Multiyear methane and nitrous oxide emissions in different irrigation management under long-term continuous rice rotation in Arkansas.

Rice paddies are one of the major sources of anthropogenic methane (CH4 ) emissions. The alternate wetting and drying (AWD) irrigation management has been shown to reduce CH4 emissions and total global warming potential (GWP) (CH4 and nitrous oxide [N2 O]). However, there is limited information about utilizing AWD management to reduce greenhouse gas (GHG) emissions from commercial-scale continuous rice fields. This study was conducted for five consecutive growing seasons (2015-2019) on a pair of adjacent fields in a commercial farm in Arkansas under long-term continuous rice rotation irrigated with either continuously flooded (CF) or AWD conditions. The cumulative CH4 emissions in the growing season across the two fields and 5 years ranged from 41 to 123 kg CH4 -C ha-1 for CF and 1 to 73 kg CH4 -C ha-1 for AWD. On average, AWD reduced CH4 emissions by 73% relative to CH4 emissions in CF fields. Compared to N2 O emissions, CH4 emissions dominated the GWP with an average contribution of 91% in both irrigation treatments. There was no significant variation in grain yield (7.3-11.9 Mg ha-1 ) or growing season N2 O emissions (-0.02 to 0.51 kg N2 O-N ha-1 ) between the irrigation treatments. The yield-scaled GWP was 368 and 173 kg CO2 eq. Mg-1 season-1 for CF and AWD, respectively, showing the feasibility of AWD on a commercial farm to reduce the total GHG emissions while sustaining grain yield. Seasonal variations of GHG emissions observed within fields showed total GHG emissions were predominantly influenced by weather (precipitation) and crop and irrigation management. The influence of air temperature and floodwater heights on GHG emissions had high degree of variability among years and fields. These findings demonstrate that the use of multiyear GHG emission datasets could better capture variability of GHG emissions associated with rice production and could improve field verification of GHG emission models and scaling factors for commercial rice farms.

Congenital cutaneous Langerhans cell histiocytosis and cutaneous mastocytoma in a child.

Langerhans cell histiocytosis and mastocytoma are clonal disorders of bone-marrow-derived cells, most commonly seen in the pediatric age. Infiltration of mast cells and Langerhans cells in the same lesion has been published before, but, to our knowledge, this is the first time that the occurrence of two mastocytomas and Langerhans cell histiocytosis is reported. It could be hypothesized that both clonal disorders of bone-marrow-derived cells could have a common origin.

Effect of fertilising with pig slurry and chicken manure on GHG emissions from Mediterranean paddies.

Soil fertilisation affects greenhouse gas emissions. The objective of this study was to compare the effect of different fertilisation strategies on N2O, CH4 emissions and on ecosystem respiration (CO2 emissions), during different periods of rice cultivation (rice crop, postharvest period, and seedling) under Mediterranean climate. Emissions were quantified weekly by the photoacoustic technique at two sites. At Site 1 (2011 and 2012), background treatments were 2 doses of chicken manure (CM): 90 and 170kgNH4(+)-Nha(-1) (CM-90, CM-170), urea (U, 150kgNha(-1)) and no-N (control). Fifty kilogram N ha(-1) ammonium sulphate (AS) were topdress applied to all of them. At Site 2 (2012), background treatments were 2 doses of pig slurry (PS): 91 and 152kgNH4(+)-Nha(-1) (PS-91, PS-152) and ammonium sulphate (AS) at 120kgNH4(+)-Nha(-1) and no-N (control). Sixty kilogram NH4(+)-Nha(-1) as AS were topdress applied to AS and PS-91. During seedling, global warming potential (GWP) was ~3.5-17% of that of the whole rice crop for the CM treatments. The postharvest period was a net sink for CH4, and CO2 emissions only increased for the CM-170 treatment (up to 2MgCO2ha(-1)). The GWP of the entire rice crop reached 17Mg CO2-eqha(-1) for U, and was 14 for CM-170, and 37 for CM-90. The application of PS at agronomic doses (~170kgNha(-1)) allowed high yields (~7.4Mgha(-1)), the control of GWP (~6.5MgCO2-eqha(-1)), and a 13% reduction in greenhouse gas intensity (GHGI) to 0.89kgCO2-eqkg(-1) when compared to AS (1.02kgCO2-eqkg(-1)).

Sensibilidad de listeria monocytogenes frente al fosfato trisódico in vitro / Sensitivity of Listeria monocytogenes to trisodium fosfate in vitro

La carne de pollo presenta un elevado grado de contaminación superficial con microorganismos patógenos para el hombre y alterantes. Con el objeto de reducir dicha contaminación, desde 1992, el fosfato trisódico dodecahidrato (Na3PO4.12H2O) se está empleando en los mataderos de aves de Estados Unidos como un procedimiento de descontaminación. El efecto antimicrobiano de esta sal ha sido sobradamente demostrado frente a algunos microorganismos (fundamentalmente Gram negativos). No obstante, los datos publicados hasta el momento no son concluyentes por lo que se refiere a L. monocytogenes. Este estudio se llevó a cabo para evaluar la sensibilidad de 21 cepas de L. monocytogenes frente al fosfato trisódico in vitro. Para estandarizar la sensibilidad frente al fosfato trisódico utilizamos la concentración mínima inhibitoria, que se consideró como la menor concentración de la sal con la que la absorbancia (al cabo de 24 horas de incubación) no superó el valor 'umbral', que fue definido como el valor medio de las absorbancias de los blancos más tres desviaciones estándar. Los valores de las concentraciones mínimas inhibitorias (1,58-1,68 por ciento) fueron muy similares para las cepas de L. monocytogenes estudiadas. No encontramos ninguna relación entre el valor de la concentración mínima inhibitoria y la procedencia de las cepas (AU)