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The search for microfossils in the geological record has been a long-term challenge. Part of the problem comes from the difficulty of identifying such microfossils unambiguously, since they can be morphologically confused with abiotic biomorphs. One route to improve our ability to correctly identify microfossils involves studying fossilization processes affecting bacteria in modern settings. We studied the initial stages of fossilization of cyanobacterial cells in modern microbialites from Lake Alchichica (Mexico), a Mg-rich hyperalkaline crater lake (pH 8.9) hosting currently growing stromatolites composed of aragonite [CaCO3] and hydromagnesite [Mg5(CO3)4(OH)2 · 4(H2O)]. Most of the biomass associated with the microbialites is composed of cyanobacteria. Scanning electron microscopy analyses coupled with confocal laser scanning microscopy observations were conducted to co-localize cyanobacterial cells and associated minerals. These observations showed that cyanobacterial cells affiliated with the order Pleurocapsales become specifically encrusted within aragonite with an apparent preservation of cell morphology. Encrustation gradients from non-encrusted to totally encrusted cells spanning distances of a few hundred micrometers were observed. Cells exhibiting increased levels of encrustation along this gradient were studied down to the nm scale using a combination of focused ion beam (FIB) milling, transmission electron microscopy (TEM) and scanning transmission x-ray microscopy (STXM) at the C, O and N K-edges. Two different types of aragonite crystals were observed: one type was composed of needle-shaped nano-crystals growing outward from the cell body with a crystallographic orientation perpendicular to the cell wall, and another type was composed of larger crystals that progressively filled the cell interior. Exopolymeric substances (EPS), initially co-localized with the cells, decreased in concentration and dispersed away from the cells while crystal growth occurred. As encrustation developed, EPS progressively disappeared, but remaining EPS showed the same spectroscopic signature. In the most advanced stages of fossilization, only the textural organization of the two types of aragonite recorded the initial cell morphology and spatial distribution.

The comb is an ornament involved in signalling condition in domestic fowl. We hypothesised that comb size, comb shape complexity (i.e., rugosity, the comb perimeter jaggedness), and comb laterality of laying hens would be influenced by the degree of environmental enrichment experienced during juvenile development in the form of resource choice. We conducted a 2 × 2 factorial crossover experiment with pullets reared in pens containing four perches of equal length and four litter areas of equal size. Pullets were exposed to a single choice vs multiple choices of perch and litter types (i.e., all the same vs all different) during Weeks 1–4 (Period 1) and/or Weeks 5–15 (Period 2) of rearing (n = 4 pens/treatment combination) prior to transfer to standard adult laying pens for Weeks 16–27 (Period 3). In Week 27, combs were photographed, and comb laterality (hanging on left or right side) was noted. Using a custom-made image analysis programme, we captured comb area (mm2), perimeter length (mm), and rugosity ((perimeter length – horizontal length) / horizontal length) from comb photographs of 6–7 randomly selected hens/pen. We predicted that hens reared in the multi-choice environment during Periods 1 and 2 would have larger, more complex, and left-side-biased combs than those in the other treatment groups, reflecting lower allostatic load. The predicted comb side bias was based on a possible bias in head posture/movements associated with greater right eye/ear use and left-brain hemispheric dominance. Contrary to our predictions, we detected an overall right-side bias in comb laterality, and no associations between resource choice treatment in Period 1 or Period 2 and comb area, perimeter length, rugosity, or laterality of the adult hens. Thus, variation in allostatic load resulting from the rearing treatments was insufficient to modify the trajectory of comb morphological development, possibly due to a ceiling effect when comparing environmental treatments on the positive end of the welfare spectrum. We found that left-lopping combs had shorter perimeters than right-lopping combs. However, among hens with left-lopping combs, those with larger combs were heavier and had less feather damage, while among hens with right-lopping combs, those with longer-perimeter combs were heavier and tended to have less comb damage. In conclusion, comb characteristics were related to physical condition at the individual level but did not serve as sensitive integrated indicators of hen welfare in response to basic vs enhanced resource choice during rearing.

ABSTRACT: At 17 wk of age, 1,800 Lohman brown hens were housed in 8 pens of an experimental aviary system, specifically set up for the purposes of the present study, and kept until 26 wk without or with nest lighting (lights inside the nest 1.5 h before the lighting of the installation) for training in the nest use. Then, at 27 wk, 4 combinations of nest curtains were adopted to evaluate the effects on hens’ distribution, that is, nests with red (RR) or yellow (YY) curtains at all tiers; nests with red and yellow curtains at the first and second tier, respectively (RY); or nests with yellow and red curtains at the first and second tier, respectively (YR). The use of enlightened compared to dark nests at housing increased the oviposition rate (P < 0.001) and decreased the rate of broken (P < 0.001) and dirty eggs (P < 0.05) from 27 to 45 wk, while increasing the rate of eggs laid inside the nests (P < 0.001). The presence of yellow nest curtains increased the rate of hens on the floor in pens YY and YR compared to pens RR and RY (35.3 and 35.5% vs. 34.1 and 33.3%, respectively; P = 0.05) and the rate of floor eggs in pens YR (2.23% vs. 1.63 and 1.65% in pens RR and RY; P < 0.05). In pens RY, a higher rate of eggs was always found on the second tier compared to the first one with the most inhomogeneous distribution compared to pens RR, YY, and YR (+10.8 vs. +3.4, +1.9, and +4.6 percentage points of eggs laid on the second tier compared to the first one, respectively). In conclusion, nest lighting at housing trained hens to the use of nests while improving egg production in terms of quantity and quality. The use of yellow curtains on nests moved hens between the different levels of the aviary but this was not associated with an increased nest use for laying.

The enhancement of biogas and CH4 yields through anaerobic co-digestion (co-AD) of the pre-hydrolysed Organic Fraction of Municipal Solid Waste (hOFMSW) and Maize Cob Waste (MCW) was tested in a lab- scale thermophilic anaerobic reactor. Before the co-AD, MCW was chemically pre-treated with H2O2 at room temperature in alkaline conditions (10 % MCW wMCW/ valkaline water) with 4 hours contact time, at a ratio of 0.5 wH2O2/wMCW. This pre-treatment is the last of a set of pre-treatments catalysed by H2O2 already tested by the authors. The anaerobic reactor was initially fed with hOFMSW obtained from the hydrolysis tank of an industrial AD plant. The hOFMSW was co-digested with the pre-treated MCW and then with non-pre-treated MCW. The co-AD of hOFMSW with pre-treated MCW (CASE 1) increased the biogas yield by 65 % and CH4 yield by 48 %, when compared to the results obtained with the standalone hOFMSW, while the co-digestion of hOFMSW with non-pre-treated MCW (CASE 2) increased biogas and CH4 yields by 84 % and 57 %, respectively. Despite of higher yields, the Low Heating value (LHV) and daily energy content (LHV * Volume of biogas per day) in biogas stream, obtained in CASE 2 were on average 4 % and 1% lower, respectively than in the biogas stream obtained with CASE 1. These results showed that the pre-treatment is recommended before submitting MCW to co-AD and the chemical pre-treatment of MCW with H2O2, at room temperature, is a promising low-cost way to valorise MCW through co-AD.

Resumen: La utilización de herramientas que permitan detectar problemas de programación es de utilidad tanto para el docente, el cual puede probar de una forma más exhaustiva las prácticas entregadas, como para el discente, el cual puede utilizar dichas herramientas. En muchos casos, existen herramientas previas utilizadas en el desarrollo software, que pueden ser adaptadas para ser utilizadas en un entorno formativo. Este trabajo aporta la integración de una herramienta de validación formal de sistemas concurrentes Java, la cual garantiza la no existencia de defectos como son el abrazo mortal y las condiciones de carrera, en un entorno Web abierto. Más concretamente, la herramienta que se ha escogido es denominada JPF (Java Path Finder) y se la ha dotado de interfaces dentro de un servidor Java EE (Enterprise Edition), lo que facilita la utilización de servicios propios de la plataforma Java EE y la interoperabilidad entre estos con el módulo diseñado. El artículo trata aspectos tecnológicos derivados de dicha integración como son el diseño de una arquitectura que da soporte a la validación vía web. También detalla una serie de experimentos relativos al rendimiento de la plataforma realizados sobre un curso real, lo que permite medir costes computacionales y su utilidad en la evaluación Abstract: Tools that allow detecting programming faults are useful for both docents, who may test submitted exercises, and students, who may use these tools in advance. In this article the authors develop one tool for detecting failures in applications. In many cases there are previous tools that may be readapted to be used in an educational scope. This article integrates of one of these tools, which avoids code with dead-locks and race-conditions, into the Internet. The tool integrated is JPF (Java Path Finder) and it is accessed from a Java EE web frontend which carries out the exercise assessment. The article deals with the definition of the module and its evaluation on a realistic scenario. The results show that many assignments may benefit from the output of the tool. Palabras clave: Herramientas, Informática Industrial, Validación Formal, Sistemas Concurrentes, Educación, Java, Keywords: Tools, Industrial Informatics, Formal Validation, Concurrent Systems, Education, Java

RESUMO: O Sarcoma da Artéria Pulmonar é um tumor raro, apresentando-se com sinais e sintomas inespecíficos, simulando por vezes o Tromboembolismo Pulmonar (TEP), o que torna o seu diagnóstico difícil e tardio.A este propósito os autores apresentam um caso de um homem de 59 anos, ex-fumador, internado por dispneia de esforço, toracalgia e sintomas gerais.Portador de uma radiografia e TAC torácicas, ambas evidenciando imagens sugestivas de Trombose da Artéria Pulmonar Direita.Analiticamente e antes de qualquer terapêutica: Inibidor Lúpico â e anticardiolipina IgM +.Presumido diagnóstico inicial de TEP crónico em doente com provável Síndroma de Hipercoaguabilidade, iniciou terapêutica hipocoagulante, com melhoria.Reinternado 2 meses após alta por agravamento clínico e radiológico. Proposto e aceite para Tromboendarterectomia Pulmonar, sob circulação extracorporal e paragem cardiocirculatória em hipotermia profunda (18 ºC). Durante a cirurgia constatou-se a presença de «mega-artérias pulmonares» preenchidas por massa trombosada que se estendia à s ramificações arteriais segmentares. Após a exérese dessa massa houve necessidade de realizar Pneumectomia direita por hemorragia progressiva incontrolável.Veio a falecer ao 7.º dia de pós-operatório, por ARDS em pulmão único.Resultado Anatomopatológico: Sarcoma da Artéria Pulmonar com Metastização Pulmonar e Pleural.REV PORT PNEUMOL IX (1): 41-51 ABSTRACT: Primary Pulmonary Artery Sarcoma is a rare entity, which shares some clinical features with Thromboembolic Pulmonary Disease (TEPD), complicating differential diagnosis.The authors report a Clinical Case of a Primary Pulmonary Artery Sarcoma in a 59 years old man, admitted with a history of dyspnoea on exertion, chest pain and general symptoms. Chest X-ray, Computed Tomography Scan, Angiographies and Magnetic Resonance Imaging suggested TEPD.Blood Analysis performed before anticoagulation therapy: Lupus Anticoagulant - and Ig M Anticardiolipin+.Our presumptive initial diagnosis was TEPD in a patient with a hypercoagulable state.Intravenous heparin was started, with some clinical improvement but 2 months later he was readmitted, due to clinical and radiological deterioration. Pulmonary Thromboendarterectomy was considered but a right pneumonectomy was necessary because of bleeding. He died of ARDS in a single lung in the 7 th day after surgery. Pathology revealed pulmonary artery sarcoma with pulmonary and pleural metastases.REV PORT PNEUMOL IX (1): 41-51 Palavras-chave: Sarcoma da Artéria Pulmonar, Tumores Vasculares, Key-words: Pulmonary Artery Sarcoma, Vascular Tumour

El presente trabajo tiene como objetivo brindar algunas consideraciones para elevar la eficiencia del proceso de transformación mecánica en los aserraderos a partir de la utilización de la herramienta matemática que permitirá el perfeccionamiento del aserrado de la madera. Con la reducción del corte de apertura del asierre, se eleva la eficiencia de la conversión mecánica de la madera en los aserraderos hasta un rendimiento volumétrico total entre 4.7 y 8.3 %, lo cual posibilita una mejor utilización de la madera como materia prima. Por otra parte; se desarrolla un procedimiento matemático que permite definir la amplitud del corte de apertura en las trozas, facilitando una mayor utilización de la madera en la zona cercana a la corteza.

Hibiscus elatus Sw. (majagua) es una especie nativa de Cuba, incluida en los planes de reforestación del país por su importancia económica, ecológica y su condición de ser una madera preciosa. En el trabajo se describe el comportamiento en vivero del crecimiento en altura de la especie, cultivada en contenedores. Se utilizaron cuatro tipos de sustratos, que fueron los siguientes: S1- Turba (40 %), humus de lombriz (40 %) y corteza de pino compostada (20 %); S2- Estiércol de caballo (45 %), composta (40 %), y humus de lombriz (15 %); S3- Humus de lombriz (30 %), composta (25 %), turba (25 %), y estiércol de caballo (20 %); S4- Testigo, consistente en suelo proveniente de una plantación de la especie. A través del análisis de regresión se probaron nueve modelos matemáticos del tipo y = f (x), polinómicos, exponenciales y logarítmicos. De acuerdo con el coeficiente de determinación obtenido, del análisis de residuos y la validación de los modelos, se comprobó que la función que mejor representa el crecimiento en altura de Hibiscus elatus Sw., para los sustratos estudiados fue b t y b e 1 = 0 + .

Diez muestras de carbón bituminoso, presentando diferentes niveles de meteorización, fueron colectadas a diferentes profundidades de dos minas subterráneas ubicadas en la localidad de Hato de la Virgen, Estado Táchira, Venezuela: la galería G-ll, donde se explota el manto 20, con un contenido de azufre ≻ 5 %; y la galería G-24, donde está presente el manto 24, cuya abundancia en este elemento no supera el 1,5 %. El objetivo del presente trabajo es evaluar el efecto del azufre en la extensión de la meteorización del carbón. Con fines comparativos, se cuenta con las respectivas muestras totalmente frescas, provenientes de núcleos de perforación. Los carbones fueron sometidos a los siguientes análisis: inmediatos (humedad, materia volátil, carbono fijo, cenizas, poder calórico), Indice de hinchamiento libre (FSI), análisis elemental (C, H, N, O), azufre total y sus formas (pirítico, sulfático y orgánico), y composición mayoritaria de las cenizas (Si, Al, Ca, Mg, Mn, Fe, K, Na, Cl, P). Adicionalmente, se obtuvieron sus espectros de infrarrojo, en el modo de Transformadas de Fourier. Sólo las muestras procedentes de los núcleos de perforación son totalmente frescas; las muestras colectadas dentro de las galerías manifiestan diferentes niveles de oxidación, detectada tanto por parámetros químicos (humedad, poder calórico, composición elemental y de las cenizas) como por espectroscopia de infrarrojo (aparición de la banda de carbonilo, disminución de la absorción propia de estiramiento del enlace C-H). La presencia de azufre en alta proporción no modifica de manera apreciable ni el estilo ni la extensión de la oxidación de la matriz orgánica del carbón. Sin embargo, el azufre sí es responsable de variaciones importantes en el estilo de alteración de la matriz inorgánica, modificando el esquema de lixiviación de algunos elementos (principalmente Fe, y en menor extensión Si, P, K), que son removidos preferentemente, e inmovilizando otros (Ca, Mg, Mn) mediante precipitación como sulfatos insolubles.

The SuperCam instrument suite onboard the Mars 2020 Perseverance rover uses the laser-induced breakdown spectroscopy (LIBS) technique to determine the elemental composition of rocks and soils of the Mars surface. It is associated with a microphone to retrieve the physical properties of the ablated targets when listening to the laser-induced acoustic signal. In this study, we report the monitoring of laser-induced mineral phase transitions in acoustic data. Sound data recorded during the laser ablation of hematite, goethite and diamond showed a sharp increase of the acoustic signal amplitude over the first laser shots. Analyses of the laser-induced craters with Raman spectroscopy and scanning electron microscopy indicate that both hematite and goethite have been transformed into magnetite and that diamond has been transformed into amorphous-like carbon over the first laser shots. It is shown that these transitions are the root cause of the increase in acoustic signal, likely due to a change in target's physical properties as the material is transformed. These results give insights into the influence of the target's optical and thermal properties over the acoustic signal. But most importantly, in the context of the Mars surface exploration with SuperCam, as this behavior occurs only for specific phases, it demonstrates that the microphone data may help discriminating mineral phases whereas LIBS data only have limited capabilities., (© 2021. The Author(s).)

By the end of 2018, 42 years after the landing of the two Viking seismometers on Mars, InSight will deploy onto Mars' surface the SEIS ( S eismic E xperiment for I nternal S tructure) instrument; a six-axes seismometer equipped with both a long-period three-axes Very Broad Band (VBB) instrument and a three-axes short-period (SP) instrument. These six sensors will cover a broad range of the seismic bandwidth, from 0.01 Hz to 50 Hz, with possible extension to longer periods. Data will be transmitted in the form of three continuous VBB components at 2 sample per second (sps), an estimation of the short period energy content from the SP at 1 sps and a continuous compound VBB/SP vertical axis at 10 sps. The continuous streams will be augmented by requested event data with sample rates from 20 to 100 sps. SEIS will improve upon the existing resolution of Viking's Mars seismic monitoring by a factor of ∼ 2500 at 1 Hz and ∼ 200 000 at 0.1 Hz. An additional major improvement is that, contrary to Viking, the seismometers will be deployed via a robotic arm directly onto Mars' surface and will be protected against temperature and wind by highly efficient thermal and wind shielding. Based on existing knowledge of Mars, it is reasonable to infer a moment magnitude detection threshold of M w ∼ 3 at 40 ∘ epicentral distance and a potential to detect several tens of quakes and about five impacts per year. In this paper, we first describe the science goals of the experiment and the rationale used to define its requirements. We then provide a detailed description of the hardware, from the sensors to the deployment system and associated performance, including transfer functions of the seismic sensors and temperature sensors. We conclude by describing the experiment ground segment, including data processing services, outreach and education networks and provide a description of the format to be used for future data distribution., Electronic Supplementary Material: The online version of this article (10.1007/s11214-018-0574-6) contains supplementary material, which is available to authorized users.

Micrometer-sized spherical and rod-shaped forms have been reported in many phosphorites and often interpreted as microbes fossilized by apatite, based on their morphologic resemblance with modern bacteria inferred by scanning electron microscopy (SEM) observations. This interpretation supports models involving bacteria in the formation of phosphorites. Here, we studied a phosphatic coprolite of Paleocene age originating from the Ouled Abdoun phosphate basin (Morocco) down to the nanometer-scale using focused ion beam milling, transmission electron microscopy (TEM), and scanning transmission x-ray microscopy (STXM) coupled with x-ray absorption near-edge structure spectroscopy (XANES). The coprolite, exclusively composed of francolite (a carbonate-fluroapatite), is formed by the accumulation of spherical objects, delimited by a thin envelope, and whose apparent diameters are between 0.5 and 3 μm. The envelope of the spheres is composed of a continuous crown dense to electrons, which measures 20-40 nm in thickness. It is surrounded by two thinner layers that are more porous and transparent to electrons and enriched in organic carbon. The observed spherical objects are very similar with bacteria encrusting in hydroxyapatite as observed in laboratory experiments. We suggest that they are Gram-negative bacteria fossilized by francolite, the precipitation of which started within the periplasm of the cells. We discuss the role of bacteria in the fossilization mechanism and propose that they could have played an active role in the formation of francolite. This study shows that ancient phosphorites can contain fossil biological subcellular structures as fine as a bacterial periplasm. Moreover, we demonstrate that while morphological information provided by SEM analyses is valuable, the use of additional nanoscale analyses is a powerful approach to help inferring the biogenicity of biomorphs found in phosphorites. A more systematic use of this approach could considerably improve our knowledge and understanding of the microfossils present in the geological record., (© 2012 Blackwell Publishing Ltd.)