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One of the oldest problems in physics is that of calculating the motion of N particles under a specified mutual force: the N -body problem. Much is known about this problem if the specified force is non-relativistic gravity, and considerable progress has been made by considering the problem in one spatial dimension. Here, I review what is known about the relativistic gravitational N -body problem. Reduction to one spatial dimension has the feature of the absence of gravitational radiation, thereby allowing for a clear comparison between the physics of one-dimensional relativistic and non-relativistic self-gravitating systems. After describing how to obtain a relativistic theory of gravity coupled to N point particles, I discuss in turn the two-body, three-body, four-body, and N -body problems. Quite general exact solutions can be obtained for the two-body problem, unlike the situation in general relativity in three spatial dimensions for which only highly specified solutions exist. The three-body problem exhibits mild forms of chaos, and provides one of the first theoretical settings in which relativistic chaos can be studied. For N≥4, other interesting features emerge. Relativistic self-gravitating systems have a number of interesting problems awaiting further investigation, providing us with a new frontier for exploring relativistic many-body systems.

We evaluate here the quantum gravity partition function that counts the dimension of the Hilbert space of a simply connected spatial region of a fixed proper volume in the context of Lovelock gravity, generalizing the results for Einstein gravity. It is found that there are sphere saddle metrics for a partition function at a fixed spatial volume in Lovelock theory. Those stationary points take exactly the same forms as in Einstein gravity. The logarithm of Z corresponding to a zero effective cosmological constant indicates that the Bekenstein-Hawking entropy of the boundary area and that corresponding to a positive effective cosmological constant points to the Wald entropy of the boundary area. We also show the existence of zeroth-order phase transitions between different vacua, a phenomenon distinct from Einstein gravity.

By respecting the conformal symmetry of the dual conformal field theory, and treating the conformal factor of the Anti-de Sitter boundary as a thermodynamic parameter, we formulate the holographic first law that is exactly dual to the first law of extended black hole thermodynamics with variable cosmological constant but fixed Newton's constant.

In this Letter, employing the generalized off-shell free energy, we treat black hole solutions as defects in the thermodynamic parameter space. The results show that the positive and negative winding numbers corresponding to the defects indicate the local thermodynamical stable and unstable black hole solutions, respectively. The topological number defined as the sum of the winding numbers for all the black hole branches at an arbitrary given temperature is found to be a universal number independent of the black hole parameters. Moreover, this topological number only depends on the thermodynamic asymptotic behaviors of the black hole temperature at small and large black hole limits. Different black hole systems are characterized by three classes via this topological number. This number could help us in better understanding the black hole thermodynamics and, further, shed new light on the fundamental nature of quantum gravity.

We present a new operational framework for studying "superpositions of spacetimes," which are of fundamental interest in the development of a theory of quantum gravity. Our approach capitalizes on nonlocal correlations in curved spacetime quantum field theory, allowing us to formulate a metric for spacetime superpositions as well as characterizing the coupling of particle detectors to a quantum field. We apply our approach to analyze the dynamics of a detector (using the Unruh-deWitt model) in a spacetime generated by a Banados-Teitelboim-Zanelli black hole in a superposition of masses. We find that the detector exhibits signatures of quantum-gravitational effects corroborating and extending Bekenstein's seminal conjecture concerning the quantized mass spectrum of black holes in quantum gravity. Crucially, this result follows directly from our approach, without any additional assumptions about the black hole mass properties.

Introduction: American adolescents continue to show a strong social media presence. This presence entails consistent monitoring of how they present themselves, and how that presentation compares to others, which in turn impacts the versions of the self they share with others. These versions include their hoped for (e.g. high academic achiever) or feared selves (e.g. inconsistent academic achiever) which have been referred to as possible selves. Here, we explored the contributions of social media use, self-presentation, social comparison, and self-esteem on adolescents' reflection of their possible selves. We also examined age as a factor to determine whether early and late adolescents reflect on and craft their social media presence in similar fashions. Ideally, all adolescents would seek to share a balance of possible selves whereby their social media presence includes both a hoped for self and a feared self in the same aspect of their lives (e.g. academic achievement and failure). These balances have been linked to positive outcomes in offline contexts., Methods: We explored the relative contributions of age, self-esteem, social media use, online self-presentation behaviors, and online social comparison tendencies to the ideation of balanced possible selves among 152 adolescents aged 11 to 18 years (55.9% female). We also included an exploratory analysis of gender differences within the content of possible selves reported., Results: The results of a sequential regression analysis, regressing the balance of possible selves on each of the independent variables, yielded no significant differences. A chi square analysis, however, revealed differences among males and females in the content of feared selves as female participants reported more feared selves involving interpersonal relationships than males., Conclusion: Further exploration of possible selves in the digital context is warranted given our findings that adolescent females, in particular, focus on interpersonal relationships as they develop their self-esteem and self-concept., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Accelerating supermassive black holes, connected to cosmic strings, could contribute to structure formation and get captured by galaxies if their velocities are small. This would mean that the acceleration of these black holes is small, too. Such a slow acceleration has no significant effect on the shadow of such supermassive black holes. We also show that, for slowly accelerating black holes, the angular position of images in the gravitational lensing effects does not change significantly. We propose a method to observe the acceleration of these black holes through gravitational lensing. The method is based on the observation that differential time delays associated with the images are substantially different with respect to the case of nonaccelerating black holes.

We reconsider the thermodynamics of anti-de Sitter black holes in the context of gauge-gravity duality. In this new setting, where both the cosmological constant Λ and the gravitational Newton's constant G are varied in the bulk, we rewrite the first law in a new form containing both Λ (associated with thermodynamic pressure) and the central charge C of the dual conformal field theory and their conjugate variables. We obtain a novel thermodynamic volume, in turn leading to a new understanding of the Van der Waals behavior of charged anti-de Sitter black holes in which phase changes are governed by the degrees of freedom in the conformal field theory. Compared to the "old" P-V criticality, this new criticality is "universal" (independent of the bulk pressure) and directly relates to the thermodynamics of the dual field theory and its central charge.

The isotropy of space is not a logical requirement but rather is an empirical question; indeed there is suggestive evidence that universe might be anisotropic. A plausible source of these anisotropies could be quantum gravity corrections. If these corrections happen to be between the electroweak scale and the Planck scale, then these anisotropies can have measurable consequences at short distances and their effects can be measured using ultra sensitive condensed matter systems. We investigate how such anisotropic quantum gravity corrections modify low energy physics through an anisotropic deformation of the Heisenberg algebra. We discuss how such anisotropies might be observed using a scanning tunnelling microscope.

We study the holographic complexity conjectures for rotating black holes, uncovering a relationship between the complexity of formation and the thermodynamic volume of the black hole. We suggest that it is the thermodynamic volume and not the entropy that controls the complexity of formation of large black holes in both the complexity equals action and complexity equals volume proposals in general. Our proposal reduces to known results involving the entropy in settings where the thermodynamic volume and entropy are not independent, but has broader scope. Assuming a conjectured inequality is obeyed by the thermodynamic volume, we establish that the complexity of formation is bounded from below by the entropy for large black holes.

Quantum field theory is completely characterized by the field correlations between spacetime points. In turn, some of these can be accessed by locally coupling to the field simple quantum systems, also known as particle detectors. In this letter we consider what happens when a quantum-controlled superposition of detectors at different space-time points is used to probe the correlations of the field. We show that, due to quantum interference effects, two detectors can gain information on field correlations that would not be accessible, otherwise. This has relevant consequences for information theoretic quantities, like entanglement and mutual information harvested from the field. In particular, the quantum control allows for extraction of entanglement in scenarios where this is, otherwise, provably impossible.

The Ruppeiner geometry of thermodynamic fluctuations provides a powerful diagnostic of black hole microstructures. We investigate this for charged anti-de Sitter black holes and find that, while an attractive microstructure interaction dominates for most parameter ranges, a weak repulsive interaction dominates for small black holes of high temperature. This unique property distinguishes the black hole system from that of a van der Waals fluid, where only attractive microstructure interactions are found. We also find two other novel universal properties for charged black holes. One is that the repulsive interaction is independent of the black hole charge and temperature. The other is that the behavior of the Ruppeiner curvature scalar near criticality is characterized by a dimensionless constant that is identical to that for a van der Waals fluid, providing us with new insight into black hole microstructures.

We present several results concerning the free energy of odd-dimensional conformal field theories (CFTs) on squashed spheres. First, we propose a formula which computes this quantity for holographic CFTs dual to higher-curvature gravities with second-order linearized equations of motion. As opposed to standard on-shell action methods for Taub geometries, our formula only involves a simple evaluation of the corresponding bulk Lagrangian on an auxiliary pure anti-de Sitter (AdS) space. The expression is closely related to the function determining the possible AdS vacua of the bulk theory in question, which we argue to act as a generating functional from which correlation functions of the boundary stress tensor can be easily characterized. Finally, based on holographic results and free-field numerical calculations, we conjecture that the subleading term in the squashing-parameter free-energy expansion is universally controlled by the stress-tensor three-point function charge t_{4} for general (2+1)-dimensional CFTs.

This corrects the article DOI: 10.1038/ncomms5997.

We construct asymptotically safe extensions of the standard model by adding gauged vectorlike fermions. Using large number-of-flavor techniques we argue that all gauge couplings, including the hypercharge and, under certain conditions, the Higgs coupling, can achieve an interacting ultraviolet fixed point.

We present what we believe is the first example of a "λ-line" phase transition in black hole thermodynamics. This is a line of (continuous) second order phase transitions which in the case of liquid ^{4}He marks the onset of superfluidity. The phase transition occurs for a class of asymptotically anti-de Sitter hairy black holes in Lovelock gravity where a real scalar field is conformally coupled to gravity. We discuss the origin of this phase transition and outline the circumstances under which it (or generalizations of it) could occur.

We construct a new class of rotating anti-de Sitter (AdS) black hole solutions with noncompact event horizons of finite area in any dimension and study their thermodynamics. In four dimensions these black holes are solutions to gauged supergravity. We find that their entropy exceeds the maximum implied from the conjectured reverse isoperimetric inequality, which states that for a given thermodynamic volume, the black hole entropy is maximized for Schwarzschild-AdS space. We use this result to suggest more stringent conditions under which this conjecture may hold.

Hidden-variable models aim to reproduce the results of quantum theory and to satisfy our classical intuition. Their refutation is usually based on deriving predictions that are different from those of quantum mechanics. Here instead we study the mutual compatibility of apparently reasonable classical assumptions. We analyze a version of the delayed-choice experiment which ostensibly combines determinism, independence of hidden variables on the conducted experiments, and wave-particle objectivity (the assertion that quantum systems are, at any moment, either particles or waves, but not both). These three ideas are incompatible with any theory, not only with quantum mechanics.

Wave-particle duality, superposition and entanglement are among the most counterintuitive features of quantum theory. Their clash with our classical expectations motivated hidden-variable (HV) theories. With the emergence of quantum technologies, we can test experimentally the predictions of quantum theory versus HV theories and put strong restrictions on their key assumptions. Here, we study an entanglement-assisted version of the quantum delayed-choice experiment and show that the extension of HV to the controlling devices only exacerbates the contradiction. We compare HV theories that satisfy the conditions of objectivity (a property of photons being either particles or waves, but not both), determinism and local independence of hidden variables with quantum mechanics. Any two of the above conditions are compatible with it. The conflict becomes manifest when all three conditions are imposed and persists for any non-zero value of entanglement. We propose an experiment to test our conclusions.

We consider the generation of dark matter mass via radiative electroweak symmetry breaking in an extension of the conformal standard model containing a singlet scalar field with a Higgs portal interaction. Generating the mass from a sequential process of radiative electroweak symmetry breaking followed by a conventional Higgs mechanism can account for less than 35% of the cosmological dark matter abundance for dark matter mass M(s)>80 GeV. However, in a dynamical approach where both Higgs and scalar singlet masses are generated via radiative electroweak symmetry breaking, we obtain much higher levels of dark matter abundance. At one-loop level we find abundances of 10%-100% with 106 GeV80 GeV detection region of the next generation XENON experiment.

An altered anti-Epstein-Barr virus (EBV) serologic profile preceding diagnosis is associated with an increased risk of Hodgkin lymphoma. It is unknown whether this atypical pattern predicts Hodgkin lymphoma risk further subdivided by determination of EBV in tumor cells. A nested case-control study of 128 incident Hodgkin lymphoma cases and 368 matched controls from active-duty military personnel with archived serum in the US Department of Defense Serum Repository was conducted to determine whether a panel of anti-EBV antibody titers differed in EBV(+) and EBV(-) Hodgkin lymphoma. Among 40 EBV(+) Hodgkin lymphoma cases and matched controls, statistically significant increased risks were associated with elevated anti-EBV VCA IgG antibody titers (relative risk = 3.1; 95% confidence interval [CI], 1.1-8.7), and an anti-EBNA-1/anti-EBNA-2 antibody ratio ≤ 1.0 versus > 1.0 (relative risk = 4.7; 95% CI, 1.6-13.8). In contrast, no significant associations were found among 88 EBV(-) Hodgkin lymphoma cases relative to their matched controls. In case-case analysis, EBV(+) disease was significantly associated with a low anti-EBNA-1/anti-EBNA-2 antibody ratio. This distinctive serologic response to EBV latent antigens, indicative of immune dysfunction in other clinical settings, is associated with an increased risk of developing EBV(+) but not EBV(-) Hodgkin lymphoma.

We show that a detector acquires a Berry phase due to its motion in spacetime. The phase is different in the inertial and accelerated case as a direct consequence of the Unruh effect. We exploit this fact to design a novel method to measure the Unruh effect. Surprisingly, the effect is detectable for accelerations 10(9) times smaller than previous proposals sustained only for times of nanoseconds.

Epstein-Barr virus (EBV) is detected in the tumor cells of some but not all Hodgkin lymphoma (HL) patients, and evidence indicates that EBV-positive and -negative HL are distinct entities. Racial/ethnic variation in EBV-positive HL in international comparisons suggests etiologic roles for environmental and genetic factors, but these studies used clinical series and evaluated EBV presence by differing protocols. Therefore, we evaluated EBV presence in the tumors of a large (n = 1,032), racially and sociodemographically diverse series of California incident classical HL cases with uniform pathology re-review and EBV detection methods. Tumor EBV-positivity was associated with Hispanic and Asian/Pacific Islander (API) but not black race/ethnicity, irrespective of demographic and clinical factors. Complex race-specific associations were observed between EBV-positive HL and age, sex, histology, stage, neighborhood socioeconomic status (SES), and birth place. In Hispanics, EBV-positive HL was associated not only with young and older age, male sex, and mixed cellularity histology, but also with foreign birth and lower SES in females, suggesting immune function responses to correlates of early childhood experience and later environmental exposures, respectively, as well as of pregnancy. For APIs, a lack of association with birth place may reflect the higher SES of API than Hispanic immigrants. In blacks, EBV-positive HL was associated with later-stage disease, consistent with racial/ethnic variation in certain cytokine polymorphisms. The racial/ethnic variation in our findings suggests that EBV-positive HL results from an intricate interplay of early- and later-life environmental, hormonal, and genetic factors leading to depressed immune function and poorly controlled EBV infection.

Few studies have examined the associations of body size and physical activity with the development of Hodgkin's lymphoma (HL) in women. In data from a population-based case-control study in women ages 19 to 79 years, we assessed the relation of self-report height, weight, body mass index (BMI), and strenuous physical activity to HL risk in 312 cases with diagnostic re-review and 325 random-digit dialed controls using logistic regression. Analyses were stratified by age group and tumor cell presence of EBV. After adjustment for social class measures, taller childhood and adult height were associated with higher HL risk. In women ages 19 to 44 years, HL risk was elevated for higher, but healthy, BMI values, whereas in women ages 45 to 79 years, associations with BMI were inverse. The odds of developing HL were lower with participation (versus nonparticipation) in strenuous physical activity in the past year [odds ratio (OR), 0.58; 95% confidence interval (95% CI), 0.39-0.87 in women 19-44 years; OR, 0.45; 95% CI, 0.19-1.06 in women 45-79 years] and throughout adult life, and with sports team membership (versus nonmembership) in high school and/or at ages 18 to 22 years. Results were similar in cases (n = 269) with and without tumor-cell EBV compared with controls, although the inverse association with physical activity was somewhat stronger for women with EBV-positive disease. These findings show that in women, body size and strenuous physical activity, both modifiable characteristics, are associated with HL risk in adult life possibly through immunologic, infectious, or genetic mechanisms.

We present a new class of solutions in odd dimensions to Einstein's equations containing either a positive or a negative cosmological constant. These solutions resemble the even-dimensional Eguchi-Hanson-(anti)-de Sitter [(A)dS] metrics, with the added feature of having Lorentzian signatures. They provide an affirmative answer to the open question as to whether or not there exist solutions with a negative cosmological constant that asymptotically approach AdS5/gamma but have less energy than AdS5/gamma. We present evidence that these solutions are the lowest-energy states within their asymptotic class.

Purpose: Epstein-Barr virus (EBV) in Hodgkin's lymphoma (HL) cells has been considered as a prognostic marker for this heterogeneous disease, but studies have yielded mixed findings, likely because of selected patient series and failure to acknowledge an effect of age on outcome. This study assessed survival after HL in a population-based cohort large enough to examine the joint effects of EBV with other factors including age, sex, and histologic subtype., Patients and Methods: Included were 922 patients with classical HL diagnosed between mid-1988 and 1997 in the Greater San Francisco Bay Area, with archived biopsy specimens assayed for EBV with immunohistochemistry and in situ hybridization. Vital status was followed through December 30, 2003 (median follow-up time, 97 months). Overall and disease-specific survival were analyzed with the Kaplan-Meier method and Cox proportional hazards regression models., Results: In children less than 15 years old, EBV presence was suggestively associated (P = .07) with favorable survival. In adults aged 15 to 44 years, EBV did not affect HL outcome, although a protective effect was suggested. In older adults (45 to 96 years), EBV presence nearly doubled the risk of overall and HL-specific mortality but only for patients with nodular sclerosis (NS) histologic subtype (hazard ratio for death = 2.5; 95% CI, 1.5 to 4.3)., Conclusion: In HL, EBV tumor cell presence is associated with better survival in young patients and poorer survival in older patients with NS, independent of other factors. Variation in outcome by age and histology could indicate biologically distinct disease entities. Evidence that EBV is a meaningful prognostic marker may have therapeutic relevance.

Two observers determine the entanglement between two free bosonic modes by each detecting one of the modes and observing the correlations between their measurements. We show that a state which is maximally entangled in an inertial frame becomes less entangled if the observers are relatively accelerated. This phenomenon, which is a consequence of the Unruh effect, shows that entanglement is an observer-dependent quantity in noninertial frames. In the high acceleration limit, our results can be applied to a nonaccelerated observer falling into a black hole while the accelerated one barely escapes. If the observer escapes with infinite acceleration, the state's distillable entanglement vanishes.

The role of Epstein-Barr virus (EBV) in Hodgkin's lymphoma (HL) etiology remains unresolved as EBV is detected in only some HL tumors and few studies have tried to reconcile its presence with factors suggesting viral etiology (e.g., childhood social class, infection history). In a population-based case-control study of San Francisco Bay area women, we analyzed interview data by tumor EBV status. Among 211 young adult cases, EBV-positive HL (11%) was associated with a single vs. shared bedroom at age 11 (OR = 4.0, 95% CI 1.1-14.4); risk was decreased for common childhood infections (OR = 0.3, 95% CI 0.1-1.0), including measles before age 10, but not with prior infectious mononucleosis (IM), which is delayed EBV infection. No study factors affected risk of young adult EBV-negative HL. Among 57 older adult cases, EBV-positive HL (23%) was unrelated to study factors; EBV-negative HL was associated with a single bedroom at age 11 (OR = 3.6, 95% CI 1.5-9.1) and IM in family members (OR = 3.1, 95% CI 1.1-9.0). Thus, delayed exposure to infection may increase risk of EBV-positive HL in young adults, but risk patterns differ in younger and older women for both EBV-positive and -negative HL. Late EBV infection does not appear relevant to risk, suggesting that other pathogens impact HL etiology in affluent female populations. Inconsistency of findings with prior studies may reflect failure of study risk factors to proxy meaningful exposures, risk differences by gender, or selection or misclassification bias. Null findings for EBV-negative HL indicate that etiologic models should be reconsidered for this common form., (Copyright 2005 Wiley-Liss, Inc.)

Background: Risk of Hodgkin's lymphoma in young adults has previously been associated with higher childhood socioeconomic status (SES) and other markers of delayed infection with common childhood pathogens, especially the Epstein-Barr virus. This study examines the current role of childhood social environment in the development of Hodgkin's lymphoma., Methods: A population-based case-control study of 565 Hodgkin's lymphoma cases and 679 controls was conducted in the Boston, MA metropolitan area and the state of Connecticut to investigate the viral etiology of Hodgkin's lymphoma., Results: A novel association was detected between attendance of nursery school or day care and reduced risk of Hodgkin's lymphoma among individuals ages 15 to 54 years. The odds ratio (95% confidence interval) for having attended preschool for at least 1 year was 0.64 (0.45-0.92). Risk of young-adult Hodgkin's lymphoma was also associated with family history of hematopoietic cancer, Jewish ethnicity, and cigarette smoking. Other indicators of childhood SES were not associated with young-adult Hodgkin's lymphoma. Among older adults ages 55 to 79 years, Hodgkin's lymphoma was associated with lower childhood SES but not with preschool attendance., Conclusions: Early exposure to other children at nursery school and day care seems to decrease the risk of Hodgkin's lymphoma in young adults, most likely by facilitating childhood exposure to common infections and promoting maturation of cellular immunity. This finding supports the delayed infection model of Hodgkin's lymphoma etiology in young adults while introducing a new major determinant of age at infection. Hodgkin's lymphoma seems to have a separate pathogenesis among older adults.

Background: Hodgkin lymphoma (HL) tumors that contain the Epstein-Barr virus (EBV) genome may differ etiologically from EBV-negative HL tumors., Methods: A case-case study examining heterogeneity of risk factors between disease subgroups compared personal characteristics and EBV antibodies between 95 EBV-positive and 303 EBV-negative patients with HL., Results: We confirmed previous associations of EBV-positive HL with older age, male sex, and mixed-cellularity (MC) histological subtypes. EBV-positive patients were less educated and more likely to have smoked cigarettes and had more prevalent and higher EBV antibody titers, compared with EBV-negative patients. After adjustment for all independent risk factors, those most strongly associated with EBV-positive HL were histological subtypes (odds ratio [OR] for MC vs. nodular sclerosis histology, 3.2; 95% confidence interval [CI], 1.4-7.2), elevated anti-viral capsid antigen level (OR, 3.1; 95% CI, 1.6-6.0), and less education (OR, 0.7; 95% CI, 0.5-1.0). Cigarette smoking and a low anti-Epstein-Barr nuclear protein (EBNA) 1 : anti-EBNA-2 ratio were also marginally associated with EBV-positive HL., Conclusions: EBV-positive HL is more common among individuals who have markers of diminished cellular immunity and an abnormal EBV antibody response. EBV appears to participate in the etiology of EBV-positive HL but may not be involved in EBV-negative HL.

The results of our study of the motion of a three particle, self-gravitating system in general relativistic lineal gravity is presented for an arbitrary ratio of the particle masses. We derive a canonical expression for the Hamiltonian of the system and discuss the numerical solution of the resulting equations of motion. This solution is compared to the corresponding nonrelativistic and post-Newtonian approximation solutions so that the dynamics of the fully relativistic system can be interpreted as a correction to the one-dimensional Newtonian self-gravitating system. We find that the structure of the phase space of each of these systems yields a large variety of interesting dynamics that can be divided into three distinct regions: annulus, pretzel, and chaotic; the first two being regions of quasiperiodicity while the latter is a region of chaos. By changing the relative masses of the three particles we find that the relative sizes of these three phase space regions changes, and that this deformation can be interpreted physically in terms of the gravitational interactions of the particles. Furthermore, we find that many of the interesting characteristics found in the case where all of the particles share the same mass also appear in our more general study. We find that there are additional regions of chaos in the unequal mass system which are not present in the equal mass case. We compare these results to those found in similar systems.

Objective: Smoking has received little consideration as a risk factor for Hodgkin lymphoma (HL) in women, despite recent significant findings in men and gender differences in HL incidence. We investigated the association of HL with lifetime cigarette smoking and household environmental tobacco smoke (ETS) exposure in women., Methods: In data from a population-based case-control study in women ages 19-79, we analyzed HL risk associated with self-reported smoking and household ETS exposure in 312 diagnostically re-reviewed cases and 325 random-digit dialing controls using logistic regression. Epstein-Barr virus (EBV) presence was determined in tumors of 269 cases., Results: In 253 cases compared to 254 controls ages 19-44, risks of HL overall, and of nodular sclerosis and EBV-negative HL, were increased 50% with ETS exposure in childhood; for 11 cases of mixed cellularity (MC) HL, current smoking and adult ETS exposure also increased risk; for 24 cases of EBV-positive HL, risk was elevated for current smoking, greater smoking intensity and duration, and ETS exposure. In 59 cases and 71 controls ages 45-79, most smoking characteristics did not appear to affect risk., Conclusions: Apparent effects of current smoking on risks of MC HL and EBV-positive HL and of household ETS on risk of all HL in young adult females may broaden the evidence implicating tobacco smoke exposures in HL etiology.

Purpose: To determine whether therapy with a DNA methyltransferase inhibitor is effective in achieving demethylation and gene re-expression in tumor DNA in patients., Methods: Biopsy specimens were obtained from patients with Epstein-Barr virus-associated tumors, enrolled on a clinical trial of 5-azacitidine, within 72 hours of the conclusion of the last infusion of the first cycle of therapy, and compared to pretreatment specimens. Methylation-specific polymerase chain reaction, bisulfite genomic sequencing, and immunohistochemistry were used to assess demethylation and gene re-expression., Results: Substantial degrees of demethylation were detected in all latent and lytic Epstein-Barr virus promoters examined. Immunohistochemistry suggested activation of a previously silent viral antigen expression in one instance., Conclusion: Pharmacologic reversal of dense CpG methylation in tumor tissue can be achieved in patients.

EBER in situ hybridization (EBER) and LMP-1 immunohistochemistry (LMP-1) are widely used for identifying Epstein-Barr virus (EBV) within tumor cells of Hodgkin lymphoma (HL), but measurement error has never been formally evaluated. To determine assay reliability, 40 HL tumors with known EBV status were stained for both EBER and LMP-1 by two laboratories and reviewed twice by four hematopathologists. Inter- and intra-observer agreement were good to excellent, with kappas above 0.78 overall and above 0.60 for most subgroup analyses. However, reliability varied by histologic subtype, preparing laboratory, reviewer and EBV status determined on consensus review. For EBER, inter-observer agreement was high for nodular sclerosis HL but somewhat lower for EBV-negative mixed cellularity HL. For LMP-1, agreement was excellent for mixed cellularity HL but somewhat less reliable for EBV-positive nodular sclerosis HL. Agreement was good for EBER and LMP-1 applied to the same specimens but differed by consensus EBV status. The variability in assay interpretation justifies caution in comparing EBV association results across HL studies and underscores the need for interpretation guidelines.

Background: Regular use of nonsteroidal anti-inflammatory drugs (NSAIDs) is associated with decreased risk of several malignancies. NSAIDs may prevent cancer development by blocking the cyclooxygenase-catalyzed synthesis of proinflammatory prostaglandins. Aspirin may also protect against Hodgkin's lymphoma by inhibiting transcription factor nuclear factor kappaB (NF-kappaB), which is necessary for immune function and the survival of Hodgkin's lymphoma cells. We examined the association between regular analgesic use and the risk of Hodgkin's lymphoma., Methods: A population-based case-control study of 565 case patients with Hodgkin's lymphoma and 679 control subjects was conducted in the metropolitan area of Boston, Massachusetts, and in the state of Connecticut. Participants reported their average use of aspirin, non-aspirin NSAIDs, and acetaminophen over the previous 5 years. Regular analgesic use was defined as consumption of at least two tablets per week on average over the preceding 5 years; non-regular use was defined as consumption of fewer than two tablets per week., Results: The risk of Hodgkin's lymphoma associated with regular aspirin use was statistically significantly lower (odds ratio [OR] = 0.60, 95% confidence interval [CI] = 0.42 to 0.85) than that associated with non-regular aspirin use. The risk was not associated with use of other non-aspirin NSAIDs (OR = 0.97, 95% CI = 0.73 to 1.30). However, the risk associated with regular acetaminophen use was statistically significantly higher (OR = 1.72, 95% CI = 1.29 to 2.31) than that associated with non-regular use., Conclusion: The inverse association between aspirin, but not other NSAIDs, and Hodgkin's lymphoma suggests that NF-kappaB signaling may play a key role in Hodgkin's lymphoma pathogenesis.

We consider the problem of three-body motion for a relativistic one-dimensional self-gravitating system. After describing the canonical decomposition of the action, we find an exact expression for the three-body Hamiltonian, implicitly determined in terms of the four coordinates and momentum degrees of freedom in the system. Nonrelativistically these degrees of freedom can be rewritten in terms of a single particle moving in a two-dimensional hexagonal well. We find the exact relativistic generalization of this potential, along with its post-Newtonian approximation. We then specialize to the equal-mass case and numerically solve the equations of motion that follow from the Hamiltonian. Working in hexagonal-well coordinates, we obtain orbits in both the hexagonal and three-body representations of the system, and plot the Poincaré sections as a function of the relativistic energy parameter eta. We find two broad categories of periodic and quasiperiodic motions that we refer to as the annulus and pretzel patterns, as well as a set of chaotic motions that appear in the region of phase space between these two types. Despite the high degree of nonlinearity in the relativistic system, we find that the global structure of its phase space remains qualitatively the same as its nonrelativistic counterpart for all values of eta that we could study. However, the relativistic system has a weaker symmetry and so its Poincare section develops an asymmetric distortion that increases with increasing eta. For the post-Newtonian system we find that it experiences a chaotic transition in the interval 0.21

In the absence of a tree-level scalar-field mass, renormalization-group methods permit the explicit summation of leading-logarithm contributions to all orders of the perturbative series within the effective potential for SU(2)xU(1) electroweak symmetry. This improvement of the effective potential function is seen to reduce residual dependence on the renormalization mass scale. The all-orders summation of leading-logarithm terms involving the dominant three couplings contributing to radiative corrections is suggestive of a potential characterized by a plausible Higgs boson mass of 216 GeV. However, the tree potential's local minimum at phi=0 is restored if QCD is sufficiently strong.

We apply a recent proposal for defining conserved mass in asymptotically de Sitter spacetimes to the class of Taub-Bolt-de Sitter spacetimes. We compute the action, entropy, and conserved mass of these spacetimes, and find that in certain instances the mass and entropy can exceed that of pure de Sitter spacetime, in violation of recent suggestive conjectures to the contrary.

Background: Epidemiologic characteristics of human immunodeficiency virus (HIV)-related Hodgkin lymphoma (HL) have not been examined in the Greater San Francisco Bay Area, a center of the HIV/acquired immunodeficiency syndrome (AIDS) epidemic, for a decade, despite changes in AIDS-associated diseases after the availability of highly active antiretroviral therapies (HAART)., Methods: With population-based cancer registry data for 1988-1998, the authors examined risk factors, Epstein-Barr virus (EBV) association, incidence rates, and survival probabilities for 1752 patients with HL who were classified as HIV-positive or HIV-negative by a cancer registry-based method., Results: One hundred twenty-eight patients with HL (7%) were classified with HIV/AIDS; 95% were male. Among males, multivariate analysis (n=514 patients) found that HIV-related HL was associated strongly at diagnosis with ages 30-49 years, San Francisco residence, late-stage disease, lymphocyte depletion and unspecified histologic subtypes, and tumor cell EBV but not with other clinical features or mixed cellularity histology. Survival among patients with HIV-related HL, although it was poor, did not differ by race/ethnicity but was worse for patients with the nonnodular sclerosis histologic subtypes. Patients who were HIV-positive with HAART era (1996-1998) diagnoses were slightly older, were less likely to live in San Francisco, and were much more likely to be Hispanic compared with HIV-positive patients who were diagnosed before the HAART era; they had somewhat less aggressive disease and better survival. Incidence rates were higher for patients with HL overall compared with patients who had HIV-unrelated HL by 11% for white patients, 22% for black patients, and by 14% for Hispanic patients; excesses were greater in young adults., Conclusions: Among males in the San Francisco Bay Area, HIV-related HL had distinctive demographic features, more aggressive clinical characteristics, stronger EBV association, and poorer survival and contributed to elevated regional HL incidence rates, particularly in young adults. Patients with HIV-related HL who were diagnosed after HAART was introduced appeared to have less aggressive disease and better survival., (Copyright 2003 American Cancer Society.)

We consider the 3-body problem in relativistic lineal [i.e., (1+1)-dimensional] gravity and obtain an exact expression for its Hamiltonian and equations of motion. While general-relativistic effects yield more tightly bound orbits of higher frequency compared to their nonrelativistic counterparts, as energy increases we find in the equal-mass case no evidence for either global chaos or a breakdown from regular to chaotic motion, despite the high degree of nonlinearity in the system. We find numerical evidence for mild chaos and a countably infinite class of nonchaotic orbits, yielding a fractal structure in the outer regions of the Poincaré plot.

The Lyme disease spirochete, Borrelia burgdorferi Johnson, Schmidt, Hyde, Steigerwalt, and Brenner was discovered in blacklegged ticks, Ixodes scapularis Say at Rondeau Provincial Park, Ontario, Canada During this 2-yr study, spirochetes were found in B. burgdorferi-positive I. scapularis larvae attached to B. burgdorferi-infected white-footed mice, Peromyscus leucopus Rafinesque. Isolates of B. burgdorferi were cultured from blacklegged tick adults, and confirmed positive with polymerase chain reaction by targeting OspA and rrf (5S)-rrl (23S) genes. These findings show an endemic area for B. burgdorferi within an established population of L. scapularis at Rondeau Provincial Park.

Histochemical stains demonstrate Epstein-Barr virus (EBV) in approximately 40% of all Hodgkin hymphomas, suggesting a role in tumorigenesis and the potentialfor EBV-targeted therapy. As research progresses, it is important to define criteria for interpreting histochemical stains. Four hematopathologists independently interpreted EBV-encoded RNA (EBER) and latent membrane protein 1 (LMP1) histochemical stains from 40 cases of Hodgkin lymphoma and then reviewed the stains as a group to resolve discrepancies and to develop interpretation guidelines. To call a Hodgkin case EBV-related, the EBER and/or LMP1 signal must be unequivocally present in Reed-Sternberg/Hodgkin (RS/H) cells. The cytologic features and distribution of stained cells should be matched with those on the corresponding H&E-stained slide to help interpret whether the EBER or LMP1 signal is in malignant or reactive cells. The EBER signal is localized to the nucleus, whereas LMP1 is in the cytoplasm and surface membrane. In some cases, only a fraction of RS/H cells express these factors for technical or biologic reasons. Before calling a case EBER-negative, it is essential to show that tumor cell RNA is preserved and available for hybridization. LMP1 staining, although usually strong among all tumor cells in a given case, may alternatively be focal and weak, contributing to false-negative interpretation. EBER and LMP1 assays in combination are more effective than either assay alone for identifying EBV-related Hodgkin lymphoma.

We consider the statistical mechanics of a general relativistic one-dimensional self-gravitating system. The system consists of N particles coupled to lineal gravity and can be considered as a model of N relativistically interacting sheets of uniform mass. The partition function and one-particle distribution functions are computed to leading order in 1/c where c is the speed of light; as c --> infinity results for the nonrelativistic one-dimensional self-gravitating system are recovered. We find that relativistic effects generally cause both position and momentum distribution functions to become more sharply peaked, and that the temperature of a relativistic gas is smaller than its nonrelativistic counterpart at the same fixed energy. We consider the large-N limit of our results and compare this to the nonrelativistic case.

Purpose: To evaluate the long-term outcome after allogeneic (allo) and autologous (auto) blood or marrow transplantation (BMT) in patients with relapsed or refractory Hodgkin's lymphoma (HL)., Patients and Methods: We analyzed the outcome of 157 consecutive patients with relapsed or refractory HL, who underwent BMT between March 1985 and April 1998. Patients

A total of 152 ixodid ticks (Acari: Ixodidae) consisting of nine species was collected from 82 passerine birds (33 species) in 14 locations in Canada from 1996 to 2000. The Lyme disease spirochete Borrelia burgdorferi Johnson, Schmidt, Hyde, Steigerwaldt & Brenner was cultured from the nymph of a blacklegged tick, Ixodes scapularis Say, that had been removed from a common yellowthroat, Geothlypis trichas L., from Bon Portage Island, Nova Scotia. As a result of bird movement, a nymphal I. scapularis removed from a Swainson's thrush, Catharus ustulatus incanus (Godfrey), at Slave Lake, Alberta, during spring migration becomes the new, most western and northern record of this tick species in Canada. Amblyomma longirostre Koch, Amblyomma sabanerae Stoll, and Ixodes baergi Cooley & Kohls are reported for the first time in Canada. Similarly, Amblyomma americanum L., Arnblyomma maculatum Koch, and ixodes muris Bishopp & Smith are reported for the first time on birds in Canada. After removal of an I. muris gravid female from a song sparrow, Melospiza melodia Wilson, at St. Andrews, New Brunswick, eggs were laid, which developed into larvae, and this new tick-host record demonstrates that birds have the potential to start a new tick population. We conclude that passerine birds disperse several species of ixodid ticks in Canada, and during spring migration translocate ticks from the United States, and Central and South America, some of which are infected with B. burgdorferi.

The cases of two patients with Stage IE primary cutaneous T-cell-rich B-cell lymphoma (TCRBCL) are described. In both, the lesion showed a dense infiltrate by numerous small T lymphocytes with scattered histiocytes and large atypical B-lymphoid cells. Polymerase chain reaction assays demonstrated that the B cells were monoclonal, with immunoglobulin heavy-chain gene rearrangement. No clonal rearrangements of the T-cell receptor gamma gene were observed. Both patients were disease-free at 4 months and at 5 years after therapy, respectively. Although rare, primary cutaneous T-cell-rich B-cell lymphoma appears to have a better prognosis than its nodal counterpart, with or without skin involvement.