Long-term carbon and nitrogen dynamics at SPRUCE revealed through stable isotopes in peat profiles

Peatlands encode information about past vegetation dynamics, climate, and microbial processes. Here, we used δ15N and δ13C patterns from 16 peat profiles to deduce how the biogeochemistry of the Marcell S1 forested bog in northern Minnesota responded to environmental and vegetation change over the past  ∼ 10000 years. In multiple regression analyses, δ15N and δ13C correlated strongly with depth, plot location, C∕N, %N, and each other. Correlations with %N, %C, C∕N, and the other isotope accounted for 80% of variance for δ15N and 38% of variance for δ13C, reflecting N and C losses. In contrast, correlations with depth and topography (hummock or hollow) reflected peatland successional history and climate. Higher δ15N in plots closer to uplands may reflect upland-derived DON inputs and accompanying shifts in N dynamics in the lagg drainage area surrounding the bog. The Suess effect (declining δ13CO2 since the Industrial Revolution) lowered δ13C in recent surficial samples. High δ15N from −35 to −55cm probably indicated the depth of ectomycorrhizal activity after tree colonization of the peatland over the last 400 years, as confirmed by the occasional presence of wood down to −35cm depth. High δ13C at  ∼ 4000 years BP (−65 to −105cm) could reflect a transition at that time to slower rates of peat accumulation, when 13C discrimination during peat decomposition may increase in importance. Low δ13C and high δ15N at −213 and −225cm ( ∼ 8500 years BP) corresponded to a warm period during a sedge-dominated rich fen stage. The above processes appear to be the primary drivers of the observed isotopic patterns, whereas there was no clear evidence for methane dynamics influencing δ13C patterns

Management of patients presenting with diarrhoea to a regional emergency department in KwaZulu-Natal: Call for clearer, more relevant guidance

Background. HIV is prevalent throughout South Africa, and diarrhoea is a common presentation to the emergency department (ED) among both HIV-infected and -uninfected individuals. Method. We audited the management of diarrhoea against standard guidelines in the ED of a regional hospital in KwaZulu-Natal. Patients presenting with diarrhoea as their chief complaint were eligible and data were collected prospectively. Results. A total of 72 patients were included: 58 (81%) of patients were HIV-positive with an average CD4+ count of 180 cells/ μl. A total of 34 stool samples were sent for standard microscopy and culture (M&C), among which 26 were positive (76%). Forty-three patients (60%) received antibiotics, 15 of whom had positive stool M&C. In all cases, the final diagnosis was listed as acute gastroenteritis without further specification, and antibiotic use according to guidelines appeared inconsistent. Conclusion. Based on this audit, we suggest that current guidelines are not clear concerning management of acute diarrhoea in HIVinfected individuals, and that the lack of clear management strategies is likely to affect patient safety and increase antibiotic resistance

Radar-aeolian roughness project

The objective is to establish an empirical relationship between measurements of radar, aeolian, and surface roughness on a variety of natural surfaces and to understand the underlying physical causes. This relationship will form the basis for developing a predictive equation to derive aeolian roughness from radar backscatter. Results are given from investigations carried out in 1989 on the principal elements of the project, with separate sections on field studies, radar data analysis, laboratory simulations, and development of theory for planetary applications

Embeddings of SL(2,Z) into the Cremona group

Geometric and dynamic properties of embeddings of SL(2,Z) into the Cremona group are studied. Infinitely many non-conjugate embeddings which preserve the type (i.e. which send elliptic, parabolic and hyperbolic elements onto elements of the same type) are provided. The existence of infinitely many non-conjugate elliptic, parabolic and hyperbolic embeddings is also shown. In particular, a group G of automorphisms of a smooth surface S obtained by blowing-up 10 points of the complex projective plane is given. The group G is isomorphic to SL(2,Z), preserves an elliptic curve and all its elements of infinite order are hyperbolic.Comment: to appear in Transformation Group

Effects of Noise Reduction and Care Clustering on Quality of Sleep in Critical Care Patients

Introduction: Sleep deprivation has detrimental effects on critical patients’ health. A lack of sleep can affect multiple body systems. There are nursing interventions that can reduce sleep deprivation. However, there is inconclusive evidence on how to properly assess sleep deprivation and implement sleep promoting nursing interventions in clinical practice. Purpose: The purpose of this literature review is to examine the effects of noise reduction and nursing care clustering on improving the quality of patient sleep in the critical care setting. Methods: This literature review was conducted using 10 sources published within the last 5 years. Inclusion criteria consisted of articles about the effects of noise, quality of sleep, and implementation of nurse care clustering on various critical care populations. The 6 databases used for this research were UpToDate, CINAHL, PubMed, PsycInfo, Proquest, and CCForum. This research concentrated on examining articles containing nursing interventions for noise reduction and care clustering related to quality of sleep. Results: Noise has a negative effect on sleep by causing more arousals/awakenings, which greatly impacts the restorative function of the process. Noise is not the only sleep disturbing factor, but it has been shown to be significant. Some noise sources cannot be eliminated due to safety reasons, but interventions exist to help counteract the effects of noise. Nursing care interventions are as disruptive to sleep as noise. 13.9% of nursing interruptions could be safely omitted, and nurses should cluster care to promote sleep. Interventions to prevent sleep disruption can be practical in routine nursing, but nurses are less likely to implement them at night because prioritizing care clustering can require more time and effort. Discussion: Sleep deprivation causes major health concerns in critical care patients. Noise and nursing care interventions have been found to cause equal disruptions in sleep. Noise reduction and care clustering have been observed to reduce sleep deprivation. Further evidence is needed on how to effectively and practically implement these nursing interventions into daily nursing practice

Probing the isovector transition strength of the low-lying nuclear excitations induced by inverse kinematics proton scattering

A compact approach based on the folding model is suggested for the determination of the isoscalar and isovector transition strengths of the low-lying ($\Delta S=\Delta T=0$) excitations induced by inelastic proton scattering measured with exotic beams. Our analysis of the recently measured inelastic $^{18,20}$O+p scattering data at $E_{\rm lab}=30$ and 43 MeV/nucleon has given for the first time an accurate estimate of the isoscalar $\beta_0$ and isovector $\beta_1$ deformation parameters (which cannot be determined from the (p,p') data alone by standard methods) for 2$^+_1$ and $3^-_1$ excited states in $^{18,20}$O. Quite strong isovector mixing was found in the 2$^+_1$ inelastic $^{20}$O+p scattering channel, where the strength of the isovector form factor $F_1$ (prototype of the Lane potential) corresponds to a $\beta_1$ value almost 3 times larger than $\beta_0$ and a ratio of nuclear transition matrix elements $M_n/M_p\simeq 4.2$.Comment: 5 pages, 3 figure

A Policy Impact Evaluation Model For Scotland: Decoupling Single Farm Payments

The purpose of this paper is to assess the impacts of decoupling single farm payments in Scotland. It focuses on aggregate impacts on the agricultural products in domestic and external markets and the spill-over effect of this on the non-agricultural sector as well as an aggregate impact on the Scottish GDP. In order to capture system-wide impacts of the policy reform, a CGE model was formulated and implemented using a social accounting matrix constructed for Scotland. The simulation results suggest that the Scottish agricultural sector may encounter declines in output and factor us as a result of the policy reform. However, this critically depends on two factors: (a) the price effect of the policy reform on Scottish agricultural products relative to the EU average as well as the conditions of changes in world agricultural market prices; and (b) the extent to which customers would be sensitive to price effects of the policy reform. As far as the spill-over effect to the non-agricultural sector is concerned, decoupling of direct payments seems to have a positive spill-over effect. Similarly, the aggregate GDP effect is positive under all simulation scenarios. Critically, the simulation experiments indicate that policy shock may have a symmetrical outcome across the two sectors, with contractions in agriculture being accompanied by expansions in the non-agricultural sector, mainly because of factor market interactions between the two sectors.