Soil nitrogen affects phosphorus recycling: foliar resorption and plant–soil feedbacks in a northern hardwood forest

Previous studies have attempted to link foliar resorption of nitrogen and phosphorus to their respective availabilities in soil, with mixed results. Based on resource optimization theory, we hypothesized that the foliar resorption of one element could be driven by the availability of another element. We tested various measures of soil N and P as predictors of N and P resorption in six tree species in 18 plots across six stands at the Bartlett Experimental Forest, New Hampshire, USA. Phosphorus resorption efficiency (P , 0.01) and proficiency (P ¼ 0.01) increased with soil N content to 30 cm depth, suggesting that trees conserve P based on the availability of soil N. Phosphorus resorption also increased with soil P content, which is difficult to explain based on single-element limitation, but follows from the correlation between soil N and soil P. The expected single-element relationships were evident only in the O horizon: P resorption was high where resin-available P was low in the Oe (P , 0.01 for efficiency, P , 0.001 for proficiency) and N resorption was high where potential N mineralization in the Oa was low (P , 0.01 for efficiency and 0.11 for proficiency). Since leaf litter is a principal source of N and P to the O horizon, low nutrient availability there could be a result rather than a cause of high resorption. The striking effect of soil N content on foliar P resorption is the first evidence of multiple-element control on nutrient resorption to be reported from an unmanipulated ecosystem

Familial aggregation of systemic lupus erythematosus and coaggregation of autoimmune diseases in affected families

IMPORTANCE: Relatives of patients with systemic lupus erythematosus (SLE) appear to be at higher risk of SLE and other autoimmune diseases, but estimates of individual familial risks are largely unavailable or unreliable. Furthermore, relative contributions of genetic, shared, and unshared environmental factors to SLE susceptibility remain unclear. OBJECTIVE: To examine familial aggregation and heritability of SLE and the relative risks (RRs) of other autoimmune diseases in relatives of patients with SLE. DESIGN, SETTING, AND PARTICIPANTS: A population-based family study using the Taiwan National Health Insurance Research Database was conducted. Participants included all individuals (N = 23,658,577) registered with that database in 2010; of these, 18,283 had SLE. We identified 21,009,551 parent-child relationships, 17,168,340 full sibling pairs, and 342,066 twin pairs. Diagnoses of SLE were ascertained from March 1, 1995, to December 31, 2010, and analysis was conducted between March 1 and August 15, 2014. MAIN OUTCOMES AND MEASURES: The prevalence and RRs of SLE and other autoimmune diseases in relatives and spouses of patients with SLE as well as the relative contributions of heritability, shared, and nonshared environmental factors to SLE susceptibility. RESULTS: Among the more than 23 million participants, the RRs (95% CIs) for SLE were 315.94 (210.66-473.82) for twins of the patients, 23.68 (20.13-27.84) for siblings, 11.44 (9.74-13.43) for parents, 14.42 (12.45-16.70) for offspring, and 4.44 (2.38-8.30) for spouses without genetic similarity. The accountability for phenotypic variance of SLE was 43.9% for heritability, 25.8% for shared environmental factors, and 30.3% for nonshared environmental factors. The RRs (95% CIs) in individuals with a first-degree relative with SLE were 5.87 (4.89-7.05) for primary Sjogren syndrome, 5.40 (3.37-8.65) for systemic sclerosis, 2.95 (2.04-4.26) for myasthenia gravis, 2.77 (1.45-5.32) for idiopathic inflammatory myositis, 2.66 (2.28-3.11) for rheumatoid arthritis, 2.58 (1.16-5.72) for multiple sclerosis, 1.68 (1.22-2.32) for type 1 diabetes mellitus, 1.39 (0.66-2.91) for inflammatory bowel diseases, and 0.86 (0.43-1.71) for vasculitis. CONCLUSIONS AND RELEVANCE: The individual risks of SLE and other autoimmune diseases were increased in families that included patients with SLE. The heritability of SLE was estimated to be 43.9%. These data should be considered when counseling families with affected members

Familial risk of Sjögren's syndrome and co-aggregation of autoimmune diseases in affected families: a nationwide population study

Objective: To investigate familial aggregation of Sjögren's syndrome (SS) and the relative risks (RRs) of other autoimmune disease in relatives of patients with SS. Methods: We identified 23,658,577 beneficiaries enrolled in the Taiwan National Health Insurance system in 2010, of whom 12,754 had SS. We identified 21,009,551 parent–child relationships and 17,168,340 pairs of full siblings. The familial risks of SS and other autoimmune diseases, tetrachoric correlation, and familial transmission were estimated. Results: We identified 105 patients with SS who had an affected first-degree relative. The RR of SS was 18.99 (95% confidence interval [95% CI] 9.76–36.93) in siblings of patients with SS, 11.31 (95% CI 8.34–15.33) in offspring, and 12.46 (95% CI 9.34–16.62) in parents. Tetrachoric correlation coefficients were 0.53 (95% CI 0.41–0.65) for cotwins of affected individuals and 0.21 (95% CI 0.16–0.26) for full siblings. The familial transmission (heritability plus shared environmental contribution) was 0.54 (95% CI 0.44–0.77). In first-degree relatives of patients with SS, the RRs were 2.95 (95% CI 2.33–3.73) for rheumatoid arthritis, 6.25 (95% CI 5.15–7.58) for systemic lupus erythematosus, 2.39 (95% CI 0.77–7.41) for systemic sclerosis, 0.71 (95% CI 0.10–5.07) for idiopathic inflammatory myopathy, 1.97 (95% CI 1.29–3.02) for type 1 diabetes mellitus, 3.38 (95% CI 1.26–9.05) for multiple sclerosis, 1.67 (95% CI 0.83–3.33) for myasthenia gravis, 1.25 (95% CI 1.04–1.50) for psoriasis, 1.21 (95% CI 0.39–3.76) for inflammatory bowel disease, and 2.29 (95% CI 1.19–4.40) for vasculitis. Conclusion: The risk of SS and other autoimmune diseases is increased in relatives of patients with SS, and more than one-half of phenotypic variance in SS can be explained by familial factors

Epidemiology and management of gout in Taiwan: a nationwide population study

INTRODUCTION: Gout is the most common inflammatory arthritis worldwide and is the only type of chronic arthritis that potentially can be ‘cured’. However, data on gout incidence, prevalence and management, assessed at multiple time points in the same population, are sparse, particularly in Asian populations. The aim of this study was to describe trends in the epidemiology of gout in the general population of Taiwan. METHODS: The National Health Insurance Research Database was used to identify patients with gout and to estimate the prevalence and incidence of gout for each calendar year from 2005 to 2010. The pattern of gout management was also examined. RESULTS: Of 23,371,362 beneficiaries in 2010, there were 1,458,569 prevalent and 56,595 incident cases of gout, giving a prevalence of 6.24% (95% confidence interval (CI), 6.23% to 6.25%) and an incidence of 2.74 (95% CI, 2.72 to 2.76) per 1,000 person-years. The annual percentage change (APC) of the standardised prevalence was −0.7% (95% CI, −1.7% to 0.3%; P = 0.14), suggesting that the prevalence of gout was essentially the same throughout the study period. However, The APC of incidence was −13.4 (95% CI, −16.1 to −10.6) between 2005 and 2007 and −2.1 (95% CI, −10.4 to 7.1) between 2007 and 2010. Regions with the highest prevalence and incidence were eastern coastal counties and offshore islets, where indigenous people are clustered. Among prevalent gout cases in 2010, only 22.93% (95% CI, 22.87% to 23.00%) were prescribed urate-lowering treatment (ULT), which remained unchanged between 2005 and 2010 at an APC of 0.0 (95% CI, −3.8 to 4.0). Uricosuric agents were more commonly prescribed than xanthine oxidase inhibitors in Taiwan. CONCLUSIONS: In Taiwan, 1 in 16 people have gout. Whereas the incidence has decreased recently, the prevalence remains unchanged. Management of gout in Taiwan is poor, with only one in five affected people being treated with ULT

No Dynamics in the Extremal Kerr Throat

Motivated by the Kerr/CFT conjecture, we explore solutions of vacuum general relativity whose asymptotic behavior agrees with that of the extremal Kerr throat, sometimes called the Near-Horizon Extreme Kerr (NHEK) geometry. We argue that all such solutions are diffeomorphic to the NHEK geometry itself. The logic proceeds in two steps. We first argue that certain charges must vanish at all times for any solution with NHEK asymptotics. We then analyze these charges in detail for linearized solutions. Though one can choose the relevant charges to vanish at any initial time, these charges are not conserved. As a result, requiring the charges to vanish at all times is a much stronger condition. We argue that all solutions satisfying this condition are diffeomorphic to the NHEK metric.Comment: 42 pages, 3 figures. v3: minor clarifications and correction

Development of Homo- and Heteromultimetallic Complexes Supported by 1,8- Naphthyridine Ligands

Chapter 1. Multimetallic moieties are widely invoked as the active sites of enzymes and heterogeneous materials responsible for the facilitation of chemical transformations that, to date, are very challenging to achieve in research laboratories or industrial settings under mild conditions. Attention in the field has largely been focused on the investigation of these difficult-to-study systems by developing relatively simpler molecular analogues. The close coordination of multiple metal centers is thought to allow for the hypothesized metal-metal cooperativity by enabling multielectron processes through electronic interactions and coordinating/activating substrates. Systems have been designed to exploit cooperativity between transition-metal pairs, which can lead to unusual reactivity or selectivity. This chapter briefly summarizes historical and contemporary achievements in this area of research with special attention focused on the utilization of the 1,8-naphthyridine motif.Chapter 2. A dinucleating 1,8-naphthyridine ligand featuring fluorene-9,9-diyl-linked phosphinoside arms (PNNPFlu) was synthesized and used to obtain the cationic dicopper complexes: 2.2, [(PNNPFlu)Cu₂(μ‐Ph)][NTf₂]; 2.6, [(PNNPFlu)Cu₂(μ‐CCPh)][NTf₂]; 2.3, [(PNNPFlu)Cu₂(μ‐OtBu)][NTf₂]. Complex 2.3 reacted with diboranes to afford dicopper μ‐boryl species (2.4, with μ‐Bcat; cat = catecholate and 2.5, with μ‐Bpin; pin = pinacolate) that are more reactive in C(sp)–H bond activations and toward activations of CO₂ and CS₂, compared to dicopper μ‐boryl complexes supported by a 1,8-naphthyridine-based ligand with di(pyridyl) side arms. The solid-state structures and DFT analysis indicate that the higher reactivity of 2.4 and 2.5 relates to changes in the coordination sphere of copper, rather than to perturbations on the Cu–B bonding interactions. Addition of xylyl isocyanide (CNXyl) to 2.4 gave 2.7, [(PNNPFlu)Cu₂(μ‐Bcat)(CNXyl)][NTf₂], demonstrating that the lower coordination number at copper is chemically significant. Reactions of 2.4 and 2.5 with CO₂ yielded the corresponding dicopper borate complexes: 2.8, [(PNNPFlu)Cu₂(μ‐OBcat)][NTf₂]; 2.9, [(PNNPFlu)Cu₂(μ‐OBpin)][NTf₂]. Complex 2.4 demonstrated catalytic reduction in the presence of excess diborane. Related reactions of 2.4 and 2.5 with CS₂ provided the insertion products: 2.10, [(PNNPFlu)Cu₂]₂[μ‐S₂C(Bcat)₂][NTf₂]₂; 2.11, [(PNNPFlu)Cu₂(μ,κ²‐S₂CBpin)][NTf₂], respectively. These products feature Cu–S–C–B linkages analogous to those of proposed CO₂ insertion intermediates.Chapter 3. The selective synthesis and isolation of homo- and heterobimetallic Fe/Mn complexes was facilitated by the synthesis of a new symmetrical 1,8-naphthyridine ligand featuring bioinspired triazole side arms (MTN). This ligand was used to obtain the cationic diiron complex: 3.4, [(MTN)₂Fe₂(μ-Cl)(THF)₂][NTf₂]₃, and monometallic iron complex: 3.5, MTN·FeCl₂. The vacant coordination position in 3.5 was used as a starting point for the coordination of an additional metal center. The addition of one equivalent of Mn[OTf]₂(MeCN)₃ and Fe[OTf]₂ to 3.5 filled the vacant coordination position to yield: 3.6, [(MTN)₃Fe(μ-Cl)₂Mn][OTf₂]₂, 3.7, [(MTN)₃Fe₂(μ-Cl)₂][OTf₂]₂. The identity and characterization of 3.4, 3.5, and 3.7 are supported by mass spectrometry, X-ray diffraction analysis, and EPR spectroscopy. Furthermore, the identity of the metal center (3.6), and the ligand field environment (3.4), can both lead to varied magnetic behavior compared to the prototypical example of 3.7, likely originating from the particular exchange pathway of these materials, as investigated by variable-temperature magnetic susceptibility measurements.Chapter 4. Reaction of a dicopper(I) acetonitrile complex resulted in the activation of elemental sulfur to yield a formally 2Cu¹:2Cu² tetracopper mixed-valent μ-disulfide complex (4.1). Furthermore, stoichiometric reducing (cobaltocene) or oxidizing (Ag[NTf₂]) agents allow for the reversible interconversion between complex 4.1, a formally 3Cu¹:Cu² species (4.2), and a 4Cu¹ species (4.3). Given the isostructural nature of these complexes, the electronic communication between the metal centers of 4.1, 4.2, and 4.3 were spectroscopically investigated with UV-Vis and EPR techniques, revealing the relative delocalization of the electron holes on all four copper centers of the complexes in 4.1 and 4.2. Variable magnetometry of 4.1, 4.2, and 4.3 also reveals antiferromagnetic, ferromagnetic, and temperature-independent paramagnetic interactions, respectively. This study provides insight into related biological mixed-valent multicopper systems, shedding light on the unique electronic exchange interactions between the metal atoms.Chapter 5. A novel scaffold, 2,7-bis(2-fluorophenyl)-1,8-naphthyridine (5.1), was synthesized via Suzuki cross-coupling methods, allowing for facile access to new potential binucleating ligands. A variety of donor atoms can be furnished utilizing a straightforward nucleophilic aromatic substitution reaction. This versatility was demonstrated in the synthesis of two new ligands that feature S- and P-atom donors from sodium thiophenolate and potassium diphenylphosphide to yield an SNNS (5.2) and PNNP (5.3) extended pincer ligand, respectively. However, preliminary metalation conditions with 2.0 equiv. [Cu(NCMe)₄][NTf₂] suggest the coordination of only one copper center, as confirmed by multinuclear NMR spectroscopy and mass spectrometry analysis. However, this work provides a proof-of-concept for a versatile stepwise synthetic strategy for new 1,8-naphthyridine-based ligands whose bimetallic binding capabilities may be supported by expanding the scope of the metalation conditions.Chapter 6. The synthetic platforms and techniques developed in Chapters 2–5 and the insights garnered therein provided countless opportunities to further develop the homo- and heterobimetallic capabilities of dinucleating 1,8-naphthyridine-based ligands. This chapter presents the development of a new robust unsymmetrical 1,8-naphthyridine-based ligand, three preliminary heterobimetallic (Cu/Zn, Ni/Fe, and Cu/Mo) results, and one preliminary homobimetallic (Co/Co) result with relevance to CO₂ reduction systems and Pauson-Khand catalysis, respectively. Since these stories are works in progress, only a few highlights are presented

Including Gene Edited Sires in Genetic Evaluations

A simulation study investigated and provided potential solutions to practical issues that could arise from including gene-edited sires in routine genetic evaluations. Gene-editing is a technique for adding, deleting, or replacing nucleotides in the genome. Editing nucleotides controlling important socioeconomic traits (e.g., growth, carcass, disease susceptibility) is expected to improve rates of genetic gain. However, targeted alterations of the genome can affect the relationship among individuals and, consequently, introduce bias in Expected Progeny Differences. The current study illustrated that, indeed, Expected Progeny Differences for the progeny of edited sires were underestimated. Consequently, these animals would be less likely to be selected as parents for subsequent generations. Therefore, if edited sires are introduced into genetic evaluations, the statistical models used in the evaluation need to appropriately accommodate the changes among animals that the targeted gene edits create, and adjusting the kinship among animals is one way to do this. Without accounting for these targeted changes Expected Progeny Differences will be biased, and selection decisions could be made incorrectly

Status of Axisymmetric CFD of an Eleven Inch Diameter Hybrid Rocket Motor

Current status of a steady state, axisymmetric analysis of an experimental 11 inch diameter hybrid rocket motor internal flow field is given. The objective of this effort is to develop a steady state axisymmetric model of the 11 inch hybrid rocket motor which can be used as a design and/or analytical tool. A test hardware description, modeling approach, and future plans are given. The analysis was performed with FDNS implementing several finite rate chemistry sets. A converged solution for a two equation and five species set on a 'fine' grid is shown

Writing in Britain and Ireland, c. 400 to c. 800

No abstract available