Financial evaluation of the production and sale of Eucalyptus globulus Labill sawn wood made with a circular and band saw

Introducción. La necesidad de conocer la situación económica de dos unidades productoras de madera aserrada, que cuentan con una capacidad productiva ya instalada, motivó a desarrollar esta valoración financiera del rendimiento en el proceso de transformación de madera en rollo a madera escuadrada de Eucalyptus globulus, con el uso de sierra circular (aserradero A1) y sierra circular más sierra de cinta (aserradero A2). Objetivos. Establecer los costos de producción y la rentabilidad por la venta de tablas de primera, tablas de segunda y costeras con base en los sistemas de aserrío utilizados. Metodología. En esta investigación se aplicó las técnicas de observación y entrevista. Los costos se estimaron al agrupar los componentes; producción, administración, el nivel de ventas y financiero. La rentabilidad con el cálculo del margen bruto de utilidad (MBU) y margen de utilidad neta (MUN). Resultados. Los resultados evidencian costos de producción similares al momento de elaborar tablas de primera, tablas de segunda y costeras de E. globulus con valores de 0,29 y 0,27 USD/pt en los aserraderos A1 y A2 respectivamente. Por su parte, con la transacción de los tres productos de madera, generan utilidad bruta de 53,79%, 61,49% y como margen de utilidad neta 61 y 87 dólares respectivamente. Conclusión La rentabilidad de los dos proyectos de aserradero por vender tablas de primera, tablas de segunda y costeras de eucalipto generaron valores de margen de utilidad bruta superiores al 50%, idóneos para estos negocios, y en el caso del margen de utilidad neta del aserradero A2 por ser más alto con 26 USD, es el mejor en referencia al aserradero A1.Introduction. The need to know the economic situation of two production units of sawn wood, which have a production capacity already installed, motivated to develop this financial assessment of the performance in the process of transformation of round wood to square wood of Eucalyptus globulus, with the use of circular saw (sawmill A1) and circular saw plus band saw (sawmill A2). Objectives. Establish production costs and profitability for the sale of first, second and coastal boards based on the sawing systems used. Methodology. In this research observation and interview techniques were applied. The costs were estimated by grouping the components; production, administration, sales and financial level. The profitability with the calculation of gross profit margin (MBU) and net profit margin (MUN). Results. The results show similar production costs when preparing first, second and coastal tables of E. globulus with values ​​of 0.29 and 0.27 USD / pt in sawmills A1 and A2 respectively. On the other hand, with the transaction of the three wood products, they generate a gross profit of 53.79%, 61.49% and as a net profit margin of 61 and 87 dollars respectively. Conclusion. The profitability of the two sawmill projects for selling first-class, second-class and coastal Eucalyptus boards generated gross profit margin values ​​higher than 50%, ideal for these businesses, and in the case of the sawmill A2 net profit margin As it is the highest at 26 USD, it is the best in reference to the A1 sawmill

Silica-Copper Oxide Composite Thin Films as Solar Selective Coatings Prepared by Dipping Sol Gel

Silica-copper oxide (silica-CuO) composite thin films were prepared by a dipping sol-gel route using ethanolic solutions comprised TEOS and a copper-propionate complex. Sols with different TEOS/Cu-propionate (Si/Cu) molar ratios were prepared and applied on stainless steel substrates using dipping process. During the annealing process, copper-propionate complexes developed into particulate polycrystalline CuO dispersed in a partially crystallized silica matrix, as indicated by the X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses. The gel thermal analysis revealed that the prepared material might be stable up to 400°C. The silica-CuO/stainless steel system was characterized as a selective absorber surface and its solar selectivity parameters, absorptance (α), and emittance (ε) were evaluated from UV-NIR reflectance data. The solar parameters of such a system were mostly affected by the thickness and phase composition of the SiO2-CuO film. Interestingly, the best solar parameters (α = 0.92 and ε = 0.2) were associated to the thinnest films, which comprised a CuO-Cu2O mixture immersed in the silica matrix, as indicated by XPS

Participation of the <i>Salmonella</i> OmpD Porin in the Infection of RAW264.7 Macrophages and BALB/c Mice

<div><p><i>Salmonella</i> Typhimurium is the etiological agent of gastroenteritis in humans and enteric fever in mice. Inside these hosts, <i>Salmonella</i> must overcome hostile conditions to develop a successful infection, a process in which the levels of porins may be critical. Herein, the role of the <i>Salmonella</i> Typhimurium porin OmpD in the infection process was assessed for adherence, invasion and proliferation in RAW264.7 mouse macrophages and in BALB/c mice. In cultured macrophages, a Δ<i>ompD</i> strain exhibited increased invasion and proliferation phenotypes as compared to its parental strain. In contrast, overexpression of <i>ompD</i> caused a reduction in bacterial proliferation but did not affect adherence or invasion. In the murine model, the Δ<i>ompD</i> strain showed increased ability to survive and replicate in target organs of infection. The <i>ompD</i> transcript levels showed a down-regulation when <i>Salmonella</i> resided within cultured macrophages and when it colonized target organs in infected mice. Additionally, cultured macrophages infected with the Δ<i>ompD</i> strain produced lower levels of reactive oxygen species, suggesting that down-regulation of <i>ompD</i> could favor replication of <i>Salmonella</i> inside macrophages and the subsequent systemic dissemination, by limiting the reactive oxygen species response of the host.</p></div

Effect of OmpD in the proliferation of <i>S</i>. Typhimurium inside macrophages.

<p>Murine RAW 264.7 macrophages were infected (MOI of 100∶1) with <i>S</i>. Typhimurium 14028 s, and its Δ<i>ompD</i>, Δ<i>ompW</i> and Δ<i>ssrB</i> derivative mutants, containing or not the pBAD vector, or the plasmids pBAD-<i>ompD</i> or pBAD-<i>ompW</i> that overexpress OmpD and OmpW, respectively. CFU of the different strains were determined after recovery from infected macrophages at the indicated time points. The relative percentage of invasion at 2 h post infection (A) and of proliferation at 6, 8 and 12 h post infection (B) was determined to analyze the effect of the absence of <i>ompD</i>, <i>ompW</i> or <i>ssrB</i> genes. The relative percentage of proliferation at 6 (C), 8 (D) and 12 h (E) post infection was determined to analyze the effect of the absence and overexpression of OmpD. The relative percentage of proliferation at 12 h (F) post infection was determined to analyze the effect of the absence and overexpression of OmpW. Asterisks represent significant statistical difference between 14028 s and mutants used in this study (* <i>p</i>≤0.05). Values are mean ± SD.</p

Effect of OmpD in systemic infection.

<p>(A) Bacteremia assays. Groups of six BALB/c mice were orally inoculated with 10³ bacteria of strains 14028 s, Δ<i>ompD</i> or Δ<i>ompW</i> (n = 6). CFU/ml were determined from samples of peripheral blood obtained after 3 and 5 days post infection. Values are mean ± SD. Asterisks represent statistical significant differences (T-test, * <i>p</i>≤0.05). (B to G) CI assays. A mixture (1∶1 ratio) of 10³ bacteria of strains 14028 s (WT) and Δ<i>ompD</i> (B and E), Δ<i>ompW</i> (C and F) or Δ<i>ssrB</i> (D and G) was orally (B, C and D) or intraperitoneally (E, F and G) inoculated to groups of six BALBc mice (n = 6). Liver and spleen were extracted from mice 5 days post infection and the CFU per g of organ was determined for the wild-type strain and the respective mutant. Each data point represents the competitive index (CI), which is the ratio of mutant/WT of recovered CFU/g tissue in the respective organ from each mouse. Horizontal bars represent the median values of ratios for the organ type.</p

Expression of <i>S.</i> Typhimurium 14028 s <i>ompD</i> inside macrophages.

<p>Transcript levels of <i>ompD</i> (A) and <i>ompW</i> (B) from strain 14028 s were quantified by qRT-PCR by recovering total RNA from the infected macrophages at 1 to 12 h post infection, and from bacteria of the inoculating culture (I). Experiments were performed in triplicate. Asterisks represent significant statistical differences between the control and mutants strains (* <i>p</i>≤0.05; ** <i>p</i>≤0.005;*** <i>p</i>≤0.001). Values are mean ± SD.</p

Bacterial strains used in this study.

<p>Bacterial strains used in this study.</p

Intracellular levels of total ROS in RAW 264.7 macrophages infected and similarity between OmpD and other members of the OMP superfamily.

<p>(A) Total ROS were determined at 1 to 12 h post infection in macrophages infected with strains 14028 s and Δ<i>ompD</i> using the oxidant-sensitive probe H2DCFDA (fluorescence adjusted per µg of total protein of the sample). Asterisks represent statistical significant differences (* p≤0.05). A.U.  =  arbitrary units. (B) Sequence similarity network of OmpD and its closest homologues in the Omp superfamily. Nodes represent protein sequences, and edges represent worst reciprocal blastp E-values that are higher than a given threshold. Visualization was performed using the organic layout in Cytoscape 2.8.3 [Cline et al. 2007]. Reviewed proteins from Uniprot that have evidence of existing at the protein level are shown in color. Squares correspond to proteins that have known crystal structures in the Protein Data Bank. Edges filtered to e-value <1e-14, median alignment length: 341 residues, median identity: 34.0%. (C) Electrostatic surface potential of the biological assemblies of OmpD and SLAM-recognized proteins OmpC and OmpF. c.1) Periplasmic loops are mapped into the molecular surface: L1 blue, L2 red, L3 violet, L4 orange, L5 yellow, L6 ochre, L7 green and L8 Pink; c.2) Calculated surface electrostatic potential of OmpF from <i>Salmonella</i> Typhi (PDB: 3nsg); OmpF from <i>E. coli</i> (PDB:2zfg); OmpC from <i>Salmonella</i> Typhi (PDB: 3uu2) and OmpC from <i>E. coli</i> (PDB:2j1n) contoured at +- 2.0 kT.</p

<i>ompD</i> expression in target organs from BALB/c mice infected with <i>S.</i> Typhimurium 14028 s.

<p>Bacteria were recovered from organs (liver and spleen) after three and five days post infection. The <i>ompD</i> (A) and <i>ompW</i> (B) transcript levels were measured by qRT-PCR and are indicated as relative transcript levels with respect to the levels of each gene in the bacterial inoculum (I) used for infecting mice (n = 3). Experiments were performed in biological and technical triplicate. Asterisks represent statistical differences between control and treated cells (* <i>p</i>≤0.05; *** <i>p</i>≤0.001). Values are mean ± SD.</p