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Synergistic cranberry juice combinations with natural-borne antimicrobials for the eradication of uropathogenic Escherichia coli biofilm within a short time
No full textUrinary tract infections (UTI), one of the most common diseases in humans, are caused primarily by uropathogenic Escherichia coli (UPEC). Cranberry juice (CB) is a widely known prophylaxis for UTI, but the treatment of CB alone could not effectively eradicate preformed UPEC biofilms. The aim of this study was to develop enforced CB composites within a short time by adding a small quantity of natural borne antimicrobials. UPEC biofilms (initial: 6 center dot 0 log CFU per cm(2)), formed on silicone coupons in artificial urine medium, were exposed to CB (4-8%), caprylic acid (CAR; 0 center dot 025-0 center dot 05%) and thymol (TM; 0 center dot 025-0 center dot 05%) at 37 degrees C for 1 min. Individual treatment of each compound did not show the significant antibacterial effect on UPEC biofilms (P > 0 center dot 05). Otherwise, the survivor counts of biofilms were synergistically reduced with CB containing any of the antimicrobials. For example combined treatment with CB (8%) + CAR (0 center dot 05%) + TM (0 center dot 05%) resulted in a 6 log reduction in UPEC populations in the biofilm (no detectable bacteria remained) with 4 center dot 6 log of synergistic bactericidal effect. The confocal laser scanning microscope images indicated that any composites including TM might result in biofilm detachment from the surface. The present method is cost-effective and more acceptable to consumers as it is based on the synergistic interaction of natural borne antimicrobials. The results of this study could be widely applicable in the functional food, medical and healthcare field. Significance and Impact of the Study Anti-biofilm effect of cranberry juice (CB) has been focused mainly on inhibiting biofilm formation of uropathogenic Escherichia coli (UPEC); however, combined treatment with natural borne antimicrobials derived from coconut oil (caprylic acid) and oregano essential oil (thymol) could synergistically enhance its eradicating activity against biofilms. This study developed novel CB composites showing marked anti-biofilm effects (complete eradication of UPEC biofilms within just 1 min)
What makes bullies and victims in Korean elementary schools?
No full textThe purpose of this study is to explore the predictive factors associated with school bullying and victimization among Korean elementary students. The data gathered from the Korean Children and Youth Panel Survey (KCYPS) was used in the analysis, which involved logit modeling and negative binomial regression modeling of a generalized linear model in deriving the relationships among the student individual characteristics, family background, and school life factors obtained from 2011 6th graders. The major findings can be summarized as follows. First, negative self-esteem was significantly associated with both the experience of bullying and victimization. Second, physical exercise in school were found to reduce both the experience and frequency of bullying. Third, negative family background variables were found to increase the frequency of victimization. Fourth, student commitment to school rules was associated with the frequency of bullying and victimization. This research suggests that a positive increase in student self-esteem, athletic activities, cooperation between school and home, and democratic school rules and execution can serve as positive factors in reducing school bullying and victimization
The tale of a two-tiered city: Community civic structure and spatial inequality in post-Katrina New Orleans
No full textIn this article, I investigate the long-term consequences of community civic structure on postdisaster recovery. Tracing various signs of recovery after Hurricane Katrina, I find that community civic structure is associated with deepening, rather than reducing, spatial inequality in New Orleans and report 3 findings. First, community civic structure contributes far more to repopulating communities on higher ground than low-lying neighborhoods. Second, despite the similar level of civic resources before Katrina, community civic structure has cast different impacts on reducing vulnerabilities across neighborhoods after Katrina. Though a dense civic structure helped attract more resilient populations in high-lying neighborhoods, the opposite happened in low-lying neighborhoods. Finally, community civic structure is associated with the city's racialized geography, concentrating more Whites in the city's safer areas and Black residents in the low-lying communities. These findings raise caution against pursuing community-based resilience as a postdisaster strategy
The Use of Magnetic Resonance Imaging in Planning a Pedicled Perforator Flap for Pressure Sores in the Gluteal Region
No full textPedicled perforator flaps (PPFs) have been widely used to treat pressure sores in the gluteal region. Selection of a reliable perforator is crucial for successful surgical treatment of pressure sores using PPFs. In this study, we evaluate the role of magnetic resonance imaging (MRI) in planning PPF reconstruction of pressure sores in the gluteal region. A retrospective chart review was performed in patients who had undergone these PPF reconstructions and who had received preoperative MRI. Preoperatively, the extent of infection and necrotic tissue was evaluated using MRI, and a reliable perforator was identified, considering the perforator location in relation to the defect, perforator size, and perforator courses. Intraoperatively, the targeted perforator was marked on the skin at the locations measured on the MRI images, and the marked location was confirmed using intraoperative handheld Doppler. Superior gluteal artery, inferior gluteal artery, or parasacral perforators were used for the PPFs. Surgical outcomes were evaluated. A total of 12 PPFs were performed in 12 patients. Superior gluteal artery perforator flaps were performed in 7 patients, inferior gluteal artery perforator flaps were performed in 3 patients, and parasacral perforator flaps were performed in 2 patients. We could identify a reliable perforator on MRI, and it was found at the predicted locations in all cases. There was only one case of partial flap necrosis. There was no recurrence of the pressure sores during the mean follow-up period of 6.7 months (range = 3-15 months). In selected patients with gluteal pressure sores, MRI is a suitable means for not only providing information about disease extent and comorbidities but also for evaluating perforators for PPF reconstructions
Development of a superhydrophobic electrospun poly(vinylidene fluoride) web via plasma etching and water immersion for energy harvesting applications
No full textSmart textiles have been enormously developed recently, but attachment of batteries and low washing resistance are the major challenges in the development of wearable smart textiles. However, piezoelectric materials harvesting energy from mechanical action can be readily integrated with smart textiles and can replace conventional batteries. Therefore, energy harvesters with poly(vinylidene fluoride) (PVDF) were fabricated by the electrospinning process. In addition, simple CF4 plasma etching followed by water immersion of the electrospun PVDF webs resulted in superhydrophobicity, with a water contact angle of 169.8 +/- 1.5 degrees, a water shedding angle of 4.7 +/- 1.8 degrees, and self-cleaning properties. This would decrease the number of washing cycles during use and increase the durability of the smart textile. X-ray photoelectron spectroscopy indicated that metals were co-deposited as etch-resisting masks to fabricate a nanostructure during plasma etching and were removed by water immersion. The piezoelectric performance of the superhydrophobic electrospun PVDF web showed a higher peak-to-peak output voltage of 3.50 V than the untreated electrospun PVDF web (2.86 V). Furthermore, the breathability of the superhydrophobic PVDF web was remarkably higher than those of the PVDF film. Therefore, the new flexible electrospun PVDF web with superhydrophobicity and piezoelectricity has significant potential as energy harvesters in wearable smart textiles
PARN: Pyramidal affine regression networks for dense semantic correspondence
No full textThis paper presents a deep architecture for dense semantic correspondence, called pyramidal affine regression networks (PARN), that estimates locally-varying affine transformation fields across images. To deal with intra-class appearance and shape variations that commonly exist among different instances within the same object category, we leverage a pyramidal model where affine transformation fields are progressively estimated in a coarse-to-fine manner so that the smoothness constraint is naturally imposed within deep networks. PARN estimates residual affine transformations at each level and composes them to estimate final affine transformations. Furthermore, to overcome the limitations of insufficient training data for semantic correspondence, we propose a novel weakly-supervised training scheme that generates progressive supervisions by leveraging a correspondence consistency across image pairs. Our method is fully learnable in an end-to-end manner and does not require quantizing infinite continuous affine transformation fields. To the best of our knowledge, it is the first work that attempts to estimate dense affine transformation fields in a coarse-to-fine manner within deep networks. Experimental results demonstrate that PARN outperforms the state-of-the-art methods for dense semantic correspondence on various benchmarks. © Springer Nature Switzerland AG 2018.Ministry of Science, ICT and Future Plannin
Exceptional pemetrexed sensitivity can predict therapeutic benefit from subsequent chemotherapy in metastatic non-squamous non-small cell lung cancer
No full textPurpose: Based on an exceptionally durable response to pemetrexed observed in some patients with metastatic NSCLC, the predictive value of pemetrexed sensitivity to outcomes of subsequent systemic treatment was investigated. Methods: We retrospectively reviewed the patients with metastatic non-squamous NSCLC treated with pemetrexed monotherapy as their first- or second-line chemotherapy between November 2006 and February 2015. Good (top 5% longest) and poor responders (bottom 12% shortest) were defined according to the duration of pemetrexed maintenance. The first and second post-pemetrexed (PP) systemic treatments were defined as PP1 and PP2 therapies, respectively, to define their progression-free survivals (PFS) as PFS1 and PFS2. Results: In a total of 100 patients, 86% of patients received pemetrexed as their second-line chemotherapy, and 34% were classified as good responders. Good and poor responder groups showed 20.5 months and 0.7 months of the median duration of responses, respectively. PP1 and PP2 therapies were done in 74% and 41.9% of patients after failure to pemetrexed. To our surprise, disease control rate (DCR) was significantly higher in the good responder group than poor responder group (69.6% vs 37.3%, p = 0.010) in patients treated with PP1 therapy, and median PFS1 was also significantly longer (5.2 vs 2.2 months, p < 0.01) regardless of the type of subsequent systemic treatment. Meanwhile, pemetrexed sensitivity did not affect DCR or PFS of patients who received PP2 therapies. Conclusions: Patients who achieved durable response to pemetrexed might obtain greater therapeutic benefits from subsequent systemic treatment in metastatic non-squamous NSCLC without targets, which could potentiate more effective post-pemetrexed treatment strategy. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature
A study on the index and satisfaction of the sharing
No full textThe purpose of this study is to develop a sharing index that can objectively assess sharing and to survey factors influencing satisfaction from sharing using the developed sharing index in order to build a structure of virtuous cycle of sharing activity based on the autonomy and satisfaction of sharing agents. In this study, we conducted a factor analysis to analyze the measuring instrument of sharing, and used the Kaiser-Meyer-Olkin measure and Bartlett's test to test the validity and reliability of the questionnaire used for this study. We also used the Kaiser-Meyer-Olkin measure and Bartlett's test to test the validity of the factor analysis. We used the alpha factor extraction method and the Varimax rotation method to find out latent variables for the questionnaire. We conducted a regression analysis to identify factors influencing satisfaction from sharing. Based on the factor analysis, the sharing index is divided into category, division, and section. Category consists of four areas, including knowledge, attitude, practice, and satisfaction. Also, each area of the category is divided into two areas of division, collectivistic and personal. Each area of the division consists of factors in the areas of section. Collectivistic knowledge factor consists of six factors; personal knowledge factor, three factors; collectivistic attitude factor, seven factors; personal attitude factor, two factors; collectivistic practice factor, three factors; personal practice factor, three factors; collectivistic satisfaction factor, four factors; and pbersonal satisfaction, one factor. Satisfaction from sharing was also identified by dividing the concept into collectivistic and personal satisfaction from sharing. Personal satisfaction from sharing was influenced by personal attitude factor, personal practice factor, and personal knowledge factor; and collectivistic satisfaction, by collectivistic attitude factor and collectivistic awareness factor. It was surveyed that to improve collectivistic satisfaction, it was necessary to form knowledge and attitude not only at the personal level but also at the collectivistic level. Key Words: Sharing, Sharing index, Satisfaction, Regression model. © 2017 International Information Institute
Recent advances in the discovery and combinatorial biosynthesis of microbial 14-membered macrolides and macrolactones
No full textMacrolides, especially 14-membered macrolides, are a valuable group of antibiotics that originate from various microorganisms. In addition to their antibacterial activity, newly discovered 14-membered macrolides exhibit other therapeutic potentials, such as anti-proliferative and anti-protistal activities. Combinatorial biosynthetic approaches will allow us to create structurally diversified macrolide analogs, which are especially important during the emerging post-antibiotic era. This review focuses on recent advances in the discovery of new 14-membered macrolides (also including macrolactones) from microorganisms and the current status of combinatorial biosynthetic approaches, including polyketide synthase (PKS) and post-PKS tailoring pathways, and metabolic engineering for improved production together with heterologous production of 14-membered macrolides. © 2018, Society for Industrial Microbiology and Biotechnology
Optimisation of steam and gas push to prevent water influx from a top-water-bearing area into a vapour chamber
No full textThis paper presents how to produce bitumen efficiently from the reservoir with top-water-bearing zone. The impact of naturally occurring and/or co-injected non-condensable gas on bitumen production is investigated using numerical studies. Non-condensable gas can improve energy efficiency in two ways: reduction of dynamic vacuum effect and blockage of direct contact of steam chamber and top water layer. A strategic operation mitigating the groundwater influx is presented. An artificial neural network (ANN) model adjusts both pressures of steam and non-condensable gas injected as well as the amount of non-condensable gas. The results show the optimised scheme of steam and gas push (SAGP) can improve the energy efficiency of thermal recovery by maintaining the pressure within the steam chamber enough to prevent excessive water influx, not to obstruct steam chamber expansion in early production stage