7,892 research outputs found
Pest-predator spatial relationships in winter rape: implications for integrated crop management
Douglas Warner, Les J Allen-Williams, Andrew W Ferguson, and Ingrid H Williams, 'Pest–predator spatial relationships in winter rape: implications for integrated crop management', Pest Management Science, Vol. 56 (11): 977-982, November 2000, doi: 10.1002/1526-4998(200011)56:113.0.CO;2-U. Copyright © 2000 Society of Chemical IndustryThe brassica pod midge (Dasineura brassicae) is an important and widespread pest of winter and spring oilseed rape throughout Europe. Pods infested by D brassicae larvae split prematurely, releasing seeds, and the larvae drop to the soil into which they burrow to pupate. At this stage in its lifecycle D brassicae is potentially vulnerable to predation by carabid beetles foraging on the soil surface. This is the first study in the UK to focus on carabid beetles as predators of D brassicae in the oilseed rape crop. The spatio-temporal distributions of larvae of D brassicae dropping to the soil from the crop canopy and of adult carabid beetles active on the soil surface were analysed in two consecutive years. Insect samples were collected from spatially referenced sampling points across each crop. Counts of insects were mapped and analysed, and the degree of spatial association between predator and prey determined using Spatial Analysis by Distance Indices (SADIE). Carabid species abundant and active during peak drop of first generation D brassicae larvae included Agonum dorsale, Amara similata, Harpalus rufipes and Nebria brevicollis. The larvae of D brassicae had a marked edge distribution within the crop. SADIE analysis revealed significant spatial association between larvae of D brassicae and adult H rufipes (P <0.05) in 1998, but not with adults of A dorsale, A similata or N brevicollis. In 1999, there was strong spatial association only between larvae of D brassicae and adult A dorsale (P <0.01). Aggregation of N brevicollis adults occurred in some areas of greatest D brassicae larval counts in 1999, but overall spatial association was not signi®cant. The distributions are discussed in terms of their relevance to integrated crop management (ICM) strategies and spatial targeting of insecticides.Peer reviewe
Improved Bounds on the Phase Transition for the Hard-Core Model in 2-Dimensions
For the hard-core lattice gas model defined on independent sets weighted by
an activity , we study the critical activity
for the uniqueness/non-uniqueness threshold on the 2-dimensional integer
lattice . The conjectured value of the critical activity is
approximately . Until recently, the best lower bound followed from
algorithmic results of Weitz (2006). Weitz presented an FPTAS for approximating
the partition function for graphs of constant maximum degree when
where is the
infinite, regular tree of degree . His result established a certain
decay of correlations property called strong spatial mixing (SSM) on
by proving that SSM holds on its self-avoiding walk tree
where and is an ordering on the neighbors of vertex . As
a consequence he obtained that . Restrepo et al. (2011) improved Weitz's approach for
the particular case of and obtained that
. In this paper, we establish an upper bound for
this approach, by showing that, for all , SSM does not hold on
when . We also present a
refinement of the approach of Restrepo et al. which improves the lower bound to
.Comment: 19 pages, 1 figure. Polished proofs and examples compared to earlier
versio
Apparent Complete Response of a Treatment Refractory and Recurrent Squamous Cell Carcinoma Lesion to Photochemical Internalization: A Clinical Case Study
Photochemical internalisation (PCI) depends on the delivery of sub‐lethal photodynamic reaction to facilitate the work of a chemotherapeutic agent. We discuss our experience in managing a patient with extensive squamous cell carcinoma of the right face and scalp under the TPCS2a‐based bleomycin PCI treatment protocol. In this case, an 84‐year‐old Caucasian received 0.25mg/kg of TPCS2a (Amphinex®). Surface illumination photochemical internalisation was carried out after 4 days, which was preceded by the chemotherapeutic agent infusion (Bleomycin). After one week from the illumination time, tissue necrosis was evident and tumour shrinkage was most noticeable at day 14 post‐illumination. Follow‐up at 6 weeks continued to show tissue healing and regeneration with no clinical evidence of recurrence. Multiple surgical biopsies were taken at 1 and 3 months post‐illumination and found to be tumour free. PCI’s depth of effect has been very significant with negligible damage to the collateral tissues. This technology has a role in interventional oncology especially when managing challenging cases
Our Administrative System of Criminal Justice
To commemorate our founding in 1914, the Board of Editors has selected six influential pieces published by the Law Review over the past 100 years and will republish one piece in each issue.
The fourth piece selected by the Board is Our Administrative System of Criminal Justice, an article written by Gerard E. Lynch that is among the most cited works in the Law Review’s history. This article illustrates how the practice of plea bargaining blurs the boundaries between adversarial and inquisitorial criminal justice systems.
Judge Lynch now sits on the Second Circuit having eventually succeeded the late Judge Joseph M. McLaughlin, who also is honored in the pages of this book for the permanent mark he left on Fordham Law School and the Law Review. We think it is fitting that the Law Review feature two of the many contributions that judges of the Second Circuit have made to legal education and scholarship in this issue
Charge superconductivity from pair density wave order in certain high temperature superconductors
A number of spectacular experimental anomalies\cite{li-2007,fujita-2005} have
recently been discovered in certain cuprates, notably {\LBCO} and {\LNSCO},
which exhibit unidirectional spin and charge order (known as ``stripe order'').
We have recently proposed to interpret these observations as evidence for a
novel ``striped superconducting'' state, in which the superconducting order
parameter is modulated in space, such that its average is precisely zero. Here,
we show that thermal melting of the striped superconducting state can lead to a
number of unusual phases, of which the most novel is a charge
superconducting state, with a corresponding fractional flux quantum .
These are never-before observed states of matter, and ones, moreover, that
cannot arise from the conventional Bardeen-Cooper-Schrieffer (BCS) mechanism.
Thus, direct confirmation of their existence, even in a small subset of the
cuprates, could have much broader implications for our understanding of high
temperature superconductivity. We propose experiments to observe fractional
flux quantization, which thereby could confirm the existence of these states.Comment: 5 pages, 2 figures; new version in Nature Physics format with a
discussion of the effective Josephson coupling J2 and minor changes. Mildly
edited abstract. v3: corrected versio
A comparison of extremal optimization with flat-histogram dynamics for finding spin-glass ground states
We compare the performance of extremal optimization (EO), flat-histogram and
equal-hit algorithms for finding spin-glass ground states. The
first-passage-times to a ground state are computed. At optimal parameter of
tau=1.15, EO outperforms other methods for small system sizes, but equal-hit
algorithm is competitive to EO, particularly for large systems. Flat-histogram
and equal-hit algorithms offer additional advantage that they can be used for
equilibrium thermodynamic calculations. We also propose a method to turn EO
into a useful algorithm for equilibrium calculations.
Keywords: extremal optimization. flat-histogram algorithm, equal-hit
algorithm, spin-glass model, ground state.Comment: 10 LaTeX pages, 2 figure
Basal-plane Incommensurate Phases in HCP Structures
An Ising model with competing interaction is used to study the appearance of
incommensurate phases in the basal plane of an hexagonal closed-packed
structure. The calculated mean-field phase diagram reveals various
1q-incommensurate and lock-in phases. The results are applied to explain the
basal-plane incommensurate phase in some compounds of the A'A"BX_4 family, like
K_2MoO_4, K_2WO_4, Rb_2WO4 and to describe the sequence of high-temperature
phase transitions in other compounds of this family.Comment: 8 pages, RevTeX + 4 ps figure
Disulfonated tetraphenyl chlorin (TPCS2a)–induced photochemical internalisation of bleomycin in patients with solid malignancies: A first-in-man phase I dose escalation clinical trial
BACKGROUND: Photochemical internalisation, a novel minimally invasive treatment, has shown promising preclinical results in enhancing and site-directing the effect of anticancer drugs by illumination, which initiates localised chemotherapy release. We assessed the safety and tolerability of a newly developed photosensitiser, disulfonated tetraphenyl chlorin (TPCS2a), in mediating photochemical internalisation of bleomycin in patients with advanced and recurrent solid malignancies. METHODS: In this phase 1, dose-escalation, first-in-man trial, we recruited patients (aged ≥18 to <85 years) with local recurrent, advanced, or metastatic cutaneous or subcutaneous malignancies who were clinically assessed as eligible for bleomycin chemotherapy from a single centre in the UK. Patients were given TPCS2a on day 0 by slow intravenous injection, followed by a fixed dose of 15 000 IU/m2 bleomycin by intravenous infusion on day 4. After 3 h, the surface of the target tumour was illuminated with 652 nm laser light (fixed at 60 J/cm2). The TPCS2a starting dose was 0·25 mg/kg and was then escalated in successive dose cohorts of three patients (0·5, 1·0, and 1·5 mg/kg). The primary endpoints were safety and tolerability of TPCS2a; other co-primary endpoints were dose-limiting toxicity and maximum tolerated dose. The primary analysis was per protocol. This study is registered with ClinicalTrials.gov, number NCT00993512, and has been completed. FINDINGS: Between Oct 3, 2009, and Jan 14, 2014, we recruited 22 patients into the trial. 12 patients completed the 3-month follow-up period. Adverse events related to photochemical internalisation were either local, resulting from the local inflammatory process, or systemic, mostly as a result of the skin-photosensitising effect of TPCS2a. The most common grade 3 or worse adverse events were unexpected higher transient pain response (grade 3) localised to the treatment site recorded in nine patients, and respiratory failure (grade 4) noted in two patients. One dose-limiting toxicity was reported in the 1·0 mg/kg cohort (skin photosensitivity [grade 2]). Dose-limiting toxicities were reported in two of three patients at a TPCS2a dose of 1·5 mg/kg (skin photosensitivity [grade 3] and wound infection [grade 3]); thus, the maximum tolerated dose of TPCS2a was 1·0 mg/kg. Administration of TPCS2a was found to be safe and tolerable by all patients. No deaths related to photochemical internalisation treatment occurred. INTERPRETATION: TPCS2a-mediated photochemical internalisation of bleomycin is safe and tolerable. We identified TPCS2a 0·25 mg/kg as the recommended treatment dose for future trials. FUNDING: PCI Biotech
Metropolis simulations of Met-Enkephalin with solvent-accessible area parameterizations
We investigate the solvent-accessible area method by means of Metropolis
simulations of the brain peptide Met-Enkephalin at 300. For the energy
function ECEPP/2 nine atomic solvation parameter (ASP) sets are studied. The
simulations are compared with one another, with simulations with a distance
dependent electrostatic permittivity , and with vacuum
simulations (). Parallel tempering and the biased Metropolis
techniques RM are employed and their performance is evaluated. The measured
observables include energy and dihedral probability densities (pds), integrated
autocorrelation times, and acceptance rates. Two of the ASP sets turn out to be
unsuitable for these simulations. For all other systems selected configurations
are minimized in search of the global energy minima, which are found for the
vacuum and the system, but for none of the ASP models. Other
observables show a remarkable dependence on the ASPs. In particular, we find
three ASP sets for which the autocorrelations at 300K are considerably
smaller than for vacuum simulations.Comment: 10 pages and 8 figure
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