This hypothesis article states that the high relative humidity (RH) of packaged fresh‐cut fruits or vegetables that is associated with spoilage can be used as an advantageous way to deliver ...antimicrobial compounds using cyclodextrins (CDs) as carriers. CDs can function as antimicrobial delivery systems as they can release antioxidant and antimicrobial compounds (guest molecules) as the humidity levels increase in the headspace. Hydrophobic antimicrobial guests can be complexed with CDs due to the amphiphatic nature of the host. Then, at high RH values, due to the water–CDs interaction, host–guest interactions are weakened; consequently, the antimicrobial molecule is released and should protect the product against the microbial growth. Potential antimicrobial compounds capable of forming complexes with CDs are discussed, as well as possible applications to preserve fresh‐cut produce and future research in this area.
Plant foods are rich in phenolic compounds (PCs) that display multifaceted bioactions in health promotion and disease prevention. To exert their bioactivity, they must be delivered to and absorbed in ...the gastrointestinal (GI) tract, transported in circulation, and reach the target tissues. During the journey from ingestion to target tissues and final excretion, PCs are subjected to modifications by many factors during their absorption, deposition, metabolism and excretion (ADME) and consequently their bioefficacy may be modified. Consistent with all nutrients in foods, PCs must first be released from the food matrix through mechanical, chemical, and enzymatic forces to facilitate absorption along the GI tract, particularly in the upper small intestine section. Further, glycosylation of PCs directs the route of their absorption with glycones being transported through active transportation and aglycones through passive diffusion. After enteral absorption, the majority of PCs are extensively transformed by the detoxification system in enterocytes and liver for excretion in bile, feces, and urine. The journey of PCs from consumption to excretion appears to be comparable to many synthetic medications, but with some dissimilarities in their fate and bioactivity after phase I and II metabolism. The overall bioavailability of PCs is determined mainly by chemical characteristics, bioaccessibility, and ADME. In this review, factors accounting for variation in PCs bioavailability are discussed because this information is crucial for validation of the health benefits of PCs and their mechanism of action.
Plant foods are rich in phenolic compounds (PCs) that display multifaceted bioactions in health promotion and disease prevention.
Abstract
The present RPC Link System has been servicing as one of the
CMS subsystems since installation in 2008. Although the current Link
System has been functioning well for the past 13 years, the ...aging of
its electronic components and lack of radiation hard ASICs could
present problems for future operations. Additionally, the needs to
have a more robust control interface against electromagnetic
interference, to improve the trigger performance with finer time
granularity and to incorporate a higher bandwidth transmission lines
led the idea of upgrading the Link System for the HL-LHC. This
paper reviews the features of the recently developed prototype of
the new Link System.
No information is available on roughness and stainability of acrylic resins polymerized by experimental microwave cycles after immersion in stainable liquids and simulated brushing.
The purpose of ...this in vitro study was to evaluate the effect of stainable drinks and brushing on roughness and stainability of acrylic resins (Vipi Cril CA and Vipi Wave MA) polymerized with different cycles.
CA and MA specimens (n=5; diameter, 20 mm; thickness, 3 mm) were made using 4 methods recommended by the manufacturer (water bath polymerization and microwave polymerization cycles) and experimental at 550 W or 650 W for 3 or 5 minutes (M550/3 and M650/5), respectively. After storage in distilled water at 37°C for 48 hours (T0), the specimens were stored in water, coffee, or red wine (37°C) for 36 days with simulated brushing (54 000 cycles, T1). Roughness (Ra) and stainability (ΔE/National Bureau of Standards) were measured at T0 and T1. Roughness and stainability data were analyzed by 3-way repeated measures and 2-way ANOVA, respectively, followed by the Bonferroni test (α=.05).
After storing in coffee and brushing, CA showed the highest (M550/3=2.33 ±0.72 μm) and the lowest roughness (water bath polymerization=1.22 ±0.58 μm), whereas roughness of MA specimens processed by M650/5 increased (1.57 ±0.59 μm). Storing in wine and brushing increased roughness (1.75 ±0.32 μm) in the M550/3 group. No staining was observed on MA after brushing regardless of the polymerization cycle. All values were acceptable (ΔE≤3.3), except for MA (microwave polymerization), which showed National Bureau of Standards=4.49 (appreciable change) after storing in wine and brushing.
A slight increase in material roughness was observed after staining and brushing. Only MA polymerized following manufacturer cycles showed relevant stainability after immersion in wine and brushing.
Thyme essential oil (TO) is a good antimicrobial agent, however, its high volatility and reactivity limits its application as food preservative. β-cyclodextrin (β-CD) is able to encapsulate organic ...molecules, forming host–guest complexes with hydrophobic and volatile molecules such as TO constituents, controlling volatility and reactivity. In addition, controlled released of the β-CD trapped compounds could be possible by exposing the capsules to high relative humidity (RH). With this in mind, the controlled release of antifungal volatiles throughout exposure of TO:β-CD capsules to high relative humidity was studied. Thymol (TOL) was the major constituent of TO, detected by gas chromatography before and after encapsulation. Capsules of the 8:92 ratio (TO:β-CD) showed the highest TOL content. Hydrogen bonds and hydrophobic interactions were detected between the oil constituent and β-CD by IR and
1
H NMR spectroscopy. During moisture sorption, the TO capsules showed a lower water uptake compared with free β-CD. Similar behavior was observed during water desorption. In all cases, a hysteresis process was observed when comparing sorption and desorption isotherms. At high RH, TOL is displaced and almost 76% is released to the headspace. The growth of
Alternaria alternata
was inhibited significantly by the addition and exposure to TO:β-CD as measured by both the agar dilution and the headspace method, respectively. Therefore, the encapsulation of antifungal volatile compounds as TO in β-CD, could be an alternative to control the release of natural antimicrobials that can be of interest to the agricultural area.
Abstract
A new generation of resistive plate chambers, capable of withstanding high particle fluxes (up to 2000 Hz · cm
-2
) and instrumented with precise timing readout electronics is proposed to ...equip two of the four high pseudorapidity stations of the CMS muon system. Double-gap RPC detectors, with each gap made of two 1.4 mm High Pressure Laminate electrodes and separated by a gas gap of the same thickness, are proposed. The new layout reduces the amount of the avalanche charge produced by the passage of a charged particle through the detector. This improves the RPC rate capability by reducing the needed time to collect this charge. To keep the RPC efficiency high, a sensitive, low-noise and high time resolution front-end electronics is needed to cope with the lower charge signal of the new RPC. An ASIC called PETIROC that has all these characteristics has been selected to read out the strips of new chambers. Thin (0.6 mm) printed circuit board, 160 cm long, equipped with pickup strips of 0.75 cm average pitch, will be inserted between the two new RPC's gaps. The strips will be read out from both ends, and the arrival time difference of the two ends will be used to determine the hit position along the strip. Results from the improved RPC equipped with the new readout system and exposed to cosmic muons in the high irradiation environment at CERN GIF++ facility are presented in this work.
Abstract
The expected radiation background in the CMS RPC system has been studied using the MC prediction with the CMS FLUKA simulation of the detector and the cavern. The MC geometry used in the ...analysis describes very accurately the present RPC system but still does not include the complete description of the RPC upgrade region with pseudorapidity 1.9 < |η| < 2.4. Present results will be updated with the final geometry description, once it is available. The radiation background has been studied in terms of expected particle rates, absorbed dose and fluence. Two High Luminosity LHC (HL-LHC) scenarios have been investigated — after collecting 3000 and 4000 fb
-1
. Estimations with safety factor of 3 have been considered, as well.
Abstract
During the upcoming High Luminosity phase of the Large Hadron Collider (HL-LHC), the integrated luminosity of the accelerator will increase to 3000 fb
−1
. The expected experimental ...conditions in that period in terms of background rates, event pileup, and the probable aging of the current detectors present a challenge for all the existing experiments at the LHC, including the Compact Muon Solenoid (CMS) experiment. To ensure a highly performing muon system for this period, several upgrades of the Resistive Plate Chamber (RPC) system of the CMS are currently being implemented. These include the replacement of the readout system for the present system, and the installation of two new RPC stations with improved chamber and front-end electronics designs. The current overall status of this CMS RPC upgrade project is presented.
In the High Luminosity Large Hadron Collider (HL-LHC) program, during the next years, the instantaneous luminosity will increase up to 5×1034 cm−2 s−1 which means a factor five higher than the ...nominal LHC luminosity. In that period, the present CMS Resistive Plate Chambers (RPC) system will be subjected to background rates higher than those for which the detectors have been designed, which could affect the detector properties and induce aging effects. To study whether the present RPC system can sustain the hard background conditions during the HL-LHC running period, a dedicated longevity test is ongoing at the CERN Gamma Irradiation Facility, where a few spare RPCs are exposed to high gamma radiation for a long term period to mimic the HL-LHC operational conditions. During the longevity test, the main detector parameters are continuously monitored as a function of the integrated charge. Preliminary results of the study, after having collected a sufficient amount of the expected integrated charge at HL-LHC, will be presented.
The CMS experiment has 1054 RPCs in its muon system. Monitoring their currents is the first essential step towards maintaining the stability of the CMS RPC detector performance. The current depends ...on several parameters such as applied voltage, luminosity, environmental conditions, etc. Knowing the influence of these parameters on the RPC current is essential for the correct interpretation of its instabilities as they can be caused either by changes in external conditions or by malfunctioning of the detector in the ideal case. We propose a Machine Learning(ML) based approach to be used for monitoring the CMS RPC currents. The approach is crucial for the development of an automated monitoring system capable of warning for possible hardware problems at a very early stage, which will contribute further to the stable operation of the CMS RPC detector.
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