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Species distribution patterns in the Brazilian Marine Province (BMP) are extensively debated, nevertheless no study used a multi-taxa approach to investigate possible biotic distinctions and the role of environmental factors in determining biogeographical patterns in this province. Here, we compiled the largest distributional multi-taxa dataset in the southern Atlantic (2412 reef species) to address the following: (1) similarities among areas accounting for species composition and environmental characteristics; (2) the absolute species richness of nine taxonomic groups among geographical bins; and (3) how species biogeographical patterns are explained by the environmental similarities. We hypothesized sub-provinces' limits will be strongly correlated to environmental delimitations, being sea surface temperature a central component influencing biotic subdivision on the BMP. We found eight different geographical bins considering the environmental factors, while five considering species distributions. We also observed a latitudinal gradient of species richness for most taxa, some presenting a 'mid-domain' shape pattern. Beta diversity among sub-provinces was low, and the nestedness component more important, indicating high connectivity along the BMP. Using a db-RDA, we demonstrated that environmental variables explained 64% of species clustering patterns, with sea surface temperature, water turbidity and current velocity explaining the biotic clustering of the Brazilian northeastern coast. Sub-provinces North and Abrolhos Bank were the most distinct areas regarding environmental and biotic data. Our study highlights the importance of using a multi-taxa approach to understand the relationship between biogeographical patterns, as well as its response to environmental and historical factors., Author(s): Isadora Cord [sup.1] , Lucas T. Nunes [sup.1] , Cristiane X. Barroso [sup.2] , Andrea S. Freire [sup.3] , Otto B. F. Gadig [sup.4] , Paula B. Gomes [sup.5] [...]

The standard molar energies of combustion of 1-methylpiperidine (1), 3-methylpiperidine (2), 4-methylpiperidine (3), 2,6-dimethylpiperidine (4) and 3,5-dimethylpiperidine (5) compounds in liquid state were measured by static bomb combustion calorimetry. The numerical values of the enthalpies of formation in the liquid and in the gaseous states are respectively, -(95.6) and -(59.1) kJ.[mol.sup.-1] for (1); -(123.6) and -(79.2) kJ.[mol.sup.-1] for (2); -(123.5) and -(82.9) for (3); -(153.6) and -(111.2) for (4); and -(155) and -(105.9) for ().

The derivation of the standard molar enthalpies of formation in the gaseous state of a new phenazine derivative, 2-hydroxyphenazine-di-N-oxide, is reported. The mean molar dissociation enthalpy of the (N-O) bonds is derived for the 2-hydroxyphenazine-di-N-oxide species.

A "hands-on" robotic system for total knee replacement (TKR) surgery is presented. A computer tomography-based preoperative planning software is used to accurately plan the procedure. Intraoperatively, the surgeon guides a small special-purpose robot, called Acrobot, which is mounted on a gross positioning device. The Acrobot uses active constraint control, which constrains the motion to a predefined region, and thus allows the surgeon to safely cut the knee bones to fit a TKR prosthesis with high precision. A noninvasive anatomical registration method is described. The system has been successfully used in seven clinical trials with encouraging results. Index Terms--Acrobot, active constraints, hands-on robotics, orthopaedic robotic surgery, total knee replacement (TKR).

The studies related to the stereoselectivity of imidazolidin-4-one formation from primaquine [alpha]-aminoamides and various substituted benzaldehydes revealed that a crucial role is played by intramolecular hydrogen-bonds involving the C=O oxygen of the o-substituent.

Several thermochemical studies of the 3-methyl-quinoxaline-2-carboxamide-1,4-dioxide derivatives are conducted to determine the enthalpies of formation and dissociation of the N-O bond. The size of the substituent is shown to have no effect on the N-O bond dissociation enthalpies.

A study investigates the ability of a novel lysine-derived surfactant with a gemini-like architecture, designated 12-Lys-12, to form in aqueous solution, catanionic vesicles with an oppositely charged synthetic surfactant. Results show that in a dodecyltrimethylammonium bromide (DTAB)-rich side micelle-to-vesicle transition takes place via a discontinuous process, involving first limited micellar growth and then phase separation.

Differential scanning calorimetry (DSC), circular dichroism (CD), and quassi-elastic light scattering (QELS) were used to study the interaction of two hybrid peptides of cecropin A and melittin [CA(1-8)M(1-7) and CA(1-7)M(2-9)] with liposomes. The results indicate that, for both peptides, the interaction depended on membrane composition, with different behavior for zwitterionic and anionic membranes.