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Phenology is an integrative science that comprises the study of recurring biological activities or events. In an era of rapidly changing climate, the relationship between the timing of those events and environmental cues such as temperature, snowmelt, water availability, or day length are of particular interest. This article provides an overview of the observer-based plant phenology sampling conducted by the U.S. National Ecological Observatory Network (NEON), the resulting data, and the rationale behind the design. Trained technicians will conduct regular in situ observations of plant phenology at all terrestrial NEON sites for the 30-yr life of the observatory. Standardized and coordinated data across the network of sites can be used to quantify the direction and magnitude of the relationships between phenology and environmental forcings, as well as the degree to which these relationships vary among sites, among species, among phenophases, and through time. Vegetation at NEON sites will also be monitored with tower-based cameras, satellite remote sensing, and annual high-resolution airborne remote sensing. Ground-based measurements can be used to calibrate and improve satellite-derived phenometrics. NEON's phenology monitoring design is complementary to existing phenology research efforts and citizen science initiatives throughout the world and will produce interoperable data. By collocating plant phenology observations with a suite of additional meteorological, biophysical, and ecological measurements (e.g., climate, carbon flux, plant productivity, population dynamics of consumers) at 47 terrestrial sites, the NEON design will enable continental-scale inference about the status, trends, causes, and ecological consequences of phenological change.

Background: The availability of portable and wearable electrocardiographic (ECG) devices has increased secondary to technological development. Single-lead ECG recordings have been shown to reliably detect and characterize cardiac rhythms such as atrial fibrillation. Acquisition of precordial electrodes for full 12-lead ECG reconstruction from bipolar recordings is complicated by the absence of a body ground/Wilson central terminal electrode. The extent of difference between standard precordial leads and those from a wearable bipolar ECG recorder has not been characterized., Objective: The purpose of this study was to characterize the precordial ECG lead set from sequential bipolar recordings from an ECG ring wearable device., Methods: In 70 patients who wore an ECG device on a right-hand finger, sequential precordial leads (CR1-CR6) were obtained along with chest electrodes (V1-V6). During acquisition of the modified precordial lead CR6, a full standardized 12-lead ECG capture was obtained. Signal quality was assessed using automated analysis software, and correlation values between the ring-derived ECG precordial leads and standard ECG leads were compared with regard to QRS duration, QT width, and RR interval., Results: High concordance in the morphologies of precordial ECG leads obtained in a standard fashion and those recorded through an ECG ring was observed. Morphologic alignment improved with increasing laterality of the precordial lead with chest to right arm ring recording (CR5, CR6) compared with anterior chest leads to right arm (CR1, CR2). Segmental measurements of QRS duration and QT segment were well aligned and of high correlation., Conclusion: Wearable ring-based ECG technology is capable of high-fidelity recordings of precordial leads for nonsimultaneous reconstruction of complete ECG sets. These recordings correlate highly with surface-obtained QRS and QT duration measurements and have significant implications for clinical applications. Uninterpretable tracings were primarily due to electrode noise from poor electrode contact., (© 2023 Heart Rhythm Society.)

Recently nitrogen-hydrogen compounds have successfully been applied as co-catalysts for mild conditions ammonia synthesis. Ca 2 NH was shown to act as a H 2 sink during reaction, with H atoms from its lattice being incorporated into the NH 3 (g) product. Thus the ionic transport and diffusion properties of the N-H co-catalyst are fundamentally important to understanding and developing such syntheses. Here we show hydride ion conduction in these materials. Two distinct calcium nitride-hydride Ca 2 NH phases, prepared via different synthetic paths are found to show dramatically different properties. One phase (β) shows fast hydride ionic conduction properties (0.08 S/cm at 600 °C), on a par with the best binary ionic hydrides and 10 times higher than CaH 2 , whilst the other (α) is 100 times less conductive. An in situ combined analysis techniques reveals that the effective β-phase conducts ions via a vacancy-mediated phenomenon in which the charge carrier concentration is dependent on the ion concentration in the secondary site and by extension the vacancy concentration in the main site., (© 2023. The Author(s).)

Historically, relying on plot-level inventories impeded our ability to quantify large-scale change in plant biomass, a key indicator of conservation practice outcomes in rangeland systems. Recent technological advances enable assessment at scales appropriate to inform management by providing spatially comprehensive estimates of productivity that are partitioned by plant functional group across all contiguous US rangelands. We partnered with the Sage Grouse and Lesser Prairie-Chicken Initiatives and the Nebraska Natural Legacy Project to demonstrate the ability of these new datasets to quantify multi-scale changes and heterogeneity in plant biomass following mechanical tree removal, prescribed fire, and prescribed grazing. In Oregon's sagebrush steppe, for example, juniper tree removal resulted in a 21% increase in one pasture's productivity and an 18% decline in another. In Nebraska's Loess Canyons, perennial grass productivity initially declined 80% at sites invaded by trees that were prescriptively burned, but then fully recovered post-fire, representing a 492% increase from nadir. In Kansas' Shortgrass Prairie, plant biomass increased 4-fold (966,809 kg/ha) in pastures that were prescriptively grazed, with gains highly dependent upon precipitation as evidenced by sensitivity of remotely sensed estimates (SD ± 951,308 kg/ha). Our results emphasize that next-generation remote sensing datasets empower land managers to move beyond simplistic control versus treatment study designs to explore nuances in plant biomass in unprecedented ways. The products of new remote sensing technologies also accelerate adaptive management and help communicate wildlife and livestock forage benefits from management to diverse stakeholders., 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 The US Geological Survey, The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: Thyroid gland malignancies are rare in pediatric patients (0.7% of tumors); only 1.8% are observed in patients aged <20 years, with a higher prevalence recorded in women and adolescents. Risk factors include genetic syndromes, MEN disorders, autoimmune diseases, and exposure to ionizing radiation. Radiotherapy is also associated with an increased risk of secondary thyroid cancer. This study describes the clinical features and surgical outcomes of primary and secondary thyroid tumors in pediatric patients., Methods: Institutional data were collected from eight international surgical oncology centers for pediatric patients with thyroid cancer between 2000 and 2020. Statistical analyses were performed using the GraphPad Prism software., Results: Among 255 total cases of thyroid cancer, only 13 (5.1%) were secondary tumors. Primary thyroid malignancies were more likely to be multifocal in origin (odds ratio [OR] 1.993, 95% confidence interval [CI].7466-5.132, p = 0.2323), have bilateral glandular location (OR 2.847, 95% CI.6835-12.68, p = 0.2648), and be metastatic at first diagnosis (OR 1.259, 95% CI.3267-5.696, p > 0.999). Secondary tumors showed a higher incidence of disease relapse (OR 1.556, 95% CI.4579-5.57, p = 0.4525) and surgical complications (OR 2.042, 95% CI 0.7917-5.221, p = 0.1614), including hypoparathyroidism and recurrent laryngeal nerve injury. The overall survival (OS) was 99% at 1 year and 97% after 10 years. No EFS differences were evident between the primary and secondary tumors (chi-square 0.7307, p = 0.39026)., Conclusions: This multicenter study demonstrated excellent survival in pediatric thyroid malignancies. Secondary tumors exhibited greater disease relapse (15.8 vs. 10.5%) and a higher incidence of surgical complications (36.8 vs. 22.2%)., (Copyright © 2022 Martucci, Crocoli, De Pasquale, Spinelli, Strambi, Brazzarola, Morelli, Cassiani, Mancera, Luengas, Lobos, Liberto, Astori, Sarnacki, Couloigner, Simon, Lambert, Abib, Cervantes, Caran, Delgado Lindman, Jones, Shukla, Losty and Inserra.)

In this era of global environmental change and rapid regime shifts, managing core areas that species require to survive and persist is a grand challenge for conservation. Wildlife monitoring data are often limited or local in scale. The emerging ability to map and track spatial regimes (i.e., the spatial manifestation of state transitions) using advanced geospatial vegetation data has the potential to provide earlier warnings of habitat loss because many species of conservation concern strongly avoid spatial regime boundaries. Using 23 yr of data for the lek locations of Greater Prairie-Chicken (Tympanuchus cupido; GPC) in a remnant grassland ecosystem, we demonstrate how mapping changes in the boundaries between grassland and woodland spatial regimes provide a spatially explicit early warning signal for habitat loss for an iconic and vulnerable grassland-obligate known to be highly sensitive to woody plant encroachment. We tested whether a newly proposed metric for the quantification of spatial regimes captured well-known responses of GPC to woody plant expansion into grasslands. Resource selection functions showed that the grass:woody spatial regime boundary strength explained the probability of 80% of relative lek occurrence, and GPC strongly avoided grass:woody spatial regime boundaries at broad scales. Both findings are consistent with well-known expectations derived from GPC ecology. These results provide strong evidence for vegetation-derived delineations of spatial regimes to serve as generalized signals of early warning for state transitions that have major consequences to biodiversity conservation. Mapping spatial regime boundaries over time provided interpretable early warnings of habitat loss. Woody plant regimes displaced grassland regimes starting from the edges of the study area and constricting inward. Correspondingly, the relative probability of lek occurrence constricted in space. Similarly, the temporal trajectory of spatial regime boundary strength increased over time and moved closer to the observed limit of GPC lek site usage relative to grass:woody boundary strength. These novel spatial metrics allow managers to rapidly screen for early warning signals of spatial regime shifts and adapt management practices to defend and grow habitat cores at broad scales., (© 2021 by the Ecological Society of America.)

The use of simultaneous neutron powder diffraction (NPD) and microwave characterisation can provide more information than the use of either technique individually; for example, it enables the differentiation of physisorbed and metal-coordinated species. Many possible experiments using these combined techniques can benefit from the addition of a heat source for sample heating, such as real-time measurements of solvent removal, or chemical and catalytic reactions. This paper documents the design of equipment to conduct simultaneous NPD and 2.5 GHz microwave cavity resonance techniques at elevated temperatures and confirms the use of this equipment for successful desolvation of a metal-organic framework (MOF) sample at 150 °C. The high sensitivity of microwave characterisation of lossy and polar materials is demonstrated at levels much lower than those that can be detected using crystallographic techniques.

Background: To determine if birth-weight (BW) influences primary surgical management of newborns undergoing operation for esophageal atresia and tracheo-esophageal fistula (EA-TEF)., Methods: Newborns undergoing repair of esophageal atresia at a single specialist centre between 1999 and 2017 were categorised into three groups based on BW; Group A < 1.5 kg, Group B <2.5 kg and Group C >2.5 kg. Outcome data analysed were (i) technical ability of the surgeon to perform primary esophageal anastomosis, (ii) anastomotic leak, (iii) anastomotic stricture, (iv) esophageal replacement, (v) need for other procedures notably fundoplication, aortopexy, tracheostomy and (vi) mortality. Statistical analysis was performed using a two-tailed Fisher's exact test and logistic regression., Results: 198 patients underwent surgery for EA-TEF during the study period, Group A (n = 13), Group B (n = 73) and Group C (n = 112). Inability to perform a primary anastomosis was significantly higher in Group A vs Group B (p = 0.003) and Group C (p = 0.004). Birthweight was a significant variable in the ability to perform a primary esophageal anastomosis (OR 1.009, p = 0.004). Mortality rate was significantly higher in Group A vs Group C (P = 0.0158)., Conclusions: Very low birth weight infants are less likely to achieve a definitive primary anastomosis during emergent repair of esophageal atresia, and have a higher mortality., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

We report the heterolysis of molecular hydrogen under ambient conditions by the crystalline frustrated Lewis pair (FLP) 1-{2-[bis(pentafluorophenyl)boryl]phenyl}-2,2,6,6-tetramethylpiperidine (KCAT). The gas-solid reaction provides an approach to prepare the solvent-free, polycrystalline ion pair KCATH2 through a single crystal to single crystal transformation. The crystal lattice of KCATH2 increases in size relative to the parent KCAT by approximately 2%. Microscopy was used to follow the transformation of the highly colored red/orange KCAT to the colorless KCATH2 over a period of 2 h at 300 K under a flow of H 2 gas. There is no evidence of crystal decrepitation during hydrogen uptake. Inelastic neutron scattering employed over a temperature range from 4-200 K did not provide evidence for the formation of polarized H 2 in a precursor complex within the crystal at low temperatures and high pressures. However, at 300 K, the INS spectrum of KCAT transformed to the INS spectrum of KCATH2. Calculations suggest that the driving force is more favorable in the solid state compared to the solution or gas phase, but the addition of H 2 into the KCAT crystal is unfavorable. Ab Initio methods were used to calculate the INS spectra of KCAT, KCATH2, and a possible precursor complex of H 2 in the pocket between the B and N of crystalline KCAT. Ex-situ NMR showed that the transformation from KCAT to KCATH2 is quantitative and our results suggest that the hydrogen heterolysis process occurs via H 2 diffusion into the FLP crystal with a rate-limiting movement of H 2 from inactive positions to reactive sites.

Conservationists are increasingly convinced that coproduction of science enhances its utility in policy, decision-making, and practice. Concomitant is a renewed reliance on privately owned working lands to sustain nature and people. We propose a coupling of these emerging trends as a better recipe for conservation. To illustrate this, we present five elements of coproduction, contrast how they differ from traditional approaches, and describe the role of scientists in successful partnerships. Readers will find coproduction more demanding than the loading dock approach to science delivery but will also find greater rewards, relevance, and impact. Because coproduction is novel and examples of it are rare, we draw on our roles as scientists within the US Department of Agriculture-led Sage Grouse Initiative, North America's largest effort to conserve the sagebrush ecosystem. As coproduction and working lands evolve, traditional approaches will be replaced in order to more holistically meet the needs of nature and people., (© The Author(s) 2019. Published by Oxford University Press on behalf of the American Institute of Biological Sciences.)

Rangelands cover 40-50% of the Earth's terrestrial surface. While often characterized by limited, yet variable resource availability, rangelands are vital for humans, providing numerous ecosystem goods and services. In the conterminous United States (CONUS), the dominant component of rangeland conservation is a network of public rangelands, concentrated in the west. Public rangelands are interspersed with private and tribal rangelands resulting in a complex mosaic of land tenure and management priorities. We quantify ownership patterns of rangeland production at multiple scales across CONUS and find that both total production and average productivity of private rangelands is more than twice that of public and tribal rangelands. At finer scales, private rangelands are consistently more productive than their public counterparts. We also demonstrate an inverse relationship between public rangeland acreage and productivity. While conserving acreage is crucial to rangeland conservation, just as critical are broad-scale ecological patterns and processes that sustain ecosystem services. Across CONUS, ownership regimes capture distinct elements of these patterns and services, demonstrated through disparate production dynamics. As ownership determines the range of feasible conservation actions, and the technical and financial resources available to implement them, understanding ownership-production dynamics is critical for effective and sustained conservation of rangeland ecosystem services., (© 2019 The Authors. Ecological Applications published by Wiley Periodicals, Inc. on behalf of Ecological Society of America.)

New concepts have emerged in theoretical ecology with the intent to quantify complexities in ecological change that are unaccounted for in state-and-transition models and to provide applied ecologists with statistical early warning metrics able to predict and prevent state transitions. With its rich history of furthering ecological theory and its robust and broad-scale monitoring frameworks, the rangeland discipline is poised to empirically assess these newly proposed ideas while also serving as early adopters of novel statistical metrics that provide advanced warning of a pending shift to an alternative ecological regime. Were view multivariate early warning and regime shift detection metrics, identify situations where various metrics will be most useful for rangeland science, and then highlight known shortcomings. Our review of a suite of multivariate-based regime shift/early warning indicators provides a broad range of metrics applicable to a wide variety of data types or contexts, from situations where a great deal is known about the key system drivers and a regime shift is hypothesized a priori, to situations where the key drivers and the possibility of a regime shift are both unknown. These metrics can be used to answer ecological state-and-transition questions, inform policymakers, and provide quantitative decision-making tools for managers.

Essential Biodiversity Variables (EBVs) allow observation and reporting of global biodiversity change, but a detailed framework for the empirical derivation of specific EBVs has yet to be developed. Here, we re-examine and refine the previous candidate set of species traits EBVs and show how traits related to phenology, morphology, reproduction, physiology and movement can contribute to EBV operationalization. The selected EBVs express intra-specific trait variation and allow monitoring of how organisms respond to global change. We evaluate the societal relevance of species traits EBVs for policy targets and demonstrate how open, interoperable and machine-readable trait data enable the building of EBV data products. We outline collection methods, meta(data) standardization, reproducible workflows, semantic tools and licence requirements for producing species traits EBVs. An operationalization is critical for assessing progress towards biodiversity conservation and sustainable development goals and has wide implications for data-intensive science in ecology, biogeography, conservation and Earth observation.

Ammonia absorption has been investigated in metal-organic frameworks (UiO-67, HKUST-1 and CPO-27-Co) using custom-built apparatus that allows simultaneous neutron powder diffraction (NPD), microwave dielectric characterisation and out-gas mass spectroscopy of solid-state materials during ammonia adsorption. Deuterated ammonia was flowed through the sample and absorption monitored using mass flow meters and mass spectroscopy. Argon gas was then flowed through the ammoniated sample to cause ammonia desorption. Changes in structure found from NPD measurements were compared to changes in dielectric characteristics to differentiate physisorbed and metal-coordinated ammonia, as well as determine decomposition of sample materials. The results of these studies allow the identification of materials with useful ammonia storage properties and provides a new metric for the measurement of gas absorption within mesoporous solids.

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.

Aim of Study: The aim of this study was to evaluate management of children with an anterior midline neck swelling by establishing 1) whether a preoperative ultrasound scan (USS) was appropriately requested, performed and reported; 2) whether there was preoperative infection; 3) whether a Sistrunk procedure was performed; 4) the rate of thyroglossal duct cyst (TGDC) recurrence following simple excision vs. Sistrunk procedure., Methods: A single centre retrospective study of children who underwent surgery for anterior midline neck swelling between April 2000 and May 2015 at our institution was performed. These were identified using a clinical coding system, and data were collected from electronic medical records, radiology, and histopathology reports. Recurrence rates between simple excision and Sistrunk groups were compared using Chi-square test., Main Results: 227 patients were identified (115 male, 112 female). 169 (74%) had a preoperative USS. The presence of a thyroid gland was stated in 79% of USS reports. This increased to 92% when the requesting surgeon had specifically asked about this. 48 (21%) patients underwent simple excision, while 175 (77%) had a Sistrunk procedure. Recurrence was significantly more likely following simple excision than a Sistrunk procedure (29% vs 6.9%; P<0.0001). Of 25 TGDC recurrences, 9 (36%) had an inconclusive or alternative histopathological diagnosis at first operation., Conclusion: Preoperative USS should be performed in all patients with an anterior midline neck swelling. Appropriate requesting increases likelihood of a report confirming (or otherwise) the presence of a thyroid gland. A Sistrunk procedure is the operation of choice in all children presenting with an anterior midline neck swelling. The surgeon cannot reliably differentiate a TGDC from alternative pathology intraoperatively., Level of Evidence: Treatment study: level IV., (Copyright © 2017. Published by Elsevier Inc.)

Aim of the Study: To assess the safety and effectiveness of fluoroscopic balloon dilatation (FBD) in children with esophageal anastomotic stricture after surgical repair of esophageal atresia., Methods: All patients undergoing surgery for esophageal atresia and requiring dilatation(s) during a consecutive 15-year period [April 2000-September 2014] were analyzed. Dilatations were performed as day case procedures under general anesthesia using a radial force generating balloon device (Boston Scientific Corporation) by surgeons. Outcomes assessed included - (1) the number of dilatations/patient, (2) effectiveness and (3) need for surgery and (4) complications., Results: One hundred thirty seven patients underwent 625 FBD sessions (median 3 dilations per patient; range 1-24 dilatations). Median age at 1st FBD was 0.74years (range 0.05-16.1years). Balloon catheter sizes ranged from 6mm to 20mm. FBD yielded excellent results in 99 patients (74%), while 17 cases (13%) had mild ongoing dysphagia/dysmotility. Ten patients (7%) required further dilatation(s) to control symptoms. No patient(s) required esophageal stenting. Five cases required G-tube feeds as a result of oral aversion behavior - all of these cases were complex/VACTERL patients. Only 1 minor radiological leak occurred after a dilatation session and this did not require surgical intervention. A single patient (long gap EA TEF) with severe neurological impairment having multiple dilatations and stricture resection ultimately required esophageal replacement. Anti-reflux surgery was performed in 36 patients (26%) for medical therapy resistant GER., Conclusion: FBD for anastomotic stricture(s) following esophageal atresia repair achieved very good outcomes for the majority of EA TEF patients. The procedure can be accomplished safely as indicated by the low complication rate herein reported. Although some children may require more than one dilatation session prompt relief of symptoms can be achieved with a vigilant care program co-ordinated by a multidisciplinary specialist EA TEF team., (Copyright © 2016 Elsevier Inc. All rights reserved.)

We have investigated ammonia adsorption in group two halides (MgI2 and CaBr2) using custom-built apparatus that permits simultaneous neutron diffraction, microwave dielectric characterisation and out-gas mass spectroscopy of solid state materials during ammonia adsorption. Deuterated ammonia was flowed over the sample and the uptake - as measured by mass flow meters, mass spectroscopy and structure - compared with the change in dielectric constant. An excellent correlation between ammonia content and dielectric property was observed and, when linked to diffraction, mass flow and mass spectroscopy data, could be used to determine the amount of ammonia present within the solid. The combination of these techniques could also be used to differentiate physisorbed and metal-coordinated ammonia and explain subtleties in the observed structural transformations.

Ni/Al2O3, Co/Al2O3 and bimetallic Ni(Co)/Al2O3 catalysts were prepared using an impregnation method and employed in CO2 dry reforming of methane under coking-favored conditions. The spent catalysts were carefully characterized using typical characterization technologies and inelastic neutron scattering spectroscopy. The bimetallic catalyst exhibited a superior activity and anti-coking performance compared to Ni/Al2O3, while the most resistant to coking behavior was Co/Al2O3. The enhanced activity of the Ni(Co)/Al2O3 bimetallic catalyst is attributed to the reduced particle size of metallic species and resistance to forming stable filamentous carbon. The overall carbon deposition on the spent bimetallic catalyst is comparable to that of the spent Ni/Al2O3 catalyst, whereas the carbon deposited on the bimetallic catalyst is mainly less-stable carbonaceous species as confirmed by SEM, TPO, Raman and INS characterization. This study provides an in depth understanding of alloy effects in catalysts, the chemical nature of coked carbon on spent Ni-based catalysts and, hopefully, inspires the creative design of a new bimetallic catalyst for dry reforming reactions.

Background: Children with empyema are managed at our center using a protocol-driven clinical care pathway. Chemical fibrinolysis is deployed as first-line management for significant pleural disease. We therefore examined clinical outcome(s) to benchmark standards of care while analyzing disease severity with introduction of the pneumococcal conjugate vaccine., Methods: Medical case-records of children managed at a UK pediatric center were surveyed from Jan 2006 to Dec 2012. Binary logistic regression was utilized to study failure of fibrinolytic therapy. The effects of age, comorbidity, number of days of intravenous antibiotics prior to drainage and whether initial imaging showed evidence of necrotizing disease were also studied., Results: A total of 239 children were treated [age range 4months-19years; median 4years]. A decreasing number of patients presenting year-on-year since 2006 with complicated pleural infections was observed. The majority of children were successfully managed without surgery using antibiotics alone (27%) or a fine-bore chest-drain and urokinase (71%). Only 2% of cases required primary thoracotomy. 14.7% cases failed fibrinolysis and required a second intervention. The only factor predictive of failure and need for surgery was suspicion of necrotizing disease on initial imaging (P=0.002, OR 8.69)., Conclusion: Pediatric patients with pleural empyema have good outcomes when clinical care is led by a multidisciplinary team and protocol driven care pathway. Using a 'less is best' approach few children require surgery., (Copyright © 2016 Elsevier Inc. All rights reserved.)

We demonstrate that the ammonia decomposition reaction catalysed by sodium amide proceeds under a different mechanism to ammonia decomposition over transition metal catalysts. Isotopic variants of ammonia and sodium amide reveal a significant kinetic isotope effect in contrast to the nickel-catalysed reaction where there is no such effect. The bulk composition of the catalyst is also shown to affect the kinetics of the ammonia decomposition reaction.

We demonstrate that non-stoichiometric lithium imide is a highly active catalyst for the production of high-purity hydrogen from ammonia, with superior ammonia decomposition activity to a number of other catalyst materials. Neutron powder diffraction measurements reveal that the catalyst deviates from pure imide stoichiometry under ammonia flow, with active catalytic behaviour observed across a range of stoichiometry values near the imide. These measurements also show that hydrogen from the ammonia is exchanged with, and incorporated into, the bulk catalyst material, in a significant departure from existing ammonia decomposition catalysts. The efficacy of the lithium imide-amide system not only represents a more promising catalyst system, but also broadens the range of candidates for amide-based ammonia decomposition to include those that form imides.

Humans have two, frontally placed eyes and during reading oculomotor and sensory processes are needed to combine the two inputs into a unified percept of the text. Generally, slight vergence errors, i.e., fixation disparities, occur but do not cause double vision since disparate retinal inputs fall into Panum's fusional area, that is, a range of disparity wherein sensory fusion of the two retinal images is achieved. In this study, we report benchmark data with respect to the mean magnitude and range of vertical compared to horizontal fixation disparities for natural reading. Our data clearly fit to an elliptical pattern of Panum's fusional area that corresponds with theoretical estimates. Furthermore, when we examined disparity-driven vergence adjustments during fixations by comparing monocular with binocular reading conditions, we found that only horizontal fixation disparities increased significantly under conditions of monocular stimulation. Also, no significant vertical fine-tuning (vergence adjustment) was observed for vergence eye movements during reading fixations. Thus, horizontal and vertical fixation disparities and vergence adjustments during reading showed quite different characteristics, and this dissociation is directly related to the functional role of vergence adjustments: vertical fusion - and vertical vergence - subserve the maintenance of a single percept and stereopsis by keeping the eyes in register and allowing for horizontal fusional processes to successfully operate over a vertically aligned input. A reliable and stable vertical alignment is, thus, a pre-requisite over which horizontal fusional responses (and depth perception) can work most efficiently - even in a task like reading., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background and Aims: Gastrooesophageal reflux disease (GERD) is a significant problem in children with neurological impairment (NI) with high failure rates for fundoplication. Fundoplication with vagotomy and pyloroplasty (FVP) can improve the outcome by altering the sensory or motor dysfunction associated with the reflux. We report our comparative outcomes for simple fundoplication (SF) and FVP in NI children., Methods: Case records of all patients having fundoplication under a single consultant at a tertiary UK paediatric surgical centre between January 1997 and December 2012 were retrospectively assessed for recurrent symptoms and redo surgery. The data were collected using a Microsoft Excel database and analysed on Graphpad prism software program. Data are median (range). P value<0.05 was considered significant., Results: Data were available for 244 out of 275 patients who underwent fundoplication during this period (157 SF and 87 FVP). Neurological disease or known syndromes were recorded in 158 patients. Thirty-five children had congenital anatomical abnormalities. Laparoscopic fundoplication was done in 37 cases. Revisional surgery for recurrent symptoms was performed in 22 patients. In the neurologically normal children, all of whom had SF, the revision rate was 6.5%. In the NI children the revision rates were 18.5% for SF and 3.9% for FVP, respectively (Fisher's exact, P<0.05). The median time to redo surgery was 10 (1-63) months, and the median time to follow up was 19.5 (2-177) months., Conclusions: There appears to be a significantly lower need for redo surgery following FVP than SF in children with NI., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Humans typically make use of both eyes during reading, which necessitates precise binocular coordination in order to achieve a unified perceptual representation of written text. A number of studies have explored the magnitude and effects of naturally occurring and induced horizontal fixation disparity during reading and non-reading tasks. However, the literature concerning the processing of disparities in different dimensions, particularly in the context of reading, is considerably limited. We therefore investigated vertical vergence in response to stereoscopically presented linguistic stimuli with varying levels of vertical offset. A lexical decision task was used to explore the ability of participants to fuse binocular image disparity in the vertical direction during word identification. Additionally, a lexical frequency manipulation explored the potential interplay between visual fusion processes and linguistic processes. Results indicated that no significant motor fusional responses were made in the vertical dimension (all p-values>.11), though that did not hinder successful lexical identification. In contrast, horizontal vergence movements were consistently observed on all fixations in the absence of a horizontal disparity manipulation. These findings add to the growing understanding of binocularity and its role in written language processing, and fit neatly with previous literature regarding binocular coordination in non-reading tasks., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

This paper presents a new type of process for the cracking of ammonia (NH3) that is an alternative to the use of rare or transition metal catalysts. Effecting the decomposition of NH3 using the concurrent stoichiometric decomposition and regeneration of sodium amide (NaNH2) via sodium metal (Na), this represents a significant departure in reaction mechanism compared with traditional surface catalysts. In variable-temperature NH3 decomposition experiments, using a simple flow reactor, the Na/NaNH2 system shows superior performance to supported nickel and ruthenium catalysts, reaching 99.2% decomposition efficiency with 0.5 g of NaNH2 in a 60 sccm NH3 flow at 530 °C. As an abundant and inexpensive material, the development of NaNH2-based NH3 cracking systems may promote the utilization of NH3 for sustainable energy storage purposes.

The location of hydrogen within Ti-Cr-V-Mo alloys has been investigated during hydrogen absorption and desorption using in situ neutron powder diffraction and inelastic neutron scattering. Neutron powder diffraction identifies a low hydrogen equilibration pressure body-centred tetragonal phase that undergoes a martensitic phase transition to a face-centred cubic phase at high hydrogen equilibration pressures. The average location of the hydrogen in each phase has been identified from the neutron powder diffraction data although inelastic neutron scattering combined with density functional theory calculations show that the local structure is more complex than it appears from the average structure. Furthermore the origin of the change in dissociation pressure and hydrogen trapping on cycling in Ti-Cr-V-Mo alloys is discussed.

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.

We report the experimental investigation of hydrogen storage and release in the lithium amide-lithium hydride composite (Li-N-H) system. Investigation of hydrogenation and dehydrogenation reactions of the system through in situ synchrotron X-ray powder diffraction experiments allowed for the observation of the formation and evolution of non-stoichiometric intermediate species of the form Li1+xNH2-x. This result is consistent with the proposed Frenkel-defect mechanism for these reactions. We observed capacity loss with decreasing temperature through decreased levels of lithium-rich (0.7 ≤ x ≤ 1.0) non-stoichiometric phases in the dehydrogenated material, but only minor changes due to multiple cycles at the same temperature. Annealing of dehydrogenated samples reveals the reduced stability of intermediate stoichiometry values (0.4 ≤ x ≤ 0.7) compared with the end member species: lithium amide (LiNH2) and lithium imide (Li2NH). Our results highlight the central role of ionic mobility in understanding temperature limitations, capacity loss and facile reversibility of the Li-N-H system.

Background: The anatomical defect in congenital diaphragmatic hernia (CDH) can usually be closed primarily but prosthetic patch repair may be required in newborns with a deficient diaphragm. High rates of patch failure and hernia recurrence (up to 50 per cent) have been reported. This study evaluated contemporary outcomes following patch repair of CDH at a UK paediatric surgical centre., Methods: Medical records of newborns undergoing surgery for CDH between 1 February 1990 and 1 November 2010, and attending a multidisciplinary follow-up clinic, were examined. Operative details and patch utilization are reported., Results: Of 118 newborns with CDH, 37 required a patch to the diaphragmatic defect. Gore-Tex® patches were used in 35 and biological Surgisis® patches in two. Eight babies additionally required an abdominal wall patch. Seven infants had an abdominal patch alone with primary diaphragm repair. A total of 102 infants (86·4 per cent) survived after surgery. Two early recurrences were both related to the use of biological patches, leading to revisional surgery with Gore-Tex® patch reconstruction. Diaphragmatic patch use was associated with a greater requirement for intensive cardiovascular and respiratory support, although there was no significant difference in mortality between patch versus primary diaphragm repair. The mortality rate was significantly higher among infants requiring abdominal wall patching (with or without a diaphragmatic patch): 40 per cent (6 of 15) versus 9·7 per cent (10 of 103) (P = 0·006). Postoperative survival rates for infants with a diaphragmatic patch alone, abdominal wall patch alone, and both abdominal and diaphragmatic patches were 86 per cent (25 of 29), 57 per cent (4 of 7) and 63 per cent (5 of 8) respectively., Conclusion: Prosthetic diaphragmatic hernia repair at this centre has a good outcome and low rate of recurrence (5 per cent). The recognition of an inadequate abdominal domain prenatally may additionally prove to be a useful marker for predicting increased mortality in newborns with CDH., (© 2013 British Journal of Surgery Society Ltd. Published by John Wiley & Sons Ltd.)

(1)H, (7)Li, (14)N, and (23)Na high resolution nuclear magnetic resonance (NMR) measurements are reported for fluid solutions of lithium and sodium in anhydrous liquid ammonia across the metal-to-nonmetal transition (MNM transition), paying particular attention to the phenomenon of liquid-liquid phase separation which occurs in the composition/temperature region close to the MNM transition. Our results are discussed in terms of the electronic structure of fluid metal-ammonia solutions at low temperatures (ca. 240 K). We find that the electronic phase transition to the metallic state in these solutions, especially at temperatures close to the liquid-liquid critical consolute temperature, occurs from a nonmetallic, electrolytic solution containing a predominance of electron spin-paired, (diamagnetic) charged bosonic states. The possible implications of these observations to the nature of the liquid-liquid phase separation are discussed, both from the views of N. F. Mott, regarding the MNM transition in sodium-ammonia solutions, and those of R. A. Ogg, regarding the possibility of high-temperature superconductivity in these solutions. Similarities between the electronic structure of metal-ammonia solutions and the high-temperature cuprate superconductors are also briefly emphasized.

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.)

The electron transfer molecules plastoquinone and ubiquinone are formed by the condensation of aromatic head groups with long-chain prenyl diphosphates. In the present paper we report the cloning and characterization of two genes from tomato (Solanum lycopersicum) responsible for the production of solanesyl and decaprenyl diphosphates. SlSPS (S. lycopersicum solanesyl diphosphate synthase) is targeted to the plastid and both solanesol and plastoquinone are associated with thylakoid membranes. A second gene [SlDPS (S. lycopersicum solanesyl decaprenyl diphosphate synthase)], encodes a long-chain prenyl diphosphate synthase with a different subcellular localization from SlSPS and can utilize geranyl, farnesyl or geranylgeranyl diphosphates in the synthesis of C45 and C50 prenyl diphosphates. When expressed in Escherichia coli, SlSPS and SlDPS extend the prenyl chain length of the endogenous ubiquinone to nine and ten isoprene units respectively. In planta, constitutive overexpression of SlSPS elevated the plastoquinone content of immature tobacco leaves. Virus-induced gene silencing showed that SlSPS is necessary for normal chloroplast structure and function. Plants silenced for SlSPS were photobleached and accumulated phytoene, whereas silencing SlDPS did not affect leaf appearance, but impacted on primary metabolism. The two genes were not able to complement silencing of each other. These findings indicate a requirement for two long-chain prenyl diphosphate synthases in the tomato.

The structure of the cubic polymorph of magnesium tetrahydroborate (γ-Mg(BH(4))(2)) has been determined in space group Ia3d from a structural database of the isoelectronic compound SiO(2); this has been corroborated by DFT calculations. The structure is found to concur with that recently determined by Filinchuk et al. (Y. Filinchuk, B. Richter, T. R. Jensen, V. Dmitriev, D. Chernyshov and H. Hagemann, Angew. Chem. Int. Ed., 2011, DOI: 10.1002/anie.201100675). The phase transformations and subsequent decomposition of γ-Mg(BH(4))(2) on heating have been ascertained from variable-temperature synchrotron X-ray diffraction data combined with thermogravimetric and mass spectrometry measurements. At ~160 °C, conversion to a disordered variant of the β-Mg(BH(4))(2) phase (denoted as β') is observed along with a further unidentified polymorph. There is evidence of amorphous phases during decomposition but there is no direct crystallographic indication of the existence of Mg(B(12)H(12)) or other intermediate Mg-B-H compounds. MgH(2) and finally Mg are observed in the X-ray diffraction data after decomposition.