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1.
Toshiaki Nishihata Mayumi Ishizaka Sigeharu Yokohama Alice C. Martino Roger E. Gordon 《Drug development and industrial pharmacy》1993,19(20):2679-2698
The effects of particle size and food on the absolute bioavailability of U-78875 in dogs after oral administration of either a suspension or tablet dosage form were investigated. A reduction of particle size caused a significant increase in bioavailability along with an increase in dissolution rate. Additionally, both suspension and tablet dosage forms administered after food caused an increase in bioavailability. Thus, to accelerate drug dissolution, a reduction of U-78875 particle size from the unmilled state is important for the optimization of formulation compositions. To increase the bioavailability of U-78875, postprandial dosing should be considered. 相似文献
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3.
Emily Jackson Levitt David L. Pelletier Charlotte Dufour Alice N. Pell 《Food Security》2011,3(3):363-381
Coordination across sectors to address undernutrition with its varied underlying causes remains a challenge in developing countries. In Afghanistan, harmonization of health and agriculture policies and actions to reduce endemic undernutrition occurred during 2002-2007. This qualitative case study explores the forms of harmonization, enabling features and constraints in the policy process. We interviewed 57 stakeholders (39 central level, 18 provincial) involved in public nutrition or food security issues. Forms of harmonization included written policies, reseach, training and advocacy. Important features of the policy process included: policy entrepreneurs with operational and strategic capacity, consensus-building using a shared causal framework, working groups and strategic alliances. This case presents an interesting alternative to a national nutrition coordinating body, an approach that has met with mixed results, often due to the lack of authority, budget, and operational capacity of such a body to oversee ministries and enforce national nutrition objectives. Mid-level professionals mobilized into task forces achieved much with the support of national and international partners. This study highlights the importance of building capacity for sustaining change through local institutions. 相似文献
4.
Paul T. Vianco Jerome A. Rejent Alice C. Kilgo 《Journal of Electronic Materials》2004,33(11):1389-1400
The compression creep behavior was studied for the ternary solder alloy 95.5Sn-3.9Ag-0.6Cu in the as-cast condition. Samples
were tested under stresses of 2–45 MPa and temperatures of −25–160°C. There was a significant variability in the creep curve
shape, strain magnitude, and steady-state strain-rate properties. A multivariable linear-regression analysis of the steady-state
strain-rate data, using the sinh-law stress representation, indicated two mechanisms distinguished by low- and high-temperature
regimes of −25–75°C and 75–160°C, respectively. The sinh-law stress exponent (n) and apparent-activation energy (ΔH) in the
−25–75°C regime were 4.4 ± 0.7 kJ/mol and 25 ± 7 kJ/mol (63% confidence intervals), respectively. Those same parameters in
the 75–160°C regime were 5.2±0.8 kJ/mol and 95±14 kJ/mol, respectively, for the high-temperature regime. The values of ΔH
suggested a short-circuit diffusion mechanism at low temperatures and a lattice or bulk-diffusion mechanism at high temperatures.
The stress dependency of the steady-state strain rate did not indicate a strong power-law breakdown behavior or a threshold
stress phenomenon. Cracks and grain-boundary sliding were not observed in any of the samples. As the creep temperature increased,
a coarsened particle boundary and particle depletion zone formed in the region of fine Ag3Sn particles that existed between the Sn-rich phase areas. The coarsened particle boundary, as well as accelerated coarsening
of Ag3Sn particles, were direct consequences of the creep deformation process. 相似文献
5.
Protected Working Capacity Envelope (PWCE) has been proposed to simplify resource management and traffic control for survivable
WDM networks. In a PWCE-based network, part of the link capacity is reserved for accommodating working routes, and the remaining
capacity is reserved for backup routes. The shortest path routing is applied in PWCE-based networks. An arrival call is accepted
only when each link along the shortest path has a free working channel. Such a working path routing scheme greatly simplifies
the call admission control process for dynamic traffic, and it is especially suitable for implementation in a distributed
manner among network nodes. In this article, we investigate two protection strategies: Bundle Protection (BP) and Individual
Protection (IDP). In BP, only one backup path can be used to protect a failure component, whereas multiple backup paths can
be used in IDP. We formulate four mixed integer non-linear programming (MINLP) problems using BP and IDP strategies for single
link and single node failure protection. Each model is designed to determine link metrics for shortest working path routing,
working and backup channel assignments, and backup path planning. Our objective is to minimize call-blocking probability on
the bottleneck link. Since these models are highly non-linear and non-convex, it is difficult to obtain exact global optimal
solutions. We propose a Simulated Annealing-based Heuristic (SAH) algorithm to obtain near optimal solutions. This SAH adopts
the concepts of simulated annealing as well as the bi-section technique to minimize call-blocking probabilities. To evaluate
the performance, we made simulation comparisons between SAH and the unity link weight assignment scheme. The results indicate
that SAH can greatly reduce call-blocking probabilities on benchmark and the randomly generated networks. 相似文献
6.
Alice E. Snape Jody L. Turner Hassan M. El-Dessouky Mohamed N. Saleh Hannah Tew Richard J. Scaife 《Applied Composite Materials》2018,25(4):735-746
The work presented here focusses on the developments in the stabilising and trimming of 3D woven preforms. Dry fibre preforms are notoriously difficult to trim; once a fabric is cut, it loses its edge stability and consequently the fabric frays. The result is an unstable fabric which can easily be displaced/ distorted prior to composite manufacturing. In this work, three stabilisation and three trimming techniques were investigated. Of the stabilisation techniques these included powder binder, thermoplastic binder yarn (activated to give fabric stabilization); and polyester stitching. The stabilised fabrics were trimmed to near-net-shape using different trimming techniques. The trimming techniques investigated were laser, clicker press and ultrasonic knife. Each stabilisation method was trialled with each trimming method to assess the most suitable combination. The assessment of quality and suitability was made by observing the level of stabilisation, amount of fraying fibres, quality of the cut, ease of application and repeatability of the process. This paper details the assessments made for each combination alongside practical application conclusions. The key findings were; cutting by means of a laser is capable of sealing the fabric edges, producing high edge quality. Stitching as a method of stabilising is not sufficient in preventing fibres from moving during the cutting process, hence producing an unclean cut. 相似文献
7.
Schecter A Harris TR Shah N Musumba A Päpke O 《Molecular nutrition & food research》2008,52(2):266-272
We and others recently began studying brominated flame retardant levels in various matrices in the US including human milk and other food. This paper reviews the food studies. In our studies, ten to thirteen polybrominated diphenyl ether (PBDE) congeners were measured, usually including BDE 209. All US women's milk samples were contaminated with PBDEs from 6 to 419 ng/g, lipid, orders of magnitude higher than levels reported in European studies, and are the highest reported worldwide. We compared our market basket studies of meat, fish and dairy products with other US food studies of meat and fish. US studies showed somewhat higher levels of PBDEs than reported elsewhere. Fish were most highly contaminated (median 616 pg/g), then meat (median190 pg/g) and dairy products (median 32.2 pg/g). However, unlike some European countries where fish predominates, dietary intake of PBDEs in the US is mostly from meat, then fish and then dairy products. Broiling can decrease the amount of PBDEs per serving. We also measured levels of hexabromocyclododecane (HBCD), another brominated flame retardant, in human milk. The levels are lower than PBDEs, 0.16-1.2 ng/g, similar to European levels, unlike PBDEs where US levels are much higher than European levels. 相似文献
8.
Juliana Milheiro Luís Filipe-Ribeiro Alice Vilela Fernanda Cosme 《Critical reviews in food science and nutrition》2019,59(9):1367-1391
The presence of 4-ethylphenol, 4-ethylguaiacol and 4-ethylcatechol in red wines affect negatively their aroma conferring horsy, barnyard, smoky and medicinal aromatic notes. These volatile phenols formed from free hydroxycinnamic acids and their ethyl esters by Dekkera/Brettanomyces yeasts, can contaminate wines. Their formation can cause serious negative economic impact to the wine industry worldwide as consumers tend to reject these wines. For these reasons various preventive and remedial treatments have been studied. This review summarises the wine microbial volatile phenols formation, preventive measures during winemaking and remedial treatments in finished wines along with their advantages and limitations for dealing with this sensory defect and impact on wine quality. Also it is important to control the levels of volatile phenols in wines using fast and convenient analytical methods namely with a detection limit below their olfactory perception threshold. The analytical methods available for quality control and performance characteristics as well their advantages and disadvantages when dealing with a complex matrix like wine are discussed in detail. 相似文献
9.
Impact of enzyme inactivation conditions during the generation of whey protein hydrolysates on their physicochemical and bioactive properties
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Solène Le Maux Alice B. Nongonierma Claire Lardeux Richard J. FitzGerald 《International Journal of Food Science & Technology》2018,53(1):219-227
The thermal inactivation conditions (75 °C × 35 min, 80 °C × 10 min, 85 °C × 5 min and 90 °C × 5 min) for Protamex? following bovine whey protein concentrate (WPC) hydrolysis was studied with the view to limiting WPC hydrolysate (WPH) aggregation while maintaining bioactivity. A decrease in the amount of large WPH aggregates formed was observed at inactivation temperatures ≤85 °C. However, the WPC appeared to be more hydrolysed on heating at 75 °C × 35 min, as Protamex? was active for longer under these heating conditions. Significantly (P < 0.05), higher WPH antioxidant (oxygen radical absorbance capacity – ORAC) activity was obtained on inactivation at temperatures ≤80 °C. In contrast, the dipeptidyl peptidase IV (DPP‐IV) inhibitory properties of all WPH samples were similar (P > 0.05). A reduction in thermal treatment from 90 °C × 5 min to 85 °C × 5 min was sufficient to decrease the amount of large aggregates formed in the hydrolysate without altering its bioactive properties. 相似文献
10.
Estrogen content of dairy and swine wastes 总被引:3,自引:0,他引:3
Raman DR Williams EL Layton AC Burns RT Easter JP Daugherty AS Mullen MD Sayler GS 《Environmental science & technology》2004,38(13):3567-3573
Naturally occurring estrogens in animal wastes may cause negative environmental impacts, yet their abundance in animal waste treatment and storage structures is poorly documented. To better quantify estrogen concentrations in animal wastes, multiple waste samples were collected from treatment and storage structures at dairy and swine facilities and analyzed for concentrations of 17beta-estradiol (E2), estrone (E1), and 17alpha-estradiol by gas chromatography-mass spectroscopy and by enzyme linked immunosorbent assay (E2 only). Mass ratios of each estrogen to the macronutrients nitrogen, phosphorus, and potassium were also determined. Because manure application rates are typically macronutrient-based, estrogen to macronutrient ratios are proportional to areal mass application rates of estrogen to fields. Swine farrowing waste (from farrowing sows and piglets) had the highest ratios of E2 to macronutrients. Mean ratios in swine farrowing waste were roughly twice those in swine finishing waste (from growing male and nonpregnant female animals) and more than four times higher than those in dairy waste (from lactating cows in various stages of their reproductive cycles); these differences were statistically significant (alpha = 0.05). Estrone followed a similar trend. In contrast, ratios of 17alpha-estradiol to macronutrients were highest in dairy operations. These results can be used to better predict estrogen loading rates on fields receiving swine and dairy wastes. 相似文献