406 results on '"Cohen, Bruce"'
Search Results
2. Fetal anomaly diagnosis and termination of pregnancy.
- Author
-
Graf, William D., Cohen, Bruce H., Kalsner, Louisa, Pearl, Phillip L., Sarnat, Harvey B., and Epstein, Leon G.
- Subjects
- *
FETAL abnormalities , *ABORTION , *MEDICAL ethics , *ETHICAL problems , *CODES of ethics - Abstract
The aim of this review was to discuss bioethics in prenatal diagnosis and health care after recent legislative and judicial changes affecting reproductive rights, such as the repeal of 'Roe v. Wade' in the United States. We recognize that abortion involves particular moralities that are not universal or shared by all cultures, groups, and individuals. We reviewed the historical aspects of embryology and personhood, fetal morbidity and mortality, and parental options for prenatal diagnostic testing. We examined relevant ethical issues including informed consent, the emergence of fetal pain, reproductive autonomy, the fiduciary responsibilities of pregnant mothers, and the obligations of physicians caring for the maternal–fetal dyad. The code of medical ethics includes respect for decisional privacy and the protection of information shared in confidence. When a fetal anomaly is diagnosed, pregnant mothers must be informed about the risks, burdens, and alternatives in either continuing or terminating the pregnancy. Parental choice should include the right to refuse testing, the informed choice not to know about certain genetic test results, and the right to make informed decisions about the best interests of the future child. In the diagnosis and care of fetal anomalies, moral dilemmas arise. Before fetal viability, the mother's autonomy, sense of beneficence, and personal values should be trusted and respected. Perinatal palliative care should be available to pregnant mothers whose anomalous fetus is carried to birth. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
3. The 'feminisation' of psychiatric discourse: A Marxist analysis of women's roles in neoliberal society.
- Author
-
Cohen, Bruce MZ and Hartmann, Rearna
- Subjects
- *
WOMEN'S roles , *MARXIST analysis , *SOCIAL control , *DISCOURSE analysis , *GENDER role , *PREMENSTRUAL syndrome - Abstract
In analysing the increasing rates of female 'mental illness' in neoliberal society, this article draws on Marxist and feminist theory to conceptualise psychiatry as an institution of patriarchal and capitalist power, responsible for reinforcing traditional gender roles. Through outlining the changing circumstances of women, including the recent 'feminisation' of the labour force, we argue that there has been a more acute need for patriarchal capitalism to curtail the emancipatory potential of women through the heightened enforcement of sex-role ideology. This is demonstrated through a profile of 'feminised' mental disorders which have appeared in the Diagnostic and Statistical Manual of Mental Disorders (DSM) since 1980 – including premenstrual dysphoric disorder and female sexual interest/arousal disorder – which we argue purposely reproduce a discourse which restricts women's advancements in paid employment while reinforcing the cliché of 'respectable femininity' as still primarily associated with the family and the home. We conclude the article by suggesting that, under the conditions of neoliberalism, the mental health system is becoming an increasingly powerful institution for the social control of gender. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
4. Occupational Experience Effects on Physiological and Perceptual Responses of Common Soldiering Tasks.
- Author
-
Cohen, Bruce S., Redmond, Jan E., Haven, Caitlin C., Foulis, Stephen A., Canino, Maria C., Frykman, Peter N., and Sharp, Marilyn A.
- Subjects
- *
PHYSIOLOGICAL stress , *WORK , *OXYGEN consumption , *JOB stress , *TASK performance , *REGRESSION analysis , *PHYSICAL fitness , *SIMULATION methods in education , *COMPARATIVE studies , *MILITARY service , *EXPERIENTIAL learning , *HEART beat , *EXERCISE , *DESCRIPTIVE statistics , *EMPLOYEES' workload , *MILITARY personnel - Abstract
Supplemental Digital Content is Available in the Text. Cohen BS, Redmond JE, Haven CC, Foulis SA, Canino MC, Frykman PN, Sharp MA. Occupational Experience Effects on Physiological and Perceptual Responses of Common Soldiering Tasks. J Strength Cond Res 37(4): 894–901, 2023—This study measured the impact of occupational experience (i.e., time spent deployed, in military service, and in job and task performance frequency in training, deployment, and study practice) on the physiological (heart rate [HR] and oxygen consumption [VO2]) and perceptual (rate of perceived exertion [RPE]) responses to performance of critical physically demanding tasks (CPDTs). Five CPDTs (road march, build a fighting position, move under fire, evacuate a casualty, and drag a casualty to safety), common to all soldiers, were performed by 237 active duty soldiers. Linear regression models examined the association between measures of experience and physiological and perceptual performance responses to task demands. The level of significance was adjusted for multiple comparisons and set at ρ ≤ 0.0125 for this study. Significant and notable effect sizes included the impact of time spent deployed on the physiological measures of the road march (PostHR F = 24.84, p < 0.0001, β=-9.65), sandbag fill (PostHR F = 8.26, p = 0.005, β = −2.83), and sandbag carry (MeanHR F = 7.51, p = 0.007, β = −1.12; PostHR F = 7.35, p = 0.007, β = −0.87). For the road march task, there was a nearly 10 bpm decrease in postperformance HR for every year spent deployed. Road march, sandbag fill, and sandbag carry tasks PostHRs were also notably negatively associated with the experience measures of time in their MOS (job and time in military service but not for other physiological and perceptual responses, including VO2 and RPE. Frequency of task performance in training, deployment, and study practice was not meaningfully associated with experience. The results suggest that increasing task familiarization through on-the-job occupational operational experience may result in greater proficiency and reduced physiological effort. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
5. Clinical phenotypes of five patients with psychotic disorders carrying rare schizophrenia-associated loss-of-function variants.
- Author
-
Cohen, Bruce M., Singh, Tarjinder, Öngür, Dost, Konstantin, Grace E., and Gardner, Margaret E.
- Subjects
- *
PSYCHOSES , *ATTEMPTED suicide , *PHENOTYPES , *MENTAL illness , *CLOZAPINE , *PERINATAL mood & anxiety disorders - Abstract
The Schizophrenia Exome Meta-Analysis (SCHEMA) consortium identified 10 genes in which loss-of-function (LoF) variants are highly associated with schizophrenia (SZ). In a well-characterized sample of 988 patients with psychotic disorders, we investigated whether patients bearing a SCHEMA variant presented with unusual or unique signs, symptoms, or course of illness. We identified 5 patients who carried a LoF variant in a SCHEMA gene, each in a different gene. None of the patients with a SCHEMA variant had unique symptoms. However, compared to the average of patients in the sample, all of the patients with a SCHEMA variant had earlier onset of any mental illness and more hospitalizations. Also, among SCHEMA carriers, 80 % were treated with clozapine, 60 % with ECT, all with either clozapine or ECT and 40 % with both clozapine and ECT, compared to only 2 % treated with clozapine and 18 % treated with ECT in the comparison group of patients without SCHEMA variants. All 5 patients with a SCHEMA variant had polysubstance abuse, and all had attempted suicide. Fewer than half had such presentations in the group without SCHEMA variants. In this small sample, SCHEMA variants appear to be associated with earlier onset, less favorable response to standard first-line treatments, and more severe illness, but not unique presentations of illness. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
6. Physical Injuries, Treatment-Seeking, and Perceived Barriers to Treatment in U.S. Army Drill Sergeants.
- Author
-
Elliman, Toby D, Cohen, Bruce S, Heaton, Kristin J, and Proctor, Susan P
- Subjects
- *
SLEEP , *HEALTH behavior , *SLEEP deprivation , *RESEARCH funding , *MILITARY personnel - Abstract
Introduction: Drill sergeants work under mentally and physically challenging conditions. The current study examined self-reported rates of physical injuries in drill sergeants; rates of treatment-seeking for injuries; perceived barriers toward treatment-seeking; and associated demographic and environmental factors.Materials and Methods: Drill sergeants from across all Army basic training locations completed self-report surveys from September to November of 2018. In total, 726 drill sergeants were included in analyses. Drill sergeants indicated whether they had acquired an injury during their time in the drill sergeant role and whether they had sought treatment for all such injuries. Furthermore, drill sergeants rated their agreement with a number of possible perceived barriers to treatment-seeking for physical injuries. Regression models examining each phenomenon included hours of sleep obtained per day; general- and health-specific leadership behaviors of the company command teams; unit cohesion; time as a drill sergeant; duty location; gender; military operational specialty; years in the military; previous combat deployments; and route of assignment. The study was approved by the Walter Reed Army Institute of Research Institutional Review Board.Results: In total, 38% of respondents reported acquiring an injury during their time as drill sergeants. Of those who had acquired an injury, 61% reported seeking medical help for all injuries acquired. Injuries were more likely in females (49%) than in males (34%) and less likely in drill sergeants reporting at least 6 hours of sleep (27%) versus those reporting 5 hours (40%) and 4 hours or less (43%). Reported comparisons were significant after controlling for demographic and environmental variables in regression models. The most strongly endorsed perceived barriers to treatment-seeking were "Seeking help would place too much burden on the other drill sergeants" (69%) and "Seeking help would interfere with my ability to train the recruits" (60%). Both of these perceived barriers were significantly associated with reduced treatment-seeking in injured drill sergeants, after controlling for demographic and environmental variables.Conclusions: This study is the first to examine injury occurrence, treatment-seeking, and perceived barriers to treatment-seeking in U.S. Army drill sergeants. Building on previous studies that showed the negative effects of sleep deprivation on the safety and behavioral health of drill sergeants, the current study gives further evidence of the negative effects of such sleep deprivation, this time in the domain of physical injuries. The results suggest that pursuing strategies that allow for healthier sleep duration may contribute to injury reduction. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
- View/download PDF
7. Diagnostic terms psychiatrists prefer to use for common psychotic and personality disorders.
- Author
-
Cohen, Bruce M., Öngür, Dost, Babb, Suzann M., and Harris, Peter Q.
- Subjects
- *
PERSONALITY disorders , *PSYCHOSES , *ANTISOCIAL personality disorders , *PSYCHIATRISTS , *NARCISSISTIC personality disorder , *MEDICAL personnel - Abstract
There are ongoing discussions on updating various standard psychiatric terms, including schizophrenia, which can be confusing, and personality disorders, which can be pejorative. To contribute to this process, suggestions and recommendations on terminology were sought from academic psychiatrists with substantial clinical experience. In an online survey, 263 psychiatrists were asked how often they used alternative instead of standard terms for the diagnosis or symptom description of psychotic disorders and DSM Cluster B personality disorders. They were also asked what specific terms they preferred to use. Reasons for their views and choices were obtained. 125 clinicians (48%) responded. Only a minority of clinicians (31%) tended to use the term schizophrenia often, preferring to say psychosis or to refer to thinking and perceptual problems. Even lower proportions of clinicians (7–14%) often use the terms for Cluster B personality disorder subtypes: antisocial, narcissistic, histrionic, and borderline. Alternatives suggested for these disorders included discussing emotional dysregulation, traits of sensitivity and reactivity, and relational difficulties. Reasons cited for choosing alternative terms were to avoid miscommunication (71% of responders) and to avoid offending the patient (78% of responders). There are practical alternatives to standard psychiatric terminology that may improve communication with patients and be more respectful choices, as well. The suggestions of the psychiatrists responding to this survey might be of immediate value to others in their practices and might be worthy of consideration by those writing the next versions of the standard manuals, both the DSM and the ICD. • Some psychiatric terms, such as schizophrenia, communicate poorly; others, for some personality disorders, are pejorative. • A survey on these terms was sent to 263 psychiatrists who practice and teach in academic settings. • Most responders (69%) preferred not to use schizophrenia; very few (<14%) used terms for DSM Cluster B personality disorders. • Alternative terms clinicians preferred might be useful to other practitioners and worth considering in standard diagnosis. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
8. Effects of Sleep Restriction on Soldiers' Psychological Flow State and Marksmanship Performance.
- Author
-
Cohen, Bruce S., Merullo, Donna J., Smith, Carl D., Cooper, Adam D., and Smith, Tracey
- Subjects
- *
STATISTICS , *ANALYSIS of variance , *FIREARMS , *TASK performance , *WEAPONS , *PEARSON correlation (Statistics) , *SLEEP deprivation , *DECISION making , *PSYCHOLOGY of military personnel , *JOB performance , *REACTION time , *DATA analysis software , *DATA analysis - Abstract
Marksmanship performance is a challenging skill for recreational enthusiasts, sport competitors and tactical (military and law enforcement) athletes. Peak performance is associated with the favorable psychological state of 'flow,' occurring when we perceive equilibrium between challenges and our capabilities. Stressors, like sleep loss, disrupt marksmanship performance and may also degrade the experience of flow. We examined the effects of sleep restriction on flow state and marksmanship performance. U.S. Army Soldiers (n=15, Mean age=21.2 years, SD=3.5) conducted a rifle marksmanship task on a simulator followed by the Long Flow State Scale 2 -- Physical (FSS-2). Four sessions were conducted including a well-rested baseline session on the first day of the study, and then again at 20, 44 and 68 hr into sleep restriction. Overall flow summary score and five subscale components of flow degraded significantly by 44 hr of sleep restriction. The longer the duration of weapon firing each day, the greater the decline in flow. Lower overall flow scores were associated with slower trigger pull (Pearson r(13) = -.59, p = .02) and slower general reaction time (r(13) = -.64, p =< .01), with significant degradation at 68 hr of sleep restriction. Higher overall flow state scores positively correlated with the ability to correctly identify enemy from friendly targets at 68 hr (r(13) = 0.53, p = .04). Our data suggest that marksmen whose flow is less disrupted by sleep restriction may also perform more timely and with less errors in decision making. [ABSTRACT FROM AUTHOR]
- Published
- 2022
9. Alternative Diagnostic Models of the Psychotic Disorders: Evidence-Based Choices.
- Author
-
Cohen, Bruce M., Öngür, Dost, and Babb, Suzann M.
- Subjects
- *
PSYCHOSES , *SYMPTOMS , *DIAGNOSIS , *GENETICS , *FACTOR structure - Abstract
Standard diagnostic systems, the predominantly categorical DSM-5 and ICD-11, have limitations in validity, utility, and predictive and descriptive power. For psychotic disorders, these issues were partly addressed in current versions, but additional modifications are thought to be needed. Changes should be evidence based. We reviewed categorical, modified-categorical, and continuum-based models versus factor-based models of psychosis. Factors are clusters of symptoms or single prominent aspects of illness. Consistent evidence from studies of the genetics, pathobiology, and clinical presentation of psychotic disorders all support an underlying structure of factors, not categories, as best characterizing psychoses. Factors are not only the best fit but also comprehensive, as they can encompass any key feature of illness, including symptoms and course, as well as determinants of risk or response. Factors are inherently dimensional, even multidimensional, as are the psychoses themselves, and they provide the detail needed for either grouping or distinguishing patients for treatment decisions. The tools for making factor-based diagnoses are available, reliable, and concordant with actual practices used for clinical assessments. If needed, factors can be employed to create categories similar to those in current use. In addition, they can be used to define unique groupings of patients relevant to specific treatments or studies of the psychoses. Lastly, factor-based classifications are concordant with other comprehensive approaches to psychiatric nosology, including personalized (precision treatment) models and hierarchical models, both of which are currently being explored. Factors might be considered as the right primary structural choice for future versions of standard diagnostic systems, both DSM and ICD. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
10. A novel exercise testing algorithm to diagnose mitochondrial myopathy.
- Author
-
Bhatia, Rajeev, Cohen, Bruce H., and McNinch, Neil
- Abstract
Introduction: Oxygen uptake efficiency slope (OUES) is a noninvasive cardiopulmonary exercise testing (CPET) measurement based on oxygen uptake (V˙O2) and minute ventilation (V˙E) and is a marker of the efficiency of oxygen utilization by the body. However, it has not been studied in mitochondrial disorders. We explored noninvasive CPET parameters, including OUES, as a way to reliably diagnose mitochondrial myopathy. Methods: We performed cycle ergometer maximal exercise testing on definite and suspected mitochondrial myopathy subjects (MM‐D and MM‐S) and their age‐ and sex‐matched controls. OUES was corrected for body surface area (OUES/BSA) to eliminate the effect of body size. Results: A total of 40 participants, including 20 MM‐D (n = 13; 6 males; aged 14‐64 years) and 7 MM‐S (5 males, aged 11‐30 years) subjects and 20 controls, completed the study. MM‐D subjects showed lower aerobic fitness than controls. OUES/BSA was lower in MM‐D subjects, suggesting inefficient oxygen utilization. Area under the curve (AUC) and 95% confidence interval (CI) for OUES/BSA (AUC, 0.91; 95% CI, 0.80‐1.00), peak V˙O2 percent predicted (AUC, 0.95; 95% CI, 0.86‐1.00), and V˙O2/work slope (AUC, 0.94; 95% CI, 0.85‐1.00) showed excellent ability to diagnose mitochondrial myopathy in MM‐D subjects. We applied a diagnostic approach based on the parameters just noted to MM‐S subjects and their controls and were able to support or disprove the diagnosis of mitochondrial myopathy. Discussion: We proposed and applied an approach based on the aformentioned three CPET parameters to diagnose mitochondrial myopathy reliably and found it to be clinically useful. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
11. Know What I Mean.
- Author
-
Cohen, Bruce
- Subjects
- KNOW What I Mean (Poem), COHEN, Bruce
- Abstract
Thew poem "Know What I Mean" represented by Bruce Cohen. First Line: "You once pointed at the braided purple garlic in an open-air market" Last Line: "if you tried to translate the"
- Published
- 2023
12. Well‐Being in the Nation: A Living Library of Measures to Drive Multi‐Sector Population Health Improvement and Address Social Determinants.
- Author
-
SAHA, SOMAVA, COHEN, BRUCE B., NAGY, JULIA, McPHERSON, MARIANNE E., and PHILLIPS, ROBERT
- Subjects
- *
COMMUNITIES , *DELPHI method , *HEALTH , *HEALTH services accessibility , *HEALTH status indicators , *INTERPROFESSIONAL relations , *LIFE expectancy , *MENTAL health , *POVERTY , *RESEARCH funding , *GROUP process , *POPULATION health , *HEALTH & social status , *COVID-19 - Abstract
Policy PointsWell‐being In the Nation (WIN) offers the first parsimonious set of vetted common measures to improve population health and social determinants across sectors at local, state, and national levels and is driven by what communities need to improve health, well‐being, and equity.The WIN measures were codesigned with more than 100 communities, federal agencies, and national organizations across sectors, in alignment with the National Committee on Vital and Health Statistics, the Foundations for Evidence‐Based Policymaking Act, and Healthy People 2030. WIN offers a process for a collaborative learning measurement system to drive a learning health and well‐being system across sectors at the community, state, and national levels.The WIN development process identified critical gaps and opportunities in equitable community‐level data infrastructure, interoperability, and protections that could be used to inform the Federal Data Strategy. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
13. Sphingosine 1‐phosphate receptor modulators in multiple sclerosis treatment: A practical review.
- Author
-
Coyle, Patricia K., Freedman, Mark S., Cohen, Bruce A., Cree, Bruce A. C., and Markowitz, Clyde E.
- Subjects
- *
MULTIPLE sclerosis , *SPHINGOSINE , *DRUG monitoring , *MACULAR edema , *PATIENT monitoring - Abstract
Four sphingosine 1‐phosphate (S1P) receptor modulators (fingolimod, ozanimod, ponesimod, and siponimod) are approved by the US Food and Drug Administration for the treatment of multiple sclerosis. This review summarizes efficacy and safety data on these S1P receptor modulators, with an emphasis on similarities and differences. Efficacy data from the pivotal clinical trials are generally similar for the four agents. However, because no head‐to‐head clinical studies were conducted, direct efficacy comparisons cannot be made. Based on the adverse event profile of S1P receptor modulators, continued and regular monitoring of patients during treatment will be instructive. Notably, the authors recommend paying attention to the cardiac monitoring guidelines for these drugs, and when indicated screening for macular edema and cutaneous malignancies before starting treatment. To obtain the best outcome, clinicians should choose the drug based on disease type, history, and concomitant medications for each patient. Real‐world data should help to determine whether there are meaningful differences in efficacy or side effects between these agents. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
14. Young people's voices on emotions: a narrative inquiry.
- Author
-
McLeay, Roberto, Powell, Darren, and Cohen, Bruce M. Z.
- Subjects
- *
MENTAL health of youth , *NARRATIVES , *PRIMARY schools , *EMOTIONS , *WELL-being - Abstract
This article presents an innovative narrative inquiry study carried out in a primary school in Aotearoa New Zealand with three young people who provide insights into how they perceive, construct, give meaning to, and make sense of their own emotions. The analysis from this primary research draws on Foucauldian scholarship to examine how the narratives that young people construct about their feelings are shaped by dominant psy-discourses on emotions. We argue that through these discourses, certain voices of authority, knowledge, and ways of seeing are privileged in schools—while others are silenced—in order to label young people as emotionally or mentally "unwell" and in need of expert assistance. In doing so, we suggest that critical interdisciplinary work by health, psychology, counselling, and education professionals in schools can create spaces to explore inter-professional dialogue and reflexivity, as well as to challenge orthodox approaches to young people's emotional lives. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
15. A single TRPV1 amino acid controls species sensitivity to capsaicin.
- Author
-
Chu, Ying, Cohen, Bruce E., and Chuang, Huai-hu
- Subjects
- *
TRP channels , *SENSORY neurons , *CAPSAICIN , *CHIMERISM , *TRPV cation channels - Abstract
Chili peppers produce capsaicin (a vanilloid) that activates the transient receptor potential cation channel subfamily V member 1 (TRPV1) on sensory neurons to alter their membrane potential and induce pain. To identify residues responsible for differential TRPV1 capsaicin sensitivity among species, we used intracellular Ca2+ imaging to characterize chimeras composed of capsaicin-sensitive rat TRPV1 (rTRPV1) and capsaicin-insensitive chicken TRPV1 (cTRPV1) exposed to a series of capsaicinoids. We found that chimeras containing rat E570-V686 swapped into chicken receptors displayed capsaicin sensitivity, and that simply changing the alanine at position 578 in the S4-S5 helix of the chicken receptor to a glutamic acid was sufficient to endow it with capsaicin sensitivity in the micromolar range. Moreover, introduction of lysine, glutamine or proline at residue A578 also elicited capsaicin sensitivity in cTRPV1. Similarly, replacing corresponding rTRPV1 residue E570 with lysine or glutamine retained capsaicin sensitivity. The hydrophilic capsaicin analog Cap-EA activated a cTRPV1-A578E mutant, suggesting that A578 may participate in vanilloid binding. The hydrophilic vanilloid agonist zingerone did not activate any A578 mutants with capsaicin sensitivity, suggesting that the vanilloid group alone is not sufficient for receptor activation. Our study demonstrates that a subtle modification of TRPV1 in different species globally alters capsaicin responses. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
16. Perspectives on Research in Computational Plasma Physics With Applications to Experiments.
- Author
-
Cohen, Bruce I.
- Subjects
- *
COMPUTATIONAL physics , *PLASMA physics , *PHYSICS experiments , *NONLINEAR differential equations , *PARTIAL differential equations - Abstract
Computational plasma physics was born some 50 years ago with the development of high-speed computers. Computer simulation is well suited to the challenging nature of fundamental and applied plasma science, which exhibits enormous ranges of time and space scales, and whose underlying mathematical framework is comprised of nonlinear partial differential equations and nonlinear kinetic equations. Computational plasma physics has advanced from relatively simple calculations with limited dimensionality and scope to sophisticated and comprehensive simulation models. Moreover, computational plasma physics has matured as a significant scientific discipline with a rigorous mathematical foundation and voluminous literature. While computational plasma physics has greatly benefitted from the growth in computing capability by many orders of magnitude, the contributions from innovation in methods and algorithms have been no less important. This talk presents a personal perspective on the development and application of computational plasma physics to plasmas in nature and in the laboratory. The examples described will be based on experience over the course of a career in computational plasma physics and illustrate both the fundamental plasma phenomena and the behavior of laboratory plasmas. Some of the specific examples include simulations of microinstabilities in the magnetic mirror, tokamak and spheromak plasmas, laser–plasma interactions, and the Knudsen-layer phenomena, as it affects fusion performance. The examples also illustrate the development of appropriate models and algorithms that are well suited to simulating the phenomena of interest efficiently. A particular interest of the author has been the development of multiple time-scale algorithms. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
17. Prenatal Diagnosis of a Furcate Placenta.
- Author
-
Cohen, Bruce, Wilson, Monika, Cohen, Austin, and Yum, Mimi
- Subjects
- *
THIRD trimester of pregnancy , *UMBILICAL cord , *DIFFERENTIAL diagnosis , *LABOR complications (Obstetrics) , *FETAL ultrasonic imaging - Abstract
Background: A furcate placental cord insertion is rare and potentially dangerous. Prenatal diagnosis of this finding has been reported on only two prior occasions.Case: We present the case of a 33-year-old patient who, at 35 weeks of gestation, was suspected on ultrasonography to have a cord insertion that was both furcate and velamentous. Because of this finding, the patient underwent labor induction at 37 weeks of gestation and delivered a vigorous neonate vaginally. Pathologic evaluation confirmed furcate placenta.Conclusion: The identification of a furcate placenta, a potentially lethal umbilical cord insertion site abnormality, is possible prenatally. Future research should elucidate the prevalence of furcate cord insertions as well as whether they impose increased fetal risk. [ABSTRACT FROM AUTHOR]- Published
- 2020
- Full Text
- View/download PDF
18. Relationship of Anthropometric Measures on Female Trainees' and Active Duty Soldiers' Performance of Common Soldiering Tasks.
- Author
-
Redmond, Jan E, Cohen, Bruce S, Haven, Caitlin C, Pierce, Joseph R, Foulis, Stephen A, Frykman, Peter N, Canino, Maria C, and Sharp, Marilyn A
- Subjects
- *
BODY mass index , *MILITARY personnel , *TASK performance , *ANTHROPOMETRY - Abstract
Introduction: This study compared the relationship between height (HT), body mass (BM), and body mass index (BMI) of female trainees and active duty female soldiers and their performance on simulated common soldiering tasks (CSTs) with high physical demands.Methods: Female trainees (n = 133) and soldiers (n = 229) completed the following CSTs: sandbag carry, move under fire, casualty drag, casualty evacuation, and road march. Quartiles were created among HT, BM, and BMI by which task performance was compared using ANOVAs with Tukey post hoc comparisons.Results: For both trainees and soldiers, HT, BM, and BMI were positively associated with improved road march, casualty drag, casualty evacuation, and sandbag carry performance. On the move under fire task, only soldier HT was positively associated with improved performance.Conclusion: Female trainees and soldiers who are taller and heavier with a higher BMI may demonstrate better performance on CSTs required of all soldiers. In addition to task-specific training, performance of CSTs may be enhanced in tasks requiring strength and power by recruiting and retaining taller and heavier females with a higher BMIs. Allowances should be considered for soldiers and trainees who can successfully perform soldiering tasks with high physical demands despite less desirable anthropometric measurements. [ABSTRACT FROM AUTHOR]- Published
- 2020
- Full Text
- View/download PDF
19. Theoretical plasma physics.
- Author
-
Kaufman, Allan N. and Cohen, Bruce I.
- Subjects
- *
PLASMA physics , *COLLISIONLESS plasmas , *PLASMA diffusion , *VLASOV equation , *LANDAU damping , *COLLISIONAL plasma , *SLIDING friction - Abstract
These lecture notes were presented by Allan N. Kaufman in his graduate plasma theory course and a follow-on special topics course (Physics 242A, B, C and Physics 250 at the University of California Berkeley). The notes follow the order of the lectures. The equations and derivations are as Kaufman presented, but the text is a reconstruction of Kaufman's discussion and commentary. The notes were transcribed by Bruce I. Cohen in 1971 and 1972, and word processed, edited and illustrations added by Cohen in 2017 and 2018. The series of lectures is divided into four major parts: (i) collisionless Vlasov plasmas (linear theory of waves and instabilities with and without an applied magnetic field, Vlasov–Poisson and Vlasov–Maxwell systems, Wentzel–Kramers–Brillouin–Jeffreys (WKBJ) eikonal theory of wave propagation); (ii) nonlinear Vlasov plasmas and miscellaneous topics (the plasma dispersion function, singular solutions of the Vlasov–Poisson system, pulse-response solutions for initial-value problems, Gardner's stability theorem, gyroresonant effects, nonlinear waves, particle trapping in waves, quasilinear theory, nonlinear three-wave interactions); (iii) plasma collisional and discreteness phenomena (test-particle theory of dynamic friction and wave emission, classical resistivity, extension of test-particle theory to many-particle phenomena and the derivation of the Boltzmann and Lenard–Balescu equations, the Fokker–Planck collision operator, a general scattering theory, nonlinear Landau damping, radiation transport and Dupree's theory of clumps); (iv) non-uniform plasmas (adiabatic invariance, guiding-centre drifts, hydromagnetic theory, introduction to drift-wave stability theory). [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
20. Pulling Baby Teeth.
- Author
-
Cohen, Bruce
- Subjects
- PULLING Baby Teeth (Poem), COHEN, Bruce
- Abstract
The poem "Pulling Baby Teeth" by Bruce Cohen is presented. First Line: As portrayed in comics, a string knotted to a doorknob or resorting to needle-Last Line: & wake disoriented, mouthing the nickname of a boy who no longer lives here.
- Published
- 2022
21. Surveyed Reasons for Not Seeking Medical Care Regarding Musculoskeletal Injury Symptoms in US Army Trainees.
- Author
-
Cohen, Bruce S, Pacheco, Brooke M, Foulis, Stephen A, Canino, Maria C, Redmond, Jan E, Westrick, Richard B, Hauret, Keith G, and Sharp, Marilyn A
- Subjects
- *
MEDICAL care , *MUSCULOSKELETAL system injuries , *MILITARY readiness , *MEDICAL care costs , *COMMAND of troops , *ARMIES - Abstract
Introduction: Musculoskeletal injuries (MSKIs) pose a significant threat to military readiness and are difficult to monitor due to Soldiers' reluctance to seek medical treatment. There is high risk of developing MSKIs while going through initial entry training (IET), many of which go unreported. The purposes of this study were to identify the contributing factors that influence US Army trainees to not seek medical care for self-reported symptoms of musculoskeletal injury (SMSKI) and establish how those factors may differ by sex, training school, and installation site.Materials and Methods: Data were collected from 739 trainees (607 males, 132 females) completing IET at either Fort Benning, GA, Fort Sill, OK or Fort Leonard-Wood, MO, USA. Male trainees were in combat arms jobs while female trainees were from both combat arms and other physically demanding jobs. All surveys were completed within 5 weeks of graduation from Advanced Individual Training and One Station Unit Training. Trainees answered a series of questions about SMSKIs sustained during IET that lasted seven or more days. Using a Likert-type scale (1-strongly disagree through 5-strongly agree), trainees rated the influence that each of the following seven statements contributed to their decision not to seek medical care: "graduating on time," "avoiding negative perceptions associated with injuries," "avoiding profile," "inconvenience in seeing a provider," "self-managing the injury based on past experience," "severity of the injury," and "prior negative experiences seeking medical care in the military." Pearson's Chi-square test was used to assess significant relationships among SMSKI reporting across sex, training school and training installation.Results: Overall, SMSKI incidence was 36.1% and 58.3% among IET male and female trainees, respectively (40% overall). Nearly two-thirds (64%) of all trainees injured during IET had a SMSKI that they did not report to leadership or a medical provider. Across sex, female trainees were more likely to report SMSKIs than male trainees (p < 0.01), but there was no difference in SMSKI reporting rates by sex (p = 0.48). There was a difference in SMSKI rates by training school (p < 0.01), where infantry had higher SMSKI rates than field artillery (p < 0.01). There were no differences across training schools in how often trainees sought medical care (p = 0.58). The most common reasons selected for not reporting SMSKIs (i.e., not seeking medical care) included "I wanted to graduate on time" and "I wanted to avoid a profile." "I had prior negative experiences seeking medical care in the military" was consistently rated as the least important reason. Female trainees were more likely to not report SMSKIs in order "to avoid a profile" than male trainees (p < 0.05).Conclusion: Over 64% of trainees' did not seek medical care for their SMSKI during IET. As early detection, better reporting and timely treatment may result in reductions in SMSKI severity, reduced IET attrition, and lower medical expenses, trainees should be encouraged to report SMSKIs for proper early stage treatment. These study findings could be used to assist military leadership to create a positive environment for reporting and seeking care for SMSKIs. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
- View/download PDF
22. Topanga: A kinetic ion plasma code for large-scale ionospheric simulations on magnetohydrodynamic timescales.
- Author
-
Belyaev, Mikhail A., Larson, David J., Cohen, Bruce I., and Clark, Stephen E.
- Subjects
- *
DISPLACEMENT currents (Electric) , *ELECTROMAGNETIC wave absorption , *NEUMANN boundary conditions , *MAXWELL equations , *OHM'S law , *ELECTROMAGNETIC pulses , *ELECTRON-ion collisions - Abstract
Topanga is a kinetic ion code developed for simulating large-scale plasma phenomena in the Earth's ionosphere on magnetohydrodynamic timescales. It is a domain-decomposed parallel code that runs on high-performance computing platforms. Features of Topanga include spherical geometry for simplified boundary conditions and computational efficiency; a hybrid plasma model with inertia-less fluid electrons, kinetic ions, and an electric field specified via an Ohm's law; a Maxwell-FDTD (finite difference time domain) plasma model which retains the displacement current in Maxwell's equations and models electron currents in the ionosphere with a tensor conductivity; sponge-layer boundary conditions for absorption of electromagnetic and plasma waves incident on the domain boundaries; and a novel mixed-implicit algorithm for evolving the EM fields inside the Maxwell-FDTD region that is stable over many orders of magnitude in the electron–ion collision frequency. We verify the numerical methods used in Topanga on a pair of test problems. The first test involves modeling a three-dimensional collisionless shock using the hybrid set of equations. The second test involves modeling a spherical TEM mode in vacuum using the Maxwell-FDTD set of equations. Finally, we demonstrate how using the combined set of hybrid and Maxwell-FDTD equations to model the Starfish Prime high-altitude nuclear test recovers a "missing" EM signal on the ground that is not present when using only the hybrid set of equations. The magnitude of this signal in the simulation containing the Maxwell-FDTD region agrees well with the E3a portion of the magnetohydrodynamic electromagnetic pulse from Starfish Prime. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
23. Antidepressant-Resistant Depression in Patients With Comorbid Subclinical Hypothyroidism or High-Normal TSH Levels.
- Author
-
Cohen, Bruce M., Sommer, Barbara R., and Vuckovic, Alexander
- Subjects
- *
SCHIZOPHRENIA treatment , *ANTIPSYCHOTIC agents , *TARGETED drug delivery , *PROTEIN-protein interactions , *DIAGNOSIS of schizophrenia , *ANTIDEPRESSANTS , *MENTAL depression , *HYPOTHYROIDISM , *THYROID gland function tests , *THYROTROPIN , *DISEASE complications - Abstract
The article discusses the action and mechanism of antipsychotic drugs in the treatment of Schizophrenia. Topics discussed include the pathogenesis and diagnosis of Schizophrenia, risk genes of polygenic disorders and protein-protein interactions among gene product. It also mentions risk genes like CHRN, PCDH and HCN families which may be suitable drug targets to treat symptoms of Schizophrenia.
- Published
- 2018
- Full Text
- View/download PDF
24. Finding a way forward: Policy reform of the Australian national electricity market.
- Author
-
Abbott, Malcolm and Cohen, Bruce
- Subjects
- *
ELECTRIC power consumption , *ELECTRIC industries , *ELECTRIC utility costs , *ELECTRIC rates , *COMMERCE - Abstract
Abstract On balance, it appears reform of the electricity sector has delivered considerable benefits for Australia, and for its individual states and territories. However, these changes have not been without cost, and as is often the case with major long-term reforms, ongoing implementation gives rise to a range of new challenges that need to be addressed, including security of supply and rising prices. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
25. The Relationship Between Soldier Performance on the Two-Mile Run and the 20-m Shuttle Run Test.
- Author
-
Canino, Maria C, Cohen, Bruce S, Redmond, Jan E, Sharp, Marilyn A, Zambraski, Edward J, and Foulis, Stephen A
- Subjects
- *
ARMY Physical Fitness Test , *HEALTH of military personnel , *MUSCLE strength , *AEROBIC capacity , *REGRESSION analysis , *EDUCATION of military personnel , *COMPARATIVE studies , *ELECTROCARDIOGRAPHY , *EXERCISE tests , *RESEARCH methodology , *MEDICAL cooperation , *RESEARCH , *RUNNING , *MILITARY personnel , *EVALUATION research , *BODY mass index - Abstract
Background: The 20-m shuttle run test (MSRT) is a common field test used to measure aerobic fitness in controlled environments. The U.S. Army currently assesses aerobic fitness with the two-mile run (TMR), but external factors may impact test performance. The aim of this study is to examine the relationship between the Army Physical Fitness Test TMR performance and the MSRT in military personnel.Methods: A group of 531 (403 males and 128 females) active duty soldiers (age: 24.0 ± 4.1 years) performed the MSRT in an indoor facility. Heart rate was monitored for the duration of the test. Post-heart rate and age-predicted maximal heart rate were utilized to determine near-maximal performance on the MSRT. The soldiers provided their most recent Army Physical Fitness Test TMR time (min). A Pearson correlation and multiple linear regression analyses were performed to examine the relationship between TMR time (min) and MSRT score (total number of shuttles completed). The study was approved by the Human Use Review Committee at the U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts.Findings: A significant, negative correlation exists between TMR time and MSRT score (r = -0.75, p < 0.001). Sex and MSRT score significantly predicted TMR time (adjusted R2 = 0.65, standard error of estimate = 0.97, p < 0.001) with a 95% ratio limits of agreement of ±12.6%. The resulting equation is: TMR = 17.736-2.464 × (sex) - 0.050 × (MSRT) - 0.026 × (MSRT × sex) for predicted TMR time. Males equal zero, females equal one, and MSRT score is the total number of shuttles completed.Discussion: The MSRT is a strong predictor of the TMR and should be considered as a diagnostic tool when assessing aerobic fitness in active duty soldiers. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
26. 258th ENMC international workshop Leigh syndrome spectrum: genetic causes, natural history and preparing for clinical trials 25-27 March 2022, Hoofddorp, Amsterdam, The Netherlands.
- Author
-
Diodato, Daria, Schiff, Manuel, Cohen, Bruce H., Bertini, Enrico, and Rahman, Shamima
- Subjects
- *
CLINICAL trials , *NEURODEGENERATION , *SYNDROMES , *GENETICS , *IN vivo studies - Abstract
• LSS is one of the more frequently occuring neurodegenerative disorders of childhood. • Several papers reported data from Leigh syndrome national registries worldwide. • The onset is mostly < 2 years of age. An early onset correlates with a worse outcome. • The diagnosis of LSS relies on clinical, neuroimaging and genetics findings. • Therapies are still lacking. Numerous compounds are being testing in vitro or in vivo. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
27. Acute and chronic effects of clozapine on cholinergic transmission in cultured mouse superior cervical ganglion neurons.
- Author
-
Saur, Taixiang, Cohen, Bruce M, Ma, Qi, Babb, Suzann M, Buttner, Edgar A, and Yao, Wei-Dong
- Subjects
- *
CLOZAPINE , *NICOTINIC receptors , *ANTIPSYCHOTIC agents , *DRUG efficacy , *COGNITION , *PEOPLE with schizophrenia - Abstract
Cholinergic dysfunction contributes to cognitive deficits in schizophrenia. The atypical antipsychotic clozapine improves cognition in patients with schizophrenia, possibly through modulation of the cholinergic system. However, little is known about specific underlying mechanisms. We investigated the acute and chronic effects of clozapine on cholinergic synaptic transmission in cultured superior cervical ganglion (SCG) neurons. Spontaneous excitatory postsynaptic currents (sEPSCs) were detected and were reversibly inhibited by the nicotinic receptor antagonist d-tubocurarine, confirming that the synaptic responses were primarily mediated by nicotinic receptors. Bath application of clozapine at therapeutic concentrations rapidly and reversely inhibited both the amplitude and frequency of sEPSCs in a concentration-dependent manner, without changing either rise or decay time, suggesting that clozapine effects have both presynaptic and postsynaptic origins. The acute effects of clozapine on sEPSCs were recapitulated by chronic treatment of SCG cultures with similar concentrations of clozapine, as clozapine treatment for 4 d reduced the frequency and amplitude of sEPSCs without affecting their kinetics. Cell survival analysis indicated that SCG neuron cell counts after chronic clozapine treatment were comparable to the control group. These results demonstrate that therapeutic concentrations of clozapine suppress nicotinic synaptic transmission in SCG cholinergic synapses, a simplein vitropreparation of cholinergic transmission. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
28. The privatization and de-privatization of rail industry assets in Australia and New Zealand.
- Author
-
Abbott, Malcolm and Cohen, Bruce
- Subjects
- *
RAILROADS , *PRIVATIZATION , *ECONOMIC policy , *ASSETS (Accounting) - Abstract
The rail sector globally has seen considerable reform in recent years. To date, the shape of reform has varied across jurisdictions, as has the nature of the rail operations being reformed. In numerous jurisdictions, the reform processes have encompassed the privatization of assets and operations. Unlike many other industries where privatization has occurred, however, the rail sector has experienced several instances where asset ownership and operations have been taken back into the hands of the government. In this paper, an examination is made of the privatization and de-privatization (or reverse privatization) of rail assets in three jurisdictions in Australia and New Zealand to see what insights can be drawn with regard to the factors that led to the failure of privatization and the government's reclaiming of control. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
29. Should Medical Insurance Review Serve the Patient's Best Interests? Examples and Considerations Illustrated by Behavioral Health Cases.
- Author
-
Harris, Peter Q., Abraham, Melissa E., and Cohen, Bruce M.
- Subjects
- *
HEALTH insurance , *HEALTH insurance companies , *MEDICAL quality control , *LEGAL liability - Abstract
Physician medical directors working for health care insurance companies conduct utilization reviews, participate in quality-of-care reviews, and adjudicate appeals. As a result, they have access to substantial and important clinical information. The medical director may have both current and historical information that can assist the treatment team in providing care. Sharing this information with a patient's current health care provider(s) is problematic due to concerns about patient privacy and the insurer's goal of not assuming legal liability for patient care. While this paper considers legal issues, it predominantly addresses the ethical responsibilities of medical directors who have valuable information unavailable to or unrecognized by the treatment team. Although it is important to consider sharing general medical information, this paper emphasizes the sharing of behavioral health information, which can be highly sensitive but also pertinent to psychiatric and other medical treatment choices. We suggest that clinical information should flow from insurer to provider when the insurer has information that will benefit the patient or prove crucial to optimal care rather than just flow from provider to insurer for the purposes of claims payments. To support and secure that flow, the paper outlines procedures for determining the need to share information, the means of providing that information, ways to separate liability, and processes for protecting privacy. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
30. Economics, ideology, and the creation and performance of state-owned electricity utilities in Australia, 1900 to 1950.
- Author
-
Abbott, Malcolm and Cohen, Bruce
- Subjects
- *
POST-World War II Period , *ELECTRICITY , *IDEOLOGY , *NINETEENTH century - Abstract
This paper examines the factors that contributed to the evolving structure and ownership of the electricity industry in Australia in the inter-war and immediate post-World War II period. It details how the industry developed in the Australian states from the latter part of the 19th century through the first half of the 20th century. In examining the industry's transformation, network effects, generation plant scales, and the influence of the conflicting ideologies of socialism versus private ownership are considered. It then provides an assessment of the impact the changes in structure collectively had on the industry's performance during this period. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
31. On the Validity of Certain Approximations Used in the Modeling of Nuclear EMP.
- Author
-
Farmer, William A., Cohen, Bruce I., and Eng, Chester D.
- Subjects
- *
SCATTERING (Physics) , *ELECTROMAGNETIC fields , *MAGNETIC fields , *MONTE Carlo method , *GAUSSIAN distribution , *ELECTRIC conductivity - Abstract
In legacy codes developed for the modeling of EMP, multiple scattering of Compton electrons has typically been modeled by the obliquity factor. A recent publication has examined this approximation in the context of the generated Compton current [W. A. Farmer and A. Friedman, IEEE Trans. Nucl. Sc. 62, 1695 (2015)]. Here, this previous analysis is extended to include the generation of the electromagnetic fields. Obliquity factor predictions are compared with Monte-Carlo models. In using a Monte-Carlo description of scattering, two distributions of scattering angles are considered: Gaussian and a Gaussian with a single-scattering tail. Additionally, legacy codes also neglect the radial derivative of the backward-traveling wave for computational efficiency. The neglect of this derivative improperly treats the backward-traveling wave. These approximations are examined in the context of a high-altitude burst, and it is shown that in comparison to more complete models, the discrepancy between field amplitudes is roughly two to three percent and between rise-times, 10%. Further, it is concluded that the biggest factor in determining the rise time of the signal is not the dynamics of the Compton current, but is instead the conductivity. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
32. Pilot Study of Intensive Chemotherapy With Peripheral Hematopoietic Cell Support for Children Less Than 3 Years of Age With Malignant Brain Tumors, the CCG-99703 Phase I/II Study. A Report From the Children's Oncology Group.
- Author
-
Cohen, Bruce H, Geyer, J Russell, Miller, Douglas C, Curran, John G, Zhou, Tianni, Holmes, Emi, Ingles, Sue Ann, Dunkel, Ira J, Hilden, Joanne, Packer, Roger J, Pollack, Ian F, Gajjar, Amar, Finlay, Jonathan L, and Children's Oncology Group
- Abstract
Background: The primary goals of the Children's Cancer Group 99703 study were to assess the feasibility and tolerability of-as well as the response rate to-a novel dose-intensive chemotherapy regimen.Methods: Between March 1998 and October 2004, 92 eligible patients were enrolled. Following biopsy/resection, patients received three identical cycles of Induction chemotherapy (vincristine, cyclophosphamide, etoposide, and cisplatin) administered every 21-28 days. Patients without tumor progression then received three consolidation cycles of marrow-ablative chemotherapy (thiotepa and carboplatin) followed by autologous hematopoietic cell rescue.Results: The maximum tolerated dose of thiotepa was 10 mg/kg/day × 2 days per cycle. The toxic mortality rate was zero during induction and 2.6% during consolidation. Centrally evaluated response rates to induction and consolidation in evaluable patients with residual tumor were 73.3% and 66.7%, respectively. Disease progression rates on induction and consolidation were 4%. Five-year event-free survival and overall survival were 43.9 ± 5.2% and 63.6 ± 5% respectively. Gross total resection versus less than gross total resection were the only significant outcome comparisons: 5-year maximum tolerated dose and overall survival of 54.4 ± 7% versus 28.9 ± 7% (P = 0.0065) and 75.9 ± 8% versus 48.7 ± 8% (P = 0.0034), respectively. The 5-year maximum tolerated dose for localized (M0) versus metastatic (M1+) medulloblastoma was 67.5 ± 9.5% versus 30 ± 14.5% (P = 0.007). The 5-year maximum tolerated dose and overall survival for desmoplastic medulloblastoma patients versus other medulloblastoma were 78.6 ± 11% versus 50.5 ± 12% (P = 0.038) and 85.7 ± 9.4% versus 60.6 ± 11.6% (P = 0.046), respectively.Conclusions: This phase I dose-escalation study of marrow-ablative thiotepa regimen determined a maximum tolerated dose that had acceptable toxicity. Overall survival data justify this strategy for current Children's Oncology Group studies. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF
33. Pilot Study of Intensive Chemotherapy With Peripheral Hematopoietic Cell Support for Children Less Than 3 Years of Age With Malignant Brain Tumors, the CCG-99703 Phase I/II Study. A Report From the Children's Oncology Group.
- Author
-
Cohen, Bruce H., Geyer, J. Russell, Miller, Douglas C., Curran, John G., Zhou, Tianni, Holmes, Emi, Ingles, Sue Ann, Dunkel, Ira J., Hilden, Joanne, Packer, Roger J., Pollack, Ian F., Gajjar, Amar, and Finlay, Jonathan L.
- Subjects
- *
CANCER chemotherapy , *HEMATOPOIETIC stem cells , *BRAIN tumors , *JUVENILE diseases , *PILOT projects , *ONCOLOGY research - Abstract
Background The primary goals of the Children's Cancer Group 99703 study were to assess the feasibility and tolerability of—as well as the response rate to—a novel dose-intensive chemotherapy regimen. Methods Between March 1998 and October 2004, 92 eligible patients were enrolled. Following biopsy/resection, patients received three identical cycles of Induction chemotherapy (vincristine, cyclophosphamide, etoposide, and cisplatin) administered every 21-28 days. Patients without tumor progression then received three consolidation cycles of marrow-ablative chemotherapy (thiotepa and carboplatin) followed by autologous hematopoietic cell rescue. Results The maximum tolerated dose of thiotepa was 10 mg/kg/day × 2 days per cycle. The toxic mortality rate was zero during induction and 2.6% during consolidation. Centrally evaluated response rates to induction and consolidation in evaluable patients with residual tumor were 73.3% and 66.7%, respectively. Disease progression rates on induction and consolidation were 4%. Five-year event-free survival and overall survival were 43.9 ± 5.2% and 63.6 ± 5% respectively. Gross total resection versus less than gross total resection were the only significant outcome comparisons: 5-year maximum tolerated dose and overall survival of 54.4 ± 7% versus 28.9 ± 7% ( P = 0.0065) and 75.9 ± 8% versus 48.7 ± 8% ( P = 0.0034), respectively. The 5-year maximum tolerated dose for localized (M0) versus metastatic (M1+) medulloblastoma was 67.5 ± 9.5% versus 30 ± 14.5% ( P = 0.007). The 5-year maximum tolerated dose and overall survival for desmoplastic medulloblastoma patients versus other medulloblastoma were 78.6 ± 11% versus 50.5 ± 12% ( P = 0.038) and 85.7 ± 9.4% versus 60.6 ± 11.6% ( P = 0.046), respectively. Conclusions This phase I dose-escalation study of marrow-ablative thiotepa regimen determined a maximum tolerated dose that had acceptable toxicity. Overall survival data justify this strategy for current Children's Oncology Group studies. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
34. One-dimensional particle simulations of Knudsen-layer effects on D-T fusion.
- Author
-
Cohen, Bruce I., Dimits, Andris M., Zimmerman, George B., and Wilks, Scott C.
- Subjects
- *
PARTICLE physics , *PLASMA sources , *PLASMA interactions , *NONLINEAR theories , *COLLISIONAL plasma , *SIMULATION methods & models - Abstract
Particle simulations are used to solve the fully nonlinear, collisional kinetic equation describing the interaction of a high-temperature, high-density, deuterium-tritium plasma with absorbing boundaries, a plasma source, and the influence of kinetic effects on fusion reaction rates. Both hydrodynamic and kinetic effects influence the end losses, and the simulations show departures of the ion velocity distributions from Maxwellian due to the reduction of the population of the highest energy ions (Knudsen-layer effects). The particle simulations show that the interplay between sources, plasma dynamics, and end losses results in temperature anisotropy, plasma cooling, and concomitant reductions in the fusion reaction rates. However, for the model problems and parameters considered, particle simulations show that Knudsen-layer modifications do not significantly affect the velocity distribution function for velocities most important in determining the fusion reaction rates, i.e., the thermal fusion reaction rates using the local densities and bulk temperatures give good estimates of the kinetic fusion reaction rates. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
35. Mitochondrial Disease: Clinical Aspects, Molecular Mechanisms, Translational Science, and Clinical Frontiers.
- Author
-
Thornton, Ben, Cohen, Bruce, Copeland, William, and Maria, Bernard L.
- Subjects
- *
MITOCHONDRIAL pathology , *OXIDATIVE phosphorylation , *ACIDOSIS , *NEUROBIOLOGY , *IMMUNOLOGIC diseases , *NEUROLOGY , *JUVENILE diseases - Abstract
Mitochondrial medicine provides a metabolic perspective on the pathology of conditions linked with inadequate oxidative phosphorylation. Dysfunction in the mitochondrial machinery can result in improper energy production, leading to cellular injury or even apoptosis. Clinical presentations are often subtle, so clinicians must have a high index of suspicion to make early diagnoses. Symptoms could include muscle weakness and pain, seizures, loss of motor control, decreased visual and auditory functions, metabolic acidosis, acute developmental regression, and immune system dysfunction. The 2013 Neurobiology of Disease in Children Symposium, held in conjunction with the 42nd Annual Meeting of the Child Neurology Society, aimed to (1) describe accepted clinical phenotypes of mitochondrial disease produced from various mitochondrial mutations, (2) discuss contemporary understanding of molecular mechanisms that contribute to disease pathology, (3) highlight the systemic effects produced by dysfunction within the mitochondrial machinery, and (4) introduce current strategies that are being translated from bench to bedside as potential therapeutics. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
36. Affordable Care Act standards for race and ethnicity mask disparities in maternal smoking during pregnancy.
- Author
-
Hawkins, Summer Sherburne and Cohen, Bruce B.
- Subjects
- *
ETHNICITY , *RACIAL differences , *MEDICAL care , *PREGNANT women , *WOMEN'S tobacco use , *COMPARATIVE studies ,PATIENT Protection & Affordable Care Act - Abstract
This study compared maternal smoking during pregnancy between the new Patient Protection and Affordable Care Act (ACA) data collection standards and Federal Office of Management and Budget (OMB) standards. Method Data were from the Massachusetts Standard Certificate of Live Births on 1,156,472 babies from 1996 to 2010. A parent reported whether the mother smoked during pregnancy (yes/no), her race (5 options) and, separately, her ethnicity (39 categories). Prenatal smoking rates were compared between the ACA and OMB standards. Detailed ethnicity from the birth certificate was then examined within all broad categories of the ACA standards: White, Black/African American, Other Hispanic, Other Asian/Pacific Islander, and Other categories. Results For Hispanic/Latina and Asian mothers, the ACA standards captured the variability in smoking across and within racial/ethnic groups more than the OMB standards. However, for White and Black/African American mothers, the broad ACA categories masked striking differences in prenatal smoking. While the overall prevalence among Whites was 10.2%, this ranged from 0.8% for Iranians to 21.0% for Cape Verdeans. Among Black/African Americans (7.6%), this ranged from 0.5% for Nigerians to 12.9% for African Americans. The ACA standards also combined ethnic groups with sizeable populations into Other Hispanics and Other Asian/Pacific Islanders. Conclusion When population health surveys and other reporting tools are being revised, state and federal agencies should consider expanding all race/ethnicity categories to capture detailed ethnicity on everyone. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
37. Recall of treatment information by patients in a first episode psychosis outpatient clinic.
- Author
-
Lewandowski, Kathryn E., Ongur, Dost, and Cohen, Bruce M.
- Subjects
- *
PSYCHOSES , *THERAPEUTICS - Published
- 2023
- Full Text
- View/download PDF
38. THE PSYCHIATRIC HEGEMON AND THE LIMITS OF RESISTANCE.
- Author
-
COHEN, BRUCE M. Z.
- Subjects
- *
MENTAL health personnel , *SOCIAL workers , *RESISTANCE in psychotherapy , *DEFENSE mechanisms (Psychology) , *MENTAL illness - Published
- 2016
- Full Text
- View/download PDF
39. The accountability of ministerial staff in Australia.
- Author
-
Abbott, Malcolm and Cohen, Bruce
- Subjects
- *
GOVERNMENT accountability , *MINISTERIAL responsibility , *PUBLIC administration , *POLITICAL change , *CIVIL service , *FREEDOM of information , *POLITICAL corruption ,AUSTRALIAN politics & government, 1945- - Abstract
It is a reasonable community expectation that ministerial staff who enjoy the privilege of working at the interface of politics and public administration in Australia are subject to appropriate accountability measures. The key questions are what measures currently exist to hold ministerial staff accountable, how effective are such measures, and how could accountability be improved. While descriptions of an ‘accountability black hole’ for ministerial staff are overstated, the measures now in place do not operate uniformly across Australian jurisdictions, have on occasion developed in an ad hoc fashion and are sometimes uncertain in their application. Such circumstances highlight the need for reform, which may potentially encompass both accountability mechanisms directly applicable to ministerial staff, as well as measures that operate more broadly and apply to those with whom ministerial staff interact. 在政治与公共管理交合处工作的澳大利亚内阁工作人员需要 接受适当的问责,这是一种合情合理的社会期待。关键的问题在于目前都有哪些手段能对他们问责,这些手段能否改进。设计问责方法的关键因素是内阁工作人员特殊角色和责任,其不同于非政治的公务员,也不同于作为决策者并直接参加公共辩论的大臣。说内阁工作人员为“问责黑洞”未免言过其实,但现在的那些方法在所有澳大利亚司法辖区并未统一运行,有时以特事特办的方式存在,往往在应用上含糊不定。这种状况说明需要改革。改革可以囊括直接适用于内阁工作人员的问责机制,以及涵盖更广、适用于与他们打交道的那些人的办法。 [ABSTRACT FROM PUBLISHER]
- Published
- 2014
- Full Text
- View/download PDF
40. Therapy optimization in multiple sclerosis: a prospective observational study of therapy compliance and outcomes.
- Author
-
Coyle, Patricia K., Cohen, Bruce A., Leist, Thomas, Markowitz, Clyde, Oleen-Burkey, MerriKay, Schwartz, Marc, Tullman, Mark J., and Zwibel, Howard
- Subjects
- *
THERAPEUTICS , *MULTIPLE sclerosis , *LEGAL compliance , *PATIENTS , *CLINICAL trials - Abstract
Background: Data sources for MS research are numerous but rarely provide an objective measure of drug therapy compliance coupled with patient-reported health outcomes. The objective of this paper is to describe the methods and baseline characteristics of the Therapy Optimization in MS (TOP MS) study designed to investigate the relationship between disease-modifying therapy compliance and health outcomes. Methods: TOP MS was designed as a prospective, observational, nationwide patient-focused study using an internet portal for data entry. The protocol was reviewed and approved by Sterling IRB. The study was registered with ClinicalTrials.gov. It captured structured survey data monthly from MS patients recruited by specialty pharmacies. Data collection included the clinical characteristics of MS such as MS relapses. Disability, quality of life and work productivity and activity impairment were assessed quarterly with well-validated scales. When events like severe fatigue or new or worsening depression were reported, feedback was provided to treating physicians. The therapy compliance measure was derived from pharmacy drug shipment records uploaded to the study database. The data presented in this paper use descriptive statistics. Results: The TOP MS Study enrolled 2966 participants receiving their disease-modifying therapy (DMT) from specialty pharmacies. The mean age of the sample was 49 years, 80.4% were female, 89.9% were Caucasian and 55.7% were employed full or part time. Mean time since first symptoms was 11.5 years; mean duration since diagnosis was 9.5 years. Patient-reported EDSS was 3.5; 72.2% had a relapsing-remitting disease course. The most commonly reported symptoms at the time of enrollment were fatigue (74.7%), impaired coordination or balance (61.8%) and numbness and tingling (61.2%). Half of the sample was using glatiramer acetate and half was using beta-interferons. Conclusion: Demographic and clinical characteristics of the TOP MS sample at enrollment are consistent with other community-based MS samples, and the sample appears to be representative of DMT users in the US. TOP MS data can be used to explore the associations between disease-modifying therapy compliance and health outcomes. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
41. Accuracy of Assisted Reproductive Technology Information on Birth Certificates: Florida and Massachusetts, 2004-06.
- Author
-
Cohen, Bruce, Bernson, Dana, Sappenfield, William, Kirby, Russell S., Kissin, Dmitry, Zhang, Yujia, Copeland, Glenn, Zhang, Zi, and Macaluso, Maurizio
- Subjects
- *
REPRODUCTIVE technology , *HUMAN fertility , *CHILDBIRTH , *BIRTH certificates , *PREGNANCY complications , *DELIVERY (Obstetrics) - Abstract
Background Assisted Reproductive Technology ( ART) includes fertility procedures where both egg and sperm are handled in the lab. ART use has increased considerably in recent years, accounting for 47 090 livebirths in the US in 2010. ART increases the probability of multiple gestation births, which are at higher risks than singletons for adverse outcomes. Additionally, ART is associated with a greater risk of complications during pregnancy, labour, and delivery, and increased risk of adverse perinatal outcomes in singleton births. Methods We merged Florida and Massachusetts birth records from 2004-06 with the National ART Surveillance System ( NASS) and using NASS as the gold standard, calculated sensitivity, specificity, and positive predictive value ( PPV) of ART reporting on the birth certificates by maternal, infant, and hospital characteristics. We fit random-effects logistic regression models to evaluate simultaneously the association of ART reporting with these predictors while accounting for correlation among births occurring in the same hospital. Results Sensitivity of ART reporting on the birth certificate was 28.9% in Florida and 41.4% in Massachusetts. Specificity was >99% in both states. PPV was 45.5% in Florida and 54.6% in Massachusetts. The odds of ART reporting varied by state and by several maternal and delivery characteristics including age, parity, history of fetal loss, plurality, race/Hispanic ethnicity, delivery payment source, pre-existing conditions, and complications during pregnancy or labour and delivery. Conclusions There was significant under-reporting of ART procedures on the birth certificates. Using data on ART births identified only from birth certificates yields a biased sample of the population of ART births. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
42. A PIC-Fluid Hybrid Algorithm for Multiscale Simulations of Laser-Plasma Interactions.
- Author
-
Cohen, Bruce I., Dimits, Andris M., Divol, Laurent, Fiuza, Frederico, Kemp, Andreas J., and Strozzi, David J.
- Subjects
- *
LASER-plasma interactions , *ALGORITHM research , *LASER plasmas , *LASERS in physics , *NUMERICAL analysis , *PLASMA physics , *COLLISIONS (Nuclear physics) , *SIMULATION methods & models - Abstract
A recently introduced algorithm for performing integrated kinetic simulations of the fast ignition approach to laser fusion is reviewed. The integrated algorithm uses a conventional fully electromagnetic relativistic particle-in-cell algorithm in vacuum and plasma up to a density well above cutoff for the incident laser, above which density the plasma is sufficiently collisional so that light waves and electron plasma waves are unimportant and a simplified physics model is justified that leads to improved computational efficiencies. Integrated comprehensive kinetic simulation of fast ignition is rendered more practical with this two-region algorithm. Professor C. K. Birdsall was a pioneer in computational plasma physics and enthusiastically championed the expansion of its use for discovery science and to simulate plasma phenomena in a wall-to-wall manner. [ABSTRACT FROM PUBLISHER]
- Published
- 2014
- Full Text
- View/download PDF
43. Constructing an adaptive care model for the management of disease-related symptoms throughout the course of multiple sclerosis—performance improvement CME.
- Author
-
Miller, Aaron E, Cohen, Bruce A, Krieger, Stephen C, Markowitz, Clyde E, Mattson, David H, and Tselentis, Helen N
- Subjects
- *
MULTIPLE sclerosis , *VIRUS diseases , *MOVEMENT disorders , *MUSCLE diseases , *SPASTICITY - Abstract
The article discusses a study which was aimed to design a performance improvement continuing medical education (PI CME) activity for better clinical management of multiple sclerosis (MS)-related depression, fatigue, mobility impairment/falls, and spasticity. The study concluded that its PI CME interventions demonstrated performance improvement in the management of MS-related symptoms.
- Published
- 2014
- Full Text
- View/download PDF
44. Measuring Physical Activity During US Army Basic Combat Training: A Comparison of 3 Methods.
- Author
-
Redmond, Jan E., Cohen, Bruce S., Simpson, Kathleen, Spiering, Barry A., and Sharp, Marilyn A.
- Subjects
- *
PHYSICAL activity , *MILITARY education , *EXERCISE , *ACCELEROMETERS - Abstract
Background: An understanding of the demands of physical activity (PA) during US Army Basic Combat Training (BCT) is necessary to support Soldier readiness and resilience. The purpose of this study was to determine the agreement among 3 different PA measurement instruments in the BCT environment. Methods: Twenty-four recruits from each of 11 companies wore an ActiGraph accelerometer (Actigraph, LLC, Pensacola, FL) and completed a daily PA log during 8 weeks of BCT at 2 different training sites. The PA of one recruit from each company was recorded using PAtracker, an Army-developed direct observation tool. Information obtained from the accelerometer, PA log, and PAtracker included time spent in various types of PA, body positions, PA intensities, and external loads carried. Pearson product moment correlations were run to determine the strength of association between the ActiGraph and PAtracker for measures of PA intensity and between the PAtracker and daily PA log for measures of body position and PA type. The Bland-Altman method was used to assess the limits of agreement (LoA) between the measurement instruments. Results: Weak correlations (r = -0.052 to r = 0.302) were found between the ActiGraph and PAtracker for PA intensity. Weak but positive correlations (r = 0.033 to r = 0.268) were found between the PAtracker and daily PA log for body position and type of PA. The 95% LoA for the ActiGraph and PAtracker for PA intensity were in disagreement. The 95% LoA for the PAtracker and daily PA log for standing and running and all PA types were in disagreement; sitting and walking were in agreement. Conclusions: The ActiGraph accelerometer provided the best measure of the recruits' PA intensity while the PAtracker and daily PA log were best for capturing body position and type of PA in the BCT environment. The use of multiple PA measurement instruments in this study was necessary to best characterize the physical demands of BCT. [ABSTRACT FROM AUTHOR]
- Published
- 2013
45. Neuropsychological functioning predicts community outcomes in affective and non-affective psychoses: A 6-month follow-up.
- Author
-
Lewandowski, Kathryn E., Cohen, Bruce M., Keshavan, Matcheri S., Sperry, Sarah H., and Öngür, Dost
- Subjects
- *
NEUROPSYCHOLOGY , *PSYCHOSES , *FOLLOW-up studies (Medicine) , *PREDICTION (Psychology) , *COMMUNITIES , *COGNITION disorders , *BIPOLAR disorder , *SYMPTOMS - Abstract
Abstract: Introduction: Neurocognitive dysfunction is a major symptom feature of schizophrenia and bipolar disorder. A prognostic relationship between cognition and community outcomes is well-documented in schizophrenia and increasingly recognized in bipolar disorder. However, specific associations among neurocognition, diagnosis, state symptomatology, and community functioning are unclear, and few studies have compared these relationships among patients with affective and non-affective psychoses in the same study. We examined neurocognitive, clinical, and community functioning in a cross-diagnostic sample of patients with psychotic disorders over a 6-month follow-up interval. Method: Neurocognitive, clinical and community functioning were assessed in participants with schizophrenia (n =13), schizoaffective disorder (n =17), or bipolar disorder with psychosis (n =18), and healthy controls (n =18) at baseline and 6months later. Results: Neurocognitive functioning was impaired in all diagnostic groups and, despite reductions in primary symptoms, did not recover on most measures over the follow-up period. Neurocognitive impairment was not associated with diagnosis or clinical improvement. Several neurocognitive scores at baseline (but not diagnosis or clinical baseline or follow-up scores) predicted community functioning at follow-up. Discussion: In one of the few studies to longitudinally examine neurocognition in association with clinical and outcomes variables in a cross diagnostic sample of psychotic disorders patients, neurocognitive deficits were pronounced across diagnoses and did not recover on most measures despite significant reductions in clinical symptoms. Baseline neurocognitive functioning was the only significant predictor of patients' community functioning six months later. Efforts to recognize and address cognitive deficits, an approach that has shown promise in schizophrenia, should be extended to all patients with psychosis. [Copyright &y& Elsevier]
- Published
- 2013
- Full Text
- View/download PDF
46. An Engineered Glutamate-gated Chloride (GluCl) Channel for Sensitive, Consistent Neuronal Silencing by Ivermectin.
- Author
-
Frazier, Shawnalea J., Cohen, Bruce N., and Lester, Henry A.
- Subjects
- *
GLUTAMIC acid , *CHLORIDE channels , *ANTHELMINTICS , *IVERMECTIN , *GENE expression , *ENDOPLASMIC reticulum - Abstract
A modified invertebrate glutamate-gated Cl- channel (GluCl αβ) was previously employed to allow pharmacologically induced silencing of electrical activity in CNS neurons upon exposure to the anthelmintic drug ivermectin (IVM). Usefulness of the previous receptor was limited by 1) the high concentration of IVM necessary to elicit a consistent silencing phenotype, raising concern about potential side effects, and 2) the variable extent of neuronal spike suppression, due to variations in the co-expression levels of the fluorescent protein-tagged α and β subunits. To address these issues, mutant receptors generated via rational protein engineering strategies were examined for improvement. Introduction of a gain-of-function mutation (L9'F) in the second transmembrane domain of the α subunit appears to facilitate β subunit incorporation and substantially increase heteromeric GluCl αβ sensitivity to IVM. Removal of an arginine-based endoplasmic reticulum retention motif (RSR mutated to AAA) from the intracellular loop of the β subunit further promotes heteromeric expression at the plasma membrane possibly by preventing endoplasmic reticulum-associated degradation of theβ subunit rather than simply reducing endoplasmic reticulum retention. A monomeric XFP (mXFP) mutation that prevents fluorescent protein dimerization complements the mutant channel effects. Expression of the newly engineered GluCl opt α-mXFP L9'F + opt β-mXFP Y182F RSR_AAA receptor in dissociated neuronal cultures markedly increases conductance and reduces variability in spike suppression at 1 nM IVM. This receptor, named "GluClv2.0," is an improved tool for IVM-induced silencing. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
47. Alpers-Huttenlocher Syndrome
- Author
-
Saneto, Russell P., Cohen, Bruce H., Copeland, William C., and Naviaux, Robert K.
- Subjects
- *
NEURODEGENERATION , *MITOCHONDRIAL pathology , *GENETIC mutation , *MITOCHONDRIAL DNA , *DNA polymerases , *DELETION mutation , *ENZYME kinetics - Abstract
Abstract: Alpers-Huttenlocher syndrome is an uncommon mitochondrial disease most often associated with mutations in the mitochondrial DNA replicase, polymerase-γ. Alterations in enzyme activity result in reduced levels or deletions in mitochondrial DNA. Phenotypic manifestations occur when the functional content of mitochondrial DNA reaches a critical nadir. The tempo of disease progression and onset varies among patients, even in identical genotypes. The classic clinical triad of seizures, liver degeneration, and progressive developmental regression helps define the disorder, but a wide range of clinical expression occurs. The majority of patients are healthy before disease onset, and seizures herald the disorder in most patients. Seizures can rapidly progress to medical intractability, with frequent episodes of epilepsia partialis continua or status epilepticus. Liver involvement may precede or occur after seizure onset. Regardless, eventual liver failure is common. Both the tempo of disease progression and range of organ involvement vary from patient to patient, and are only partly explained by pathogenic effects of genetic mutations. Diagnosis involves the constellation of organ involvement, not the sequence of signs. This disorder is relentlessly progressive and ultimately fatal. [Copyright &y& Elsevier]
- Published
- 2013
- Full Text
- View/download PDF
48. A grid-based binary model for coulomb collisions in plasmas
- Author
-
Cohen, Bruce I., Dimits, Andris M., and Strozzi, David J.
- Subjects
- *
BINARY number system , *MATHEMATICAL models , *COULOMB functions , *LANGEVIN equations , *PARTICLES , *ALGEBRAIC field theory , *PLASMA gases - Abstract
Abstract: Both binary and grid-based Langevin equations models for Coulomb collisions are used in particle simulation of plasmas. We introduce a variant of the conventional binary collision algorithm for performing Coulomb collisions. In this algorithm particles in a configuration space cell are not paired for collisions. Instead, for every test particle in the cell, a unique field particle is defined by randomly sampling a velocity distribution defined on the grid by accumulating moments of the particle distribution function(s). The test and field particle pair then undergoes a collision using the standard methodology for binary collisions. The performance of the new algorithm is illustrated in example computations and compared to a drag-diffusion Langevin equations algorithm. The grid-based algorithms do not conserve momentum and energy, although with good particle statistics the non-conservation is relatively small. Conservation can be restored after collisions using a shift and scaling of the momenta. The comparative merits of the new algorithm are discussed. [Copyright &y& Elsevier]
- Published
- 2013
- Full Text
- View/download PDF
49. Probabilistic Linkage of Assisted Reproductive Technology Information with Vital Records, Massachusetts 1997-2000.
- Author
-
Zhang, Yujia, Cohen, Bruce, Macaluso, Maurizio, Zhang, Zi, Durant, Tonji, and Nannini, Angela
- Subjects
- *
ALGORITHMS , *BIRTH certificates , *BIRTH weight , *CONFIDENCE intervals , *DATABASES , *HUMAN reproductive technology , *INFANT mortality , *LONGITUDINAL method , *MEDICAL record linkage , *MULTIPLE birth , *PROBABILITY theory , *WOMEN'S health , *PARITY (Obstetrics) , *DATA analysis software , *DESCRIPTIVE statistics ,RESEARCH evaluation - Abstract
To assess the validity of probabilistic linkage (PL) in combining national surveillance data on assisted reproductive technology (ART) with Massachusetts birth and infant death data, for the purpose of monitoring maternal and child health outcomes of ART. A study conducted in 2006 utilized direct identifiers to match Massachusetts birth records with records on ART procedures performed to Massachusetts residents in fertility clinics located in Massachusetts and Rhode Island, achieving a linkage rate of 87.5%. The present study employed PL using the program Link Plus, without access to direct identifiers. The primary linking variables were maternal and infant dates of birth, and plurality. Ancillary variables such as maternal ZIP code and gravidity helped resolve duplicate matches and capture additional matches. PL linked 5,390 (87.8%) of 6,139 deliveries, correctly identifying 96.4% of the matches previously obtained using deterministic linkage methods. PL yielded a high linkage rate with satisfactory validity; this method may be applied in other states to help monitor the maternal and child health outcomes of ART. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
50. The performance of the urban water and wastewater sectors in Australia
- Author
-
Abbott, Malcolm, Cohen, Bruce, and Wang, Wei Chun
- Subjects
- *
SEWAGE , *MUNICIPAL water supply , *PLANT performance , *DATA envelopment analysis , *CORPORATIZATION - Abstract
Abstract: Substantial structural reform has occurred in the water and wastewater sectors of Australia’s major urban centers over the past two decades. This reform has involved the corporatization of government assets and some vertical and horizontal separation. This paper analyses the performance of these sectors since the mid 1990s. In particular, it uses Malmquist Data Envelopment Analysis (DEA) to determine the different levels of productivity and efficiency improvement over this period. The results point to modest, but positive productivity gains in the larger urban centers, independent of industry structure. Further, it highlights the need to consider exogenous factors that can influence productivity outcomes in an industry generally associated with monopoly characteristics and dependent on water sources that are, to varying extents, unpredictable and uncontrollable. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.