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1.
Catherine O'Leary Yvonne de Kluizenaar Piet Jacobs Wouter Borsboom Ian Hall Benjamin Jones 《Indoor air》2019,29(3):423-438
There is growing awareness that indoor exposure to particulate matter with diameter ≤ 2.5 μm (PM2.5) is associated with an increased risk of adverse health effects. Cooking is a key indoor source of PM2.5 and an activity conducted daily in most homes. Population scale models can predict occupant exposures to PM2.5, but these predictions are sensitive to the emission rates used. Reported emission rates are highly variable and are typically for the cooking of single ingredients and not full meals. Accordingly, there is a need to assess PM2.5 emissions from the cooking of complete meals. Mean PM2.5 emission rates and source strengths were measured for four complete meals. Temporal PM2.5 concentrations and particle size distributions were recorded using an optical particle counter (OPC), and gravimetric sampling was used to determine calibration factors. Mean emission rates and source strengths varied between 0.54—3.7 mg/min and 15—68 mg, respectively, with 95% confidence. Using a cooker hood (apparent capture efficiency > 90%) and frying in non‐stick pans were found to significantly reduce emissions. OPC calibration factors varied between 1.5 and 5.0 showing that a single value cannot be used for all meals and that gravimetric sampling is necessary when measuring PM2.5 concentrations in kitchens. 相似文献
2.
Paul W. Francisco Stacy Gloss Jonathan Wilson William Rose Yigang Sun Sherry L. Dixon Jill Breysse Ellen Tohn David E. Jacobs 《Indoor air》2020,30(1):147-155
Energy retrofits can reduce air exchange, raising the concern of whether indoor radon and moisture levels could increase. This pre/post-intervention study explored whether simple radon interventions implemented in conjunction with energy retrofits can prevent increases in radon and moisture levels. Treatment homes (n = 98) were matched with control (no energy retrofits or radon intervention) homes (n = 12). Control homes were matched by geographic location and foundation type. t-tests were used to determine whether post-energy retrofit radon and moisture level changes in treatment homes significantly differed from those in control homes. The radon interventions succeeded in preventing statistically significant increases in first floor radon using arithmetic (p = 0.749) and geometric means (p = 0.120). In basements, arithmetic (p = 0.060) and geometric (p = 0.092) mean radon levels statistically significantly increased, consistent with previous studies which found that basement radon levels may increase even if first floor levels remain unchanged. Changes in infiltration were related to changes in radon (p = 0.057 in basements; p = 0.066 on first floors). Only 58% of the change in infiltration was due to air sealing, with the rest due to weather changes. There was no statistically significant association between air sealing itself and radon levels on the first floor (p = 0.664). Moisture levels also did not significantly increase. 相似文献
3.
Russell C. Rockne Andrew D. Trister Joshua Jacobs Andrea J. Hawkins-Daarud Maxwell L. Neal Kristi Hendrickson Maciej M. Mrugala Jason K. Rockhill Paul Kinahan Kenneth A. Krohn Kristin R. Swanson 《Journal of the Royal Society Interface》2015,12(103)
Glioblastoma multiforme (GBM) is a highly invasive primary brain tumour that has poor prognosis despite aggressive treatment. A hallmark of these tumours is diffuse invasion into the surrounding brain, necessitating a multi-modal treatment approach, including surgery, radiation and chemotherapy. We have previously demonstrated the ability of our model to predict radiographic response immediately following radiation therapy in individual GBM patients using a simplified geometry of the brain and theoretical radiation dose. Using only two pre-treatment magnetic resonance imaging scans, we calculate net rates of proliferation and invasion as well as radiation sensitivity for a patient''s disease. Here, we present the application of our clinically targeted modelling approach to a single glioblastoma patient as a demonstration of our method. We apply our model in the full three-dimensional architecture of the brain to quantify the effects of regional resistance to radiation owing to hypoxia in vivo determined by [18F]-fluoromisonidazole positron emission tomography (FMISO-PET) and the patient-specific three-dimensional radiation treatment plan. Incorporation of hypoxia into our model with FMISO-PET increases the model–data agreement by an order of magnitude. This improvement was robust to our definition of hypoxia or the degree of radiation resistance quantified with the FMISO-PET image and our computational model, respectively. This work demonstrates a useful application of patient-specific modelling in personalized medicine and how mathematical modelling has the potential to unify multi-modality imaging and radiation treatment planning. 相似文献
4.
Graf Urs U. Honingh Cornelia E. Jacobs Karl Stutzki Jürgen 《Journal of Infrared, Millimeter and Terahertz Waves》2015,36(10):896-921
Journal of Infrared, Millimeter, and Terahertz Waves - We review the development of multi-pixel heterodyne receivers for astronomical research in the submillimeter and terahertz spectral domains.... 相似文献
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Dr. Eric M. Lewandowski Dr. Łukasz Szczupak Dr. Aleksandra Kowalczyk Dr. Gracia Mendoza Prof. Manuel Arruebo Lian M. C. Jacobs Prof. Paweł Stączek Prof. Yu Chen Prof. Konrad Kowalski 《Chembiochem : a European journal of chemical biology》2020,21(15):2187-2195
The conjugation of organometallic groups to current β-lactam antibiotics is a field of increasing study due to the ability of certain organometallic groups to enhance the antibiotic potency of these drugs. Herein, we report the antibacterial properties of two metallocenyl (ferrocenyl and ruthenocenyl) 7-aminocephalosporanic acid (7-ACA) antibiotic conjugates. Continuing a trend we found in our previous studies, the ruthenocenyl conjugate showed greater antibacterial activity than its ferrocenyl counterpart. Compared with the previously published 7-aminodesacetoxycephalosporanic acid (7-ADCA) conjugates, the 3-acetyloxymethyl group significantly improved the compounds’ activity. Furthermore, the Rc-7-ACA compound was more active against clinical Staphylococcus aureus isolates than the ampicillin reference. Noticeably, neither of the two new compounds showed an undesirable toxic effect in HeLa and L929 cells at the concentrations at which they displayed strong antibacterial effects. The antibacterial activity of the two metallocenyl 7-ACA derivatives was further confirmed by scanning electron microscopy (SEM). SEM micrographs showed that bacteria treated with metallocenyl 7-ACA derivatives feature cell wall damage and morphology changes. Using a CTX-M-14 β-lactamase competition assay based on nitrocefin hydrolysis, we showed that the Rc-7-ACA bound more favorably to CTX-M-14 than its ferrocenyl counterpart, again confirming the superiority of the ruthenocenyl moiety over the ferrocenyl one in interacting with proteins. We also report a 1.47 Å resolution crystal structure of Rc-7-ACA in complex with the CTX-M-14 E166A mutant, an enzyme sharing a similar active site configuration with penicillin-binding proteins, the molecular target of β-lactam antibiotics. These results strengthen the case for the antibacterial utility of the Rc and Fc groups. 相似文献
7.
Paul W. Johns Ananya Das Esther M. Kuil Wesley A. Jacobs Karen J. Schimpf Daniel J. Schmitz 《International Journal of Food Science & Technology》2015,50(2):421-430
The rate of vitamin B12 loss was 3X greater in heated, chocolate‐flavoured milk than in unflavoured milk. Studies of B12 stability in the presence of cocoa powder components were performed to identify the reactive agents. Cocoa polyphenols with a strong capacity both for reduction and for peroxide generation accelerated B12 destruction as much as 20‐fold vs. polyphenols without both capacities. Polyphenols with both capacities include the cocoa polyphenol (+)‐catechin and oligomers thereof, but also the structurally related polyphenols gallic acid, caffeic acid and (?)‐epigallocatechin gallate. The demonstrated physical affinity of cocoa powder for B12 was a significant factor in the destructive process. B12 may exhibit decreased stability in heated, neutral pH, polyphenol‐fortified foods. 相似文献
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J. D. Benson L. O. Bubulac A. Wang R. N. Jacobs J. M. Arias M. Jaime-Vasquez P. J. Smith L. A. Almeida A. Stoltz P. S. Wijewarnasuriya A. Yulius M. Carmody M. Reddy J. Peterson S. M. Johnson J. Bangs D. D. Lofgreen 《Journal of Electronic Materials》2018,47(10):5671-5679
In this work, impurity ‘hot spot’ macro-defects—high impurity level macro-defect contaminates were examined. ‘Hot spots’ have very high localized concentrations of: K, Mg, Ni, Cr, Mn, Ca, Al, Na, Fe, and Cu. For example, these ‘hot spot’ macro-defects can have Cu concentrations >?1?×?1018 cm?3. Focused ion beam scanning transmission electron microscopy analysis of four ‘hot spots’ was performed. The origin of ‘hot spot’ defects is unresolved—however, our analysis has shown ‘hot spots’ can arise due to molecular beam epitaxy spit defects and CdZnTe substrate defects. The estimated ‘hot spot’ density is ~?30 cm?2. The presence of impurity ‘hot spot’ macro-defects in HgCdTe/CdZnTe is confirming evidence for the occurrence of L. Bubulac’s impurity ‘pipe’ mechanism. 相似文献