Reconciling transport models across scales: the role of volume exclusion

Diffusive transport is a universal phenomenon, throughout both biological and physical sciences, and models of diffusion are routinely used to interrogate diffusion-driven processes. However, most models neglect to take into account the role of volume exclusion, which can significantly alter diffusive transport, particularly within biological systems where the diffusing particles might occupy a significant fraction of the available space. In this work we use a random walk approach to provide a means to reconcile models that incorporate crowding effects on different spatial scales. Our work demonstrates that coarse-grained models incorporating simplified descriptions of excluded volume can be used in many circumstances, but that care must be taken in pushing the coarse-graining process too far

Residential fire detection

"Residential fires have become a significant problem throughout the U.S. The National Fire Protection Association (NFPA) estimates that in 1982 residential fires in the U.S. killed 4,940 persons and resulted in injury to 21,100 more. In addition, these residential fires accounted for an estimated $3,253,000,000 in property damage. Figure 1 shows the causes of residential fires as reported by the Federal Emergency Management Agency in its National Fire Incident Reporting System. The leading causes of fires in one-and-two family dwellings were heating (31 percent), cooking (15 percent), and incendiary or suspicious (10 percent). In residential properties, cigarettes are still the leading cause of accidental multiple death fires (those fires that are fatal to three or more persons) by a factor of two to one. Fires resulting from fixed or portable heating equipment-woodstoves, kerosene heaters, gas or electric cooking stoves, etc.,-are the second most common cause of accidental multipledeath fires in residential properties."--First page.David E. Baker (Department of Agricultural Engineering, College of Agriculture) and Paul Adams (Director, Missouri Fire and Rescue Training Institute, University of Missouri--Columbia)Revised 8/84/10

Theorising how art gallery interventions impact people with dementia and their caregivers

Dementia refers to a variety of diseases that are characterised by cognitive difficulties and an overall decline in daily living skills. Psychologically-informed arts and health programmes may be particularly beneficial ways of improving the lives of people with dementia and their caregivers. This study sought to better understand how programmes at contemporary and traditional art galleries might play a role in the lives of people with dementia. Participants included 12 people with mild to moderate dementia, their 12 caregivers and 4 gallery facilitators. Those with dementia and their caregivers were engaged in art-viewing followed by art-making over an 8 week period. Data, collected through post-intervention interviews with participants, field notes and extensive written communication between the facilitators and research team, were analysed using grounded theory methodology to theorise how gallery-based interventions affect people with dementia and those who care for them. The emerging theory has four primary components: the art gallery is seen as being a physically-valued place that provides intellectual stimulation and offers opportunities for social inclusion that can change how dementia is perceived. These components coalesced to create positive emotional and relational effects for those with dementia and caregivers. The resulting theory has potential implications for the use of gallery-based programmes in dementia care within public health, healthcare and museum/art gallery policy and practice

CONTRACT INCENTIVES AND EXCESSIVE NITROGEN USE IN AGRICULTURE

This study examines incentives for input use under tournament contracts. We analyze implications of contract design for nitrate-based environmental externalities generated by agricultural producers. Outcomes are compared from contracts awarded by tournament to those from fixed-payment contracts. Our findings show contract insecurity can distort input use. The model developed in this analysis is applied to a region of the U.S. where tournament-based production is prevalent and groundwater contamination is a problem. We find contract insecurity increases nitrogen use by about 12%, resulting in a 17% increase in nitrate leaching. Implications for contract modification to reduce environmental externalities while maintaining contract incentives are discussed.Crop Production/Industries,

Cognitive impairment and decline in cognitively normal older adults with high amyloid-β: A meta-analysis

AbstractIntroductionThis meta-analysis aimed to characterize the nature and magnitude of amyloid (Aβ)-related cognitive impairment and decline in cognitively normal (CN) older individuals.MethodMEDLINE Ovid was searched from 2012 to June 2016 for studies reporting relationships between cerebrospinal fluid or positron emission tomography (PET) Aβ levels and cognitive impairment (cross-sectional) and decline (longitudinal) in CN older adults. Neuropsychological data were classified into domains of episodic memory, executive function, working memory, processing speed, visuospatial function, semantic memory, and global cognition. Type of Aβ measure, how Aβ burden was analyzed, inclusion of control variables, and clinical criteria used to exclude participants, were considered as moderators. Random-effects models were used for analyses with effect sizes expressed as Cohen's d.ResultsA total of 38 studies met inclusion criteria contributing 30 cross-sectional (N = 5005) and 14 longitudinal (N = 2584) samples. Aβ-related cognitive impairment was observed for global cognition (d = 0.32), visuospatial function (d = 0.25), processing speed (d = 0.18), episodic memory, and executive function (both d's = 0.15), with decline observed for global cognition (d = 0.30), semantic memory (d = 0.28), visuospatial function (d = 0.25), and episodic memory (d = 0.24). Aβ-related impairment was moderated by age, amyloid measure, type of analysis, and inclusion of control variables and decline moderated by amyloid measure, type of analysis, inclusion of control variables, and exclusion criteria used.DiscussionCN older adults with high Aβ show a small general cognitive impairment and small to moderate decline in episodic memory, visuospatial function, semantic memory, and global cognition

Boston University Medical Center: Perspectives on Health Policy

Report of a symposium held at the Boston University Medical Center

Total Value of Phosphorus Recovery

Phosphorus (P) is a critical, geographically concentrated, nonrenewable resource necessary to support global food production. In excess (e.g., due to runoff or wastewater discharges), P is also a primary cause of eutrophication. To reconcile the simultaneous shortage and overabundance of P, lost P flows must be recovered and reused, alongside improvements in P-use efficiency. While this motivation is increasingly being recognized, little P recovery is practiced today, as recovered P generally cannot compete with the relatively low cost of mined P. Therefore, P is often captured to prevent its release into the environment without beneficial recovery and reuse. However, additional incentives for P recovery emerge when accounting for the total value of P recovery. This article provides a comprehensive overview of the range of benefits of recovering P from waste streams, i.e., the total value of recovering P. This approach accounts for P products, as well as other assets that are associated with P and can be recovered in parallel, such as energy, nitrogen, metals and minerals, and water. Additionally, P recovery provides valuable services to society and the environment by protecting and improving environmental quality, enhancing efficiency of waste treatment facilities, and improving food security and social equity. The needs to make P recovery a reality are also discussed, including business models, bottlenecks, and policy and education strategies

Residential fire detection (1993)

Reviewed October 1993

Psychopathology and cognitive performance in individuals with membrane-associated guanylate kinase mutations: a functional network phenotyping study.

BACKGROUND: Rare pathogenic variants in membrane-associated guanylate kinase (MAGUK) genes cause intellectual disability (ID) and have recently been associated with neuropsychiatric risk in the non-ID population. However, it is not known whether risk for psychiatric symptoms amongst individuals with ID due to MAGUK gene mutations is higher than expected for the degree of general intellectual impairment, nor whether specific cognitive differences are associated with disruption to this gene functional network. METHODS: This study addresses these two questions via behavioural questionnaires and cognitive testing, applying quantitative methods previously validated in populations with ID. We compared males with X-linked ID caused by mutations in three MAGUK genes (PAK3, DLG3, OPHN1; n = 9) to males with ID caused by mutations in other X chromosome genes (n = 17). Non-parametric and parametric analyses were applied as appropriate to data. RESULTS: Groups did not differ in age, global cognitive impairment, adaptive function or epilepsy prevalence. However, individuals with MAGUK gene mutations demonstrated significantly higher psychopathology risks, comprising elevated total problem behaviours, prominent hyperactivity and elevated scores on an autism screening checklist. Despite these overt difficulties, individuals in the MAGUK group performed more accurately than expected for age and intelligence quotient (IQ) on computerised tests of visual attention, convergent with mouse models of MAGUK loss-of-function. CONCLUSIONS: Our findings support a role for MAGUK genes in influencing cognitive parameters relevant to psychiatric risk. In addition to establishing clear patterns of impairment for this group, our findings highlight the importance of careful phenotyping after genetic diagnosis, showing that gene functional network disruptions can be associated with specific psychopathological risks and cognitive differences within the context of ID.We thank all study participants and their families for extensive contributions to this project. This study was funded by the Academy of Medical Sciences/Wellcome Trust via a Starter Grant for Clinical Lecturers to KB. KB is funded by a National Institute for Health Research Academic Clinical Lectureship. GS is funded by a Wellcome Trust project grant and a James S. McDonnell Foundation Understanding Human Cognition Scholar Award. DEA is funded by an MRC UK intramural programme (MC-A0606-5PQ41). FLR is funded by the National Institute for Health Research (Cambridge Biomedical Research Centre).This is the final version of the article. It first appeared from BioMed Central via http://dx.doi.org/10.1186/s11689-015-9105-

The natural history of renal disease in Australian Aborigines. Part 1. Changes in albuminuria and glomerular filtration rate over time

The natural history of renal disease in Australian Aborigines. Part 1. Changes in albuminuria and glomerular filtration rate over time.BackgroundThe purpose of this study was to describe changes over time in albuminuria and glomerular filtration rate (GFR) in a cohort of Australian Aborigines from a community with high rates of renal disease and renal failure.MethodsParticipants were 486 adult community members (20+ years at first exam) who were screened for renal disease and related factors on at least two occasions (mean 2.7 occasions), at least a year apart, between 1990 and 1997. Renal function was assessed by the albumin:creatinine ratio (ACR; g/mol) on a random urine specimen and by the GFR estimated from the Cockcroft-Gault formula. Evolution over time was expressed as the average annual changes in these parameters.ResultsOn baseline examination, 70% of participants had albuminuria (ACR 1.1+ g/mol) There was a significant net increase in ACR and a fall in GFR in the cohort over time. Among individuals, however, changes were strongly correlated with ACR levels at baseline. There was no loss of GFR in persons with normal renal parameters at baseline and a rapid loss of GFR in those with substantial levels of albuminuria at baseline. Other factors significantly correlated with progression of ACR included age, baseline body mass index and systolic blood pressure, the presence of diabetes (or levels of fasting glucose), and elevated levels of serum gamma glutamyl transferase. Factors significantly associated with loss of GFR included body mass index, diabetes, systolic and diastolic blood pressures, microscopic hematuria, and marginally high cholesterol levels.ConclusionAlbuminuria progresses and GFR is lost over time in individuals in this community, at rates that are strongly dependent on levels of pre-existing albuminuria. Much loss of GFR and all renal failure should be avoided by preventing the development of albuminuria and minimizing its progression. This depends on improving the weight, blood pressure, and metabolic profile of the entire community and reducing infections. Modification of the course in people with established disease depends on vigorous control of blood pressure and the metabolic profile and the specific use of angiotensin-converting enzyme inhibitors