Interest in the use of biochar from pyrolysis of biomass to sequester C and improve soil productivity has increased; however, variability in physical and chemical characteristics raises concerns ...about effects on soil processes. Of particular concern is the effect of biochar on soil N dynamics. The effect of biochar on N dynamics was evaluated in a Norfolk loamy sand with and without NH4NO3. High‐temperature (HT) (≥500°C) and low‐temperature (LT) (≤400°C) biochars from peanut hull (Arachis hypogaea L.), pecan shell (Carya illinoinensis Wangenh. K. Koch), poultry litter (Gallus gallus domesticus), and switchgrass (Panicum virgatum L.) and a fast pyrolysis hardwood biochar (450–600°C) were evaluated. Changes in inorganic, mineralizable, resistant, and recalcitrant N fractions were determined after a 127‐d incubation that included four leaching events. After 127 d, little evidence of increased inorganic N retention was found for any biochar treatments. The mineralizable N fraction did not increase, indicating that biochar addition did not stimulate microbial biomass. Decreases in the resistant N fraction were associated with the high pH and high ash biochars. Unidentified losses of N were observed with HT pecan shell, HT peanut hull, and HT and LT poultry litter biochars that had high pH and ash contents. Volatilization of N as NH3 in the presence of these biochars was confirmed in a separate short‐term laboratory experiment. The observed responses to different biochars illustrate the need to characterize biochar quality and match it to soil type and land use.
Soil amendments are used to improve soil quality, thereby enhancing plant growth and health. Efforts have been made to replace synthetic chemical enhancers. It is also preferable to not use natural ...products such as peat moss, the harvesting of which can be harmful to marine ecosystems. Viable replacements include worm castings, which can contribute beneficial microbes, as well as physicochemical amendments. Another potential soil amendment is the compost produced from sugarcane processing byproducts. While the texture of these two materials is not ideal for even dispersal onto fields, the addition of biochar improves the texture. Previous work demonstrated that blending them with biochar from sugarcane byproducts added physicochemical benefits, while not quantitatively reducing the microbial load, even after storage. Microbial populations of the blends in the present study were found to (1) contain taxonomic groups that contribute to plant health and (2) not contain human pathogens. Based on the quantitative and qualitative microbial analyses, it has been determined that 50% or less biochar in a blend will allow maintenance of beneficial microbes in stored samples.
ABSTRACT Moenkhausia melogramma is herein redescribed, based on the examination of the holotype plus additional specimens from the western Amazon basin in Brazil, Colombia, Peru, and Ecuador. ...Moenkhausia melogramma shares with M. collettii, M. conspicua, M. copei, M. venerei, and M. flava a broad dark longitudinal stripe across the eye, and a well-defined dark stripe on the anal-fin base. It can be promptly distinguished from these species by having two humeral blotches. Additionally, we provide comments on the putative relationships of Moenkhausia melogramma with the aforementioned congeners and the Hemigrammus lunatus species-group.
RESUMO Moenkhausia melogramma é redescrita com base no exame do holótipo e exemplares adicionais da bacia amazônica ocidental no Brasil, Colômbia, Peru e Equador. Moenkhausia melogramma compartilha com M. collettii, M. conspicua, M. copei, M. venerei e M. flava a presença de uma faixa larga longitudinal escura que atravessa os olhos e uma linha escura bem definida na base da nadadeira anal. Ela pode ser prontamente distinguida dessas espécies por ter duas manchas umerais. Adicionalmente, fornecemos comentários sobre as possíveis relações filogenéticas de Moenkhausia melogramma com as congêneres supramencionadas e com o grupo de espécies Hemigrammus lunatus.
ABSTRACT Introduction: the attraction of women by Surgery has always existed. Although Surgery has been considered a specialty for men, several women chose it, despite gender bias issues that have ...persisted over many years. Several obstacles have impacted the practice of women surgeons, leading them to abandon the profession, while others, perhaps bearers of a stronger spirit, managed to overcome them, and won. Objective: to assess the rates of perception of harassment against female surgeons as a cause of difficulty and negative feelings related to the specialty. Methods: we conducted a quantitative and qualitative (personal accounts) research through a questionnaire via Google Forms® sent to all women surgeons registered in the Brazilian College of Surgeons and in a WhatsApp women surgeons’ groups. The qualitative analysis was made with the Wordle® app. Results: from 821 questionnaires sent, we obtained 232 responses (28.2%). Harassment perception during training was 49.1% (n=114). From the women surgeons who perceived harassment, 56.1% reported having undergone different training than expected, with statistical significance (p<0.001). The question of having been treated differently due to being a woman also had an impact on harassment perception (77.2% harassed vs 47.5%; p<0.001). Physical (42.1% vs 6.8%) and emotional (92.1% vs 39.8%) threats were also different between groups. Conclusion: women surgeons still report great harassment perception, both moral and sexual, which impacts their feelings about the specialty.
RESUMO Introdução: a atração das mulheres pela Cirurgia sempre existiu. Embora a Cirurgia seja considerada especialidade para homens, várias mulheres a escolheram, apesar de questões de preconceito de gênero que têm se mantido ao longo de vários anos. Vários obstáculos têm impactado na prática das cirurgiãs, levando-as a abandonar a profissão, mas outras, talvez, as de espírito mais forte, conseguiram superá-los e venceram. Objetivo: avaliar a taxas de percepção de assédio contra cirurgiãs como causa de dificuldade e sentimentos negativos relacionados com a especialidade. Método: pesquisa, quantitativa e qualitativa (relatos pessoais), realizada por meio de questionário via Google Forms® enviado para todas as cirurgiãs registradas no Colégio Brasileiro de Cirurgiões e em grupo WhatsApp de cirurgiãs. A análise qualitativa foi feita com o aplicativo Wordle®. Resultados: Foram enviados 821 questionários e obtidas 232 respostas (28,2%). A percepção de assédio durante o treinamento foi de 49.1% (n=114). As cirurgiãs com percepção de assédio foram estatisticamente aquelas que reportaram ter tido treinamento diferente do que ansiavam (56,1%) (p<0,001). O quesito tratamento distinto por ser mulher também impactou na percepção do assédio (77,2% assediadas vs 47,5%; p<0,001). Ameaça física (42,1% vs 6,8%) e emocional (92,1% vs 39,8%) também foram distintas entre os grupos. Conclusão: cirurgiãs ainda reportam grande percepção de assédio moral e sexual, o que impacta na forma de encarar a profissão.
The infrared thermography has been successfully applied as a tool for high resolution imaging in different hydrological studies. This exploratory experimental study aimed at evaluating the ...possibility of using infrared thermography to determine the diameter of raindrops. Rain samples are collected on a pre-heated acrylic board, which is exposed to rain during an instant, and thermograms are recorded. The area of the thermal stains ("signatures" of the raindrops) emerging on the board is measured and converted to drop diameters, applying a calibration equation. Diameters of natural raindrops estimated using this technique were compared with laser disdrometer measurements; the Nash-Sutcliffe efficiency coefficient was used for evaluating the match between the resulting histograms of drop size distribution. Results confirm the usefulness of this simple technique for sizing and counting raindrops, although it is unsatisfactory in light rain or drizzle.
Macropores and water flow in soils and substrates are complex and are related to topics like preferential flow, nonequilibrium flow, and dual-continuum. Hence, the quantification of the number of ...macropores and the determination of their geometry are expected to provide a better understanding on the effects of pores on the soil’s physical and hydraulic properties. This exploratory study aimed at evaluating the potential of using infrared thermography for mapping macroporosity at the soil surface and estimating the number and size of such macropores. The presented technique was applied to a small scale study (laboratory soil flume).
A new species of Moenkhausia is described from the upper rio Negro basin, Amazonas, Brazil. The new species is distinguished from all congeners, except M. agnesae, by presenting a color pattern ...characterized by the presence of two irregularly-shaped humeral blotches, and the presence of dark longitudinal stripes on the dorsal portion of the body. The new species can be readily separated from M. agnesae by presenting longitudinal stripes straight and more conspicuous dorsally, humeral blotches contacting each other, 2-3 tricuspid maxillary teeth, 32-35 lateral-line scales, and length of maxilla 45.3-51.0% in head length.
Value-added materials produced from broiler manure can be a renewable alternative to its problematic disposal. Pyrolysis of broiler manure (litter and cake) produces char, bio-oil, and biogas. In ...this study broiler manure chars were characterized for their ability to adsorb selected metal ions. Char yields for pelletized broiler manure slowly pyrolyzed at 700 and 800 °C for 1 h ranged between 29.6% and 33.5%. Surface areas for the broiler litter and cake decreased with pyrolysis temperature with 238 and 318 m2/g and 199 and 261 m2/g for 700 and 800 °C, respectively. Broiler manure chars removed significantly more metal ions from solution (up to 0.91 mmol/g Cu2+ and 0.96 mmol/g Zn2+) when compared to chars produced from coal, wood, or coconut shells (up to 0.0 mmol/g Cu2+ and 0.10 mmol/g Zn2+). Composition of the biogas generated during fast pyrolysis between 700-900 °C, as a measurement of its energy potential, was also determined. The major components of the noncondensable gas produced during fast pyrolysis of broiler manure, included CO, CO2, low molecular weight hydrocarbon gases, and H2. Except for CO, noncondensable gases increased with pyrolysis temperature.
Broiler manure produced at large concentrated facilities poses risks to the quality of water and public health. This study utilizes broiler litter and cake as source materials for granular activated ...carbon production and optimizes conditions for their production. Pelletized manure samples were pyrolyzed at 700 °C for 1 h followed by activation in an inert atmosphere under steam at different water flow rates, for a period ranging from 15 to 75 min. Carbon physical and adsorptive properties were dependent on activation time and quantity of steam used as activant, yields varied from 18% to 28%, surface area varied from 253 to 548 m
2/g and copper ion adsorption varied from 0.13 to 1.92 mmol Cu
2+/g carbon. Best overall performing carbons were steam activated for 45 min at 3 ml/min. Comparative studies with commercial carbons revealed the broiler cake-based carbon as having the highest copper ion efficiency.
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