To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure no-reply@cambridge.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Preferences for charitable giving in auctions can be modeled by assuming that bidders receive additional utility proportional to the revenue raised by an auctioneer. The theory of bidding in the presence of such preferences results in a very counterintuitive prediction which is that, in many cases, bidders having preferences for charitable giving does not lead to a substantial revenue advantage for an auctioneer. We test this theory and this prediction with a series of experiments. In one experiment we induce charitable preferences exactly as specified in the model to see if bidders respond to them as predicted. We find that they do. We then conduct a second experiment in which the revenue from the auctions is donated to actual charities to verify the robustness of the prediction when charitable preferences are generated by a more natural source and find again that the theoretical prediction holds: even strong charitable preferences do not result in substantial revenue increases to the auctioneer.
Many social dilemmas involve deciding among alternative public goods, and include cases where part of the population may dislike a particular option. In such cases, an agent may want to spend resources to oppose or reduce the provision of the option they don’t like. We propose the generalized voluntary contributions mechanism (GVCM), which allows allocating resources to increase or decrease the level of public good. Our main treatment variables include two versions of the GVCM (uncensored, or censored at positive provision). We study performance of GVCM for various compositions of the polarized preferences. We find that uncensoring the mechanism does not impose net efficiency costs and leads to more diversity in the provision of the public good. The nature of efficiency loss is more complex compared to standard VCM and is not driven by free riding.
Goods are said to be combinatorial when the value of a bundle of goods is not equal to the sum of the values of the same goods unbundled. Investigations of combinatorial allocation problems should recognize that there are two separate aspects of such problems: an environmental distinction between multiple-unit allocation problems which involve combinatorial goods and those which do not do so, and an institutional distinction between auctions in which combinatorial values can be expressed as part of the bidding rules and those in which they cannot. Forsythe and Isaac (Research in Experimental Economics, Vol. 2 (1982). Greenwich, Conn.: JAI Press, Inc.) reports the extension of the Vickrey auction into a demand-revealing, multiple unit, private goods auction that can incorporate combinatorial values. This current paper places that theoretically demand-revealing institution in a series of experimental environments in order to generate results (e.g. efficiencies) which may serve as a benchmark for other auctions (combinatorial or otherwise) whose implementation characteristics may be more favorable. To aid in interpretation of our Vickrey experimental results, we also provide results of alternatives to Vickrey allocations from both institutional and heuristic sources, as well as a discussion of the source of the Vickrey auctions high efficiencies even in the presence of misrevelation.
We present an experimental design where uncertainty is generated from the advice of experts with conflicts of interest. In this experiment clients are faced with a variant of a multi-armed bandit problem with a random end-time. On the known arm (the “task screen”), clients can earn a certain payment per completion of a decoding task. However, clients may also opt for the unknown arm where they earn an uncertain amount if they end the experiment on this “expert screen”. The amount is uncertain to the clients because the value is being communicated through an “expert” with conflicted incentives. A control session provides for direct transmission of the value to the clients. Our results show that ambiguity aversion is alive-and-well in this environment. Also, when we vary the wage rate on the known arm we find that higher opportunity cost clients are less likely to heed the advice of conflicted experts.
Experiments are reported that add to the growing literature on the voluntary provision of public goods. Information conditions are manipulated to address whether early findings of above-equilibrium contributions to a public good are a result of complete information regarding the symmetry of the game. No significant information effect was found. Further, by examining designs with an interior Nash equilibrium, this research suggests that the nonzero contributions observed in the previous dominant strategy environments, where the prediction was a zero level of provision of the public good, were not simply transitional errors as the system converged to a boundary equilibrium.
We investigated the hypothesis that supplementing milk replacer (MR) with exogenous lactoferrin (LF) would improve average daily gain (ADG) and feed efficiency and decrease scouring incidence in dairy calves. Lactoferrin is an antimicrobial and anti-inflammatory glycoprotein naturally found in bovine colostrum and milk that is low in MR. Previous studies suggest that supplementing LF to MR enhances ADG and feed efficiency while reducing disease occurrence in pre-weaning dairy calves. In our experiment, 103 Holstein heifer calves were randomly assigned to 1 of 4 treatments in a randomized complete block design from birth to d56 of age. Each calf received 340.1 g/d of 24% protein, 20% fat basal MR fed twice daily from d1 to 42 and once daily from d43 to 49, supplemented with 0 (L0), 1 (L1), 2 (L2) or 4 (L4) g/hd/d of LF treatment (45% purity). Calves were weaned at 49d of age. Body weight was measured at d1, 14, 28, 42, 49 and 56 of age. Faecal scores were measured weekly. Milk replacer and calf starter intake was measured daily and calculated biweekly. Data were analyzed using a linear mixed model with fixed effects of LF inclusion, and random effects of source herd and nursery room. In the first two weeks of life, ADG and gain-to-feed ratio (G:F) were numerically (non-statistically) increased in L4 tended compared with L1 and L2, but this effect was not maintained throughout the rest of the pre-weaning period or entire experiment. Average faecal score during the entire 56d experiment was greater in L2 compared with L0, L1 and L4, although faecal scores of all treatment groups were generally low. Under the conditions of the present study, LF supplementation at the inclusion levels provided showed minimal effects on feed intake, growth rate or calf health.
OBJECTIVES/GOALS: Susceptible mucocutaneous membranes of the eye and nasal cavity are easily infected by viruses leading to pink eye or respiratory infections whose direct cost has been estimated as $16 billion annually in the United States. We have developed a novel and effective barrier that will be agnostic to variants enveloped viruses like coronaviruses. METHODS/STUDY POPULATION: We evaluated the efficacy of hydroxypropyl cyclodextrin barrier in preventing respiratory coronavirus infections using 25 humanized angiotensin converting enzyme-2 receptor (hACE-2) mice under a BSL3 laboratory setting. We have shown the barrier is safe and efficacious in preventing coronavirus infections in in vitro respiratory cell lines. We instilled 10 uL aliquot of the barrier into the nostril of the mouse 30 minutes before exposing them to a 10uL titer containing 10,000 plaque forming units of the SARS-CoV-2 delta variant. The control mice received the SARS-CoV-2 infection but not the barrier. The mice were observed for 5 days after which they were sacrificed. We analyzed the lungs and nasal palates for viral load using reverse transcription-polymerase chain reaction. RESULTS/ANTICIPATED RESULTS: We observed our barrier to be effective in preventing SARS-CoV-2 delta variant infection in hACE2 mice models. The lungs and nasal secretions of treated mice were less infectious with lower viral load than the control mice. The lungs of treated mice showed decrease in IFN gene expression and many cytokines and chemokines that regulate virally induced inflammatory responses such as IL-1b, IL-8, CXCL9, CXCL10, and the CCLs. We observed the plasma Angiotensin I and Angiotensin II decreased with barrier treatment, correlating with the viral load observed in the lungs. These peptides may be useful biomarkers for monitoring viral load within the lungs of virally infected individuals. DISCUSSION/SIGNIFICANCE: This supports the barrier’s efficacy to reduce transmission and prevent infections of SARS-CoV-2. This easy to use barrier can augment the mucocutaneous layers of the eye and nasal cavity. Our agnostic barrier will reduce the economic and public health burden of seasonal respiratory and eye viral infections and their related deaths amongst the public.
Aviation passenger screening has been used worldwide to mitigate the translocation risk of SARS-CoV-2. We present a model that evaluates factors in screening strategies used in air travel and assess their relative sensitivity and importance in identifying infectious passengers. We use adapted Monte Carlo simulations to produce hypothetical disease timelines for the Omicron variant of SARS-CoV-2 for travelling passengers. Screening strategy factors assessed include having one or two RT-PCR and/or antigen tests prior to departure and/or post-arrival, and quarantine length and compliance upon arrival. One or more post-arrival tests and high quarantine compliance were the most important factors in reducing pathogen translocation. Screening that combines quarantine and post-arrival testing can shorten the length of quarantine for travelers, and variability and mean testing sensitivity in post-arrival RT-PCR and antigen tests decrease and increase with the greater time between the first and second post-arrival test, respectively. This study provides insight into the role various screening strategy factors have in preventing the translocation of infectious diseases and a flexible framework adaptable to other existing or emerging diseases. Such findings may help in public health policy and decision-making in present and future evidence-based practices for passenger screening and pandemic preparedness.
OBJECTIVES/GOALS: To identify an electroencephalographic (EEG) signature of SOR in adults with TS METHODS/STUDY POPULATION: We will recruit 60 adults with CTD and 60 sex- and age-matched healthy controls to complete scales assessing severity of SOR (Sensory Gating Inventory, SGI), tics, and psychiatric symptoms. Subjects will then be monitored on dense-array scalp EEG during sequential auditory and tactile sensory gating paradigms, as such paradigms have been shown to correlate with self-report measures of SOR in other populations. Single-trial EEG data will be segmented into 100-ms epochs and spectrally deconvoluted into standard frequency bands (delta, theta, alpha, beta, gamma) for pre-defined regions of interest. We will conduct between-group contrasts (Wilcoxon rank-sum) of band-specific sensory gating indices and within-group correlations (Spearman rank correlations) between sensory gating indices and SGI scores. RESULTS/ANTICIPATED RESULTS: We hypothesize that, relative to controls, adults with CTD exhibit impaired sensory gating and that extent of impairment correlates with severity of SOR. 14 adults with CTD (9 men, 5 women) and 16 controls (10 men, 6 women) have completed the protocol to date. Within this sample, adults with CTD showed significantly reduced sensory gating compared to controls in frontal (CTD median 0.12 dB (interquartile range -0.15–0.70 dB); control -0.37 dB (-0.80–-0.13 dB); p = 0.01) and parietal (CTD 0.17 dB (-0.08–0.50 dB); control -0.20 dB (-0.43–0.10 dB); p = 0.01) gamma band during the 100-200 ms epoch in the tactile paradigm. No significant between-group differences were evident for the auditory paradigm. Among adults with CTD, multiple sensory gating indices significantly correlated with SGI scores. Enrollment continues. DISCUSSION/SIGNIFICANCE: Results aim to clarify the extent of sensory gating impairment in TS and identify a clinical correlate of neurophysiologic dysfunction in the disorder. Such knowledge has direct implications for identification of candidate neurophysiologic biomarkers, an express goal of the National Institutes of Health.
The pandemic has put a huge strain on people’s mental health, with varying restrictions affecting people’s lives. Little is known how the pandemic affects older adults’ mental health, particularly those living in low- and middle-income countries (LMICs) where restrictions are affecting people’s access to basic necessities. Thus, the aim of this 3-country study was to understand the long- term impacts of the pandemic on the mental well-being of older adults with and without dementia in LMICs.
Methods:
We are collecting 30 baseline and 15 follow-up interviews with older adults (aged 60+), people with dementia, and family carers in Colombia, India, and Uganda, as well as a baseline and follow-up focus group with health and social are professionals in each country. Interviews are conducted remotely over the phone due to pandemic restrictions, with data collection taking place between March and July 2021. Transcripts are translated into English before being analysed using thematic analysis.
Results:
To date, we have completed close to 90 baseline interviews and 3 focus groups with health and social care professionals. Analysis is ongoing, but findings are capturing the detrimental second wave in India and follow-up interviews will capture the longitudinal impacts on mental health.
Conclusions:
Whilst vaccines are starting to be rolled out in LMICs, albeit at different rates, the virus will likely take much longer to be somewhat managed in LMICs. This leaves more room for people’s physical as well as mental health to be impacted by the restrictions, and with often limited mental health service coverage, it is all the more important o understand the impact of the pandemic on older people’s mental health.
Though there are effective psychological and drug treatments for obsessive–compulsive disorder (OCD), many patients remain inadequately treated or untreated. Making effective self-treatment guidance available may increase the number of patients being helped. In this review, database and manual literature searches were performed of case studies, open and randomised controlled trials (RCTs) of bibliotherapy, self-help groups, telecare and computer-aided self-help for OCD. We found no RCTs of bibliotherapy or self-help groups for OCD. Three open studies showed the efficacy of brief exposure and ritual prevention (ERP) instructions delivered by a live therapist by phone. A vicarious ERP computer program was effective in a small open study. Fully interactive computer-aided self-help by ERP for OCD was efficacious in two open studies and a large multicentre RCT, and in a small RCT compliance and outcome with that program was enhanced by brief scheduled support from a clinician. Although more research is needed, self-help approaches have the potential to help many more patients who would otherwise remain inadequately treated or untreated. Their dissemination could save resources used by health care providers. We propose a stepped care model for the treatment of OCD.
Mesoporous silicas were synthesized via a surfactant-templated sol-gel route using castor oil as the templating agent under acidic medium. The resulting silicas were subsequently amine functionalized with 3-aminopropyltriethoxysilane (NH2-MTS), [3-(2-aminoethylamino)-propyl]trimethoxysilane (NN-MTS), and [3-(diethylamino)propyl]trimethoxysilane(DN-MTS) to introduce surface basicity. Surface physicochemical properties were characterized by field emission gun scanning electron microscopy (FEGSEM), nitrogen porosimetry, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and diffuse reflectance infrared fourier transform spectroscopy (DRIFTS). As-synthesised materials exhibit type IV adsorption-desorption isotherms characteristic of mesoporous structures. Clusters of spherical shaped materials were observed by FEGSEM, suggesting growth of silica occurs within colloidal dispersions. High-resolution N 1s XP spectra and DRIFT spectra confirmed the presence of amine groups in the organo-amine functionalised mesoporous silicas. The amine functionalised mesoporous silicas were active for the transesterification of tributyrin with methanol, with conversion found to increase from NH2-MTS< NN-MTS< DN-MTS.
Application of chlorimuron and imazaquin at 0.28 kg ai/ha to field-grown sicklepod at early bloom and early fruit stages in 1984 and 1985 almost eliminated seed production. In addition, none of the seed produced following these treatments were capable of emergence during a 4-week period following acid scarification. Glyphosate applied at 0.28 kg ai/ha at early bloom decreased seed production 84% but did not affect seedling emergence in 1984, and precluded production of seed capable of emergence in 1985. Glyphosate applications at the early fruit stage reduced the number of seed that emerged 93 and 90% in 1984 and 1985, respectively. Application of 2,4-DB at 0.28 kg ai/ha and 2,4-D at 0.56 kg ai/ha at early bloom did not affect seed production or emergence in 1984 but almost eliminated production of seed capable of emergence in 1985. Applications of 2,4-DB and 2,4-D at the early fruit stage decreased the number of seed that emerged 99 and 52% in 1984 and 46 and 57% in 1985, respectively. Herbicide applications at the late fruit stage were generally less effective than earlier applications in reducing seed production and emergence.
This research was designed to determine if sethoxydim-resistant corn hybrids exhibited levels of cross-resistance to other acetyl-coenzyme A carboxylase (ACCase)-inhibiting herbicides. Three sethoxydim-resistant hybrids were tested in 1995 and four in 1996. The hybrids were treated with the 1 × (labeled use rate for annual grass control) and 4 × rate of clethodim, fenoxaprop-P plus fluazifop-P, fluazifop-P, quizalofop-P, and sethoxydim. At the 1 × rate, similar levels of corn safety were observed in both years with sethoxydim, quizalofop-P (except Asgrow RX620SR in 1995), and in 1996, fenoxaprop-P plus fluazifop-P. Corn treated with the 4 × rate of sethoxydim did not exhibit injury, while all other ACCase-inhibiting herbicides cause > 50% corn injury. Sethoxydim-resistant com hybrids used in this study did not consistently exhibit acceptable levels of cross-resistance to other ACCase-inhibiting herbicides. The use of clethodim will control volunteer sethoxydim-resistant corn in rotational crops.
Field studies were conducted in 1995 and 1996 to investigate postemergence tank mixtures of sethoxydim with various acetolactate synthase (ALS)- and non–ALS-inhibitor herbicides for weed control in sethoxydim-resistant (SR) corn. Giant foxtail control with sethoxydim was 96% and was equal to control with tank mixtures of sethoxydim plus bentazon, dicamba, dicamba plus atrazine, bromoxynil, and nicosulfuron plus bromoxynil. Giant foxtail control with sethoxydim plus atrazine, sethoxydim plus bentazon plus atrazine, and sethoxydim plus ALS-inhibiting herbicides plus 2,4-D was reduced to 60 to 89%. Common ragweed control was equal to or above 91% for tank mixtures that included bentazon plus atrazine, dicamba, dicamba plus atrazine, halosulfuron plus 2,4-D, and CGA 152005 plus primisulfuron plus 2,4-D, and the tank mixture of nicosulfuron plus bromoxynil. Common lambsquarters control was equal to or above 91% from all broadleaf herbicide treatments except bentazon and the tank mixture of halosulfuron plus 2,4-D. In these studies, only tank mixtures of sethoxydim plus dicamba or dicamba plus atrazine controlled giant foxtail, common ragweed, and common lambsquarters equal to or greater than 91% in SR corn.
Field studies were conducted in 1995 and 1996 to investigate postemergence (POST) applications of rimsulfuron (12 g ai/ha) plus thifensulfuron-methyl (6 g ai/ha) in tank-mixtures with various acetolactate synthase (ALS)- and non–ALS-inhibitor herbicides for weed control in corn. Rimsulfuron plus thifensulfuron-methyl controlled giant foxtail and common lambsquarters at least 95% but did not control common ragweed. Rimsulfuron plus thifensulfuron-methyl tank-mixed with 20 g ai/ha primisulfuron-methyl, 17 g ai/ha CGA-152005 plus 18 g ai/ha primisulfuron, 18 or 36 g ai/ha halosulfuron-methyl, 18 g ai/ha nicosulfuron, or 280 g ai/ha dicamba controlled giant foxtail at least 89%, common lambsquarters at least 96% and, with the exception of the nicosulfuron combination, controlled common ragweed at least 88%. Rimsulfuron plus thifensulfuron-methyl tank-mixed with flumetsulam (26 g ai/ha) plus clopyralid (69 g ai/ha) plus 2,4-D (140 g ai/ha), atrazine (560 g ai/ha), 2,4-D (280 g/ha), or dicamba (308 g/ha) plus atrazine (588 g/ha) reduced the control of giant foxtail to less than 78% 26 d after treatment (DAT). Corn injury was less than 12% from rimsulfuron plus thifensulfuron-methyl and from mixtures of rimsulfuron plus thifensulfuron-methyl with other herbicides except when rimsulfuron plus thifensulfuron-methyl was mixed with flumetsulam plus clopyralid plus 2,4-D. This combination injured corn 26%. In these studies the appropriate tank-mix partners for rimsulfuron plus thifensulfuron-methyl were primisulfuron, CGA-152005 plus primisulfuron, and halosufluron-methyl.
Greenhouse and laboratory experiments were conducted to investigate the response of common lambsquarters to POST applications of halosulfuron–methyl plus 2,4-D admixtures and to investigate the effects of 2,4-D on the absorption, translocation, and metabolism of halosulfuron. In the greenhouse, halosulfuron at 0, 4.5, 9, 18, and 36 g ai/ha was applied alone and mixed with 2,4-D at 0, 17, 35, and 70 g ai/ha POST to 7.5- to 9-cm seedlings, and plant fresh weights were determined 4 wk after treatment (WAT). Halosulfuron alone did not control this weed, while fresh weights of common lambsquarters treated with 2,4-D declined hyperbolically as rates increased. A synergistic response for mixtures of these herbicides occurred, as observed fresh weights for all combinations were less than expected based on independent action and the calibrated marginal responses. In the laboratory, 7.5- to 9-cm seedlings were treated POST with commercially formulated halosulfuron at 9 and 18 g/ha and 2,4-D at 0, 70, and 140 g/ha, respectively, followed by foliar-applied 14C-halosulfuron. Absorption of 14C-halosulfuron increased with time, and absorption and translocation were not influenced by the addition of 2,4-D. Results from these studies inferred that halosulfuron and 2,4-D were generally synergistic on common lambsquarters and that mechanisms other than absorption, translocation, and metabolism may explain this response.
Traumatic injuries affect millions of patients each year, and resulting post-traumatic stress disorder (PTSD) significantly contributes to subsequent impairment.
Aims
To map the distinctive long-term trajectories of PTSD responses over 6 years by using latent growth mixture modelling.
Method
Randomly selected injury patients (n = 1084) admitted to four hospitals around Australia were assessed in hospital, and at 3, 12, 24 and 72 months. Lifetime psychiatric history and current PTSD severity and functioning were assessed.
Results
Five trajectories of PTSD response were noted across the 6 years: (a) chronic (4%), (b) recovery (6%), (c) worsening/recovery (8%), (d) worsening (10%) and (e) resilient (73%). A poorer trajectory was predicted by female gender, recent life stressors, presence of mild traumatic brain injury and admission to intensive care unit.
Conclusions
These findings demonstrate the long-term PTSD effects that can occur following traumatic injury. The different trajectories highlight that monitoring a subset of patients over time is probably a more accurate means of identifying PTSD rather than relying on factors that can be assessed during hospital admission.