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71.
Fresh fruits and vegetables are increasingly being recognized as vectors for foodborne illness. In 1998, an on-farm food safety program was developed for the Ontario Greenhouse Vegetable Growers (OGVG) in Ontario, Canada. This hazard analysis critical control point-based system was designed to reduce the potential of microbial contamination along the entire production and distribution process. A previous report (D. A. Powell, M. Bobadilla-Ruiz, A. Whitfield, M. W. Griffiths, and A. Luedtke, J. Food Prot. 65:918-923) outlined the first 2 years of the program; the present report documents the third year of the program's implementation. Through individual on-site grower visits and the microbiological testing of produce and water, the program's OGVG member requirements were determined, and the program's success was assessed. Growers' knowledge, understanding, and awareness of microbial risks associated with fresh produce have increased, and improvements in practices used in greenhouses and packing sheds were noted. 相似文献
72.
James S. Swensen Evgueni Polikarpov Amber Von Ruden Liang Wang Linda S. Sapochak Asanga B. Padmaperuma 《Advanced functional materials》2011,21(17):3250-3258
Data from a series of phosphorescent blue organic light‐emitting devices with emissive layers consisting of either 4,4′‐bis(N‐carbazolyl)‐2,2′‐biphenyl (CBP):6% bis[(4,6‐difluorophenyl)pyridinato‐N,C2](picolinato)iridium(III) (FIrpic) or bis(9‐carbazolyl)benzene (mCP):6% FIrpic show that the triplet energy of the hole and electron transport layers can have a larger influence on the external quantum efficiency of an operating device than the triplet energy of the host material. A maximum external quantum efficiency of 14% was obtained for CBP:6% FIrpic devices which is nearly double all other published CBP:6% FIrpic results. A new host material, 4‐(diphenylphosphoryl)‐N,N‐di‐p‐tolylaniline (DHM‐A2), which has a triplet energy lower than that of FIrpic is also reported. Devices fabricated using DHM‐A2 show improved performance (lower drive voltage and higher external quantum efficiency) over devices using 4‐(diphenylphosphoryl)‐N,N‐diphenylaniline (HM‐A1), a high performance ambipolar DHM‐A2 analogue with a triplet energy greater than FIrpic. Nearly 18% external quantum efficiency was obtained for the DHM‐A2:5% FIrpic devices. The results suggest modified design rules for the development of high performance host materials: more focus can be placed on molecular structures that provide good charge transport (ambipolarity for charge balance) and good molecular stability (for long lifetimes) rather than first focusing on the triplet energy of the host material. 相似文献
73.
Role of intestinal microbiota in the generation of polyphenol‐derived phenolic acid mediated attenuation of Alzheimer's disease β‐amyloid oligomerization 下载免费PDF全文
74.
The demand for bottled water has grown tremendously in recent years, together with concern about its environmental impacts. The authors surveyed individuals in Phoenix, Arizona about their water consumption behaviour, socio-demographic characteristics, perception of water quality and trust in the government's willingness to respond to water quality issues. Using a logit model, the authors then tested the relationship between the respondents' characteristics and bottled water consumption for cooking and drinking in the home. Our results indicate that bottled water consumption reflects lifestyle choice not environmental concerns. 相似文献
75.
Joseph A. Frankl Yu An Amber Sherwood Guiyang Hao Feng-Yun Huang Pawan Thapa Deborah J. Clegg Xiankai Sun Philipp E. Scherer Orhan K.
z 《International journal of molecular sciences》2022,23(9)
Obesity is a leading cause of preventable death and morbidity. To elucidate the mechanisms connecting metabolically active brown adipose tissue (BAT) and metabolic health may provide insights into methods of treatment for obesity-related conditions. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18FDG-PET/CT) is traditionally used to image human BAT activity. However, the primary energy source of BAT is derived from intracellular fatty acids and not glucose. Beta-methyl-p-iodophenylpentadecanoic acid (BMIPP) is a fatty acid analogue amenable to in vivo imaging by single photon emission computed tomography/CT (SPECT/CT) when radiolabeled with iodine isotopes. In this study, we compare the use of 18FDG-PET/CT and 125I-BMIPP-SPECT/CT for fat imaging to ascertain whether BMIPP is a more robust candidate for the non-invasive evaluation of metabolically active adipose depots. Interscapular BAT, inguinal white adipose tissue (iWAT), and gonadal white adipose tissue (gWAT) uptake of 18FDG and 125I-BMIPP was quantified in mice following treatment with the BAT-stimulating drug CL-316,243 or saline vehicle control. After CL-316,243 treatment, uptake of both radiotracers increased in BAT and iWAT. The standard uptake value (SUVmean) for 18FDG and 125I-BMIPP significantly correlated in these depots, although uptake of 125I-BMIPP in BAT and iWAT more closely mimicked the fold-change in metabolic rate as measured by an extracellular flux analyzer. Herein, we find that imaging BAT with the radioiodinated fatty acid analogue BMIPP yields more physiologically relevant data than 18FDG-PET/CT, and its conventional use may be a pivotal tool for evaluating BAT in both mice and humans. 相似文献
76.
The purpose of this research was to incorporate 0% to 30% chia seed flour into rice flour gluten-free layer cake and evaluate its effect on nutritional qualities and physicochemical properties. The supplement of chia seed flour resulted in higher batter viscosity, hardness of gluten free layer cake, crude protein, fat, ash, α-linolenic acid (increase up to 10.2% of total fatty acid), total phenolics content, and reducing power but the lower crust, crumb white index, cohesiveness, and resilience of gluten-free layer cake was found. Substitution of rice flour with 10% prehydrated chia seed flour can achieve a higher center height and volume index of gluten-free layer cakes. Higher carosine and angiotension I-converting enzyme (ACE) inhibitory activity was observed in the supplement of 10% chia seed flour when compared to a rice flour layer cake. Gluten-free layer cake with 10% prehydrated chia seeds flour had similar overall acceptability, texture, flavor, and odor scores except for lower appearance score to those of gluten-free layer cake made with 100% rice flour and layer cake made with 100% wheat flour. Incorporation of 10% prehydrated chia seed flour results in more desirable volume index of gluten-free layer cake and it is feasible for gluten-free layer cake application. Gluten-free layer cakes with improved quality characteristics and high nutritional value can be manufactured by the incorporation of chia seed flour. 相似文献
77.
78.
Steinmetz NF Ablack AL Hickey JL Ablack J Manocha B Mymryk JS Luyt LG Lewis JD 《Small (Weinheim an der Bergstrasse, Germany)》2011,7(12):1664-1672
Multivalent nanoparticles have several key advantages in terms of solubility, binding avidity, and uptake, making them particularly well suited to molecular imaging applications. Herein is reported the stepwise synthesis and characterization of NIR viral nanoparticles targeted to gastrin-releasing peptide receptors that are over-expressed in human prostate cancers. The pan-bombesin analogue, [β-Ala11, Phe13, Nle14]bombesin-(7-14), is conjugated to cowpea mosaic virus particles functionalized with an NIR dye (Alexa Fluor 647) and polyethylene glycol (PEG) using the copper(I)-catalyzed azide-alkyne cycloaddition reaction. Targeting and uptake in human PC-3 prostate cells is demonstrated in vitro. Tumor homing is observed using human prostate tumor xenografts on the chicken chorioallantoic membrane model using intravital imaging. Further development of this viral nanoparticle platform may open the door to potential clinical noninvasive molecular imaging strategies. 相似文献
79.
Acyl-CoA:lysophosphatidylcholine acyltransferase (LPCAT; EC 2.3.1.23) catalyzes the acyl-CoA-dependent acylation of lysophosphatidylcholine
(LPC) to produce PC and CoA. LPCAT activity may affect the incorporation of fatty acyl moieties at the sn-2 position of PC where PUFA are formed and may indirectly influence seed TAG composition. LPCAT activity in microsomes prepared
from microspore-derived cell suspension cultures of oilseed rape (Brassica napus L. cv Jet Neuf) was assayed using [1-14C]acyl-CoA as the fatty acyl donor. LPCAT activity was optimal at neutral pH and 35°C, and was inhibited by 50% at a BSA concentration
of 3 mg mL−1. At acyl-CoA concentrations above 20 μM, LPCAT activity was more specific for oleoyl (18∶1)-CoA than stearoyl (18∶0)- and
palmitoyl (16∶0)-CoA. Lauroyl (12∶0)-CoA, however, was not an effective acyl donor. LPC species containing 12∶0, 16∶0, 18∶0,
or 18∶1 as the fatty acyl moiety all served as effective acyl acceptors for LPCAT, although 12∶0-LPC was somewhat less effective
as a substrate at lower concentrations. The failure of LPCAT to catalyze the incorporation of a 12∶0 moiety from acyl-CoA
into PC is consistent with the tendency of acyltransferases to discriminate against incorporation of this fatty acyl moiety
at the sn-2 position of TAG from the seed oil of transgenic B. napus expressing a medium-chain thioesterase. 相似文献
80.