forming beliefs or making a decision, has been related to formation and maintenance of delusions. Using data from the National Institute of Health Research Biomedical Research Centre Genetics and Psychosis (GAP) case–control study of first-episode psychosis (FEP), we set out to test whether the presence of JTC would predict poor clinical outcome at 4 years.
One-hundred and twenty-three FEP patients were assessed with the Positive and Negative Syndrome Scale (PANSS), Global Assessment of Functioning (GAF) and the probabilistic reasoning ‘Beads’ Task at the time of recruitment. The sample was split into two groups based on the presence of JTC bias. Follow-up data over an average of 4 years were obtained concerning clinical course and outcomes (remission, intervention of police, use of involuntary treatment – the Mental Health Act (MHA) – and inpatient days).
FEP who presented JTC at baseline were more likely during the follow-up period to be detained under the MHA [adjusted OR 15.62, 95% confidence interval (CI) 2.92–83.54, p = 0.001], require intervention by the police (adjusted OR 14.95, 95% CI 2.68–83.34, p = 0.002) and have longer admissions (adjusted IRR = 5.03, 95% CI 1.91–13.24, p = 0.001). These associations were not accounted for by socio-demographic variables, IQ and symptom dimensions.
JTC in FEP is associated with poorer outcome as indicated and defined by more compulsion police intervention and longer periods of admission. Our findings raise the question of whether the implementation of specific interventions to reduce JTC, such as Metacognition Training, may be a useful addition in early psychosis intervention programmes.
Important Bird and Biodiversity Areas (IBAs) are sites identified as being globally important for the conservation of bird populations on the basis of an internationally agreed set of criteria. We present the first review of the development and spread of the IBA concept since it was launched by BirdLife International (then ICBP) in 1979 and examine some of the characteristics of the resulting inventory. Over 13,000 global and regional IBAs have so far been identified and documented in terrestrial, freshwater and marine ecosystems in almost all of the world’s countries and territories, making this the largest global network of sites of significance for biodiversity. IBAs have been identified using standardised, data-driven criteria that have been developed and applied at global and regional levels. These criteria capture multiple dimensions of a site’s significance for avian biodiversity and relate to populations of globally threatened species (68.6% of the 10,746 IBAs that meet global criteria), restricted-range species (25.4%), biome-restricted species (27.5%) and congregatory species (50.3%); many global IBAs (52.7%) trigger two or more of these criteria. IBAs range in size from < 1 km2 to over 300,000 km2 and have an approximately log-normal size distribution (median = 125.0 km2, mean = 1,202.6 km2). They cover approximately 6.7% of the terrestrial, 1.6% of the marine and 3.1% of the total surface area of the Earth. The launch in 2016 of the KBA Global Standard, which aims to identify, document and conserve sites that contribute to the global persistence of wider biodiversity, and whose criteria for site identification build on those developed for IBAs, is a logical evolution of the IBA concept. The role of IBAs in conservation planning, policy and practice is reviewed elsewhere. Future technical priorities for the IBA initiative include completion of the global inventory, particularly in the marine environment, keeping the dataset up to date, and improving the systematic monitoring of these sites.
Many agrowastes are being used for energy production by combustion in power plants. This process generates huge amounts of ash, which has a potential pozzolanic activity for blending with Portland cement or hydrated lime. In this paper, the ash obtained from elephant grass (Pennisetum purpureum Schum var. purple) leaves (EGLs) was studied, including the silicon content and its distribution, the presence of other compounds, and in addition, the presence of silica bodies (phytoliths). Combustion temperatures of 450 and 650°C produced an unaltered inorganic skeleton (spodogram), whereas at 850°C, there is a sintering process because of high potassium content in the ash. Phytoliths and different types of hairs were identified, and they contained high percentages of silica. Magnesium (mainly as periclase) was distributed in the most porous parts in the interior of the leaves. The silica can react with calcium hydroxide (pozzolanic reaction) forming calcium silicate hydrates (observed by field-emission scanning electron microscopy and thermogravimetric analysis). Fixed lime percentages at 28 curing days (63%) indicated the high reactivity of EGL ashes in calcium hydroxide pastes due to the pozzolanic reaction. This study demonstrates the possibility of the reuse of ashes from EGLs for the production of environmental-friendly cements.