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1.
Phys Rev Lett ; 125(13): 133201, 2020 Sep 25.
Article in English | MEDLINE | ID: mdl-33034483

ABSTRACT

Nonlinear self-guided propagation of intense long-wave infrared (LWIR) laser pulses is of significant recent interest, as it promises high power transmission without beam breakup and multifilamentation. Central to self-guiding is the mechanism for the arrest of self-focusing collapse. Here, we show that discrete avalanche sites centered on submicron aerosols can arrest self-focusing, providing a new mechanism for self-guided propagation of moderate intensity LWIR pulses in outdoor environments. Our conclusions are supported by simulations of LWIR pulse propagation using an effective index approach that incorporates the time-resolved plasma dynamics of discrete avalanche breakdown sites.

2.
Phys Rev Lett ; 124(1): 013201, 2020 Jan 10.
Article in English | MEDLINE | ID: mdl-31976702

ABSTRACT

Strong-field ionization is central to intense laser-matter interactions. However, standard ionization measurements have been limited to extremely low density gas samples, ignoring potential high density effects. Here, we measure strong-field ionization in atmospheric pressure range air, N_{2}, and Ar over 14 decades of absolute yield, using mid-IR picosecond avalanche multiplication of single electrons. Our results are consistent with theoretical rates for isolated atoms and molecules and quantify the ubiquitous presence of ultralow concentration gas contaminants that can significantly affect laser-gas interactions.

3.
J Neonatal Perinatal Med ; 9(4): 333-339, 2016.
Article in English | MEDLINE | ID: mdl-28009336

ABSTRACT

OBJECTIVE: We sought to determine whether hypocortisolism is associated with preterm birth, using hair cortisol as a marker of long term hypothalamic-pituitary-adrenal axis activity. STUDY DESIGN: In a prospective, matched, case-control study, 29 women who had a preterm birth at 24-36w5d gestation were compared to 29 women who delivered at term, matched for maternal age, gestational age, and ethnicity. Cases' samples were collected within 72 h of preterm birth and controls at the same gestational age as the corresponding case. Participants completed validated questionnaires regarding general stress and childhood trauma. The Wilcoxon signed-rank test was used to compare the distribution of mean hair cortisol scores between cases and controls. Conditional logistic regression was used to predict case vs. control by hair cortisol score, controlling for relevant covariates. RESULTS: Baseline characteristics of cases and controls did not differ. Hair cortisol levels were significantly lower among cases in the adjusted analysis. Hair cortisol level was a predictor of case versus control. Each 10-pg.mg-1 increase in hair cortisol level was associated with an estimated 33% decreased odds of being a case. The only significant difference in the validated questionnaires was an increased measure of emotional neglect in the preterm group. CONCLUSION: Our study suggests that women who deliver prematurely may have lower hair cortisol levels than women who deliver at term. Normal hypothalamic-pituitary-adrenal axis activation is a physiologic, adaptive response to stress. One hypothesis to explain our results are that women who are stressed, but unable to mount an adequate stress response could be at particular risk for preterm birth.


Subject(s)
Adult Survivors of Child Adverse Events , Hydrocortisone/metabolism , Premature Birth/metabolism , Stress, Psychological/metabolism , Adult , Adult Survivors of Child Adverse Events/psychology , Case-Control Studies , Female , Gestational Age , Hair/chemistry , Humans , Hypothalamo-Hypophyseal System , Logistic Models , Maternal Age , Odds Ratio , Pilot Projects , Pituitary-Adrenal System , Pregnancy , Premature Birth/epidemiology , Premature Birth/psychology , Prospective Studies , Stress, Psychological/epidemiology , Stress, Psychological/psychology , Surveys and Questionnaires
4.
BMC Med Inform Decis Mak ; 16: 75, 2016 06 24.
Article in English | MEDLINE | ID: mdl-27343060

ABSTRACT

BACKGROUND: The use of telemonitoring is a promising approach to optimizing outcomes in the treatment of heart failure (HF) for patients living in the community. HF telemonitoring interventions, however, have not been tested for use with individuals residing in disparity communities. METHODS: The current study describes the results of a community based participatory research approach to adapting a telemonitoring HF intervention so that it is acceptable and feasible for use with a lower-income, Black and Hispanic patient population. The study uses the ADAPT-ITT framework to engage key community stakeholders in the process of adapting the intervention in the context of two consecutive focus groups. In addition, data from a third focus group involving HF telemonitoring patient participants was also conducted. All three focus group discussions were audio recorded and professionally transcribed and lasted approximately two hours each. Structural coding was used to mark responses to topical questions in the interview guide. RESULTS: This is the first study to describe the formative process of a community-based participatory research study aimed at optimizing telehealth utilization among African-American and Latino patients from disparity communities. Two major themes emerged from qualitative analyses of the focus group data. The first theme that arose involved suggested changes to the equipment that would maximize usability. Subthemes identified included issues that reflect the patient populations targeted, such as Spanish translation, font size and medical jargon. The second theme that arose involved suggested changes to the RCT study structure in order to maximize participant engagement. Subthemes also identified issues that reflect concerns of the targeted patient populations, such as the provision of reassurances regarding identity protection to undocumented patients in implementing an intervention that utilizes a camera, and that their involvement in telehealth monitoring would not replace their clinic care, which for many disparity patients is their only connection to medical care. CONCLUSIONS: The adaptation, based on the analysis of the data from the three focus groups, resulted in an intervention that is acceptable and feasible for HF patients residing in disparity communities. TRIAL REGISTRATION: NCT02196922 ; ClinicalTrials.gov (US National Institutes of Health).


Subject(s)
Black or African American , Community-Based Participatory Research/methods , Heart Failure/diagnosis , Hispanic or Latino , Monitoring, Ambulatory/methods , Qualitative Research , Telemedicine/methods , Community-Based Participatory Research/standards , Healthcare Disparities , Heart Failure/therapy , Humans , Monitoring, Ambulatory/standards , Telemedicine/standards
5.
Clin Exp Immunol ; 182(3): 289-301, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26332605

ABSTRACT

VRC-HIVMAB060-00-AB (VRC01) is a broadly neutralizing HIV-1 monoclonal antibody (mAb) isolated from the B cells of an HIV-infected patient. It is directed against the HIV-1 CD4 binding site and is capable of potently neutralizing the majority of diverse HIV-1 strains. This Phase I dose-escalation study in healthy adults was conducted at the National Institutes of Health (NIH) Clinical Center (Bethesda, MD, USA). Primary objectives were the safety, tolerability and pharmacokinetics (PK) of VRC01 intravenous (i.v.) infusion at 5, 20 or 40 mg/kg, given either once (20 mg/kg) or twice 28 days apart (all doses), and of subcutaneous (s.c.) delivery at 5 mg/kg compared to s.c. placebo given twice, 28 days apart. Cumulatively, 28 subjects received 43 VRC01 and nine received placebo administrations. There were no serious adverse events or dose-limiting toxicities. Mean 28-day serum trough concentrations after the first infusion were 35 and 57 µg/ml for groups infused with 20 mg/kg (n = 8) and 40 mg/kg (n = 5) doses, respectively. Mean 28-day trough concentrations after the second infusion were 56 and 89 µg/ml for the same two doses. Over the 5-40 mg/kg i.v. dose range (n = 18), the clearance was 0.016 l/h and terminal half-life was 15 days. After infusion VRC01 retained expected neutralizing activity in serum, and anti-VRC01 antibody responses were not detected. The human monoclonal antibody (mAb) VRC01 was well tolerated when delivered i.v. or s.c. The mAb demonstrated expected half-life and pharmacokinetics for a human immunoglobulin G. The safety and PK results support and inform VRC01 dosing schedules for planning HIV-1 prevention efficacy studies.


Subject(s)
Antibodies, Monoclonal , Antibodies, Neutralizing , HIV Antibodies , HIV Infections , HIV-1 , Adolescent , Adult , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal/pharmacokinetics , Antibodies, Neutralizing/administration & dosage , Antibodies, Neutralizing/adverse effects , Broadly Neutralizing Antibodies , Dose-Response Relationship, Drug , Female , HIV Antibodies/administration & dosage , HIV Antibodies/adverse effects , HIV Infections/blood , HIV Infections/drug therapy , Half-Life , Humans , Male , Middle Aged
6.
Am J Obstet Gynecol ; 185(5): 1218-25, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11717660

ABSTRACT

OBJECTIVES: This study was carried out to determine the distribution of maternal-fetal medicine (MFM) subspecialists and to profile MFM subspecialists' (1) target patient populations, (2) practice organization, (3) workloads, (4) services provided, and (5) job satisfaction. STUDY DESIGN: The membership of the Society for Maternal-Fetal Medicine was compared with birth projections for metropolitan statistical areas. A survey was sent to Society for Maternal-Fetal Medicine members. RESULTS: The national supply of MFM subspecialists was 0.34, with individual census regions ranging from 0.22 to 0.52 per thousand births. MFM subspecialists report spending 64% of their time in clinical pursuits, 9% in research, and 12% in administration. They evaluate an average of 512 patients annually and work a 67-hour week (SD, 15.8 hours). Ninety-four percent perform deliveries and 87% perform targeted ultrasound examinations. Overall job satisfaction averages 7.4 on a 10-point scale. CONCLUSION: The data provide useful bench-marking information for MFM subspecialists exploring options for practice and for health care planners and organizations developing staffing plans. Despite changes in the health care system, MFM subspecialists continue to express a positive attitude toward their work.


Subject(s)
Attitude of Health Personnel , Medicine , Obstetrics , Professional Practice , Specialization , Data Collection , Delivery, Obstetric , Female , Humans , Job Satisfaction , Pregnancy , Ultrasonography, Prenatal , Workforce
7.
Matern Child Health J ; 4(1): 7-18, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10941756

ABSTRACT

OBJECTIVE: Infant mortality has been reduced dramatically with the development of perinatal regionalized high-technology care. Our objective was to assess use of high technology care among women with high-risk pregnancies in the urban and rural United States. METHODS: The 1988 National Maternal and Infant Health Survey was linked to the 1988 American Hospital Association survey of all obstetrical hospitals. Hospitals were classified into five levels of care based on services and staffing. Women were classified as having high-risk pregnancies using two definitions: (1) gestational age < 34 weeks and birthweight < 1500 g (High Risk I) and (2) the first definition or an antenatal high-risk medical diagnoses (High Risk II). Analyses assessed the proportion of high-risk women delivering in appropriate locations in the rural and urban United States and explored how personal characteristics, insurance status, and use and source of prenatal care influenced where high-risk women delivered. RESULTS: 71.2% of High Risk I and 55.9% of High Risk II women delivered in a high-technology facility (Level IIA or III). Fifty percent of HRI rural women delivered in tertiary high-technology hospitals and 39% of HRII rural women delivered in a high-technology hospital. High-risk urban women were two to three times more likely to deliver in a high-technology facility compared to their rural counterparts. The multivariate analysis showed that Black high-risk women were more likely to deliver in a high-technology setting and that receipt of prenatal care in a private setting lowered the odds of delivering in a high-technology setting when other factors were controlled. CONCLUSIONS: In an era where regionalized perinatal care was not threatened by managed care, a large proportion of high-risk women received care in less than optimal settings. Rural high-risk women delivered in high-technology hospitals less often than their urban counterparts. The multivariate analyses implied that the potential barriers to care may be more important among those considered more socially advantaged, who may be more at the mercy of managed care. The current reimbursement environment, which discourages referral to specialists and high-technology care, could result in less access today.


Subject(s)
Delivery Rooms/statistics & numerical data , Perinatal Care/organization & administration , Pregnancy, High-Risk , Regional Medical Programs/statistics & numerical data , Technology, High-Cost/statistics & numerical data , Adolescent , Adult , Delivery Rooms/classification , Female , Humans , Infant , Infant Mortality , Infant, Newborn , Multivariate Analysis , Pregnancy , Regional Medical Programs/organization & administration , Surveys and Questionnaires , United States
8.
J Perinatol ; 20(4): 219-24, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10879333

ABSTRACT

OBJECTIVE: To determine whether engaging pregnant substance abusers in an integrated program of prenatal care and substance abuse treatment would improve neonatal outcomes. STUDY DESIGN: The subjects were women who voluntarily enrolled in Project Link, an intensive outpatient substance abuse treatment program at Women and Infants Hospital, Providence, RI. A total of 87 women received substance abuse treatment in conjunction with their prenatal care; the comparison group of 87 women received equivalent prenatal care but did not enroll in the substance abuse treatment program until after they delivered. The two groups of women were similar demographically and socioeconomically and had similar substance abuse histories. Univariate and multivariate analyses were performed. The key outcomes were gestational age at delivery, birth weight, preterm delivery, Apgar scores, and neonatal intensive care admission rate. Factors controlled in the multivariate models included demographics, socioeconomic status, parity, and prenatal care. RESULTS: Infants born to women who enrolled prenatally were 400 gm heavier (p < 0.001), and their gestational age was 2 weeks longer (p < 0.001) than infants of mothers enrolled postpartum. In addition, they were approximately one-third as likely to be born with a low birth weight (p < 0.01) and approximately one-half as likely to be admitted to the neonatal intensive care unit (p < 0.05). CONCLUSION: Neonatal outcome is significantly improved for infants born to substance abusers who receive substance abuse treatment concurrent with prenatal care compared with infants born to substance abusers who enter treatment postpartum.


Subject(s)
Pregnancy Complications/prevention & control , Pregnancy Outcome , Prenatal Care/methods , Substance-Related Disorders/therapy , Adolescent , Adult , Female , Humans , Logistic Models , Multivariate Analysis , Postnatal Care/methods , Pregnancy , Prognosis , Risk Assessment , Socioeconomic Factors , Treatment Outcome
9.
Memory ; 8(6): 393-400, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11145070

ABSTRACT

When subjects study lists of thematically related words they sometimes falsely recognise non-presented words related to the theme. The gist extraction account of these findings provided by fuzzy trace theory suggests that false recognition should decline substantially more slowly than true recognition across a delay. In two experiments we demonstrated that corrected recognition of targets and critical lures can decrease by equivalent amounts across a 48-hour delay. However the results for uncorrected recognition were mixed. In Experiment 1 we found evidence that uncorrected recognition of targets declined more rapidly than uncorrected recognition of critical lures. In Experiment 2, we found evidence that uncorrected recognition of targets and critical lures declined at equivalent rates. Results are discussed in terms of their implications for fuzzy trace and source monitoring accounts of false memories.


Subject(s)
Memory , Adult , Humans , Mental Recall , Models, Psychological , Time Factors
10.
J Perinatol ; 20(8 Pt 1): 520-9, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11190593

ABSTRACT

OBJECTIVE: This report explores the availability of neonatal special care services in the US and examines the variation in those services from both the staffing and service perspectives. STUDY DESIGN: The American Hospital Association survey of hospitals and a special national survey of hospitals with special care services were used as data sources to describe changes in the status of high-risk care between 1983 and 1997. The latter survey had a 69% response rate and was a collaborative effort among the March of Dimes, the Maternal and Child Health Bureau, the American Hospital Association, the American Academy of Pediatrics, the American College of Obstetricians and Gynecologists, Ross Labs, and the National Perinatal Information Center (NPIC). RESULTS: The study found that across all regions of the US, the special care supply has expanded. However, the study shows wide variation in medical staffing even among those hospitals offering the most intensive services; 25% had no physician in-house coverage 24 hr/d. CONCLUSION: There is wide availability of high-risk newborn care which is a possible oversupply; however, differential physician staffing raises issues regarding the need for more standardized care.


Subject(s)
Health Services Accessibility , Intensive Care Units, Neonatal/statistics & numerical data , Intensive Care, Neonatal/statistics & numerical data , Humans , Infant, Newborn , Intensive Care, Neonatal/trends , United States , Workforce
11.
Pediatrics ; 103(1 Suppl E): 291-301, 1999 Jan.
Article in English | MEDLINE | ID: mdl-9917472

ABSTRACT

This article discusses the use of administrative data for quality improvement in perinatal and neonatal medicine. We review the nature of administrative data and focus on hospital discharge abstract data as the primary source of hospital- and community-based assessments. Although discharge abstract data lack the richness of primary data, these data are the most accessible comparative data source for examining all patients admitted to a hospital. When aggregated to the state level as occurs in more than 30 states, hospital discharge data reflects hospital utilization and outcomes for an entire geographic population at the state and community level. This article reviews some of the weaknesses of administrative data and then focuses how these data can be used for hospital- and community-based assessment of perinatal care citing as examples the measures of perinatal process and outcome used by the National Perinatal Information Center in its Quality/Efficiency Reports for member hospitals and a study of perinatal high-risk care in the State of Florida. The use of discharge abstract data for performance measurement at either the hospital or the system level requires a thorough understanding of how to select a patient group, its characteristics, the intervention, and the outcomes relevant to that patient group. In the perinatal arena, the National Perinatal Information Center has selected and presents those measures that rely on data items shown to be the most reliable based on validity studies and clinician opinion, delineation of the intervention, and the measurement of what occurred. As hospitals respond to the recent pressures of the Joint Commission on Accreditation of Healthcare Organizations and other quality assurance entities, the accuracy of the discharge data will improve. With accepted caution, these data sets are invaluable to researchers studying comparative populations over time or across large geographic areas.


Subject(s)
Databases, Factual , Neonatology/standards , Outcome and Process Assessment, Health Care/methods , Patient Discharge/statistics & numerical data , Perinatology/standards , Quality Assurance, Health Care , Birth Weight , Diagnosis-Related Groups , Hospital Records , Humans , Insurance Claim Review/statistics & numerical data , Neonatology/statistics & numerical data , Perinatology/statistics & numerical data , Population Surveillance , Total Quality Management , United States
12.
JAMA ; 281(1): 46-52, 1999 Jan 06.
Article in English | MEDLINE | ID: mdl-9892450

ABSTRACT

CONTEXT: Antenatal corticosteroids for fetal maturation have been underused, despite evidence for their benefits in cases of preterm birth. OBJECTIVE: To evaluate dissemination strategies aimed at increasing appropriate use of this therapy. DESIGN AND SETTING: Twenty-seven tertiary care institutions were randomly assigned to either usual dissemination of practice recommendations (n = 14) or usual dissemination plus an active, focused dissemination effort (n = 13). SUBJECTS: Obstetricians and their preterm delivery cases at participating hospitals. INTERVENTION: Recommendations by a National Institutes of Health (NIH) Consensus Conference held in late February-early March 1994 were disseminated in early May 1994. Usual dissemination was publication of the recommendations and endorsement by the American College of Obstetricians and Gynecologists. Active dissemination was a year-long educational effort led by an influential physician and a nurse coordinator at each facility, consisting of grand rounds, a chart reminder system, group discussion of case scenarios, monitoring, and feedback. MAIN OUTCOME MEASURE: Use or nonuse of antenatal corticosteroids was abstracted from medical records of eligible women delivering at the participating hospitals in the 12 months immediately prior to release of the NIH recommendations (average number of records abstracted, 130) and in the 12 months following their release (average number of records abstracted, 122). RESULTS: Active dissemination significantly increased the odds of corticosteroid use after the conference. Use increased from 33.0% of eligible patients receiving corticosteroids to 57.6%, or by 75% over baseline, in usual dissemination hospitals. Use increased from 32.9% to 68.3%, oran 108% increase, in active dissemination hospitals. Gestational age and maternal diagnosis affected use of the therapy in complex ways. CONCLUSION: An active, focused dissemination effort increased the effectiveness of usual dissemination methods when combined with key principles to change physician practices.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , Betamethasone/therapeutic use , Dexamethasone/therapeutic use , Glucocorticoids/therapeutic use , Guideline Adherence , Infant, Premature, Diseases/prevention & control , Obstetric Labor, Premature/prevention & control , Practice Guidelines as Topic , Pregnancy, High-Risk , Anti-Inflammatory Agents/administration & dosage , Betamethasone/administration & dosage , Consensus Development Conferences, NIH as Topic , Dexamethasone/administration & dosage , Drug Utilization , Embryonic and Fetal Development , Female , Gestational Age , Glucocorticoids/administration & dosage , Humans , Infant, Newborn , Infant, Premature , Obstetric Labor Complications/prevention & control , Pregnancy , United States
13.
Pediatr Clin North Am ; 45(3): 635-50, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9653442

ABSTRACT

In the era of managed care, the potential for high-risk patients of all ages to receive less than optimal care exists because the mechanism for reimbursement is designed to promote savings. The specific ways managed care payment mechanisms actually differ from indemnity insurance or fee-for-service are conceptually quite simple. This article reviews mechanisms such as utilization review, setting length-of-stay bench marks, preapproval for referrals to specialists, specific treatments, procedures, and hospital days.


Subject(s)
Health Maintenance Organizations/standards , Hospital Mortality , Intensive Care Units, Neonatal/standards , Intensive Care, Neonatal/standards , Medicaid/standards , Pulmonary Surfactants/therapeutic use , Critical Illness/economics , Critical Illness/therapy , Female , Florida , Health Maintenance Organizations/economics , Humans , Infant, Newborn , Intensive Care Units, Neonatal/economics , Intensive Care, Neonatal/economics , Male , Medicaid/economics , Odds Ratio , Quality of Health Care , Racial Groups , United States
14.
J Consult Clin Psychol ; 65(6): 970-83, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9420358

ABSTRACT

Psychological therapy based on cognitive science advances as psychological states can be precisely measured. This article describes a treatment approach, personal quality improvement (PQI), that draws on (a) the states of mind (SOM) model, a mathematical model built on cognitive assessment research on the balance of positive and negative thoughts and feelings; (b) total quality control, a method for improving quality as defined by increased system stability by empowering average workers to reduce variability through process monitoring; and (c) the phase model of psychotherapy, a framework that proposes 3 distinct stages of treatment. In a single-case study, a depressed client used PQI to track emotional, self-image, and optimism balance, achieving an improvement trajectory consistent with the SOM and phase models. PQI emphasizes process, uses a patient focused treatment paradigm that provides tools for autonomous functioning, and allows for calibration of psychological measures.


Subject(s)
Cognitive Behavioral Therapy , Cognitive Science , Quality Assurance, Health Care , Adult , Depressive Disorder/diagnosis , Depressive Disorder/psychology , Depressive Disorder/therapy , Humans , Male , Motivation , Neurobehavioral Manifestations , Personality Assessment/statistics & numerical data , Psychometrics , Quality of Life , Self Concept
15.
J Perinatol ; 16(6): 483-9, 1996.
Article in English | MEDLINE | ID: mdl-8979190

ABSTRACT

OBJECTIVE: Access to high-risk newborn care is determined by supply of services, demand, and financing. Major changes in health care have occurred since the advent of perinatal regionalization in the mid-1970s. This article explores access from the point of view of the supply and demand for neonatal intensive care within the changing financing environment. STUDY DESIGN: An analysis was done of the 1983, 1989, and 1991 American Hospital Association survey data, combined with birth data from the National Center for Health Statistics. RESULTS: By 1991 supply of hospital-based high-risk newborn care exceeded demand; nationally, there were roughly 300,000 excess bed-days available in 1991. Regional figures revealed that these estimates are, if anything, conservative. CONCLUSIONS: Payers are increasingly price sensitive and have the ability to shift blocks of patients from one facility to another. A surplus encourages a shift of patients to low-price locations. Differentiation of quality and monitoring will become an important means of ensuring access to high-quality care in a surplus environment.


Subject(s)
Health Services Needs and Demand/trends , Intensive Care Units, Neonatal/supply & distribution , Intensive Care Units, Neonatal/statistics & numerical data , Bed Occupancy/statistics & numerical data , Health Care Surveys , Health Services Accessibility , Health Services Needs and Demand/statistics & numerical data , Humans , Infant, Newborn , Intensive Care Units, Neonatal/economics , Intensive Care, Neonatal/trends , Medicaid , Medicare , Patient Transfer , Reimbursement Mechanisms , South Carolina , United States
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