scholarly journals Cranberry derivatives enhance biofilm formation and transiently impair swarming motility of the uropathogenProteus mirabilisHI4320

2016 ◽  
Vol 62 (6) ◽  
pp. 464-474 ◽  
Author(s):  
Che O’May ◽  
Olivier Amzallag ◽  
Karim Bechir ◽  
Nathalie Tufenkji
Keyword(s):  
Biofilm Formation ◽  
Urease Activity ◽  
Lysogeny Broth ◽  
Medium Ph ◽  
Swarming Motility ◽  
Indirect Indicator ◽  
Time Periods ◽  
Bull's Eye ◽  
Short Time

Proteus mirabilis is a major cause of catheter-associated urinary tract infection (CAUTI), emphasizing that novel strategies for targeting this bacterium are needed. Potential targets are P. mirabilis surface-associated swarming motility and the propensity of these bacteria to form biofilms that may lead to catheter blockage. We previously showed that the addition of cranberry powder (CP) to lysogeny broth (LB) medium resulted in impaired P. mirabilis swarming motility over short time periods (up to 16 h). Herein, we significantly expanded on those findings by exploring (i) the effects of cranberry derivatives on biofilm formation of P. mirabilis, (ii) whether swarming inhibition occurred transiently or over longer periods more relevant to real infections (∼3 days), (iii) whether swarming was also blocked by commercially available cranberry juices, (iv) whether CP or cranberry juices exhibited effects under natural urine conditions, and (v) the effects of cranberry on medium pH, which is an indirect indicator of urease activity. At short time scales (24 h), CP and commercially available pure cranberry juice impaired swarming motility and repelled actively swarming bacteria in LB medium. Over longer time periods more representative of infections (∼3 days), the capacity of the cranberry material to impair swarming diminished and bacteria would start to migrate across the surface, albeit by exhibiting a different motility phenotype to the regular “bull’s-eye” swarming phenotype of P. mirabilis. This bacterium did not swarm on urine agar or LB agar supplemented with urea, suggesting that any potential application of anti-swarming compounds may be better suited to settings external to the urine environment. Anti-swarming effects were confounded by the ability of cranberry products to enhance biofilm formation in both LB and urine conditions. These findings provide key insights into the long-term strategy of targeting P. mirabilis CAUTIs.

scholarly journals A revised approach to the ƒ<i>o</i>F2 long-term trends analysis

2002 ◽  
Vol 20 (10) ◽  
pp. 1663-1675 ◽  
Author(s):  
A. V. Mikhailov ◽  
D. Marin ◽  
T. Yu. Leschinskaya ◽  
M. Herraiz
Keyword(s):  
Geomagnetic Activity ◽  
Practical Importance ◽  
Ionospheric Disturbances ◽  
Activity Increase ◽  
New Approach ◽  
Long Term Trends ◽  
Time Periods ◽  
Short Time ◽  
Long Term Variations

Abstract. A new approach to extract foF2 long-term trends, which are free to a great extent from solar and geomagnetic activity effects, has been proposed. These trends are insensitive to the phase (increasing/decreasing) of geomagnetic activity, with long-term variations being small and insignificant for such relatively short time periods. A small but significant residual foF2 trend, with the slope Kr = - 2.2 × 10-4 per year, was obtained over a 55-year period (the longest avail-able) of observations at Slough. Such small trends have no practical importance. On the other hand, negative (although insignificant) residual trends obtained at 10 ionosonde stations for shorter periods (31 years) may be considered as a manifestation of a very long-term geomagnetic activity increase which did take place during the 20th century. All of the revealed foF2 long-term variations (trends) are shown to have a natural origin related to long-term variations in solar and geomagnetic activity. There is no indication of any manmade foF2 trends.  Key words. Ionosphere (ionosphere-atmosphere interactions, ionospheric disturbances)

scholarly journals Assessment of the Impact of Accelerated Migration Testing for Coated Food Cans Using Food Simulants

Molecules ◽  
2019 ◽  
Vol 24 (17) ◽  
pp. 3123 ◽  
Author(s):  
Rafael Paseiro-Cerrato ◽  
Lowri DeJager ◽  
Timothy H. Begley
Keyword(s):  
Epoxy Resins ◽  
Migration Test ◽  
Food Simulants ◽  
Wide Range ◽  
Time Periods ◽  
Short Time ◽  
Storage Times ◽  
The Impact ◽  
Migration Testing

In this study, an accelerated migration test on food can coatings into food simulants was investigated. Food simulants covering a wide range of polarity were used to conduct migration tests at 60 °C with storage times ranging from 4 h to 30 days. Epoxy-resins, acrylic–phenolic, polyester, and vinyl coatings were exposed to water, 3% acetic acid, 50% ethanol, and Miglyol 812®. Using liquid chromatography coupled to a variety of detectors (UHPLC-Q-Orbitrap-MS, UFLC-MS/MS, and HPLC-DAD), migration of several monomers and previously identified oligomers, as well as some unidentified migrants, were determined during the experiment. The data from this study was compared to our findings from previous long-term migration studies with storage times ranging from 24 h to 540 days at 40 °C using the same can coating applications. The results illustrate that performing migration experiments for short time periods at 60 °C may mimic migration results that would be obtained at 40 °C after long-term migration tests (up to 1.5 years) from food can coatings into food simulants.

Markets, Technological Change and Economic Growth (The Quaid-i-Azam Lecture)

1994 ◽  
Vol 33 (4I) ◽  
pp. 327-356 ◽  
Author(s):  
Richard G. Lipsey
Keyword(s):  
United States ◽  
Economic Growth ◽  
Developing Countries ◽  
Common Ground ◽  
The United States ◽  
Industrial Countries ◽  
Canadian Institute ◽  
Primary Focus ◽  
Short Time

I am honoured to be invited to give this lecture before so distinguished an audience of development economists. For the last 21/2 years I have been director of a project financed by the Canadian Institute for Advanced Research and composed of a group of scholars from Canada, the United States, and Israel.I Our brief is to study the determinants of long term economic growth. Although our primary focus is on advanced industrial countries such as my own, some of us have come to the conclusion that there is more common ground between developed and developing countries than we might have first thought. I am, however, no expert on development economics so I must let you decide how much of what I say is applicable to economies such as your own. Today, I will discuss some of the grand themes that have arisen in my studies with our group. In the short time available, I can only allude to how these themes are rooted in our more detailed studies. In doing this, I must hasten to add that I speak for myself alone; our group has no corporate view other than the sum of our individual, and very individualistic, views.

The Spread of Pollutants from Harbour Sludge Depots

1984 ◽  
Vol 16 (3-4) ◽  
pp. 623-633
Author(s):  
M Loxham ◽  
F Weststrate
Keyword(s):  
Time Scales ◽  
Molecular Diffusion ◽  
Near Field ◽  
Parameter Analysis ◽  
Migration Patterns ◽  
Long Time ◽  
Dilution Effects ◽  
Short Time ◽  
Harbour Sludge

It is generally agreed that both the landfill option, or the civil techniques option for the final disposal of contaminated harbour sludge involves the isolation of the sludge from the environment. For short time scales, engineered barriers such as a bentonite screen, plastic sheets, pumping strategies etc. can be used. However for long time scales the effectiveness of such measures cannot be counted upon. It is thus necessary to be able to predict the long term environmenttal spread of contaminants from a mature landfill. A model is presented that considers diffusion and adsorption in the landfill site and convection and adsorption in the underlaying aquifer. From a parameter analysis starting form practical values it is shown that the adsorption behaviour and the molecular diffusion coefficient of the sludge, are the key parameters involved in the near field. The dilution effects of the far field migration patterns are also illustrated.

scholarly journals Surface Immobilization of Nano-Silver on Polymeric Medical Devices to Prevent Bacterial Biofilm Formation

Pathogens ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 93 ◽  
Author(s):  
Riau ◽  
Aung ◽  
Setiawan ◽  
Yang ◽  
Yam ◽  
...  
Keyword(s):  
Medical Devices ◽  
Biofilm Formation ◽  
Culture Media ◽  
Silver Ions ◽  
Bacterial Biofilm ◽  
Surface Immobilization ◽  
Nano Silver ◽  
Gram Positive Bacteria ◽  
Tissue Microenvironment

: Bacterial biofilm on medical devices is difficult to eradicate. Many have capitalized the anti-infective capability of silver ions (Ag+) by incorporating nano-silver (nAg) in a biodegradable coating, which is then laid on polymeric medical devices. However, such coating can be subjected to premature dissolution, particularly in harsh diseased tissue microenvironment, leading to rapid nAg clearance. It stands to reason that impregnating nAg directly onto the device, at the surface, is a more ideal solution. We tested this concept for a corneal prosthesis by immobilizing nAg and nano-hydroxyapatite (nHAp) on poly(methyl methacrylate), and tested its biocompatibility with human stromal cells and antimicrobial performance against biofilm-forming pathogens, Pseudomonas aeruginosa and Staphylococcus aureus. Three different dual-functionalized substrates—high Ag (referred to as 75:25 HAp:Ag); intermediate Ag (95:5 HAp:Ag); and low Ag (99:1 HAp:Ag) were studied. The 75:25 HAp:Ag was effective in inhibiting biofilm formation, but was cytotoxic. The 95:5 HAp:Ag showed the best selectivity among the three substrates; it prevented biofilm formation of both pathogens and had excellent biocompatibility. The coating was also effective in eliminating non-adherent bacteria in the culture media. However, a 28-day incubation in artificial tear fluid revealed a ~40% reduction in Ag+ release, compared to freshly-coated substrates. The reduction affected the inhibition of S. aureus growth, but not the P. aeruginosa. Our findings suggest that Ag+ released from surface-immobilized nAg diminishes over time and becomes less effective in suppressing biofilm formation of Gram-positive bacteria, such as S. aureus. This advocates the coating, more as a protection against perioperative and early postoperative infections, and less as a long-term preventive solution.

scholarly journals A 20-Year Follow-Up Study of Objectively Measured Physical Activity

2021 ◽  
Vol 18 (6) ◽  
pp. 3076
Author(s):  
Anders Raustorp ◽  
Andreas Fröberg
Keyword(s):  
Physical Activity ◽  
Early Adolescence ◽  
Total Sample ◽  
Short Time Span ◽  
Steps Per Day ◽  
Objectively Measured ◽  
Short Time ◽  
Objectively Measured Physical Activity

Background: The objectives of this study were to explore the effect of time, long-term tracking, and the proportion of objectively measured physical activity (PA) from early adolescence to the mid-thirties. Methods: PA was measured as mean steps per day (SPD) with pedometers during 2000 (T1), 2003 (T2), 2005 (T3), 2010 (T4), 2016 (T5) and 2020 (T6). Data from 64 participants (n = 32 males) were analysed from their early adolescence (T1) to their mid-thirties (T6). Results: SPD decreased in the total sample and among males and females (all, p < 0.001). Males took more mean SPD than females during T1 (p = 0.002), whereas females took more mean SPD during T2 (p = 0.009) and T6 (p = 0.008). Males’ mean SPD tracked between T1 and T2 (p = 0.021), T2 and T3 (p = 0.030), T3 and T4 (p = 0.015) and T4 and T5 (p = 0.003). Females’ mean SPD tracked between T3 and T4 (p = 0.024) and T5 and T6 (p < 0.001). In the total sample, more mean SPD were found on weekdays compared to weekend days at T3 (p = 0.017) and T5 (p < 0.001). Conclusions: SPD decreased between T1 and T6. Mean SPD tracked low-to-moderate in the short time span. From late adolescence to the mid-thirties, more mean SPD was observed during weekdays compared to weekend days.

scholarly journals Inferring Long-Term Demand of Newly Established Stations for Expansion Areas in Bike Sharing System

2021 ◽  
Vol 11 (15) ◽  
pp. 6748
Author(s):  
Hsun-Ping Hsieh ◽  
Fandel Lin ◽  
Jiawei Jiang ◽  
Tzu-Ying Kuo ◽  
Yu-En Chang
Keyword(s):  
New York ◽  
Feature Extraction ◽  
Real World ◽  
Extraction Methods ◽  
Real World Data ◽  
Urban Dynamics ◽  
Bike Sharing ◽  
The Government ◽  
Short Time

Research on flourishing public bike-sharing systems has been widely discussed in recent years. In these studies, many existing works focus on accurately predicting individual stations in a short time. This work, therefore, aims to predict long-term bike rental/drop-off demands at given bike station locations in the expansion areas. The real-world bike stations are mainly built-in batches for expansion areas. To address the problem, we propose LDA (Long-Term Demand Advisor), a framework to estimate the long-term characteristics of newly established stations. In LDA, several engineering strategies are proposed to extract discriminative and representative features for long-term demands. Moreover, for original and newly established stations, we propose several feature extraction methods and an algorithm to model the correlations between urban dynamics and long-term demands. Our work is the first to address the long-term demand of new stations, providing the government with a tool to pre-evaluate the bike flow of new stations before deployment; this can avoid wasting resources such as personnel expense or budget. We evaluate real-world data from New York City’s bike-sharing system, and show that our LDA framework outperforms baseline approaches.

EFFECT OF CORTICOSTEROIDS ON URINARY 5β AND 5α C19 STEROIDS IN MAN

1964 ◽  
Vol 46 (2) ◽  
pp. 197-206 ◽  
Author(s):  
Hildegard Wilson ◽  
Steven Schenker
Keyword(s):  
Testosterone Propionate ◽  
Periodic Fever ◽  
Term Treatment ◽  
Long Term Treatment ◽  
Dexamethasone Therapy ◽  
Normal Women ◽  
Normal Men ◽  
Short Time

ABSTRACT A high proportion of urinary C19 5β to 5α steroid metabolites has been found on administration of glucocorticoids in a number of instances. During long term treatment with prednisone or dexamethasone, 100 mg testosterone propionate was administered to 3 patients. The ratios of the resulting metabolites etiocholanolone (E, 5β) to androsterone (A, 5α) were 2.7, 3.3 and 2.1, compared to 1.3 and 0.9 after withdrawal of corticoids from the first 2 patients. In 3 normal men, ratios of endogenously derived E and A while receiving corticoids, compared to control ratios were 2.3 to 1.0, 2.2 to 0.6 and 1.2 to 0.9. Ratios in normal women rose from 1.1 to 2.2 and 2.4 to 4.3 on receiving dexamethasone. Not all subjects gave the expected response. In 3 of these the dosage of corticoid was either low or given for a short time. The ratio of C19O3 metabolites of administered 11β-hydroxy-androst-4-ene-3,17-dione was also changed in favour of the 5β products during corticoid treatment. In a man with periodic fever the high E/A ratios observed were probably related to dexamethasone therapy rather than to the disease.

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