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The stability of the two-stage partial nitrification-anammox (PN/A) system was compromised by the inappropriate conversion of insoluble organic matter. In response, a sludge redistribution strategy was implemented. Through the redistribution of PN sludge and anammox sludge in the two-stage PN/A system, a transition was made to the Anammox-single stage PN/A (A-PN/A) system. This specific functional reorganization, facilitated by the rapid reorganization of microbial communities, has the potential to significantly decrease the current risk of suppression. The results of the study showed that implementing the sludge redistribution strategy led to a substantial enhancement in the total nitrogen removal rate (TNRR) by 87.51%, accompanied by a significant improvement of 34.78% in the chemical oxygen demand removal rate (CRR). Additionally, this approach resulted in a remarkable two-thirds reduction in the aeration requirements. High-throughput sequencing revealed that the strategy enriched anammox and ammonia-oxidizing bacteria while limiting denitrifying bacteria, as confirmed by quantitative polymerase chain reaction analysis. Furthermore, the principal component analysis revealed that the location and duration of aeration had direct and indirect effects on functional gene expression and the evolution of microbial communities. This study emphasizes the potential benefits of restructuring microbial communities through a sludge redistribution strategy, especially in integrated systems that encounter challenges with suppression.
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Nitrificación , Aguas del Alcantarillado , Aguas del Alcantarillado/microbiología , Desnitrificación , Oxidación Anaeróbica del Amoníaco , Reactores Biológicos/microbiología , Oxidación-Reducción , NitrógenoRESUMEN
Aim: To test whether the occupancy of shorebirds has changed in the eastern Canadian Arctic, and whether these changes could indicate that shorebird distributions are shifting in response to long-term climate change. Location: Foxe Basin and Rasmussen Lowlands, Nunavut, Canada. Methods: We used a unique set of observations, made 25 years apart, using general linear models to test if there was a relationship between changes in shorebird species' occupancy and their species temperature Index, a simple version of a species climate envelope. Results: Changes in occupancy and density varied widely across species, with some increasing and some decreasing. This is despite that overall population trends are known to be negative for all of these species based on surveys during migration. The changes in occupancy that we observed were positively related to the species temperature index, such that the warmer-breeding species appear to be moving into these regions, while colder-breeding species appear to be shifting out of the regions, likely northward. Main Conclusions: Our results suggest that we should be concerned about declining breeding habitat availability for bird species whose current breeding ranges are centered on higher and colder latitudes.
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Introduction The virtual fracture clinic (VFC) can be an effective means of managing specific musculoskeletal injuries, including through protocol-driven direct discharge from the emergency department (ED) or minor injury unit (MIU). This study aimed to measure the efficiency of the VFC triage process while quantifying patient satisfaction after direct discharge from the VFC without routine face-to-face review. Methods We conducted a retrospective analysis of a prospectively collected database to ascertain VFC outcomes for 9064 patients from February 2017 to July 2018. We analysed consultant variation in VFC review and the mean time taken per patient. Patient satisfaction was investigated in 100 chronological patients initially managed via the VFC. Results The mean time to triage each patient was 74 seconds, and a mean of 503 patients was triaged each month. The telephone helpline received a mean of 0.9 calls per week. Seventy-seven percent of patients stated they were happy to be managed without a fracture clinic appointment, and 82% of patients received virtual leaflets in the ED or MIU as per protocol. The number of fracture clinic appointments was reduced by 24% as patients were discharged directly or seen instead by allied health professionals. The median patient satisfaction with VFC management was 90%, and the mean satisfaction with VFC communication was 80%. Conclusion Virtual review of fracture clinic referral enables stratification of patients according to clinical urgency and saves patients from attending unnecessary appointments. This is achieved in a patient population generally satisfied with their overall management. Our study results support the growing trend of VFCs as pivotal systems in streamlining the care of musculoskeletal injuries while adhering to British Orthopaedic Association Standards for Trauma guidelines for Fracture Clinic Services.
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Climate change has been implicated in an increased number of distributional shifts of marine species during the last century. Nonetheless, it is unclear whether earlier climatic fluctuations had similar impacts. We use ancient DNA to investigate the long-term spawning distribution of the Northeast Arctic cod (skrei) which performs yearly migrations from the Barents Sea towards spawning grounds along the Norwegian coast. The distribution of these spawning grounds has shifted northwards during the last century, which is thought to be associated with food availability and warming temperatures. We genetically identify skrei specimens from Ruskeneset in west Norway, an archaeological site located south of their current spawning range. Remarkably, 14C analyses date these specimens to the late Holocene, when temperatures were warmer than present-day conditions. Our results either suggest that temperature is not the only driver influencing the spawning distribution of Atlantic cod, or could be indicative of uncertainty in palaeoclimate reconstructions in this region. Regardless, our findings highlight the utility of aDNA to reconstruct the historical distribution of economically important fish populations and reveal the complexity of long-term ecological interactions in the marine environment.
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ADN Antiguo , Gadus morhua , Animales , Cambio Climático , Peces , Gadus morhua/genética , TemperaturaRESUMEN
Metal homeostasis is integral to normal plant growth and development. During plant-pathogen interactions, the host and pathogen compete for the same nutrients, potentially impacting nutritional homeostasis. Our knowledge of outcome of the interaction in terms of metal homeostasis is still limited. Here, we employed the X-ray fluorescence microscopy (XFM) beamline at the Australian Synchrotron to visualize and analyse the fate of nutrients in wheat leaves infected with Pyrenophora tritici-repentis, a necrotrophic fungal pathogen. We sought to (i) evaluate the utility of XFM for sub-micron mapping of essential mineral nutrients and (ii) examine the spatiotemporal impact of a pathogen on nutrient distribution in leaves. XFM maps of K, Ca, Fe, Cu, Mn, and Zn revealed substantial hyperaccumulation within, and depletion around, the infected region relative to uninfected control samples. Fungal mycelia were visualized as thread-like structures in the Cu and Zn maps. The hyperaccumulation of Mn in the lesion and localized depletion in asymptomatic tissue surrounding the lesion was unexpected. Similarly, Ca accumulated at the periphery of the symptomatic region and as microaccumulations aligning with fungal mycelia. Collectively, our results highlight that XFM imaging provides the capability for high-resolution mapping of elements to probe nutrient distribution in hydrated diseased leaves in situ.
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Nutrientes , Sincrotrones , Ascomicetos , Australia , Microscopía Fluorescente , Rayos XRESUMEN
BACKGROUND: The relation between systolic blood pressure (sBP) on admission and the extent of fluid re-distribution in patients with acute heart failure (AHF) remains unclear. This study aimed to investigate this relation. METHODS: We enrolled consecutive patients who were admitted for AHF in our cardiology department and divided them into three groups according to the tertiles of sBP on admission as follows: low, intermediate, and high sBP groups. Weight changes and estimated relative plasma volume changes (ΔePV) on admission and 24h later were determined in each patient. ΔePV were calculated with the Strauss formula using hemoglobin and hematocrit levels. Univariate and multiple regression analyses were performed to investigate the relation between sBP and ΔePV. RESULTS: The ΔePV of low, intermediate, and high sBP groups were 104.3%, 108.2%, and 121.3%, respectively. High sBP group showed a significantly larger ΔePV than the other two groups (p<0.001 and 0.004, respectively). The body weight of patients in the high sBP group slightly but significantly decreased within 24h (-0.64±0.92kg, p=0.002). The initial sBP had a significant correlation with ΔePV (R2, 0.295; p<0.001). Multiple regression analysis showed significant association between initial sBP with ΔePV. CONCLUSIONS: These results indicate that large amounts of extravasated fluid existed on admission in patients with a high initial sBP. The sBP on admission could be a simple and useful indicator for the extent of fluid re-distribution in AHF.
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Presión Sanguínea/fisiología , Insuficiencia Cardíaca/fisiopatología , Admisión del Paciente/estadística & datos numéricos , Líquido Pericárdico/fisiología , Enfermedad Aguda , Anciano , Biomarcadores/análisis , Determinación de la Presión Sanguínea , Peso Corporal/fisiología , Femenino , Humanos , Hidrodinámica , Masculino , Persona de Mediana Edad , Pronóstico , Análisis de RegresiónRESUMEN
Reductive transformation of nitroaromatic compounds is a central step in its remediation in wastewater, and therefore has invoked extensive catalytical research with rare metals such as palladium (Pd). Herein, we report Pantoea sp. IMH assisted biosynthesis for Pd@NC as an efficient catalyst for the reduction of nitroaromatics. Multiple complementary characterization results for Pd@NC evidenced the evenly dispersed Pd NPs on an N-doped carbon support. Pd@NC exhibited the superior catalytic activity in the reduction of nitroaromatic compounds (4-nitrophenol, 2-nitroaniline, 4-nitroaniline, and 2,6-dichloro-4-nitroaniline). The origin of the catalytic activity was explained by its unique electronic structure, as explored with X-ray absorption near-edge structure (XANES) spectroscopy and density functional theory (DFT) calculations. XANES analysis revealed an increase of 25.6% in the d-hole count in Pd@NC compared with Pd°, as the result of pd hybridization. In agreement with our experimental observations, DFT calculations suggested the formation of Pd-C bonds and charge re-distribution between Pd and the carbon layer, which contributed to the superior catalytic activity of Pd@NC.
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Carbono/metabolismo , Nanopartículas del Metal/química , Nitrógeno/metabolismo , Paladio/metabolismo , Pantoea/metabolismo , Biotransformación , Catálisis , Teoría Funcional de la Densidad , Tecnología Química Verde , Oxidación-Reducción , Espectroscopía de Absorción de Rayos XRESUMEN
INTRODUCTION: The purpose of this investigation was to: (1) to determine the reliability of rectus femoris muscle cross-sectional area and echo intensity obtained using panoramic ultrasound imaging during seated and supine lying positions before and after a 5-minute rest period and (2) to determine the influence of body position and rest period on the magnitude of rectus femoris muscle cross-sectional area and echo intensity measurements. METHODS: A total of 23 males and females (age = 21.5 ± 1.9 years) visited the laboratory on two separate occasions. During each visit, panoramic ultrasound images of the rectus femoris were obtained in both a seated and a supine position before (T1) and after a 5-minute (T2) rest period to quantify any potential changes in either muscle cross-sectional area and/or echo intensity. RESULTS: None of the muscle cross-sectional area or echo intensity measurements exhibited systematic variability, and the ICCs were 0.98-0.99 and 0.88-0.91, and the coefficients of variation were ≤ 3.9% and ≤ 8.2% for muscle cross-sectional area and echo intensity, respectively. Our results indicated that muscle cross-sectional area was greater in the seated than supine position, whereas echo intensity was greater in the supine position. Further, echo intensity increased in the seated position from T1 to T2. CONCLUSION: Both rectus femoris muscle cross-sectional area and echo intensity may be reliably measured in either a seated or supine lying position before or after a 5-minute rest period. Aside from echo intensity in the seated position, rest period had no influence on the magnitude of muscle cross-sectional area or echo intensity. Comparison of muscle cross-sectional area values that are obtained in different body positions is ill-advised.
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Road deposited pollutants (build-up) are continuously re-distributed by external factors such as traffic and wind turbulence, influencing stormwater runoff quality. However, current stormwater quality modelling approaches do not account for the re-distribution of pollutants. This undermines the accuracy of stormwater quality predictions, constraining the design of effective stormwater treatment measures. This study, using over 1000 data points, developed a Bayesian Network modelling approach to investigate the re-distribution of pollutant build-up on urban road surfaces. BTEX, which are a group of highly toxic pollutants, was the case study pollutants. Build-up sampling was undertaken in Shenzhen, China, using a dry and wet vacuuming method. The research outcomes confirmed that the vehicle type and particle size significantly influence the re-distribution of particle-bound BTEX. Compared to heavy-duty traffic in commercial areas, light-duty traffic dominates the re-distribution of particles of all size ranges. In industrial areas, heavy-duty traffic re-distributes particles >75⯵m, and light-duty traffic re-distributes particles <75⯵m. In residential areas, light-duty traffic re-distributes particles >300⯵m and <75⯵m and heavy-duty traffic re-distributes particles in the 300-150⯵m range. The study results provide important insights to improve stormwater quality modelling and the interpretation of modelling outcomes, contributing to safeguard the urban water environment.
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PURPOSE: Objects falling outside of the true elliptical field-of-view (FOV) in Propeller imaging show unique aliasing artifacts. This study proposes a de-aliasing approach to restore the signal intensities in Propeller images without extra data acquisition. MATERIALS AND METHODS: Computer simulation was performed on the Shepp-Logan head phantom deliberately placed obliquely to examine the signal aliasing. In addition, phantom and human imaging experiments were performed using Propeller imaging with various readouts on a 3.0 Tesla MR scanner. De-aliasing using the proposed method was then performed, with the first low-resolution single-blade image used to find out the aliasing patterns in all the single-blade images, followed by standard Propeller reconstruction. The Propeller images without and with de-aliasing were compared. RESULTS: Computer simulations showed signal loss at the image corners along with aliasing artifacts distributed along directions corresponding to the rotational blades, consistent with clinical observations. The proposed de-aliasing operation successfully restored the correct images in both phantom and human experiments. CONCLUSION: The de-aliasing operation is an effective adjunct to Propeller MR image reconstruction for retrospective restoration of aliased signals.
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Interpretación de Imagen Asistida por Computador/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Artefactos , Simulación por Computador , Fantasmas de Imagen , Estudios RetrospectivosRESUMEN
Various hydrothermal treatment methods, including hydrothermal carbonization, liquefaction and sub/super-critical water gasification, have been applied to the disposal of sewage sludge for producing bio-materials or bio-fuels. It has become a research hotspot whether the heavy metals contained in sewage sludge can be well treated/stabilized after the hydrothermal treatments. This review firstly summarized the methods of assessing heavy metals' contamination level/risk and then discussed the migration and transformation behaviors of heavy metals from the following aspects: the effect of reaction temperature, the effect of additives (catalysts and other biomass), the effect of the type of solvent and the effect of reaction time. This review can provide an important reference for the further study of the migration and transformation behaviors of heavy metals during the hydrothermal treatment of sewage sludge.
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Metales Pesados/análisis , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/análisis , Biomasa , Catálisis , Metales Pesados/química , Temperatura , Contaminantes Químicos del Agua/químicaRESUMEN
Despite the high prevalence and potential negative consequences of feeding disorders in children with autism spectrum disorder (ASD), there are surprisingly few studies that examine the efficacy of treatment exclusively with these children. Children with feeding disorders also frequently exhibit packing (holding or pocketing food without swallowing). Investigators have evaluated procedures in the general pediatric population to treat packing, and some have shown that procedures need to be combined to form an effective treatment. Although investigators have evaluated the efficacy of re-distribution, swallow facilitation, and a chaser, these procedures have not been evaluated specifically with children with ASD. Prior to the current investigation, we successfully used nonremoval procedures to increase acceptance of pureed foods and liquids and decrease the inappropriate mealtime behavior of two children diagnosed with ASD and feeding problems; however, in each case, packing emerged during initial treatment. We then used different combinations of re-distribution, swallow facilitation, and chaser treatments to decrease packing for both children.