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Removal of Cr(VI) from the aqueous phase using numerous activated carbons (AC) has been broadly studied in the last decades. Nevertheless, the diversity of activation methods, AC properties, and adsorption conditions precludes the standardization of specific characteristics required to achieve better adsorption results. This work reviewed the pertinent literature on Cr(VI) adsorption onto AC published over the past four decades. Pearson's correlation matrix and principal component analysis (PCA) assisted in identifying the parameters and AC characteristics that have the greatest influence on the maximum adsorption capacity (qm). Two hundred thirty-six adsorption assays were found reporting data on 110 ACs and different parameters. Of these, 39.8% of the studies contemplated the variables qm, pH, temperature (T), surface area (SBET), micropore volume (Vmicro), and mesopore volume (Vmeso), and only 19.5% reported the point of zero charge (pHPZC). Statistical analysis disclosed that SBET and Vmicro have a strong positive correlation with qm, while Vmeso, T, and pH show little or no correlation. The difference between pH and pHPZC (PZCdiff) indicated a significant anticorrelation with qm, thus evidencing that lower PZCdiff values enhance adsorption. The findings are useful for all researchers that work with Cr(VI) adsorption on AC since they provide a start point concerning the required adsorbent characteristics and process conditions to be employed. [ABSTRACT FROM AUTHOR]

In recent years, the search for alternatives to the use of synthetic chemical additives in food has led to an increase in research focused on essential oils (EOs). Among the EOs with food applications already described in the literature, the essential oil extracted from basil (Ocimum basilicum L.) stands out, which presents several biological activities. This review was conducted to discuss the basil essential oil (BEO), presenting information on the different extraction methods and their influence on the compounds, in addition to presenting biological and toxicological aspects. The extraction method and the qualitative and quantitative variation of the compounds are highly dependent on factors such as type of cultivar; date, place, and conditions of cultivation; and seasonal variation and harvest. In addition, the main biological activities of basil essential oil are dependent of the chemical constituents, such as estragole, linalool, eugenol, eucalyptol, and bergamotene, and can act in isolation or in synergism. [ABSTRACT FROM AUTHOR]

Nanotechnology has been widely used, with nanomaterials being applied in several technologies. However, little is known about the real toxicological risk that can be caused by nanomaterials. These materials can be divided according to their dimensionalities. The current classification schemes for nanostructured materials are based on these dimensionalities, generally as zero (0D), one (1D), two (2D), and three dimensions (3D). Toxicological studies to present broad and consistent information on nanomaterials toxicity mechanisms, in vitro and in vivo studies in several experimental models are necessary. Thus, this short review presents the toxicological potential of carbon nanomaterials, divided by their dimensionality, in the main in vitro and in vivo experimental models, especially alternative models. As a result, it was possible to observe that the toxicity of carbon nanomaterials does not vary according to the dimensionality of 0D, 1D, and 2D materials. For these materials, it is not possible to infer a direct relationship between dimensionality and toxicity. However, recent studies have shown that three-dimensional graphene species tend to have less toxicity than materials with a smaller number of dimensions. Finally, it was possible to note the importance of using several experimental models, especially alternative models, in order to increase the understanding of toxicity mechanisms of carbon nanomaterials. [ABSTRACT FROM AUTHOR]

Urine has been a biological matrix of choice for drug screening, but recent advances in technology and the introduction of commercial oral fluid assays have effectively established oral fluid as a viable alternative matrix. This systematic review aimed to evaluate the sensitivity of oral fluid in detecting some illicit drugs compared to urine, and to compare the initial and final detection times of these drugs in both fluids. The electronic search in MEDLINE, Cochrane Library, Scopus, and Web of Science was carried out covering studies published from January 2003 and June 2019, in order to find all valid studies that detected drugs in oral fluid and urine in the same patient. Studies about illicit drugs, such as tetrahydrocannabinol, cocaine, amphetamines and illicit opioids, with fluids collection at the same day, controlled drug administration during the study, reported administration interval and time of collection were favored. Out of 2598 studies identified by electronic search, 7 studies were selected for qualitative analysis. Five were clinical trials and 2 were crossover trials. In total, 74 patients aged 20–52 years underwent a diagnostic examination (4 studies with tetrahydrocannabinol, 1 with methamphetamine, and 2 with cocaine) after drug administration. Illicit drug detection in oral fluid is similar to urine but oral fluid has a strong potential for the immediate detection of recent marijuana use compared to urine. In relation to cocaine and methamphetamine, the largest drugs detection window is obtained through urine analysis. Oral fluids cannot replace urine for most of the purposes of drug testing. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the in vitro bond strength of universal adhesive systems to indirect substrates. Material and Methods: Two reviewers performed a literature search up to March 2018 in seven databases: PubMed, Web of Science, SciELO, Scopus, LILACS, IBECS, and BBO. The review included studies that compared the bond strength of universal adhesives and well‐established material‐specific primers to indirect substrates: lithium disilicate ceramic, yttrium‐stabilized zirconium dioxide ceramic, leucite‐reinforced ceramic, feldspathic porcelain, polymer infiltrated ceramic material, resin composite or metal alloys. Analyses were carried out using RevMan 5.3.5. A global comparison was performed with the standardized mean difference using a random‐effects models at a significance level of p < 0.05. Results: A total of 45 studies were included in the qualitative analysis, and the meta‐analysis was performed with 42 studies. Bond strength to glass‐based ceramics and alloys was improved with the use of a specific‐primer as separate step before the bonding procedures (lithium disilicate, p < 0.001; alloys, p < 0.001). The bond strength to zirconium substrates was improved with the use of universal adhesives (p < 0.001). For bond strength to composite resin as indirect substrate, universal adhesives performed in a manner similar to that of the material‐specific primer (p = 0.11). Conclusions: The clinical procedure of luting zirconia and resin composite restorations could be simplified by using single‐bottle universal adhesives. However, the ability of universal adhesives to achieve an adequate and durable bond to glass‐based ceramics and alloys appears to be limited. [ABSTRACT FROM AUTHOR]

The article reviews the book "'Forschung tut Not' - Technik und Innovation in der Weltwirtschaftskrise 1929-1933."

Reviews the book "A Enigração Portuguesa," by Joel Serrao.