RESUMEN
Anthropogenic nitrogen inputs cause major negative environmental impacts, including emissions of the important greenhouse gas N2O. Despite their importance, shifts in terrestrial N loss pathways driven by global change are highly uncertain. Here we present a coupled soil-atmosphere isotope model (IsoTONE) to quantify terrestrial N losses and N2O emission factors from 1850-2020. We find that N inputs from atmospheric deposition caused 51% of anthropogenic N2O emissions from soils in 2020. The mean effective global emission factor for N2O was 4.3 ± 0.3% in 2020 (weighted by N inputs), much higher than the surface area-weighted mean (1.1 ± 0.1%). Climate change and spatial redistribution of fertilisation N inputs have driven an increase in global emission factor over the past century, which accounts for 18% of the anthropogenic soil flux in 2020. Predicted increases in fertilisation in emerging economies will accelerate N2O-driven climate warming in coming decades, unless targeted mitigation measures are introduced.
Asunto(s)
Gases de Efecto Invernadero , Óxido Nitroso , Agricultura , Atmósfera , Nitrógeno/metabolismo , Óxido Nitroso/metabolismo , SueloRESUMEN
For two decades now, partial nitritation anammox (PNA) systems were suggested to more efficiently remove nitrogen (N) from mainstream municipal wastewater. Yet to date, only a few pilot-scale systems and even fewer full-scale implementations of this technology have been described. Process instability continues to restrict the broad application of PNA. Especially problematic are insufficient anammox biomass retention, the growth of undesired aerobic nitrite-oxidizers, and nitrous oxide (N2O) emissions. In this study, a two-stage mainstream pilot-scale PNA system, consisting of three reactors (carbon pre-treatment, nitritation, anammox - 8 m3 each), was operated over a year, treating municipal wastewater. The aim was to test whether both, robust autotrophic N removal and high effluent quality, can be achieved throughout the year. A second aim was to better understand rate limiting processes, potentially affecting the overall performance of PNA systems. In this pilot study, excellent effluent quality, in terms of inorganic nitrogen, was accomplished (average effluent concentrations: 0.4 mgNH4-N/L, 0.1 mgNO2-N/L, 0.9 mgNO3-N/L) even at wastewater temperatures previously considered problematic (as low as 8 °C). N removal was limited by nitritation rates (84 ± 43 mgNH4-N/L/d), while surplus anammox activity was observed at all times (178 ± 43 mgN/L/d). Throughout the study, nitrite-oxidation was maintained at a low level (<2.5% of ammonium consumption rate). Unfortunately, high N2O emissions from the nitritation stage (1.2% of total nitrogen in the influent) were observed, and, based on natural isotope abundance measurements, could be attributed to heterotrophic denitrification. In situ batch experiments were conducted to identify the role of dissolved oxygen (DO) and organic substrate availability in N2O emission-mitigation. The addition of organic substrate, to promote complete denitrification, was not successful in decreasing N2O emission, but increasing the DO from 0.3 to 2.9 mgO2/L decreased N2O emissions by a factor of 3.4.
RESUMEN
The development of new wastewater treatment processes can assist in reducing the impact of wastewater treatment on the environment. The recently developed partial nitritation anammox (PNA) process, for example, consumes less energy for aeration and reduces nitrate in the effluent without requiring additional organic carbon. However, achieving stable nitritation (ammonium oxidation; NH4+ â NO2-) at mainstream conditions (T = 10-25 °C, C:N > 10, influent ammonium < 50 mgNH4-N/L and effluent < 1 mgNH4-N/L) remains challenging. This study explores the potential and mechanism of nitrite-oxidizing bacteria (NOB) suppression in a bottom-fed sequencing batch reactor (SBR). Two bench-scale (11 L) reactors and a pilot-scale reactor (8 m3) were operated for over a year and were fed with organic substrate depleted municipal wastewater. Initially, nitratation (nitrite oxidation; NO2- â NO3-) occurred occasionally until an anaerobic phase was integrated into the operating cycle. The introduction of the anaerobic phase effectively suppressed the regrowth of NOB while nitritation was stable over 300 days, down to 8 °C and at ammonium influent concentrations < 25 mgNH4-N/L. Batch experiments and process data revealed that parameters typically affecting NOB growth (e.g., dissolved oxygen, alkalinity, trace elements, lag-phase after anoxia, free nitrous acid (FNA), free ammonia (FA), pH, sulfide, or solids retention time (SRT)) could not fully explain the suppression of nitratation. Experiments in which fresh nitrifying microbial biomass was added to the nitritation system indicated that NOB inactivation explained NOB suppression better than NOB washout at high SRT. This study concludes that bottom-fed SBRs with anaerobic phases allow for stable nitritation over a broad range of operational parameters. Coupling this type of SBR to an anammox reactor can enable efficient mainstream anammox-based wastewater treatment.
Asunto(s)
Compuestos de Amonio , Nitritos , Bacterias , Reactores Biológicos/microbiología , Nitrógeno , Oxidación-Reducción , Aguas del Alcantarillado , Aguas ResidualesRESUMEN
AIM: To investigate the associations of self-perceived competence in diabetes management and autonomy support from healthcare providers with diabetes distress in adults with Type 1 diabetes mellitus that is not optimally controlled [HbA(1c) ≥ 64 mmol/mol (8.0%)]. METHODS: This cross-sectional study comprised blood sampling and three self-report questionnaires, the Problem Areas in Diabetes scale, the Perceived Competence in Diabetes Scale and a measure of autonomy support by healthcare providers, the Health Care Climate Questionnaire. We fitted blockwise linear regression models to assess the associations between Problem Areas in Diabetes score and the variables of interest (autonomy support and perceived diabetes competence), controlling for clinical and sociodemographic variables. RESULTS: Of the study sample [n = 178; mean age 36.7 (±10.7) years], 31.5% had long-term complications and 43.2% reported elevated (≥40) Problem Areas in Diabetes scores. A significant negative association was found between autonomy support and Problem Areas in Diabetes score (B = -3.61, P = 0.001), indicating that lower autonomy support was associated with greater diabetes distress. When perceived competence was controlled, it mediated the association of autonomy support with diabetes distress, reducing it to non-significance. There was a significant negative association between perceived competence and Problem Areas in Diabetes score (B = -8.89, P < 0.001), indicating that lower perceived competence was associated with greater perceived distress. CONCLUSIONS: There was an indirect (fully mediated) relationship between autonomy support and diabetes distress; autonomy support was associated with increased perceived competence, which, in turn, was associated with reduced distress. Healthcare providers' communication styles enhancing perceived competence through autonomy support may contribute to effective treatment for people with Type 1 diabetes and suboptimum glycaemic control.
Asunto(s)
Complicaciones de la Diabetes/prevención & control , Diabetes Mellitus Tipo 1/terapia , Hiperglucemia/prevención & control , Cooperación del Paciente , Autonomía Personal , Autocuidado , Estrés Psicológico/prevención & control , Adulto , Automonitorización de la Glucosa Sanguínea , Terapia Combinada , Estudios Transversales , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/psicología , Femenino , Hemoglobina Glucada/análisis , Conocimientos, Actitudes y Práctica en Salud , Hospitales Universitarios , Humanos , Masculino , Persona de Mediana Edad , Noruega , Servicio Ambulatorio en Hospital , Educación del Paciente como Asunto , Autoinforme , Estrés Psicológico/complicacionesRESUMEN
Intellectual disabilities (IDs) and autism spectrum disorders link to human APC inactivating gene mutations. However, little is known about adenomatous polyposis coli's (APC's) role in the mammalian brain. This study is the first direct test of the impact of APC loss on central synapses, cognition and behavior. Using our newly generated APC conditional knock-out (cKO) mouse, we show that deletion of this single gene in forebrain neurons leads to a multisyndromic neurodevelopmental disorder. APC cKO mice, compared with wild-type littermates, exhibit learning and memory impairments, and autistic-like behaviors (increased repetitive behaviors, reduced social interest). To begin to elucidate neuronal changes caused by APC loss, we focused on the hippocampus, a key brain region for cognitive function. APC cKO mice display increased synaptic spine density, and altered synaptic function (increased frequency of miniature excitatory synaptic currents, modestly enhanced long-term potentiation). In addition, we found excessive ß-catenin levels and associated changes in canonical Wnt target gene expression and N-cadherin synaptic adhesion complexes, including reduced levels of presenilin1. Our findings identify some novel functional and molecular changes not observed previously in other genetic mutant mouse models of co-morbid cognitive and autistic-like disabilities. This work thereby has important implications for potential therapeutic targets and the impact of their modulation. We provide new insights into molecular perturbations and cell types that are relevant to human ID and autism. In addition, our data elucidate a novel role for APC in the mammalian brain as a hub that links to and regulates synaptic adhesion and signal transduction pathways critical for normal cognition and behavior.
Asunto(s)
Proteína de la Poliposis Adenomatosa del Colon/metabolismo , Trastorno Autístico/fisiopatología , Trastornos del Conocimiento/fisiopatología , Proteína de la Poliposis Adenomatosa del Colon/genética , Animales , Trastorno Autístico/patología , Cadherinas/metabolismo , Trastornos del Conocimiento/patología , Espinas Dendríticas/patología , Espinas Dendríticas/fisiología , Modelos Animales de Enfermedad , Potenciales Postsinápticos Excitadores/fisiología , Hipocampo/patología , Hipocampo/fisiopatología , Potenciación a Largo Plazo/fisiología , Masculino , Aprendizaje por Laberinto/fisiología , Ratones Noqueados , Potenciales Postsinápticos Miniatura/fisiología , Células Piramidales/patología , Células Piramidales/fisiopatología , Conducta Social , Memoria Espacial/fisiología , Conducta Estereotipada/fisiología , Sinapsis/patología , Sinapsis/fisiología , Vía de Señalización Wnt/fisiología , beta Catenina/metabolismoRESUMEN
We describe the first long-term implementation of the radiocarbon (¹4C) method to study the share of biogenic (%Bio C) and fossil (%Fos C) carbon in combustion CO2. At five Swiss incinerators, a total of 24 three-week measurement campaigns were performed over 1 year. Temporally averaged bag samples were analyzed for ¹4CO2 by accelerator mass spectrometry. Significant differences between the plants in the share of fossil CO2 were observed, with annual mean values from 43.4 ± 3.9% to 54.5 ± 3.1%. Variations can be explained by the waste composition of the respective plant. Based on our dataset, an average value of 48 ± 4%Fos C was determined for waste incineration in Switzerland. No clear annual trend in %Fos C was observed for four of the monitored incinerators, while one incinerator showed considerable variations, which are likely due to the separation and temporary storage of bulky goods.
Asunto(s)
Dióxido de Carbono/química , Combustibles Fósiles/análisis , Incineración , Biocombustibles , Radioisótopos de Carbono/análisis , Espectrometría de MasasRESUMEN
A field application of the radiocarbon ((14)C) method was developed to determine the ratio of biogenic vs. fossil CO(2) emissions from waste-to-energy plants (WTE). This methodology can be used to assign the Kyoto relevant share of fossil CO(2) emissions, which is highly relevant for emission budgets and emission trading. Furthermore, heat and electricity produced by waste incinerators might be labelled depending on the fossil or biogenic nature of the primary energy source. The method development includes representative on-site CO(2) absorption and subsequent release in the laboratory. Furthermore, a reference value for the (14)C content of pure biogenic waste (f(M,bio)) was determined as 1.130+/-0.038. Gas samples for (14)CO(2) analysis were taken at three WTEs during one month each. Results were compared to an alternative approach based on mass and energy balances. Both methods were in excellent agreement and indicated a fraction of biogenic CO(2) slightly above 50%.
Asunto(s)
Dióxido de Carbono/análisis , Radioisótopos de Carbono/análisis , Incineración , Método de Montecarlo , Estándares de ReferenciaRESUMEN
Most multiple sclerosis (MS) patients experience some sexual, bladder and/or bowel dysfunction during the course of the disease--one of MS most disabling features. This study estimated the frequency of these problems among patients, two to five years after diagnosis, and investigated how these problems are associated with health-related quality of life (using the Multiple Sclerosis Quality of Life-54 questionnaire). The study population comprised a cohort of patients (n = 56), diagnosed in a three-year period, in Hordaland County, Norway. The patients were examined clinically, including scoring of the Expanded Disability Status Scale (EDSS), and completed questionnaires related to bowel and bladder dysfunction, sexual problems and health-related quality of life. More than half the patients had bladder and sexual problems. The frequency of self-reported bladder problems corresponded to the relatively high levels of residual urine found. The presence of these problems was associated with lower scores on the quality of life scales. Further, the bowel problems reported were markedly associated with the quality of life scores. Since treatments and preventive strategies can manage many of these problems, we suggest increasing the focus on these aspects of the disease when consulting patients, including at early stages.
Asunto(s)
Enfermedades Intestinales/epidemiología , Esclerosis Múltiple Crónica Progresiva/epidemiología , Esclerosis Múltiple Recurrente-Remitente/epidemiología , Disfunciones Sexuales Fisiológicas/epidemiología , Trastornos Urinarios/epidemiología , Adolescente , Adulto , Femenino , Humanos , Intestinos/fisiología , Masculino , Persona de Mediana Edad , Prevalencia , Calidad de Vida , Encuestas y Cuestionarios , Factores de Tiempo , Vejiga Urinaria/fisiologíaRESUMEN
51 patients aged 68 (range 52-81) years with lower urinary tract symptoms compatible with obstruction from benign prostatic hyperplasia were treated with interstitial laser coagulation (ILC). Postoperative urinary retention lasting less than one week was seen in the majority of cases. All patients were followed up for three months and ten cases had further follow-up after one year. Three months after treatment the international prostate symptom score decreased from 23.3 +/- 0.7 to 8.9 +/- 0.8 and was 10.2 +/- 2.1 after one year. Peak urinary flow increased concomitantly from 8.3 +/- 0.4 to 12.2 +/- 0.7 at three months and was 11.5 +/- 1.4 ml/sec after one year. Three patients received other, additional treatment because the ILC-treatment failed. In conclusion, interstitial laser coagulation had marked effects on symptoms, whereas the effects on objective parameters were less pronounced in this selected group of patients. However, more extensive follow-up, is essential for further evaluation of this new treatment procedure.
Asunto(s)
Coagulación con Láser/métodos , Hiperplasia Prostática/cirugía , Anciano , Estudios de Evaluación como Asunto , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Psittacosis may occur in epidemic or sporadic form. We report an outbreak of avian and human psittacosis associated with an aviary in Philadelphia, Pa. The epidemic spread among birds in the aviary and then to men and women who were in contact with the birds. Chlamydia psittaci was cultured from infected birds, and the human patients were evaluated clinically and serologically. After proper treatment of the birds, cleaning of their cages, and institution of appropriate bird-handling techniques, the outbreak among the birds resolved. The human patients were treated, and no subsequent cases have been seen.
Asunto(s)
Enfermedades de las Aves/epidemiología , Brotes de Enfermedades/veterinaria , Psitacosis/epidemiología , Psitacosis/veterinaria , Adolescente , Adulto , Animales , Enfermedades de las Aves/transmisión , Aves , Femenino , Humanos , Masculino , Pennsylvania/epidemiología , ZoonosisRESUMEN
The existence of some form of specifically active A or B blood group substance in the saliva of group A1, A2 and B non-secretors was demonstrated. Significant inhibition of agglutination results were obtained when the salivas of these non-secretors were examined in a test procedure using anti-A + B (group O) serum and group AX red cells. Native saliva specimens from group A1, A2 and B secretors and non-secretors were filtered on Sephadex G-200 columns. The eluates were tested for blood group activity by inhibition of agglutination and for relative carbohydrate and protein content. A main excluded glycoprotein, blood group-active fraction was detected in all samples of saliva examined.
Asunto(s)
Sistema del Grupo Sanguíneo ABO , Saliva/metabolismo , Animales , Reacciones Antígeno-Anticuerpo , Reacciones Cruzadas , Femenino , Pruebas de Hemaglutinación , Humanos , Sueros Inmunes/farmacología , Masculino , Embarazo , PorcinosRESUMEN
Rabbits were selected on the basis of distinctly higher titers of preexisting heteroagglutinins in their normal sera for human group A1 and A2 erythrocytes than for group B and especially group O. They were injected intravenously with increasing volumes of either of two pools of human group A1 secretor saliva. Comparative titrations between the reimmunization and the 7--14-day postimmune sera clearly demonstrated that all the rabbits responded with increases in the titers of the agglutinins directed against human group A1 and group A2 red blood cells that averaged approximately 250-fold; whereas, the titers of those active against the group B cells increased but 9.2 times and of those reacting with the group O cells only by an average of 2.8 times.
Asunto(s)
Sistema del Grupo Sanguíneo ABO/inmunología , Anticuerpos Heterófilos/biosíntesis , Inmunoglobulina A Secretora/inmunología , Inmunoglobulina A/inmunología , Animales , Humanos , Inmunización , Esquemas de Inmunización , ConejosRESUMEN
A-like and non-A-like rabbits were injected with human group A1 and A2 secretor saliva. The sera were then examined for their agglutinative capacity against human group A1, A2, B and O erythrocytes before and after sequential adsorption with group O, B and A2 erythrocytes. The A-like rabbits produced specific anti-A1 agglutinins when injected with group A1 saliva but not when injected with group A2 saliva. The non-A-like rabbits produced anti-A and anti-A1 agglutinins in response to the A1 antigen but only anti-A agglutinins when group A2 saliva was injected. These experiments support the interpretation that a qualitative difference exists between subgroups A1 and A2. The non-A-like rabbits also formed cross-reacting antibodies as shown by the increase in the agglutinins reactive with human group B red cells.
Asunto(s)
Sistema del Grupo Sanguíneo ABO/inmunología , Aglutininas/inmunología , Sueros Inmunes , Saliva/inmunología , Aglutinación , Animales , Formación de Anticuerpos , Complejo Antígeno-Anticuerpo , Hemaglutinación , Humanos , ConejosRESUMEN
A-like and non-A-like rabbits were injected with human group A1 erythrocytes. The rabbit sera were examined serologically for their hemagglutination patterns with human red cells of groups A1 and A2 before and after sequential adsorption with human group O, B and A2 erythrocytes. The A-like rabbits produced specific anti-A1 heteroagglutinins that resisted further adsorptions with group A2 cells. The tissues of A-like rabbits obviously do not contain antigenic configurations equivalent to those on human group A1 erythrocytes. Cross-reacting antibodies were also formed, by the non-A-like rabbits especially, as evidenced by the increased titer of agglutinins reactive with human group B red cells.
Asunto(s)
Sistema del Grupo Sanguíneo ABO/inmunología , Aglutininas/inmunología , Sueros Inmunes , Aglutinación , Animales , Reacciones Antígeno-Anticuerpo , Eritrocitos/inmunología , Hemaglutinación , Humanos , ConejosRESUMEN
A study is made of the influence on hemagglutination of various physicochemical parameters, such as: cell shape, cell distance, extracellular colloid-osmotic pressure, degree of hydration of the cell surface, and cell zeta-potential. To a varying extent these are changed by: the addition of divers soluble polymers, the action of enzymes, the presence of various salt ions, centrifugation, agglomeration at low ionic strength, complex coacervation with cationic polymers, and the interaction with different kinds of antibodies. Among the more important parameters are cell distance and cell shape (particularly when the latter tends to spiculation), while the influence of zeta-potential appears to be of fairly minor consequence. The action of dissolved polymers is mediated through polymer bridging, increase in extracellular colloid-osmotic pressure, decrease of cell surface hydration, and change in cell shape. A peculiarity of dextran is that in addition to all of the above, it causes pronounced erythrocytic spiculation.
Asunto(s)
Hemaglutinación , Complejo Antígeno-Anticuerpo , Centrifugación , Fenómenos Químicos , Química Física , Electricidad , Membrana Eritrocítica , Bromuro de Hexadimetrina/farmacología , Humanos , Cinética , Sustancias Macromoleculares , Concentración Osmolar , Polímeros , TermodinámicaRESUMEN
Four random examples of group Ax erythrocytes were tested with anti-A sera (group B). Microscopic examination demonstrated a high incidence of reactivity of these cells with the anti-A sera (group B) obtained after immunization with group A substance.