982 research outputs found
Global systematic map of research on bats in agricultural systems
Introduction: The conversion of natural habitats to agricultural systems is one of the main global threats to bats. Here, we aimed to develop a systematic mapping to identify publication trends and research gaps in studying bats and agricultural systems.
Methods: We reviewed 309 studies published between 1990 and 2021 that sampled bats in agricultural systems or evaluated the effect of these systems on these animals.
Results: We found that most studies were conducted in the Palearctic and Neotropical regions (55.3%) and forest biomes (66.0%). Grassland-cropland systems (50.2%) and forest plantations that do not require cutting during the extraction of their products (47.9%) were more studied than forest plantations that require cutting (19.7%). Additionally, acoustic recordings (41.1%) and mist nets (34.3%) were the primary sampling methods used, with few studies combining these methods (7.1%). Also, most studies were conducted on a local scale (77.7%). The number of landscape-scale studies was smaller (34.3%) and concentrated in the Palearctic region (39.6%). Most studies assessed how agricultural systems affect biodiversity (62.1%). However, the phylogenetic and functional dimensions and b-diversity were little explored, with 2.5% and 23.3% of the biodiversity studies, respectively. Of the proposed mitigation measures, the most cited was including natural/semi-natural/potential bat habitats in cultivated landscapes (59.5%).
Discussion: In summary, our findings highlight the need for attention to the Afrotropic and Indo-Malaysia regions; predominantly non-forested biomes; plantations that require cutting during the extraction of their products; combined use of different sampling methods, as well as other methods as telemetry; use of multiple biodiversity descriptors and others biological descriptors, such as ecological services; landscape-scale studies and the role of conservation policies in promoting their conservation and raising awareness of their importance among producers and local communities. Filling these knowledge gaps is necessary to understand the factors influencing bat survival in cultivated landscapes. This is the only way to develop management and conservation strategies in these landscapes.info:eu-repo/semantics/publishedVersio
Losses and Dry Matter Recovery of Pioneiro Grass (\u3cem\u3ePennisetum purpureum\u3c/em\u3e Schumach) and Maize Silages in Mixtures
Forages ensiled with high moisture content produce increased quantities of effluents losing highly digestible nutrients (McDonald 1981). The ensilage process usually involves gaseous and effluent losses which are strictly related to the moisture content of the plants used for conservation. The addition of materials with high dry matter content and materials which improve the fermentation pattern has been an alternative to reduce these effluent losses. The maize plant and maize grain, by their physical and fermentative characteristics, may represent alternatives to reduce the losses in the process (Anaya-Ortega et al. 2009). This work was carried out with the aim to evaluate the effect of whole plant maize and maize grain addition to silages of Pioneiro grass as way to control dry matter losses
A dimensão sociopolÃtica da matemática: em foco os processos formativos do professor indÃgena
O presente trabalho, de cunho teórico, objetiva discutir o processo de formação inicial de professores Kaingang no curso de licenciatura intercultural indÃgena em matemática e ciências da natureza. O estudo tem aporte teórico na educação matemática crÃtica. Propomos pensar a formação de modo a potencializar o acadêmico indÃgena à luz do cenário de sua cultura, com uma educação matemática para o empowerment. Para ressaltar esse potencial, tratamos da matemacia. Destacamos a necessidade de pensar os critérios utilizados na construção dos conceitos matemáticos e superar a ideologia da certeza, dada em função do pensamento hegemônico acerca da universalidade da matemática
Electrochemical and electrochromic properties of poly(4,4 dimethoxy 3'-methyl 2,2':5',2 terthiophene)
This work describes the electrochemical, spectroelectrochemical and electrochromic properties of poly(4,4 dimethoxy 3'-methyl 2,2':5',2 terthiophene) thin films. The effect of temperature on the electropolymerization was studied by cyclic voltammetry measured in situ. The temperatures used were -10, 0, 10, 20, and 40 ºC. Results indicate that the electropolymerization temperature directly affect the degree of chain organization. The optical response time for bleaching was 0.8 s and for coloring 0.3 s (for films synthesized at 40 ºC, 60 nm thick). After 1400 electrochromic cycles, the chromatic contrast at 570 nm changes from 31 to 14%. The coloration efficiency was enhanced as a function of redox cycling. This was probably caused by a decrease in the injected charge necessary for the color change, suggesting that the electroactive losses occurring during the cycles are related to sites not responsible for electrochromic contrast.Este trabalho descreve o estudo das propriedades eletroquÃmicas, espectroeletroquÃmicas e eletrocrômicas de filmes finos de poli(4,4 dimetoxi 3'-metil 2,2':5',2 tertiofeno). A voltametria cÃclica in situ foi usada para estudar o efeito da temperatura sobre a eletropolimerização. As temperaturas utilizadas na deposição eletroquÃmica foram -10, 0, 10, 20 e 40 ºC. Os resultados indicaram que a temperatura de eletropolimerização afeta diretamente o grau de ordenamento molecular do polÃmero. O tempo de resposta eletrocrômico foi de 0,8 s para clareamento e 0,3 s para escurecimento (para filmes sintetizados a 40 ºC, espessura de 60 nm). Após 1400 ciclos eletrocrômicos, o contraste óptico a 570 nm diminuiu de 31 para 14%. A eficiência eletrocrômica foi intensificada em função do número de ciclos eletrocrômicos. Este fato foi provavelmente causado pela diminuição da carga injetada, necessária para a mudança de cor, sugerindo que as perdas na eletroatividade estão associadas a sÃtios que não são responsáveis pela mudança de coloração.733738Conselho Nacional de Desenvolvimento CientÃfico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de NÃvel Superior (CAPES
Predictive Maintenance Model Based on Anomaly Detection in Induction Motors: A Machine Learning Approach Using Real-Time IoT Data
With the support of Internet of Things (IoT) devices, it is possible to
acquire data from degradation phenomena and design data-driven models to
perform anomaly detection in industrial equipment. This approach not only
identifies potential anomalies but can also serve as a first step toward
building predictive maintenance policies. In this work, we demonstrate a novel
anomaly detection system on induction motors used in pumps, compressors, fans,
and other industrial machines. This work evaluates a combination of
pre-processing techniques and machine learning (ML) models with a low
computational cost. We use a combination of pre-processing techniques such as
Fast Fourier Transform (FFT), Wavelet Transform (WT), and binning, which are
well-known approaches for extracting features from raw data. We also aim to
guarantee an optimal balance between multiple conflicting parameters, such as
anomaly detection rate, false positive rate, and inference speed of the
solution. To this end, multiobjective optimization and analysis are performed
on the evaluated models. Pareto-optimal solutions are presented to select which
models have the best results regarding classification metrics and computational
effort. Differently from most works in this field that use publicly available
datasets to validate their models, we propose an end-to-end solution combining
low-cost and readily available IoT sensors. The approach is validated by
acquiring a custom dataset from induction motors. Also, we fuse vibration,
temperature, and noise data from these sensors as the input to the proposed ML
model. Therefore, we aim to propose a methodology general enough to be applied
in different industrial contexts in the future
Study of a desulfurization process to convert dibenzothiophene to 2-hydroxybiphenyl by Rhodococcus rhodochrous NRRL (B-2149)
[Abstract] Actually, a great effort is being given to research on biodesulfurization processes, i.e., processes in which sulfur can be removed selectively from sulfur-compound moities without altering its British thermal unit. This effort relies on the fact that fossil fuels (coal and oil) contain organic sulfur compounds that are released after combustion to the environment mainly as SO2 that causes acid rain becoming a potential pollutant. In this work we investigate the biodesulfurization of a model molecule that represents the main class of a group of recalcitrant compounds found in petroleum, Dibenzothiophene (DBT), to produce 2-Hydroxybiphenyl (2-HBP), a sulfur-free compound, by Rhodococcus rhodochrous (NRRL B-2149) using the 4S pathway. Experiments in which R. rhodochrous (NRRL B- 2149) was cultived during exponential growth phase using glucose and DBT as carbon and energy and sulfur sources, respectively, showed that the microorganism follows the 4S metabolic pathway in which DBT is converted to 2-HBP and sulfite. It was also showed that R. rhodochrous (NRRL B-2149) has cell-bounding surface active agents that that facilitates the emulsification of the apolar – water immiscible DBT
Catalytic reutilization of chromium-loaded NaY oxidation of ethyl acetate
EUROPACAT IX - Catalysis for a Sustainable WorldThe
aim
of
this
study
is
the
reutilization
of
new
materials
obtained
by
biorecovery
of
chromium
from
water,
in
catalytic
oxidations
of
volatile
organic
compounds.
A
biosorption
system
consisting
of
a microorganism
supported
on
a NaY
zeolite
was
used
to
remove
hexavalent
chromium
from
contaminated
water.
After
the
biosorption
process,
the
chromium-loaded
zeolite
was
used
as
catalyst
to
be
applied
in
catalytic
oxidation
of
ethyl
acetate.
The
results
showed
that
a higher content
of
chromium
enhanced
the
activity
and
the
C0
2
selectivity
of
the
catalystinfo:eu-repo/semantics/publishedVersio
Spectroscopic and Theoretical Studies of Some 3-(4 '-Substituted phenylsulfanyl)-1-methyl-2-piperidones
The analysis of the IR carbonyl bands of some 3-(4 '-substituted phenylsulfanyl)1- methyl-2-piperidones 1-6 bearing substituents: NO2 (compound 1), Br (compound 2), Cl (compound 3), H (compound 4) Me (compound 5) and OMe (compound 6) supported by B3LYP/ 6-31+ G(d, p) and PCM calculations along with NBO analysis (for compound 4) and X-ray diffraction (for 2) indicated the existence of two stable conformations, i.e., axial (ax) and equatorial (eq), the former corresponding to the most stable and the least polar one in the gas phase calculations. the sum of the energy contributions of the orbital interactions (NBO analysis) and the electrostatic interactions correlate well with the populations and the vCO frequencies of the ax and eq conformers found in the gas phase. Unusually, in solution of the non-polar solvents n-C6H14 and CCl4, the more intense higher IR carbonyl frequency can be ascribed to the ax conformer, while the less intense lower IR doublet component to the eq one. the same.CO frequency trend also holds in polar solvents, that is nu(CO(eq)) < nu(CO(ax)). However, a reversal of the ax/eq intensity ratio occurs going from non-polar to polar solvents, with the ax conformer component that progressively decreases with respect to the eq one in CHCl3 and CH2Cl2, and is no longer detectable in the most polar solvent CH3CN. the PCM method applied to compound 4 supports these findings. in fact, it predicts the progressive increase of the eq/ax population ratio as the relative permittivity of the solvent increases. Moreover, it indicates that the computed.CO frequencies of the ax and eq conformers do not change in the non-polar solvents n-C6H14 and CCl4, while the.CO frequencies of the eq conformer become progressively lower than that of the ax one going from CHCl3 to CH2Cl2 and to CH3CN, in agreement with the experimental IR values. the analysis of the geometries of the ax and eq conformers shows that the carbonyl oxygen atom of the eq conformer is free for solvation, while the O-[CO]center dot center dot center dot H[o-Ph] hydrogen bond that takes place in the ax conformer partially hinders the approach of the solvent molecules to the carbonyl oxygen atom. Therefore, the larger solvation that occurs in the carbonyl oxygen atom of the eq conformer is responsible for the observed and calculated decrease of the corresponding frequency. the X-ray single crystal analysis of 2 indicates that this compound adopts the most polar eq geometry in the solid. in fact, in order to obtain the largest energy gain, the molecules are arranged in the crystal in a helical fashion due to dipole moment coupling along with C-H center dot center dot center dot O and C-H center dot center dot center dot pi(Ph) hydrogen bonds.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento CientÃfico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de NÃvel Superior (CAPES)MIUR (PRIN)Univ São Paulo, Inst Chem, Conformat Anal & Elect Interact Lab, BR-05513970 São Paulo, BrazilUniversidade Federal de São Paulo, UNIFESP, Inst Environm Chem & Pharmaceut Sci, BR-09972270 Diadema, SP, BrazilUniv Fed Sao Carlos, Dept Chem, BR-13565905 Sao Carlos, SP, BrazilUniv Ferrara, Dept Chem, I-44100 Ferrara, ItalyUniversidade Federal de São Paulo, UNIFESP, Inst Environm Chem & Pharmaceut Sci, BR-09972270 Diadema, SP, BrazilCAPES: 808/2009Web of Scienc
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