The dehydrogenation reaction of light alkanes in gallium-containing zeolites was studied by using density functional theory (DFT) and a nonframework gallium species in the dihydridegallium ion form. Two different mechanisms were considered: a 3-step mechanism and a 1-step concerted mechanism. The reactions occurring through the 3-step mechanism showed smaller activation barriers than the ones following the concerted mechanism. However, the energy barrier for the 3-step mechanism seems to be more influenced by the size and type (linear or branched) of the hydrocarbon chain and demands major conformational rearrangement, which could be hampered by the zeolite framework, especially for larger and/or branched hydrocarbons. On the other hand, the concerted mechanism seems to be much less dependent on the substrates geometry. Therefore, the concerted mechanism could be preferential when dealing with larger and/or branched alkanes.

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The origin of the anomeric effect has remained an open question. After Mo demonstrated that hyperconjugation is not responsible for the anomeric effect [Y. Mo, Nature Chem., 2010, 2, 666.], electrostatic interactions and Pauli repulsions have been at the center of this debate. In this work, the total energies of the most stable rotamers of the equatorial and axial anomers of fluoro, hydroxyl, cyano and amino groups in cyclohexane and 2-substituted tetrahydropyran rings are decomposed into their fundamental kinetic, electrostatic and exchange components. In this partitioning scheme, the differences in the total energies among the most stable rotamers of each anomer correlate very well with the differences in the exchange components, revealing that the anomeric effect has no electrostatic origin. Indeed, the anomeric effect is dominated by the exchange energy. This proposal for the origin of the anomeric effect brings new insights that, once incorporated, may improve qualitative chemical models. Implications of this new proposal for the origin of the anomeric effect on geometric parameters and solvation are also discussed.

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Glyphosate (N-(phosphonomethyl)glycine) (Gph) is a herbicide that is broadly used in several countries. Its application to eliminate weeds may have the undesired effect of diminishing the metallic cations found in the soil (e.g., Ni(2+) and Zn(2+)), due to a complexation reaction that depends on the soil's pH. To better understand the molecular structures of glyphosate that are involved in such a complexation reaction, we have studied all possible glyphosate conformations in aqueous solution that may be involved in deprotonation reactions in the pH range from 2 to 11 using the polarizable continuum method (PCM). We have also compared direct (or absolute) methods to calculate pKa values, the cluster-continuum model and the proton-exchange scheme, using different thermodynamic cycles. The best result was achieved when using a proton-exchange scheme, which was able to properly reproduce three glyphosate experimental pKa values predicted for the glyphosate structures and conformations previously determined.

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The issue domestic violence against women has become more visible in our society, regardless of social class, age, ethnicity or educational level. There are numerous cases of violence against women in forensic services, most of which consisting of lesions produced by forceful action. The objective of this article is to investigate the occurrence of orofacial injuries in female victims of domestic violence, the observation of the most commonly affected parts of the body and the offender's profile. This is an integrative literature obtained through databases SCIELO, LILACS, PubMed, Medline, and Bireme, covering national and international studies published along the years from 1993 to 2013. The keywords used were: violence against women, domestic violence, orofacial injuries and maxillo-facial trauma in the period between 2011 and 2013. It has been observed that the progressive increase in violence against women has become the target of several investigations, and the biggest offender in most cases is the partner/spouse or ex-partner, and the most affected area is the face, because besides the painful symptoms felt, there is aesthetic involvement , which will also affect the victim psychologically. The profile shows women victims, mostly women from the periphery of the city, presenting injuries or blunt cut in regions of the lips, eyelids and orbits without compromising function or permanent 2