Stimulatory effects of defective and effective 3-indoleacetic acid-producing bacterial strains on rice in an advanced stage of its vegetative cycle.

The production of 3-indoleacetic acid (IAA) by plant growth-promoting bacteria (PGPR) stimulates root development and plant growth. In addition, morphological changes such as an increased root ramification and root hair production improves nutrient absorption and biomass accumulation. The objective of this work was to evaluate the effect of IAA-producing strains on rice in an advanced stage of its vegetative cycle. Rice was inoculated with Gluconacetobacter diazotrophicus PAL 5 and its lao- mutant, deficient in auxin production, Azospirillum baldaniorum Sp 245, and Escherichia coli DH10b. Both the mutant and wild-type G. diazotrophicus stimulated root elongation, area, volume, and diameter. However, the lao- mutant strain was the only one capable of increasing the number of roots. In turn, inoculation with A. baldaniorum had no significant effect on plant development. The inoculation with E. coli led to changes in root volume, area, and diameter, and a response that may be related to the stress caused by its presence. We conclude that the inoculation with G. diazotrophicus stimulates the root system's growth independently of their IAA production ability, suggesting that a metabolite other than IAA is responsible for this effect at advanced stages of the rice's vegetative cycle.

Distinguishing cotton seed genotypes by means of vibrational spectroscopic methods (NIR and Raman) and chemometrics.

The use of vibrational spectroscopy, such as near infrared (NIR) and Raman, combined with multivariate analysis methods to analyze agricultural products are promising for investigating genetically modified organisms (GMO). In Brazil, cotton is grown under humid tropical conditions and is highly affected by pests and diseases, requiring the use of large amounts of phytosanitary chemicals. To avoid the use of those pesticides, genetic improvement can be carried out to produce species tolerant to herbicides, resistant to fungi and insects, or even to provide greater productivity and better quality. Even with these advantages, it is necessary to manage and limit the contact of transgenic species with native ones, avoiding possible contamination or even extinction of conventional species. The identification of the presence of GMOs is based on complex DNA-based analysis, which is usually laborious, expensive, time-consuming, destructive, and generally unavailable. In the present study, a new methodology to identify GMOs using partial least squares discriminant analysis (PLS-DA) on NIR and Raman data is proposed to distinguish conventional and transgenic cotton seed genotypes, providing classification errors for prediction set of 2.23% for NIR and 0.0% for Raman.

Humic Substances in Combination With Plant Growth-Promoting Bacteria as an Alternative for Sustainable Agriculture.

Plant growth-promoting bacteria (PGPB) and humic substances (HSs) are promising options for reducing the use of pesticides and mineral fertilizers. Although many studies have shown the effects of PGPB and HSs separately, little information is available on plant responses to the combined application of these biostimulants despite the great potential for the simultaneous action of these biological inputs. Thus, the objective of this review is to present an overview of scientific studies that addressed the application of PGPB and HSs to different crops. First, we discuss the effect of these biostimulants on biological nitrogen fixation, the various effects of the inoculation of beneficial bacteria combined with the application of HSs on promoting the growth of nonleguminous plants and how this combination can increase bacterial colonization of plant hosts. We also address the effect of PGPB and HSs on plant responses to abiotic stresses, in addition to discussing the role of HSs in protecting plants against pathogens. There is a lack of studies that address the role of PGPB + HSs in biocontrol. Understanding the factors involved in the promotion of plant growth through the application of PGPB and HSs can assist in the development of efficient biostimulants for agricultural management. This approach has the potential to accelerate the transition from conventional cultivation to sustainable agrosystems.

Chemometric strategies for near infrared hyperspectral imaging analysis: classification of cotton seed genotypes.

Hyperspectral images have been increasingly employed in the agricultural sector for seed classification for different purposes. In the present paper we propose a new methodology based on HSI in the near infrared range (HSI-NIR) to distinguish conventional from transgenic cotton seeds. Three different chemometric approaches, one pixel-based and two object-based, using partial least squares discriminant analysis (PLS-DA) were built and their performances were compared considering the pros and cons of each approach. Specificity and sensitivity values ranged from 0.78-0.92 and 0.62-0.93, respectively, for the different approaches.

Quality by design applied to olanzapine and quetiapine LC-MS/MS bioanalysis.

One major challenge in quantifying drugs in biological matrices is to manage interfering compounds. A technique such liquid chromatography coupled to mass spectrometry in tandem (LC-MS/MS) is especially suitable for this application due to its high sensitivity and selectivity in detecting low concentrations of analytes in a complex system. Due to the complexity of LC-MS/MS systems, a number of experimental parameters must be optimized to provide an adequate separation and detection of the analyte. In the present work, a design of experiments approach was developed to optimize an LC-MS/MS-based bioanalytical method to extract olanzapine (OLZ) and quetiapine (QTP) from human plasma. Three steps for the optimization process were conducted: central composite face-centered design to optimize chromatographic parameters (Step 1), ionization in mass spectrometry (Step 2) and a full 32 factorial design to optimize analyte extraction conditions (Step 3). After the optimization process, resolutions and QTP and OLZ retention time (2.3 and 4, respectively) were optimum with pH of 4.7 and 85.5% of acetonitrile for the chromatographic step. Mass spectrometry optimization step provided an increase of (±50%) in the average peak area with high signal-to-noise relationship for the analytes studied. The proposed extraction method was 70% more efficient than the initial method for all drugs analyzed.

Biological diversity of carbon assimilation among isolates of the yeast Dekkera bruxellensis from wine and fuel-ethanol industrial processes.

Dekkera bruxellensis is considered a spoilage yeast in winemaking, brewing and fuel-ethanol production. However, there is growing evidence in the literature of its biotechnological potential. In this work, we surveyed 29 D. bruxellensis isolates from three countries and two different industrial origins (winemaking and fuel-ethanol production) for the metabolization of industrially relevant sugars. The isolates were characterized by the determination of their maximum specific growth rates, and by testing their ability to grow in the presence of 2-deoxy-d-glucose and antimycin A. Great diversity was observed among the isolates, with fuel-ethanol isolates showing overall higher specific growth rates than wine isolates. Preferences for galactose (three wine isolates) and for cellobiose or lactose (some fuel-ethanol isolates) were observed. Fuel-ethanol isolates were less sensitive than wine isolates to glucose catabolite repression (GCR) induction by 2-deoxy-d-glucose. In strictly anaerobic conditions, isolates selected for having high aerobic growth rates were able to ferment glucose, sucrose and cellobiose at fairly high rates without supplementation of casamino acids or yeast extract in the culture medium. The phenotypic diversity found among wine and fuel-ethanol isolates suggests adaptation to these environments. A possible application of some of the GCR-insensitive, fast-growing isolates in industrial processes requiring co-assimilation of different sugars is considered.

Cenários de gestão de saúde e segurança em frigoríficos gaúchos: contribuições e lacunas da medicina do trabalho / Scenarios of health management and security in gaucho refrigerators: contributions and gaps in occupational medicine

Demonstrar as situações encontradas de gestão e segurança no trabalho em frigoríficos, especialmente através da medicina do trabalho. (AU)

Subnotificação de distúrbios osteomusculares em frigoríficos do Rio Grande do Sul

Objetiva evidenciar a subnotificação dos distúrbios osteomusculares relacionados ao trabalho nos frigoríficos que receberam ação da Força-Tarefa do Ministério Público do Trabalho entre os anos de 2014 e 2016. (AU)

Procrustes rotation as a diagnostic tool for projection pursuit analysis.

Projection pursuit (PP) is an effective exploratory data analysis tool because it optimizes the projection of high dimensional data using distributional characteristics rather than variance or distance metrics. The recent development of fast and simple PP algorithms based on minimization of kurtosis for clustering data has made this powerful tool more accessible, but under conditions where the sample-to-variable ratio is small, PP fails due to opportunistic overfitting of random correlations to limiting distributional targets. Therefore, some kind of variable compression or data regularization is required in these cases. However, this introduces an additional parameter whose optimization is manually time consuming and subject to bias. The present work describes the use of Procrustes analysis as diagnostic tool that can be used to evaluate the results of PP analysis in an efficient manner. Through Procrustes rotation, the similarity of different PP projections can be examined in an automated fashion with "Procrustes maps" to establish regions of stable projections as a function of the parameter to be optimized. The application of this diagnostic is demonstrated using principal components analysis to compress FTIR spectra from ink samples of ten different brands of pen, and also in conjunction with regularized PP for soybean disease classification.