1,912 research outputs found
Reviews
Successful Instructional Diagrams by Ric Lowe, London, Kogan Page, 1993. ISBN: 0–7494–0711–5
Reviews
Technology‐based Learning Environments: Psychological and Educational Foundations edited by S. Vosniadou, E. De Corte and H. Mandl, volume 137 in NATO ASI Series F (Computer and Systems Sciences), Berlin, Springer‐Verlag, ISBN: 0–387–58253–3, 1994
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Why does early childhood deprivation increase the risk for depression and anxiety in adulthood? A developmental cascade model
Abstract Background: Using data from the English & Romanian Adoptees (ERA) study we recently reported that early time-lmited exposure to severe institutional deprivation is
associated with early onset and persistent neurodevelopmental problems and later
onset emotional problems. Here we examine possible reasons for the late
emergence of emotional problems in this cohort. Our main focus is on testing a
developmental cascade mediated via the functional impact of early-appearing
neurodevelopmental problems on late adolescent functioning. We also explore a
second putative pathway via sensitization to stress. Methods: The ERA study includes 165 Romanian individuals who spent their early lives in grossly depriving institutions and were subsequently adopted into UK
families, along with 52 UK adoptees with no history of deprivation. Age six years
symptoms of neurodevelopmental problems and age 15 anxiety/depression
symptoms were assessed via parental reports. Young adult symptoms of depression
and anxiety were assessed by both parent and self-reports; young adults also
completed measures of stress reactivity , exposure to adverse life events and
functioning in work and interpersonal relationships. Results: The path between early institutional deprivation and adult emotional problems was mediated via the impact of early neurodevelopmental problems on
unemployment and poor friendship functioning during the transition to adulthood.
The findings with regard to early deprivation, later life stress reactivity and emotional
problems were inconclusive.
Conclusions: Our analysis suggests that the risk for adult depression and anxiety following extreme institutional deprivation is explained through the effects of early neurodevelopmental problems on later social and vocational functioning. Future research should more fully examine the role of stress susceptibility in this model
Prospectus, October 5, 1988
https://spark.parkland.edu/prospectus_1988/1023/thumbnail.jp
Spiked Nanostructures Disrupt Fungal Biofilm and Impart Increased Sensitivity to Antifungal Treatment
There is a globally increasing demand for medically implanted devices, partly spurred by an aging population. In parallel, there is a proportionate increase in implant associated infection. Much focus has been directed toward the development of techniques to fabricate nanostructured antimicrobial biomaterials to mitigate infection. The present study investigates the interaction of the fungal pathogen Candida albicans with an antimicrobial surface bearing nanoscale protrusions. C. albicans cells were observed to be affected by cell wall stress, which impeded its ability to switch to a hyphal phenotype. There are significant differences in the expression of C. albicans virulence-associated genes between the untreated and nanostructured surfaces. To determine whether the observed inhibition of C. albicans would also sensitize it to antifungal drugs, a culture is established for 3 days on the nanostructured surface before being treated with the antifungal drug amphotericin B. The drug was able to kill all cells on the nanostructured surface at sub-clinical concentrations, while remaining ineffective against cultures grown on a smooth control surface. These findings may eventually prove to be impactful in the clinic, as clinicians may be able to reduce antifungal drug dosages and minimize the effects of drug associated toxicity
Long-term antibacterial properties of a nanostructured titanium alloy surface: An in vitro study
The demand for joint replacement and other orthopedic surgeries involving titanium implants is continuously increasing; however, 1%–2% of surgeries result in costly and devastating implant associated infections (IAIs). Pseudomonas aeruginosa and Staphylococcus aureus are two common pathogens known to colonise implants, leading to serious complications. Bioinspired surfaces with spike-like nanotopography have previously been shown to kill bacteria upon contact; however, the longer-term potential of such surfaces to prevent or delay biofilm formation is unclear. Hence, we monitored biofilm formation on control and nanostructured titanium disc surfaces over 21 days following inoculation with Pseudomonas aeruginosa and Staphylococcus aureus. We found a consistent 2-log or higher reduction in live bacteria throughout the time course for both bacteria. The biovolume on nanostructured discs was also significantly lower than control discs at all time points for both bacteria. Analysis of the biovolume revealed that for the nanostructured surface, bacteria was killed not just on the surface, but at locations above the surface. Interestingly, pockets of bacterial regrowth on top of the biomass occurred in both bacterial species, however this was more pronounced for S. aureus cultures after 21 days. We found that the nanostructured surface showed antibacterial properties throughout this longitudinal study. To our knowledge this is the first in vitro study to show reduction in the viability of bacterial colonisation on a nanostructured surface over a clinically relevant time frame, providing potential to reduce the likelihood of implant associated infections
Web-based Discussion Forums on Pregnancy Complaints and Maternal Health Literacy in Norway: A Qualitative Study
Background: The Internet is one of the fastest growing information sources for pregnant women and seems to be used across social and economic strata. However, we still lack knowledge on how interaction in Web-based discussion forums influence maternal health literacy, in terms of how pregnant women access, appraise, and apply information to promote and maintain good health. Objective: The aim of this study was to understand how Web-based discussion forums influence maternal health literacy; hence, we explored the role of interactions in Web-based discussion forums among women who experienced health problems during pregnancy. More specifically, we explored why media-literate women experiencing the medically unexplained condition, pelvic girdle pain (PGP), during pregnancy participated in Web-based discussion forums and how they appraised and applied the information and advice that they gained from the Web-based interaction with other women. Methods: Women were invited to participate in the study via postings on 3 different open websites for pregnant women and mothers. The sample included 11 Norwegian women who participated in open Web-based discussion forums when experiencing PGP in pregnancy. The data were collected using synchronous qualitative email interviews and were analyzed using thematic analysis. Results:In our study sample, interaction in Web-based discussion forums influenced maternal health literacy in terms of increased health-related knowledge and competencies, increased awareness of health promotion and health protection, and increased system navigation. The women appraised and selectively applied information and advice that resonated with their own experiences. For many, the information provided online by other women in the same situation was valued more highly than advice from health professionals. Women reported that they used their knowledge and competency in encounters with health professionals but hesitated to disclose the origin of their knowledge. Those with a high level of education in medicine-related fields raised a concern about the Internet as a source of horror stories and erroneous information and were actively engaged in trying to minimize potential negative effects, by providing biomedical information. Conclusions: The popularity of Web-based discussion forums among pregnant women suggests that this group needs additional sources of information and support to complement traditional consultations with the health professionals. The professionals need to recognize that pregnant women access Web-based discussion forums for support and information to increase their ability to take better health decisions for themselves. This is a potential resource that health professionals may find useful in consultations with pregnant women
Bio-Inspired Nanostructured Ti-6Al-4V Alloy: The Role of Two Alkaline Etchants and the Hydrothermal Processing Duration on Antibacterial Activity
Inspired by observations that the natural topography observed on cicada and dragonfly wings may be lethal to bacteria, researchers have sought to reproduce these nanostructures on biomaterials with the goal of reducing implant-associated infections. Titanium and its alloys are widely employed biomaterials with excellent properties but are susceptible to bacterial colonisation. Hydrothermal etching is a simple, cost-effective procedure which fabricates nanoscale protrusions of various dimensions upon titanium, depending on the etching parameters used. We investigated the role of etching time and the choice of cation (sodium and potassium) in the alkaline heat treatment on the topographical, physical, and bactericidal properties of the resulting modified titanium surfaces. Optimal etching times were 4 h for sodium hydroxide (NaOH) and 5 h for potassium hydroxide (KOH). NaOH etching for 4 h produced dense, but somewhat ordered, surface nanofeatures with 75 nanospikes per µm2. In comparison, KOH etching for 5 h resulted sparser but nonetheless disordered surface morphology with only 8 spikes per µm2. The NaOH surface was more effective at eliminating Gram-negative pathogens, while the KOH surface was more effective against the Gram-positive strains. These findings may guide further research and development of bactericidal titanium surfaces which are optimised for the predominant pathogens associated with the intended application
Prospectus, December 15, 1988
https://spark.parkland.edu/prospectus_1988/1032/thumbnail.jp
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