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.

Thalassophilia and marine identity: Drivers of 'thick' marine citizenship

Changing humanity's relationship with the ocean is identified as one of ten key challenges in the UN Decade of Ocean Science for Sustainable Development (2021-2030). Marine citizenship is one potential policy approach for reducing anthropogenic harms to the ocean and promoting ocean recovery, and there is a need to better understand marine citizenship motivating factors and their interactions. To contribute to a more holistic understanding, we approached this problem using an interdisciplinary, mixed methodology, which prioritised the voices and experiences of active marine citizens. An online survey and semi-structured interviews were conducted to examine factors spanning environmental psychology (values, environmental identity) and human geography (place attachment and dependency). Our data uncovered a unique marine place attachment, or thalassophilia, which is a novel conceptualisation of the human capacity to bond with a type of place beyond human settlements or defined localities. It is the product of strong emotional responses to the sensorial experience of the ocean and shared social or cultural understanding of ocean place identifications. A key driver of deeper marine citizenship is marine place dependency, and it is positively influence by stimulation and non-conformity values, environmental identity, and thalassophilia. We map significant motivating factors to identity process theory and describe a novel marine identity concept. We propose this as an operational mechanism of marine citizenship action, potentially filling the value- and knowledge-action gaps in the context of marine environmental action. This research provides a cornerstone in marine citizenship research by analysing together in one study a multitude of variables, which cross human-ocean relationships and experiences. The identification and characterisation of thalassophilia and marine identity process theory will enable research and practice to move forwards with a clearer framework of the role of the ocean as a place in environmental action.

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.

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.

Abstract P1-20-03: Withdrawn

This abstract was withdrawn by the authors.

Citation Format: Dillon SR, Evans LS, Rickel E, Lewis KE, Swanson R, Levin SD, Wolfson M, Peng SL, Swiderek KM. Withdrawn [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-20-03.

The association of age with acute toxicities in NRG oncology combined modality lower GI cancer trials

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Background: This study sought to compare adverse events (AEs) of older and younger adults with lower gastrointestinal (GI) malignancies treated on NRG studies. Methods: Data from six NRG trials (RTOG 9811/0012/0247/0529/0822 & NSABP R-04), testing combined modality therapy (radiation and chemotherapy) in patients with anal or rectal cancer, were collected to test the hypothesis that older age was associated with increase in acute ( ≤ 90 days from treatment start) AEs. AEs were defined as GI, Genitourinary (GU), hematologic, or skin. AEs and compliance with protocol-directed therapy were compared between patients aged ≥ 70 years and < 70 years. Categorical variables were compared across age groups using the chi-square test. The association of age on AEs was evaluated using a covariate-adjusted logistic regression model, with odds ratio (OR) reported. To adjust for multiple comparisons, a p-value < 0.01 was considered statistically significant. Results: Data from 2525 patients were collected (43% female, 72% rectal cancer). There were 380 patients ≥ 70 years old (15%). Older patients were more likely to have worse baseline performance status (PS 1 or 2) (23% vs. 16%, p <0.01), but otherwise baseline characteristics were similar. Older patients were less likely to have completed their chemotherapy (78% vs. 87%, p < 0.01), but had similar median RT duration. On univariate analysis, patients ≥ 70 were more likely to experience grade ≥ 3 GI AEs (36% vs. 23%, OR 1.82, p < 0.001), and less likely to experience ≥ 3 skin AEs (8% vs. 14%, OR 0.56, p = 0.002). There was no difference between GU or hematologic AEs. On multivariable analysis, age ≥ 70 was associated with grade ≥ 3 GI AE (OR 1.80, 95% CI: 1.40, 2.31; p < 0.001) after adjusting for gender, PS, T stage, disease site, RT duration, and chemotherapy completion. Conclusions: Older patients with curable lower GI cancers who underwent combined-modality therapy were less likely to complete chemotherapy and were more likely to experience serious GI toxicity, whereas younger patients had higher rates of serious skin AEs.

Critical research needs for managing coral reef marine protected areas: perspectives of academics and managers

Marine protected areas (MPAs) are a primary policy instrument for managing and protecting coral reefs. Successful MPAs ultimately depend on knowledge-based decision making, where scientific research is integrated into management actions. Fourteen coral reef MPA managers and sixteen academics from eleven research, state and federal government institutions each outlined at least five pertinent research needs for improving the management of MPAs situated in Australian coral reefs. From this list of 173 key questions, we asked members of each group to rank questions in order of urgency, redundancy and importance, which allowed us to explore the extent of perceptional mismatch and overlap among the two groups. Our results suggest the mismatch among MPA managers and academics is small, with no significant difference among the groups in terms of their respective research interests, or the type of questions they pose. However, managers prioritised spatial management and monitoring as research themes, whilst academics identified climate change, resilience, spatial management, fishing and connectivity as the most important topics. Ranking of the posed questions by the two groups was also similar, although managers were less confident about the achievability of the posed research questions and whether questions represented a knowledge gap. We conclude that improved collaboration and knowledge transfer among management and academic groups can be used to achieve similar objectives and enhance the knowledge-based management of MPAs.

Chemical characterization of a hormone that promotes cell arrest in g2 in complex tissues

A G(2|)factor in the cotyledons of Pisum sativum, which arrests the growth of cells in both roots and shoots in the G(2) stage of the cell cycle, has been isolated and identified as trigonelline (N-methylnicotinic acid). To our knowledge, trigonelline is the first hormone that effects cell arrest in complex tissues of plants and animals to be chemically identified.

Transformed follicular lymphoma: the 25-year experience of a UK provincial lymphoma treatment centre

Follicular lymphoma can transform into diffuse large B cell lymphoma, which is usually associated with rapid disease progression, refractoriness to treatment and a poor outcome. We report the 25-year unselected experience of a UK provincial lymphoma treatment centre. This comprises of one of the largest series ever studied. Sixty-three patients were identified (56 initially presented as follicular lymphoma, 5 with 'transformed' lymphoma and 2 with follicular and transformed lymphoma from different biopsy sites). The median age at presentation was 54 years (range 32-76). The median time to transformation was 43 months (range 0-172). For all patients, the median overall survival was 76 months (range 8-254) and from transformation 10 months (range 1-166); 46 of 63 patients have died. For those whose transformation was initially treated with CHOP chemotherapy 10 were in complete remission (CR) and 14 were deceased (median survival 24, range 2-114 months). Five patients had high-dose chemotherapy and 3 were alive (at 25, 36 and 137 months). We conclude that CHOP chemotherapy (probably with rituximab) is a reasonable first treatment in fit patients and high dose chemotherapy with autologous stem cell support deserves further study.

Poor outcome in adolescents with high-risk Hodgkin lymphoma

This retrospective study looks at the differences between adolescents (15-19 years) and young adults (20-25 years), diagnosed with Hodgkin lymphoma and treated at the same adult institution. Outcome according to risk category was evaluated, and although there were no significant differences in the whole cohort, or low and intermediate-risk categories, high-risk adolescent patients had a significantly worse outcome compared to that of young adults. In these high-risk patients, 5-year event free survival was 43.6% in adolescents compared to 58.7% in young adults (log-rank survival p=0.03), and the 5-year overall survival in adolescents was 66.7% compared to 84.4% in the young adults (p=0.04). Possible contributing factors to this inferior outcome in these high-risk patients were explored. The difference could not be explained in terms of differences in histological subtype (p=0.5), proportion of patients with bulky (p=0.6) or extranodal disease (p=0.6), initial treatment received (chemotherapy alone compared to combination therapy, p=0.2), or proportion proceeding to high-dose treatment after initial treatment failure (p=0.6). There was no difference in the documented number of delays, dose reductions or episodes of non-compliance during initial treatment in the two high-risk age groups. A significantly greater proportion of high-risk adolescents had primary progressive disease (PPD) [eight high-risk adolescents (33.3%) compared to two high-risk young adults (7.7%), p=0.02].

High-dose chemotherapy and peripheral blood stem cell support in refractory gestational trophoblastic neoplasia

We present retrospectively our experience in the use of high-dose chemotherapy and haematopoietic stem cell support (HSCS) for refractory gestational trophoblastic neoplasia (GTN) in the largest series so far reported. In all, 11 patients have been treated at three Trophoblast Centres between 1993 and 2004. The conditioning regimens comprised either Carbop-EC-T (carboplatin, etoposide, cyclophosphamide, paclitaxel and prednisolone) or CEM (carboplatin, etoposide and melphalan) or ICE (ifosfamide, carboplatin, etoposide). Two patients had complete human chorionic gonadotrophin responses, one for 4 and the other for 12 months. Three patients had partial tumour marker responses for 1–2 months. High-dose chemotherapy and HSCS for GTN is still unproven. Further studies are needed, perhaps in high-risk patients who fail their first salvage treatment.

Development of a CTL vaccine for Her-2/neu using peptide-microspheres and adjuvants

With the ultimate goal of developing a therapeutic cancer vaccine, we encapsulated the Her-2/neu peptide p369-377 in poly(lactide-co-glycolide) microspheres. This formulation was found to effectively elicit CD8+ cytotoxic T cell (CTL) responses in an HLA-A*0201 transgenic mouse model. In contrast, immunization with either peptide alone or peptide formulated in incomplete Freund's adjuvant (IFA) failed to elicit such CTL responses. Responses induced by the peptide-microsphere formulation were found to peak at approximately 6 weeks post-immunization, and were enhanced by delivering increased doses of peptide and with repeated administrations over time. Co-administration of the peptide-microspheres with adjuvants, including granulocyte-macrophage colony stimulating factor, MPL adjuvant and select synthetic Toll-Like Receptor 4 ligands, the aminoalkyl glucosaminide-4 phosphates, significantly augmented CTL responses. These studies provide important guidance for the design of human clinical trials of microsphere vaccines in terms of optimal peptide-microsphere formulation, vaccination regimen, vaccine dose, and adjuvant selection.

Diversity of cell lengths in terminal portions of roots: implications to cell proliferation

Terminal meristems are responsible for all primary growth of roots. It has been asserted that all cells of root meristems are actively dividing (no cells cycle slowly or arrest in the cycle) and stem cell populations expand exponentially. Because cells do not slide relative to each other in roots, relative cell lengths may be used to determine relative cell cycle durations and/or proportions of cells actively dividing in root tissues. If all cells are cycling, no interphase cells should be longer than critical length (length of longest mitotic cell in the meristem) and cells should exhibit an exponential cell-age distribution. Lengths of all cells were obtained radially across entire median longitudinal root sections at 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 mm from the founder cell/root cap boundary for five plant species to estimate percentages of cells longer than critical length. For example, up to 15 and 90% of all interphase cells were longer than critical length in 0.5 and 2.0 mm tissues, respectively, indicating that slow-cycling and/or non-proliferative cells are present in such tissues. In order to determine if the distribution of cell lengths in 0.5 mm segments approximated an exponential cell-age distribution, lengths of interphase cells less than critical length were determined. Such interphase cells were placed into ten groups according to cell length and percentages of cells in each group were compared with percentages of cells in groups calculated from an exponential cell-age distribution. Percentages of cells were significantly different from predicted percentages of between 6 and 9 out of ten groups - cell lengths were not distributed exponentially. Because there are significant numbers of interphase cells longer than critical length and since lengths of interphase cells shorter than critical length do not resemble an exponential cell-age distribution, it must be concluded that not all cells in root segments from 0.5 to 3.0 mm root segments are actively dividing. Heretofore, no databases of cell lengths have been used to test these assertions.

Compressive/Tensile Stresses and Lignified Cells as Resistance Components in Joints between Cladodes of Opuntia laevis (Cactaceae)

The Cactaceae are a diverse group of plants with a wide variety of morphologies. Many species of Opuntia have segmented stems in which terminal cladodes may be separated from main-stem cladodes with varying amounts of resistance. From a geometric approach, derivations were used to calculate normal (axial and bending) and shear (transverse force and torque) stresses at joints due to the weight of the cladodes. Normal and shear stresses act perpendicular and parallel to (along) the cross sections of joints, respectively. Normal stress caused by bending was >10 times that of the mean value of any other stress. Analyses were performed to determine the relationship between maximum normal stress and the amount of lignified xylem cells. Such cells had thicker cell walls compared with the various other cells of stem joints that had thin cell walls and that thus would provide the most resistance to normal stresses. An analogy was made between cactus joints and a composite beam with reinforcing rods. In such joints, thin-walled parenchyma cells might be analogous to concrete that has little resistance to tensile stress, while the thick-walled, lignified xylem cells would be analogous to reinforcing rods. There were statistically significant relationships between normal stresses (from bending and axial loads) and mean percentage of lignified xylem cells (r=0.73) and between normal stresses and total areas of lignified xylem cells (r=0.65) (more stress, more reinforcing xylem cells). Tensile portions of cactus joints had 23% lignified xylem cells, while compressive portions had only 10% lignified xylem cells in joint areas (more tension, more reinforcing xylem cells). In addition, tensile joint tissues had two to three times more thick-walled, lignified xylem cells in the outer 30% of the radius compared with other joint tissues types (more reinforcing near the surface). To our knowledge, this is the first publication to present mechanical stresses at stem joints of cacti and the first to relate these stresses to characteristics of resisting tissues in the joints of a cactus.

Expression of chimeric granulocyte-macrophage colony-stimulating factor/interleukin 2 receptors in human cytotoxic T lymphocyte clones results in granulocyte-macrophage colony-stimulating factor-dependent growth

Adoptive immunotherapy with ex vivo-expanded antigen-specific cytotoxic T lymphocytes (CTLs) has been shown to clear viral infections and eliminate tumors in murine models. Clinical trials have also reported promising data for the use of adoptive immunotherapy to treat cytomegalovirus (CMV) and Epstein-Barr viral (EBV) infections in bone marrow transplant recipients. For these indications, the need for ex vivo-expanded CTLs is often short lived, until the immune system is reconstituted by the donor transplant. In chronic disease settings, increased longevity of adoptively transferred CTLs and generation of memory will be necessary. The additional administration of helper functions normally supplied by antigen-specific T helper (Th) cells will probably be essential for long-term survival of adoptively transferred CTLs. Toward this goal of supplying helper functions, we transduced human CTLs with chimeric GM-CSFR/IL-2R receptors that deliver an IL-2 signal on binding GM-CSF. Clones expressing the chimeric receptors proliferated in response to GM-CSF. Stimulation with antigen induced GM-CSF production and resulted in an autocrine growth loop such that the CTL clones proliferated in the absence of exogenous cytokines. This type of genetic modification has potential for increasing the circulating half-life and, by extension, the efficacy of ex vivo-expanded CTLs.

The effect of prostaglandin E1 on liver adenine nucleotides and cytoplasmic enzymes in a porcine model of normothermic hepatic ischemia

The liver has been judged relatively resistant to ischemia, but prolonged inflow occlusion at normothermic conditions can produce evidence of reversible or irreversible hepatocellular damage. Cytoprotective agents have been used both experimentally and clinically to afford extended viability of hepatocytes under reduced perfusion. One agent, prostaglandin E1, has been described clinically as effective in sustaining liver function under ischemic conditions. We have sought to verify this observation in an experimental model using prolonged normothermic inflow occlusion. Twenty miniature pigs were anesthetized and subjected to subtotal normothermic hepatic inflow occlusion (portal vein, hepatic artery, choledochal vessels) to allow for sufficient splanchnic decompression. Half of the animals received pretreatment with prostaglandin E1 (alprostadil) 500 micrograms intravenously. Inflow occlusion was maintained for 2 hours followed by reperfusion and killing 24 hours later. As a measure of functional preservation, the tissue adenine nucleotides adenosine monophosphate, diphosphate, and triphosphate (AMP, ADP, ATP) were measured in ischemic liver by freeze-clamping and high-performance liquid chromatography during occlusion and after reperfusion. Cytosolic enzyme determinations (aspartate transaminase, alanine transaminase, lactate dehydrogenase) were also made before occlusion and after reperfusion. As a possible indicator of cellular injury, blood ionized Ca++ was measured before inflow occlusion and after reperfusion. Although no difference was found in levels of AMP and ADP between prostaglandin E1 and control animals, ATP levels rose significantly higher during recovery in prostaglandin E1 animals at 60 minutes and 24 hours after reperfusion (13.97 +/- 1.29 and 13.60 +/- 0.91 mumoles/gm dry weight prostaglandin E1 vs. 9.25 +/- 0.97 and 9.80 +/- 0.85 mumoles/gm dry weight co control, P < .01).(ABSTRACT TRUNCATED AT 250 WORDS)

Depth of anisometropic amblyopia and difference in refraction

Disagreement exists as to whether the depth of anisometropic amblyopia correlates with the degree of anisometropia. We reviewed the charts of 303 consecutive patients with the diagnosis of amblyopia. Thirty-five patients with untreated anisometropia without strabismus were identified. The best-corrected visual acuities, manifest refractions, and autorefractions were recorded. The differences in spherical equivalent, root mean square, and an index of anisometropia, which we defined, were calculated. The depth of amblyopia was strongly correlated to all three measures of anisometropia for both hyperopic and myopic individuals. Our new index of anisometropia was an excellent predictor of the depth of amblyopia.

Diagnosis and treatment of retrobulbar hemorrhage

Complete loss of light perception in an eye is one of the most severe complications of maxillofacial surgery. Although irreversible in many cases, early recognition and prompt intervention may improve the final outcome. The purpose of this article is to review the etiology and pathophysiology of retrobulbar hemorrhage, and discuss its diagnosis and management.

Comparison of three methods of estimating the parameters of the Naka-Rushton equation

The Naka-Rushton equation empirically describes the amplitude R of the dark-adapted electroretinogram b-wave, as a function of stimulus luminance L, as R/Rmax = Ln/(Ln + Kn). Estimating the three parameters Rmax, n, and K of this function from electroretinogram data is of both experimental and clinical interest. Several different approaches have been developed to accomplish this analysis, but these approaches may derive different estimates of the three parameters. To examine this possibility, we compared the results of three methods of fitting the Naka-Rushton equation to data sets obtained from 30 normal subjects. Two methods were nonlinear curve-fitting programs; the third method involved fitting a regression line to transformed data. The results indicate that solutions provided by these methods have consistent differences, which may be an important consideration when comparing results reported in studies that used different curve-fitting methods.

The occurrence and management of esophageal fistulas resulting from Hodgkin's disease

At their radiation therapy (RT) department, the authors saw a young woman with an esophageal fistula from Hodgkin's disease that was not responsive to chemotherapy; this prompted a review of the literature concerning such patients. Twenty-two patients with Hodgkin's disease and esophageal fistula were found to have been reported previously. Most patients had active disease at the fistula site, and most who were treated with RT or chemotherapy had prompt fistula closure. Fistula formation as a complication of RT for Hodgkin's disease was found to be an extremely unusual occurrence.

Effects of topical suprofen and flurbiprofen on the miosis produced by anterior chamber irrigation with cholinergic agonists

Pretreatment with topical nonsteroidal anti-inflammatory drugs is common practice to maintain maximal pupil dilation for cataract surgery. Most surgeons also inject a cholinergic agent intracamerally for miosis after intraocular lens insertion. We evaluated the effects of topical suprofen and flurbiprofen on the miosis induced by anterior chamber irrigation with either acetylcholine or carbachol. One eye of 30 pigmented rabbits was dilated with cyclopentolate HCl and phenylephrine HCl. Three groups, each composed of ten eyes, received flurbiprofen, suprofen, or a control. In each group, five eyes received acetylcholine by anterior chamber irrigation and five received carbachol. Pupil diameters were measured with calipers before and five minutes after irrigation by an observer unaware of the treatment regimen. Irides irrigated with carbachol constricted less than those irrigated with acetylcholine (P = .016). In anterior chambers irrigated with carbachol, suprofen was associated with less miosis than either tears (P = .005) or flurbiprofen (P = .009); however, if the infusion was performed with acetylcholine, no differences between the three groups were noted (P = .44).

Yields of field-grown soybeans exposed to simulated acidic deposition

Rainfall acidity response functions for crop yield and growth are necessary to predict the overall impacts on crop yields of ambient and/or anticipated levels of acidic rain. The experiment described herein was performed at Brookhaven National Laboratory during 1984 and 1985 to determine the effects of simulated rainfalls of pH 5.6, 4.4, 4.1 and 3.3 on seed yields of four cultivars of field-grown soybeans (Glycine max Merrill). Soybeans were chosen because previous results suggested that certain varieties of this crop are sensitive to rainfall acidity and because they are an economically important crop in the USA. Sixteen plots per treatment were used. Plants were grown using standard agronomic practices under automatically movable exclusion shelters which minimize changes in the plant's microclimate. Analysis of variance of seed yields of the four cultivars showed significant treatments for all four cultivars. For all cultivars, seed yields were lower when exposed to simulated rainfalls of pH 4.4, 4.1 and 3.3 compared with rainfalls of pH 5.6. Compared with pH 5.6 rainfall (controls), yields of Amsoy exposed to pH 4.4, 4.1 and 3.3 were lower by 13, 11 and 12%, respectively. The percentage yield reductions for Asgrow, Corsoy and Hobbit were not as great as those of Amsoy. Averaged over all cultivars tested, there was a 9% seed reduction for plants exposed to simulated rain at pH 4.1 (comparable to ambient) compared with pH 5.6.

Concomitant 5-fluorouracil, mitomycin-C, and radiotherapy for advanced gynecologic malignancies

Advanced gynecologic neoplasms continue to pose major therapeutic problems; 22,500 deaths were estimated for 1987. Between December 1983 and October 1985, there were 25 patients evaluated at our institution who on joint evaluation by the radiation oncologist and gynecologic oncologists were found to have extensive disease not amenable to standard therapy. Patients were to be treated by a combined modality approach with Mitomycin-C and 5-Fluorouracil given concomitantly with radiotherapy. Nineteen patients were treated definitively and six patients were treated with palliative intent (24 primary, 1 recurrent). The patients ranged in age from 27 to 90 years with a mean of 57.3 and a median of 57. Primary sites at presentation were: cervix--14 patients, vagina--7 patients, and vulva--4 patients. The initial FIGO stages at time of the initial diagnosis were: Stage I--1 (recurrent), Stage II--4, Stage III--15, and Stage IV--5. Chemotherapy consisted of 5-fluorouracil 1 gm/m2 given continuous infusion for 4 days with Mitomycin-C 10 mg/m2 IV push on day 1. Radiation therapy was started on day 1. Only 2 of 25 patients (8%) required chemotherapy reductions. All 25 patients received mega-voltage irradiation. The external beam dose range was 2000-6500 cGy and 14/25 patients received intracavitary or interstitial therapy. In the definitive patient group, there was no reduction in the therapeutic dose. Only four patients underwent surgical therapy. With a minimum follow-up of 8 months and a median follow-up of 28 months, the survival for the entire population was 56%. Fourteen of the 19 patients (74%) treated definitively are surviving with 12 patients having no evidence of disease. Survival by site in the definitive therapy group was cervix--70%, vulva--100%, and vagina--66%. The overall response rate was 84% at 3 and 9 months (3 months; CR--36%, PR--48%, and 9 months; CR--60%, PR--24%). There were no local recurrences in the 12 patients who achieved a complete response. Three patients died of metastatic disease alone and the overall local control was 60%. Evaluation of therapeutic side effects was performed. Hematologic analysis by the Southeastern Oncology Group criteria showed neutropenia in 14 patients (1--life-threatening, 2--severe, and 11 patients--mild/moderate) and thrombocytopenia was observed in 11 patients (all mild or moderate). All hematologic complications resolved. Acute complications did not appear increased except for the addition of mild oral mucositis (12 patients). Six patients demonstrated late effects with only 2 patients felt to have severe complications.(ABSTRACT TRUNCATED AT 400 WORDS)

Socioeconomic aspects of hepatic transplantation

The outcome, cost, length of hospital stay, and extent of rehabilitation were assessed in a series of 55 consecutive patients who received hepatic transplants between May 1982 and June 1985. In the same geographic region, medical costs for patients dying of hepatic failure without transplantation were studied for years 1979 through 1984. One-yr survival in all patients transplanted without cancer was 71%, and the mean cost was $92,866. The mean cost of hospitalization for the last 12 months of life in patients who did not receive transplants was $45,643. Eight-two percent of patients surviving the first yr are fully rehabilitated and restored to pre-illness activity. Length of hospital stay, hospital costs, and the extent of rehabilitation closely correlate with a grading system based on preoperative medical status. We conclude that hepatic transplantation restores high-quality, useful life to patients with endstage liver disease in a predictable and cost-effective manner.

Acidosis as a presenting feature of chloramphenicol toxicity

Metabolic acidosis has previously been described in the gray baby syndrome, but has not been documented as a presenting feature. Four seriously ill children (bronchiolitis, hypoaldosteronism, dysautonomia, Reye syndrome), ages 4 months to 11 years, received chloramphenicol (CAP) intravenously. After initial stabilization, unexplained metabolic acidosis occurred 40 to 81 hours after beginning CAP. Serum CAP concentrations were 84, 62, 80, and 30 micrograms/ml, respectively, when acidosis was recognized. Hypotension, hypothermia, and abdominal distension occurred a mean of 23 hours after the onset of acidosis. Acidosis resolved and signs of the gray baby syndrome cleared with the decrease in serum CAP concentrations. Metabolic acidosis should be considered an early sign of CAP toxicity, and CAP should be used in reduced doses in severely ill patients, especially those with liver dysfunction.

Hereditary macular dystrophies in relation to radionuclide ocular scintigraphy

Radionuclide ocular scintigraphy was investigated to determine whether it could detect blood-retinal barrier disruption secondary to retinal disease. Patients were examined who had hereditary macular dystrophies and good correlations were found of the dynamic and equilibrium results obtained on scintigraphy with the clinical disease state. This test may hold promise as another measurement of the disruption of ocular physiology in retinal diseases.

Oculomotor nuclear complex infarction. Clinical and radiological correlation

We describe a patient with an isolated mesencephalic dorsal tegmental infarct affecting the oculomotor nuclear complex and medial longitudinal fasciculus, documented by high-resolution computed tomography, after undergoing percutaneous transluminal coronary artery angioplasty. Clinically, the patient exhibited bilateral ptosis, bilateral internuclear ophthalmoplegia, transient convergence retractory nystagmus, and minimal somnolence. We believe the combined clinical and radiological findings favor the presence of a caudal, dorsal, and paramedian embolic infarct in the territory of the paramedian branches of the mesencephalic artery as the most likely mechanism for these exceptional findings and correlate them with Warwick's scheme of the oculomotor subnuclei.

The use of radionuclide retinal scintigraphy for the assessment of retinopathy in diabetes mellitus

A computerized radiotracer technique for the detection of loss of retinal vascular integrity secondary to diabetes is presented. Radionuclide retinal scintigraphy with Technetium-99m DTPA was performed on 40 insulin-dependent diabetics and 10 nondiabetics. A ratio of eye to brain activity was used to eliminate errors associated with absolute counting. Ratios were found to be significantly higher in diabetics, especially those with active neovascularization. This technique may prove useful in the assessment and staging of eyes prone to retinopathy.

The relationship between soft tissue anomalies around the orbit and globe and astigmatic refractive errors: a preliminary report

Corneoscleral limbal masses were created in ten rabbit eyes and upper eyelid colobomas were produced in an additional ten eyes. The resultant changes in corneal curvature were recorded over a one-month period using streak retinoscopy and photokeratometry. By these methods, we have determined that forces at or near the corneoscleral limbus can produce changes in the corneal curvature that lead to refractive errors primarily of the astigmatic variety. There is a shift of the axis of astigmatism towards the meridian 90 degrees away from the external force or an increase of astigmatism along the meridian where the force was exerted. In this study, corneal curvature changed significantly in the coloboma and epibulbar mass groups when compared to the control group. This study supported a causal relationship between soft tissue anomalies and astigmatic refractive errors seen clinically in certain syndromes, such as Goldenhar and mandibulo-facial dysostosis. These findings suggest that patients observed with periorbital soft tissue defects may be at risk for the development of unilateral anisometropic refractive errors and secondary amblyopia. Recognition of this entity is essential in order that adequate therapy can be instituted at an early age.

Calibration error in dark adaptometer

We noted that the adjustable fixation device present on some models of the Goldmann-Weekers dark adaptometer has a calibration error that results in a consistent and predictable overestimation of retinal eccentricity. The error occurs because the eye being tested is not in the geometric center of the projection sphere. The true retinal locus may be computed by trigonometric analysis. A conversion table is available for reference.