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Background Income and housing are pervasive social determinants of health. Subsidized housing is a prominent affordability mechanism in Canada; however, waitlists are lengthy. Subsidized rents should provide greater access to residual income, which may theoretically improve health outcomes. However, little is known about the health of tenants who wait for and receive subsidized housing. This is especially problematic for New Brunswick, a Canadian province with low population density, whose inhabitants experience income inequality, social exclusion, and challenges with healthcare access. Methods This study will use a longitudinal, prospective matched cohort design. All 4,750 households on New Brunswick’s subsidized housing wait list will be approached to participate. The survey measures various demographic, social and health indicators at six-month intervals for up to 18 months as they wait for subsidized housing. Those who receive housing will join an intervention group and receive surveys for an additional 18 months post-move date. With consent, participants will have their data linked to a provincial administrative database of medical records. Discussion Knowledge of housing and health is sparse in Canada. This study will provide stakeholders with a wealth of health information on a population that is historically under-researched and underserved.

Implicational tonoid logics and their relational semantics have been introduced by Yang and Dunn. This paper extends this investigation to implicational partial Galois logics. For this, we first define some implicational partial gaggle logics as special kinds of implicational tonoid logics called “implicational partial Galois logics.” Next, we provide Routley–Meyer-style relational semantics for finitary those logics.

This paper combines two classes of generalized logics, one of which is the class of weakly implicative logics introduced by Cintula and the other of which is the class of gaggle logics introduced by Dunn. For this purpose we introduce implicational tonoid logics. More precisely, we first define implicational tonoid logics in general and examine their relation to weakly implicative logics. We then provide algebraic semantics for implicational tonoid logics. Finally, we consider relational semantics, called Routley–Meyer–style semantics, for finitary those logics.

Determination of the purity of a substance traceable to the International System of Units (SI) is important for the production of reference materials affording traceability in quantitative measurements. Post-column isotope dilution using liquid chromatography-chemical oxidation-isotope ratio mass spectrometry (ID-LC-CO-IRMS) has previously been suggested as a means to determine the purity of organic compounds; however, the lack of an uncertainty budget has prevented assessment of the utility this approach until now. In this work, the previously published ID-LC-CO-IRMS methods have not only been improved by direct gravimetric determination of the mass flow of 13C-labelled spike but also a comprehensive uncertainty budget has been established. This enabled direct comparison of the well-characterised ID-LC-CO-IRMS method to quantitative nuclear magnetic resonance spectroscopy (qNMR) for purity determination using valine as the model compound. The ID-LC-CO-IRMS and qNMR methods provided results that were in agreement within the associated measurement uncertainty for the purity of a sample of valine of (97.1 ± 4.7)% and (99.64 ± 0.20)%, respectively (expanded uncertainties, k = 2). The magnitude of the measurement uncertainty for ID-LC-CO-IRMS determination of valine purity precludes the use of this method for determination of purity by direct analysis of the main component in the majority of situations; however, a mass balance approach is expected to result in significantly improved measurement uncertainty. Electronic supplementary material The online version of this article (10.1007/s00216-019-02116-2) contains supplementary material, which is available to authorized users.

Compound-specific amino acid carbon-isotope compositions have shown particular promise for elucidating dietary behaviors in complex environmental contexts, and may also be able to mitigate the effect of many of the limitations inherent to palaeodietary reconstructions. Here, we investigate the efficacy of compound-specific amino acid isotopic proxies in characterizing the consumption of different dietary protein sources using amino acid carbon-isotope compositions for humans and fauna from Rössberga (Early to Middle Neolithic), Köpingsvik (Mesolithic and Middle Neolithic), and Visby (Medieval Period), Sweden. We also assess the explanatory capabilities of an isotopic mixing model when used with essential amino acid carbon-isotope compositions of humans and local fauna. All three isotopic proxies distinguished among humans from the three sites consistently and informatively, and were able to enhance the broad interpretations made using bulk isotopic compositions. The mixing model palaeodietary reconstruction revealed considerable diversity in relative protein source contributions among individuals at both Köpingsvik and Visby. Comparing the mixing model for bulk carbon- and nitrogen-isotope compositions to the model for essential amino acid isotopic compositions further demonstrated the likelihood of underestimation and overestimation of marine protein consumption for both aquatic-dominant and mixed marine-terrestrial diets when using bulk isotopic compositions.

We report a methodology for the determination of the stable carbon absolute isotope ratio of a glycine candidate reference material with natural carbon isotopic composition using EA-IRMS. For the first time, stable carbon absolute isotope ratios have been reported using continuous flow rather than dual inlet isotope ratio mass spectrometry. Also for the first time, a calibration strategy based on the use of synthetic mixtures gravimetrically prepared from well characterised, highly (13)C-enriched and (13)C-depleted glycines was developed for EA-IRMS calibration and generation of absolute carbon isotope ratio values traceable to the SI through calibration standards of known purity. A second calibration strategy based on converting the more typically determined delta values on the Vienna PeeDee Belemnite (VPDB) scale using literature values for the absolute carbon isotope ratio of VPDB itself was used for comparison. Both calibration approaches provided results consistent with those previously reported for the same natural glycine using MC-ICP-MS; absolute carbon ratios of 10,649 × 10(-6) with an expanded uncertainty (k = 2) of 24 × 10(-6) and 10,646 × 10(-6) with an expanded uncertainty (k = 2) of 88 × 10(-6) were obtained, respectively. The absolute carbon isotope ratio of the VPDB standard was found to be 11,115 × 10(-6) with an expanded uncertainty (k = 2) of 27 × 10(-6), which is in excellent agreement with previously published values.

The decidability of the logic of pure ticket entailment means that the problem of inhabitation of simple types by combinators over the base { B, B′, I, W } is decidable too. Type-assignment systems are often formulated as natural deduction systems. However, our decision procedure for this logic, which we presented in earlier papers, relies on two sequent calculi and it does not yield directly a combinator for a theorem of $${T_\to}$$ . Here we describe an algorithm to extract an inhabitant from a sequent calculus proof—without translating the proof into another proof system.

We begin by discussing the history of quantum logic, dividing it into three eras or "lives." The first life has to do with Birkhoff and von Neumann's algebraic approach in the 1930's. The second life has to do with attempt to understand quan- tum logic as logic that began in the late 1950's and blossomed in the 1970's. And the third life has to do with recent developments in quantum logic coming from its connections to quantum computation. We discuss our own work connecting quantum logic to quantum computation (viewing quantum logic as the logic of quantum reg- isters storing qubits), make some speculations about mathematics based on quantum principles, and end by quickly describing the papers by the other authors contribut- ing to this special issue on "Quantum Logic Inspired by Quantum Computing." The overall aim of this issue is to show how work on this topic is leading to interesting new areas of logic.

One of the most dominant approaches to semantics for relevant (and many paraconsistent) logics is the Routley–Meyer semantics involving a ternary relation on points. To some (many?), this ternary relation has seemed like a technical trick devoid of an intuitively appealing philosophical story that connects it up with conditionality in general. In this paper, we respond to this worry by providing three different philosophical accounts of the ternary relation that correspond to three conceptions of conditionality. We close by briefly discussing a general conception of conditionality that may unify the three given conceptions.

Both I and Belnap, motivated the “Belnap-Dunn 4-valued Logic” by talk of the reasoner being simply “told true” (T), and simply “told false” (F), which leaves the options of being neither “told true” nor “told false” (N), and being both “told true” and “told false” (B). Belnap motivated these notions by consideration of unstructured databases that allow for negative information as well as positive information (even when they conflict). We now experience this on a daily basis with the Web. But the 4-valued logic is deductive in nature, and its matrix is discrete: there are just four values. In this paper I investigate embedding the 4-valued logic into a context of probability. Josang’s Subjective Logic introduced uncertainty to allow for degrees of belief, disbelief, and uncertainty. We extend this so as to allow for two kinds of uncertainty—that in which the reasoner has too little information (ignorance) and that in which the reasoner has too much information (conflicted). Josang’s “Opinion Triangle” becomes an “Opinion Tetrahedron” and the 4-values can be seen as its vertices. I make/prove various observations concerning the relation of non-classical “probability” to non-classical logic.

Symmetric generalized Galois logics (i.e., symmetric gGls) are distributive gGls that include weak distributivity laws between some operations such as fusion and fission. Motivations for considering distribution between such operations include the provability of cut for binary consequence relations, abstract algebraic considerations and modeling linguistic phenomena in categorial grammars. We represent symmetric gGls by models on topological relational structures. On the other hand, topological relational structures are realized by structures of symmetric gGls. We generalize the weak distributivity laws between fusion and fission to interactions of certain monotone operations within distributive supergGls. We are able to prove appropriate generalizations of the previously obtained theorems—including a functorial duality result connecting classes of gGls and classes of structures for them.

tAnGo is a large randomised trial assessing the addition of gemcitabine(G) to paclitaxel(T), following epirubicin(E) and cyclophosphamide(C) in women with invasive higher risk early breast cancer. To assess the safety and tolerability of adding G, a detailed safety substudy was undertaken. A total of 135 patients had cardiac, pulmonary and hepatic function assessed at (i) randomisation, (ii) mid-chemotherapy, (iii) immediately post-chemotherapy and (iv) 6 months post-chemotherapy. Skin toxicity was assessed during radiotherapy. No differences were detected in FEV1 or FVC levels between treatment arms or time points. Diffusion capacity (TLCO) reduced during treatment (P < 0.0001), with a significantly lower drop in EC-GT patients (P=0.02). Most of the reduction occurred during EC and recovered by 6-months post treatment. There was no difference in cardiac function between treatment arms. Only 11 patients had echocardiography/MUGA results change from normal to abnormal during treatment, with only five having LVEF < 50%. Transient transaminitis occurred in both treatment arms with significantly more in EC-GT patients post-chemotherapy (AST P=0.03, ALT P=0.003), although the majority was low grade. There was no correlation between transaminitis and other toxicities. Both treatment regimens reported temporary reductions in pulmonary functions and transient transaminitis levels. Despite these being greater with EC-GT, both regimens appear well tolerated.

Two types of trap, the BT Trap and PC(TM) pitfall cone trap, were evaluated against the most widely used method of sampling and sieving for their ability to detect low numbers of storage mites (Acarus siro, Tyrophagus longior and Lepidoglyphus destructor) in bulk oilseed rape, under UK maritime conditions. In addition, a synthetic lure (2-nonanone) was incorporated into the two types of trap to assess whether its presence improved trapping performance. The BT traps and PC traps were significantly more effective in detecting low numbers of mites of all species compared with sampling and sieving. The PC trap with synthetic lure was the most effective method. As the PC trap is already widely used for monitoring insects in cereal bulks in the UK, extending its application to include oilseed rape, and to detect mites, would be a logical and cost effective extension of its use.

We study an application of gaggle theory to unary negative modal operators. First we treat negation as impossibility and get a minimal logic system Ki that has a perp semantics. Dunn's kite of different negations can be dealt with in the extensions of this basic logic Ki. Next we treat negation as “unnecessity” and use a characteristic semantics for different negations in a kite which is dual to Dunn's original one. Ku is the minimal logic that has a characteristic semantics. We also show that Shramko's falsification logic FL can be incorporated into some extension of this basic logic Ku. Finally, we unite the two basic logics Ki and Ku together to get a negative modal logic K-, which is dual to the positive modal logic K+ in [7]. Shramko has suggested an extension of Dunn's kite and also a dual version in [12]. He also suggested combining them into a “united” kite. We give a united semantics for this united kite of negations.

Aeration is a promising alternative to the use of pesticides for the control of storage insects by cooling bulk grain, but its effectiveness against mite pests is neither fully understood nor optimised. For this reason, the productivity of three species of storage mites, Acarus siro, Lepidoglyphus destructor and Tyrophagus longior, was studied in a laboratory-based experiment at four combinations of temperature and humidity (10°C and 70% RH, 10°C and 80% RH, 20°C and 70% RH, 20°C and 80% RH) with and without an airflow (at 10 m3/h/tonne, equalling 2.5 l/s/tonne, in tubes containing 15 g of grain). This is the first time that a study has examined the three principal components of aeration separately from each other. The effect of these factors was different for each species. For A. siro, temperature was the most important factor, while airflow and humidity were of similar but lesser importance. For T. longior, temperature was more important than humidity, while the reverse was true for L. destructor. For these two species, airflow was the least important factor. The airflow decreased the productivity of L. destructor and T. longior but increased the productivity of A. siro. This increase in productivity confirms that, in practice, prevention of mite infestations, in particular A. siro, will require storage of grain at low temperature, relative humidity and moisture content.

A sample of covellite of particle size 45–90 µm was heated in air at 20°C min–1 in a simultaneous TG-DTA apparatus. The phase compositions of the products at various temperatures were determined quantitatively by XRD and FTIR. By 500°C, 5.8% of Cu2 O had formed, and this increased to a maximum of 44.8% at 585°C after which it decreased to zero by 750°C. 10% of CuO had formed by 680°C, and then steadily increased to 83.6% at 1000°C. 5.9% of CuO⋅CuSO4 was found at 610°C, and increased to a maximum value of 79% after which it decomposed completely by 820°C.

This paper explores allowing truth value assignments to be undetermined or "partial" (no truth values) and overdetermined or "inconsistent" (both truth values), thus returning to an investigation of the four-valued semantics that I initiated in the sixties. I examine some natural consequence relations and show how they are related to existing logics, including Łukasiewicz's three-valued logic, Kleene's three-valued logic, Anderson and Belnap's (first-degree) relevant entailments, Priest's "Logic of Paradox", and the first-degree fragment of the Dunn-McCall system "R-mingle". None of these systems have nested implications, and I investigate twelve natural extensions containing nested implications, all of which can be viewed as coming from natural variations on Kripke's semantics for intuitionistic logic. Many of these logics exist antecedently in the literature, in particular Nelson's "constructible falsity".

Many recent experiments have established that the Jahn-Teller (JT) effect plays a very important role in determining the properties of the C60 molecule. A review of the underlying theory developed by the Nottingham group is presented for cases in which distinct minima in the potential energy surface occur. This relates directly to the C60 molecule through the consideration of the T ⊗ h and H ⊗ h JT systems. When only linear coupling terms exist in the T ⊗ h system, the minima form a continuous trough of SO(3) symmetry and new methods must be used. Some details of these results are presented.

Circularly polarized x-ray radiation is attracting increasing interest as a tool for the characterization of the electronic, magnetic, and chiral properties of low-dimensional structures. Using circular light (with electric field vector parallel to the orbital plane), a dependence of the measured quantity by changing either the orientation of the light polarization or the magnetization is indicative of the existence of magnetic circular dichroism. It can be observed in x-ray absorption spectroscopy (XAS), in which the photon energy is scanned through an absorption threshold exciting a core electron into an unoccupied valence state using circularly polarized light. Synchrotron radiation sources have made this technique possible. It can also be observed in photo-emission spectroscopy from core and valence levels. Here we focus on magnetic circular x-ray dichroism (MCXD) in XAS as an element-specific tool to investigate magnetic properties of ultrathin films in situ. The application of magneto-optical sum rules enables the determination of the orbital and spin magnetic moments per atom from XAS spectra, as well as the easy magnetization direction.MCXD-based magnetometry in XAS is extensively used by measuring the L absorption edges of 3d-transition metals, where large intensity changes (up to 60%) of the L-edge white lines are observed upon reversal of either the sample magnetization or the light helicity. The high magnetic contrast obtained, combined with the elemental specificity of the technique, allows for the study of very dilute samples such as ultrathin films. We first concentrate on the selection rules governing MCXD in XAS.

The thermal decomposition of sodium ethyl xanthate (SEX) was used to compare the techniques of pyrolysis-gas chromatography-mass spectrometry (py-GC-MS), thermogravimetry-Fourier transform infrared spectroscopy (TG-FTIR), and TG-MS. In the py-GC-MS analysis, SEX was pyrolysed at 400°C in an inert atmosphere. Major gases evolved were carbon disulfide, diethyl sulfide, ethanol, and carbonyl sulfide. The TG of SEX exhibited a sharp mass loss at 201°C (42.3%) and a gradual mass loss at 217-325°C (20.8 %). The MS spectra of the evolved gases were complex due to overlapping of molecular, isotope, and fragment ion signals. Using the MS in selected ion monitoring mode, the major gases evolved were found to be carbon disulfide and carbonyl sulfide. The FTIR spectra of the evolved gases displayed vibrational frequencies due to alkanes, carbonyls, carbonyl sulfide, and carbon disulfide. From the analyses it was concluded that py-GC-MS provided unambiguous gas identification. Interpretation of the MS results was reliant on the py-GC-MS results, and the FTIR data was limited to identifying gases with very characteristic vibration frequencies.

A sample of chalcocite (Cu2S) of particle size 45–75 μm was heated in air at 10°C min−1 in a simultaneous TG-DTA apparatus. The phase compositions of the products at various temperatures were quantitatively determined by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and wet chemical analyses. Copper(II) sulfate, of amount 1.7% by mass, was observed at 435°C and increased rapidly in concentration to 56% at 570°C. From 570–670°C, there was a rapid decrease in CuSO4 content to 9.8% as the phase converted to CuSO4·CuO, with the CuSO4 not being detected at 775°C. From 435–570°C, Cu2O formed, but at a rather slower rate, reaching 47% at 570°C. The Cu2O level then decreased to 38% over the range 570–670°C. CuSO4·CuO was first detected at 570°C by FTIR, although it was not detected by XRD at this temperature. The content of this species reached 41% at 670°C, decreased to 24% at 775°C, and was not detected at 840°C. CuO first appeared at 670°C and rose steadily in concentration until at 840°C it was the only compound present.

The thermal decomposition of SEX in a nitrogen atmosphere was studied by coupled thermogravimetry-Fourier transform infrared spectroscopy (TG-FTIR), and by pyrolysis-gas chromatography-mass spectrometry (py-GC-MS). The TG curve exhibited two discrete mass losses of 45.8% and 17.8% respectively, at 200 and 257–364°C. The evolved gases identified as a result of the first mass loss were carbonyl sulfide (COS), ethanol (C2H5OH), ethanethiol (C2H5SH), carbon disulfide (CS2), diethyl sulfide ((C2H5)2S), diethyl carbonate ((C2H5O)2CO), diethyl disulfide ((C2H5)2S2), and carbonothioic acid, O, S, diethyl ester ((C2H5S)(C2H5O)CO). The gases identified as a result of the second mass loss were carbonyl sulfide, ethanethiol, and carbon disulfide. Hydrogen sulfide was detected in both mass losses by py-GC-MS, but not detected by FTIR. The solid residue was sodium hydrogen sulfide (NaSH). SEX was adsorbed onto activated carbon, and heated in nitrogen. Two discrete mass losses were still observed, but in the temperature ranges 100–186°C (7.8%) and 186–279°C (11.8%). Carbonyl sulfide and carbon disulfide were now the dominant gases evolved in each of the mass losses, and the other gaseous products were relatively minor. It was demonstrated that water adsorbed on the carbon hydrolysed the xanthate to cause the first mass loss, and any unhydrolysed material decomposed to give the second mass loss.

We give a set of postulates for the minimal normal modal logicK + without negation or any kind of implication. The connectives are simply ∧, ∨, □, ◊. The postulates (and theorems) are all deducibility statements ϕ ⊢ ψ. The only postulates that might not be obvious are $$\diamondsuit \varphi \wedge \square \psi \vdash \diamondsuit (\varphi \wedge \psi )\square (\varphi \vee \psi ) \vdash \square \varphi \vee \diamondsuit \psi $$ . It is shown thatK + is complete with respect to the usual Kripke-style semantics. The proof is by way of a Henkin-style construction, with “possible worlds” being taken to be prime theories. The construction has the somewhat unusual feature of using at an intermediate stage disjoint pairs consisting of a theory and a “counter-theory”, the counter-theory replacing the role of negation in the standard construction. Extension to other modal logics is discussed, as well as a representation theorem for the corresponding modal algebras. We also discuss proof-theoretic arguments.

Fullerene molecules adsorbed on surfaces often show macroscopic average distortions. As charged ions C 60 are known to be Jahn-Teller (JT) active, it is suggested that these distortions could be a manifestation of cooperative JT effects (CJTE) due to interactions between neighbouring fullerene ions. In order to understand the distortion properties it is necessary to take correlations between different distortions into account. However, this can’t easily be done in the mean field approximation usually used to describe the CJTE. We therefore propose an alternative procedure to describe 2D mesoscopic islands of C60 ions in which a pseudo vector spin $$\vec S$$ is evoked to represent degenerate JT-distorted states when the quadratic JT coupling is considered. This approach is analogous to methods used for 2D magnetic systems. We then use the differential operator technique in effective field theory within the Ising approach. We include the effects of weak surface interactions and dynamic motion between equivalent distortions via terms equivalent to anisotropy and a transverse field in magnetism respectively. For distortions to D 5d symmetry, we determine single site correlations as a function of temperature, the macroscopic average distortion describing a structural phase transition, and the isothermal response function. Phase diagrams are presented for relevant cases of the system parameters.

A sample of chalcocite of particle size 45–75 μm, has been oxidised in a TG-DTA apparatus at a heating rate of 10 deg·min−1 and the products at various temperatures characterised by XRD, SEM, FTIR and EPMA. This has enabled the events in the TG-DTA record to be assigned to specific chemical reactions, as well as the development of a full reaction scheme for the oxidation of chalcocite.

The general features of a numerical model, and of its extensions, for calculating the temperature and fluid velocity field in a three-dimensional workpiece undergoing deep penetration laser beam welding are described. In the current model, the deposition of power from the beam is represented by time-dependent boundary conditions on the equations of energy and momentum transfer. These boundary conditions are specified at each timestep on a surface whose configuration can change with time and upon which energy is deposited according to a specified power distribution. This model also includes the effects of the buoy-ancy force on the melt pool and of the surface tension gradient on the surface of the fluid. The coupled equations of energy, momentum transfer, and continuity combined with the time-dependent boundary conditions representing the keyhole and the moving boundaries of the workpiece are solved by using a specific implementation of the SIMPLE algorithm. The important features of the numerical methods used in the model are discussed. Isotherms and convection patterns calculated using the current model are presented, and their significance for predicting weldment properties is discussed. A significant result of the simulations is that they demonstrate the overwhelming influence of the keyhole vapor/liquid inter-face on fluid convection and conduction in deep penetration welding.

Recommendations for reporting of thermal analysis data relating to differential thermal analysis, differential scanning calorimetry, thermogravimetry and thermomechanical analysis were developed some two decades ago. Since that time there have been significant changes in the techniques, as well as a greater understanding of the effect of experimental variables on the results obtained from thermonalytical experiments. This paper reports on a preliminary review of the Recommendations by the Task Group established by the ICTAC Committee on Standardization to undertake their revision. Particular attention has been paid to the properties of the sample; control of the instrument variables; and the data acquisition and manipulation by computers.

Drop tube furnaces and thermal methods of analysis are techniques used to measure the ignition behaviour of reactive minerals such as Sulfides and coals. The use of the two techniques is discussed critically, and results obtained for pyrite and pyrrhotite have been compared. The values for ignition temperature are lower when determined by thermal methods relative to a drop tube furnace. Care must be exercised when comparing results as variables associated with the mineral such as its particle size, stoichiometry, and surface area, all influence its reactivity.

Four mineral sulfides typically found in the feed stock of a commercial nickel flash smelter, namely pyrite, violarite, pyrrhotite and pentlandite, were isolated from a primary and a supergene ore sample using magnetic separation. Relatively pure samples of pyrite, pyrrhotite and pentlandite were obtained, but violarite could only be upgraded to a 40–50% mixture with pyrite. These samples were characterized by chemical analysis, optical microscopy, Electron Probe Microanalysis (EPMA), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and Thermogravimetry-Differential Thermal Analysis (TG-DTA). Each sample was split into four fractions of particle size 20–45Μm, 45–75Μm, 75–90Μm and 90–125Μm. Ignition temperatures and extents of reaction were determined using an isothermal thermogravimeter, and the products were characterized by electron microscopy. Pyrite and violarite were found to be the most reactive to ignition, followed by pyrrhotite, with pentlandite being the least reactive. This order contradicts the results of other studies and various possible causes for this are discussed. The observed trend of increasing ignition temperature with increasing particle size was in agreement with previously published reports. The extent of reaction of each mineral was measured at increasing furnace preheat temperatures. These plots were correlated with the morphology of the products formed at the ignition temperature.

A series of pyrrhotites of various stoichiometries was synthesized and characterized, and fractionated into four particle size ranges. The ignition temperatures and extent of reaction were determined by a thermogravimetric method. These measurements enabled the effect of stoichiometry and particle size on the ignition temperature and extent of oxidation to be established. The trends observed in the ignition behaviour are consistent with the concept of sulfur evolution being the key to the initiation of the ignition reaction.

Applications philosophiques de la logique de la predication pertinente, mise au point par l'A., aux proprietes intrinseques et aux relations internes. Les proprietes intrinseques sont des predicats monadiques pertinents et les relations internes, des predicats polyadiques pertinents. L'A. compare sa theorie de la predication a celle de D. Lewis

A fairly simple generalization of the grade 2 fluid is described. However, unlike the grade 2 fluid, this fluid of differential type can accomodate extremely general viscometric data and still be consistent with commonly held ideas of energy dissipation and stability.

Recently developed projected Newton methods for minimization problems in polyhedrons and Cartesian products of Euclidean balls are extended here to general convex feasible sets defined by finitely many smooth nonlinear inequalities. Iterate sequences generated by this scheme are shown to be locally superlinearly convergent to nonsingular extremals $$\bar u$$ , and more specifically, to local minimizers $$\bar u$$ satisfying the standard second order Kuhn-Tucker sufficient conditions; moreover, all such convergent iterate sequences eventually enter and remain within the smooth manifold defined by the active constraints at $$\bar u$$ . Implementation issues are considered for large scale specially structured nonlinear programs, and in particular, for multistage discrete-time optimal control problems; in the latter case, overall per iteration computational costs will typically increase only linearly with the number of stages. Sample calculations are presented for nonlinear programs in a right circular cylinder in ?3.

We formulate a locally superlinearly convergent projected Newton method for constrained minimization in a Cartesian product of balls. For discrete-time,N-stage, input-constrained optimal control problems with Bolza objective functions, we then show how the required scaled tangential component of the objective function gradient can be approximated efficiently with a differential dynamic programming scheme; the computational cost and the storage requirements for the resulting modified projected Newton algorithm increase linearly with the number of stages. In calculations performed for a specific control problem with 10 stages, the modified projected Newton algorithm is shown to be one to two orders of magnitude more efficient than a standard unscaled projected gradient method.

We have measured the in-phase component of the low-frequency ac impedance of the dc current-induced intermediate state in indium-lead alloy wires. The specimens were mounted in a specific configuration that allowed a proper calculation of their dynamic resistances following the theory developed by Gauthier and Rochon, which is based on London's theory of the intermediate state. The theoretical values are considerably larger than our measurements, particularly near the critical current. We have modified the Gauthier-Rochon theory, to a first approximation, to take account of the Baird-Mukherjee model of the intermediate state and we find reasonably good agreement between the modified theoretical values and our observations.

In this paper two different formulations of Robinson's arithmetic based on relevant logic are examined. The formulation based on the natural numbers (including zero) is shown to collapse into classical Robinson's arithmetic, whereas the one based on the positive integers (excluding zero) is shown not to similarly collapse. Relations of these two formulations to R. K. Meyer's system R# of relevant Peano arithmetic are examined, and some remarks are made about the role of constant functions (e.g., multiplication by zero) in relevant arithmetic.

Naive implementations of Newton's method for unconstrainedN-stage discrete-time optimal control problems with Bolza objective functions tend to increase in cost likeN 3 asN increases. However, if the inherent recursive structure of the Bolza problem is properly exploited, the cost of computing a Newton step will increase only linearly withN. The efficient Newton implementation scheme proposed here is similar to Mayne's DDP (differential dynamic programming) method but produces the Newton step exactly, even when the dynamical equations are nonlinear. The proposed scheme is also related to a Riccati treatment of the linear, two-point boundary-value problems that characterize optimal solutions. For discrete-time problems, the dynamic programming approach and the Riccati substitution differ in an interesting way; however, these differences essentially vanish in the continuous-time limit.

The oxidative behaviour of synthetic millerite (Ni0.994S) has been studied by TG and DTA in a dynamic oxygen atmosphere (0.2 l min−1) over the temperature range 20–1000° (heating rate 10° min−1). EGA was carried out by a coupled mass spectrometer. The reaction products at various intermediate temperatures were characterized by X-ray powder diffractometry. A reaction sequence has been deduced, in which in the temperature range 550–700° complete oxidation of Ni0.994S had occurred with the formation of NiSO4, Ni3S2, NiO and possiblyα-Ni7S6. Between 700–800°, NiSO4 continued to be formed, whilst Ni3S2 andα-Ni7S6 were oxidised. Above 800°, NiSO4 decomposed to NiO, the latter being the only species evident above 800°.

A microcrystalline collagen hemostat (MCH) widely used in general surgery was tested in the control of bleeding from experimentally produced gastric ulcers. Five dogs had a gastrotomy and were given heparin. Using the standard "ulcer maker," three sets of three ulcers were made in the gastric mucosa of each animal. Blood from each ulcer was collected for a 5-min period to allow for stabilization of bleeding. MCH powder or slurry or no MCH was placed directly on one ulcer of each set in random order. The bleeding rate for the next 10 min was measured. Mean decrements in the bleeding rate for slurry MCH and dry MCH-treated ulcers were 87% and 81%, respectively, compared with 51% for controls, P less than 0.05. Twelve MCH-treated ulcers, but no control ulcer, stopped bleeding completely, P less than 0.01. Preliminary observations show that MCH slurry can be applied through an endoscope and may be hemostatically effective in man. MCH may have a role in the endoscopic control of gastrointestinal bleeding.