Aboveground biomass equations for sustainable production of fuelwood in a native dry tropical afro-montane forest of Ethiopia

International audienceAbstractKey messageBiomass equations are presented for five tree species growing in a natural forest in Ethiopia. Fitted models showed more accurate estimations than published generalized models for this dry tropical forest.ContextBiomass equations are needed to correctly quantify harvestable stock and biomass for sustainability efforts in forest management, but this kind of information is scarce in Ethiopia.AimsThis study sought to develop biomass models for five of the most common native tree species in the Chilimo dry afro-montane mixed forest in the central highlands of Ethiopia: Allophyllus abyssinicus, Olea europaea ssp. cuspidata, Olinia rochetiana, Rhus glutinosa, and Scolopia theifolia. Comparison with generalized models was intended to show the greater accuracy of the specific models.MethodsA total of 90 trees from different diameter classes were selected, felled, and divided into different biomass compartments. Biomass equation models were fitted using joint-generalized least squares regression to ensure the additivity property between the biomass compartments and total biomass.ResultsThese were the first models developed for these species in African tropical forests. Models were including diameter at breast height and total height as independent variables, obtaining more accurate biomass estimations using these models than from generalized models.ConclusionFitted models are reliable for estimating aboveground biomass in the Chilimo forest and for more general application in similar forest types. Model applicability for biomass or carbon estimation is high within forest inventory data contexts

Type Ia Supernova Scenarios and the Hubble Sequence

The dependence of the Type Ia supernova (SN Ia) rate on galaxy type is examined for three currently proposed scenarios: merging of a Chandrasekhar--mass CO white dwarf (WD) with a CO WD companion, explosion of a sub--Chandrasekhar mass CO WD induced by accretion of material from a He star companion, and explosion of a sub--Chandrasekhar CO WD in a symbiotic system. The variation of the SNe Ia rate and explosion characteristics with time is derived, and its correlation with parent population age and galaxy redshift is discussed. Among current scenarios, CO + He star systems should be absent from E galaxies. Explosion of CO WDs in symbiotic systems could account for the SNe Ia rate in these galaxies. The same might be true for the CO + CO WD scenario, depending on the value of the common envelope parameter. A testable prediction of the sub--Chandrasekhar WD model is that the average brightness and kinetic energy of the SN Ia events should increase with redshift for a given Hubble type. Also for this scenario, going along the Hubble sequence from E to Sc galaxies SNe Ia events should be brighter on average and should show larger mean velocities of the ejecta. The observational correlations strongly suggest that the characteristics of the SNe Ia explosion are linked to parent population age. The scenario in which WDs with masses below the Chandrasekhar mass explode appears the most promising one to explain the observed variation of the SN Ia rate with galaxy type together with the luminosity--expansion velocity trend.Comment: 16 pages uuencoded compressed Postscript, 2 figures included. ApJ Letters, in pres

Pseudohyphal growth of the emerging pathogen Candida auris is triggered by genotoxic stress through the S phase checkpoint

We are grateful to Arunaloke Chakrabarti, Anuradha Chowdhary, Elizabeth Johnson (PHE), Takashi Kubota, and Shawn Lockhart (CDC) for providing strains. We thank Fei Long for skillful technical assistance. Flow cytometry was performed at the Iain Fraser Cytometry Centre (IFCC), University of Aberdeen (Raif Yuecel). Microscopy was done at the Microscopy & Histology Facility, University of Aberdeen (Kevin S. Mackenzie). This work was supported by a Wellcome Trust Seed Award to AL [grant number 212524/Z/18/Z], and the Medical Research Council (MRC) Centre for Medical Mycology at the University of Exeter [grant numbers MR/P501955/1, MR/N006364/1].Peer reviewedPreprin

Muerte de un lince ibérico. Establecimiento de la causa y la autoría

Las ciencias forenses se aplican desde hace poco tiempo como herramientas en las investigaciones de delitos contra el medio ambiente. En este trabajo se expone un caso pionero en cuanto a la utilización de estas técnicas en un caso de un delit o contra la fauna silvestre. La investigación se inicia tras la apari ción de un lince ibérico muerto en el interior de una finca, donde se encontraron también varios pollos supuestamente utilizados como cebos envenenados y otro cadáver, el de un zorro. El lince ib érico es uno de los mamíferos más amenazados del planeta. Se llevaron a cabo distintos análisis a partir de la necropsia de los cadáveres en el Centro de Análisis y Diagnóstico de la Fauna Silvestre (CAD), el laboratorio de referencia para la fauna silvestre pertene ciente a la Junta de Andalucía. Los resultados fuer on concluyentes, ambas muertes se produjeron como consecuencia de la ingestión de cebos envenenados con un plaguicida extremadamente tóxico, el aldicarb. También se encontró esta sustancia en los pollos recogidos en el interior de la finca. Con el fin de e stablecer la culpabilidad de los propietarios de la finca, que negaron tener nada que ver con las muertes y la colocación de los cebos, se utilizó una herramienta novedosa en este tipo de investigaciones, la genética forens e. En base a los resultados se co nsiguió establecer una relación de parentesco entre los pollos utilizados como cebos envenenados y los pollos propiedad reconocida de los sospechosos, que permitió demostrar que todos tenían el mismo origen. Gracias al trabajo conjunto y coordinado durante toda la investigación y el informe pericial elaborado por el laboratorio del CAD, la Consejería de Medio Ambiente y Organización del Territorio de la Junta de Andalucía consiguió una sentencia ejemplar contra los envenenador es.The application of forensic science as a research tool to resolve crimes against the environment is relatively rec ent. To our knowledge this is the first instance in which the forensic genetic have been used as a definitive evidence to find out guilty in crimes against the wildlife. Our research starts when an Iberian lynx was found dead into a farm; very close to sev eral chickens used as poisoned baits and a fox carcass. Iberian lynx is one of the most endangered mammals in the planet. A comprehensive investigation from the carcasses was performed in the Analysis and Diagnostic Center for Wildlife in Andalucia (CAD), the reference laboratory for wildlife of the Andalusian Government (Spain). The results determined that the deaths occurred as a result of ingestion o f baits poisoned with an extremely toxic pesticide, aldicarb. This substance was also found in chickens ga thered inside the farm. In order to establish the guilt of the owners of the farm, who refused to be related to the deaths and the placement of the b aits, an innovative tool was used in this kind of research, the forensic genetic. Based on the results we got, we established a relationship between the chickens used as poisoned baits and the chickens from the farmer, all of them had the same origin. Thanks to the coordinated actuation during the complete investigation and the official report by the CAD labor atory used in the trial, the Ministry of Environmental and Territorial Organization got an exemplary sentence against the poisoners

Efecto de la temperatura de incubación en la susceptibilidad del género Bacillus frente a antibióticos

Se ha estudiado la susceptibilidad de 54 cepas de Bacillus, incluídas en 23 especies, frente a 17 antibióticos pertenecientes a diversos grupos, mediante la técnica clásica de antibiograma por difusión en agar, incubando las placas a 37°C y a 22°C respectivamente. En el 86 %de los casos estudiados, la susceptibilidad fue mayor a 22°C que a 37°C, y solamente en el 1 % ocurrió lo contrario. La influencia de la temperatura fue similar sobre cepas mesófIlas, psicrófIlas y termófIlas.The classical agar diffusion method was applied to study the sensitivity of 54 strains included in 23 species of genus Bacillus, against 17 antibiotics different groups. Sensitivity test were belonging to performed at 22°C and at 37°C. Bacterial sensitivity at 22°C was larger than at 37°C in most of the cases (86 %), where as the contrary was infrequent (l % ). Sensitivity of mesophile, thermophile, and psychrophile strains were equalIy influenced

Efecto de la temperatura de incubación en la susceptibilidad del género Bacillus frente a antibióticos

The classical agar diffusion method was applied to study the sensitivity of 54 strains included in 23 species of genus Bacillus, against 17 antibiotics different groups. Sensitivity test were belonging to performed at 22°C and at 37°C. Bacterial sensitivity at 22°C was larger than at 37°C in most of the cases (86 %), whereas the contrary was infrequent (1 %). Sensitivity of mesophile, thermophile, and psychrophile strains were equalIy influenced.Se ha estudiado la susceptibilidad de 54 cepas de Bacillus, incluídas en 23 especies, frente a 17 antibióticos pertenecientes a diversos grupos, mediante la técnica clásica de antibiograma por difusión en agar, incubando las placas a 37°C y a 22°C respectivamente. En el 86 %de los casos estudiados, la susceptibilidad fue mayor a 22°C que a 37°C, y solamente en el 1 % ocurrió lo contrario. La influencia de la temperatura fue similar sobre cepas mesófIlas, psicrófIlas y termófIlas

Posible interés taxonómico de las pruebas de sensibilidad frente a antibióticos en el género Bacillus

The study of bacterial sensitivity to antibiotics has been found useful to taxonomic characterization of species of the genus Bacillus. Sensitivity to rifampicin is proposed as an interesting test, since it characterized two groups of species. Chloramphenicol, tetracycline, streptomycin, gentarnicin, kanamycin, fusidic acid, and novobiocin were also considered useful to the species identification. On the other han, β-lactam antribiotics were not apporopiated for this aim, because of the unpredictable appearance of intraspecific resistances. A characteristic pattem of sensitivity to most antibiotics was shown by B. psychrophilus.El estudio de la susceptibilidad frente a antibióticos se ha considerado útil en la caracterización taxonómica de algunas especies del género Bacillus. La sensibilidad a la rifampicina puede proponerse como prueba de interés, pues diferencia dos grandes grupos de especies según el grado de inhibición mostrado. Otros antibióticos de utilidad en la diferenciación de especies fueron: cloranfenicol, tetraciclina, estreptomicina, gentamicina, kanamicina, ácido fusídico y novobiocina. En general, los β-lactámicos no resultaron apropiados para la identificación, por la irregular distribución de resistencias intraespecíficas. La especie B. psychrophilus exhibió un comportamiento diferenciado del de otras especies frente a la mayoría de los antibióticos probados

The controllability of a monetary aggregate in EMU

La consideracion de un agregado monetario como objetivo intermedio de la politica monetaria exige que esa definicion de liquidez mantenga una relacion de estabilidad con el objetivo final y que su evolucion pueda ser controlada por parte del banco central. Este documento analiza esta segunda cuestion, centrandose en las posibilidades que tendria el Banco Central Europeo de controlar efectivamente un agregado monetario si decidiera considerarlo como objetivo intermedio. En el trabajo se revisan los mecanismos a traves de los cuales la politica monetaria puede controlar la evolucion de la cantidad de dinero, y se examinan las propiedades empiricas de la demanda de dinero en la Union Monetaria Europea (UME) y en un pais, como Alemania, en el que se han venido fijando objetivos en terminos de un agregado monetario. El documento pone de manifiesto que las condiciones para ejercer un control adecuado de la cantidad de dinero en la UME son notablemente mas desfavorables de lo que resultan en Alemania. (ac) (jle) (em) (jp) (mac

Adherencia bacteriana a linfocitos humanos y murinos

We have studied the capacity for a selective adherence to different human and murine lymphoid subpopulation of bacterial strains belonging to different genera and species. The strains of the genus Bacillus normally have a great capacity to bind to the murine lumphoid surfaces. Other strains with interesting adherence properties are Staphylococcus epidermidis, S. aurcus, Yersinia enterocolitica and Sporosarcina halophila. In the assay of adherence to human lumphocytes only Y. enterocolitica and S. halophila show binding capacity although in any one of cases in selective way.Hemos estudiado la capacidad de adherencia selectiva a distintas subpoblaciones linfocitarias humanas y murinas de diferentes cepas bacterianas pertenecientes a distintos géneros y especies. Las cepas pertenecientes al género Bacillus tienen, en general gran capacidad de unión a la superficie linfocitaria murina. Otras especies que presentan interesantes propiedades de adherencia son: Staphylococcus epidermidis, S. aurcus, Yersinia enterocolitica y Sporosarcina halophila. En el ensayo de adherencia a linfocitos humanos solo Y. enterocolitica y S. halophila se unen a ellos, aunque en ninguno de los casos de forma selectiva

A methodology for coupling DGGE and mathematical modelling : application in bio-hydrogen production

Molecular biology techniques provide valuable information in terms of microbial dynamic and evolution. DGGE analysis is one of the most popular methods, which has been used in bioprocess assessment. A novel procedure that combines common experimental measurements, DGGE and image analysis is presented as a new methodology for preliminary assessment. In this study, the methodology was applied as an example to the start up of a hydrogen bioreactor, in order to have a preliminary estimation of the actual concentration of the different microbial species. The obtained results are used for determining the kinetic parameter by using a simple mathematical model focusing on species dynamic