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This paper considers an epistemic interpretation of formal contexts, interpreting blank entries in the context matrix as absence of information, which is in agreement with the usual focus on the extraction of implications between attributes. After recalling non-classical connections induced by rough sets and possibility theory in formal concept analysis (FCA), and the standard theory of attribute implications in FCA, this paper presents the notion of disjunctive attribute implications, which reflect additional information that can be extracted from an epistemic context. We show that they can be computed like standard attribute implications from the complementary context. The paper also recalls the logic of classical attribute implications, relying on works pertaining to functional dependencies in database theory, and proposes a dual logic for disjunctive attribute implications. A method for extracting the latter kind of rules from a formal context is proposed, using a counterpart of pseudo-intents. Lastly, the paper outlines a generalization of both conjunctive and disjunctive attribute implications under the form of rules, with a conjunction of conditions in the body and a disjunction of conditions in the head, that hold in a formal context under the epistemic view. [ABSTRACT FROM AUTHOR]

For risk assessment to be a relevant tool in the study of any type of system or activity, it needs to be based on a framework that allows for jointly analyzing both unique and repetitive events. Separately, unique events may be handled by predictive probability assignments on the events, and repetitive events with unknown/uncertain frequencies are typically handled by the probability of frequency (or Bayesian) approach. Regardless of the nature of the events involved, there may be a problem with imprecision in the probability assignments. Several uncertainty representations with the interpretation of lower and upper probability have been developed for reflecting such imprecision. In particular, several methods exist for jointly propagating precise and imprecise probabilistic input in the probability of frequency setting. In the present position paper we outline a framework for the combined analysis of unique and repetitive events in quantitative risk assessment using both precise and imprecise probability. In particular, we extend an existing method for jointly propagating probabilistic and possibilistic input by relaxing the assumption that all events involved have frequentist probabilities; instead we assume that frequentist probabilities may be introduced for some but not all events involved, i.e. some events are assumed to be unique and require predictive – possibly imprecise – probabilistic assignments, i.e. subjective probability assignments on the unique events without introducing underlying frequentist probabilities for these. A numerical example related to environmental risk assessment of the drilling of an oil well is included to illustrate the application of the resulting method. [ABSTRACT FROM AUTHOR]

Abstract: Three-valued logics arise in several fields of computer science, both inspired by concrete problems (such as in the management of the null value in databases) and theoretical considerations. Several three-valued logics have been defined. They differ by their choice of basic connectives, hence also from a syntactic and proof-theoretic point of view. Different interpretations of the third truth value have also been suggested. They often carry an epistemic flavor. In this work, relationships between logical connectives on three-valued functions are explored. Existing theorems of functional completeness have laid bare some of these links, based on specific connectives. However we try to draw a map of such relationships between conjunctions, negations and implications that extend Boolean ones. It turns out that all reasonable connectives can be defined from a few of them and so all known three-valued logics appear as a fragment of only one logic. These results can be instrumental when choosing, for each application context, the appropriate fragment where the basic connectives make full sense, based on the appropriate meaning of the third truth-value. [Copyright &y& Elsevier]

There are several three-valued logical systems that form a scattered landscape, even if all reasonable connectives in three-valued logics can be derived from a few of them. Most papers on this subject neglect the issue of the relevance of such logics in relation with the intended meaning of the third truth-value. Here, we focus on the case where the third truth-value means unknown, as suggested by Kleene. Under such an understanding, we show that any truth-qualified formula in a large range of three-valued logics can be translated into KD as a modal formula of depth 1, with modalities in front of literals only, while preserving all tautologies and inference rules of the original three-valued logic. This simple information logic is a two-tiered classical propositional logic with simple semantics in terms of epistemic states understood as subsets of classical interpretations. We study in particular the translations of Kleene, Gödel, ᴌukasiewicz and Nelson logics. We show that Priest’s logic of paradox, closely connected to Kleene’s, can also be translated into our modal setting, simply by exchanging the modalities possibleand necessary. Our work enables the precise expressive power of three-valued logics to be laid bare for the purpose of uncertainty management.

Abstract: When conjunctively merging two belief functions concerning a single variable but coming from different sources, Dempster rule of combination is justified only when information sources can be considered as independent. When dependencies between sources are ill-known, it is usual to require the property of idempotence for the merging of belief functions, as this property captures the possible redundancy of dependent sources. To study idempotent merging, different strategies can be followed. One strategy is to rely on idempotent rules used in either more general or more specific frameworks and to study, respectively, their particularization or extension to belief functions. In this paper, we study the feasibility of extending the idempotent fusion rule of possibility theory (the minimum) to belief functions. We first investigate how comparisons of information content, in the form of inclusion and least-commitment, can be exploited to relate idempotent merging in possibility theory to evidence theory. We reach the conclusion that unless we accept the idea that the result of the fusion process can be a family of belief functions, such an extension is not always possible. As handling such families seems impractical, we then turn our attention to a more quantitative criterion and consider those combinations that maximize the expected cardinality of the joint belief functions, among the least committed ones, taking advantage of the fact that the expected cardinality of a belief function only depends on its contour function. [Copyright &y& Elsevier]

Abstract: There exist many simple tools for jointly capturing variability and incomplete information by means of uncertainty representations. Among them are random sets, possibility distributions, probability intervals, and the more recent Ferson’s p-boxes and Neumaier’s clouds, both defined by pairs of possibility distributions. In the companion paper, we have extensively studied a generalized form of p-box and situated it with respect to other models. This paper focuses on the links between clouds and other representations. Generalized p-boxes are shown to be clouds with comonotonic distributions. In general, clouds cannot always be represented by random sets, in fact not even by two-monotone (convex) capacities. [Copyright &y& Elsevier]

Abstract: There exist several simple representations of uncertainty that are easier to handle than more general ones. Among them are random sets, possibility distributions, probability intervals, and more recently Ferson’s p-boxes and Neumaier’s clouds. Both for theoretical and practical considerations, it is very useful to know whether one representation is equivalent to or can be approximated by other ones. In this paper, we define a generalized form of usual p-boxes. These generalized p-boxes have interesting connections with other previously known representations. In particular, we show that they are equivalent to pairs of possibility distributions, and that they are special kinds of random sets. They are also the missing link between p-boxes and clouds, which are the topic of the second part of this study. [Copyright &y& Elsevier]

Physically separated soil organic matter (SOM) fractions may take different functions in soil N dynamics. We studied the effect of long‐term organic matter (OM) management and different soil biological activity on the incorporation of N added with organic and mineral amendments into aggregate fractions and size density fractions. We applied 15N‐labeled sheep feces, urine, and mineral fertilizer to microplots installed in plots of conventional (CONMIN) and bio‐organic (BIOORG) cropping systems. Soil sampled 112 d after amendment was separated into macro‐, microaggregates, and microstructures. Aggregates were then fractionated into free light fraction (LF), intra‐aggregate particulate organic matter (iPOM), and the mineral‐associated organic matter fraction (MF). Of total soil N, 67% was contained in macroaggregates. Size density fractionation of aggregates revealed that about 60% of soil N was stored in MF while LF and iPOM contained together <3% of soil N. Despite long‐term OM input and higher soil biological activity in BIOORG than CONMIN the two soils did not differ in the distribution and content of N in aggregate and size density fractions. Recovery of 15N in nonfractionated soil ranged from 20% (SlurryF) to 25% (SlurryU) of originally applied 15N. The small macroaggregates were for each amendment the major sink (7–12% of applied 15N). In all aggregates and for all amendments, MF was the most important 15N sink, totally containing between 6.6% (SlurryF) to 11.6% (SlurryU) of applied 15N. Less than 1% of applied 15N was recovered in LF, and even less (<0.5%) in iPOM. The proportion of amendment‐derived N in aggregate fractions and in several size density fractions (LF, fine iPOM, MF) was higher for urine than for feces and mineral fertilizer. Recovery of urine‐derived 15N was greater in aggregate fractions of BIOORG than CONMIN soil. During dispersion of aggregates to obtain iPOM and MF, about 27% of total soil N and between 37 and 55% of 15N contained in non‐fractionated soil was lost, showing the importance of aggregation to protect N.

One of the challenges in constructing biological models involves resolving meaningful data patterns from which the mathematical models will be generated. For models that describe the change of mRNA in response to drug administration, questions exist whether the correct genes have been selected given the myriad transcriptional effects that may occur. Oftentimes, different algorithms will select or cluster different groups of genes from the same data set. A new approach was developed that focuses on identifying the underlying global dynamics of the system instead of selecting individual genes. The procedure was applied to microarray genomic data obtained from rat liver after a large single dose of methylprednisolone in 52 adrenalectomized rats. Twelve clusters of at least 30 genes each were selected, reflecting the major changes over time. This method along with isolating the underlying dynamics of the system also extracts and clusters the genes that make up this global dynamic for further analysis as to the contributions of specific mechanisms affected by the drug.

Seat belt assemblies are tested prior to vehicle crash tests in accordance with the UNECE R16 regulation. Thanks to these tests, global verifications of the restraint system performance are performed. Nevertheless, this common method is inadequate to analyse the local behaviour of seat belt components such as D-ring stability, because small variations of the dummy or the belt positions can create high perturbations in the test results. Besides, the cost of classical crash tests prevents planning test campaigns from focusing on the effect of these tiny variations. In this paper, an innovative test method is proposed to analyse webbing/D-ring/retractor subsystem of a seat belt assembly in a fully controlled manner. A test method is studied and evaluated by finite element analysis. An experimental bench is described and validated during a drop test campaign. Several load cases are described and a case of seat belt bunching phenomenon is reproduced.

Abstract: The compact representation of incomplete probabilistic knowledge which can be encountered in risk evaluation problems, for instance in environmental studies is considered. Various kinds of knowledge are considered such as expert opinions about characteristics of distributions or poor statistical information. The approach is based on probability families encoded by possibility distributions and belief functions. In each case, a technique for representing the available imprecise probabilistic information faithfully is proposed, using different uncertainty frameworks, such as possibility theory, probability theory, and belief functions, etc. Moreover the use of probability–possibility transformations enables confidence intervals to be encompassed by cuts of possibility distributions, thus making the representation stronger. The respective appropriateness of pairs of cumulative distributions, continuous possibility distributions or discrete random sets for representing information about the mean value, the mode, the median and other fractiles of ill-known probability distributions is discussed in detail. [Copyright &y& Elsevier]

AbstractSome safety belt D-rings lead to a non-systematic instability; the webbing, which should scroll without hindrance through the D-ring, laterally shifts, bunches and produces the overturning of the ring. To expertise this so-called seat belt bunching phenomenon, finite element numerical simulations are undertaken at a mesoscopic scale. A new shell element is developed to simulate seat belt fabric behaviour. To support the finite element mesoscopic scale model, several tests on components are conducted and new test methods are focused on the seat belt behaviour. To correlate the model, an innovative fixture is used to reproduce the dynamic motion of the seat belt through the D-ring. To expertise the phenomenon, frontal sled tests are performed and a correlated model has been developed that allows to assess the instability phenomenon.

A series of cis and trans Fe(II) complexes containing the diphosphine ligand PNP (where PNP is bis((diethylphosphino)methyl)methylamine) have been prepared and isolated. These include cis-[Fe(PNP)2(CH3CN)2](BF4)2 (3), cis-[Fe(PNP)2(CH3CN)(CO)](BF4)2 (4), trans-[Fe(PNP)(dmpm)(CH3CN)2](BF4)2 (5), trans-Fe(PNP)(dmpm)Cl2 (6), trans-[Fe(PNP)(dmpm)(CO)Cl]2[FeCl4] (7), trans-HFe(PNP)(dmpm)Cl (8), and trans-[HFe(PNP)(dmpm)(CH3CN)]BPh4 (9) (where dmpm is bis(dimethylphosphino)methane). In addition, the cations trans-[HFe(PNP)(dmpm)(CO)]⁺ (10) and trans-[(H2)Fe(PNP)(dmpm)(H)]⁺ (11) have been observed in solution. These complexes all possess a pendant base that bridges the two phosphorus atoms of the PNP ligand. A cis geometry is observed for those complexes containing two PNP ligands, whereas a trans geometry is observed for the complexes containing one PNP ligand and one dmpm ligand. The molecular structures of cis-[Fe(PNP)2(CH3CN)(CO)](BPh4)2 and trans-[HFe(PNP)(dmpm)(CH3CN)]BPh4 have been confirmed by X-ray diffraction studies. Protonation of 5, 7, and 10 occurs at the nitrogen atom of the PNP ligand, and pKa values are reported for the corresponding protonated complexes. The formation of the dihydrogen complex [trans-[(H2)Fe(PNP)(dmpm)(H)]⁺ and the protonated PNHP complex trans-[HFe(PNHP)(dmpm)(CO)]²⁺ demonstrate that intramolecular heterolytic cleavage of the dihydrogen ligand can be controlled by varying the nature of the ligand trans to the incipient dihydrogen ligand.

Four new rhodium complexes, [Rh(depx)2](CF3SO3), [(H)2Rh(depx)2](CF3SO3), [HRh(depx)2(CH3CN)](CF3SO3)2, and HRh(depx)2 (where depx = α,α‘-bis(diethylphosphino)xylene), have been synthesized and characterized. The pKa values of [(H)2Rh(depx)2]⁺ (30.6 ± 0.3) and [HRh(depx)2(CH3CN)]²⁺ (11.5 ± 0.4) in acetonitrile were determined by equilibrium reactions with appropriate bases. The hydride donor ability of [(H)2Rh(depx)2]⁺ (71.6 ± 1.0 kcal/mol) was determined by the heterolytic cleavage of hydrogen by [HRh(depx)2(CH3CN)]²⁺ to form [(H)2Rh(depx)2]⁺ in the presence of thioacetamide or benzamide. These equilibrium measurements, the half-wave potentials for the Rh(+1/0) and Rh(0/−1) couples of [Rh(depx)2]⁺, and the reversible one-electron oxidation of HRh(depx)2 (all measured at 22 ± 1.5 °C) were used to establish nine heterolytic and homolytic bond-dissociation free energies in acetonitrile. From these relationships, and those established previously for analogous cobalt and platinum complexes, we conclude that the homolytic bond-dissociation free energies of six-coordinate dihydride species are approximately 2 kcal/mol less than those of the corresponding five-coordinate monohydride species derived by deprotonation. Similarly, the pKa values of six-coordinate dihydride complexes are approximately 2 units lower than the corresponding five-coordinate species formally derived by homolytic bond cleavage.

Background & Aims: The Patient Assessment of Upper Gastrointestinal Disorders-Quality of Life (PAGI-QOL) has been developed and validated to assess quality of life in gastroesophageal reflux disease, dyspepsia, and gastroparesis. The aim of this work was to assess responsiveness of the PAGI-QOL to clinical changes and provide guidance for the interpretation of score changes. Methods: The analysis was based on 2 observational multicenter, longitudinal, 8-week observation studies, one in the United States and one in 5 European countries. The Overall Treatment Effect scale completed by patients and clinicians at 8 weeks was used to define groups of improved, worsened, and stable patients. Responsiveness was assessed by describing the change in PAGI-QOL scores for each of these groups, comparing these changes over time, and calculating effect sizes and standardized response means. These data were used to define the minimal clinically important difference. Results: A total of 1736 patients with upper gastrointestinal disorders were analyzed. High sensitivity to change over time was demonstrated, with effect sizes and standardized response means in improved patients for the PAGI-QOL total score ranging from 0.79-1.41. A change of 0.4 for the PAGI-QOL total score might be considered as the minimal clinically important difference when comparing pretreatment and post-treatment PAGI-QOL total scores. Conclusions: The PAGI-QOL questionnaire is a responsive and clinically relevant instrument for assessing quality of life in patients with upper gastrointestinal disorders.

Background & Aims: Determining clinically meaningful change of patient-reported outcome measures is important for evaluating effectiveness of treatments for gastrointestinal (GI) diseases. This study evaluates responsiveness of the Patient Assessment of Gastrointestinal Disorders-Symptom Severity Index (PAGI-SYM) in gastroesophageal reflux disease (GERD) and dyspepsia. Methods: The PAGI-SYM was based on a review of the published literature and interviews with patients and clinicians. Items were developed to be linguistically and culturally appropriate for multicountry studies. The PAGI-SYM includes 6 subscales: heartburn/regurgitation, fullness/early satiety, nausea/vomiting, bloating, upper abdominal pain, and lower abdominal pain. Subjects with GERD (n = 810) or dyspepsia (n = 767) participated in this multicountry, observational study. All subjects completed the PAGI-SYM, a global symptom relief questionnaire, and a measure of patient-rated change in GI-related symptoms, the Overall Treatment Effect (OTE) scale. Responsiveness was evaluated at 8 weeks by comparing groups by disease, symptom relief, and OTE (improved, stable, and worsened). Results: Subjects reporting symptom relief reported significantly lower (better) PAGI-SYM scores than those reporting no symptom relief (P < 0.0001 to P < 0.0005). Subjects with improvements in overall GI symptoms exhibited significant decreases in PAGI-SYM subscale scores compared with those who remained the same or worsened (all P values < 0.0001). Effect sizes ranged from 0.21-1.28, and standard errors of measurement ranged from 0.29-0.63, depending on subscale and disease sample. Conclusions:The PAGI-SYM is a brief symptom severity instrument that measures common GI symptoms. Results suggest that the PAGI-SYM is responsive and sensitive to change in clinical status in subjects with GERD or dyspepsia.

A systematic study was carried out in order to characterise a DC pulsed discharge used for the treatment of polystyrene thin films. The energy which is injected into plasma can be modulated while exploiting the discharge time (τ), the afterglow duration time (tag) and the treatment duration time (tt). The variations of the macroscopic properties of surface were monitored by measurement of the contact angle and we correlated these results of wettability with the way in which energy is distributed. The experimental results showed that the surface treatment was better (the largest wettability) for the smallest values of τ(2 µs) and largest times of tag(0.1 s). A sensitivity of the treatment to the distribution of energy was highlighted, and it is through this study that we will put forth assumptions on the species responsible for the treatment.

[HPt(EtXantphos)2](PF6) (where EtXantphos is 9,9-dimethyl-4,5-bis(diethylphosphino)xanthene) can be prepared by the reduction of Pt(COD)Cl2 (where COD is 1,4-cyclooctadiene) with hydrazine in the presence of 2 equiv of the diphosphine ligand followed by exchange of Cl^- with PF6^-. Deprotonation of [HPt(EtXantphos)2](PF6) (pKa = 27.3 in acetonitrile) leads to the formation of Pt(EtXantphos)2, which has been characterized by an X-ray diffraction study. Pt(EtXantphos)2 has a distorted tetrahedral geometry. The average chelate bite angle is 108.2°, and the dihedral angle between the two planes formed by the phophorus atoms of each diphophine ligand and platinum is 80.4°. Protonation of [HPt(EtXantphos)2]⁺ results in the formation of [(H)2Pt(EtXantphos)2]²⁺, which has a pKa of 6.8 in acetonitrile. Oxidation of Pt(EtXantphos)2 with ferrocenium tetrafluoroborate produces [Pt(EtXantphos)2]²⁺. [Pt(EtXantphos)2]²⁺ undergoes two reversible one-electron reductions (E1/2(II/I) = −0.81 V versus ferrocene and E1/2(I/0) = −0.97 V), and [HPt(EtXantphos)2]⁺ undergoes a reversible one-electron oxidation (E1/2(II/III) = +0.23 V). These half-wave potentials and the pKa values of [HPt(EtXantphos)2]⁺ and [(H)2Pt(EtXantphos)2]²⁺ have been used to calculate five additional homolytic and heterolytic bond-dissociation free energies for these two hydride species and for [HPt(EtXantphos)2]²⁺. The extensive thermodynamic characterization of this hydride system provides useful insights into the factors controlling the reactivity of these complexes.

The complexes M(PNP)2²⁺ (M = Pd, Pt, PNP = Et2PCH2N(Me)CH2PEt2) were synthesized by addition of PNP to Pd(CH3CN)4(BF4)2 and (COD)PtCl2, respectively. Pd(PNP)2 was synthesized by reaction of Pd(PNP)2²⁺ with H2 and tetramethylguanidine (TMG) in CH3CN. The thermodynamic hydride donor ability, ΔG°H^-, for HPt(PNP)2⁺ (54.7 kcal/mol) was measured by heterolytic cleavage of hydrogen in the presence of NEt3 in CH3CN. The hydride donor ability of HPd(PNP)2⁺ (51.1 kcal/mol) was determined by measuring the equilibrium constant for direct hydride transfer to Pt(PNP)2²⁺. The M(II) complexes undergo reversible, two-electron reductions in benzonitrile. The measured reduction potentials were used in a thermodynamic cycle to estimate pKa values of 22.1 and 27.6 for deprotonation of HPd(PNP)2⁺ and HPt(PNP)2⁺, respectively. The palladium hydride has an acidity equal to that of the nickel hydride and is a better hydride donor than both the nickel and platinum analogues. This shows that it is possible for transition metal hydrides to act simultaneously as both acids and hydride donors.

The Rh(I) and Rh(III) hydrides HRh(dppb)2 and [HRh(dppb)2(NCCH3)](BF4)2 (where dppb is 1,2-(bis(diphenylphosphino)benzene) have been prepared, and a structural study of [HRh(dppb)2(NCCH3)](BF4)2 has been completed. The latter complex is an octahedral complex with a trans arrangement of the hydride and acetonitrile ligands. A pKa value of 9.4 was measured for this complex by equilibration of [Rh(dppb)2](BF4) with 4-bromoanilinium tetrafluoroborate in acetonitrile. [Rh(dppb)2](BF4) reacts with H2 in the presence of Pt(dmpp)2, which acts as a base, to form HRh(dppb)2 and [HPt(dmpp)2](BF4) (where dmpp = 1,2-bis(dimethylphosphino)propane). An equilibrium constant of 0.42 ± 0.2 was measured for this reaction. Using this equilibrium measurement and a thermodynamic cycle, the hydride donor ability (ΔG°H-) of HRh(dppb)2 was determined to be 34 kcal/mol. This value indicates that HRh(diphosphine)2 complexes are powerful hydride donors. Similarly the pKa value of HRh(dppb)2 was calculated to be 35 from a thermodynamic cycle that included the potential of the Rh(I/−I) couple (E1/2 = −2.02 V vs ferrocene). These results combined with results from the literature suggest the following order of hydricity for five-coordinate, 18-electron hydrides:  second row > third row > first row. Similarly an acidity order of second row ≥ first row > third row is deduced.

The aim of this work was to assess to which extent organic farming practices would affect the accumulation of total and available phosphorus (P) in a cropped soil in comparison to conventional practices. In order to achieve this, soil samples were taken from a long-term field trial comparing a non-fertilised control (NON), two conventionally cultivated treatments (MIN, CON), and two organically cultivated treatments (ORG, DYN). Soil samples were taken from each treatment at two depths (0-20 and 30-50 cm) before starting the field trial (1977) and at the end of every three crop rotations (1984, 1991 and 1998). They were then analysed for total P (Pt), total inorganic P (Pi), total organic P (Po) and isotopically exchangeable Pi. After 21 years, the average P input-output budget reached -20.9 kg P ha−1a−1for NON, -7.8 for DYN, -5.7 for ORG, -5.0 for MIN and +3.8 for CON. Total P, Pias well as the amount of Piisotopically exchangeable within 1 minute (E1) were positively correlated to the P budget. Comparison between P budget and Ptin the top- and subsoils of the fertilised treatments suggested a net transfer of P from the 0–20 to the 30–50 cm layers between 13 and 26 kg P ha−1a−1during the first rotation and between 3 and 12 kg P ha−1a−1during the second rotation. During the third rotation a net upward movement of P from the subsurface to the topsoil ranging between 3.7 and 10.5 kg P ha−1a−1was estimated. In the topsoil, E1decreased from an initial value of 12 mg P kg−1to 11 in CON, 8 in MIN, 6 in ORG, 5 in DYN and 2 in NON after 21 years. In the subsoil, E1increased from an initial value of 2 mg P kg−1to 4 in MIN, ORG, DYN and NON and to 6 in CON. These results show that, with the exception of NON, all treatments had still an adequate level of available P after 21 years of trial and that, in this low to moderately P sorbing soil, an equilibrated input-output budget allows to maintain P availability at a constant level. In the organic systems, yields have so far partly been attained at the expense of soil reserves or residual P from earlier fertiliser applications.

A linear free-energy relationship exists between the half-wave potentials of the (II/I) couples of Ni(diphosphine)2 complexes and the hydride donor ability (ΔG°H^{−) of the corresponding [HNi(diphosphine)2]+ complexes. A similar correlation is observed between the half-wave potentials of the (I/0) couples of Ni(diphosphine)2 complexes and the pKa values (or ΔG°H+) of the corresponding [HNi(diphosphine)2]+ complexes. As a result, it is possible to use the potentials of these two couples to predict the free energies of all three Ni−H bond cleavage reactions, ΔG°H+, ΔG°H•, and ΔG°H−, for this class of nickel complexes. The molecular structures of Ni(Et2PCH2CH2PPh2)2 and Ni(Ph2PCHCHPPh2)2 were determined by single-crystal X-ray diffraction studies.}

Simple, reactive amphiphilic molecules were prepared by condensation of perfluorooctylethyl alcohol with elaidic, oleic, and linoleic acids. The fluorinated, unsaturated esters were found to be surface active in polyester and urethane-modified alkyd coatings. In addition, they function much like typical drying oils used in these coatings through oxidative cross-linking. The surfaces of the coatings were examined by contact angle goniometry and X-ray photoelectron and time-of-flight secondary ion mass spectroscopy. The solution properties of these fluorinated derivatives were studied by measurement of surface tension isotherms, vapor pressure osmometry, and variable temperature ¹⁹F NMR spectroscopy in n-butyl acetate solution. Analysis of the data revealed that aggregation is occurring at low (&lt;10^-1 mol/L) solute concentration. The aggregates were small and ranged between 3 and 7 monomer units. Analysis of the variable temperature ¹⁹F NMR data for the linoleic acid ester gave thermodynamic parameters for aggregation of %@mt;sys@%Δ%@ital@%G%@rsf@%%@/xs;55;%lnwidth@%°%@/xs;63;(%lnwidth-x55)@%%@mh;-x63@%%@sb@%a%@sbx@%%@mx@% ≈ −4.30 ± 0.2 kcal/mol, Δ%@mt;sys@%%@ital@%H%@rsf@%%@/xs;55;%lnwidth@%°%@/xs;63;(%lnwidth-x55)@%%@mh;-x63@%%@sb@%a%@sbx@%%@mx@% ≈ 6.11 ± 2 cal/mol, and Δ%@mt;sys@%%@ital@%S%@rsf@%%@/xs;55;%lnwidth@%°%@/xs;63;(%lnwidth-x55)@%%@mh;-x63@%%@sb@%a%@sbx@%%@mx@% ≈ 15.7 ± 0.8 cal/(mol·K).

Based on a real-world industrial case-study, the DIDOM project investigates new forms of industrial production strategies, having a dual trade-project structure, and involving distributed decisions, with a view to specify realistic decision-support tools adapted to such contexts. After introducing some features of multi-project management and our methodology, the paper presents the main results achieved in two main areas: on the one hand, the crucial role, in the decision process, of a workplan involving temporal landmarks, its construction and its repair, and, on the other hand, the cooperation procedures appearing in a distributed decision framework.

Tracking malfunctions in reasonable time on an engine dyno test bench is becoming too complex for human beings. An online diagnosis system is being studied for this purpose. Knowledge about possible effects of a malfunction on an attribute and (imprecise) observations are modelled by possibility distributions. Any kind of attributes (binary, numerical, . . .) is allowed. The paper assumes the single-fault hypothesis. Two main indices are respectively used for respectively detecting i) the malfunctions whose presence is more or less inconsistent with the available observations and ii) the malfunctions (most of) all the expected effects of which have been more or less certainly observed (using abduction).

The radiopacity of intermediate restorative materials should be sufficient to enable the clinician to distinguish the material from normal and decalcified tooth structure. The purpose of this study was to determine the relative radiopacities of intermediate restorative materials, including a newly introduced high-viscosity, self-cured, condensable glass ionomer material. Radiographs were made of six intermediate restorative materials: two reinforced zinc oxide-eugenol materials (IRM and Zinroc), a conventional glass ionomer material (Ketac-fil), a synthetic resin material (Cavit), a eugenol-free zinc oxide material (Tempit), and a new, general-purpose, condensable glass ionomer material (Fuji IX-GP). Optical density was measured using a densitometer. The optical density of dentin and enamel were used for radiographic comparison. Statistical analysis revealed significant differences among materials: Cavit = IRM = Tempit > Zinroc = Fuji IX-GP > Ketac-fil = enamel > dentin (where > indicates a statistical difference at p < or = 0.05). Although not as radiopaque as some other intermediate materials tested, the radiopacity of Fuji IX-GP appears sufficient to aid diagnosis.

Les bactériémies à Campylobacterspp. sont des infections sévères avec une mortalité élevée (15–28 %). Cependant, une grande proportion de patients est traitée de façon inappropriée dans les séries publiées. Les facteurs favorisants liés à l’hôte sont mal connus, notamment les thérapies immunosuppressives.

The effects of growth hormone (GH) treatment on renal sodium sulfate cotransport (NaSi-1) were studied in adult (9-10 months) and old (22-23 months) male Fischer 344 rats. All animals received twice-daily s.c. injections of recombinant human GH (hGH; 4 mg/kg) for up to 6 days. Animals were sacrificed by exsanguination on days 0, 1, 2, 3, 4, 5, and 6. Kidneys were removed, and kidney cortex was trimmed immediately and used for RNA and membrane preparations. Plasma hGH concentrations were significantly lower in old rats during the hGH treatment (P <.05). Insulin-like growth factor-I (IGF-I) levels were significantly increased and remained stable after day 2 of hGH treatment in both age groups (P <.05). There was no significant difference in plasma IGF-I levels between age groups. Plasma IGF-I binding protein 3 (IGFBP-3) concentrations were significantly higher in 9- to 10-month-old rats compared with that in 22- to 23-month-old animals (P <.001). There were no significant differences in plasma IGFBP-3 concentrations between days of hGH treatment. The NaSi-1 mRNA levels were significantly lower in 22- to 23-month-old rats compared with that in 9- to 10-month-old animals (P <.001). The NaSi-1 mRNA levels were significantly increased on days 2 and 3 of hGH treatment (P <.05) and then gradually decreased to the control value. The NaSi-1 protein levels in old animals (22-23 months) were also significantly lower than that of 9- to 10-month-old animals and were significantly increased from day 2 of hGH treatment, reaching a maximum level on day 3 or 4 and then returning to the baseline level in both age groups. From these results, it was concluded that 1) NaSi-1 mRNA and protein levels are lower in old animals and increase in both adult and aged rats after hGH treatment, 2) plasma IGF-I levels are similar in adult and aged rats and increase after hGH treatment, and 3) plasma IGFBP-3 levels are lower in old rats and remain unchanged after hGH treatment.

Muscle wasting and excessive fat deposition are side effects attendant to chronic corticosteroid treatment. Corticosteroid immunosuppression is necessary in circumstances such as transplantation. Pharmacokinetic/pharmacodynamic (PK/PD) modeling was used to help elucidate the relationships between the events in the molecular cascade that result in muscle wasting and fat deposition by corticosteroids. Specifically, the relationships for receptor/gene-mediated effects that result in increased glutamine synthetase (GS) activity in skeletal muscle were quantitatively analyzed after an i.v. bolus dose of 50 mg/kg methylprednisolone in male adrenalectomized Wistar rats. Profiles of methylprednisolone pharmacokinetics, glucocorticoid receptor density, and its mRNA, GS mRNA, and GS activity in gastrocnemius muscles were determined. The results were used to develop PK/PD models using differential equations in the ADAPT II program. Two indirect response models were tested for the dynamics of glucocorticoid receptor mRNA regulation by activated steroid/receptor complex. Both reduction in message synthesis and message destabilization may be involved but with some tissue specificity. The recovery of active receptor after down-regulation is biphasic. The initial recovery may involve receptor recycling from the nucleus, whereas the later phase may involve de novo synthesis of new receptor protein. The nuclear events and GS mRNA/GS induction in rat skeletal muscle show sequential relationships for each component for corticosteroid actions. The PK/PD models provide mechanism-based methods of quantifying complex processes in receptor/gene-mediated enzyme induction featuring the characteristics of time delay and possible nonlinearity in intact tissues.

The state of a fuzzy system can be described by fuzzy numbers. For a theory of fuzzy systems to be realistic, weak definitions of reachability, observability, stability must be established. Such concepts stem from basic notions of equality of numbers, and convergence of sequences of numbers. This paper discusses several points of view for natural extensions of these notions to fuzzy numbers. Relaxed versions of equality and convergence are provided. They account for the fact that membership functions of fuzzy numbers can never be precisely estimated.

This short communication describes a possible application of fuzzy set theory to information retrieval systems. The aim is to improve the performances of such systems, namely the quality of selection, when all-or-nothing queries are unable to select a sufficiently small subset of items. The main idea is to rank the elements of this selected subset in term of the overall compatibility of each item with a fuzzy description expressing the user's preferences. This description is assumed of a semantic nature, i.e. with numerical features, as opposed to structural or syntactic ones. The latter features may however be used to select a subset of admissible items in a first step. Then, in a second step, the fuzzy description is simply built through a man-machine dialog. The paper focuses on this second step ; it deals with the representation of fuzzy specifications and their combination for the purpose of defining a compatibility index between the query and the objects stored in the data base.

Stems of wheat (Triticum aestivumL.) accumulate water‐soluble carbohydrates (WSC) during the first 3 wk after anthesis. These reserves can later contribute to grain filling. Two spring wheat genotypes (‘Kolibri’ and breeding line D) were tested in growth chambers to determine if they differ in the accumulation of WSC components and in the activation of sucrose:sucrose fructosyltransferase (SST) in stem tissue. Concentration of CO2was supplied at 1000 or 300 μL CO2L−1after anthesis to alter photosynthate production. The WSC accumulation in the penultimate internode during the first 18 d post anthesis (DPA) was substantially higher in Genotype D than in Kolibri. The WSC accumulation up to 7 DPA was due to increases in hexoses and sucrose. Sucrose concentration was initially lower in Kolibri than in Genotype D, but increased to a comparable level for both genotypes and both CO2treatments. Fructan synthesis was initiated at 7 DPA. At 18 DPA, fructan was the dominant component of WSC. Under both CO2, treatments Genotype D accumulated substantially higher fructan concentrations than Kolibri. In a second experiment, induction of SST activity was observed during the first 9 DPA in the penultimate internode of plants grown at 1000 and 200 μL CO, L−1. There was a positive relationship between sucrose concentration and in vivo SST activity, suggesting that sucrose induced SST activity; however, Kolibri exhibited a much lower SST activity at given sucrose concentration. Thus, the low fructan synthesis of Kolibri is associated with an initial lower sucrose concentration and with a less effective activation of SST by sucrose.

Several forms of optimal least-squares k-step-ahead predictors are presented. These forms depend on the type of formulation : single step, multi step, step-recursive formulations; minimum variance and constrained minimum variance predictions; non adaptive and self-tuning predictors. Several variants of these forms are presented for ARIMAX process models. Both SISO and MIMO systems are considered.

We have studied the hemodynamic effects of an intravenous single dose of nitroglycerin in 13 patients with secondary pulmonary hypertension and Cor Pulmonale, during the acute course of respiratory failure and under assisted ventilation. We observed a significant decrease in systolic, diastolic and mean pulmonary arterial pressures, and in pulmonary resistance and systolic right ventricular work index, without any change in right or left pre-loads. The systolic arterial pressure decreased slightly, without any change in cardiac index or diastolic pressure. The arterial and mixed venous oxygen contents, and the pulmonary shunting (Qs/Qt) were unchanged. These results suggest that nitroglycerin may be a useful therapy in patients in the acute stages of pulmonary hypertension resulting from chronic lung disease and under assisted ventilation. In addition, the lack of change in cardiac index, intrapulmonary shunting and oxygen content suggests that this decrease in pulmonary resistance is not linked with any deleterious effect in oxygen transfer.

This study determined the pattern of expression of the c-fosoncogene in endometrium from pregnant and cyclic gilts. A transcript of the expected 2.2-kb size for the c-fosmRNA was detected in porcine endometrium from cyclic and pregnant gilts. Expression of endometrial c-fosmRNA was not different for Days 0, 5, 10, 15, or 18 cyclic or pregnant gilts. However, expression of c-fosmRNA was greater on Day 12 of pregnancy compared to Day 12 of the estrous cycle. Furthermore, expression of c-fosmRNA was related to developmental stages when pig conceptuses secrete estradiol, the primary determinant for maternal recognition of pregnancy. Throughout the estrous cycle and early pregnancy, immunoreactive fos protein was localized to the glandular and surface epithelial cells as well as myometrial cells. Results of this study indicate that endometrial expression of c-fosmRNA increases on Day 12 of pregnancy, coinciding with the establishment of maternal recognition of pregnancy in pigs.