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1.
Rev Sci Instrum ; 83(4): 045110, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22559579

ABSTRACT

We present the development and characterization of a dedicated resonant soft x-ray scattering facility. Capable of operation over a wide energy range, the beamline and endstation are primarily used for scattering from soft matter systems around the carbon K-edge (∼285 eV). We describe the specialized design of the instrument and characteristics of the beamline. Operational characteristics of immediate interest to users such as polarization control, degree of higher harmonic spectral contamination, and detector noise are delineated. Of special interest is the development of a higher harmonic rejection system that improves the spectral purity of the x-ray beam. Special software and a user-friendly interface have been implemented to allow real-time data processing and preliminary data analysis simultaneous with data acquisition.

2.
Nat Mater ; 11(6): 536-43, 2012 Apr 15.
Article in English | MEDLINE | ID: mdl-22504534

ABSTRACT

Molecular orientation critically influences the mechanical, chemical, optical and electronic properties of organic materials. So far, molecular-scale ordering in soft matter could be characterized with X-ray or electron microscopy techniques only if the sample exhibited sufficient crystallinity. Here, we show that the resonant scattering of polarized soft X-rays (P-SoXS) by molecular orbitals is not limited by crystallinity and that it can be used to probe molecular orientation down to size scales of 10 nm. We first apply the technique on highly crystalline small-molecule thin films and subsequently use its high sensitivity to probe the impact of liquid-crystalline ordering on charge mobility in polymeric transistors. P-SoXS also reveals scattering anisotropy in amorphous domains of all-polymer organic solar cells where interfacial interactions pattern orientational alignment in the matrix phase, which probably plays an important role in the photophysics. The energy and q-dependence of the scattering anisotropy allows the identification of the composition and the degree of orientational order in the domains.

3.
J Phys Condens Matter ; 21(29): 296005, 2009 Jul 22.
Article in English | MEDLINE | ID: mdl-21828544

ABSTRACT

Magnetic anisotropy, magnetization reversal and the magnetooptic Kerr effect in Co(x)Mn(y)Ge(z) have been studied over a range of compositions between 0 and 50 at.% of Ge and between 1 and 3 in the Co to Mn atomic ratio, including the Heusler alloy Co(2)MnGe. A strong quadratic magnetooptic Kerr effect has been observed within a narrow region of composition centered around the Co to Mn atomic ratio of 2, which has been used to probe and quantify the magnetic anisotropy and magnetization reversal of the system. The anisotropy is sixfold with a weak uniaxial component, and it exhibits sensitive dependence on composition, especially on the atomic ratio between Co and Mn. The magnetization reversal process is consistent with the single-domain Stoner-Wohlfarth model.

4.
Manag Care ; 9(7): 56-8, 61-2, 2000 Jul.
Article in English | MEDLINE | ID: mdl-18540342

ABSTRACT

Diffusion of Innovations and Opinion Leader theories can be translated into practical applications to improve health care delivery and financial performance by applying them to influence referral patterns and decrease variations in care. Health care organizations can rapidly spread "better practices" to their practicing physicians by understanding the social and communication networks that are naturally developed by those practitioners. Physicians view this diffusion process as promoting autonomy, and as a legitimate approach to adoption of information needed in daily practice.


Subject(s)
Leadership , Models, Theoretical , Practice Patterns, Physicians' , Quality Assurance, Health Care , Diffusion of Innovation , Guidelines as Topic , Humans , Interprofessional Relations , Social Support
5.
Am J Obstet Gynecol ; 175(5): 1286-92, 1996 Nov.
Article in English | MEDLINE | ID: mdl-8942502

ABSTRACT

OBJECTIVE: Our purpose was to determine whether various measures of poor psychosocial status in pregnancy are associated with spontaneous preterm birth, fetal growth restriction, or low birth weight. STUDY DESIGN: Anxiety, stress, self-esteem, mastery, and depression were assessed at 25 to 29 weeks in 2593 gravid women by use of a 28-item Likert scale. Scores for each psychosocial subscale were determined, and an overall psychosocial score was calculated. Scores were divided into quartiles, and the lowest quartile scores were used to define poor psychosocial status. The percent spontaneous preterm birth, low birth weight, and fetal growth restriction in women with low and high psychosocial scores were compared. Logistic regression analyses provided the odds ratios and 95% confidence intervals. RESULTS: Analyses revealed that stress was significantly associated with spontaneous preterm birth and with low birth weight with odds ratios of 1.16, p = 0.003, and 1.08, p = 0.02, respectively, for each point on the scale. A low score on the combined scale or on any subscale other than stress did not predict spontaneous preterm birth, fetal growth restriction, or low birth weight. After multivariate adjustment was performed for psychosocial status, substance use, and demographic traits, black race was the only variable significantly associated with spontaneous preterm birth, fetal growth restriction, and low birth weight; stress and low education were associated with spontaneous preterm birth and low birth weight. CONCLUSION: Stress was associated with spontaneous preterm birth and low birth weight even after adjustment for maternal demographic and behavioral characteristics. Black race continues to be a significant predictor of spontaneous preterm birth, fetal growth restriction, and low birth weight even after adjustment for stress, substance use, and other demographic factors.


Subject(s)
Obstetric Labor, Premature/etiology , Stress, Psychological/complications , Adult , Birth Weight , Female , Fetal Growth Retardation/etiology , Humans , Infant, Low Birth Weight , Infant, Newborn , Pregnancy , Pregnancy Complications
6.
J Obstet Gynecol Neonatal Nurs ; 25(7): 569-92, 1996 Sep.
Article in English | MEDLINE | ID: mdl-8892127

ABSTRACT

Nursing care is a critical component of therapy for women experiencing preterm labor. Diversity exists, however, in the level of comprehensiveness and consistency in guidelines for clinical practice. Nonstandardized care interferes with the ability to achieve consistent, positive patient care outcomes. This article is intended for nurses who seek to organize and standardize their care for women experiencing preterm labor. This article presents a review of the applicable practice and research literature. Clinical guidelines for the nursing management of women experiencing preterm labor are presented in the appendix.


Subject(s)
Obstetric Labor, Premature/nursing , Patient Care Planning , Practice Guidelines as Topic , Female , Home Care Services , Humans , Mass Screening , Nursing Assessment , Patient Discharge , Pregnancy , Tocolysis/nursing
8.
J Obstet Gynecol Neonatal Nurs ; 23(4): 293-300, 1994 May.
Article in English | MEDLINE | ID: mdl-8057182

ABSTRACT

OBJECTIVE: To compare definitions of comfort held by a group of postpartum substance users with those of a group of nonusers. SETTING: The postpartum unit of a large university hospital. PARTICIPANTS: The convenience sample constituted 36 postpartum women; half were substance users and half denied substance use. The nonusing participants were matched to the users according to age, race, type of delivery, and parity. DESIGN: Qualitative, descriptive. MAIN OUTCOME MEASURES: Data were collected through semistructured, individual interviews. Patients defined comfort and described the characteristics and patterns of comfort during the postpartum period. RESULTS: Data were analyzed into three categories of themes. Attributes of comfort were resolution of pain, resolution of fatigue, satiation of hunger, resolution of individual irritants, and relaxation. Interventions for comfort were standard therapy, supportive presence, and caring nursing approach. Modifiers of comfort were individualized comfort patterns, environmental ease, and maternal concern. CONCLUSIONS: Comfort is more than the absence of pain. A supportive presence and a caring nursing approach were the most helpful interventions.


Subject(s)
Fatigue/psychology , Hunger , Maternal-Child Nursing/methods , Pain/psychology , Patient Satisfaction , Puerperal Disorders/psychology , Relaxation , Substance-Related Disorders/psychology , Adolescent , Adult , Empathy , Fatigue/nursing , Female , Humans , Matched-Pair Analysis , Nurse-Patient Relations , Nursing Methodology Research , Pain/nursing , Puerperal Disorders/nursing , Relaxation/psychology , Sampling Studies , Substance-Related Disorders/nursing
9.
N Z Med J ; 106(969): 514-6, 1993 Dec 08.
Article in English | MEDLINE | ID: mdl-8183490

ABSTRACT

AIM: To determine the incidence of injury deaths and hospitalisations associated with pedal cycle use in both traffic and nontraffic environments and in the national population of New Zealand. METHODS: All cases of pedal cycle injuries resulting in death between 1979-88, and all those resulting in hospitalisation in 1988 were identified from health information services files. RESULTS: Between 1979 and 1988, 238 cyclists died. Seventy-six percent were male, and 39% of all fatalities occurred to those aged 5-14 years. Collisions with motor vehicles accounted for most fatalities. Head injuries alone, or with other injuries, were associated with death in 60% of cases. In 1988, 1500 cyclists were admitted to hospital for the treatment of their injuries. Fifty-one percent of those hospitalised were aged 5-14, and males accounted for 70% of all admissions. Thirty-four percent involved a collision with a motor vehicle. Intracranial injuries and skull fractures accounted for 46% of hospital admissions, and had the highest scores on the abbreviated injury scale (AIS). CONCLUSION: This study shows that head injuries are a common cause of death and hospital admission for cyclists. Increases in cycle helmet wearing rates are likely to reduce the frequency and severity of head injury. Other prevention strategies include cycling skills programmes that have been evaluated and shown to be effective, the identification and modification of aspects of cycle design that contribute to injuries, and changes to road design.


Subject(s)
Accidents, Traffic/statistics & numerical data , Bicycling/injuries , Brain Injuries/epidemiology , Craniocerebral Trauma/epidemiology , Hospitalization/statistics & numerical data , Multiple Trauma/epidemiology , Abbreviated Injury Scale , Accidents, Traffic/mortality , Adolescent , Brain Injuries/mortality , Child , Child, Preschool , Craniocerebral Trauma/mortality , Female , Humans , Incidence , Length of Stay , Male , Multiple Trauma/mortality , Sex Factors
10.
J Prof Nurs ; 9(3): 159-68, 1993.
Article in English | MEDLINE | ID: mdl-8514951

ABSTRACT

The nursing literature is replete with commentary and opinions about the research and scholarly productivity of nursing faculty. There are also a number of research studies on several aspects of faculty productivity. However, a scholarly critique and integration of research on this topic is lacking. This article reviews the literature on faculty research productivity and synthesizes the findings to present recommendations for promoting nursing faculty research and scholarship.


Subject(s)
Faculty, Nursing , Nursing Research , Publishing , Age Factors , Efficiency , Faculty, Nursing/statistics & numerical data , Female , Humans , Interprofessional Relations , Male , Mentors , Organizational Culture , Reinforcement, Psychology , Role , Schools, Nursing/organization & administration
11.
Article in English | MEDLINE | ID: mdl-8220377

ABSTRACT

It frequently is assumed that research is being conducted in an ethical manner. Although this usually is the case, the approaches used to assure an ethical approach are not explicitly described in research proposals, protocols, presentations, or manuscripts. This paper explicates the ethical issues related to conducting clinical nursing research. Ethical principles and the problems of scientific misconduct are presented. Rights of human subjects and rights of special subjects are discussed, and practical points about the conduct of ethical research are summarized.


Subject(s)
Clinical Nursing Research , Ethics, Nursing , Animal Welfare , Animals , Authorship , Child , Child Advocacy , Clinical Nursing Research/standards , Confidentiality , Duplicate Publications as Topic , Fetus , Human Experimentation , Humans , Patient Advocacy , Professional Staff Committees
14.
Endocrinology ; 130(2): 945-53, 1992 Feb.
Article in English | MEDLINE | ID: mdl-1733736

ABSTRACT

The release of pituitary GH appears to be critically dependent on alterations in the free intracellular Ca2+ concentration ([Ca2+]i). However, little is known about the nature of Ca2+ signalling within normal pituitary cells. We, therefore, examined [Ca2+]i patterns in individual cultured pituicytes of adult male rats under basal conditions and in response to GH regulatory agents, using the calcium-sensitive dye fura-2 together with digital imaging microscopy. Perfusion of cultured anterior pituitary cells with GH-releasing factor (GHRF) resulted in a marked increase in [Ca2+]i in specific pituitary cells. These cells did not respond to other hypothalamic secretagogues (GnRH, TRH, or CRF), and there was no evidence of desensitization on repetitive administration of GHRF. Somatotrophs (n = 134) exhibited spontaneous oscillations of [Ca2+]i in the basal state, with considerable heterogeneity of oscillatory patterns among cells. After application of a near-maximal stimulatory dose of GHRF (1 nM), there was a striking 2.2-fold increase in the amplitude of [Ca2+]i oscillations and only a modest increase in their frequency. Forskolin (1 microM) augmented somatotroph [Ca2+]i in patterns similar to those of GHRF. Somatostatin (10 nM) abolished the [Ca2+]i response to GHRF (n = 26); this reflected a marked reduction in the amplitude of [Ca2+]i oscillations and a slight reduction in their frequency. Ca(2+)-free medium or the Ca2+ channel antagonist nimodipine (0.1-1 microM) suppressed the Ca2+ stimulatory effect of GHRF. Conversely, the Ca2+ channel agonist BAY K8644 (1 microM) strikingly augmented the GHRF-induced rise in [Ca2+]i, with a major stimulatory effect on the amplitude of [Ca2+]i oscillations and no observed effect on their frequency. In summary, GHRF and other hypothalamic secretagogues increase [Ca2+]i in pituitary cells in a highly specific manner, consistent with the known specificity of their effects on hormone release. Somatotrophs exhibit spontaneous rhythmic oscillation of [Ca2+]i in the basal state. Known regulators of GH release markedly alter the [Ca2+]i oscillatory pattern in characteristic manners, exerting predominant effects on the amplitude of [Ca2+]i pulses and lesser effects on their frequency. These striking effects of GH regulatory agents on pituitary Ca2+ signalling are consistent with the concept that modulation of [Ca2+]i is a critical mediator of somatotroph function.


Subject(s)
Calcium/metabolism , Growth Hormone-Releasing Hormone/pharmacology , Pituitary Gland, Anterior/physiology , Signal Transduction , Animals , Cells, Cultured , Colforsin/pharmacology , Corticotropin-Releasing Hormone/pharmacology , Cytosol/drug effects , Cytosol/metabolism , Dose-Response Relationship, Drug , Gonadotropin-Releasing Hormone/pharmacology , Kinetics , Pituitary Gland, Anterior/drug effects , Rats , Rats, Inbred Strains , Signal Transduction/drug effects , Thyrotropin-Releasing Hormone/pharmacology
15.
Br J Pharmacol ; 96(2): 301-6, 1989 Feb.
Article in English | MEDLINE | ID: mdl-2466517

ABSTRACT

1. In glycerol-lysed human platelets, prostaglandin D2 (PGD2) and the hydantoin BW245C both activate adenylate cyclase in a biphasic manner. These activations are qualitatively different from those of carbacyclin, iloprost and prostaglandin E2 (PGE2) whose E/[A] curves can be adequately described by rectangular hyperbolae. 2. Prostaglandin E1 (PGE1) had E/[A] curves of slope significantly lower than that expected for a rectangular hyperbolae. 2. Prostaglandin E1 (PGE1) had E/[A] curves of slope significantly lower than that expected for a rectangular hyperbola. 3. The selective PGD2 antagonist BW A868C shifts the first phase of the PGD2 and BW245C E/[A] curves but has no effect on the second phase. 4. Applying a two-receptor model enables a pKB to be derived for BW A868C of 9.11. 5. BW A868C has no effect on carbacyclin, iloprost, prostacyclin, PGE1 and PGE2 at a concentration 1,000 fold that of its KB against PGD2 and BW245C. 6. These results indicate that PGD2 and BW245C are capable of activating adenylate cyclase in human platelets through the DP-receptor and by another mechanism as yet uncharacterized.


Subject(s)
Adenylyl Cyclases/blood , Blood Platelets/drug effects , Hydantoins/antagonists & inhibitors , Hydantoins/pharmacology , Prostaglandin D2/antagonists & inhibitors , Blood Platelets/enzymology , Enzyme Activation/drug effects , Epoprostenol/pharmacology , Humans , Iloprost , In Vitro Techniques , Platelet Aggregation/drug effects , Prostaglandin D2/pharmacology , Receptors, Prostaglandin/drug effects
16.
Clin Nurse Spec ; 3(2): 91-6, 1989.
Article in English | MEDLINE | ID: mdl-2736468

ABSTRACT

Consultation is an integral part of the clinical nurse specialist (CNS) role. Some problems, however, are best resolved by a consultant from outside of the organization. This paper presents a decision-making model for use by CNSs in determining the need for an external consultant. The decision-making model involves two general steps. Each step introduces a series of incumbent questions. In the first step, the nature of the problem is assessed, and questions about the philosophical foundation, theoretical framework, and problem substruction are introduced. In the second step, the requirements for solution of the problem are described, precipitating questions about the consultant role requirements, role functions, and introspection and evaluation. Through systematic questioning about the nature of the problem and the solution requirements, the CNS may make an informed decision regarding the recommendation to employ an external consultant. An overall blueprint for the systematic questioning in this decision-making process is presented.


Subject(s)
Consultants , Decision Making, Organizational , Nurse Clinicians , Attitude , Health Facilities , Humans , Models, Psychological , Problem Solving , Role
18.
J Obstet Gynecol Neonatal Nurs ; 15(5): 412-8, 1986.
Article in English | MEDLINE | ID: mdl-3639932

ABSTRACT

A study was conducted to examine the role of the labor and delivery room nurse as perceived by expectant mothers trained in the Lamaze method of preparation for childbirth (L/RC), expectant mothers not trained in the Lamaze method (RC), and labor and delivery room nurses. All expectant mothers received baseline prenatal education by attending Red Cross Preparation for Parenthood. Perceptions were measured through a Q-sort of 50 items constructed for this study. Each item described a nursing behavior in labor and delivery. Differences between Q-sorts of expectant mothers and labor and delivery room nurses were insignificant. The collected data showed that labor and delivery room nurses were meeting the expectations of expectant mothers, both trained and not trained in the Lamaze method. Perceptions of the nurse's role in labor and delivery differed slightly so that individualization of care is important.


Subject(s)
Delivery, Obstetric , Labor, Obstetric , Obstetric Nursing/methods , Patients/psychology , Role , Adult , Female , Humans , Middle Aged , Natural Childbirth , Patient Education as Topic , Pilot Projects , Pregnancy , Red Cross
19.
J Am Coll Cardiol ; 4(1): 72-9, 1984 Jul.
Article in English | MEDLINE | ID: mdl-6736457

ABSTRACT

Asynchronous motion of left ventricular myocardium during the period of left ventricular isovolumic relaxation has often been observed in patients with coronary artery disease. Detection and quantitation of this abnormality with noninvasive nuclear tracer methods, however, have not yet been reported. Thus, functional images of regional left ventricular time to minimum counts (or volume), computed from gated blood pool image sequences, were analyzed to detect and quantitate myocardial asynchrony during this interval. The method was tested by comparing regional with global time to minimum counts before and after coronary artery occlusion in the awake dog. After occlusion, minimum counts in the ischemic region occurred later in the cardiac cycle than did global minimum counts (average difference 69 +/- 37 ms, p less than 0.001). Before occlusion, however, minimum counts in the same region occurred at the same moment as global minimum counts (average difference 4 +/- 12 ms, NS). Thus, acute ischemia in dogs produces a pronounced asynchrony in myocardial motion during the earliest moments of diastole. The magnitude of this asynchrony (69 ms) probably corresponds to the length of the global isovolumic relaxation period in these animals after occlusion. This method might be useful in detecting and quantitating isovolumic asynchrony in ischemia and changes in this asynchrony with therapy (verapamil therapy, for example).


Subject(s)
Coronary Disease/physiopathology , Heart/diagnostic imaging , Myocardial Contraction , Animals , Coronary Circulation , Coronary Disease/diagnostic imaging , Dogs , Radionuclide Imaging
20.
Exp Brain Res ; 56(2): 389-94, 1984.
Article in English | MEDLINE | ID: mdl-6479273

ABSTRACT

Direct absorbance and bleaching absorbance-difference spectra were obtained using a photon-counting microspectrophotometer from the outer segments of ten blue-sensitive cones of macaque monkeys. The peak wavelength (lambda max) of the direct measurements was 426 +/- 3.4 nm, whereas the lambda max of the bleaching difference was 434 +/- 6.6 nm. We consider these values to be upper and lower bounds since both measurements may be shifted in opposite directions by wavelength-dependent effects. Therefore, the true peak sensitivity must be close to 430 nm.


Subject(s)
Photoreceptor Cells/analysis , Retinal Pigments/analysis , Animals , Macaca fascicularis , Macaca mulatta , Spectrophotometry
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