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Japanese larch (Larix kaempferi (Lamb.) Carr.) and its hybrid are economically important coniferous trees widely grown in the Northern Hemisphere. Ground-level ozone (O3) concentrations have increased since the pre-industrial era, and research projects showed that Japanese larch is susceptible to elevated O3 exposures. Therefore, methodologies are needed to (1) protect Japanese larch against O3 damage and (2) conduct biomonitoring of O3 in Japanese larch forests and, thus, monitor O3 risks to Japanese larch. For the first time, this study evaluates whether the synthetic chemical ethylenediurea (EDU) can protect Japanese larch against O3 damage, in two independent experiments. In the first experiment, seedling communities, simulating natural regeneration, were treated with EDU (0, 100, 200, and 400 mg L−1) and exposed to either ambient or elevated O3 in a growing season. In the second experiment, individually-grown saplings were treated with EDU (0, 200 and 400 mg L−1) and exposed to ambient O3 in two growing seasons and to elevated O3 in the succeeding two growing seasons. The two experiments revealed that EDU concentrations of 200–400 mg L−1 could protect Japanese larch seedling communities and individual saplings against O3-induced inhibition of growth and productivity. However, EDU concentrations ≤ 200 mg L−1 did offer only partial protection when seedling communities were coping with higher level of O3-induced stress, and only 400 mg EDU L−1 fully protected communities under higher stress. Therefore, we conclude that among the concentrations tested the concentration offering maximum protection to Japanese larch plants under high competition and O3-induced stress is that of 400 mg EDU L−1. The results of this study can provide a valuable resource of information for applied forestry in an O3-polluted world.

Purpose Revision constrained-condylar total knee arthroplasty (CCK-TKA) is often used to provide additional mechanical constraint after failure of a primary TKA. However, it is unknown how much this translates to a reliance on soft-tissue support. The aim of this study was therefore to compare the laxity of a native knee to the CCK-TKA implanted state and quantify how medial soft-tissues stabilise the knee following CCK-TKA. Methods Ten intact cadaveric knees were tested in a robotic system at 0°, 30°, 60° and 90° flexion with ± 90 N anterior–posterior force, ± 8 Nm varus-valgus and ± 5 Nm internal–external torques. A fixed-bearing CCK-TKA was implanted and the laxity tests were repeated with the soft tissues intact and after sequential cutting. The deep and superficial medial collateral ligaments (dMCL, sMCL) and posteromedial capsule (PMC) were sequentially transected and the percentage contributions of each structure to restraining the applied loads were calculated. Results Implanting a CCK-TKA did not alter anterior–posterior laxity from that of the original native knee, but it significantly decreased internal–external and varus-valgus rotational laxity (p Conclusions With a fully-competent sMCL in-vitro, a fixed-bearing CCK-TKA knee provided more rotational constraint than the native knee. The robotic test data showed that both the soft-tissues and the semi-constrained implant restrained rotational knee laxity. Therefore, in clinical practice, a fixed-bearing CCK-TKA knee could be indicated for use in a knee with lax, less-competent medial soft tissues. Level of evidence Controlled laboratory study.

Hip resurfacing is an attractive alternative to total hip replacement preserving bone and reducing dislocation risk. Recent metal-on-metal designs have caused failure due to metal wear debris. Ceramic implants may mitigate this risk. Deformation of the acetabular cup can affect the lubrication, producing high friction torques between the femoral head and the cup that would increase wear and/or lead to cup loosening due to femoral head clamping. Our objective was to quantify the deformation of a novel monobloc ceramic hip resurfacing cup component compared to a metal standard, in a fresh frozen cadaveric model using a press-fit technique representative of standard surgical conditions. For this study eight acetabula were prepared from four fresh frozen cadavers. One surgeon with extensive experience in hip resurfacing surgery (J.H.) prepared the acetabulum by sequential reaming. The implants were then impacted into the acetabulum. Four ceramic and four metal implants were used of equal and varying size. Deformation was measured peri-implantation, and at 30 min, using an optical high-precision deformation sensor (GOM GmbH, Braunschweig, Germany). The maximum inscribed circle and the measurement of radial segment techniques were used. Deformation was greater in the metal implants (mean: 34–22mm) immediately after implantation. At 30 min after implantation, the deformation increased to 36mm in the metal and 26mm in the ceramic cup. Greater diameter changes were observed in larger cups. Metal and ceramic implants did not return to the initial diameter. We conclude the ceramic resurfacing acetabular implants undergo similar deformation to existing metal-on-metal implants. The deformation observed was significantly less in the ceramic component at 30 min on one measure. Less deformation may result in better surface conditions and wear characteristics. Deformation change did not resolve after 30 min for both implants.

To investigate the effects of elevated atmospheric CO2 concentrations ([CO2]) on autumnal phenology and end of season photosynthesis of different bud-break leaves of trees, we fumigated 2-year-old red maple seedlings with 800, 600, and 400 μL L−1 [CO2] in nine continuous stirred tank reactor (CSTR) chambers. Leaves were subdivided into first (B1), second (B2), and third bud-break (B3) leaves. The results indicated that (1) autumnal leaf senescence, including the beginning date, end date, and duration of leaf abscission of all three bud-break leaf groups, was not affected by elevated [CO2]; (2) elevated [CO2] increased leaf photosynthesis of B1, B2, and B3 leaves throughout the whole of the growing season; (3) elevated [CO2] significantly increased whole plant photosynthesis only for B2 leaves, accounting for 41.2–54.7% of the whole plant photosynthesis, due to the larger whole leaf area of B2. In conclusion, enhanced seasonal carbon gain in response to atmospheric CO2 enrichment is the result of strong stimulation of photosynthesis throughout the growing season, especially for B2 leaves but not by extending or shortening the growing season in autumn.

To investigate the effects of atmospheric CO2 enrichment on physiology and autumnal leaf phenology, we exposed 3-year-old sugar maple (Acer saccharum Marsh.) seedlings to 800 (A8), 600 (A6), and 400 μL(CO2) L–1 (AA) in nine continuous stirred tank reactor (CSTR) chambers during the growing season of 2014. Leaf abscission timing, abscised leaf area percentages, leaf number, light-saturated net photosynthetic rate (PNmax), leaf area, accumulative growth rates, and biomass were determined and assessed. The results suggested the following: (1) no significant differences were found in the timing of leaf abscission in the three CO2-concentration treatments; (2) PNmax was continuously stimulated to the greatest extent in A8 at 319% and 160% in A6 until the end of the growing season, respectively; and (3) leaf number, leaf area, and accumulative height growth all significantly increased by elevated CO2, which led to a 323% increase in A8 biomass and 235% in A6 biomass after 156-d fumigation. In summary, the results suggest, the timing of leaf abscission of sugar maple in fall was not modified by CO2 enrichment, the increased carbon gain by elevated CO2 was mainly due to increased leaf area, more leaves, and the continuously enhanced high photosynthesis throughout the growing season instead of the leaf life span.

Monitoring of ozone damage to crops plays an increasingly important role for the food security of many developing countries. Ethylenediurea (EDU) could be a tool to assess ozone damage to vegetation on field scale, but its physiological mode of action remains unclear. This study investigated mechanisms underlying the ozone-protection effect of EDU in controlled chamber experiments. Ozone sensitive and tolerant rice genotypes were exposed to ozone (108 ppb, 7 hr day-1 ) and control conditions. EDU alleviated ozone effects on plant morphology, foliar symptoms, lipid peroxidation, and photosynthetic parameters in sensitive genotypes. Transcriptome profiling by RNA sequencing revealed that thousands of genes responded to ozone in a sensitive variety, but almost none responded to EDU. Significant interactions between ozone and EDU application occurred mostly in ozone responsive genes, in which up-regulation was mitigated by EDU application. Further experiments documented ozone degrading properties of EDU, as well as EDU deposits on leaf surfaces possibly related to surface protection. EDU application did not mitigate the reaction of plants to other abiotic stresses, including iron toxicity, zinc deficiency, and salinity. This study provided evidence that EDU is a surface protectant that specifically mitigates ozone stress without interfering directly with the plants' stress response systems.

Modular uncemented acetabular components are in common use. Fixation is dependent upon press-fit but the forces necessary to achieve initial stability of the construct at implantation may deform the shell and prevent optimal seating of the polyethylene liner insert. Previous work using single-time point measurements in uncontrolled ambient temperature poorly replicates the native state. A controlled study was performed to observe the time-dependent behaviour of an uncemented acetabular shell in the early phase after implantation into the human acetabulum at near physiological temperature. Using a previously validated cadaveric hip model at controlled near physiological temperature with standardised surgical technique, immediate and delayed shell geometry was determined. Eight custom made 3-mm-thick titanium alloy (TiAl6V4) shells were implanted into four cadavers (eight hips). Time-dependent shell deformation was determined using the previously validated ATOS Triple Scan III (ATOS) optical measurement system. The pattern of change in the shape of the surgically implanted shell was measured at three time points after insertion. We found a consistent pattern for quantitative and directional deformation of the shells. In addition, there was consistency for relaxation of the deformation with time. Immediate mean change in shell radius was 104 µm (standard deviation 32, range 67–153) relaxing to mean 96 µm (standard deviation 32, range 63–150) after 10 min and mean 92 µm (standard deviation 28, range 66–138) after 20 min. The clinical significance of this work is the finding of a time-dependent early deformation of acetabular titanium shells on insertion adjusted for near physiological temperature-controlled host bone.

Ground-level ozone (O3) concentrations have been elevating in the last century. While there has been a notable progress in understanding O3 effects on vegetation, O3 effects on ecological stoichiometry remain unclear, especially early in the oxidative stress. Ethyelenediurea (EDU) is a chemical compound widely applied in research projects as protectant of plants against O3 injury, however its mode of action remains unclear. To investigate O3 and EDU effects early in the stress, we sprayed willow (Salix sachalinensis) plants with 0, 200 or 400 mg EDU L−1, and exposed them to either low ambient O3 (AOZ) or elevated O3 (EOZ) levels during the daytime, for about one month, in a free air O3 controlled exposure (FACE); EDU treatment was repeated every nine days. We collected samples for analyses from basal, top, and shed leaves, before leaves develop visible O3 symptoms. We found that O3 altered the ecological stoichiometry, including impacts in nutrient resorption efficiency, early in the stress. The relation between P content and Fe content seemed to have a critical role in maintaining homeostasis in an effort to prevent O3-induced damage. Photosynthetic pigments and P content appeared to play an important role in EDU mode of action. This study provides novel insights on the stress biology which are of ecological and toxicological importance.

To gain initial stability for cementless fixation the acetabular components of a total hip replacement are press-fit into the acetabulum. Uneven stiffness of the acetabular bone will result in irregular deformation of the shell which may hinder insertion of the liner or lead to premature loosening. To investigate this, we removed bone cores from the ilium, ischium and pubis within each acetabulum and from selected sites in corresponding femoral heads from four cadavers for mechanical testing in unconfined compression. From a stress-relaxation test over 300 s, the residual stress, its percentage of the initial stress and the stress half-life were calculated. Maximum modulus, yield stress and energy to yield (resilience) were calculated from a load-displacement test. Acetabular bone had a modulus about 10–20%, yield stress about 25% and resilience about 40% of the values for the femoral head. The stress half-life was typically between 2–4 s and the residual stress was about 60% of peak stress in both acetabulum and femur. Pubic bone was mechanically the poorest. These results may explain uneven deformation of press-fit acetabular shells as they are inserted. The measured half-life of stress-relaxation indicates that waiting a few minutes between insertion of the shell and the liner may allow seating of a poorly congruent liner.

Ground-level ozone (O₃) levels are nowadays elevated in wide regions of the Earth, causing significant effects on plants that finally lead to suppressed productivity and yield losses. Ethylenediurea (EDU) is a chemical compound which is widely used in research projects as phytoprotectant against O₃ injury. The EDU mode of action remains still unclear, while there are indications that EDU may contribute to plants with nitrogen (N) when the soil is poor in N and the plants have relatively small leaf area. To reveal whether the N content of EDU acts as a fertilizer to plants when the soil is not poor in N and the plants have relatively large total plant leaf area, willow plants (Salix sachalinensis Fr. Schm) were exposed to low ambient O₃ levels and treated ten times (9-day interval) with 200 mL soil drench containing 0, 800 or 1600 mg EDU L⁻¹. Fertilizer was added to a nutrient-poor soil, and the plants had an average plant leaf area of 9.1 m² at the beginning of EDU treatments. Indications for EDU-induced hormesis in maximum electron transport rate (Jmax) and ratio of intercellular to ambient CO₂ concentration (Ci:Cₐ) were observed at the end of the experiment. No other EDU-induced effects on leaf greenness and N content, maximum quantum yield of photosystem II (Fv/Fm), gas exchange, growth and matter production suggest that EDU did not act as N fertilizer and did not cause toxicity under these experimental conditions.

Hip resurfacing is an attractive alternative to total hip replacement preserving bone and reducing dislocation risk. Recent metal-on-metal designs have caused failure due to metal wear debris. Ceramic implants may mitigate this risk. Temperature increase in periprosthetic bone during cementation can lead to osteonecrosis, while deformation of the component can affect joint lubrication and may increase wear through clamping. Both processes may lead to implant loosening. This study quantifies the temperature and deformation change in a novel ceramic hip resurfacing femoral component compared to a metal standard during cemented implantation in a fresh frozen cadaveric model. Study design and methods Eight femora were prepared from four fresh frozen cadavers. One surgeon experienced in hip resurfacing surgery (J.H.) prepared the femora by reaming. Four ceramic and four metal implants of equal and varying size were cemented in place. Bone and surface temperatures were taken using a probe in the periprosthetic bone and an infrared laser thermometer, respectively. Deformation was measured using a micrometre. Measurements were taken before implantation and every 5-min intervals up to 30 min. The average bone-temperature increment was lower for ceramic heads than for metal heads. Although this difference was not statistically significant, the average bone temperature incremental change in small sizes (42 and 46 mm) was higher than in the large sizes (48 and 50 mm). Most metal heads sustained bearing diameter change that was still near its peak value 30 min after implantation, whereas the ceramic heads suffered a lower diameter change and most of the samples recovered their original diameter 30 min after implantation. Both implants behave similarly, however, a lower temperature rise in bone was observed with ceramic heads. This may lower the risk for thermal damage on periprosthetic bone. The ceramic heads deformed less during surgical implantation. This was not significant.

To understand whether the process of seasonal nitrogen resorption and biomass allocation are different in CO2-enriched plants, seedlings of red maple (Acer rubrum L.) were exposed to three CO2 concentrations (800 &micro, L L&minus, 1 CO2 treatments&mdash, A800, 600 &micro, A600, and 400 &micro, A400) in nine continuous stirred tank reactor (CSTR) chambers. Leaf mass per area, leaf area, chlorophyll index, carbon (C), nitrogen (N) contents, nitrogen resorption efficiency (NRE), and biomass allocation response were investigated. The results indicated that: (1) Significant leaf N decline was found in senescent leaves of two CO2 treatments, which led to an increase of 43.4% and 39.7% of the C/N ratio in A800 and A600, respectively. (2) Elevated CO2 induced higher NRE, with A800 and A600 showing significant increments of 50.3% and 46.2%, respectively. (3) Root biomass increased 33.1% in A800 and thus the ratio of root to shoot ratio was increased by 25.8%. In conclusion, these results showed that to support greater nutrient and water uptake and the continued response of biomass under elevated CO2, Acer rubrum partitioned more biomass to root and increased leaf N resorption efficiency.

It is widely accepted that elevated levels of surface ozone(O-3) negatively affect plants. Ethylenediurea (EDU) is a synthetic substance which effectively protects plants against O-3-caused phytotoxicity. Among other questions, the one still open is: which EDU application method is more appropriate for treating fast-growing tree species. The main aims of this study were: (i) to test if chronic exposure of Salix sachalinensis plants to 200-400 mg EDU L-1, the usually applied range for protection against O-3 phytotoxicity, is beneficial to plants; (ii) to evaluate the effects of chronic exposure to elevated O-3 on S. sachalinensis; (iii) to assess the efficacy of two methods (i.e. soil drench and foliar spray) of EDU application to plants; (iv) to investigate the appropriate concentration of EDU to protect against elevated O-3-induced damage in S. sachalinensis; and (v) to compare the two methods of EDU application in terms of effectiveness and EDU consumption. Current-year cuttings grown in infertile soil free from organic matter were exposed either to low ambient O-3 (AOZ, 10-h approximate to 283 nmol mol(-1)) or to elevated O-3 (EOZ, 10-h approximate to 65.8 nmol mol(-1)) levels during daylight hours. Over the growing season, plants were treated every nine days with 200 mL soil drench of 0, 200 or 400 mg.EDU L-1 or with foliar spray of 0, 200 or 400 mg EDU L-1 (in two separate experiments). We found that EDU per se had no effects on plants exposed to AOZ. EOZ practically significantly injured S. sachalinensis plants, and the impact was indifferent between the experiments. EDU did not protect plants against EOZ impact when applied as soil drench but it did protect them when applied as 200-400 mg.L-1 foliar spray. We conclude that EDU may be. more effective against O-3 phytotoxicity to fast-growing species when applied as a spray than when applied as a drench. Key message: Soil-drenched EDU was ineffective in protecting willow plants against O-3-induced injury, whereas foliar-sprayed EDU was effective even at the concentration of 200 mg L-1. (C) 2016 Elsevier B.V. All rights reserved.

Little information is available to surgeons regarding how the lateral structures prevent instability in the replaced knee. The aim of this study was to quantify the lateral soft-tissue contributions to stability following cruciate-retaining total knee arthroplasty (CR TKA). Nine cadaveric knees were tested in a robotic system at full extension, 30°, 60°, and 90° flexion angles. In both native and CR implanted states, ±90 N anterior-posterior force, ±8 Nm varus-valgus, and ±5 Nm internal-external torque were applied. The anterolateral structures (ALS, including the iliotibial band), the lateral collateral ligament (LCL), the popliteus tendon complex (Pop T), and the posterior cruciate ligament (PCL) were transected and their relative contributions to stabilizing the applied loads were quantified. The LCL was found to be the primary restraint to varus laxity (an average 56% across all flexion angles), and was significant in internal-external rotational stability (28% and 26%, respectively) and anterior drawer (16%). The ALS restrained 25% of internal rotation, while the PCL was significant in posterior drawer only at 60° and 90° flexion. The Pop T was not found to be significant in any tests. Therefore, the LCL was confirmed as the major lateral structure in CR TKA stability throughout the arc of flexion and deficiency could present a complex rotational laxity that cannot be overcome by the other passive lateral structures or the PCL. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1902-1909, 2017.

A field study was conducted to evaluate the effects of ambient ozone (O-3) on an O-3-sensitive poplar (Populus cathayana) by using ethylenediurea (EDU) as a chemical protectant under two soil water treatments (well-watered (WW) and moderate drought (MD, 50-60% of WW in volumetric soil water content). EDU was applied as foliar spray at 0, 300, 450, and 600 ppm. Photosynthetic parameters, pigment contents, leaf nitrogen, antioxidant capacity, growth, and biomass were measured. The 8 h (9:00-17:0) average ambient O-3 concentration was 71.7 ppb, and AOT40 was 29.2 ppm h during the experimental period (9 June to 21 September), which was high enough to cause plant injury. MD had significantly negative effects on P. cathayana, as indicated by reduced photosynthesis, growth, and biomass, and higher MDA contents. On the other hand, EDU significantly increased photosynthesis rate, chlorophyll a fluorescence, V-cmax and J(max), photosynthetic pigments, total antioxidant capacity, tree growth and biomass accumulation, and reduced lipid peroxidation, but there was no significant interaction between EDU and drought for most parameters, indicating that EDU can efficiently protect Populus cathayana against ambient O-3 and the protection was not affected by soil water contents when soil water reached moderate drought level. Among all doses, EDU at 450 ppm provided maximum protection. Comparison of EDU-treated and non-treated P. cathayana could be used as a biomarker systemin risk assessment of the effects of ambient O3 on forest health. (C) 2016 Published by Elsevier B.V.

Ethylene diurea (EDU) is synthetic chemical which protects plants against damage caused by ground level O-3 and is used experimentally as a biomonitoring tool at doses usually ranging from 200 to 400 mg L-1 a.i. Although several studies have investigated the protective action of EDU, this mechanism remains unclear. Important uncertainties in EDU action are whether EDU acts as a source of nitrogen (N) to plants and whether high doses are phytotoxic. In order to answer these questions, we conducted an open-field experiment where potted willow (Salix sachalinensis Fr. Schm) plants were exposed to ambient O-3 conditions and treated with 0, 800 or 1600 mg L-1 EDU as a soil drench, every nine days, for about 2.5 months. We examined approximately 50 response variables. Based on N content in different plant organs, we found that (a) all EDU was transferred to the leaves and (b) high doses of EDU increased the leaf N content. However, EDU did not affect the C content and distribution within the plant body. Still, even at the highest dose, EDU was not toxic to this fast-growing species (however such a high dose should not be applied in uncontrolled environments); and there was no EDU persistence in the soil, as indicated by soil N content. Notably, our soil was free from organic matter and N-poor. Key message: EDU per se does not cause toxicity to willow plants when applied as drench to a soil with no organic matter, rather, high EDU doses may act as nitrogen fertilizer in a nitrogen-poor soil. (C) 2016 Elsevier B.V. All rights reserved.

Accurate soft tissue balance must be achieved to improve functional outcome after total knee arthroplasty (TKA). Sensor-integrated tibial trials have been introduced that allow real-time measurement of tibiofemoral kinematics during TKA. This study examined the interplay between tibiofemoral force and laxity, under defined intraoperative conditions, so as to quantify the kinematic behaviour of the CR femoral single-radius knee. TKA was undertaken in eight loaded cadaveric specimens. Computer navigation in combination with sensor data defined laxity and tibiofemoral contact force, respectively, during manual laxity testing. Fixed-effect linear modelling allowed quantification of the effect for flexion angle, direction of movement and TKA implantation upon the knee. An inverse relationship between laxity and contact force was demonstrated. With flexion, laxity increased as contact force decreased under manual stress. Change in laxity was significant beyond 30° for coronal plane laxity and beyond 60° for rotatory laxity (p

Purpose: The aim of this study was to quantify the medial soft tissue contributions to stability following constrained condylar (CC) total knee arthroplasty (TKA) and determine whether a medial reconstruction could restore stability to a soft tissue-deficient, CC-TKA knee. Methods: Eight cadaveric knees were mounted in a robotic system and tested at 0°, 30°, 60°, and 90° of flexion with ±50 N anterior–posterior force, ±8 Nm varus–valgus, and ±5 Nm internal–external torque. The deep and superficial medial collateral ligaments (dMCL, sMCL) and posteromedial capsule (PMC) were transected and their relative contributions to stabilising the applied loads were quantified. After complete medial soft tissue transection, a reconstruction using a semitendinosus tendon graft was performed, and the effect on kinematic behaviour under equivocal conditions was measured. Results: In the CC-TKA knee, the sMCL was the major medial restraint in anterior drawer, internal–external, and valgus rotation. No significant differences were found between the rotational laxities of the reconstructed knee to the pre-deficient state for the arc of motion examined. The relative contribution of the reconstruction was higher in valgus rotation at 60° than the sMCL; otherwise, the contribution of the reconstruction was similar to that of the sMCL. Conclusion: There is contention whether a CC-TKA can function with medial deficiency or more constraint is required. This work has shown that a CC-TKA may not provide enough stability with an absent sMCL. However, in such cases, combining the CC-TKA with a medial soft tissue reconstruction may be considered as an alternative to a hinged implant.

Introduction: Plasma proteins should be useful biomarkers for disease detection, yet few proteins (~120) are FDA approved. Productive biomarker discovery studies are resource-limited due to the complex biochemical fractionation methods used to address the inherent challenges in unbiased plasma profiling such as the large dynamic range. Herein, we describe Proteograph, a novel platform that leverages the nano-bio interactions of nanoparticles (NPs) for deep and unbiased proteomic sampling. NPs reproducibly bind subsets of proteins from biofluids as a function of protein concentration, protein-NP affinity, and protein-protein interactions to form a corona on the NP surface. The corona composition is directly a function of the NPs' biophysicochemical properties and requires no prior knowledge of the proteins that might be selected by each distinctly engineered NP. With an optimized panel of 10 NPs, we can broadly and deeply interrogate the plasma proteome and rapidly quantify potential biomarkers. The highly parallel NP workflow makes large studies practicable and should improve biomarker discovery and validation. Methods and Results: We have screened 200+ NPs with different biophysicochemical properties and selected a panel of 10 based on protein detection. A fully automated assay workflow was developed that can process the 10 NP panel across 8 plasma samples in a 7 hr assay. Evaluation of this panel across 16 individual plasma samples detected 2,009 protein groups (1% protein FDR, 84% with 2 or more peptides). Accuracy was demonstrated with spike-recovery experiments using 4 NPs in which CRP, Angiogenin and S100a8/9 were added to plasma at 2X, 5X, 10X, and 100X of measured endogenous levels. Linear model fits for NP corona MS signal vs. ELISA were created with mean slopes of 1.06 ± 0.22 and mean adjusted-r2 of 0.95 ± 0.05. Precision was demonstrated across 3 NPs using three assay replicates in which the mean of the median CVs for each NP is 24%. The depth of plasma proteome coverage for the 10 NP panel using a pooled plasma sample was determined by comparison of the NP-detected proteins to published MS intensities and spanned nearly the entire reported range. Examining protein annotations (e.g., GO Cellular Compartment and Biological Process, KEGG and Pfam) within each NP corona reveals correlations by 1D-enrichment analysis between protein annotations and NP biophysicochemical properties suggesting specific relationships at the nano-bio surface. Discussion: We have demonstrated the selection and optimization of a panel of 10 NPs for plasma proteome profiling. We have also demonstrated the breadth and depth of this panel's ability to accurately and precisely quantify proteins from plasma. We believe the robustness and scalability of the Proteograph platform could enable population-scale deep and unbiased proteomics analysis previously not feasible using existing workflows. Citation Format: John E. Blume, William C. Manning, Gregory Troiano, Asim Siddiqui, Philip Ma, Robert Langer, Vivek Farias, Omid C. Farokhzad. Analytical validation of the multi-nanoparticle Proteograph platform for rapid and deep proteomic profiling [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2848.

Introduction: Though early detection of NSCLC greatly improves prognosis, we lack useful clinical tests. Genomics approaches utilizing cell-free DNA provide suitable specificity but moderate sensitivity for early cancer detection. Plasma proteins have the potential to deliver robust panels of biomarkers for early cancer detection that may be complimentary to genomics markers. Complex workflows, which enable deep and unbiased interrogation of plasma proteins that span 10 orders of magnitude, have made it impractical to efficiently perform robust studies, and consequently, comprehensive proteomic data vastly lags other “omics”. Herein, we report a multi-NP Proteograph platform that rapidly, reproducibly, deeply, and scalably interrogates proteins from biofluids. In a study of 268 subjects, comparing on average 1779 plasma proteins of NSCLC subjects to healthy and pulmonary co-morbid controls, we identified classification panels comprising proteins with known and unknown roles in NSCLC, offering the promise of new biomarkers for early disease detection. Methods: Subject plasma samples were grouped into NSCLC stages 1,2,3 (early), NSCLC stage 4 (late), or healthy and pulmonary co-morbid controls, for a randomly selected cohort of 288 age- and gender-matched subjects, and interrogated with a panel of NPs in an efficient automated work-flow. Peptides from NP-bound proteins underwent data-independent-acquisition mass spectrometry. Subject samples were also interrogated using conventional Agilent MARS-14 immunodepletion column, which has historically yielded limited clinical value, to determine differences in depth and types protein coverage achieved as compared with panel of NPs. Results: On average 1,779 proteins were detected from each of the 268 subject samples vs. 413 from depleted plasma. The healthy vs early NSCLC random classification after depleted plasma protein removal achieved an average AUC of 0.90. Classification of healthy subjects to late NSCLC had an average AUC of 0.98. Comparison of the top features of the NSCLC classifiers to the co-morbid classifier indicated clinically significant differences. Among the former were proteins with both known and unknown roles in NSCLC (OpenTargets), underscoring the value of unbiased proteomic analysis. Conclusions: We demonstrate the utility of the multi-NP Proteograph platform to deeply profile plasma proteins as novel biomarkers. The performance of the healthy vs. early NSCLC classifier confirms the potential of proteins in early disease detection. Our platform enables deep unbiased plasma protein biomarker profiling that matches genomics workflow throughput and suggests feasibility of parallel large-scale complementary studies of proteins and nucleic acids. Citation Format: John E. Blume, William C. Manning, Gregory Troiano, Asim Siddiqui, Philip Ma, Robert Langer, Vivek Farias, Omid C. Farokhzad. Efficient and scalable profiling of an average of 1779 plasma proteins in 268 subjects with multi-nanoparticle (NP) Proteograph platform enables robust detection of early-stage non-small cell lung cancer (NSCLC) and classification vs. healthy and co-morbid subjects [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr LB-147.

Introduction: Understanding changes in PPI maps from a healthy and diseased state can illuminate our understanding of biological changes and disease processes. PPI maps enable a higher order of information than a simple listing of components by providing functional context, yet existing maps grossly underrepresent the total biological information potential of PPIs. Herein, we describe Proteograph, a novel platform that leverages the nano-bio interactions of nanoparticles (NPs) for deep and unbiased proteomic sampling that can provide insights on PPI across biological samples. Proteograph leverages the protein corona that forms on the surface of NPs as a function of their distinct biophysicochemical properties. NPs reproducibly bind subsets of proteins from biofluids as a function of protein concentration, protein-NP affinity, and protein-protein interactions to form a corona on the NP surface. We have employed Proteograph to quantify known PPIs using a panel of 3 distinct NPs to capture plasma proteins and derive maps of NSCLC and control subjects in order to identify biological changes in interactions, potentially indicative of health and disease. Method and Results: We collected plasma samples from 288 subjects: healthy (n=82), comorbid (n=81) and NSCLC stages I-IV (n=125). In this initial study, we used three NPs with distinct properties and evaluated the protein corona of plasma samples by mass spectrometry (MS) to quantify 1,235 protein groups (1% FDR). A fully automated assay workflow enabled preparation of 3 NPs' corona for MS analysis across 288 subjects in approximately 6 days. We mapped the protein groups to a PPI map derived from the STRING database. Partitioning the network into clusters identified 9 interaction clusters with greater than 10 protein members. These clusters enabled us to investigate differences in the PPI networks between NSCLC patients vs. controls. Evaluating the expression of proteins in these groups, we identified interaction clusters that had significant differences between cancer vs. control (t-test, p < 0.01 Bonferroni corrected). Six of the clusters show differential behavior between NSCLC vs. healthy controls (p < 0.01). Two of these clusters show differential behavior between NSCLC vs. healthy and comorbid (p < 0.01). Investigation of these differentially expressed clusters reveals links to known cancer biology with proteins related to the immune system and endocytosis pathways. Discussion: We have used the Proteograph platform to identify PPI clusters that are differentiated between NSCLC and control individuals. We believe the efficiency of the Proteograph platform applied to sufficiently powered studies may enable comprehensive understanding of known PPIs, and potentially infer and confirm new PPIs, in health and disease. Citation Format: Asim Siddiqui, John E. Blume, William C. Manning, Gregory Troiano, Philip Ma, Robert Langer, Vivek Farias, Omid C. Farokhzad. Plasma protein-protein interactome (PPI) maps derived from the protein corona captured at the nano-bio interface of nanoparticles reveal differential networks for non-small cell lung cancer (NSCLC) and control subjects [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6571.

Purpose Robot-assisted total knee arthroplasty (rTKA) remains in its infancy, is expensive but offers the promise of improved kinematic performance through precise bone cuts, with minimal soft tissue disruption, based on pre-resection soft tissue behaviour. This cadaveric study examined load transfer, soft tissue performance and radiographic indices for conventional (sTKA) versus rTKA. The null hypothesis was there would be no difference between the two modes of implantation. Methods Whole (ten) cadaveric limbs were randomised to receive either robotic (rTKA, N = 5) or conventional measured resection (sTKA, N = 5) knee arthroplasty. Laxity patterns were established using validated fixed sensors (Verasense) with manual maximum displacement for six degrees of freedom. Tibiofemoral load and contact points were determined dynamically using remote sensor technology for medial and lateral compartments through a functional arc of motion (0–110 degrees of motion). Final component position was assessed using pre- and post-implantation CT. Results No significant intergroup differences for laxity were found (n.s.). The rTKA group exhibited consistently balanced mediolateral load throughout the full arc with significantly reduced overall total load across the joint (for distinct points of measurement, p

This is the longest continuous experiment where ethylenediurea (EDU) was used to protect plants from ozone (O3). Effects of long-term ambient O3 exposure (23 ppm h AOT40) on biomass of an O3 sensitive poplar clone (Oxford) were examined after six years from in-ground planting. Trees were irrigated with either water or 450 ppm EDU. Above (-51%) and below-ground biomass (-47%) was reduced by O3 although the effect was significant only for stem and coarse roots. Ambient O3 decreased diameter of the lower stem, and increased moisture content along the stem of not-protected plants (þ16%). No other change in the physical wood structure was observed. A comparison with a previous assessment in the same experiment suggested that O3 effects on biomass partitioning to above-ground organs depend on the tree ontogenetic stage. The root/shoot ratios did not change, suggesting that previous short-term observations of reduced allocation to tree roots may be overestimated.

Four genotypes of snap bean (Phaseolus vulgaris L.) were selected to study the effects of ambient ozone concentration at a cropland area around Beijing by using 450 ppm of ethylenediurea (EDU) as a chemical protectant. During the growing season, the 8 h (9:00–17:00) average ozone concentration was very high, approximately 71.3 ppb, and AOT40 was 29.0 ppm.h. All genotypes showed foliar injury, but ozone-sensitive genotypes exhibited much more injury than ozone-tolerant ones. Compared with control, EDU significantly alleviated foliar injury, increased photosynthesis rate and chlorophyll a fluorescence, Vcmax and Jmax, and seed and pod weights in ozone-sensitive genotypes but not in ozone-tolerant genotypes. EDU did not significantly affect antioxidant contents in any of the genotypes. Therefore, EDU effectively protected sensitive genotypes from ambient ozone damage, while protection on ozone-tolerant genotypes was limited. EDU can be regarded as a useful tool in risk assessment of ambient ozone on food security.

When faced with posterolateral corner (PLC) deficiency, surgeons must choose a total knee replacement (TKR) construct that provides the appropriate level of constraint. This should match the internal constraint of the device to the soft tissue host laxity pattern. Little guidance is available peroperatively, with factors influencing final component choice remaining ill defined. This study aimed to quantify the effect of PLC insufficiency on the "envelope of laxity" (EoL) after TKR and the effect of increasingly component constraint upon knee behavior through a functional arc of flexion. Using computer navigation, mixed effect modeling and loaded cadaveric legs--laxity was quantified under separate states: the native knee, after implantation of a posterior stabilized (PS)-TKR, after sectioning the lateral (fibular) collateral ligament and popliteus tendon (PS-TKR-PLC), and after re-implantation with a semi-constrained "total stabilized" knee replacement (TS-TKR). Laxity was quantified from 0 to 110° of flexion for anterior draw, varus-valgus, and internal-external rotation. Implantation of the PS-TKR was consistently associated with increased constraint when compared to the native knee. PLC sectioning led to significantly increased laxity during varus stress from mid to deep flexion. Revision to a TS-TKR construct restored constraint mimicking that of the primary state but only for the arc of motion 0-90°. In a posterolateral deficient state, a fixed bearing semi-constrained TS-TKR restored the knee to near normal kinematics but this was only achieved from an arc of motion 0-90° of flexion. At higher flexion angles, there remained an unfavorable laxity pattern with varus stress opening.

A two-year experiment exposing Acer truncatum Bunge seedlings to elevated ozone (O3) concentrations above ambient air (AO) and drought stress (DS) was carried out using open-top chambers (OTCs) in a suburb of Beijing in north China in 2012-2013. The results suggested that AO and DS had both significantly reduced leaf mass area (LMA), stomatal conductance (Gs), light saturated photosynthetic rate (Asat) as well as above and below ground biomass at the end of the experiment. It appeared that while drought stress mitigated the expression of foliar injury, LMA, leaf photosynthetic pigments, height growth and basal diameter, due to limited carbon fixation, the O3 - induced reductions in Asat, Gs and total biomass were enhanced 23.7%. 15.5% and 8.1% respectively. These data suggest that when the whole plant was considered that drought under the conditions of this experiment did not protect the Shantung maple seedlings from the effects of O3.

Rising tropospheric ozone concentrations in Asia necessitate the breeding of adapted rice varieties to ensure food security. However, breeding requires field-based evaluation of ample plant material, which can be technically challenging or very costly when using ozone fumigation facilities. The chemical ethylenediurea (EDU) has been proposed for estimating the effects of ozone in large-scale field applications, but controlled experiments investigating constitutive effects on rice or its suitability to detect genotypic differences in ozone tolerance are missing. This study comprised a controlled open top chamber experiment with four treatments (i) control (average ozone concentration 16 ppb), (ii) control with EDU application, (iii) ozone stress (average 77 ppb for 7 h daily throughout the season), and (iv) ozone stress with EDU application. Three contrasting rice genotypes were tested, i.e. the tolerant line L81 and the sensitive Nipponbare and BR28. The ozone treatment had significant negative effects on plant growth (height and tillering), stomatal conductance, SPAD value, spectral reflectance indices such as the normalized difference vegetation index (NDVI), lipid peroxidation, as well as biomass and grain yields. These negative effects were more pronounced in the a priori sensitive varieties, especially the widely grown Bangladeshi variety BR28, which showed grain yield reductions by 37 percent. EDU application had almost no effects on plants in the absence of ozone, but partly mitigated ozone effects on foliar symptoms, lipid peroxidation, SPAD value, stomatal conductance, several spectral reflectance parameters, panicle number, grain yield, and spikelet sterility. EDU responses were more pronounced in sensitive genotypes than in the tolerant L81. In conclusion, EDU had no constitutive effects on rice and partly offset negative ozone effects, especially in sensitive varieties. It can thus be used to diagnose ozone damage in field grown rice and for distinguishing tolerant (less EDU-responsive) and sensitive (more EDU-responsive) genotypes.

No abstract available Keywords: echocardiography; pulmonary hypertension; scurvy; vitamin C.

Purpose and hypothesis Correct femoral component rotation at knee arthroplasty influences patellar tracking and may determine function at extremes of movement. Additionally, such malrotation may deleteriously influence flexion/extension gap geometry and soft tissue balancing kinematics. Little is known about the effect of subtle rotational change upon load transfer across the tibiofemoral articulation. Our null hypothesis was that femoral component rotation would not influence load across this joint in predictable manner. Methods A cadaveric study was performed to examine load transfer using the orthosensor device, respecting laxity patterns in 6° of motion, to examine load across the medial and lateral compartments across a full arc of motion. Mixed-effect modelling allowed for quantification of the effect upon load with internal and external femoral component rotation in relation to a datum in a modern single-radius cruciate-retaining primary knee design. Results No significant change in maximal laxity was found between different femoral rotational states. Internal rotation of the femoral component resulted in significant increase in medial compartment load transfer for knee flexion including and beyond 60°. External rotation of the femoral component within the limits studied did not influence tibiofemoral load transfer. Conclusions Internal rotation of the femoral component will adversely influence medial compartment load transfer and could lead to premature polyethylene wear on the medial side.

Background Tibial component rotation at time of knee arthroplasty can influence conformity, load transmission across the polyethylene surface, and perhaps ultimately determined survivorship. Optimal tibial component rotation on the cut surface is reliant on standard per operative manual stressing. This subjective assessment aims to balance constraint and stability of the articulation through a full arc of movement. Methods Using a cadaveric model, computer navigation and under defined, previously validated loaded conditions mimicking the in vivo setting, the influence of maximal tibial component external rotation compared with the neutral state was examined for changes in laxity and tibiofemoral continuous load using 3D displacement measurement and an orthosensor continuous load sensor implanted within the polyethylene spacer in a simulated single radius total knee arthroplasty. Results No significant difference was found throughout arc of motion (0-115 degrees of flexion) for maximal varus and/or valgus or rotatory laxity between the 2 states. The neutral state achieved equivalence for mediolateral load distribution at each point of flexion. We have found that external rotation of the tibial component increased medial compartment load in comparison with the neutral position. Compared with the neutral state, external rotation consistently effected a marginal, but not significant reduction in lateral load under similar loading conditions. The effects were most pronounced in midflexion. Conclusion On the basis of these findings, we would advocate for the midtibial tubercle point to determine tibial component rotation and caution against component external rotation.

The persistence of high ground-level ozone (O3) concentration in most regions of the northern hemisphere has severe implications to crop production, wild plant conservation, and forest sustainability. Therefore, methods for plant protection against O3 and O3 biomonitoring are of high relevance; however, there is not a method that can be applied in cultivations, which are intended for human consumption. After spraying bean (Phaseolus vulgaris L. cv. Pinto) seedlings with ethylene diurea, olive oil, or myclobutanil and exposing them to O3-enriched air (90 nmol mol−1) for a week (8 h day−1), we found that commercial olive oil can be effectively used as a protectant of plants against O3. This protection is attributed to avoidance of O3 uptake into the mesophyll, via decreased stomatal conductance. Olive oil can be applied even in organic cultivations, either for biomonitoring purposes or for short-term protection of plants during O3 episodes. Further studies are needed in order to investigate potential direct reaction of O3 with olive oil. Yet, attention should be paid when myclobutanil is applied to plants which are used for O3 biomonitoring purposes due to potential confounding effects by increasing O3-caused visible injury to plant leaves.