Detecting dynamical changes in vital signs using switching Kalman filter

Vital signs contain valuable information about patients' health status during their stay in general wards, when the deterioration process begins. The use of methods to predict and detect regime changes such as switching models can help to understand how vital sign dynamics are altered in disease conditions. However, time series of vital signs are remarkably non-stationary in these scenarios. The objective of this study is to quantify the potential bias of switching models in the presence of non-stationarities, when the inputs are spectral, symbolic and entropy indices. To distinguish stationary from non-stationary periods, a test was used to verify the stability of the mean and variance over short periods. Then, we compared the results from a switching Kalman filter (SKF) model trained using indices obtained over stationary periods with a model trained solely over non-stationary periods. It was observed that indices measured over stationary and non-stationary periods were significantly different. The results of switching models were highly dependent on the indices that were used as inputs. The multi-scale entropy (MSE) approach presented the highest correlation values between non-stationary and stationary switches, an average correlation coefficient of 38%

Early warnings of heart rate deterioration

Hospitals can experience difficulty in detecting and responding to early signs of patient deterioration leading to late intensive care referrals, excess mortality and morbidity, and increased hospital costs. Our study aims to explore potential indicators of physiological deterioration by the analysis of vital-signs. The dataset used comprises heart rate (HR) measurements from MIMIC II waveform database, taken from six patients admitted to the Intensive Care Unit (ICU) and diagnosed with severe sepsis. Different indicators were considered: 1) generic early warning indicators used in ecosystems analysis (autocorrelation at-1-lag (ACF1), standard deviation (SD), skewness, kurtosis and heteroskedasticity) and 2) entropy analysis (kernel entropy and multi scale entropy). Our preliminary findings suggest that when a critical transition is approaching, the equilibrium state changes what is visible in the ACF1 and SD values, but also by the analysis of the entropy. Entropy allows to characterize the complexity of the time series during the hospital stay and can be used as an indicator of regime shifts in a patient's condition. One of the main problems is its dependency of the scale used. Our results demonstrate that different entropy scales should be used depending of the level of entropy verified

Economic analysis of silvipastoral systems eligible for the Carbon Neutral Brazilian Beef protocol.

Editores: Alexandre Bernd, Luiz Gustavo Pereira Ribeiro, Adibe Luis Abdalla

Emissions and carbon sequestration in silvipastoral cattle systems.

Editores: Alexandre Bernd, Luiz Gustavo Pereira Ribeiro, Adibe Luis Abdalla

Qualidade de frutos de abacaxi cultivado em diferentes épocas de plantio em sequeiro e irrigado.

No Acre existe um período de seca (junho, julho e agosto) curto onde os regimes pluviométricos não ultrapassam 50 mm ao mês, chegando a índices ao redor de 33 mm no mês de junho. Esse déficit hídrico pode comprometer seriamente o desenvolvimento da cultura do abacaxi que necessita de pelo menos 60 mm de chuva bem distribuída ao longo do mês. O objetivo do trabalho foi avaliar a influencia de diferentes épocas de plantio sobre a qualidade de frutos de abacaxizeiro. O experimento já foi implantado e conduzido no Estado do Acre, em área de produtor rural de abacaxi. O experimento foi implantado na estação seca de 2012 com os tratamentos distribuídos em esquema de parcelas subdivididas. As parcelas foram constituídas de dois tratamentos primários correspondentes a não utilização da irrigação e à utilização da prática de irrigação. As subparcelas foram constituídas das épocas de plantio correspondentes aos meses de junho, julho, agosto e setembro que é a estação seca no Acre conforme prescrito no Zoneamento Ecológico-Econômico do estado (ZEE, 2006). Os tratamentos foram distribuídos em delineamento em blocos casualizados completos com 03 repetições. Foram avaliadas as seguintes características: Massa do fruto com e sem coroa; comprimento e diâmetro do fruto; firmeza da polpa; massa da polpa; pH; teor de sólidos solúveis (SS); acidez titulável (AT) e ratio. Nas condições em que o experimento foi conduzido, conclui-se que a qualidade dos frutos de abacaxizeiro não é influenciada pela época de plantio

Emissão e sequestro de carbono em sistemas silvipastoris na fase de recria .

Sistemas silvipastoris (SSP) são alternativas para melhorar a eficiência de uso da terra, com destaque para a mitigação dos gases de efeito estufa. Objetivouse avaliar emissões e sequestro de carbono em SSP em comparação com pastagem em monocultivo (PM), com capim-piatã. Os sistemas foram estabelecidos em dezembro de 2015, em Ribas do Rio Pardo-MS

Cattle production in silvopastoral systems compared to monoculture pasture in the Brazilian Cerrado.

Adoption of silvopastoral systems (SS) in Brazil has been stimulated in the last decade. This work aimed to evaluate beef production under SS with eucalyptus using densities of 178 and 441 trees per ha and to compare it to a traditional monoculture Piatã grass pasture (PM) in the Brazilian Cerrado. Shading caused by the two tree densities, in the third year of the systems implementation did not cause changes neither on forage mass nor on its nutritive value. As consequence, results show that both SS did not differ from the PM for beef cattle production in the period studied, allowing better thermal comfort for grazing cattle, besides wood production and greenhouse gases mitigation

Carbon Neutral Brazilian Beef: testing its guidelines through a case study.

The Carbon Neutral Brazilian Beef (CNBB) is a new concept for sustainable beef production in the tropics, developed by Embrapa and first reported by Alves et al. (2015). The CNBB concept is based in silvopastoral or agrosilvopastoral systems and requires greenhouse gases emissions to be neutralized, at first, by timber production. Aim of this work is to report the first case study of CNBB application for finishing steers and to present animal performance, beef quality, pasture characteristics, microclimate parameters and carbon balance estimates

Bioinspired cyclic dipeptide functionalized nanofibers for thermal sensing and energy harvesting

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/ma16062477/s1, Figure S1: Optical microscopy; Figure S2: Output voltage as a function of time from Cyclo (L-Trp-L-Trp)@PLLA electrospun nanofibers; Figure S3: Piezoelectric current versus applied force for Cyclo (L-Trp-L-Trp)@PLLA and PLLA neat fibers, with the respective linear fits; Figure S4: Output voltage for low frequencies up to 10 Hz and output voltage as a function of time, from Cyclo (L-Trp-L-Trp)@PCL electrospun nanofibers.Nanostructured dipeptide self-assemblies exhibiting quantum confinement are of great interest due to their potential applications in the field of materials science as optoelectronic materials for energy harvesting devices. Cyclic dipeptides are an emerging outstanding group of ring-shaped dipeptides, which, because of multiple interactions, self-assemble in supramolecular structures with different morphologies showing quantum confinement and photoluminescence. Chiral cyclic dipeptides may also display piezoelectricity and pyroelectricity properties with potential applications in new sources of nano energy. Among those, aromatic cyclo-dipeptides containing the amino acid tryptophan are wide-band gap semiconductors displaying the high mechanical rigidity, photoluminescence and piezoelectric properties to be used in power generation. In this work, we report the fabrication of hybrid systems based on chiral cyclo-dipeptide L-Tryptophan-L-Tryptophan incorporated into biopolymer electrospun fibers. The micro/nanofibers contain self-assembled nano-spheres embedded into the polymer matrix, are wide-band gap semiconductors with 4.0 eV band gap energy, and display blue photoluminescence as well as relevant piezoelectric and pyroelectric properties with coefficients as high as 57 CN−1 and  35×10−6 Cm−2K−1, respectively. Therefore, the fabricated hybrid mats are promising systems for future thermal sensing and energy harvesting applications.This research was funded by Fundação para a Ciência e Tecnologia through FEDER (European Fund for Regional Development)-COMPETE-QREN-EU (ref. UID/FIS/04650/2013 and UID/FIS/04650/2019) and E-Field“Electric-Field Engineered Lattice Distortions (E-FiELD) for optoelectronic devices, ref. PTDC/NAN-MAT/0098/2020