bluuebunny/crossref_metadata_2025 huggingface dataset:
Linking temperature sensitivity of soil CO2 release to substrate, environmental, and microbial properties across alpine ecosystems
Authors: Ding Jinzhi , Chen Leiyi , Zhang Beibei , Liu Li , Yang Guibiao , Fang Kai , Chen Yongliang , Li Fei , Kou Dan , Ji Chengjun , Luo Yiqi , Yang Yuanhe
Published: August 2016

Our knowledge of fundamental drivers of the temperature sensitivity (Q10) of soil carbon dioxide (CO2) release is crucial for improving the predictability of soil carbon dynamics in Earth System Models. However, patterns and determinants of Q10 over a broad geographic scale are not fully understood, especially in alpine ecosystems. Here we addressed this issue by incubating surface soils (0–10 cm) obtained from 156 sites across Tibetan alpine grasslands. Q10 was estimated from the dynamics of the soil CO2 release rate under varying temperatures of 5–25°C. Structure equation modeling was performed to evaluate the relative importance of substrate, environmental, and microbial properties in regulating the soil CO2 release rate and Q10. Our results indicated that steppe soils had significantly lower CO2 release rates but higher Q10 than meadow soils. The combination of substrate properties and environmental variables could predict 52% of the variation in soil CO2 release rate across all grassland sites and explained 37% and 58% of the variation in Q10 across the steppe and meadow sites, respectively. Of these, precipitation was the best predictor of soil CO2 release rate. Basal microbial respiration rate (B) was the most important predictor of Q10 in steppe soils, whereas soil pH outweighed B as the major regulator in meadow soils. These results demonstrate that carbon quality and environmental variables coregulate Q10 across alpine ecosystems, implying that modelers can rely on the “carbon‐quality temperature” hypothesis for estimating apparent temperature sensitivities, but relevant environmental factors, especially soil pH, should be considered in higher‐productivity alpine regions.
The effectiveness and resilience of phosphorus management practices in the Lake Simcoe watershed, Ontario, Canada
Authors: Crossman J. , Futter M. N. , Palmer M. , Whitehead P. G. , Baulch H. M. , Woods D. , Jin L. , Oni S. K. , Dillon P. J.
Published: August 2016

Uncertainty surrounding future climate makes it difficult to have confidence that current nutrient management strategies will remain effective. This study used monitoring and modeling to assess current effectiveness (% phosphorus reduction) and resilience (defined as continued effectiveness under a changing climate) of best management practices (BMPs) within five catchments of the Lake Simcoe watershed, Ontario. The Integrated Catchment Phosphorus model (INCA‐P) was used, and monitoring data were used to calibrate and validate a series of management scenarios. To assess current BMP effectiveness, models were run over a baseline period 1985–2014 with and without management scenarios. Climate simulations were run (2070–2099), and BMP resilience was calculated as the percent change in effectiveness between the baseline and future period. Results demonstrated that livestock removal from water courses was the most effective BMP, while manure storage adjustments were the least. Effectiveness varied between catchments, influenced by the dominant hydrological and nutrient transport pathways. Resilience of individual BMPs was associated with catchment sensitivity to climate change. BMPs were most resilient in catchments with high soil water storage capacity and small projected changes in frozen‐water availability and in soil moisture deficits. Conversely, BMPs were less resilient in catchments with larger changes in spring melt magnitude and in overland flow proportions. Results indicated that BMPs implemented are not always those most suited to catchment flow pathways, and a more site‐specific approach would enhance prospects for maintaining P reduction targets. Furthermore, BMP resilience to climate change can be predicted from catchment physical properties and present‐day hydrochemical sensitivity to climate forcing.
Climate forcing for dynamics of dissolved inorganic nutrients at Palmer Station, Antarctica: An interdecadal (1993–2013) analysis
Authors: Kim Hyewon , Doney Scott C. , Iannuzzi Richard A. , Meredith Michael P. , Martinson Douglas G. , Ducklow Hugh W.
Published: August 2016

We analyzed 20 years (1993–2013) of observations of dissolved inorganic macronutrients (nitrate, N; phosphate, P; and silicate, Si) and chlorophyll a (Chl) at Palmer Station, Antarctica (64.8°S, 64.1°W) to elucidate how large‐scale climate and local physical forcing affect the interannual variability in the seasonal phytoplankton bloom and associated drawdown of nutrients. The leading modes of nutrients (N, P, and Si empirical orthogonal functions 1, EOF1) represent overall negative anomalies throughout growing seasons, showing a mixed signal of variability in the initial levels and drawdown thereafter (low‐frequency dynamics). The second most common seasonal patterns of nitrate and phosphate (N and P EOF2) capture prolonged drawdown events during December–March, which are correlated to Chl EOF1. Si EOF2 captures a drawdown event during November–December, which is correlated to Chl EOF2. These different drawdown patterns are shaped by different sets of physical and climate forcing mechanisms. N and P drawdown events during December–March are influenced by the winter and spring Southern Annular Mode (SAM) phase, where nutrient utilization is enhanced in a stabilized upper water column as a consequence of SAM‐driven winter sea ice and spring wind dynamics. Si drawdown during November–December is influenced by early sea ice retreat, where ice breakup may induce abrupt water column stratification and a subsequent diatom bloom or release of diatom cells from within the sea ice. Our findings underscore that seasonal nutrient dynamics in the coastal WAP are coupled to large‐scale climate forcing and related physics, understanding of which may enable improved projections of biogeochemical responses to climate change.
A structural equation model analysis of phosphorus transformations in global unfertilized and uncultivated soils
Authors: Hou Enqing , Chen Chengrong , Kuang Yuanwen , Zhang Yuguang , Heenan Marijke , Wen Dazhi
Published: August 2016

Understanding the soil phosphorus (P) cycle is a prerequisite for predicting how environmental changes may influence the dynamics and availability of P in soil. We compiled a database of P fractions sequentially extracted by the Hedley procedure and its modification in 626 unfertilized and uncultivated soils worldwide. With this database, we applied structural equation modeling to test hypothetical soil P transformation models and to quantify the importance of different soil P pools and P transformation pathways in shaping soil P availability at a global scale. Our models revealed that soluble inorganic P (Pi, a readily available P pool) was positively and directly influenced by labile Pi, labile organic P (Po), and primary mineral P and negatively and directly influenced by secondary mineral P; soluble Pi was not directly influenced by moderately labile Po or occluded P. The overall effect on soluble Pi was greatest for labile Pi followed by the organic P pools, occluded P, and then primary mineral P; the overall influence from secondary mineral P was small. Labile Pi was directly linked to all other soil P pools and was more strongly linked than soluble Pi to labile Po and primary mineral P. Our study highlights the important roles of labile Pi in mediating P transformations and in determining overall P availability in soils throughout the world.
Altitudinal dependence of meteor radio afterglows measured via optical counterparts
Authors: Obenberger K. S. , Holmes J. M. , Dowell J. D. , Schinzel F. K. , Stovall K. , Sutton E. K. , Taylor G. B.
Published: August 2016

Utilizing the all‐sky imaging capabilities of the first station of the Long Wavelength Array along with a host of all‐sky optical cameras, we have now observed 44 optical meteor counterparts to radio afterglows. Combining these observations, we have determined the geographic positions of all 44 afterglows. Comparing the number of radio detections as a function of altitude above sea level to the number of expected bright meteors, we find a strong altitudinal dependence characterized by a cutoff below ∼90 km, below which no radio emission occurs, despite the fact that many of the observed optical meteors penetrated well below this altitude. This cutoff suggests that wave damping from electron collisions is an important factor for the evolution of radio afterglows. This finding agrees with the hypothesis that the emission is the result of electron plasma wave emission.
Proxy representation of Arctic ocean bottom pressure variability: Bridging gaps in GRACE observations
Authors: Peralta‐Ferriz Cecilia , Morison James H. , Wallace John M.
Published: August 2016

Using time‐varying ocean bottom pressure (OBP) from the Gravity Recovery and Climate Experiment (GRACE), a 9 year in situ OBP record at the North Pole, and wind reanalysis products, we perform a linear regression analysis to identify primary predictor time series that enable us to create a proxy representation of the Arctic time‐varying OBP that explains the largest fraction of the observed Arctic OBP variability. After cross validation, two predictors—North Pole OBP record and wind‐OBP coupling from maximum covariance analysis—explain 50% of the total variance of the Arctic OBP. This work provides a means for bridging existing short gaps in GRACE measurements and potentially longer future gaps that may result if GRACE and its follow‐on mission do not overlap. The technique may be applicable to bridge gaps in GRACE measurements in other oceanic regions.
Deep nightside photoelectron observations by MAVEN SWEA: Implications for Martian northern hemispheric magnetic topology and nightside ionosphere source
Authors: Xu Shaosui , Mitchell David , Liemohn Michael , Dong Chuanfei , Bougher Stephen , Fillingim Matthew , Lillis Robert , McFadden James , Mazelle Christian , Connerney Jack , Jakosky Bruce
Published: August 2016

The Mars Atmosphere and Volatile EvolutioN (MAVEN) mission samples the Mars ionosphere down to altitudes of ∼150 km over a wide range of local times and solar zenith angles. On 5 January 2015 (Orbit 520) when the spacecraft was in darkness at high northern latitudes (solar zenith angle, SZA >120°; latitude >60°), the Solar Wind Electron Analyzer (SWEA) instrument observed photoelectrons at altitudes below 200 km. Such observations imply the presence of closed crustal magnetic field loops that cross the terminator and extend thousands of kilometers to the deep nightside. This occurs over the weak northern crustal magnetic source regions, where the magnetic field has been thought to be dominated by draped interplanetary magnetic fields (IMF). Such a day‐night magnetic connectivity also provides a source of plasma and energy to the deep nightside. Simulations with the SuperThermal Electron Transport (STET) model show that photoelectron fluxes measured by SWEA precipitating onto the nightside atmosphere provide a source of ionization that can account for the
density measured by the Suprathermal and Thermal Ion Composition (STATIC) instrument below 200 km. This finding indicates another channel for Martian energy redistribution to the deep nightside and consequently localized ionosphere patches and potentially aurora.
The Tiny Ionospheric Photometer (TIP) on the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC/FORMOSAT‐3)
Authors: Dymond K. F. , Budzen S. A. , Coker C. , Chua D. H.
Published: August 2016

The Tiny Ionospheric Photometer (TIP) is an ultraviolet nadir‐viewing photometer that flew aboard the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC, also known as FORMOSAT‐3), which was launched on 14 April 2006. One TIP flew on each of the six COSMIC/FORMOSAT3 satellites; these compact instruments operated exclusively at nighttime and observed the O I 135.6 nm emission that is a signature of the decay of the F region ionosphere and, as such, is a diagnostic of the ionospheric state. We describe the TIP instruments and their on‐orbit operation. Additionally, some key science highlights of the mission are presented and discussed.
Dynamic responses of the Earth's radiation belts during periods of solar wind dynamic pressure pulse based on normalized superposed epoch analysis
Authors: Ni Binbin , Xiang Zheng , Gu Xudong , Shprits Yuri Y. , Zhou Chen , Zhao Zhengyu , Zhang Xianguo , Zuo Pingbing
Published: August 2016

Using the electron flux measurements obtained from five satellites (GOES 15 and POES 15, 16, 18, and 19), we investigate the flux variations of radiation belt electrons during forty solar wind dynamic pressure pulses identified between September 2012 and December 2014. By utilizing the mean duration of the pressure pulses as the epoch timeline and stretching or compressing the time phases of individual events to normalize the duration by means of linear interpolation, we have performed normalized superposed epoch analysis to evaluate the dynamic responses of radiation belt energetic electrons corresponding to various groups of solar wind and magnetospheric conditions in association with solar wind dynamic pressure pulses. Our results indicate that by adopting the timeline normalization we can reproduce the typical response of the electron radiation belts to pressure pulses. Radiation belt electron fluxes exhibit large depletions right after the Pdyn peak during the periods of northward interplanetary magnetic field (IMF) Bz and are more likely to occur during the Pdyn pulse under southward IMF Bz conditions. For the pulse events with large negative values of (Dst)min, radiation belt electrons respond in a manner similar to those with southward IMF Bz, and the corresponding postpulse recovery can extend to L ~ 3 and exceed the prepulse flux levels. Triggered by the solar wind pressure enhancements, deeper earthward magnetopause erosion provides favorable conditions for the prompt electron flux dropouts that extend down to L ~ 5, and the pressure pulses with longer duration tend to produce quicker and stronger electron flux decay. In addition, the events with high electron fluxes before the Pdyn pulse tend to experience more severe electron flux dropouts during the course of the pulse, while the largest rate of electron flux increase before and after the pulse occurs under the preconditioned low electron fluxes. These new results help us understand how electron fluxes respond to solar wind dynamic pressure pulses and how these responses depend on the solar wind and geomagnetic conditions and on the preconditions in the electron radiation belts.
Where do ocean microseisms come from? A study of Love‐to‐Rayleigh wave ratios
Authors: Juretzek C. , Hadziioannou C.
Published: August 2016

Our knowledge of the origin of Love waves in the ambient seismic noise is extremely limited. This applies in particular to constraints on source locations and source mechanisms for Love waves in the secondary microseism. Here three‐component beamforming is used to distinguish between the differently polarized wave types in the primary and secondary microseismic noise fields, recorded at several arrays across Europe. We compare characteristics of Love and Rayleigh wave noise, such as source directions and frequency content, measure Love to Rayleigh wave ratios for different back azimuths, and look at the seasonal behavior of our measurements by using a full year of data in 2013. The beamforming results confirm previous observations that back azimuths for Rayleigh and Love waves in both microseismic bands mainly coincide. However, we observe differences in relative directional noise strength between both wave types for the primary microseism. At those frequencies, Love waves dominate on average, with kinetic Love‐to‐Rayleigh energy ratios ranging from 0.6 to 2.0. In the secondary microseism, the ratios are lower, between 0.4 and 1.2. The wave type ratio is directionally homogeneous, except for locations far from the coast. In the primary microseism, our results support the existence of different generation mechanisms. The contribution of a shear traction‐type source mechanism is likely.
Isolating active orogenic wedge deformation in the southern Subandes of Bolivia
Authors: Weiss Jonathan R. , Brooks Benjamin A. , Foster James H. , Bevis Michael , Echalar Arturo , Caccamise Dana , Heck Jacob , Kendrick Eric , Ahlgren Kevin , Raleigh David , Smalley Robert , Vergani Gustavo
Published: August 2016

A new GPS‐derived surface velocity field for the central Andean backarc permits an assessment of orogenic wedge deformation across the southern Subandes of Bolivia, where recent studies suggest that great earthquakes (>Mw 8) are possible. We find that the backarc is not isolated from the main plate boundary seismic cycle. Rather, signals from subduction zone earthquakes contaminate the velocity field at distances greater than 800 km from the Chile trench. Two new wedge‐crossing velocity profiles, corrected for seasonal and earthquake affects, reveal distinct regions that reflect (1) locking of the main plate boundary across the high Andes, (2) the location of and loading rate at the back of orogenic wedge, and (3) an east flank velocity gradient indicative of décollement locking beneath the Subandes. Modeling of the Subandean portions of the profiles indicates along‐strike variations in the décollement locked width (WL) and wedge loading rate; the northern wedge décollement has a WL of ~100 km while accumulating slip at a rate of ~14 mm/yr, whereas the southern wedge has a WL of ~61 km and a slip rate of ~7 mm/yr. When compared to Quaternary estimates of geologic shortening and evidence for Holocene internal wedge deformation, the new GPS‐derived wedge loading rates may indicate that the southern wedge is experiencing a phase of thickening via reactivation of preexisting internal structures. In contrast, we suspect that the northern wedge is undergoing an accretion or widening phase primarily via slip on relatively young thrust‐front faults.
Investigating the stratigraphy of Mare Imbrium flow emplacement with Earth‐based radar
Authors: Morgan G. A. , Campbell B. A. , Campbell D. B. , Hawke B. R.
Published: August 2016

The lunar maria are the product of extensive basaltic volcanism that flooded widespread portions of the Moon's surface. Constraining mare volcanic history therefore provides a window into the endogenic processes responsible for shaping the Moon. Due to the low magma viscosity and the associated thin nature of lava units, the majority of mare surface structures are masked and subdued by impact regolith. Subtle individual mare flow morphologies, coupled with spatial limitations in the use of crater size distributions to distinguish surface units close in age, restrict our understanding of mare stratigraphy. Earth‐based 70 cm wavelength (P band) radar can reveal features beneath the regolith and highlight very subtle changes in the ilmenite content of the flows, providing a unique means to map mare units. Here we map volcanic units in Mare Imbrium using high‐resolution (200 m/pixel), Earth‐based P band data. Situated within the heat‐producing potassium, rare earth element, and phosphorus terrane, Mare Imbrium experienced some of the most long‐lived (and recent) lunar volcanism, and its surface exhibits a significant diversity of basaltic chemistry. Our investigation identifies at least four distinct stages of volcanic activity, originating from multiple sources within Imbrium. The most recent of these stages comprises extensive, yet relatively thin volcanic flow units that left remnant kipukas of older mare material distributed across much of the basin. From a future mission perspective, it may be possible to collect samples expressing a wide range in age from small areas of Mare Imbrium. Our map also places important constraints on the interpretation of the Chang'e‐3 Lunar Penetrating Radar measurements.
Dynamic patterns of nitrogen: Phosphorus ratios in forest soils of China under changing environment
Authors: Chen Leiyi , Li Pin , Yang Yuanhe
Published: August 2016

Knowledge of nitrogen (N) and phosphorus (P) stoichiometry is essential for understanding biogeochemical cycle and ecosystem functioning. However, large‐scale patterns in soil stoichiometry are not yet fully understood along environmental gradients nor over the temporal scale. Using a comprehensive data set and artificial neural network approach, we evaluated spatial and temporal patterns in topsoil N and P concentrations and N:P ratio across China's forests. Our results revealed that soil weathering stage, climatic factors (i.e., temperature and precipitation), and forest types jointly explained approximately 34.1% and 30.4% of spatial variations in soil N and P, respectively. By contrast, only precipitation could explain the variation in N:P ratio, with soil N:P ratio exhibiting a trend of increase along the precipitation gradient. The observed spatial patterns in soil N:P ratio were consistent with previous findings derived from plants and microbes, suggesting that variation in precipitation may induce the imbalance of N:P stoichiometry in forest ecosystems. Our results also indicated that topsoil N:P ratios exhibited a significant increase from the 1980s to 2000s. However, the associations of N:P dynamics with a single element largely depended on forest type. In evergreen forests, soil N:P dynamics were caused by increasing N and decreasing P. Conversely, N:P changes in deciduous broadleaf forests were triggered only by soil N accumulation. Overall, these results demonstrated a stoichiometric shift in soil N:P both spatially and temporally, implying that nutrient imbalance between soil N and P may be accelerated under global change scenarios.
Age‐dependent effects of APOE ε4 in preclinical Alzheimer's disease
Authors: Bonham Luke W. , Geier Ethan G. , Fan Chun C. , Leong Josiah K. , Besser Lilah , Kukull Walter A. , Kornak John , Andreassen Ole A. , Schellenberg Gerard D. , Rosen Howard J. , Dillon William P. , Hess Christopher P. , Miller Bruce L. , Dale Anders M. , Desikan Rahul S. , Yokoyama Jennifer S.
Published: August 2016

Objective

The ε4 allele of apolipoprotein E (APOE) is the strongest known common genetic risk factor for Alzheimer's disease (AD) and alters age of onset in retrospective studies. Here, we longitudinally test the effects of APOE ε4 genotype and age during progression from normal cognition to AD.

Methods

Using data from 5381 cognitively normal older individuals and Cox proportional hazards models, we longitudinally tested the effects of APOE genotype on progression from normal cognition to mild cognitive impairment (MCI) or AD in four age strata (<60, 60–70, 70–80, 80 + ) and with a sliding window approach between ages 60 and 85.

Results

We found that APOE ε4 carrier status and dosage significantly influenced progression to MCI or AD in all four age groups and that APOE ε4‐associated progression risk peaked between ages 70 and 75. We confirmed APOE ε4‐associated progression risk in a subset of the cohort with pathologically proven diagnoses.

Interpretation

Our findings indicate that in clinically normal individuals, APOE ε4 status significantly predicts progression to MCI or AD across older adulthood and that this risk varies with age. This information will be useful as therapeutic interventions become available and clinical decisions can be individually tailored based on age and genetic data.
Development of the American College of Rheumatology's Rheumatoid Arthritis Electronic Clinical Quality Measures
Authors: Yazdany Jinoos , Robbins Mark , Schmajuk Gabriela , Desai Sonali , Lacaille Diane , Neogi Tuhina , Singh Jasvinder A. , Genovese Mark , Myslinski Rachel , Fisk Natalie , Francisco Melissa , Newman Eric
Published: August 2016

Objective

Electronic clinical quality measures (eCQMs) rely on computer algorithms to extract data from electronic health records (EHRs). On behalf of the American College of Rheumatology (ACR), we sought to develop and test eCQMs for rheumatoid arthritis (RA).

Methods

Drawing from published ACR guidelines, a working group developed candidate RA process measures and subsequently assessed face validity through an interdisciplinary panel of health care stakeholders. A public comment period followed. Measures that passed these levels of review were electronically specified using the quality data model, which provides standard nomenclature for data elements (category, datatype, and value sets) obtained through an EHR. For each eCQM, 3 clinical sites using different EHR systems tested the scientific feasibility and validity of measures. Measures appropriate for accountability were presented for national endorsement.

Results

Expert panel validity ratings were high for all measures (median 8–9 of 9). Health system performance on the eCQMs was 53.6% for RA disease activity assessment, 69.1% for functional status assessment, 93.1% for disease‐modifying antirheumatic drug (DMARD) use, and 72.8% for tuberculosis screening. Kappa statistics, which evaluated whether the eCQM validly captured data obtained from manual EHR chart review, demonstrated moderate to substantial agreement (0.54 for functional status assessment, 0.73 for tuberculosis screening, 0.84 for disease activity, and 0.85 for DMARD use).

Conclusion

Four eCQMs for RA have achieved national endorsement and are recommended for use in federal quality reporting programs. Implementation and further refinement of these measures is ongoing in the ACR's registry, the Rheumatology Informatics System for Effectiveness (RISE).
Concordance of Patient‐Reported Joint Symptoms, Physician‐Examined Arthritic Signs, and Ultrasound‐Detected Synovitis in Rheumatoid Arthritis
Authors: Hirata Ayako , Ogura Takehisa , Hayashi Norihide , Takenaka Sayaka , Ito Hideki , Mizushina Kennosuke , Fujisawa Yuki , Yamashita Naoko , Nakahashi Sumie , Imamura Munetsugu , Kujime Rie , Kameda Hideto
Published: August 2016

Objective

Ultrasonography has been prevalently used as a valid and objective modality for joint examination in patients with rheumatoid arthritis (RA). This study aimed to examine and compare the concordance between ultrasound, clinical assessment, and patient‐reported assessment of joint synovitis in RA.

Methods

Fifty patients with RA (84% female, median age 69 years, median disease duration 31 months, and median Disease Activity Score in 28 joints 3.8) completed the self‐evaluation of joint symptoms, including pain and considerable stiffness in the (proximal) interphalangeal, metacarpophalangeal, wrist, elbow, shoulder, knee, and ankle joints. These joints were also examined by a physician in order to assess the presence of tenderness or swelling; the presence of imaging synovitis was assessed by ultrasonography.

Results

In a total of 1,492 evaluated joints, symptoms (pain and stiffness), tenderness, and swelling were noted in 288 (19.3%), 182 (12.2%), and 220 (14.7%) joints, respectively, while ultrasound indicated synovitis in 317 (21.2%) joints. Overall concordance with ultrasound findings was lowest for joint tenderness (κ = 0.30), followed by symptoms (κ = 0.39), and by swelling (κ = 0.43), irrespective of the evaluated joint, except for the elbow. Moreover, the percentages of inflamed joints detected only on the basis of symptoms, tenderness, or swelling were 18.6%, 2.2%, and 8.5%, respectively, of all joints with signs of synovitis on ultrasonography.

Conclusion

Joint swelling showed the best concordance with ultrasonography, followed by patient‐reported joint symptoms, and joint tenderness. Joint symptoms, rather than tenderness evaluation, may be a better clinical indicator of synovitis in RA patients.
Clinical Spectrum of Medium‐Sized Vessel Vasculitis
Authors: Alibaz‐Oner Fatma , Koster Matthew J. , Crowson Cynthia S. , Makol Ashima , Ytterberg Steven R. , Salvarani Carlo , Matteson Eric L. , Warrington Kenneth J.
Published: August 2016

Objective

Polyarteritis nodosa (PAN) is a systemic necrotizing vasculitis of medium‐sized visceral vessels. However, cutaneous arteritis (CA) and gastrointestinal (GI) vasculitis are forms of single‐organ vasculitis having indistinguishable histopathologic findings from PAN. The aim of this study was to evaluate and compare the clinical characteristics, treatment, and outcomes of patients with systemic PAN, CA, and GI vasculitis.

Methods

Retrospective cohorts were assembled, consisting of patients with PAN, CA, and GI vasculitis between 1980 and 2014. The demographics, clinical characteristics, treatment, and outcomes of patients were abstracted from medical records.

Results

We included 48 patients with PAN, 41 patients with CA, and 19 patients with GI vasculitis. The disease of 1 patient evolved from CA to systemic PAN during the disease course. At diagnosis, 94% of patients with PAN, 93% of patients with CA, and 67% of patients with GI vasculitis were treated with glucocorticoids. Additional immunosuppressive agents were used in 67% of PAN, 37% of GI vasculitis, and 32% of CA cases. The 5‐year cumulative relapse rate was 45.2% in CA, and only 9.6% in PAN during a followup of approximately 6 years. No deaths were observed in the CA group. The survival rate at 10 years was 66% in the PAN group and 61% in the GI vasculitis group.

Conclusion

Systemic PAN, CA, and GI vasculitis take different clinical courses and therefore may be different diseases, rather than existing on a spectrum of the same disease. Progression of CA to systemic PAN is very rare. Relapse risk is low during followup in PAN. Patients with CA have a higher relapse rate than those with systemic PAN, possibly due to less use of immunosuppressive therapy in CA.
Secular Changes in Clinical Features at Presentation of Rheumatoid Arthritis: Increase in Comorbidity But Improved Inflammatory States
Authors: Nikiphorou Elena , Norton Sam , Carpenter Lewis , Dixey Josh , Andrew Walsh David , Kiely Patrick , Young Adam ,   on behalf of the Early Rheumatoid Arthritis Study and the Early Rheumatoid Arthritis Network Cohorts
Published: August 2016

Objective

To examine secular trends in demographics, clinical manifestations, and comorbidity on first presentation of rheumatoid arthritis (RA) prior to disease‐modifying antirheumatic drug treatment.

Methods

A total of 2,701 patients were recruited over 25 years to 2 UK‐based RA inception cohorts: the Early Rheumatoid Arthritis Study (9 centers; 1986–2001) and the Early Rheumatoid Arthritis Network (23 centers; 2002–2012). Trends in demographic and baseline clinical/laboratory and radiographic variables and comorbidities were estimated using mixed‐effects models, including random effects for recruitment center.

Results

Age at onset increased from 53.2 to 57.7 years in 1990 and 2010, respectively (2.6 months/year; 95% confidence interval [95% CI] 1.2, 4.1). Sex ratio, the proportion living in deprived areas, and smoking status were unchanged (P > 0.05) and there were no changes in the proportion seropositive or erosive at baseline (P > 0.05). After controlling for treatment at the time of assessment, erythrocyte sedimentation rate decreased and hemoglobin increased over time (P > 0.05); however, the Health Assessment Questionnaire (HAQ), the Disease Activity Score (DAS), the DAS in 28 joints, and joint counts were unchanged (P > 0.05). The overall prevalence of comorbidity increased from 29.0% in 1990 to 50.7% in 2010, mainly due to cardiovascular and non‐cardiac vascular conditions, including hypertension. There was a significant increase in body mass index (0.15 units/year; 95% CI 0.11, 0.18), resulting in an increase in the prevalence of obesity from 13.3% in 1990 to 33.6% in 2010.

Conclusion

Age at onset and comorbidity burden, especially obesity, have increased at RA presentation over 25 years, reflecting wider demographic trends at the population level. In contrast, there were no accompanying changes in disease severity assessed by composite markers of disease activity, radiographic erosions, seropositivity, or HAQ at presentation. Treatment strategies in early RA should take greater account of the impact of comorbidity on outcomes.
2017 Clinical trials update: Innovations in hemophilia therapy
Authors: Hartmann Jan , Croteau Stacy E.
Published: August 2016

A surge in therapeutic clinical trials over recent years is paving the way for transformative treatment options for patients with hemophilia. The introduction of recombinant factor concentrates in the early 1990s facilitated the use of prophylactic replacement as standard care for hemophilia rather than on‐demand treatment. This has revolutionized health outcomes for hemophilia patients, enabling participation in physical activities and reducing debilitating, chronic joint damage. Challenges of prophylactic factor infusion include the frequency of infusions needed to maintain factor levels greater than 1%, patient adherence, reliable intravenous access, and development of neutralizing alloantibodies (“inhibitors”). Novel therapeutics seek to improve upon current factor concentrates by several different mechanisms: (1) extending the half‐life of circulating exogenous factor protein, (2) replacing the gene necessary for production of endogenous factor protein, (3) employing bispecific antibody technology to mimic the coagulation function of factor VIII, (4) disrupting anticoagulant proteins, such as tissue factor pathway inhibitor (TFPI) or antithrombin (AT3) with antibodies, aptamers, or RNA interference technology. Emerging treatment options may reduce the frequency of (extended half‐life products) or eliminate (gene therapy) the need for scheduled factor concentrate infusions, or provide a subcutaneous administration option (bispecific antibody, AT3, and TFPI targeting therapies). In addition, the nonfactor replacement strategies provide a promising treatment option for patients with inhibitors, presently the greatest unmet medical need in hemophilia. This review highlights current and recently completed clinical trials that are driving a paradigm shift in our approach to hemophilia care for patients with and without inhibitors. Am. J. Hematol. 91:1252–1260, 2016. © 2016 Wiley Periodicals, Inc.
Mean telomere length is not associated with current health status in a 50‐year‐old population sample
Authors: Appleby Sarah , Pearson John F. , Aitchison Alan , Spittlehouse Janet K. , Joyce Peter R. , Kennedy Martin A.
Published: August 2016

Objectives

Telomeres are nucleoprotein complexes that cap the ends of linear chromosomes. Telomeric DNA decreases with age and shows considerable heterogeneity in the wider population. There is interest in the application of telomere length measures as a biomarker of general health or “biological age,” and the possibility of using mean telomere length to gauge individual disease risk, and to promote lifestyle changes to improve health. This study examined the effectiveness of telomere length as a biomarker for an individual's current overall health status by assessing several measures of general health including SF‐36v2 score, current smoking status and a comprehensive obesity phenotype.

Methods

Participants were from the Canterbury Health, Ageing and Lifecourse (CHALICE) cohort, a New Zealand population based multidisciplinary study of aging. Telomere length measurements were obtained on DNA from peripheral blood samples at age 49–51 (n = 351), using a quantitative polymerase chain reaction assay.

Results

No associations were found between telomere length measured at age 49–51 and any measures of current health status. The only significant association observed was between telomere length and gender, with females having longer telomere length than men.

Conclusions

Our results suggest that telomere length measurements are unlikely to provide information of much predictive significance for an individual's health status.
Minimal energetic expenditure of women walking burdened on gradients in urban environments
Authors: Rue Megan J. , Kramer Patricia A.
Published: August 2016

Objectives

The objective is to understand the walking energy expenditure of women in urban environments (i.e., over‐ground), using mass, velocity, gradient (incline and decline), and burden as predictors. In addition, we use an equation to determine the gradient associated with the minimum energy expenditure of walking.

Methods

To do this, we assessed the volumetric consumption of oxygen (VO2) of ten females (ages: 22–40 years) with a portable Cosmed K4b2 device. Participants walked at three self‐selected, over‐ground velocities (slow, normal, and fast) on five gradients (0%, +/−7.5%, +/− 12.4%) in different urban community settings burdened (10 kg) and unburdened. We performed a multilinear regression controlling for repeated measures to determine the best predictive equation for VO2. The first derivative of our equation was used to find the gradient for minimal VO2.

Results

Our equation explains 79% of the variation in VO2 and indicates that over‐ground walking is similar to treadmill walking, except that the gradient associated with the minimal energy expenditure of walking is steeper (−11% to −20%) than that established from treadmill walking.

Conclusions

Although our overall equation is an accurate predictor of VO2 for all velocities, burden, incline, and decline in this group, further research needs to be conducted to examine kinetic, kinematic, and velocity interactions in over‐ground walking.
A case report of systemic embolic events associated with atrial fibrillation
Authors: Nakano Hidehiko , Yamagami Hiroshi , Ofuchi Hisashi
Published: August 2016

Case

An 82‐year‐old woman who had atrial fibrillation was found unconscious and was brought to the emergency department by ambulance. Her Glasgow Coma Scale score was 3, and an electrocardiogram showed ST segment elevation in V3 and V4. Cardiac ultrasonography showed left ventricular asynergy in the anterior wall, septum, and apex. Although dissection of the aorta was suspected, contrast computed tomography showed multiple arterial thromboses, including bilateral common carotid arteries and poor contrast in the left ventricle. Diffusion‐weighted images of magnetic resonance imaging showed a diffuse high‐intensity area in both cerebral cortices.

Outcome

The diagnosis was multiple arterial thromboembolisms associated with atrial fibrillation. There was no available treatment because of massive multiple lesions and the patient died within 24 h of presentation.

Conclusion

Extracranial systemic embolic events other than cerebral embolism could be critical complications associated with atrial fibrillation.
Wohldefinierte polymere Paclitaxel‐Prodrugs über eine Grafting‐From‐Methode ausgehend vom Arzneistoff
Authors: Louage Benoit , Nuhn Lutz , Risseeuw Martijn D. P. , Vanparijs Nane , De Coen Ruben , Karalic Izet , Van Calenbergh Serge , De Geest Bruno G.
Published: August 2016

Ein polymeres Prodrug‐Konzept für das Chemotherapeutikum Paclitaxel (PTX) basierend auf einer Grafting‐From‐Methode ausgehend vom Arzneistoff wird vorgestellt. Ein Kettentransferreagenz für die reversible Additions‐Fragmentierungs‐Kettentransferpolymerization (RAFT) wurde mit hoher Ausbeute und Regioselektivität an die für seine Bioaktivität entscheidende C2′‐Position von Paclitaxel angebunden. Nach anschließender RAFT‐Polymerization mit einem hydrophilen Monomer konnten wohldefinierte Paclitaxel‐Polymer‐Konjugate erhalten werden, die eine hohe Wirkstoffbeladung, Wasserlöslichkeit und Stabilität aufweisen. Die Vielseitigkeit der Methode konnte weiterhin durch ω‐Endgruppenmodifizierung des Polymers mit einem Fluoreszenzmarker demonstriert werden. In In‐vitro‐Experimenten wurden diese Konjugate bereitwillig von Zellen in deren Endosome aufgenommen, von wo aus das native PTX ergiebig freigesetzt wurde und an seine subzellulären Wirkorte gelangte. Dies konnte über das Zytotoxizitätsprofil des Konjugats bestätigt werden, da es mit den kommerziellen PTX‐Formulierungen übereinstimmt, die nur auf einfachen physikalischen Verkapselungen beruhen.
Dynamic optimization of trajectory for ramp‐up current profile in tokamak plasma
Authors: Ren Zhigang , Xu Chao , Ou Yongsheng
Published: August 2016

In this paper, we consider an open‐loop, finite‐time, optimal control problem of attaining a specific desired current profile during the ramp‐up phase by finding the best open‐loop actuator input trajectories. Average density, total power, and plasma current are used as control actuators to manipulate the profile shape in tokamak plasmas. Based on the control parameterization method, we propose a numerical solution procedure directly to solve the original partial differential equation (PDE)‐constrained optimization problem using gradient‐based optimization techniques such as sequential quadratic programming. This paper is aimed at proposing an effective framework for the solution of PDE‐constrained optimization problem in tokamak plasmas. A more user‐friendly and efficient graphical user interface is designed in MATLAB, and the numerical simulation results are verified to demonstrate its applicability. In addition, the proposed framework of combining existing PDE and numerical optimization solvers to solve PDE‐constrained optimization problem has the prospective to target challenge advanced control problems arising in more general chemical engineering processes. © 2016 Curtin University of Technology and John Wiley & Sons, Ltd.
Preparation of a ferrocene mediated bioanode for biofuel cells by MWCNTs, polyethylenimine and glutaraldehyde: glucose oxidase immobilization and characterization
Authors: Bahar Tahsin
Published: August 2016

Ferrocene groups introduced polyethylenimine was adsorbed onto multi‐wall carbon nanotubes attached carbon cloth before crosslinking via glutaraldehyde to develop an enzyme electrode (anode) for biofuel cell applications. Glucose oxidase was covalently immobilized onto this electrode by leftover aldehyde groups on the surface. The apparent Michaelis constant of immobilized enzyme was measured as approximately fivefold higher than that of the free enzyme. Thermal stability of immobilized enzyme was improved as estimated. Activity half‐life of the immobilized glucose oxidase was determined as approximately 8 times longer than that of the free one; 2.4 mA/cm2 electrical current was obtained by using this electrode by forming a basic biofuel half‐cell. Copyright © 2016 Curtin University of Technology and John Wiley & Sons, Ltd.
Layer thickness impact on the capacity of poly(urethaneimide) for sorbing toxic gases
Authors: Kolev Iliyan , Alexieva Gergana , Strashilov Vesselin , Youssef Ismail Ben , Sarry Frederic , Alem Halima
Published: August 2016

The sensitivity of a thick layer (500 nm) of poly(urethaneimide) to toxic gases such as pyridine and hexamethyleneimine was studied by the quartz crystal microbalance method. The resonant frequency was registered by a spectrum analyzer. The successful overcoming of the unfavorable impact of the increased viscous damping, typical for the standard oscillator measurement method, allowed complete understanding of the behavior of a thick polymer layer toward highly pollutant gases. Quantitative information for polymer adsorption capacity and gas diffusivity was extracted. The comparison with our recent results for thinner layers revealed strong dependence on layer thickness for pyridine whereas the corresponding effect with hexamethyleneimine was found much less significant. Intermolecular interactions and the impact of the gas physical adsorption on the polymer matrix properties were shown as the driving parameters for the sensors response. The thickness dependence provides a tool for tuning the sensitivity of a potentially efficient poly(urethaneimide) sensor for pyridine. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44214.
Controlling micro‐ and nanofibrillar morphology of polymer blends in low‐speed melt spinning process. Part III: Fibrillation mechanism of PLA/PVA blends along the spinline
Authors: Tran Nguyen Hoai An , Brünig Harald , Auf der Landwehr Maria , Heinrich Gert
Published: August 2016

The effects of spinning conditions on the fibrillation process of poly(lactic acid) (PLA) and poly(vinyl alcohol) (PVA) polymer blends in an elongational flow within the fiber formation zone are systematically and thoroughly investigated. By considering the relationship between the changes in filament parameters with the focus on the maximum axial strain rate (ASR) and tensile stress at maximum ASR and the morphological evolution of the dispersed PLA phase along the spinline, the fibrillation process from rod‐like to nanofibrillar structures of the dispersed PLA phase in a binary blend with PVA matrix is elucidated. The final morphology of the dispersed PLA phase in PLA/PVA blends is controlled by the changes in the spinning conditions. The lengths and diameters of the PLA fibrils are caused not only by the deformation of their initial sizes but also by the combination of the deformation, coalescence, and break‐up process. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44259.
Facile fabrication of double‐walled polymeric hollow spheres with independent temperature and pH dual‐responsiveness for synergetic drug delivery
Authors: Cheng Nan , Wang Yu , Wu Feipeng
Published: August 2016

A dual‐responsive double‐walled polymeric hollow sphere (PHS) serving as a candidate for synergetic drug delivery platform is prepared by a simple and green template polymerization in aqueous medium. The PHS, comprised of thermo‐responsive crosslinked poly(N‐isopropylacrylamide) (PNIPAM) as the inner shell and pH‐responsive crosslinked poly(methacrylic acid) (PMAAc) as the outer shell, is assembled through self‐removal of the thermo‐responsive template from a core‐triple shell structure by free radical polymerization with sequential addition of reactants. The discrete double‐shell structure renders the PHS independent temperature and pH‐controlled swelling/shrinking capability. Taking the advantage of two compartmentalized internal spaces (the core and the interlayer spaces) with independent temperature‐ and pH‐dependent behaviors, two model drugs representing the small molecule and the macromolecule are loaded in selective locations of the PHS. Two drugs show dramatically different release profiles according to environmental temperature and pH, due to the localization of drugs and the stimuli‐dependent property of its protective shells. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44335.