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Premise of the Study: Most pollen walls are interrupted by apertures, thin areas providing access to stigmatic fluids and exit points for pollen tubes. Unexpectedly, pollen tubes of Arabidopsis thaliana are not obligated to pass through apertures and can instead take the shortest route into the stigma, passing directly through a nonaperturate wall., Methods: We used stains and confocal microscopy to follow early pollen tube formation in A. thaliana and 200+ other species. We germinated pollen in vitro and in situ (at control and high humidities) and also used atomic force microscopy to assay material properties of nonaperture and aperture walls., Key Results: Pollen tubes of A. thaliana breached nonaperture walls despite these being an order of magnitude stiffer than aperture walls. Breakout was associated with localized swelling of the pectin-rich (alcian blue positive) intine. The precision of pollen tube exit at the pollen-stigma interface was lost at high humidity. Pollen from ∼4% of the species surveyed exhibited breakout germination behavior; all nine breakout species identified so far are in the Brassicaceae family (∼25% of the Brassicaceae sampled) and are scattered across seven tribes., Conclusions: The polarity of pollen germination in A. thaliana is externally induced, not linked to aperture location. The biomechanical force for breaking nonaperture walls is found in localized swelling of intine pectins. As such, the pollen from A. thaliana, and likely many Brassicaceae family members, are functionally omniaperturate. This new mechanism for germination between extant apertures raises questions about exine porosity and the diversity of mechanisms across taxa., (© 2016 Botanical Society of America.)

The everyday world of clinical practice is filled with paradigms and paradoxes that stem from the issues of who defines knowledge, how it is generated, and how the individual midwife applies it when providing care for women and families. Research useful for clinical practice should provide evidence to support scientific approaches (models) or strategies (interventions) in caring for women. In a clinical discipline, the answers to research questions should eventually inform clinical decision-making by providing practical clinical knowledge. This article presents an application of Stevenson's research steps for the development of clinically applicable knowledge that the midwife can use to analyze and evaluate research findings as a basis for practice decisions. Specific examples of midwifery research are used to illustrate each stage in the process and the circular nature of knowledge development. The challenge is to prepare midwives who can apply research findings skillfully using the best evidence to support clinical practice, as well as to groom midwife researchers who will develop systematic programs of relevant research about midwifery practice and outcomes.

The efficacy and pharmacokinetic profiles of two oral formulations of cyclosporine A (Sandimmune and Neoral; Sandoz Pharmaceuticals, East Hanover, NJ) were evaluated in 37 patients with moderate to severe plaque psoriasis in a randomized, double-blind, modified, crossover study. Cyclosporine A (150 mg twice daily), administered in either formulation, reduced the severity of plaque lesions: 94% of all patients reported at least moderate improvement and 70% reported complete clearing. Approximately 2 weeks of therapy were required for drug exposure to stabilize on either formulation. Cyclosporine A exposure from Neoral was significantly greater relative to that from Sandimmune across all study weeks. At the eighth week (before crossover), AUC and Cmax values for Neoral and Sandimmune were 5618 +/- 1705 versus 3202 +/- 596 ng.h/mL and 1283 +/- 337 versus 623 +/- 173 ng/mL, respectively. In crossover analysis at steady state, the relative oral bioavailability of cyclosporine from the Neoral formulation was 54% greater than that from Sandimmune. Some pharmacokinetic parameters showed less variability both between and within groups of patients taking Neoral versus Sandimmune. Both formulations were well tolerated, in that most adverse events were of mild severity.

Quinolone antimicrobials absorb ultraviolet radiation and, with appropriate drug concentrations, may cause photoreactions. Photoreactions have been reported for several quinolones, including lomefloxacin, a difluorinated quinolone antimicrobial. This study was designed to determine whether the interval between administration of lomefloxacin and exposure to ultraviolet A (UVA) light would affect skin responses. The minimal erythema dose (MED) and severity of local reactions were the main parameters of evaluation. Exposure to UVA radiation 2 hours after morning dosing caused an increase in skin sensitivity as assessed by changes in MED (p < 0.05). No changes were observed with exposure 16 hours after evening dosing (p = 1.00). Edema and blisters at the radiation sites were observed in only the morning dosing group. A significant negative correlation was observed between lomefloxacin plasma concentrations and change MEDs (r = -0.72; p < 0.05). An evening dosing strategy may minimize the risk of phototoxic effects.

The Childbirth Self-Efficacy Inventory (CBSEI) is a self-report instrument that measures outcome expectancies and self-efficacy expectancies for coping with an approaching childbirth experience. The CBSEI scales have excellent internal consistency reliability (.86 to .96) and factor analysis suggested that each CBSEI scale is unidimensional. Validity of the CBSEI was supported by significant positive correlations with the criterion variables of generalized self-efficacy, self-esteem, and internal health locus of control; and significant negative correlations with external health locus of control and learned helplessness. Validity was also supported by significantly higher self-efficacy scores for multiparous as compared to nulliparous pregnant women.

While it is not an innovation in the more established social sciences, the multitrait multimethod (MTMM) technique (Campbell & Fiske, 1959) and additional, more powerful statistical methods of interpreting a MTMM matrix of correlations, have not been used extensively in nursing to assess construct validity of new instruments. This article reviews the Campbell and Fiske method for the assessment of convergent and discriminant validity, reviews the application of the method in the nursing literature, and describes the limitations of the original method. In addition, the procedures, strengths, and limitations of the analysis of variance and confirmatory factor analytic approaches to the quantification of Campbell and Fiske's criteria are described.

Visual analogue scales (VAS) have been used in the social and behavioral sciences to measure a variety of subjective phenomena. The VAS method has potential utility for the measurement of a variety of clinical phenomena of interest to nurse investigators. In this review a description of the various forms of the VAS and an historical overview of their development are presented. In addition, conceptual, psychometric, and statistical aspects of the VAS are considered. Finally, strengths and limitations of the VAS method are addressed.

This non-experimental study was designed to investigate the congruence between in-labor report and postpartum recall of labor pain as measured by the McGill Pain Questionnaire (MPQ). Fifty married parturients, ages 19 to 39 at term with a normal pregnancy, served as subjects. Analysis of variance showed that postpartum report of labor pain on the Present Pain Intensity scale of the MPQ was not consistently congruent with pain reported during labor. In contrast, the Pain Rating Index of the MPQ provided postpartum data that was congruent with the in-labor report. Significant interaction effects, however, suggested that postpartially the women tended to devaluate the pain of early labor and inflate the pain of transitional labor when compared to their in-labor report. Theoretical and practical implications of the results for the measurement of labor pain are discussed.

This study was designed to investigate the relationships between the perception of pain during active labor and nine predictor variables: age, parity, childbirth preparation, state anxiety, confidence in ability to handle labor, concern regarding the outcome of labor, fear of pain, cervical dilatation and frequency of uterine contractions. The sample included 134 low-risk women at term with a normal singleton pregnancy. Standard and stepwise regression was used to examine the ability of the selected variables to explain the variance in the sensory, affective, and evaluative components of pain as measured by the subscales of the Pain Rating Index of the McGill Pain Questionnaire. Although significant proportions of variance were explained for each component of pain, the study variables were most powerful in their ability to explain the variance in the affective component of active labor pain. The stepwise analysis suggested that of the nine variables, confidence in ability to handle labor was the most significant predictor of all components of pain during active labor.