Construction services and the Uruguay Round: major issues for Latin America

Includes bibliography

Fourier series for quaternions and the square of the error theorem

In this paper we introduce a type of Hypercomplex Fourier Series based on Quaternions, and discuss on a Hypercomplex version of the Square of the Error Theorem. Since their discovery by Hamilton (Sinegre [1]), quaternions have provided beautifully insights either on the structure of different areas of Mathematics or in the connections of Mathematics with other fields. For instance: I) Pauli spin matrices used in Physics can be easily explained through quaternions analysis (Lan [2]); II) Fundamental theorem of Algebra (Eilenberg [3]), which asserts that the polynomial analysis in quaternions maps into itself the four dimensional sphere of all real quaternions, with the point infinity added, and the degree of this map is n. Motivated on earlier works by two of us on Power Series (Pendeza et al. [4]), and in a recent paper on Liouville’s Theorem (Borges and Mar˜o [5]), we obtain an Hypercomplex version of the Fourier Series, which hopefully can be used for the treatment of hypergeometric partial differential equations such as the dumped harmonic oscillation.

Square of the Error Octonionic Theorem and Hypercomplex Fourier Series

The focus of this paper is to address some classical results for a class of hypercomplex numbers. More specifically we present an extension of the Square of the Error Theorem and a Bessel inequality for octonions.

Comparative study of histopathology and immunohistochemistry of indefinite round cell cutaneous tumors and characterization of canine lymphoma

With the purpose of shedding light on some doubts in veterinary oncology, the present article intends to compare the results of histopathological and immunohistochemical examinations of unspecific round cell neoplasia, to realize immunophenotyping of canine lymphoma cases, to establish the T or B origin of neoplastic cells, and to determine the degree of proliferation and apoptosis of lymphomas by immunohistochemistry. Of 11 animals presenting immunohistochemical diagnosis of lymphoma, five had been diagnosed as Lymphoma by HE staining of histopathological slides and six had been classified as unspecific round cell neoplasia. All cases submitted to immunohistochemical examination were T-cell lymphomas. There was a positive correlation between cell proliferation and apoptosis. The comparison among histopathological and immunohistochemical results obtained in the cases examined in the present study suggested that immunohistochemistry is essential for the differentiation of round cell neoplasia.

Experimental study on vortex-induced motions of a semi-submersible platform with four square columns, Part I: Effects of current incidence angle and hull appendages

An experimental study on Vortex-Induced Motion (VIM) of the semi-submersible platform concept with four square columns is presented. Model tests were carried out to check the influence of different headings and hull appendages (riser supports located at the pontoons; fairleads and the mooring stretches located vertically at the external column faces; and hard pipes located vertically at the internal column faces). The results comprise in-line, transverse and yaw motions, as well as combined motions in the XY plane, drag and lift forces and spectral analysis. The main results showed that VIM in the transverse direction occurred in a range of reduced velocity 4.0 up to 14.0 with amplitude peaks around reduced velocities around 7.0 and 8.0. The largest transverse amplitudes obtained were around 40% of the column width for 30 degrees and 45 degrees incidences. Another important result observed was a considerable yaw motion oscillation, in which a synchronization region could be identified as a resonance phenomenon. The largest yaw motions were verified for the 0 degrees incidence and the maxima amplitudes around 4.5 degrees. The hull appendages located at columns had the greatest influence on the VIM response of the semi-submersible. (C) 2012 Elsevier Ltd. All rights reserved.

Nuclear moments and differences in mean square charge radii of short-lived neon isotopes by collinear laser spectroscopy

Kernmomente und Kernladungsradien von kurzlebigen NeonIsotopen in der Kette 17-26,28Ne wurden mittels kollinearerLaserspektroskopie am online Massenseparator ISOLDE am CERN(Genf) vermessen. Bei kollinearer Laserspektroskopieverlangt die Bestimmung der Kernladungsradien leichterIsotope aus der Isotopeverschiebung nach einer sehr präzisenKenntnis der Ionenstrahlenergie. Zu diesem Zweck wurde eineneue, auf kollinearer Laserspektroskopie basierende Methodezur Strahlenergiemessung entwickelt und erfolgreich in denExperimenten zu Neon eingesetzt. Die experimentellenErgebnisse werden mit theoretischen Rechnungen im Rahmen desSchalenmodells und von kollektiven Kernmodellen verglichen.

Toward cell therapy using placenta-derived cells: disease mechanisms, cell biology, preclinical studies, and regulatory aspects at the round table

Among the many cell types that may prove useful to regenerative medicine, mounting evidence suggests that human term placenta-derived cells will join the list of significant contributors. In making new cell therapy-based strategies a clinical reality, it is fundamental that no a priori claims are made regarding which cell source is preferable for a particular therapeutic application. Rather, ongoing comparisons of the potentiality and characteristics of cells from different sources should be made to promote constant improvement in cell therapies, and such comparisons will likely show that individually tailored cells can address disease-specific clinical needs. The principle underlying such an approach is resistance to the notion that comprehensive characterization of any cell type has been achieved, neither in terms of phenotype nor risks-to-benefits ratio. Tailoring cell therapy approaches to specific conditions also requires an understanding of basic disease mechanisms and close collaboration between translational researchers and clinicians, to identify current needs and shortcomings in existing treatments. To this end, the international workshop entitled "Placenta-derived stem cells for treatment of inflammatory diseases: moving toward clinical application" was held in Brescia, Italy, in March 2009, and aimed to harness an understanding of basic inflammatory mechanisms inherent in human diseases with updated findings regarding biological and therapeutic properties of human placenta-derived cells, with particular emphasis on their potential for treating inflammatory diseases. Finally, steps required to allow their future clinical application according to regulatory aspects including good manufacturing practice (GMP) were also considered. In September 2009, the International Placenta Stem Cell Society (IPLASS) was founded to help strengthen the research network in this field.

Integrating the Use of Spring- and Fall-Calving Beef Cows in a Year-round Grazing System (A Progress Report)

Animal production, hay production and feeding, and the yields and composition of forage from summer and winter grass-legume pastures and winter corn crop residue fields from a year-round grazing system were compared with those of a conventional system. The year-round grazing system utilized 1.67 acres of smooth bromegrass-orchardgrass-birdsfoot trefoil pasture per cow in the summer, and 1.25 acres of stockpiled tall fescue-red clover pasture per cow, 1.25 acres of stockpiled smooth bromegrass-red clover pasture per cow, and 1.25 acres of corn crop residues per cow during winter for spring- and fall-calving cows and stockers. First-cutting hay was harvested from the tall fescue-red clover and smooth bromegrass-red clover pastures to meet supplemental needs of cows and calves during winter. In the conventional system (called the minimal land system), spring-calving cows grazed smooth bromegrass-orchardgrass-birdsfoot trefoil pastures at 3.33 acres/cow during summer with first cutting hay removed from one-half of these acres. This hay was fed to these cows in a drylot during winter. All summer grazing was done by rotational stocking for both systems, and winter grazing of the corn crop residues and stockpiled forages for pregnant spring-calving cows and lactating fall-calving cows in the year-round system was managed by strip-stocking. Hay was fed to springcalving cows in both systems to maintain a mean body condition score of 5 on a 9-point scale, but was fed to fall-calving cows to maintain a mean body condition score of greater than 3. Over winter, fall-calving cows lost more body weight and condition than spring calving cows, but there were no differences in body weight or condition score change between spring-calving cows in either system. Fall- and spring-calving cows in the yearround grazing system required 934 and 1,395 lb. hay dry matter/cow for maintenance during the winter whereas spring-calving cows in drylot required 4,776 lb. hay dry matter/cow. Rebreeding rates were not affected by management system. Average daily gains of spring-born calves did not differ between systems, but were greater than fall calves. Because of differences in land areas for the two systems, weight production of calves per acre of cows in the minimal land system was greater than those of the year-round grazing system, but when the additional weight gains of the stocker cattle were considered, production of total growing animals did not differ between the two systems.

Evaluation of Year-round Forage Management Systems for Spring- and Fall-Calving Beef Cows (A Progress Report)

A year-round grazing system for spring- and fall-calving cows was developed to compare animal production and performance, hay production and feeding, winter forage composition changes, and summer pasture yield and nutrient composition to that from a conventional, or minimal land system. Systems compared forage from smooth bromegrass-orchardgrass-birdsfoot trefoil pastures for both systems in the summer and corn crop residues and stockpiled grass-legume pastures for the year-round system to drylot hay feeding during winter for the minimal land system. The year-round grazing system utilized 1.67 acres of smooth bromegrassorchardgrass- birdsfoot trefoil (SB-O-T) pasture per cow in the summer, compared with 3.33 acres of (SB-O-T) pasture per cow in the control (minimal land) system. In addition to SB-O-T pastures, the year-round grazing system utilized 2.5 acres of tall fescue-red clover (TFRC) and 2.5 acres of smooth bromegrass-red clover (SBRC) per cow for grazing in both mid-summer and winter for fall- and spring-calving cows, respectively. First-cutting hay was harvested from the TF-RC and SB-RC pastures, and regrowth was grazed for approximately 45 days in the summer. These pastures were then fertilized with 40 lbs N/acre and stockpiled for winter grazing. Also utilized during the winter for spring-calving cows in the year-round grazing system were corn crop residue (CCR) pastures at an allowance of 2.5 acres per cow. In the minimal land system, hay was harvested from three-fourths of the area in SB-O-T pastures and stored for feeding in a drylot through the winter. Summer grazing was managed with rotational stocking for both systems, and winter grazing of stockpiled forages and corn crop residues by year-round system cows was managed by strip-stocking. Hay was fed to maintain a body condition score of 5 on a 9 point scale for spring-calving cows in both systems. Hay was supplemented as needed to maintain a body condition score of 3 for fall-calving cows nursing calves through the winter. Although initial condition scores for cows in both systems were different at the initiation of grazing for both winter and summer, there were no significant differences (P > .05) in overall condition score changes throughout both grazing seasons. In year 1, fall-calving cows in the year-round grazing system lost more (P < .05) body weight during winter than spring-calving cows in either system. In year 2, there were no differences seen in weight changes over winter for any group of cows. Average daily gains of fall calves in the yearround system were 1.9 lbs/day compared with weight gains of 2.5 lbs/day for spring calves from both systems. Yearly growing animal production from pastures for both years did not differ between systems when weight gains of stockers that grazed summer pastures in the year-round grazing system were added to weight gains of suckling calves. Carcass characteristics for all calves finished in the feedlot for both systems were similar. There were no significant differences in hay production between systems for year 1; however, amounts of hay needed to maintain cows were 923, 1373, 4732 lbs dry matter/cow for year-round fall-calving, year-round spring-calving, and minimal land spring-calving cows, respectively. In year 2, hay production per acre in the minimal land system was greater (P < .05) than for the year-round system, but the amounts of hay required per cow were 0, 0, and 4720 lbs dry matter/cow for yearround fall-calving, year-round spring-calving, and minimal land spring-calving cows, respectively.