BT COTTON REFUGE POLICY

Since cotton producers do not own legal rights to kill insect populations that are susceptible to insecticides, individual producers may have no incentive to account for future, insecticide-resistance productivity losses arising from their pest-management decisions. As a result, the collective actions of producers may increase the rate of resistance development relative to the rate that maximizes social welfare. Concerns regarding insect-pest development of resistance to Bt cotton prompted the Environmental Protection Agency to establish legal limits on the proportion of total acres individual producers may plant, representing the first attempt to regulate the development of insecticide resistance and the first instance of the use of refuge as a policy instrument. Ever since Carlson and Castle first pointed out the resource characteristics of insecticide susceptibility, pest management in the presence of increasing resistance has been viewed as an exhaustible resource allocation problem, and many studies have examined efficient insecticide use in this setting. Resistance management studies found in the economics literature, however, have examined single-insect single-insecticide problems almost exclusively. The majority of genetic and entomological studies have followed suit. Since cotton producers routinely use multiple insecticides and insecticide mixtures to manage multiple insect pests, and since simulation and empirical evidence suggests that toxin mixtures can affect the rate of resistance development to component toxins, the standard model may not be well suited for the examination of refuge policies under cotton production settings. Static refuge policies that maximize the present value of profit flows attainable by producers over five- and 10-year planning horizons are examined using a deterministic, operational model that accounts for short- and long-run features of production and resistance development. The model accounts for the development of resistance in two cotton insect pests to Bt cotton and a popular conventional insecticide, and relationships between refuge policy, insecticide resistance, producer profit and producer behavior in Louisiana. The model is used to examine relationships between resistance simulation model parameters and refuge policies and comparative advantages between treated and untreated refuge policies.Agricultural and Food Policy,

The Minimum Clinically Important Difference on the Sleep Disorders Inventory for People with Dementia

Objectives: Sleep disturbances in dementia causes distress to people with dementia and their family carers and are associated with care home admission. The Sleep Disorders Inventory (SDI) is a validated questionnaire of sleep disturbances in dementia often used to measure treatment effectiveness, but the minimum clinically important difference (MCID) is unknown. Methods: We triangulated three investigative methods to determine the MCID of the SDI. Using data on SDI from a randomised controlled trial (RCT) with 62 participants in an intervention for sleep disorders in dementia, we (1) calculated distribution‐based values where MCID = 0.33 of a SD (SD) (2) an anchor based approach using quality of life (measured using DEMQOL‐Proxy) as an anchor. We also employed a Delphi consensus process asking 12 clinicians, sleep researchers and family carers to rate which changes on vignettes were equivalent to a MCID. Results: We found that 0.33 SD in the SDI = 4.86. Reduction in SDI total score was not significantly correlated with improvement in DEMQOL‐Proxy (Pearson's correlation = −0.01; P = 0.96) score. The Delphi consensus required two rounds to reach a consensus and concluded that changes equivalent to three points on the SDI equated to the MCID. Conclusions: Taking into account both the distribution‐based values and the Delphi process we used a whole number at the midpoint and judged the minimum clinically important difference MCID to be equal to four points. We note the clinicians and carers opinions from the Delphi process determined the MCID to be lower at three points

Becoming or remaining agitated: the course of agitation in people with dementia living in care homes: the English longitudinal Managing Agitation and Raising Quality of Life (MARQUE) study

Care home residents with dementia often have accompanying agitation. We investigated agitation’s course at 5 time-points in 1,424 people with dementia over 16 months in 86 English care homes. We categorized baseline agitation symptoms on the Cohen-Mansfield Agitation Inventory (CMAI) into none (CMAI = 29; 15%), subclinical (CMAI = 30–45; 45%), or clinically-significant (CMAI > 45; 40%). 88% of those with no agitation at baseline remained free of clinically-significant agitation at all follow-ups. Seventy percent of those exhibiting clinically-significant agitation at baseline had clinically-significant agitation at some follow-ups. Over a 16-month observation period, this study finds many care home residents with dementia never develop clinically significant agitation and interventions should be for treatment not prevention

Roll-to-roll dip coating of three different PIMs for Organic Solvent Nanofiltration

PIM-1, PIM-7, and PIM-8 composite membranes have been fabricated for Organic Solvent Nanofiltration (OSN) on two different support membranes. Both support membranes, PAN and crosslinked Ultem 1000, displayed pore sizes within the range of 20–25 nm as characterised by gas liquid porometry. PIM layers of < 500 nm thickness were formed from dip coating on a roll-to-roll pilot line. The resultant composite membranes exhibited typical MWCOs in the region of 500–800 g mol−1. The quality of coating obtained on the crosslinked Ultem 1000 support membrane was consistently higher for all three PIMs than that obtained on the PAN membrane. The PIM composite membranes coated on to crosslinked Ultem 1000 were stable in a wider range of solvents than those on the PAN support. OSN testing in a model system with isomeric alkane solutes verified that manipulated changes to the molecular architecture of the polymer backbone resulted in a higher separation factor between straight and branched alkane isomers

Passive fetal heart rate monitoring apparatus and method with enhanced fetal heart beat discrimination

An apparatus for acquiring signals emitted by a fetus, identifying fetal heart beats and determining a fetal heart rate. Multiple sensor signals are outputted by a passive fetal heart rate monitoring sensor. Multiple parallel nonlinear filters filter these multiple sensor signals to identify fetal heart beats in the signal data. A processor determines a fetal heart rate based on these identified fetal heart beats. The processor includes the use of a figure of merit weighting of heart rate estimates based on the identified heart beats from each filter for each signal. The fetal heart rate thus determined is outputted to a display, storage, or communications channel. A method for enhanced fetal heart beat discrimination includes acquiring signals from a fetus, identifying fetal heart beats from the signals by multiple parallel nonlinear filtering, and determining a fetal heart rate based on the identified fetal heart beats. A figure of merit operation in this method provides for weighting a plurality of fetal heart rate estimates based on the identified fetal heart beats and selecting the highest ranking fetal heart rate estimate

Computing a Knot Invariant as a Constraint Satisfaction Problem

We point out the connection between mathematical knot theory and spin glass/search problem. In particular, we present a statistical mechanical formulation of the problem of computing a knot invariant; p-colorability problem, which provides an algorithm to find the solution. The method also allows one to get some deeper insight into the structural complexity of knots, which is expected to be related with the landscape structure of constraint satisfaction problem.Comment: 6 pages, 3 figures, submitted to short note in Journal of Physical Society of Japa

Broadband dielectric spectroscopy on benzophenone: alpha relaxation, beta relaxation, and mode coupling theory

We have performed a detailed dielectric investigation of the relaxational dynamics of glass-forming benzophenone. Our measurements cover a broad frequency range of 0.1 Hz to 120 GHz and temperatures from far below the glass temperature well up into the region of the small-viscosity liquid. With respect to the alpha relaxation this material can be characterized as a typical molecular glass former with rather high fragility. A good agreement of the alpha relaxation behavior with the predictions of the mode coupling theory of the glass transition is stated. In addition, at temperatures below and in the vicinity of Tg we detect a well-pronounced beta relaxation of Johari-Goldstein type, which with increasing temperature develops into an excess wing. We compare our results to literature data from optical Kerr effect and depolarized light scattering experiments, where an excess-wing like feature was observed in the 1 - 100 GHz region. We address the question if the Cole-Cole peak, which was invoked to describe the optical Kerr effect data within the framework of the mode coupling theory, has any relation to the canonical beta relaxation detected by dielectric spectroscopy.Comment: 11 pages, 7 figures; revised version with new Fig. 5 and some smaller changes according to referees' demand

Protein-DNA charge transport: Redox activation of a DNA repair protein by guanine radical

DNA charge transport (CT) chemistry provides a route to carry out oxidative DNA damage from a distance in a reaction that is sensitive to DNA mismatches and lesions. Here, DNA-mediated CT also leads to oxidation of a DNA-bound base excision repair enzyme, MutY. DNA-bound Ru(III), generated through a flash/quench technique, is found to promote oxidation of the [4Fe-4S](2+) cluster of MutY to [4Fe-4S](3+) and its decomposition product [3Fe-4S](1+). Flash/quench experiments monitored by EPR spectroscopy reveal spectra with g = 2.08, 2.06, and 2.02, characteristic of the oxidized clusters. Transient absorption spectra of poly(dGC) and [Ru(phen)(2)dppz](3+) (dppz = dipyridophenazine), generated in situ, show an absorption characteristic of the guanine radical that is depleted in the presence of MutY with formation instead of a long-lived species with an absorption at 405 nm; we attribute this absorption also to formation of the oxidized [4Fe-4S](3+) and [3Fe4S](1+) clusters. In ruthenium-tethered DNA assemblies, oxidative damage to the 5'-G of a 5'-GG-3' doublet is generated from a distance but this irreversible damage is inhibited by MutY and instead EPR experiments reveal cluster oxidation. With ruthenium-tethered assemblies containing duplex versus single-stranded regions, MutY oxidation is found to be mediated by the DNA duplex, with guanine radical as an intermediate oxidant; guanine radical formation facilitates MutY oxidation. A model is proposed for the redox activation of DNA repair proteins through DNA CT, with guanine radicals, the first product under oxidative stress, in oxidizing the DNA-bound repair proteins, providing the signal to stimulate DNA repair

Passive fetal heart rate monitoring apparatus and method with enhanced fetal heart beat discrimination

An apparatus for acquiring signals emitted by a fetus, identifying fetal heart beats and determining a fetal heart rate is presented. Multiple sensor signals are outputted by a passive fetal heart rate monitoring sensor. Multiple parallel nonlinear filters filter these multiple sensor signals to identify fetal heart beats in the signal data. A processor determines a fetal heart rate based on these identified fetal heart beats. The processor includes the use of a figure of merit weighting of heart rate estimates based on the identified heart beats from each filter for each signal. The fetal heart rate thus determined is outputted to a display, storage, or communications channel. A method for enhanced fetal heart beat discrimination includes acquiring signals from a fetus, identifying fetal heart beats from the signals by multiple parallel nonlinear filtering, and determining a fetal heart rate based on the identified fetal heart beats. A figure of merit operation in this method provides for weighting a plurality of fetal heart rate estimates based on the identified fetal heart beats and selecting the highest ranking fetal heart rate estimate