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41.
State Space Search with Prioritised Soft Constraints 总被引:2,自引:0,他引:2
This paper addresses two issues: how to choose between solutions for a problem specified by multiple criteria, and how to search for solutions in such situations. We argue against an approach common in decision theory, reducing several criteria to a single cost (e.g., using a weighted sum cost function) and instead propose a way of partially ordering solutions satisfying a set of prioritised soft constraints. We describe a generalisation of the A* search algorithm which uses this ordering and prove that under certain reasonable assumptions the algorithm is complete and optimal. 相似文献
42.
Corn zein and wheat gliadin protein are compounded into synthetic cis-1,4-polyisoprene rubber (IR) and sulfur-cured in a zinc oxide (ZnO)-free system. The curing kinetics and mechanical and morphological properties are compared to a ZnO-activated or carbon black (CB)-reinforced cure system. The proteins provide reversion resistance and reinforcement to IR at filler loadings as low as 1 part per hundred rubber (phr). The zein-IR composites exhibit higher moduli, better filler–matrix adhesion, and less filler agglomeration/migration than gliadin-IR because zein is more chemically compatible with IR. The gliadin-IR composites have a lower percent set and hysteresis, indicating the formation of an elastic restoring gliadin network. Optimal properties are achieved at 2-phr gliadin and 4-phr zein. At gliadin loading >2 phr and zein loading >4 phr, the protein domain size increases and mechanical properties deteriorate. At equal filler loading, property improvements over CB-IR are observed for one or both proteins. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48141. 相似文献
43.
Bacterial Ecology of Fermented Cucumber Rising pH Spoilage as Determined by Nonculture‐Based Methods 下载免费PDF全文
Eduardo Medina Ilenys M. Pérez‐Díaz Fred Breidt Janet Hayes Wendy Franco Natasha Butz María Andrea Azcarate‐Peril 《Journal of food science》2016,81(1):M121-M129
Fermented cucumber spoilage (FCS) characterized by rising pH and the appearance of manure‐ and cheese‐like aromas is a challenge of significant economical impact for the pickling industry. Previous culture‐based studies identified the yeasts Pichia manshurica and Issatchenkia occidentalis, 4 Gram‐positive bacteria, Lactobacillus buchneri, Lactobacillus parrafaraginis, Clostridium sp., and Propionibacterium and 1 Gram‐negative genus, Pectinatus, as relevant in various stages of FCS given their ability to metabolize lactic acid. It was the objective of this study to augment the current knowledge of FCS using culture‐independent methods to microbiologically characterize commercial spoilage samples. Ion Torrent data and 16S rRNA cloning library analyses of samples collected from commercial fermentation tanks confirmed the presence of L. rapi and L. buchneri and revealed the presence of additional species involved in the development of FCS such as Lactobacillus namurensis, Lactobacillus acetotolerans, Lactobacillus panis, Acetobacter peroxydans, Acetobacter aceti, and Acetobacter pasteurianus at pH below 3.4. The culture‐independent analyses also revealed the presence of species of Veillonella and Dialister in spoilage samples with pH above 4.0 and confirmed the presence of Pectinatus spp. during lactic acid degradation at the higher pH. Acetobacter spp. were successfully isolated from commercial samples collected from tanks subjected to air purging by plating on Mannitol Yeast Peptone agar. In contrast, Lactobacillus spp. were primarily identified in samples of FCS collected from tanks not subjected to air purging for more than 4 mo. Thus, it is speculated that oxygen availability may be a determining factor in the initiation of spoilage and the leading microbiota. 相似文献
44.
Ciara N. Murphy Susan P. Walker Teresa M. MacDonald Emerson Keenan Natalie J. Hannan Mary E. Wlodek Jenny Myers Jessica F. Briffa Tania Romano Alexandra Roddy Mitchell Carole-Anne Whigham Ping Cannon Tuong-Vi Nguyen Manju Kandel Natasha Pritchard Stephen Tong Tuuhevaha J. Kaituu-Lino 《International journal of molecular sciences》2021,22(14)
Biomarkers for placental dysfunction are currently lacking. We recently identified SPINT1 as a novel biomarker; SPINT2 is a functionally related placental protease inhibitor. This study aimed to characterise SPINT2 expression in placental insufficiency. Circulating SPINT2 was assessed in three prospective cohorts, collected at the following: (1) term delivery (n = 227), (2) 36 weeks (n = 364), and (3) 24–34 weeks’ (n = 294) gestation. SPINT2 was also measured in the plasma and placentas of women with established placental disease at preterm (<34 weeks) delivery. Using first-trimester human trophoblast stem cells, SPINT2 expression was assessed in hypoxia/normoxia (1% vs. 8% O2), and following inflammatory cytokine treatment (TNFα, IL-6). Placental SPINT2 mRNA was measured in a rat model of late-gestational foetal growth restriction. At 36 weeks, circulating SPINT2 was elevated in patients who later developed preeclampsia (p = 0.028; median = 2233 pg/mL vs. controls, median = 1644 pg/mL), or delivered a small-for-gestational-age infant (p = 0.002; median = 2109 pg/mL vs. controls, median = 1614 pg/mL). SPINT2 was elevated in the placentas of patients who required delivery for preterm preeclampsia (p = 0.025). Though inflammatory cytokines had no effect, hypoxia increased SPINT2 in cytotrophoblast stem cells, and its expression was elevated in the placental labyrinth of growth-restricted rats. These findings suggest elevated SPINT2 is associated with placental insufficiency. 相似文献
45.
Whipple Natasha; Bernier Annie; Mageau Geneviève A. 《Canadian Metallurgical Quarterly》2009,50(4):219
Understanding the intergenerational transmission of attachment patterns has been a main focus of attachment research for many years. Most of the empirical work conducted on this question has addressed maternal sensitivity to infants’ attachment needs. Given that security of attachment is defined as an attachment/exploration balance, some researchers have stressed the need to explore maternal behaviours in the context of infant exploration. The authors propose that self-determination theory (SDT) could contribute to attachment work in this respect given that it has clearly operationalized parental exploration-related behaviours and has related them to numerous child outcomes. This article highlights conceptual, empirical, and methodological parallels that can be drawn between SDT and attachment theory, thus suggesting that they could be complementary on many levels. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
Osberg Timothy M.; Atkins Lindsay; Buchholz Laura; Shirshova Victoria; Swiantek Andrew; Whitley Jessica; Hartman Sabrina; Oquendo Natasha 《Canadian Metallurgical Quarterly》2010,24(1):1
This article reports the development and validation of the College Life Alcohol Salience Scale (CLASS), which assesses college students’ beliefs about the centrality of alcohol to the college experience. Developed using procedures designed to increase its ecological validity, the CLASS was administered to three samples of college students (total N = 571). Its unidimensional factor structure was first established via exploratory factor analysis and parallel analysis on one sample and then verified via confirmatory factor analysis on a separate sample. Scores on the CLASS were predictably related to a nomological network of drinking and personality variables and it provided incremental validity in accounting for drinking frequency and amount, when added to drinking motive scores. The importance of assessing and developing interventions to target the types of beliefs measured by the CLASS is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
47.
Natasha E. Hatton Dr. Christoph G. Baumann Dr. Martin A. Fascione 《Chembiochem : a European journal of chemical biology》2021,22(4):613-629
During their lifetime almost half of women will experience a symptomatic urinary tract infection (UTI) with a further half experiencing a relapse within six months. Currently UTIs are treated with antibiotics, but increasing antibiotic resistance rates highlight the need for new treatments. Uropathogenic Escherichia coli (UPEC) is responsible for the majority of symptomatic UTI cases and thus has become a key pathological target. Adhesion of type one pilus subunit FimH at the surface of UPEC strains to mannose-saturated oligosaccharides located on the urothelium is critical to pathogenesis. Since the identification of FimH as a therapeutic target in the late 1980s, a substantial body of research has been generated focusing on the development of FimH-targeting mannose-based anti-adhesion therapies. In this review we will discuss the design of different classes of these mannose-based compounds and their utility and potential as UPEC therapeutics. 相似文献
48.
Do Carmo Devaney Ribeiro de Oliveira Denys Ribeiro Barbosa Priscila Fernanda Pereira Godoi Natasha Mirella Inhã 《SILICON》2019,11(6):2961-2974
Silicon - Octa-(3-chloropropyl) octasilsesquioxane (SS) was functionalized with a PAMAM dendrimer (SP) and characterized by some spectroscopic techniques such as Fourier Transform Infrared, Nuclear... 相似文献
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