Study of High-Transverse-Momentum Higgs Boson Production in Association with a Vector Boson in the qqbb Final State with the ATLAS Detector

This Letter presents the first study of Higgs boson production in association with a vector boson (V=W or Z) in the fully hadronic qqbb final state using data recorded by the ATLAS detector at the LHC in proton-proton collisions at sqrt[s]=13  TeV and corresponding to an integrated luminosity of 137  fb^{-1}. The vector bosons and Higgs bosons are each reconstructed as large-radius jets and tagged using jet substructure techniques. Dedicated tagging algorithms exploiting b-tagging properties are used to identify jets consistent with Higgs bosons decaying into bb[over ¯]. Dominant backgrounds from multijet production are determined directly from the data, and a likelihood fit to the jet mass distribution of Higgs boson candidates is used to extract the number of signal events. The VH production cross section is measured inclusively and differentially in several ranges of Higgs boson transverse momentum: 250-450, 450-650, and greater than 650 GeV. The inclusive signal yield relative to the standard model expectation is observed to be μ=1.4_{-0.9}^{+1.0} and the corresponding cross section is 3.1±1.3(stat)_{-1.4}^{+1.8}(syst)  pb.

Measurement of the Centrality Dependence of the Dijet Yield in p+Pb Collisions at sqrt[s_{NN}]=8.16 TeV with the ATLAS Detector

ATLAS measured the centrality dependence of the dijet yield using 165  nb^{-1} of p+Pb data collected at sqrt[s_{NN}]=8.16  TeV in 2016. The event centrality, which reflects the p+Pb impact parameter, is characterized by the total transverse energy registered in the Pb-going side of the forward calorimeter. The central-to-peripheral ratio of the scaled dijet yields, R_{CP}, is evaluated, and the results are presented as a function of variables that reflect the kinematics of the initial hard parton scattering process. The R_{CP} shows a scaling with the Bjorken x of the parton originating from the proton, x_{p}, while no such trend is observed as a function of x_{Pb}. This analysis provides unique input to understanding the role of small proton spatial configurations in p+Pb collisions by covering parton momentum fractions from the valence region down to x_{p}∼10^{-3} and x_{Pb}∼4×10^{-4}.

Search for New Phenomena in Two-Body Invariant Mass Distributions Using Unsupervised Machine Learning for Anomaly Detection at sqrt[s]=13 TeV with the ATLAS Detector

Searches for new resonances are performed using an unsupervised anomaly-detection technique. Events with at least one electron or muon are selected from 140  fb^{-1} of pp collisions at sqrt[s]=13  TeV recorded by ATLAS at the Large Hadron Collider. The approach involves training an autoencoder on data, and subsequently defining anomalous regions based on the reconstruction loss of the decoder. Studies focus on nine invariant mass spectra that contain pairs of objects consisting of one light jet or b jet and either one lepton (e,μ), photon, or second light jet or b jet in the anomalous regions. No significant deviations from the background hypotheses are observed. Limits on contributions from generic Gaussian signals with various widths of the resonance mass are obtained for nine invariant masses in the anomalous regions.

Observation of WZγ Production in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector

This Letter reports the observation of WZγ production and a measurement of its cross section using 140.1±1.2  fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. The WZγ production cross section, with both the W and Z bosons decaying leptonically, pp→WZγ→ℓ^{'}^{±}νℓ^{+}ℓ^{-}γ (ℓ^{(^{'})}=e, μ), is measured in a fiducial phase-space region defined such that the leptons and the photon have high transverse momentum and the photon is isolated. The cross section is found to be 2.01±0.30(stat)±0.16(syst)  fb. The corresponding standard model predicted cross section calculated at next-to-leading order in perturbative quantum chromodynamics and at leading order in the electroweak coupling constant is 1.50±0.06  fb. The observed significance of the WZγ signal is 6.3σ, compared with an expected significance of 5.0σ.

Combined Measurement of the Higgs Boson Mass from the H→γγ and H→ZZ^{*}→4ℓ Decay Channels with the ATLAS Detector Using sqrt[s]=7, 8, and 13 TeV pp Collision Data

A measurement of the mass of the Higgs boson combining the H→ZZ^{*}→4ℓ and H→γγ decay channels is presented. The result is based on 140  fb^{-1} of proton-proton collision data collected by the ATLAS detector during LHC run 2 at a center-of-mass energy of 13 TeV combined with the run 1 ATLAS mass measurement, performed at center-of-mass energies of 7 and 8 TeV, yielding a Higgs boson mass of 125.11±0.09(stat)±0.06(syst)=125.11±0.11  GeV. This corresponds to a 0.09% precision achieved on this fundamental parameter of the Standard Model of particle physics.

Search for Dark Photons in Rare Z Boson Decays with the ATLAS Detector

A search for events with a dark photon produced in association with a dark Higgs boson via rare decays of the standard model Z boson is presented, using 139  fb^{-1} of sqrt[s]=13  TeV proton-proton collision data recorded by the ATLAS detector at the Large Hadron Collider. The dark boson decays into a pair of dark photons, and at least two of the three dark photons must each decay into a pair of electrons or muons, resulting in at least two same-flavor opposite-charge lepton pairs in the final state. The data are found to be consistent with the background prediction, and upper limits are set on the dark photon's coupling to the dark Higgs boson times the kinetic mixing between the standard model photon and the dark photon, α_{D}ϵ^{2}, in the dark photon mass range of [5, 40] GeV except for the ϒ mass window [8.8, 11.1] GeV. This search explores new parameter space not previously excluded by other experiments.

Observation of Single-Top-Quark Production in Association with a Photon Using the ATLAS Detector

This Letter reports the observation of single top quarks produced together with a photon, which directly probes the electroweak coupling of the top quark. The analysis uses 139  fb^{-1} of 13 TeV proton-proton collision data collected with the ATLAS detector at the Large Hadron Collider. Requiring a photon with transverse momentum larger than 20 GeV and within the detector acceptance, the fiducial cross section is measured to be 688±23(stat) _{-71}^{+75}(syst)  fb, to be compared with the standard model prediction of 515_{-42}^{+36}  fb at next-to-leading order in QCD.

Measurement of Suppression of Large-Radius Jets and Its Dependence on Substructure in Pb+Pb Collisions at sqrt[s_{NN}]=5.02 TeV with the ATLAS Detector

This letter presents a measurement of the nuclear modification factor of large-radius jets in sqrt[s_{NN}]=5.02  TeV Pb+Pb collisions by the ATLAS experiment. The measurement is performed using 1.72  nb^{-1} and 257  pb^{-1} of Pb+Pb and pp data, respectively. The large-radius jets are reconstructed with the anti-k_{t} algorithm using a radius parameter of R=1.0, by reclustering anti-k_{t} R=0.2 jets, and are measured over the transverse momentum (p_{T}) kinematic range of 158 Collapse

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Measurement of the Sensitivity of Two-Particle Correlations in pp Collisions to the Presence of Hard Scatterings

A key open question in the study of multiparticle production in high-energy pp collisions is the relationship between the "ridge"-i.e., the observed azimuthal correlations between particles in the underlying event that extend over all rapidities-and hard or semihard scattering processes. In particular, it is not known whether jets or their soft fragments are correlated with particles in the underlying event. To address this question, two-particle correlations are measured in pp collisions at sqrt[s]=13  TeV using data collected by the ATLAS experiment at the LHC, with an integrated luminosity of 15.8  pb^{-1}, in two different configurations. In the first case, charged particles associated with jets are excluded from the correlation analysis, while in the second case, correlations are measured between particles within jets and charged particles from the underlying event. Second-order flow coefficients, v_{2}, are presented as a function of event multiplicity and transverse momentum. These measurements show that excluding particles associated with jets does not affect the measured correlations. Moreover, particles associated with jets do not exhibit any significant azimuthal correlations with the underlying event, ruling out hard processes contributing to the ridge.

Observation of an Excess of Dicharmonium Events in the Four-Muon Final State with the ATLAS Detector

A search is made for potential ccc[over ¯]c[over ¯] tetraquarks decaying into a pair of charmonium states in the four muon final state using proton-proton collision data at sqrt[s]=13  TeV, corresponding to an integrated luminosity of 140  fb^{-1} recorded by the ATLAS experiment at LHC. Two decay channels, J/ψ+J/ψ→4μ and J/ψ+ψ(2S)→4μ, are studied. Backgrounds are estimated based on a hybrid approach involving Monte Carlo simulations and data-driven methods. Statistically significant excesses with respect to backgrounds dominated by the single parton scattering are seen in the di-J/ψ channel consistent with a narrow resonance at 6.9 GeV and a broader structure at lower mass. A statistically significant excess is also seen in the J/ψ+ψ(2S) channel. The fitted masses and decay widths of the structures are reported.

Observation of the γγ→ττ Process in Pb+Pb Collisions and Constraints on the τ-Lepton Anomalous Magnetic Moment with the ATLAS Detector

This Letter reports the observation of τ-lepton-pair production in ultraperipheral lead-lead collisions Pb+Pb→Pb(γγ→ττ)Pb and constraints on the τ-lepton anomalous magnetic moment a_{τ}. The dataset corresponds to an integrated luminosity of 1.44  nb^{-1} of LHC Pb+Pb collisions at sqrt[s_{NN}]=5.02  TeV recorded by the ATLAS experiment in 2018. Selected events contain one muon from a τ-lepton decay, an electron or charged-particle track(s) from the other τ-lepton decay, little additional central-detector activity, and no forward neutrons. The γγ→ττ process is observed in Pb+Pb collisions with a significance exceeding 5 standard deviations and a signal strength of μ_{ττ}=1.03_{-0.05}^{+0.06} assuming the standard model value for a_{τ}. To measure a_{τ}, a template fit to the muon transverse-momentum distribution from τ-lepton candidates is performed, using a dimuon (γγ→μμ) control sample to constrain systematic uncertainties. The observed 95% confidence-level interval for a_{τ} is -0.057 Collapse

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Efficacy of immune checkpoint inhibitors for the treatment of advanced melanoma in patients with concomitant chronic lymphocytic leukemia

BACKGROUND

Immune checkpoint inhibitors (ICIs) have revolutionized the management of advanced melanoma (AM). However, data on ICI effectiveness have largely been restricted to clinical trials, thereby excluding patients with co-existing malignancies. Chronic lymphocytic leukemia (CLL) is the most prevalent adult leukemia and is associated with increased risk of melanoma. CLL alters systemic immunity and can induce T-cell exhaustion, which may limit the efficacy of ICIs in patients with CLL. We, therefore, sought to examine the efficacy of ICI in patients with these co-occurring diagnoses.

PATIENTS AND METHODS

In this international multicenter study, a retrospective review of clinical databases identified patients with concomitant diagnoses of CLL and AM treated with ICI (US-MD Anderson Cancer Center, N = 24; US-Mayo Clinic, N = 15; AUS, N = 19). Objective response rates (ORRs), assessed by RECIST v1.1, and survival outcomes [overall survival (OS) and progression-free survival (PFS)] among patients with CLL and AM were assessed. Clinical factors associated with improved ORR and survival were explored. Additionally, ORR and survival outcomes were compared between the Australian CLL/AM cohort and a control cohort of 148 Australian patients with AM alone.

RESULTS

Between 1997 and 2020, 58 patients with concomitant CLL and AM were treated with ICI. ORRs were comparable between AUS-CLL/AM and AM control cohorts (53% versus 48%, P = 0.81). PFS and OS from ICI initiation were also comparable between cohorts. Among CLL/AM patients, a majority were untreated for their CLL (64%) at the time of ICI. Patients with prior history of chemoimmunotherapy treatment for CLL (19%) had significantly reduced ORRs, PFS, and OS.

CONCLUSIONS

Our case series of patients with concomitant CLL and melanoma demonstrate frequent, durable clinical responses to ICI. However, those with prior chemoimmunotherapy treatment for CLL had significantly worse outcomes. We found that CLL disease course is largely unchanged by treatment with ICI.

Strong Constraints on Jet Quenching in Centrality-Dependent p+Pb Collisions at 5.02 TeV from ATLAS

Jet quenching is the process of color-charged partons losing energy via interactions with quark-gluon plasma droplets created in heavy-ion collisions. The collective expansion of such droplets is well described by viscous hydrodynamics. Similar evidence of collectivity is consistently observed in smaller collision systems, including pp and p+Pb collisions. In contrast, while jet quenching is observed in Pb+Pb collisions, no evidence has been found in these small systems to date, raising fundamental questions about the nature of the system created in these collisions. The ATLAS experiment at the Large Hadron Collider has measured the yield of charged hadrons correlated with reconstructed jets in 0.36  nb^{-1} of p+Pb and 3.6  pb^{-1} of pp collisions at 5.02 TeV. The yields of charged hadrons with p_{T}^{ch}>0.5  GeV near and opposite in azimuth to jets with p_{T}^{jet}>30 or 60 GeV, and the ratios of these yields between p+Pb and pp collisions, I_{pPb}, are reported. The collision centrality of p+Pb events is categorized by the energy deposited by forward neutrons from the struck nucleus. The I_{pPb} values are consistent with unity within a few percent for hadrons with p_{T}^{ch}>4  GeV at all centralities. These data provide new, strong constraints that preclude almost any parton energy loss in central p+Pb collisions.

Test of CP Invariance in Higgs Boson Vector-Boson-Fusion Production Using the H→γγ Channel with the ATLAS Detector

A test of CP invariance in Higgs boson production via vector-boson fusion has been performed in the H→γγ channel using 139  fb^{-1} of proton-proton collision data at sqrt[s]=13  TeV collected by the ATLAS detector at the LHC. The optimal observable method is used to probe the CP structure of interactions between the Higgs boson and electroweak gauge bosons, as described by an effective field theory. No sign of CP violation is observed in the data. Constraints are set on the parameters describing the strength of the CP-odd component in the coupling between the Higgs boson and the electroweak gauge bosons in two effective field theory bases: d[over ˜] in the HISZ basis and c_{HW[over ˜]} in the Warsaw basis. The results presented are the most stringent constraints on CP violation in the coupling between Higgs and weak bosons. The 95% C.L. constraint on d[over ˜] is derived for the first time and the 95% C.L. constraint on c_{HW[over ˜]} has been improved by a factor of 5 compared to the previous measurement.

Mortality and histopathology in sheepshead minnow (Cyprinodon variegatus) larvae exposed to pectenotoxin-2 and Dinophysis acuminata

Toxic species of the dinoflagellate genus Dinophysis can produce diarrheic toxins including okadaic acid (OA) and dinophysistoxins (DTXs), and the non-diarrheic pectenotoxins (PTXs). Okadaic acid and DTXs cause diarrheic shellfish poisoning (DSP) in human consumers, and also cause cytotoxic, immunotoxic and genotoxic effects in a variety of mollusks and fishes at different life stages in vitro. The possible effects of co-produced PTXs or live cells of Dinophysis to aquatic organisms, however, are less understood. Effects on an early life stage of sheepshead minnow (Cyprinodon variegatus), a common finfish in eastern USA estuaries, were evaluated using a 96-h toxicity bioassay. Three-week old larvae were exposed to PTX2 concentrations from 50 to 4000 nM, live Dinophysis acuminata culture (strain DAVA01), live cells resuspended in clean medium or culture filtrate. This D. acuminata strain produced mainly intracellular PTX2 (≈ 21 pg cell^-1), with much lower levels of OA and dinophysistoxin-1. No mortality or gill damages were observed in larvae exposed to D. acuminata (from 5 to 5500 cells mL^-1), resuspended cells and culture filtrate. However, exposure to purified PTX2 at intermediate to high concentrations (from 250 to 4000 nM) resulted in 8 to 100% mortality after 96 h (24-h LC₅₀ of 1231 nM). Histopathology and transmission electron microscopy of fish exposed to intermediate to high PTX2 concentrations revealed important gill damage, including intercellular edema, necrosis and sloughing of gill respiratory epithelia, and damage to the osmoregulatory epithelium, including hypertrophy, proliferation, redistribution and necrosis of chloride cells. Tissue damage in gills is likely caused by the interaction of PTX2 with the actin cytoskeleton of the affected gill epithelia. Overall, the severe gill pathology observed following the PTX2 exposure suggested death was due to loss of respiratory and osmoregulatory functions in C. variegatus larvae.

Targeting improved resilience in Merino sheep - Correlations between immune competence and health and fitness traits

Resilience can be defined as the ability of an animal to remain productive in the face of diverse environmental challenges. Several factors contribute to an animal's resilience including its ability to resist disease, cope with climatic extremes and respond to stressors. Immune competence, a proxy trait for general disease resistance, is expected to contribute to an animal's resilience. This research aimed to develop a practical method to assess immune competence in Merino sheep which would not restrict the future sale of tested animals, and to estimate genetic parameters associated with the novel trait. We also aimed to explore associations between immune competence and other industry-relevant disease resistance and fitness-related traits and to assess the ability of immune competence phenotypes to predict health outcomes. Here, the ability of Merino wethers (n = 1 339) to mount both an antibody-mediated and cell-mediated immune response was used to define their immune competence phenotype. For that purpose, antigens in a commercial vaccine were administered at the commencement of weaning and their responses were assessed. Univariate sire models were used to estimate variance components and heritabilities for immune competence and its component traits. Bivariate sire models were used to estimate genetic correlations between immune competence and a range of disease resistance and fitness-related traits. The heritability of immune competence and its component traits, antibody-mediated immune response and cell-mediated immune response were estimated at 0.49 ± 0.14, 0.52 ± 0.14 and 0.36 ± 0.11, respectively. Immune competence was favourably genetically correlated with breech flystrike incidence (-0.44 ± 0.39), worm egg count (-0.19 ± 0.23), dag score (-0.26 ± 0.31) and fitness compromise (-0.35 ± 0.24) but not fleece rot (0.17 ± 0.23). Results suggest that selection for immune competence has the potential to improve the resilience of Merino sheep; however, due to the large standard errors associated with correlation estimates reported here, further studies will be required in larger populations to validate associations between immune competence and disease resistance and fitness traits in Australian Merino sheep.

Robust bulk micro-nano hierarchical copper structures possessing exceptional bactericidal efficacy

Conventional copper (Cu) metal surfaces are well recognized for their bactericidal properties. However, their slow bacteria-killing potency has historically excluded them as a rapid bactericidal material. We report the development of a robust bulk superhydrophilic micro-nano hierarchical Cu structure that possesses exceptional bactericidal efficacy. It resulted in a 4.41 log₁₀ reduction (>99.99%) of the deadly Staphylococcus aureus (S. aureus) bacteria within 2 min vs. a 1.49 log₁₀ reduction (96.75%) after 240 min on common Cu surfaces. The adhered cells exhibited extensive blebbing, loss of structural integrity and leakage of vital intracellular material, demonstrating the rapid efficacy of the micro-nano Cu structure in destructing bacteria membrane integrity. The mechanism was attributed to the synergistic degradation of the cell envelope through enhanced release and therefore uptake of the cytotoxic Cu ions and the adhesion-driven mechanical strain due to its rapid ultimate superhydrophilicity (contact angle drops to 0° in 0.18 s). The scalable fabrication of this micro-nano Cu structure was enabled by integrating bespoke precursor alloy design with microstructure preconditioning for dealloying and demonstrated on 2000 mm² Cu surfaces. This development paves the way to the practical exploitation of Cu as a low-cost antibiotic-free fast bactericidal material.

'Stat' workflow modifications to expedite care after needlestick injuries

BACKGROUND

Post-exposure prophylaxis (PEP) for human immunodeficiency virus (HIV) is recommended to start within hours of needlestick injuries (NSIs) among healthcare workers (HCWs). Delays associated with awaiting the results of testing from the source patient (whose blood was involved in the NSI) can lead to psychological consequences for the exposed HCW as well as symptomatic toxicities from empiric PEP.

AIMS

After developing a 'stat' (immediate) workflow that prioritized phlebotomy and resulting of source patient bloodwork for immediate handling and processing, we retrospectively investigated whether our new workflow had (i) decreased HIV order-result interval times for source patient HIV bloodwork and (ii) decreased the frequency of HIV PEP prescriptions being dispensed to exposed HCWs.

METHODS

We retrospectively analysed NSI records to identify source patient HIV order-result intervals and PEP dispensing frequencies across a 6-year period (encompassing a 54-month pre-intervention period and 16-month post-intervention period).

RESULTS

We identified 251 NSIs, which occurred at similar frequencies before versus after our intervention (means 3.54 NSIs and 3.75 NSIs per month, respectively). Median HIV order-result intervals decreased significantly (P < 0.05) from 195 to 156 min after our intervention, while the proportion of HCWs who received one or more doses of PEP decreased significantly (P < 0.001) from 50% (96/191) to 23% (14/60).

CONCLUSION

Using a 'stat' workflow to prioritize source patient testing after NSIs, we achieved a modest decrease in order-result intervals and a dramatic decrease in HIV PEP dispensing rates. This simple intervention may improve HCWs' physical and psychological health during a traumatic time.

Altered Processing of Complex Visual Stimuli in Patients with Postconcussive Visual Motion Sensitivity

BACKGROUND AND PURPOSE

Vestibular symptoms are common after concussion. Vestibular Ocular Motor Screening identifies vestibular impairment, including postconcussive visual motion sensitivity, though the underlying functional brain alterations are not defined. We hypothesized that alterations in multisensory processing are responsible for postconcussive visual motion sensitivity, are detectable on fMRI, and correlate with symptom severity.

MATERIALS AND METHODS

Twelve patients with subacute postconcussive visual motion sensitivity and 10 healthy control subjects underwent vestibular testing and a novel fMRI visual-vestibular paradigm including 30-second "neutral" or "provocative" videos. The presence of symptoms/intensity was rated immediately after each video. fMRI group-level analysis was performed for a "provocative-neutral" condition. Z-statistic images were nonparametrically thresholded using clusters determined by Z > 2.3 and a corrected cluster significance threshold of P = .05. Symptoms assessed on Vestibular Ocular Motor Screening were correlated with fMRI mean parameter estimates using Pearson correlation coefficients.

RESULTS

Subjects with postconcussive visual motion sensitivity had significantly more Vestibular Ocular Motor Screening abnormalities and increased symptoms while viewing provocative videos. While robust mean activation in the primary and secondary visual areas, the parietal lobe, parietoinsular vestibular cortex, and cingulate gyrus was seen in both groups, selective increased activation was seen in subjects with postconcussive visual motion sensitivity in the primary vestibular/adjacent cortex and inferior frontal gyrus, which are putative multisensory visual-vestibular processing centers. Moderate-to-strong correlations were found between Vestibular Ocular Motor Screening scores and fMRI activation in the left frontal eye field, left middle temporal visual area, and right posterior hippocampus.

CONCLUSIONS

Increased fMRI brain activation in visual-vestibular multisensory processing regions is selectively seen in patients with postconcussive visual motion sensitivity and is correlated with Vestibular Ocular Motor Screening symptom severity, suggesting that increased visual input weighting into the vestibular network may underlie postconcussive visual motion sensitivity.

Sweet Corn Sentinel Monitoring for Lepidopteran Field-Evolved Resistance to Bt Toxins

As part of an insect resistance management plan to preserve Bt transgenic technology, annual monitoring of target pests is mandated to detect susceptibility changes to Bt toxins. Currently Helicoverpa zea (Boddie) monitoring involves investigating unexpected injury in Bt crop fields and collecting larvae from non-Bt host plants for laboratory diet bioassays to determine mortality responses to diagnostic concentrations of Bt toxins. To date, this monitoring approach has not detected any significant change from the known range of baseline susceptibility to Bt toxins, yet practical field-evolved resistance in H. zea populations and numerous occurrences of unexpected injury occur in Bt crops. In this study, we implemented a network of 73 sentinel sweet corn trials, spanning 16 U.S. states and 4 Canadian provinces, for monitoring changes in H. zea susceptibility to Cry and Vip3A toxins by measuring differences in ear damage and larval infestations between isogenic pairs of non-Bt and Bt hybrids over three years. This approach can monitor susceptibility changes and regional differences in other ear-feeding lepidopteran pests. Temporal changes in the field efficacy of each toxin were evidenced by comparing our current results with earlier published studies, including baseline data for each Bt trait when first commercialized. Changes in amount of ear damage showed significant increases in H. zea resistance to Cry toxins and possibly lower susceptibility to Vip3a. Our findings demonstrate that the sentinel plot approach as an in-field screen can effectively monitor phenotypic resistance and document field-evolved resistance in target pest populations, improving resistance monitoring for Bt crops.

The α2,3-selective potentiators of GABAA receptors, KRM-II-81 and MP-III-80, produce anxiolytic-like effects and block chemotherapy-induced hyperalgesia in mice without tolerance development

Opiate analgesics are one of the treatment options for severe chronic pain, including late-stage cancer, chronic back pain and other disorders. The recent resurgence in opioid overdose has highlighted the serious need for alternative medicines for pain management. While a role for potentiators of α2/3-containing GABA_A receptors in the modulation of pain has been known for several years, advancements in this area required data from selective compounds. KRM-II-81(5-(8-ethynyl-6-(pyridin-2-yl)-4H-benzo[f]imidazo[1,5-a][1,4]diazepin-3- yl)oxazole) and analogs selectively potentiate GABA_A receptors containing α2/3 subunits and have recently been shown to attenuate pain behaviors in several acute and chronic pain models in rodents. The present study was designed to ascertain whether KRM-II-81 and the structural analog MP-III-80 (3-ethyl-5-(8-ethynyl-6-(pyridin-2-yl)-4H-benzo[f]imidazo[1,5-a][1,4]diazepin-3-yl)-1,2,4-oxadiazole) would block chemotherapeutic agent paclitaxel-induced pain in male, C57BL/6 mice. Both compounds significantly inhibited pain behaviors evoked by cold and tactile stimulation in paclitaxel-treated mice as did the neuropathic pain drug gabapentin. Subchronic dosing for 22 days with KRM-II-81 and MP-III-80 demonstrated enduring analgesic efficacy without tolerance development, while the effects of gabapentin showed evidence of tolerance development. KRM-II-81 and MP-III-80 also decreased marble-burying behavior in this mouse strain as did the anxiolytic drug chlordiazepoxide. In contrast to KRM-II-81 and MP-III-80, chlordiazepoxide had motor-impairing effects at anxiolytic-like doses. The data add to the literature documenting that these selective potentiators of α2/3-containing GABA_A receptors are effective in a host of animal models used to detect novel analgesic drugs. The anxiolytic-like efficacy of these compounds fits well with the comorbidity of anxiety in patients with chronic pain and cancer.

R-(-)-ketamine modifies behavioral effects of morphine predicting efficacy as a novel therapy for opioid use disorder1

Substance abuse disorder continues to have devastating consequences for individuals and society and current therapies are not sufficient to provide the magnitude of medical impact required. Although some evidence suggests the use of ketamine in treating various substance use related- symptoms, its adverse event profile including dissociation, dysphoria, and abuse liability limit its potential as a therapy. Here, we outline experiments to test our hypothesis that (R)-ketamine can both alleviate withdrawal symptoms and produce effects that help sustain abstinence. In morphine-dependent rats, (R)-ketamine alleviated naloxone-precipitated withdrawal signs. (R)-ketamine also blocked morphine-induced place preference in mice without inducing place preference on its own. We also evaluated whether (R)-ketamine would induce anhedonia, a counter-indicated effect for a drug abuse treatment agent. S-(+)- but not R-(-)-ketamine produced anhedonia-like responses in rats that electrically self-stimulated the medial forebrain bundle (ICSS). However, time-course studies of ICSS are needed to fully appreciate these differences. These data begin to support the claim that (R)-ketamine will dampen withdrawal symptoms and drug liking, factors known to contribute to the cycle of drug addiction. In addition, these data suggest that (R)-ketamine would not produce negative mood or anhedonia that could interfere with treatment. It is suggested that continued investigation of (R)-ketamine as a novel therapeutic for substance abuse disorder be given consideration by the preclinical and clinical research communities. This suggestion is further encouraged by a recent report on the efficacy of (R)-ketamine in treatment-resistant depressed patients at a dose with little measurable dissociative side-effects.

The α2,3-selective potentiator of GABAA receptors, KRM-II-81, reduces nociceptive-associated behaviors induced by formalin and spinal nerve ligation in rats

Clinical evidence indicates that positive allosteric modulators (PAMs) of GABAA receptors have analgesic benefit in addition to efficacy in anxiety disorders. However, the utility of GABAA receptor PAMs as analgesics is compromised by the central nervous system side effects of non-selective potentiators. A selective potentiator of GABAA receptors associated with α2/3 subunits, KRM-II-81(5-(8-ethynyl-6-(pyridin-2-yl)-4H-benzo[f]imidazo[1,5-a][1,4]diazepin-3-yl)oxazole), has demonstrated anxiolytic, anticonvulsant, and antinociceptive effects in rodents with reduced motoric side effects. The present study evaluated the potential of KRM-II-81 as a novel analgesic. Oral administration of KRM-II-81 attenuated formalin-induced flinching; in contrast, diazepam was not active. KRM-II-81 attenuated nociceptive-associated behaviors engendered by chronic spinal nerve ligation (L5/L6). Diazepam decreased locomotion of rats at the dose tested in the formalin assay (10 mg/kg) whereas KRM-II-81 produced small decreases that were not dose-dependent (10-100 mg/kg). Plasma and brain levels of KRM-II-81 were used to demonstrate selectivity for α2/3- over α1-associated GABAA receptors and to define the degree of engagement of these receptors. Plasma and brain concentrations of KRM-II-81 were positively-associated with analgesic efficacy. GABA currents from isolated rat dorsal-root ganglion cultures were potentiated by KRM-II-81 with an ED50 of 32 nM. Measures of respiratory depression were reduced by alprazolam whereas KRM-II-81 was either inactive or produced effects with lower potency and efficacy. These findings add to the growing body of data supporting the idea that α2/3-selective GABAA receptor PAMs will have efficacy and tolerability as pain medications including those for neuropathic pain. Given their predicted anxiolytic effects, α2/3-selective GABAA receptor PAMs offer an additional inroad into the management of pain.

Leptospirosis: An important infectious disease in North American horses

North American horses are commonly exposed to Leptospira organisms. Leptospira Bratislava is the most common infecting serovar but this serovar has not been confirmed to cause clinical disease in North American horses. Leptospira Pomona type kennewicki is responsible for most of the clinical diseases (leptospirosis) in North American horses. Leptospirosis is most commonly associated with diseases of the placenta and fetus, the kidneys and the eyes in horses. In-utero infections in pregnant mares may result in abortion, neonatal illness or birth of an antibody positive healthy foal. Acute renal failure in younger horses and recurrent uveitis in adult horses are other well documented clinical syndromes of leptospirosis. Abortions, neonatal disease and acute renal failure are caused by a subacute infection, while horses with Leptospira associated recurrent uveitis develop ocular disease months or years after the initial Leptospira infection. Diagnosis of Leptospirosis is made by a combination of antigen or antibody testing methods. Mares that abort following Leptospira infection have no additional clinical signs at the time of abortion but may shed the offending Leptospira spp. in the urine for several weeks. Antibiotic treatments are sometimes used in hopes of decreasing Leptospira shedding in infected horses or prophylactically in exposed pregnant mares but documentation of efficacy is lacking. Horses with Leptospira - associated acute renal failure can be successfully treated with antibiotics and supportive care. Recurrent uveitis is commonly associated with leptospirosis in North American horses and although horses may have chronic intraocular infection triggering an immune disease, systemic antimicrobial therapy has not been effective in eliminating the organism from the eye. An equine approved Leptospira Pomona type kennewicki vaccine is now available in North America.

Establishment of Striacosta albicosta (Lepidoptera: Noctuidae) as a Primary Pest of Corn in the Great Lakes Region

Western bean cutworm, Striacosta albicosta Smith (Lepidoptera: Noctuidae), is a pest of corn, Zea maize L., and dry edible beans, Phaseolus sp. L., native to the western United States. Following the range expansion into the U.S. Corn Belt, pheromone trap monitoring began in the Great Lakes region in 2006. The first S. albicosta was captured in Michigan in 2006 and in Ontario, Canada in 2008. Pheromone traps were used to document spread and increasing captures of S. albicosta across Michigan and Ontario until 2012. Trapping confirmed the univoltine life cycle of S. albicosta in this region and identified peak flight, typically occurring in late July. Overwintering of S. albicosta in this region was confirmed by emergence from infested fields and overwintering experiments. Multiple soil textures were infested with prepupae, and recovery was assessed throughout the winter. Overwintering success was not affected by soil texture; however, prepupae were found at greater depths in coarse-textured soils. Soil temperatures at overwintering depths did not reach the supercooling point. Injury to corn by S. albicosta increased in incidence, severity and geographic range from 2010 to 2014 in field plots. Decreasing control of injury by Cry1F corn hybrids was observed over time. These findings show that S. albicosta has established as a perennial corn pest in the Great Lakes region due to observations of overwintering success and unmanaged injury. We recommend S. albicosta obtain primary pest status in this region within regulatory framework and a resistance management plan be required for traits targeting this pest.

Assessment of the relationship between a written measure of empathy and an independently rated interview of Motivational Interviewing

Motivational Interviewing (MI) is an evidence-based practice shown to be effective when working with people in treatment for substance use disorders. However, MI is a complex treatment modality optimized by training with feedback. Feedback, assessment and monitoring of treatment fidelity require measurement, which is typically done using audiotaped sessions. The gold standard for such measurement of MI skill has been an audiotaped interview, scored by a rater with a detailed structured instrument such as the Motivational Interviewing Treatment Integrity 2.0 (MITI 2.0) Coding System (Moyers, et al., 2005). The Helpful Responses Questionnaire (HRQ) (Miller, Hedrick, & Orlofsky, 1991) is a pen-and-paper test of empathy (a foundational MI skill) that does not require an audiotaped session. A randomized trial of three different regimens for training counselors in MI (live supervision using Teleconferencing, Tape-based supervision and Workshop only) (Smith et al., 2012) offered the opportunity to evaluate the performance of the HRQ as a measure of MI ability, compared to the several MITI 2.0 global scores and subscales. Participants were counselors (N=97) working at community-based substance use treatment programs, whose MI proficiency was measured at four time points: baseline (before an initial 2-day MI workshop), post-workshop, 8weeks post-workshop (i.e., post-supervision), and 20weeks post-workshop with both MITI 2.0 and HRQ. HRQ total scores correlated significantly with the Reflection to Question Ratio from the MITI 2.0 at post-workshop (r=0.33), week 8 (r=0.34), and week 20 (r=0.38), and with the Spirit (r=0.32) and Empathy (r=0.32) global scores at week 20. Correlations of HRQ with other MITI 2.0 subscales and time points after workshop were small and not significant. As predicted, HRQ scores differed between training conditions (X²(2)=7.88, p=0.02), with counselors assigned to live supervision achieving better HRQ scores than those in Workshop only. In summary, HRQ is a modestly accurate measure, mainly of the Reflection to Question Ratio, considered a core marker of MI skill. It is sensitive to training effects and may help identify counselors needing more intensive supervision. Given its ease of administration and scoring, HRQ may be a useful marker of MI skill during training efforts.

Abstract P3-05-01: Immune and transcriptional signatures of dendritic dell (DC) vaccination combined with chemotherapy in locally advanced, triple-negative breast cancer (TNBC) patients

BACKGROUND: Women with TNBC who do not achieve a pathologic complete response (pCR) with preoperative (preop) chemotherapy have a high risk of recurrence and death from BC. Immunotherapy is an attractive strategy as human BCs can be immunogenic, and enhancing the immune effector function may augment the cytotoxic effects of standard therapies.

CLINICAL TRIAL: Following IRB-approved informed consent, 10 pts with locally advanced TNBC received preop dose-dense doxorubicin/cyclophosphamide (AC) followed by paclitaxel and carboplatin (TCb) chemotherapy, combined with antigen-loaded (TNBC antigens: Cyclin B1, WT1, and control viral antigens: CEF) autologous monocyte-derived DC vaccinations administered intratumorally and subcutaneously. DCs were generated with GM-CSF and type I interferon, loaded with antigen in the form of long peptides and activated with innate ligands (LPS and Clo75) and CD40 ligand. Vaccines were given at 4 time points prior to definitive surgery, and 3 times post-surgery, pre- and post-radiation therapy (RT). Safety was the primary study endpoint, and pCR rate in breast and axilla was a secondary endpoint. Correlative studies included assessment of immune response via ELISpot and transcriptional profiling of blood samples collected over time.

RESULTS: All pts received the 4 vaccines during preop chemotherapy, and 7/10 received all 7 vaccines. At the time of definitive surgery, 4 pts achieved a pCR, 3 pts had macroscopic residual disease in the breast and axillary lymph nodes, and 3 pts had residual cancer burden scores of 1. As of June 1, 2017, all pts have been in follow-up for at least 1 year s/p completion of all vaccines, and 7/10 patients have no evidence of disease.

To assess immune signatures with IFN-γ-ELISpot, PBMCs from baseline (BL) and several time points during vaccine treatment were cultured with control peptides or with peptide libraries covering vaccine antigens. Using a linear mixed model to account for repeated and missing observations we found statistically significant (α = 0.05) increases in Cyclin B1, WT1, and CEF ELISpots in at least 1 time point post-DC vaccination and in follow-up. Compared to BL, Cyclin B1 and WT1 increased at 3 day pre-RT in 8/10 and 7/10 pts, respectively. To assess transcriptional signatures, a linear mixed model was utilized to determine statistically significant differences in fold-change over time compared to the BL and healthy controls. Modular analysis of differentially expressed transcripts at BL revealed downregulation of transcripts related to the monocyte lineage in 7/10 pts. Longitudinal analysis revealed profound transcriptional changes during AC with downregulation of lymphocyte modules and upregulation of innate and inflammation modules. While the latter ones have normalized during TCb and follow-up, T cell module remained substantially downregulated throughout treatment and follow-up.

CONCLUSIONS: Combination of preop chemotherapy and intratumoral and subcutaneous autologous DC vaccination is safe in locally advanced TNBC pts and is linked with profound changes in immune transcription signatures and with expansion of antigen-specific immune responses that can be detected in IFN-γ ELISpot.

Citation Format: Palucka AK, Roberts LK, Zurawski SM, Tarnowski J, Turner J, Wang X, Blankenship D, Smith JL, Levin MK, Finholt JP, Burkeholder SB, Timis R, Muniz LS, Dao T, Grant M, Banchereau J, Zurawski G, Pascual V, O'Shaughnessy JA. Immune and transcriptional signatures of dendritic dell (DC) vaccination combined with chemotherapy in locally advanced, triple-negative breast cancer (TNBC) patients [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-05-01.

Evidence for Field-Evolved Resistance of Striacosta albicosta (Lepidoptera: Noctuidae) to Cry1F Bacillus thuringiensis Protein and Transgenic Corn Hybrids in Ontario, Canada

Western bean cutworm, Striacosta albicosta (Smith) (Lepidoptera: Noctuidae), is a pest of corn (Zea mays L.) that has recently expanded its range into Ontario, Canada. Control of S. albicosta damage to corn hybrids containing event TC1507-expressing Cry1F Bacillus thuringiensis protein alone or pyramided with event MON 89034 expressing Cry1A.105 and Cry2Ab2 Bt proteins was tested in 2011-2015 in Ontario in small- and large-scale field plots with natural infestation. In 2011, significantly lower incidence and severity of kernel damage was sustained by Cry1F × Cry1A.105 + Cry2Ab2 corn compared with a non-Bt near-isogenic hybrid. However, from 2012 to 2015, there was no difference in incidence or severity of damage comparing non-Bt hybrids with Cry1F hybrids alone or pyramided with Cry1A.105 and Cry2Ab2 planted as a pure stand or with an integrated refuge (95% Bt: 5% non-Bt seeds). In 2015, neonate larvae derived from Ontario field-collections were tested in concentration-response diet-overlay bioassays with lyophilized Cry1F protein at concentrations up to 75 µg cm-2. The concentrations at which mortality of 50% (LC50) of the collections occurred ranged from approximately 10 µg cm-2 (F0) to >28 µg cm-2 (F1) in a 7-d bioassay, indicating relative insensitivity to Cry1F. Results from field experiments, laboratory bioassays, and the history of exposure to Cry1F in corn show that S. albicosta in Ontario are not controlled by Cry1F-expressing corn hybrids and provide evidence for the conclusion that the evolution of resistance to Cry1F has occurred.

Isolation of the Male-Specific Transformer Exon as a Method for Immature Specimen Sex Identification in Chrysomya megacephala (Diptera: Calliphoridae)

Being able to efficiently differentiate between male and female individuals in the immature forms of insects allows for investigations into sexually dimorphic patterns of growth rates and gene expression. For species lacking sex-specific morphological characteristics during these periods, alternative methods must be devised. Commonly, isolation of sex determination genes reveals sex-specific band patterns and allows for markers that can be used in insect control. For blow flies, a family that includes flies of medical and forensic importance, sex has previously been identified in some members using the male-specific exon in the transformer gene. This gene is relatively conserved between members of the genera Cochliomyia and Lucilia (Diptera: Calliphoridae), and we isolated a portion of this gene in an additional forensically and medically important blow fly genus using the widespread Chrysomya megacephala (F.). We found a relatively high level of conservation between exons 1 and 2 of transformer and were able to amplify a region containing the male-specific exon in C. megacephala. A sex-specific molecular diagnostic test based on the presence of sexually dimorphic PCR product bands showed the expected genotype for adults and intrapuparial period specimens of known sex. The same result could be obtained from single third-instar larval specimens, opening up the possibility to not only determine if development rates are sex dependent, but also to investigate the development of sexually dimorphic traits of interest in C. megacephala.

Is subtyping of intestinal metaplasia in the upper gastrointestinal tract a worthwhile exercise? An evaluation of current mucin histochemical stains

Intestinal metaplasia is a premalignant condition that occurs in the upper gastrointestinal tract and can be subdivided into three types (I, II and III). Previous studies suggest that type III carries the highest cancer risk. The high iron diamine/alcian blue (HID/AB) technique traditionally has been used to identify this subtype; however, the technique uses reagents that are toxic and potentially carcinogenic. Therefore, in this study we evaluate various alternative histochemical techniques. Our results indicated that the only suitable alternative is Gomori's aldehyde fuchsin/AB technique. The study also revealed that subtyping of intestinal metaplasia is a subjective procedure, open to varying interpretation. Consequently, we suggest that previous work linking cancer risk to metaplasia subtypes should be viewed with some circumspection.

Body Size, Rather Than Male Eye Allometry, Explains Chrysomya megacephala (Diptera: Calliphoridae) Activity in Low Light

Male Chrysomya megacephala (F.) blow fly compound eyes contain an unusual area of enlarged dorsal facets believed to allow for increased light capture. This region is absent in females and has been hypothesized to aid in mate tracking in low light conditions or at greater distances. Many traits used in the attraction and capture of mates are allometric, growing at different rates relative to body size. Previous reports concerning C. megacephala eye properties did not include measurements of body size, making the relationship between the specialized eye region and body size unclear. We examined different morphological features of the eye among individuals of varying sizes. We found total eye size scaled proportionately to body size, but the number of enlarged dorsal facets increased as body size increased. This demonstrated that larger males have an eye that is morphologically different than smaller males. On the basis of external morphology, we hypothesized that since larger males have larger and a greater number of dorsally enlarged facets, and these facets are believed to allow for increased light capture, larger males would be active in lower light levels than smaller males and females of equal size. In a laboratory setting, larger males were observed to become active earlier in the morning than smaller males, although they did not remain active later in the evening. However, females followed the same pattern at similar light levels suggesting that overall body size rather than specialized male eye morphology is responsible for increased activity under low light conditions.

Impact of the Bt Corn Proteins Cry34/35Ab1 and Cry3Bb1, Alone or Pyramided, on Western Corn Rootworm (Coleoptera: Chrysomelidae) Beetle Emergence in the Field

Western corn rootworm, Diabrotica virgifera virgifera LeConte, is a major pest of corn, Zea mays L. The effect of the Bt proteins Cry34/35Ab1 and Cry3Bb1, alone or pyramided in corn hybrids on D. v. virgifera adult emergence was evaluated in field experiments for 3 yr. Experiments were infested artificially with 2,500 viable D. v. virgifera eggs per row meter of corn. The reduction in beetle emergence compared with non-Bt controls, from Cry34/35Ab1, Cry3Bb1, and the pyramided hybrids ranged from 64.3 to 97.4%, 91.1 to 95.2%, and 98.1 to 99.6%, respectively. The sex ratio of emerged beetles was usually female-biased from the Cry3Bb1 and pyramided treatments, but not from Cry34/35Ab1 treatment alone. Emergence from all Bt hybrids was delayed compared with the control, with the delay longest from the pyramided hybrid. In 2013, three egg infestation levels were tested, with density-dependent mortality observed at 1,250 viable eggs per row meter. The effect of Bt proteins on the emergence timing and sex ratio of D. v. virgifera may impact the suitability of resistance management plans, specifically the effectiveness of the refuge strategy. Susceptible males emerging from refuge might not be synchronized to mate with potentially resistant females emerging later from Bt corn hybrids.

Effect of European Chafer Larvae (Coleoptera: Scarabaeidae) on Winter Wheat and Role of Neonicotinoid Seed Treatments in Their Management

A critical density of four third-instar larvae per 900 cm2 for European chafer, Rhizotrogus (Amphimallon) majalis (Razoumowsky), in winter wheat, Triticum aestivum L., was derived from small-plot greenhouse and field experiments conducted under favorable crop growing conditions at several Ontario and Michigan locations from 2001-2003. On average, plant weight was decreased by 14% and plant stand by 11% between zero and four larvae per 900 cm2. In a commercial field under moisture stress, a yield loss of 35% occurred at a density of two third-instars per 900 cm2. In short-term greenhouse experiments, density-dependent mortality was evident, whereas low larval recovery in field experiments indicates a high level of overwintering mortality, regardless of larval density. Winter wheat seed treatments of neonicotinoid insecticides, clothianidin, imidacloprid, and thiamethoxam provided protection from damage by larvae, but the level of protection was inconsistent between greenhouse and field small plots, and there was no apparent difference in protection amongst active ingredients or between application rates. There was little evidence of larval mortality owing to seed treatment, which supports the suggestion that neonicotinoid insecticides protect seedlings from loss by a nonlethal mechanism. Overall, we estimate that a low rate of neonicotinoid insecticide used at larval densities just less than the critical density will mitigate winter wheat losses by 85%.

Perampanel, an antagonist of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors, for the treatment of epilepsy: studies in human epileptic brain and nonepileptic brain and in rodent models

Perampanel [Fycompa, 2-(2-oxo-1-phenyl-5-pyridin-2-yl-1,2-dihydropyridin-3-yl)benzonitrile hydrate 4:3; Eisai Inc., Woodcliff Lake, NJ] is an AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) receptor antagonist used as an adjunctive treatment of partial-onset seizures. We asked whether perampanel has AMPA receptor antagonist activity in both the cerebral cortex and hippocampus associated with antiepileptic efficacy and also in the cerebellum associated with motor side effects in rodent and human brains. We also asked whether epileptic or nonepileptic human cortex is similarly responsive to AMPA receptor antagonism by perampanel. In rodent models, perampanel decreased epileptic-like activity in multiple seizure models. However, doses of perampanel that had anticonvulsant effects were within the same range as those engendering motor side effects. Perampanel inhibited native rat and human AMPA receptors from the hippocampus as well as the cerebellum that were reconstituted into Xenopus oocytes. In addition, with the same technique, we found that perampanel inhibited AMPA receptors from hippocampal tissue that had been removed from a patient who underwent surgical resection for refractory epilepsy. Perampanel inhibited AMPA receptor-mediated ion currents from all the tissues investigated with similar potency (IC50 values ranging from 2.6 to 7.0 μM). Cortical slices from the left temporal lobe derived from the same patient were studied in a 60-microelectrode array. Large field potentials were evoked on at least 45 channels of the array, and 10 μM perampanel decreased their amplitude and firing rate. Perampanel also produced a 33% reduction in the branching parameter, demonstrating the effects of perampanel at the network level. These data suggest that perampanel blocks AMPA receptors globally across the brain to account for both its antiepileptic and side-effect profile in rodents and epileptic patients.

Thermal avalanches near a Mott transition

We probe the volume collapse transition (ΔV/Vo ∼ 15%) between the isostructural γ and α phases (T ∼ 100 K) of Ce0.9Th0.1 using the Hall effect, three-terminal capacitive dilatometry, and electrical resistivity measurements. Hall effect measurements confirm the itinerant ground state as the carrier concentration increases by a factor of 7 in the α phase, γ phase (nH = 5.28 × 10(26) m(-3)), and the α phase (nH = 3.76 × 10(27) m(-3)). We were able to detect a noise spectrum consisting of avalanches while slowly varying the temperature through the hysteretic region. We surmise that the avalanches originate from intergranular stresses at the interfaces between partially transformed high-volume and low-volume phases. The statistical distribution of avalanches obey power laws with energy exponent ϵ ≃ 1.5. Hall effect measurements, combined with universal critical exponents, point to short electron mean-free percolation pathways and carrier localization at phase interfaces. Carrier localization was predicted many years ago for elemental cerium by Johansson (1974 Phil. Mag. 30 469).

The fate of Lernaeocera branchialis (L.) (Crustacea; Copepoda) in Atlantic cod, Gadus morhua L

Lernaeocera branchialis, a copepod crustacean parasite of gadoids, represents a potential threat to both wild and farmed cod, Gadus morhua. The pathological changes associated with the early stages of experimental infection have previously been reported in detail, and this article describes the lesions associated with later chronic stages of experimental infection. Chronic infection is characterised by extravascular granuloma formation and proliferation of fibrovascular tissue around intact and fragmented, degenerate parasites within both the gill arch and cardiac region. The majority of parasite granulomas are located within connective tissues of the gill arch or pericardium; however, low numbers are present within the wall of large vessels. The intraluminal parasites and thrombi of early stage infection are largely absent in these later lesions. We propose that organisation and incorporation of the parasite thrombus into the vessel wall with subsequent granuloma formation and extrusion into the surrounding connective tissue leads to the elimination of the parasite from the vascular system. Thus, rather than being a negative consequence of infection thrombosis is protective, allowing the host to survive the substantial initial vascular insult.

Band structure of SnTe studied by photoemission spectroscopy

We present an angle-resolved photoemission spectroscopy study of the electronic structure of SnTe and compare the experimental results to ab initio band structure calculations as well as a simplified tight-binding model of the p bands. Our study reveals the conjectured complex Fermi surface structure near the L points showing topological changes in the bands from disconnected pockets, to open tubes, and then to cuboids as the binding energy increases, resolving lingering issues about the electronic structure. The chemical potential at the crystal surface is found to be 0.5 eV below the gap, corresponding to a carrier density of p=1.14 × 10(21)  cm(-3) or 7.2 × 10(-2) holes per unit cell. At a temperature below the cubic-rhombohedral structural transition a small shift in spectral energy of the valance band is found, in agreement with model predictions.

Heavy-electron metals: new highly correlated States of matter

Heavy-electron metals exhibit highly correlated electronic behavior at liquid helium temperatures, with conduction-electron masses some hundred times the free-electron mass. Whether "normal," antiferromagnetic, or superconducting, their electronic behavior differs drastically from their ordinary metallic counterparts. The physical origin of the large mass and unusual superconducting and magnetic properties is the strong coupling between the conduction electrons and the local f-electron moment fluctuations characteristic of these materials.

Defective insulin signaling pathway and increased glycogen synthase kinase-3 activity in the brain of diabetic mice: parallels with Alzheimer's disease and correction by insulin

We have evaluated the effect of peripheral insulin deficiency on brain insulin pathway activity in a mouse model of type 1 diabetes, the parallels with Alzheimer's disease (AD), and the effect of treatment with insulin. Nine weeks of insulin-deficient diabetes significantly impaired the learning capacity of mice, significantly reduced insulin-degrading enzyme protein expression, and significantly reduced phosphorylation of the insulin-receptor and AKT. Phosphorylation of glycogen synthase kinase-3 (GSK3) was also significantly decreased, indicating increased GSK3 activity. This evidence of reduced insulin signaling was associated with a concomitant increase in tau phosphorylation and amyloid beta protein levels. Changes in phosphorylation levels of insulin receptor, GSK3, and tau were not observed in the brain of db/db mice, a model of type 2 diabetes, after a similar duration (8 weeks) of diabetes. Treatment with insulin from onset of diabetes partially restored the phosphorylation of insulin receptor and of GSK3, partially reduced the level of phosphorylated tau in the brain, and partially improved learning ability in insulin-deficient diabetic mice. Our data indicate that mice with systemic insulin deficiency display evidence of reduced insulin signaling pathway activity in the brain that is associated with biochemical and behavioral features of AD and that it can be corrected by insulin treatment.

Imidazo[5,1-f][1,2,4]triazin-2-amines as novel inhibitors of polo-like kinase 1

The synthesis and biological activities of imidazo[5,1-f][1,2,4]triazin-2-amines (imidazotriazines) as novel polo-like kinase 1 inhibitors are reported.

Monoclonality and oligoclonality of T cell receptor beta gene in angioimmunoblastic T cell lymphoma

Angioimmunoblastic T cell lymphoma (AILT) is an aggressive T cell lymphoma with an incidence of approximately 1-2% of all non-Hodgkin lymphoma. The detection of clonal T cell receptor (TCR) gene rearrangements helps in the diagnosis of T cell malignancies such as AILT, where morphological and immunohistological investigations are not always sufficient to reach a definitive diagnosis. TCR beta (TCRB) and TCR gamma (TCRG) gene rearrangements were analysed from 17 WHO-defined cases of AILT by PCR for the presence of TCR clonality. TCRB gene rearrangements were sequenced to identify molecular signature(s) common among this patient group. Monoclonal and oligoclonal TCRB and TCRG gene rearrangements were detected in all cases. BV17S1 was slightly over-represented compared to the use of other Vbeta gene segments; however, no preferential usage of J gene segment(s) was detected. The results of this study emphasise that TCR clonality and oligoclonality is a diagnostic feature of AILT and that BV17S1 is over-represented with no other common molecular findings.

Observation of a continuous phase transition in a shape-memory alloy

Elastic neutron-scattering, inelastic x-ray scattering, specific-heat, and pressure-dependent electrical transport measurements have been made on single crystals of AuZn and Au0.52Zn0.48. Elastic neutron scattering detects new commensurate Bragg peaks (modulation) appearing at Q =(1.33,0.67,0) at temperatures corresponding to each sample's transition temperature (TM = 64 and 45 K, respectively). Although the new Bragg peaks appear in a discontinuous manner in the Au0.52Zn0.48 sample, they appear in a continuous manner in AuZn. Surprising us, the temperature dependence of the AuZn Bragg peak intensity and the specific-heat jump near TM are in favorable accord with a continuous transition. A fit to the pressure dependence of TM suggests the presence of a critical end point in the AuZn phase diagram located at TM* = 2.7 K and p* = 3.1 GPa.