Diophantine Undecidability of Holomorphy Rings of Function Fields of Characteristic 0

Let $K$ be a one-variable function field over a field of constants of characteristic 0. Let $R$ be a holomorphy subring of $K$, not equal to $K$. We prove the following undecidability results for $R$: If $K$ is recursive, then Hilbert's Tenth Problem is undecidable in $R$. In general, there exist $x_1,...,x_n \in R$ such that there is no algorithm to tell whether a polynomial equation with coefficients in \Q(x_1,...,x_n) has solutions in $R$.Comment: This version contains minor revisions and will appear in Annales de l Institut Fourie

Pain management skills of regional nurses caring for older people with dementia: a needs analysis

An exploratory survey of the pain management education needs of 197 nurses working with older people with dementia was undertaken in a regional area of Queensland, Australia. The analysis indicated that nurses in this setting might not have the knowledge base to manage pain effectively; and that respondents have essentially negative perceptions of the availability and appropriateness of current pain management education programs. Consistent with non-metropolitan nurses generally, respondents expressed a preference for pain management education that had a significant face-to-face component allied with ongoing mentorship and support on completion of the program. The obstacles to attending such programs were also typical of the problems facing regional and rural nurses throughout Australia. These were identified as inability to pay for courses; lack of information on what is available; distance to travel to education; and a perceived lack of employer support due to an inability to replace those staff attending education. Positive aspects include the degree to which participants were responsive and interested in dementia pain management and their access to, and acceptance of, non-medical pain therapies. The findings suggest a definite need for a dementia pain management program for aged care nurses, specifically tailored to their needs and to the constraints of the regional practice setting

Interactions between hydrated cement paste and organic acids: Thermodynamic data and speciation modeling

International audienceInteractions of short-chain organic acids with hydrated cement phases affect structure durability in the agro-food and nuclear waste industries but can also be used to modify cement properties. Most previous studies have been experimental, performed at fixed concentrations and pH, without quantitatively discriminating among polyacidity effects, or complexation and salt precipitation processes. This paper addresses such issues by thermodynamic equilibrium calculations for acetic, citric, oxalic, succinic acids and a simplified hydrated CEM-I. The thermodynamic constants collected from the literature allow the speciation to be modelled over a wide range of pH and concentrations. Citric and oxalic had a stronger chelating effect than acetic acid, while succinic acid was intermediate. Similarly, Ca-citrate and Ca-oxalate salts were more insoluble than Ca-acetate and Ca-succinate salts. Regarding aluminium complexation, hydroxyls, sulphates, and acid competition was highlighted. The exploration of acid mixtures showed the preponderant effect of oxalate and citrate over acetate and succinate

Real-time electrochemical LAMP: a rational comparative study of different DNA intercalating and non-intercalating redox probes

International audienceWe present a comparative study of ten redox-active probes for use in real-time electrochemical loop-mediated isothermal amplification (LAMP). Our main objectives were to establish the criteria that need to be fulfilled for minimizing some of the current limitations of the technique and to provide future guidelines in the search for ideal redox reporters. To ensure a reliable comparative study, each redox probe was tested under similar conditions using the same LAMP reaction and the same entirely automatized custom-made real-time electrochemical device (designed for electrochemically monitoring in real-time and in parallel up to 48 LAMP samples). Electrochemical melt curve analyses were recorded immediately at the end of each LAMP reaction. Our results show that there are a number of intercalating and non-intercalating redox compounds suitable for real-time electrochemical LAMP and that the best candidates are those able to intercalate strongly into ds-DNA but not too much to avoid inhibition of the LAMP reaction. The strongest intercalating redox probes were finally shown to provide higher LAMP sensitivity, speed, greater signal amplitude, and cleaner-cut DNA melting curves than the non-intercalating molecules

Behavioural response of green peach aphid Myzus persicae (Sulzer) to volatiles from different rosemary (Rosmarinus officinalis L.) clones

Previous studies have shown that rosemary (Rosmarinus officinalis L.) can serve as a companion plant to control Myzus persicae (Sulzer) because of the repellent effect of certain volatile organic compounds (VOCs) that it emits. In the present study, we investigated which of five clones of rosemary may reveal a repellent effect on M. persicae and aimed to determine the possible VOCs involved.Analyses of the mixtures of VOCs released by the different clones revealed the presence of 15 main components. However, each clone was characterized by a specific volatile profile showing the existence of marked chemical variability.By testing the identified VOCs individually, using a dual‐choice olfactometer, we observed that five volatiles had a significant repulsive effect on M. persicae: bornyl acetate, camphor, α‐terpineol, terpinene‐4‐ol and geranyl acetone. In addition, only one clone of rosemary elicited a significant repulsive action.Nevertheless, all of the tested clones released compounds that are repellent to the aphid when tested individually. Therefore, the emission of individual volatiles by a rosemary plant is not sufficient to elicit a repellent effect.The concentration, proportion and even the association/synergy of VOCs in the released olfactory bouquets can probably explain these contrasting results and are worthy of additional exploration in future studies

Adherence to antiretroviral therapy assessed by drug level monitoring and self-report in cameroon

OBJECTIVES: To compare adherence to antiretroviral therapy using drug level monitoring and self-report and to explore the relation between these 2 methods and viral load measurements. METHODS: Sixty patients received a fixed-dose combination of nevirapine, stavudine, and lamivudine in a clinical study in Cameroon. Adherence was assessed every 6 months until month 36 by nevirapine minimal plasma concentration and self-report. Plasma HIV-1 viral load was determined at the same time. Analyses included 159 complete observations. RESULTS: The proportion of patients labeled as "adherent" was significantly lower using nevirapine monitoring (88.7%, 95% confidence interval [CI]: 82.7 to 93.2) than self-report (97.5%, CI: 93.7 to 99.3; P = 0.002). Virologic failure was associated with the nevirapine concentration (adjusted odds ratio [aOR] = 4.43; P = 0.018) but not with the self-reported adherence (aOR = 0.84; P = 0.9). As compared with the virologic outcome, the sensitivity of nevirapine level monitoring for predicting inadequate adherence was 20.5%, the specificity was 91.7%, the positive predictive value was 44.4%, and the negative predictive value was 78.0%. For self-report, the respective values were 2.6%, 97.5%, 25.0%, and 75.5%. CONCLUSIONS: Drug level monitoring provided a more reliable estimate of adherence than self-report. This method could be used in research settings. Operational research is required to define how to improve the accuracy of the self-report method because it is the most feasible method in clinical practice