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We use GRACE-derived terrestrial water storage (TWS) and ERA-interim air temperature, as proxy for available water and temperature constraints on vegetation productivity, inferred from MODIS satellite normalized difference vegetation index (NDVI), in Northern Eurasia during 2002-2011. We investigate how changes in TWS affect the correlation between NDVI and temperature during the non-frozen season. We find that vegetation growth exhibits significant spatial and temporal variability associated with varying trend in TWS and temperature. The largest NDVI gains occur over boreal forests associated with warming and wetting. The largest NDVI losses occur over grasslands in the Southwestern Ob associated with regional drying and cooling, with dominant constraint from TWS. Over grasslands and temperate forests in the Southeast Ob and South Yenisei, wetting and cooling lead to a dominant temperature constraint due to the relaxation of TWS constraints. Overall, we find significant monthly correlation of NDVI with TWS and temperature over 35% and 50% of the domain, respectively. These results indicate that water availability (TWS) plays a major role in modulating Eurasia vegetation response to temperature changes.

The non-frozen (NF) season duration strongly influences the northern carbon cycle where frozen (FR) temperatures are a major constraint to biological processes. The landscape freeze-thaw (FT) signal from satellite microwave remote sensing provides a surrogate measure of FR temperature constraints to ecosystem productivity, trace gas exchange, and surface water mobility. We analysed a new global satellite data record of daily landscape FT dynamics derived from temporal classification of overlapping SMMR and SSM/I 37 GHz frequency brightness temperatures (Tb). The FT record was used to quantify regional patterns, annual variability, and trends in the NF season over northern (≥45°N) vegetated land areas. The ecological significance of these changes was evaluated against satellite normalized difference vegetation index (NDVI) anomalies, estimated moisture and temperature constraints to productivity determined from meteorological reanalysis, and atmospheric CO2 records. The FT record shows a lengthening (2.4 days decade-1; p < 0.005) mean annual NF season trend (1979-2010) for the high northern latitudes that is 26% larger than the Northern Hemisphere trend. The NDVI summer growth response to these changes is spatially complex and coincides with local dominance of cold temperature or moisture constraints to productivity. Longer NF seasons are predominantly enhancing productivity in cold temperature-constrained areas, whereas these effects are reduced or reversed in more moisture-constrained areas. Longer NF seasons also increase the atmospheric CO2 seasonal amplitude by enhancing both regional carbon uptake and emissions. We find that cold temperature constraints to northern growing seasons are relaxing, whereas potential benefits for productivity and carbon sink activity are becoming more dependent on the terrestrial water balance and supply of plant-available moisture needed to meet additional water use demands under a warming climate. © 2014 Taylor & Francis.

We use monthly measurements of time-variable gravity from the GRACE (Gravity Recovery and Climate Experiment) satellite mission to quantify changes in terrestrial water storage (TWS) in the Lena river basin, Eurasia, during the period April 2002 to September 2010. We estimate a TWS increase of 32 10 km 3/yr for the entire basin, equivalent to an increase in water thickness of 1.3 0.4cm/yr over a basin of 2.4 million km2. We compare TWS estimates from GRACE with time series of precipitation (P) minus evapotranspiration (ET) from ERA-Interim reanalysis minus observational river discharge (R). We find an excellent agreement in annual and inter-annual variability between the two time series. Furthermore, we find that a bias of -20 10% in P-ET is sufficient to effectively close the water budget with GRACE. When we account for this bias, the time series of cumulative TWS from GRACE and climatological data agree to within 3.8 cm of water thickness, or 9% of the mean annual P. The TWS increase is not uniform across the river basin and exhibits a peak, over an area of 502,400 km2, centered at 118.5E, 62.5N, and underlain by discontinuous permafrost. In this region, we attribute the observed TWS increase of 68 19 km3 to an increase in subsurface water storage. This large subsurface water signal will have a significant impact on the terrestrial hydrology of the region, including increased baseflow and alteration of seasonal runoff. © 2012 by the American Geophysical Union.

One reason arid and semi-arid environments have been used to store waste is due to low groundwater recharge, presumably limiting the potential for meteoric water to mobilize and transport contaminants into groundwater. The U.S. Department of Energy Office of Legacy Management (LM) is evaluating selected uranium mill tailings disposal cell covers to be managed as evapotranspiration (ET) covers, where vegetation is used to naturally remove water from the cover profile via transpiration, further reducing deep percolation. An important parameter in monitoring the performance of ET covers is soil moisture (SM). If SM is too high, water may drain into tailings material, potentially transporting contaminants into groundwater; if SM is too low, radon flux may increase through the cover. However, monitoring SM via traditional instrumentation is invasive, expensive, and may fail to account for spatial heterogeneity, especially over vegetated disposal cells. Here we investigated the potential for non-invasive SM monitoring using radar remote sensing and other geospatial data to see if this approach could provide a practical, accurate, and spatially comprehensive tool to monitor SM. We used theoretical simulations to analyze the sensitivity of multi-frequency radar backscatter to SM at different depths of a field-scale (3 ha) drainage lysimeter embedded within an in-service LM disposal cell. We then evaluated a shallow and deep form of machine learning (ML) using Google Earth Engine to integrate multi-source observations and estimate the SM profile across six soil layers from depths of 0-2 m. The ML models were trained using in situ SM measurements from 2019 and validated using data from 2014 to 2018 and 2020-2021. Model predictors included backscatter observations from satellite synthetic aperture radar, vegetation, temperature products from optical infrared sensors, and accumulated, gridded rainfall data. The radar simulations confirmed that the lower frequencies (L- and P-band) and smaller incidence angles show better sensitivity to deeper soil layers and an overall larger SM dynamic range relative to the higher frequencies (C- and X-band). The ML models produced accurate SM estimates throughout the soil profile (r values from 0.75 to 0.94; RMSE = 0.003-0.017 cm 3 /cm 3 ; bias = 0.00 cm 3 /cm 3 ), with the simpler shallow-learning approach outperforming a selected deep-learning model. The ML models we developed provide an accurate, cost-effective tool for monitoring SM within ET covers that could be applied to other vegetated disposal cell covers, potentially including those with rock-armored covers., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Bone Marrow Stimulation of osteochondral lesions of the talus has been shown to be a successful way to treat cartilage injuries. Newer data suggest that Bone Marrow Stimulation is best reserved for osteochondral lesions of the talus Sizes Less Than 107.4 mm 2 in area. Additionally, newer smaller and deeper techniques to perform bone marrow stimulation have resulted in less subchondral bone damage, less cancellous compaction, and superior bone marrow access with multiple trabecular access channels. Biologic adjuvants such as platelet-rich plasma (PRP), hyaluronic acid (HA), and bone marrow aspirate concentrate (BMAC) may lead to better functional outcomes when used concomitant to bone marrow stimulation., Competing Interests: Disclosure J.S. Kimball - No Disclosures. R.D. Ferkel - Arthrex, Inc: Other financial or material support; Arthroscopy Association of North America: Board or committee member; Cannuflow: Paid consultant; Geistlich Pharma: Paid consultant; Mitek: Other financial or material support; Sawbones/Pacific Research Laboratories: IP royalties; Smith & Nephew: IP royalties; Other financial or material support; Paid consultantVericel: Paid consultant; Wolters Kluwer Health - Lippincott Williams & Wilkins: Editorial or governing board; Publishing royalties, financial or material support. E.I. Ferkel - AAOS: Board or committee member; American Orthopaedic Foot and Ankle Society: Board or committee member; American Orthopaedic Society for Sports Medicine: Board or committee member; Arthrex, Inc: Paid consultant; Paid presenter or speaker; Arthroscopy Association of North America: Board or committee member; DJ Orthopaedics: Research support; Ferring Pharmaceuticals: Paid consultant; Paid presenter or speaker; Medartis: Paid consultant; Mitek: Paid consultant; Research support; Ossio: Paid consultant; Ossur: Research support; Smith & Nephew: Paid consultant; Research support., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Purpose: To assess the utility of using dynamic ultrasound for postoperative evaluation after superior capsular reconstruction (SCR) by evaluating graft integrity and its correlation with clinical outcomes at a minimum 2-year follow-up., Methods: A retrospective chart review was conducted to identify patients who underwent SCR between July 2015 and July 2020 with a minimum 2-year clinical and ultrasound follow-up. Clinical outcome measures included Simple Shoulder (SS) and American Shoulder and Elbow Surgeon (ASES) scores. Integrity of the SCR graft was evaluated by dynamic ultrasound., Results: We evaluated 22 shoulders in 21 patients with a mean follow-up of 44.8 months (range, 24-71 months). The graft was found to be intact by ultrasound evaluation in 82% (18/22). Patients with intact grafts had higher mean SS (11.6 vs 7.8, P  = .00079) and ASES (91.2 vs 64.1, P  = .0296) scores at latest follow-up compared to those with failed grafts. Those with intact grafts also had significant improvement in SS (3.7 vs 11.6, P < .00001) and ASES (23.2 vs 91.2, P < .00001) scores at latest follow-up compared to their preoperative scores. In contrast, patients with graft failure had no significant improvement in SS (6.3 vs 9.0, P  = .123) and ASES (40.4 vs 58.3, P  = .05469) scores at latest follow-up compared to their preoperative scores. There was no difference between clinical outcomes at 6 to 12 months vs latest follow-up for both SS ( P  = .11, P  = .5) and ASES ( P  = .27, P  = .21) scores., Conclusions: SCR grafts were found by ultrasound to be intact in 82% of cases. Patients with intact grafts on ultrasound had significant improvement in functional outcome scores while those with graft failure did not. Functional outcome scores suggest that maximal recovery from this procedure occurs by 6 to 12 months., Level of Evidence: Level IV, therapeutic case series., Competing Interests: The authors report the following potential conflicts of interest or sources of funding: C.M.J. reports stock or stock options with Sonex outside the submitted work and is a board or committee member of the 10.13039/100013615American Shoulder and Elbow Surgeons. W.P.P. is a paid consultant, speaker, or presenter for 10.13039/100007307Arthrex and is a board or committee member of the 10.13039/100013615American Shoulder and Elbow Surgeons. All other authors (J.S.K., D.W., M.T.G., H.M.S.) declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Full ICMJE author disclosure forms are available for this article online, as supplementary material., (© 2023 The Authors.)

Satellite microwave sensors are well suited for monitoring landscape freeze-thaw (FT) transitions owing to the strong brightness temperature (TB) or backscatter response to changes in liquid water abundance between predominantly frozen and thawed conditions. The FT retrieval is also a sensitive climate indicator with strong biophysical importance. However, retrieval algorithms can have difficulty distinguishing the FT status of soils from that of overlying features such as snow and vegetation, while variable land conditions can also degrade performance. Here, we applied a deep learning model using a multilayer convolutional neural network driven by AMSR2 and SMAP TB records, and trained on surface (~0-5 cm depth) soil temperature FT observations. Soil FT states were classified for the local morning (6 a.m.) and evening (6 p.m.) conditions corresponding to SMAP descending and ascending orbital overpasses, mapped to a 9 km polar grid spanning a five-year (2016-2020) record and Northern Hemisphere domain. Continuous variable estimates of the probability of frozen or thawed conditions were derived using a model cost function optimized against FT observational training data. Model results derived using combined multi-frequency (1.4, 18.7, 36.5 GHz) TBs produced the highest soil FT accuracy over other models derived using only single sensor or single frequency TB inputs. Moreover, SMAP L-band (1.4 GHz) TBs provided enhanced soil FT information and performance gain over model results derived using only AMSR2 TB inputs. The resulting soil FT classification showed favorable and consistent performance against soil FT observations from ERA5 reanalysis (mean percent accuracy, MPA: 92.7%) and in situ weather stations (MPA: 91.0%). The soil FT accuracy was generally consistent between morning and afternoon predictions and across different land covers and seasons. The model also showed better FT accuracy than ERA5 against regional weather station measurements (91.0% vs. 86.1% MPA). However, model confidence was lower in complex terrain where FT spatial heterogeneity was likely beneath the effective model grain size. Our results provide a high level of precision in mapping soil FT dynamics to improve understanding of complex seasonal transitions and their influence on ecological processes and climate feedbacks, with the potential to inform Earth system model predictions., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Donahue, Kimball, Du, Bunt, Colliander, Moghaddam, Johnson, Kim and Rawlins.)

Arctic-boreal landscapes are experiencing profound warming, along with changes in ecosystem moisture status and disturbance from fire. This region is of global importance in terms of carbon feedbacks to climate, yet the sign (sink or source) and magnitude of the Arctic-boreal carbon budget within recent years remains highly uncertain. Here, we provide new estimates of recent (2003-2015) vegetation gross primary productivity (GPP), ecosystem respiration (R eco ), net ecosystem CO 2 exchange (NEE; R eco  - GPP), and terrestrial methane (CH 4 ) emissions for the Arctic-boreal zone using a satellite data-driven process-model for northern ecosystems (TCFM-Arctic), calibrated and evaluated using measurements from >60 tower eddy covariance (EC) sites. We used TCFM-Arctic to obtain daily 1-km 2 flux estimates and annual carbon budgets for the pan-Arctic-boreal region. Across the domain, the model indicated an overall average NEE sink of -850 Tg CO 2 -C year -1 . Eurasian boreal zones, especially those in Siberia, contributed to a majority of the net sink. In contrast, the tundra biome was relatively carbon neutral (ranging from small sink to source). Regional CH 4 emissions from tundra and boreal wetlands (not accounting for aquatic CH 4 ) were estimated at 35 Tg CH 4 -C year -1 . Accounting for additional emissions from open water aquatic bodies and from fire, using available estimates from the literature, reduced the total regional NEE sink by 21% and shifted many far northern tundra landscapes, and some boreal forests, to a net carbon source. This assessment, based on in situ observations and models, improves our understanding of the high-latitude carbon status and also indicates a continued need for integrated site-to-regional assessments to monitor the vulnerability of these ecosystems to climate change., (© 2023 John Wiley & Sons Ltd.)

Long-term atmospheric CO 2 concentration records have suggested a reduction in the positive effect of warming on high-latitude carbon uptake since the 1990s. A variety of mechanisms have been proposed to explain the reduced net carbon sink of northern ecosystems with increased air temperature, including water stress on vegetation and increased respiration over recent decades. However, the lack of consistent long-term carbon flux and in situ soil moisture data has severely limited our ability to identify the mechanisms responsible for the recent reduced carbon sink strength. In this study, we used a record of nearly 100 site-years of eddy covariance data from 11 continuous permafrost tundra sites distributed across the circumpolar Arctic to test the temperature (expressed as growing degree days, GDD) responses of gross primary production (GPP), net ecosystem exchange (NEE), and ecosystem respiration (ER) at different periods of the summer (early, peak, and late summer) including dominant tundra vegetation classes (graminoids and mosses, and shrubs). We further tested GPP, NEE, and ER relationships with soil moisture and vapor pressure deficit to identify potential moisture limitations on plant productivity and net carbon exchange. Our results show a decrease in GPP with rising GDD during the peak summer (July) for both vegetation classes, and a significant relationship between the peak summer GPP and soil moisture after statistically controlling for GDD in a partial correlation analysis. These results suggest that tundra ecosystems might not benefit from increased temperature as much as suggested by several terrestrial biosphere models, if decreased soil moisture limits the peak summer plant productivity, reducing the ability of these ecosystems to sequester carbon during the summer., (© 2022 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

Warming of northern high latitude regions (NHL, > 50 °N) has increased both photosynthesis and respiration which results in considerable uncertainty regarding the net carbon dioxide (CO 2 ) balance of NHL ecosystems. Using estimates constrained from atmospheric observations from 1980 to 2017, we find that the increasing trends of net CO 2 uptake in the early-growing season are of similar magnitude across the tree cover gradient in the NHL. However, the trend of respiratory CO 2 loss during late-growing season increases significantly with increasing tree cover, offsetting a larger fraction of photosynthetic CO 2 uptake, and thus resulting in a slower rate of increasing annual net CO 2 uptake in areas with higher tree cover, especially in central and southern boreal forest regions. The magnitude of this seasonal compensation effect explains the difference in net CO 2 uptake trends along the NHL vegetation- permafrost gradient. Such seasonal compensation dynamics are not captured by dynamic global vegetation models, which simulate weaker respiration control on carbon exchange during the late-growing season, and thus calls into question projections of increasing net CO 2 uptake as high latitude ecosystems respond to warming climate conditions., (© 2022. The Author(s).)

Invasive alien species (IAS) are a rising threat to biodiversity, national security, and regional economies, with impacts in the hundreds of billions of U.S. dollars annually. Proactive or predictive approaches guided by scientific knowledge are essential to keeping pace with growing impacts of invasions under climate change. Although the rapid development of diverse technologies and approaches has produced tools with the potential to greatly accelerate invasion research and management, innovation has far outpaced implementation and coordination. Technological and methodological syntheses are urgently needed to close the growing implementation gap and facilitate interdisciplinary collaboration and synergy among evolving disciplines. A broad review is necessary to demonstrate the utility and relevance of work in diverse fields to generate actionable science for the ongoing invasion crisis. Here, we review such advances in relevant fields including remote sensing, epidemiology, big data analytics, environmental DNA (eDNA) sampling, genomics, and others, and present a generalized framework for distilling existing and emerging data into products for proactive IAS research and management. This integrated workflow provides a pathway for scientists and practitioners in diverse disciplines to contribute to applied invasion biology in a coordinated, synergistic, and scalable manner., (© 2022 Cambridge Philosophical Society. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.)

Earth's ecosystems are increasingly threatened by "hot drought," which occurs when hot air temperatures coincide with precipitation deficits, intensifying the hydrological, physiological, and ecological effects of drought by enhancing evaporative losses of soil moisture (SM) and increasing plant stress due to higher vapor pressure deficit (VPD). Drought-induced reductions in gross primary production (GPP) exert a major influence on the terrestrial carbon sink, but the extent to which hotter and atmospherically drier conditions will amplify the effects of precipitation deficits on Earth's carbon cycle remains largely unknown. During summer and autumn 2020, the U.S. Southwest experienced one of the most intense hot droughts on record, with record-low precipitation and record-high air temperature and VPD across the region. Here, we use this natural experiment to evaluate the effects of hot drought on GPP and further decompose those negative GPP anomalies into their constituent meteorological and hydrological drivers. We found a 122 Tg C (>25%) reduction in GPP below the 2015-2019 mean, by far the lowest regional GPP over the Soil Moisture Active Passive satellite record. Roughly half of the estimated GPP loss was attributable to low SM (likely a combination of record-low precipitation and warming-enhanced evaporative depletion), but record-breaking VPD amplified the reduction of GPP, contributing roughly 40% of the GPP anomaly. Both air temperature and VPD are very likely to continue increasing over the next century, likely leading to more frequent and intense hot droughts and substantially enhancing drought-induced GPP reductions., (© 2022 The Authors. Global Change Biology published by John Wiley & Sons Ltd. This article has been contributed to by US Government employees and their work is in the public domain in the USA.)

Eutrophication is a severe environmental pollution problem for inland waters and poses significant threats to the water safety. Monitoring trophic state of inland waters using optical remote sensing generally requires the inversion of water quality parameters, such as chlorophyll-a, secchi depth, etc. However, the accurate inversion of these individual indicators remains challenging, while the associated retrieval errors can propagate and degrade the evaluation of trophic state. Hence, we proposed a novel monitoring method by developing a Trophic State Index (TSI) based on optical remote-sensing parameters, i.e., Forel-Ule index (FUI) and non-water absorption coefficient at 674 nm (referred to as a t-w (674)) retrieved from Sentinel-3 Ocean and Land Color Instrument (OLCI) imagery. The estimated TSI showed favorable correspondence with observed water quality data, including coefficient of determination (r 2 = 0.91), root mean squared error (RMSE = 5.54), and mean absolute percentage error (MAPE = 10.69%). Using the Sentinel-3 OLCI data, the proposed method also had very good performance in the field spectrum (MAPE = 5.25 % , RMSE = 3.36). The monthly trophic state evaluation also showed congruence (MAPE = 12.51 % , RMSE = 6.41) with surface water quality monthly report (SWQMR) from the Ministry of Environment and Ecology of the People's Republic of China. The monthly TSI showed favorable agreement for 23 ungauged lakes (RMSE = 7.26, MAPE = 12.78%), indicating potential utility for regional lake water quality monitoring. The proposed method was then applied to 47 other large (>50 km 2 ) water bodies in the Middle-and-Lower watershed of Yangtze River and the Huaihe watershed to evaluate the spatial and temporal variation of trophic state from 2016 to 2020. The TSI results revealed several lakes, such as Lake Honghu and Lake Luoma, with rapidly deteriorating water quality during the study period, while other lakes show relative improvement (e.g., Xiashan Reservoir), indicating unbalanced environmental pressure over the region. Overall, this study showed promising performance and potential for satellite-based monitoring of regional aquatic environments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Arctic warming is affecting snow cover and soil hydrology, with consequences for carbon sequestration in tundra ecosystems. The scarcity of observations in the Arctic has limited our understanding of the impact of covarying environmental drivers on the carbon balance of tundra ecosystems. In this study, we address some of these uncertainties through a novel record of 119 site-years of summer data from eddy covariance towers representing dominant tundra vegetation types located on continuous permafrost in the Arctic. Here we found that earlier snowmelt was associated with more tundra net CO 2 sequestration and higher gross primary productivity (GPP) only in June and July, but with lower net carbon sequestration and lower GPP in August. Although higher evapotranspiration (ET) can result in soil drying with the progression of the summer, we did not find significantly lower soil moisture with earlier snowmelt, nor evidence that water stress affected GPP in the late growing season. Our results suggest that the expected increased CO 2 sequestration arising from Arctic warming and the associated increase in growing season length may not materialize if tundra ecosystems are not able to continue sequestering CO 2 later in the season., (© 2022. The Author(s).)

Drought is one of the most ecologically and economically devastating natural phenomena affecting the United States, causing the U.S. economy billions of dollars in damage, and driving widespread degradation of ecosystem health. Many drought indices are implemented to monitor the current extent and status of drought so stakeholders such as farmers and local governments can appropriately respond. Methods to forecast drought conditions weeks to months in advance are less common but would provide a more effective early warning system to enhance drought response, mitigation, and adaptation planning. To resolve this issue, we introduce DroughtCast, a machine learning framework for forecasting the United States Drought Monitor (USDM). DroughtCast operates on the knowledge that recent anomalies in hydrology and meteorology drive future changes in drought conditions. We use simulated meteorology and satellite observed soil moisture as inputs into a recurrent neural network to accurately forecast the USDM between 1 and 12 weeks into the future. Our analysis shows that precipitation, soil moisture, and temperature are the most important input variables when forecasting future drought conditions. Additionally, a case study of the 2017 Northern Plains Flash Drought shows that DroughtCast was able to forecast a very extreme drought event up to 12 weeks before its onset. Given the favorable forecasting skill of the model, DroughtCast may provide a promising tool for land managers and local governments in preparing for and mitigating the effects of drought., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Brust, Kimball, Maneta, Jencso and Reichle.)

Importance: Rotator cuff pathology is a growing concern in the ageing population. If cement augmentation of suture anchors improves pullout strength, its application can potentially be applied in cases of poor bone quality to prevent anchor failure., Objective: To evaluate the biomechanical benefits and fixation strength of cement-augmented versus non-augmented suture anchors in the proximal humerus during rotator cuff repair (RCR)., Evidence Review: A systematic review of PubMed, Embase and Cochrane Library was performed to identify all published articles reporting on biomechanical analysis of suture anchors in the shoulder in a cadaveric model. Inclusion criteria required fresh-frozen specimens, placement in the footprint of the proximal humerus, and comparative assessment of fixation constructs with or without polymethylmethacrylate (PMMA) or bioabsorbable composite cement augmentation. Biomechanical testing procedure, cement augmentation method and pullout force were assessed., Findings: After review of 105 abstracts, seven full manuscripts met inclusion criteria. Six of seven studies reported statistically significant differences in mean pullout force between augmented (three PMMAs, three composites, one PMMA vs composite) and non-augmented anchors. Of two studies evaluating cycles to failure, both found a significant increase in the augmented versus non-augmented anchors. Of two studies stratifying by anchor position, both investigations identified significant differences in mean pullout strength between augmented and non-augmented anchors at the posteromedial and anterolateral anchor positions., Conclusions and Relevance: Cement augmentation of suture anchors in cadaveric humeri for RCR improves pullout strength regardless of cement type used or anchor position. Cement augmentation may provide a viable option for future clinical application., Level of Evidence: IV, systematic review., Competing Interests: Competing interests: Other others maintain the following competing interests: JL: paid presenter; JC and SLS: board membership and paid consultant; NHA: paid consultant, presenter and royalty/stock option; BRW: board membership, paid consultant and stock options., (© International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Biological invasions are accelerating worldwide, causing major ecological and economic impacts in aquatic ecosystems. The urgent decision-making needs of invasive species managers can be better met by the integration of biodiversity big data with large-domain models and data-driven products. Remotely sensed data products can be combined with existing invasive species occurrence data via machine learning models to provide the proactive spatial risk analysis necessary for implementing coordinated and agile management paradigms across large scales. We present a workflow that generates rapid spatial risk assessments on aquatic invasive species using occurrence data, spatially explicit environmental data, and an ensemble approach to species distribution modeling using five machine learning algorithms. For proof of concept and validation, we tested this workflow using extensive spatial and temporal hybridization and occurrence data from a well-studied, ongoing, and climate-driven species invasion in the upper Flathead River system in northwestern Montana, USA. Rainbow Trout (RBT; Oncorhynchus mykiss ), an introduced species in the Flathead River basin, compete and readily hybridize with native Westslope Cutthroat Trout (WCT; O. clarkii lewisii ), and the spread of RBT individuals and their alleles has been tracked for decades. We used remotely sensed and other geospatial data as key environmental predictors for projecting resultant habitat suitability to geographic space. The ensemble modeling technique yielded high accuracy predictions relative to 30-fold cross-validated datasets (87% 30-fold cross-validated accuracy score). Both top predictors and model performance relative to these predictors matched current understanding of the drivers of RBT invasion and habitat suitability, indicating that temperature is a major factor influencing the spread of invasive RBT and hybridization with native WCT. The congruence between more time-consuming modeling approaches and our rapid machine-learning approach suggest that this workflow could be applied more broadly to provide data-driven management information for early detection of potential invaders., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Carter, van Rees, Hand, Muhlfeld, Luikart and Kimball.)

➤: Oxidative stress has been implicated as a causative factor in many disease states, possibly including the diminished bone mineral density in osteoporosis., ➤: Understanding the effects of oxidative stress on the development of osteoporosis may lead to further research improving preventative and therapeutic measures that can combat this important contributor to morbidity and mortality worldwide., ➤: A diet rich in whole plant foods with high antioxidant content along with antioxidant-preserving lifestyle changes may improve bone mineral density and reduce the risk of fragility-related fractures. While it is not explicitly clear if antioxidant activity is the effector of this change, the current evidence supports this possibility., ➤: Supplementation with isolated antioxidants may also provide some osteoprotective benefits, but whole plant food-derived antioxidants potentially have more overall benefits. Larger-scale clinical trials are needed to give credence to definitive clinical recommendations., Competing Interests: Disclosure: The authors indicated that no external funding was received for any aspect of this work. The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJS/G503)., (Copyright © 2021 by The Journal of Bone and Joint Surgery, Incorporated.)

●Plants are characterized by the iso/anisohydry continuum depending on how they regulate leaf water potential (Ψ L ). However, how iso/anisohydry changes over time in response to year-to-year variations in environmental dryness and how such responses vary across different regions remains poorly characterized. ●We investigated how dryness, represented by aridity index, affects the interannual variability of ecosystem iso/anisohydry at the regional scale, estimated using satellite microwave vegetation optical depth (VOD) observations. This ecosystem-level analysis was further complemented with published field observations of species-level Ψ L . ●We found different behaviors in the directionality and sensitivity of isohydricity (σ) with respect to the interannual variation of dryness in different ecosystems. These behaviors can largely be differentiated by the average dryness of the ecosystem itself: in mesic ecosystems, σ decreases in drier years with a higher sensitivity to dryness; in xeric ecosystems, σ increases in drier years with a lower sensitivity to dryness. These results were supported by the species-level synthesis. ●Our study suggests that how plants adjust their water use across years - as revealed by their interannual variability in isohydricity - depends on the dryness of plants' living environment. This finding advances our understanding of plant responses to drought at regional scales., (© 2020 The Authors New Phytologist © 2020 New Phytologist Trust.)

Background: Posterior malleolus fractures are traditionally managed with open reduction and internal fixation or percutaneous anterior-to-posterior screws. We present a third option using a percutaneous technique for the placement of posterior-to-anterior-directed screws. An anatomic safety analysis is done using cadaveric specimens., Methods: Using 15 embalmed specimens (10 F and 5 M), a guidewire was placed using the described technique. The posterolateral ankle was dissected to evaluate for damage to vulnerable structures including the sural nerve, peroneal artery, and flexor hallucis longus/flexor digitorum longus/peroneal/Achilles tendons. The distance from the sural nerve and peroneal artery was measured to the guidewire at its nearest point. The tendons were evaluated for traumatic piercings., Results: The sural nerve had a mean distance to wire of 5.3 mm (range 0 to 12) and the peroneal artery had a mean distance to wire of 5.7 mm (range 2 to 13 mm) with no traumatic piercings of either structure. The flexor hallucis longus/flexor digitorum longus/peroneal/Achilles tendons had no traumatic piercings., Conclusion: This percutaneous technique provides a safe alternative to the standard open and traditional percutaneous techniques. It has limited application and is suitable for noncomminuted minimally displaced posterior malleolus fractures and those with fragile tissues where the morbidity of the soft tissue exposure outweighs the benefit of an open reduction., (Copyright © 2021 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Orthopaedic Surgeons.)

Accurate monitoring of crop condition is critical to detect anomalies that may threaten the economic viability of agriculture and to understand how crops respond to climatic variability. Retrievals of soil moisture and vegetation information from satellite-based remote-sensing products offer an opportunity for continuous and affordable crop condition monitoring. This study compared weekly anomalies in accumulated gross primary production (GPP) from the SMAP Level-4 Carbon (L4C) product to anomalies calculated from a state-scale weekly crop condition index (CCI) and also to crop yield anomalies calculated from county-level yield data reported at the end of the season. We focused on barley, spring wheat, corn, and soybeans cultivated in the continental United States from 2000 to 2018. We found that consistencies between SMAP L4C GPP anomalies and both crop condition and yield anomalies increased as crops developed from the emergence stage (r: 0.4-0.7) and matured (r: 0.6-0.9) and that the agreement was better in drier regions (r: 0.4-0.9) than in wetter regions (r: -0.8-0.4). The L4C provides weekly GPP estimates at a 1-km scale, permitting the evaluation and tracking of anomalies in crop status at higher spatial detail than metrics based on the state-level CCI or county-level crop yields. We demonstrate that the L4C GPP product can be used operationally to monitor crop condition with the potential to become an important tool to inform decision-making and research., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Wurster, Maneta, Kimball, Endsley and Beguería.)

The capability and synergistic use of multisource satellite observations for flood monitoring and forecasts is crucial for improving disaster preparedness and mitigation. Here, surface fractional water cover (FW) retrievals derived from Soil Moisture Active Passive (SMAP) L-band (1.4 GHz) brightness temperatures were used for flood assessment over southeast Africa during the Cyclone Idai event. We then focused on five subcatchments of the Pungwe basin and developed a machine learning based approach with the support of Google Earth Engine for daily (24-h) forecasting of FW and 30-m inundation downscaling and mapping. The Classification and Regression Trees model was selected and trained using retrievals derived from SMAP and Landsat coupled with rainfall forecasts from the NOAA Global Forecast System. Independent validation showed that FW predictions over randomly selected dates are highly correlated ( R = 0.87) with the Landsat observations. The forecast results captured the flood temporal dynamics from the Idai event; and the associated 30-m downscaling results showed inundation spatial patterns consistent with independent satellite synthetic aperture radar observations. The data-driven approach provides new capacity for flood monitoring and forecasts leveraging synergistic satellite observations and big data analysis, which is particularly valuable for data sparse regions.

Arctic river discharge increased over the last several decades, conveying heat and freshwater into the Arctic Ocean and likely affecting regional sea ice and the ocean heat budget. However, until now, there have been only limited assessments of riverine heat impacts. Here, we adopted a synthesis of a pan-Arctic sea ice-ocean model and a land surface model to quantify impacts of river heat on the Arctic sea ice and ocean heat budget. We show that river heat contributed up to 10% of the regional sea ice reduction over the Arctic shelves from 1980 to 2015. Particularly notable, this effect occurs as earlier sea ice breakup in late spring and early summer. The increasing ice-free area in the shelf seas results in a warmer ocean in summer, enhancing ocean-atmosphere energy exchange and atmospheric warming. Our findings suggest that a positive river heat-sea ice feedback nearly doubles the river heat effect., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)

Arctic and boreal ecosystems play an important role in the global carbon (C) budget, and whether they act as a future net C sink or source depends on climate and environmental change. Here, we used complementary in situ measurements, model simulations, and satellite observations to investigate the net carbon dioxide (CO 2 ) seasonal cycle and its climatic and environmental controls across Alaska and northwestern Canada during the anomalously warm winter to spring conditions of 2015 and 2016 (relative to 2010-2014). In the warm spring, we found that photosynthesis was enhanced more than respiration, leading to greater CO 2 uptake. However, photosynthetic enhancement from spring warming was partially offset by greater ecosystem respiration during the preceding anomalously warm winter, resulting in nearly neutral effects on the annual net CO 2 balance. Eddy covariance CO 2 flux measurements showed that air temperature has a primary influence on net CO 2 exchange in winter and spring, while soil moisture has a primary control on net CO 2 exchange in the fall. The net CO 2 exchange was generally more moisture limited in the boreal region than in the Arctic tundra. Our analysis indicates complex seasonal interactions of underlying C cycle processes in response to changing climate and hydrology that may not manifest in changes in net annual CO 2 exchange. Therefore, a better understanding of the seasonal response of C cycle processes may provide important insights for predicting future carbon-climate feedbacks and their consequences on atmospheric CO 2 dynamics in the northern high latitudes., (© 2019 John Wiley & Sons Ltd.)

A method to assess global land surface water ( fw ) inundation dynamics was developed by exploiting the enhanced fw sensitivity of L-band (1.4 GHz) passive microwave observations from the Soil Moisture Active Passive (SMAP) mission. The L-band fw ( fw LBand ) retrievals were derived using SMAP H-polarization brightness temperature ( T b ) observations and predefined L-band reference microwave emissivities for water and land endmembers. Potential soil moisture and vegetation contributions to the microwave signal were represented from overlapping higher frequency T b observations from AMSR2. The resulting fw LBand global record has high temporal sampling (1-3 days) and 36-km spatial resolution. The fw LBand annual averages corresponded favourably ( R =0.85, p-value <0.001) with a 250-m resolution static global water map (MOD44W) aggregated at the same spatial scale, while capturing significant inundation variations worldwide. The monthly fw LBand averages also showed seasonal inundation changes consistent with river discharge records within six major US river basins. An uncertainty analysis indicated generally reliable fw LBand performance for major land cover areas and under low to moderate vegetation cover, but with lower accuracy for detecting water bodies covered by dense vegetation. Finer resolution (30-m) fw LBand results were obtained for three sub-regions in North America using an empirical downscaling approach and ancillary global Water Occurrence Dataset (WOD) derived from the historical Landsat record. The resulting 30-m fw LBand retrievals showed favourable spatial accuracy for water (commission error 31.46%, omission error 30.20%) and land (commission error 0.87%, omission error 0.96%) classifications and seasonal wet and dry periods when compared to independent water maps derived from Landsat-8 imagery. The new fw LBand algorithms and continuing SMAP and AMSR2 operations provide for near real-time, multi-scale monitoring of global surface water inundation dynamics and potential flood risk.

Plant traits are both responsive to local climate and strong predictors of primary productivity. We hypothesized that future climate change might promote a shift in global plant traits resulting in changes in Gross Primary Productivity (GPP). We characterized the relationship between key plant traits, namely Specific Leaf Area (SLA), height, and seed mass, and local climate and primary productivity. We found that by 2070, tropical and arid ecosystems will be more suitable for plants with relatively lower canopy height, SLA and seed mass, while far northern latitudes will favor woody and taller plants than at present. Using a network of tower eddy covariance CO2 flux measurements and the extrapolated plant trait maps, we estimated the global distribution of annual GPP under current and projected future plant community distribution. We predict that annual GPP in northern biomes (≥45 °N) will increase by 31% (+8.1 ± 0.5 Pg C), but this will be offset by a 17.9% GPP decline in the tropics (-11.8 ± 0.84 Pg C). These findings suggest that regional climate changes will affect plant trait distributions, which may in turn affect global productivity patterns.

Near-surface atmospheric Vapor Pressure Deficit (VPD) is a key environmental variable affecting vegetation water stress, evapotranspiration, and atmospheric moisture demand. Although VPD is readily derived from in situ standard weather station measurements, more spatially continuous global observations for regional monitoring of VPD are lacking. Here, we document a new method to estimate daily (both a.m. and p.m.) global land surface VPD at a 25-km resolution using a satellite passive microwave remotely sensed Land Parameter Data Record (LPDR) derived from the Advanced Microwave Scanning Radiometer (AMSR) sensors. The AMSR-derived VPD record shows strong correspondence (correlation coefficient ≥ 0.80, p -value < 0.001) and overall good performance (0.48 kPa ≤ Root Mean Square Error ≤ 0.69 kPa) against independent VPD observations from the Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2) data. The estimated AMSR VPD retrieval uncertainties vary with land cover type, satellite observation time, and underlying LPDR data quality. These results provide new satellite capabilities for global mapping and monitoring of land surface VPD dynamics from ongoing AMSR2 operations. Overall good accuracy and similar observations from both AMSR2 and AMSR-E allow for the development of climate data records documenting recent (from 2002) VPD trends and potential impacts on vegetation, land surface evaporation, and energy budgets., Competing Interests: Conflicts of Interest: The authors declare no conflict of interest. The founding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results.

An important feature of the Arctic is large spatial heterogeneity in active layer conditions, which is generally poorly represented by global models and can lead to large uncertainties in predicting regional ecosystem responses and climate feedbacks. In this study, we developed a spatially integrated modelling and analysis framework combining field observations, local scale (~ 50 m resolution) active layer thickness (ALT) and soil moisture maps derived from airborne low frequency (L+P-band) radar measurements, and global satellite environmental observations to investigate the ALT sensitivity to recent climate trends and landscape heterogeneity in Alaska. Modelled ALT results show good correspondence with in situ measurements in higher permafrost probability (PP ≥ 70%) areas (n = 33, R = 0.60, mean bias = 1.58 cm, RMSE = 20.32 cm), but with larger uncertainty in sporadic and discontinuous permafrost areas. The model results also reveal widespread ALT deepening since 2001, with smaller ALT increases in northern Alaska (mean trend = 0.32 ± 1.18 cm yr -1 ) and much larger increases (> 3 cm yr -1 ) across interior and southern Alaska. The positive ALT trend coincides with regional warming and a longer snow-free season (R = 0.60 ± 0.32). A spatially integrated analysis of the radar retrievals and model sensitivity simulations demonstrated that uncertainty in the spatial and vertical distribution of soil organic carbon (SOC) was the largest factor affecting modeled ALT accuracy, while soil moisture played a secondary role. Potential improvements in characterizing SOC heterogeneity, including better spatial sampling of soil conditions and advances in remote sensing of SOC and soil moisture, will enable more accurate predictions of active layer conditions and refinement of the modelling framework across a larger domain., Competing Interests: Competing interests. The authors declare no conflict of interest.

The Soil Moisture Active Passive (SMAP) mission Level-4 Soil Moisture (L4&#95;SM) product provides 3-hourly, 9-km resolution, global estimates of surface (0-5 cm) and root-zone (0-100 cm) soil moisture and related land surface variables from 31 March 2015 to present with ~2.5day latency. The ensemble-based L4&#95;SM algorithm assimilates SMAP brightness temperature (Tb) observations into the Catchment land surface model. This study describes the spatially distributed L4&#95;SM analysis and assesses the observation-minus-forecast (O-F) Tb residuals and the soil moisture and temperature analysis increments. Owing to the climatological rescaling of the Tb observations prior to assimilation, the analysis is essentially unbiased, with global mean values of ~0.37 K for the O-F Tb residuals and practically zero for the soil moisture and temperature increments. There are, however, modest regional (absolute) biases in the O-F residuals (under ~3 K), the soil moisture increments (under ~0.01 m 3 m -3 ), and the surface soil temperature increments (under ~1 K). Typical instantaneous values are ~6 K for O-F residuals, ~0.01 (~0.003) m 3 m -3 for surface (root-zone) soil moisture increments, and ~0.6 K for surface soil temperature increments. The O-F diagnostics indicate that the actual errors in the system are overestimated in deserts and densely vegetated regions and underestimated in agricultural regions and transition zones between dry and wet climates. The O-F auto-correlations suggest that the SMAP observations are used efficiently in western North America, the Sahel, and Australia, but not in many forested regions and the high northern latitudes. A case study in Australia demonstrates that assimilating SMAP observations successfully corrects short-term errors in the L4&#95;SM rainfall forcing.

Background Context: A paucity of data exists studying outcomes of patients with syringomyelia undergoing spinal deformity correction. The literature does not stratify patients by syrinx size, which is likely a major contributor to outcomes., Purpose: The study aimed to compare differences in outcomes between patients with large (≥4 mm) and small syrinxes (<4 mm) undergoing spinal deformity correction., Design: This is a retrospective review., Patient Sample: The sample included 28 patients (11 with large syrinx [LS, >4 mm] and 17 with small syrinx [SS, <4 mm])., Outcome Measures: The outcome measures were radiographic, operative, and neurophysiological measures., Methods: We retrospectively reviewed 28 patients with syringomyelia who underwent spine deformity surgery with 2-year follow-up. Demographic, surgical, and radiographic data were collected and compared preoperatively and at 2 years., Results: The LS group (11 patients) trended toward more left-sided thoracic curves (36% vs. 18%, p=.38) and was more likely to have had a Chiari decompression (45% vs. 12%, p=.08). The LS patients had larger preoperative major curves (LS=66° vs. SS=57°, p=.05), more thoracic kyphosis (LS=42°, SS=24°, p<.01), and greater rib prominences (LS=16°, SS=13°, p=.04). The LS patients had more levels fused (LS=12.2, SS=11.2, p=.05), higher estimated blood loss (EBL) (LS=1068 cc, SS=832 cc, p=.04), and a trend toward less percent correction of the major curve (LS=57%, SS=65%, p=.18). Four of 11 LS patients (36%) did not have somatosensory evoked potentials, and one of these also did not have motor evoked potentials. Neuromonitoring changes occurred in 3 of 11 (27%) LS patients and in none of the SS patients, with no postoperative deficits., Conclusions: Outcomes of patients with syringomyelia undergoing spine deformity surgery are dependent on the size of the syrinx. Those with large syringomyelia are fused longer with more EBL and less correction. Spine surgeons should be aware that these patients are more likely to have less reliable neuromonitoring, with a higher chance of experiencing a change., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Understanding how environmental variation influences population genetic structure is important for conservation management because it can reveal how human stressors influence population connectivity, genetic diversity and persistence. We used riverscape genetics modelling to assess whether climatic and habitat variables were related to neutral and adaptive patterns of genetic differentiation (population-specific and pairwise FST ) within five metapopulations (79 populations, 4583 individuals) of steelhead trout (Oncorhynchus mykiss) in the Columbia River Basin, USA. Using 151 putatively neutral and 29 candidate adaptive SNP loci, we found that climate-related variables (winter precipitation, summer maximum temperature, winter highest 5% flow events and summer mean flow) best explained neutral and adaptive patterns of genetic differentiation within metapopulations, suggesting that climatic variation likely influences both demography (neutral variation) and local adaptation (adaptive variation). However, we did not observe consistent relationships between climate variables and FST across all metapopulations, underscoring the need for replication when extrapolating results from one scale to another (e.g. basin-wide to the metapopulation scale). Sensitivity analysis (leave-one-population-out) revealed consistent relationships between climate variables and FST within three metapopulations; however, these patterns were not consistent in two metapopulations likely due to small sample sizes (N = 10). These results provide correlative evidence that climatic variation has shaped the genetic structure of steelhead populations and highlight the need for replication and sensitivity analyses in land and riverscape genetics., (© 2015 John Wiley & Sons Ltd.)

Species distribution modeling has been widely used in studying habitat relationships and for conservation purposes. However, neglecting ecological knowledge about species, e.g. their seasonal movements, and ignoring the proper environmental factors that can explain key elements for species survival (shelter, food and water) increase model uncertainty. This study exemplifies how these ecological gaps in species distribution modeling can be addressed by modeling the distribution of the emu (Dromaius novaehollandiae) in Australia. Emus cover a large area during the austral winter. However, their habitat shrinks during the summer months. We show evidence of emu summer habitat shrinkage due to higher fire frequency, and low water and food availability in northern regions. Our findings indicate that emus prefer areas with higher vegetation productivity and low fire recurrence, while their distribution is linked to an optimal intermediate (~0.12 m3 m(-3)) soil moisture range. We propose that the application of three geospatial data products derived from satellite remote sensing, namely fire frequency, ecosystem productivity, and soil water content, provides an effective representation of emu general habitat requirements, and substantially improves species distribution modeling and representation of the species' ecological habitat niche across Australia.

Arctic terrestrial ecosystems are major global sources of methane (CH4); hence, it is important to understand the seasonal and climatic controls on CH4 emissions from these systems. Here, we report year-round CH4 emissions from Alaskan Arctic tundra eddy flux sites and regional fluxes derived from aircraft data. We find that emissions during the cold season (September to May) account for ≥ 50% of the annual CH4 flux, with the highest emissions from noninundated upland tundra. A major fraction of cold season emissions occur during the "zero curtain" period, when subsurface soil temperatures are poised near 0 °C. The zero curtain may persist longer than the growing season, and CH4 emissions are enhanced when the duration is extended by a deep thawed layer as can occur with thick snow cover. Regional scale fluxes of CH4 derived from aircraft data demonstrate the large spatial extent of late season CH4 emissions. Scaled to the circumpolar Arctic, cold season fluxes from tundra total 12 ± 5 (95% confidence interval) Tg CH4 y(-1), ∼ 25% of global emissions from extratropical wetlands, or ∼ 6% of total global wetland methane emissions. The dominance of late-season emissions, sensitivity to soil environmental conditions, and importance of dry tundra are not currently simulated in most global climate models. Because Arctic warming disproportionally impacts the cold season, our results suggest that higher cold-season CH4 emissions will result from observed and predicted increases in snow thickness, active layer depth, and soil temperature, representing important positive feedbacks on climate warming.

Recent studies showed that anomalous dry conditions and limited moisture supply roughly between 1998 and 2008, especially in the Southern Hemisphere, led to reduced vegetation productivity and ceased growth in land evapotranspiration (ET). However, natural variability of Earth's climate system can degrade capabilities for identifying climate trends. Here we produced a long-term (1982-2013) remote sensing based land ET record and investigated multidecadal changes in global ET and underlying causes. The ET record shows a significant upward global trend of 0.88 mm yr(-2) (P < 0.001) over the 32-year period, mainly driven by vegetation greening (0.018% per year; P < 0.001) and rising atmosphere moisture demand (0.75 mm yr(-2); P = 0.016). Our results indicate that reduced ET growth between 1998 and 2008 was an episodic phenomenon, with subsequent recovery of the ET growth rate after 2008. Terrestrial precipitation also shows a positive trend of 0.66 mm yr(-2) (P = 0.08) over the same period consistent with expected water cycle intensification, but this trend is lower than coincident increases in evaporative demand and ET, implying a possibility of cumulative water supply constraint to ET. Continuation of these trends will likely exacerbate regional drought-induced disturbances, especially during regional dry climate phases associated with strong El Niño events.

Purpose: This retrospective chart review evaluates the clinical and radiographic outcomes of anterior vertebral body tethering (VBT) at 1-year follow-up. Anterior VBT offers a fusionless treatment option for skeletally immature patients with adolescent idiopathic scoliosis. It is a growth-modulation technique, which utilizes patients' growth to attain progressive scoliosis correction. Numerous animal models support its promise; however, clinical data remain sparse., Methods: Clinical and radiographic data were retrospectively analyzed. We reviewed 32 patients who underwent thoracic VBT with a minimum one-year follow-up. Pertinent clinical and radiographic data were collected. ANOVA, Student's t test and Fisher's exact test were utilized to compare different time points., Results: 32 patients with thoracic idiopathic scoliosis (72 % female) with a minimum one-year follow-up were identified; mean age at surgery was 12 years. All patients were considered skeletally immature pre-operatively; mean Risser score 0.42, mean Sanders score 3.2. Patients underwent tethering of an average of 7.7 levels (range 7-11). Median blood loss was 100 cc. The mean pre-operative thoracic curve magnitude was 42.8° ± 8.0° which corrected to 21.0° ± 8.5° on first erect and 17.9° ± 11.4° at most recent. The pre-operative lumbar curve of 25.2° ± 7.3° demonstrated progressive correction (first erect = 18.0° ± 7.1°, 1 year = 12.6° ± 9.4°, p < 0.00001). Thoracic axial rotation measured 13.4° pre-operatively and 7.4° at the most recent measurement (p < 0.00001). One patient experienced prolonged atelectasis which required a bronchoscopy; otherwise, no major complications were observed., Conclusions: Our early results indicate that anterior VBT is a safe and potentially effective treatment option for skeletally immature patients with idiopathic scoliosis. These patients experienced an improvement of their scoliosis with minimal major complications. However, longer term follow-up of this cohort will reveal the true benefits of this promising technique., Level of Evidence: IV.

Object: Almost all pediatric patients who incur a spinal cord injury (SCI) will develop scoliosis, and younger patients are at highest risk for curve progression requiring surgical intervention. Although the use of pedicle screws is increasing in popularity, their impact on SCI-related scoliosis has not been described. The authors retrospectively reviewed the radiographic outcomes of pedicle screw-only constructs in all patients who had undergone SCI-related scoliosis correction at a single institution., Methods: Medical records and radiographs from Shriner's Hospital for Children-Philadelphia for the period between November 2004 and February 2011 were retrospectively reviewed., Results: Thirty-seven patients, whose mean age at the index surgery was 14.91±3.29 years, were identified. The cohort had a mean follow-up of 33.2±22.8 months. The mean preoperative coronal Cobb angle was 65.5°±25.7°, which corrected to 20.3°±14.4°, translating into a 69% correction (p<0.05). The preoperative coronal balance was 24.4±22.6 mm, with a postoperative measurement of 21.6±20.7 mm (p=1.00). Preoperative pelvic obliquity was 12.7°±8.7°, which corrected to 4.1°±3.8°, translating into a 68% correction (p<0.05). Preoperative shoulder balance, as measured by the clavicle angle, was 8.2°±8.4°, which corrected to 2.7°±3.1° (67% correction, p<0.05). Preoperatively, thoracic kyphosis measured 44.2°±23.7° and was 33.8°±11.5° postoperatively. Thoracolumbar kyphosis was 18.7°±12.1° preoperatively, reduced to 8.1°±7.7° postoperatively, and measured 26.8°±20.2° at the last follow-up (p<0.05). Preoperatively, lumbar lordosis was 35.3°±22.0°, which remained stable at 35.6°±15.0° postoperatively., Conclusions: Pedicle screw constructs appear to provide better correction of coronal parameters than historically reported and provide significant improvement of sagittal kyphosis as well. Although pedicle screws appear to provide good radiographic results, correlation with clinical outcomes is necessary to determine the true impact of pedicle screw constructs on SCI-related scoliosis correction.

Study Design: Retrospective review., Objective: To report the 2-year results of the initial cohort undergoing anterior vertebral body tethering (VBT)., Summary of Background Data: Anterior VBT is a promising new technique with abundant preclinical studies but very few clinical results. It is a growth modulation technique, which utilizes patients' growth to attain progressive correction of their scoliosis. We report 2-year results of the initial cohort undergoing this procedure., Methods: After obtaining institutional review board approval, we retrospectively reviewed our first 11 consecutive patients who underwent anterior VBT with 2-year follow-up. We collected pertinent preoperative, intraoperative, and most recent clinical and radiographical data. Student t test and Fisher exact test were utilized to compare different time points., Results: Eleven patients with thoracic idiopathic scoliosis (8 females) were identified, with a mean age of 12.3 ± 1.6 years. Preoperatively, all were skeletally immature (Sanders mean = 3.4 ± 1.1; Risser mean = 0.6 ± 1.1). All underwent tethering of an average of 7.8 ± 0.9 (range: 7-9) levels, with the most proximal being T5 and the most distal L2. Preoperative thoracic Cobb angle averaged 44.2 ± 9.0° and corrected to 20.3 ± 11.0° on first erect, with progressive improvement at 2 years (Cobb angle = 13.5 ± 11.6°, % correction = 70%; P < 0.00002). Similarly, the preoperative lumbar curve of 25.1 ± 8.7° demonstrated progressive correction (first erect = 14.9 ± 4.9°, 2 yr = 7.2 ± 5.1°, % correction = 71%; P < 0.0002). Thoracic axial rotation as measured by a scoliometer went from 12.4 ± 3.3° preoperatively to 6.9 ± 3.4° at the most recent measurement (P < 0.01). No major complications were observed. As anticipated, 2 patients returned to the operating room at 2 years postoperatively for loosening of the tether to prevent overcorrection., Conclusion: Anterior VBT is a promising technique for skeletally immature patients with idiopathic scoliosis. This technique can be performed safely and can result in progressive correction., Level of Evidence: 4.

The land surface phenology (LSP) start of season (SOS) metric signals the seasonal onset of vegetation activity, including canopy growth and associated increases in land-atmosphere water, energy and carbon (CO2) exchanges influencing weather and climate variability. The vegetation optical depth (VOD) parameter determined from satellite passive microwave remote sensing provides for global LSP monitoring that is sensitive to changes in vegetation canopy water content and biomass, and insensitive to atmosphere and solar illumination constraints. Direct field measures of canopy water content and biomass changes desired for LSP validation are generally lacking due to the prohibitive costs of maintaining regional monitoring networks. Alternatively, a normalized microwave reflectance index (NMRI) derived from GPS base station measurements is sensitive to daily vegetation water content changes and may provide for effective microwave LSP validation. We compared multiyear (2007-2011) NMRI and satellite VOD records at over 300 GPS sites in North America, and their derived SOS metrics for a subset of 24 homogenous land cover sites to investigate VOD and NMRI correspondence, and potential NMRI utility for LSP validation. Significant correlations (P<0.05) were found at 276 of 305 sites (90.5 %), with generally favorable correspondence in the resulting SOS metrics (r (2)=0.73, P<0.001, RMSE=36.8 days). This study is the first attempt to compare satellite microwave LSP metrics to a GPS network derived reflectance index and highlights both the utility and limitations of the NMRI data for LSP validation, including spatial scale discrepancies between local NMRI measurements and relatively coarse satellite VOD retrievals.

Object: Several studies of the outcomes of patients with adolescent idiopathic scoliosis (AIS) with thoracolumbar and lumbar curves after treatment with posterior pedicle screws have been reported, but most of these studies reported only 2-year follow-up. The authors analyzed the radiographic and clinical outcomes of patients with thoracolumbar and lumbar curves treated with posterior pedicle screws after 5 years of follow-up., Methods: A multicenter database was retrospectively queried to identify patients with AIS who underwent spinal fusion for Lenke 3C, 5C, and 6C curves. Radiographs from the following times were compared: preoperative, first follow-up visit, 1-year follow-up visit, 2-year follow-up visit, and 5-year follow-up visit. Chart review included scoliometer measurements, Scoliosis Research Society (SRS)-22 questionnaires, and complications requiring return to the operating room., Results: Among 26 patients with Lenke 3C, 5C, and 6C curves, the mean (± SD) age was 14.6 ± 2.1 years. From the time of the preoperative radiographs to the 5-year follow-up radiographs, there was a statistically significant improvement in the mean coronal lumbar Cobb angles (p < 0.0001), and from the time of the first postoperative radiographs to the 5-year follow-up radiographs, the lumbar curve remained stable (p = 0.14). From the time of the preoperative radiographs to the 5-year follow-up radiographs, there was a statistically significant improvement in the mean coronal thoracic Cobb angles (p < 0.0001), and from the time of the first postoperative radiographs to the 5-year follow-up radiographs, the thoracic curve remained stable (p = 0.10). From the first postoperative visit to the 5-year follow-up visit, the thoracic kyphosis (T5-12) remained stable (p = 0.10), and from the time of the preoperative radiographs to the 5-year follow-up radiographs, the lumbar lordosis (T-12 to top of sacrum) remained stable (p = 0.44). From the preoperative visit to the 5-year follow-up visit, the coronal balance improved significantly (p < 0.05) and remained stable from the first postoperative visit to the 5-year follow-up visit (p = 0.20). The SRS-22 total scores improved significantly from before surgery to 5 years after surgery (p < 0.0001). No patients required reoperation because of complications., Conclusions: Correction of the coronal, sagittal, and axial planes in this cohort of patients was maintained from the first follow-up measurements to 5 years after surgery. In addition, at 5 years after surgery total SRS-22 scores and inclinometer readings were improved from preoperative scores and measurements.

The rate of vegetation recovery from boreal wildfire influences terrestrial carbon cycle processes and climate feedbacks by affecting the surface energy budget and land-atmosphere carbon exchange. Previous forest recovery assessments using satellite optical-infrared normalized difference vegetation index (NDVI) and tower CO(2) eddy covariance techniques indicate rapid vegetation recovery within 5-10 years, but these techniques are not directly sensitive to changes in vegetation biomass. Alternatively, the vegetation optical depth (VOD) parameter from satellite passive microwave remote sensing can detect changes in canopy biomass structure and may provide a useful metric of post-fire vegetation response to inform regional recovery assessments. We analyzed a multi-year (2003-2010) satellite VOD record from the NASA AMSR-E (Advanced Microwave Scanning Radiometer for EOS) sensor to estimate forest recovery trajectories for 14 large boreal fires from 2004 in Alaska and Canada. The VOD record indicated initial post-fire canopy biomass recovery within 3-7 years, lagging NDVI recovery by 1-5 years. The VOD lag was attributed to slower non-photosynthetic (woody) and photosynthetic (foliar) canopy biomass recovery, relative to the faster canopy greenness response indicated from the NDVI. The duration of VOD recovery to pre-burn conditions was also directly proportional (P < 0.01) to satellite (moderate resolution imaging spectroradiometer) estimated tree cover loss used as a metric of fire severity. Our results indicate that vegetation biomass recovery from boreal fire disturbance is generally slower than reported from previous assessments based solely on satellite optical-infrared remote sensing, while the VOD parameter enables more comprehensive assessments of boreal forest recovery., (© 2013 John Wiley & Sons Ltd.)

Environmental variability has important influences on mosquito life cycles and understanding the spatial and temporal patterns of mosquito populations is critical for mosquito control and vector-borne disease prevention. Meteorological data used for model-based predictions of mosquito abundance and life cycle dynamics are typically acquired from ground-based weather stations; however, data availability and completeness are often limited by sparse networks and resource availability. In contrast, environmental measurements from satellite remote sensing are more spatially continuous and can be retrieved automatically. This study compared environmental measurements from the NASA Advanced Microwave Scanning Radiometer on EOS (AMSR-E) and in situ weather station data to examine their ability to predict the abundance of two important mosquito species (Aedes vexans and Culex tarsalis) in Sioux Falls, South Dakota, USA from 2005 to 2010. The AMSR-E land parameters included daily surface water inundation fraction, surface air temperature, soil moisture, and microwave vegetation opacity. The AMSR-E derived models had better fits and higher forecasting accuracy than models based on weather station data despite the relatively coarse (25-km) spatial resolution of the satellite data. In the AMSR-E models, air temperature and surface water fraction were the best predictors of Aedes vexans, whereas air temperature and vegetation opacity were the best predictors of Cx. tarsalis abundance. The models were used to extrapolate spatial, seasonal, and interannual patterns of climatic suitability for mosquitoes across eastern South Dakota. Our findings demonstrate that environmental metrics derived from satellite passive microwave radiometry are suitable for predicting mosquito population dynamics and can potentially improve the effectiveness of mosquito-borne disease early warning systems.

Object: The thoracic rib hump, caused by axial rotation of the spine, is one of the most dissatisfying cosmetic features associated with adolescent idiopathic scoliosis (AIS). However, advances in instrumentation and surgical techniques, such as direct vertebral body derotation (DVBD), have allowed improved correction in the axial plane and the rib hump. In cases of thoracolumbar/lumbar curves (Lenke Type 5), the lumbar prominence can be equally disfiguring and is often associated with waist asymmetry, another cosmetic concern. Although DVBD has been evaluated in the thoracic spine, little is known about its impact on the lumbar spine. The authors investigated the outcomes of DVBD on the lumbar prominence., Methods: A prospectively collected multicenter database was queried for pediatric patients with AIS and Lenke Type 5 curves. All patients who underwent thoracoplasty procedures were excluded. A total of 34 patients underwent surgical correction via a posterior-only approach using pedicle screw constructs. Nineteen patients underwent concurrent DVBD, and the remaining 15 patients served as a control group and did not undergo DVBD. All patients had a minimum of 2 years of follow-up., Results: The mean age of the entire cohort was 14.9 ± 2.3 years, and the majority of patients were female (88%). All patients had Lenke Type 5C curves with a mean major curve of 46.0° ± 8.7°, which corrected to 13.7° ± 7.2° (70% correction). A mean of 10.7 ± 3.0 levels were fused. Only thoracic kyphosis was significantly different between the groups preoperatively. Similarly, postoperative radiographic parameters were comparable between the groups, with equivalent percentages of correction. Although improvement in the thoracic rib hump was comparable between the groups, the DVBD group had 56.2% correction of the lumbar prominence, and the control group had 76% improvement (p = 0.05)., Conclusions: Although DVBD has been a valuable tool in the management of AIS, the authors' results suggest that its application for thoracolumbar curves may be limited. Further analysis with a larger cohort is required to better ascertain the impact of DVBD on thoracolumbar curves.

Object: Pedicle screw fixation has been theorized to provide better correction of scoliotic deformity, but controversy over the benefits of pedicle screw-only constructs remains, and the longer-term impact of pedicle screw fixation as compared with hybrid constructs is unclear. In this study, a retrospective review of a prospectively collected database was conducted to determine the longer-term impact of pedicle screw fixation as compared with hybrid constructs in patients with adolescent idiopathic scoliosis (AIS)., Methods: The authors retrospectively reviewed a multicenter database of pediatric patients (ages ≤ 18) from 1995 to 2006 and identified 127 patients with Lenke Type 1-4 AIS curves with a minimum 5 years of follow-up. Patients were divided into 2 cohorts based on whether they had undergone pedicle screw fixation or fixation with hybrid constructs., Results: The mean main thoracic curvature of 56.1° ± 13.0°, which corrected to 14.9° ± 9.3°, translated into a mean correction of 73% (p < 0.01). The curve was 19.4° ± 10.6° at 2-year follow-up and 20.5° ± 10.4° at 5 years. When comparing preoperative parameters between the groups, differences were noted in the magnitude of the main thoracic curve (p = 0.04), flexibility of the main thoracic curve (p = 0.02), coronal balance (p = 0.04), T2-12 kyphosis (p = 0.02), and sex (p = 0.02). The pedicle screw cohort had fewer spinal segments instrumented (p < 0.01), fewer anterior releases performed (p = 0.02), and fewer thoracoplasties performed (p < 0.01). By 5 years of follow-up, significant differences were apparent between the two cohorts with respect to upper thoracic curvature (p = 0.01), T2-12 (p = 0.02) and T5-12 (p = 0.02) kyphosis, lumbar lordosis (p < 0.01), and sagittal balance (p = 0.01)., Conclusions: Although some preoperative differences did exist, outcomes were comparable between hybrid and screw constructs at 2 and 5 years. However, hybrid constructs required more concurrent anterior releases and thoracoplasties to achieve similar results.

Floodplains are among the world's most threatened ecosystems due to the pervasiveness of dams, levee systems, and other modifications to rivers. Few unaltered floodplains remain where we may examine their dynamics over decadal time scales. Our study provides a detailed examination of landscape change over a 60-year period (1945-2004) on the Nyack floodplain of the Middle Fork of the Flathead River, a free-flowing, gravel-bed river in northwest Montana, USA. We used historical aerial photographs and airborne and satellite imagery to delineate habitats (i.e., mature forest, regenerative forest, water, cobble) within the floodplain. We related changes in the distribution and size of these habitats to hydrologic disturbance and regional climate. Results show a relationship between changes in floodplain habitats and annual flood magnitude, as well as between hydrology and the cooling and warming phases of the Pacific Decadal Oscillation (PDO). Large magnitude floods and greater frequency of moderate floods were associated with the cooling phases of the PDO, resulting in a floodplain environment dominated by extensive restructuring and regeneration of floodplain habitats. Conversely, warming phases of the PDO corresponded with decreases in magnitude, duration, and frequency of critical flows, creating a floodplain environment dominated by late successional vegetation and low levels of physical restructuring. Over the 60-year time series, habitat change was widespread throughout the floodplain, though the relative abundances of the habitats did not change greatly. We conclude that the long- and short-term interactions of climate, floods, and plant succession produce a shifting habitat mosaic that is a fundamental attribute of natural floodplain ecosystems.

We used a terrestrial ecosystem process model, BIOME-BGC, to investigate historical climate change and fire disturbance effects on regional carbon and water budgets within a 357,500 km(2) portion of the Canadian boreal forest. Historical patterns of increasing atmospheric CO2, climate change, and regional fire activity were used as model drivers to evaluate the relative effects of these impacts to spatial patterns and temporal trends in forest net primary production (NPP) and evapotranspiration (ET). Historical trends of increasing atmospheric CO2 resulted in overall 13% and 5% increases in annual NPP and ET from 1994 to 1996, respectively. NPP was found to be relatively sensitive to changes in air temperature (T(a)), while ET was more sensitive to precipitation (P) change within the ranges of observed climate variability (e.g., +/-2 degrees C for T(a) and +/-20% for P). In addition, the potential effect of climate change related warming on NPP is exacerbated or offset depending on whether these changes are accompanied by respective decreases or increases in precipitation. Historical fire activity generally resulted in reductions of both NPP and ET, which consumed an average of approximately 6% of annual NPP from 1959 to 1996. Areas currently occupied by dry conifer forests were found to be subject to more frequent fire activity, which consumed approximately 8% of annual NPP. The results of this study show that the North American boreal ecosystem is sensitive to historical patterns of increasing atmospheric CO2, climate change and regional fire activity. The relative impacts of these disturbances on NPP and ET interact in complex ways and are spatially variable depending on regional land cover and climate gradients.

The large magnitude of predicted warming at high latitudes and the potential feedback of ecosystems to atmospheric CO 2 concentrations make it important to quantify both warming and its effects on high-latitude carbon balance. We analysed long-term, daily surface meteorological records for 13 sites in Alaska and north-western Canada and an 82-y record of river ice breakup date for the Tanana River in interior Alaska. We found increases in winter and spring temperature extrema for all sites, with the greatest increases in spring minimum temperature, average 0.47 °C per 10 y, and a 0.7-day per 10 y advance in ice breakup on the Tanana River. We used the climate records to drive an ecosystem process model, BIOME&#95;BGC, to simulate the effects of climate change on the carbon and water balances of boreal forest ecosystems. The growing season has lengthened by an average of 2.6 days per 10 y with an advance in average leaf onset date of 1.10 days per 10 y. This advance in the start of the active growing season correlates positively with progressively earlier ice breakup on the Tanana River in interior Alaska. The advance in the start of the growing season resulted in a 20% increase in net primary production for both aspen (Populus tremuloides) and white spruce (Picea glauca) stands. Aspen had a greater mean increase in maintenance respiration than spruce, whereas spruce had a greater mean increase in evapotranspiration. Average decomposition rates also increased for both species. Both net primary production and decomposition are enhanced in our simulations, suggesting that productive forest types may not experience a significant shift in net carbon flux as a result of climate warming.