Search

In the design of sandwich panels with cellular cores for energy absorption, the geometrical effect of the cellular core design has not been investigated in details previously. In this work three cellular core designs, including re-entrant auxetic, octet-truss, and BCC lattice, were experimentally investigated for their performance under low-energy impact as sandwich structures. Samples with different cellular core designs were fabricated by laser sintering additive manufacturing process using Nylon 12 as material, and evaluated by drop weight testing under multiple strikes and at two levels of elevated temperatures (93 °C and 121 °C). It was found that beside relative densities, the geometrical design of the cellular cores could also significantly influence the impact energy absorption performance of the sandwich structures. It was also found that the impact energy absorption of the cellular structures investigated in this study does not have a significant correlation with either the quasi-static mechanical properties or the temperature. In addition, the auxetic cellular structure exhibits optimal overall energy absorption performance compared to both the octet-truss and the BCC lattice. [ABSTRACT FROM AUTHOR]

The question of whether carbon dioxide enhanced oil recovery (CO 2 -EOR) constitutes a valid alternative for greenhouse gas emission reduction has been frequently asked by the general public and environmental sectors. Through this technology, operational since 1972, oil production is enhanced by injecting CO 2 into depleted oil reservoirs in order displace the residual oil toward production wells in a solvent/miscible process. For decades, the CO 2 utilized for EOR has been most commonly sourced from natural CO 2 accumulations. More recently, a few projects have emerged where anthropogenic CO 2 (A-CO 2 ) is captured at an industrial facility, transported to a depleted oil field, and utilized for EOR. If carbon geologic storage is one of the project objectives, all the CO 2 injected into the oil field for EOR could technically be stored in the formation. Even though the CO 2 is being prevented from entering the atmosphere, and permanently stored away in a secured geologic formation, a question arises as to whether the total CO 2 volumes stored in order to produce the incremental oil through EOR are larger than the CO 2 emitted throughout the entire CO 2 -EOR process, including the capture facility, the EOR site, and the refining and burning of the end product. We intend to answer some of these questions through a DOE-NETL funded study titled “Carbon Life Cycle Analysis of CO 2 -EOR for Net Carbon Negative Oil (NCNO) Classification”. NCNO is defined as oil whose carbon emissions to the atmosphere, when burned or otherwise used, are less than the amount of carbon permanently stored in the reservoir in order to produce the oil. In this paper, we focus on the EOR site in what is referred to as a gate-to-gate system, but are inclusive of the burning of the refined product, as this end member is explicitly stated in the definition of NCNO. Finally, we use Cranfield, Mississippi, as a case study and come to the conclusion that the incremental oil produced is net carbon negative. [ABSTRACT FROM AUTHOR]

Abstract: Facebook is not only a virtual space to commune with the living, it is also a place to honor, memorialize, and engage in dialogs with the deceased. This study examines 550 memorial pages on Facebook for age, gender, race, and cause of death of the memorialized, as well as to whom the communication is addressed. Where ritualistic memorials and mourning practices usually occur in cemeteries or at the sites of accidents, memorial sites on Facebook offer an alternative space to mourn that is public, collective, and with archival capabilities. Individual dialogs and memories in this alternative space are not private, and often involve direct communications with the deceased. In this way, the dead never really die; rather perpetually remain in a digital state of dialogic limbo. [Copyright &y& Elsevier]

Abstract: The protozoan parasite Trypanosoma cruzi is the etiological agent of Chagas disease. To date, no vaccine is available for protection against T. cruzi infection. The CD8+ T cells immune response against specific antigens has shown to efficiently control the spread of the parasite in murine experimental infection. However, data concerning CD8+ response in Chagas patients are still restricted to a few epitopes. We have studied the existence of immunodominant CD8+ T cell epitopes in the paraflagellar rod proteins 2 and 3 (PFR2 and PFR3) from T. cruzi in a mouse model, and analyzed their recognition by cytotoxic T lymphocytes from Chagas disease patients. Immunization of C57BL/6-A2/Kb transgenic mice with plasmids coding for the fusion proteins PFR2-HSP70 and PFR3-HSP70 induced a specific CTL response against two PFRs epitopes (PFR2449–457 and PFR3481–489), and showed specific lysis percentages of 24 and 12, respectively. Moreover, the PFR219–28, PFR2156–163, PFR2449–457, PFR3428–436, PFR3475–482 and PFR3481–489 peptides were observed to have a high binding affinity to the HLA-A*02:01 molecule. Remarkably, these HLA-A*02:01-binding peptides are successfully processed and presented during natural infection by T. cruzi in the context of MHC class I as evidenced by using peptide-pulsed K562-A2 cells as antigen presenting cells. The T cells from Chagas disease chronic patients specific for PFR2/PFR3 selected CD8+ epitopes showed a pro-inflammatory cytokine secretion profile (IFN-γ, TNF-α and IL-6). A positive Granzime B secretion was observed in three out of 16 patients in response to PFR2156–163 and PFR2449–457 peptides, two out of 11 patients in response to PFR219–28 peptide and one out of 14 and 11 patients in response to PFR3428–436 and PFR3481–489 peptides, respectively. The PFRs-specific cytotoxic activity in purified PBMC was only detected in patients in the indeterminate phase of the disease. [Copyright &y& Elsevier]

Abstract: CD8+ cytotoxic T lymphocyte (CTL) response is critical for controlling the infection of the protozoan parasite Trypanosoma cruzi, the causative agent of Chagas disease. Since only a few CD8 antigens have been described in Chagas disease patients, the identification of new class I-restricted epitopes is urgently needed for the development of immunotherapies against T. cruzi infection. In this study, bioinformatic methods were used to predict HLA-A∗02:01-binders, and 30 peptides were selected, synthesized and tested for HLA-A∗02:01 binding. Among them, sixteen peptides with medium-to-high affinity were assayed for their recognition by CTL from HSP70-immunized or T. cruzi-infected transgenic B6-A2/Kb mice. Our results show that four immunodominant epitopes (HSP70210–8, HSP70255–63, HSP70316–24 and HSP70345−53) are contained in the T. cruzi HSP70 antigen. Indeed two of them (HSP70210–8 and HSP70316–24) were also recognized by CTL of HLA-A∗02:01+ Chagas disease patients, indicating that these peptides are processed and displayed as MHC class I epitopes during the natural history of T. cruzi infection. The HLA-A∗02:01 restriction was evidenced using peptide-pulsed K562-A2 cells as antigen-presenting cells. Both cytotoxic and cytokine-secreting activities were detected in response to the former two peptides and, moreover, 10/12 patients (83%) recognized at least one of these two HSP70-derived CD8+ epitopes. [Copyright &y& Elsevier]

• Anti- Leishmania antibodies can be detected in saliva of dogs. • After experimental infection they appear in serum before saliva. • Anti- Leishmania IgG2 showed better diagnostic value than anti- Leishmania IgA. • Anti- Leishmania antibodies in saliva showed higher inter-individual variation. The quantification of anti- Leishmania antibodies in serum and saliva by a time-resolved immunofluorometric assay is useful for the diagnosis and treatment monitoring of dogs with clinical leishmaniasis. We compared the kinetics of anti- Leishmania IgG2 and IgA antibodies in serum and saliva from 11 Beagle dogs experimentally infected with Leishmania infantum. Most dogs showed detectable concentrations of anti- Leishmania IgG2 earlier in serum (between 3 and 4 months p.i.) than in saliva (between 4 and 6 months p.i.). Overall, a high correlation between concentrations of anti- Leishmania IgG2 in serum and saliva (r = 0.853; P < 0.0001) was observed. The quantification of anti- Leishmania IgA showed less diagnostic value than IgG2, since detectable amounts of IgA were not observed in the saliva of four dogs and in the serum of one dog. In addition, a very low correlation between anti- Leishmania IgA in serum and saliva (r = 0.289; P < 0.001) was observed. Our results indicate that the antibodies against L. infantum in saliva appear approximately 1 month later than in serum, and suggest that there is a threshold for the passing of immunoglobulins from serum to saliva in dogs. These facts should be taken into consideration for a proper interpretation of saliva assays for quantification of antibodies. [ABSTRACT FROM AUTHOR]

• Anti- Leishmania IgG2 and IgA in serum and saliva do not show circadian rhythm. • Antibody levels in saliva show a greater intra-individual variation than in serum. • Anti- Leishmania IgA levels in saliva are highly influenced by flow rate. In this study, the circadian rhythm of IgG2 and IgA specific antibodies in serum and saliva samples of 6 dogs experimentally infected with Leishmania infantum was assessed. Sampling was performed at 8.00, 12.00, 16.00, 20.00, and 00.00 h on two consecutive days. Anti- Leishmania antibody levels in serum were expressed without any correction, whereas in saliva were shown in different ways: without any correction, adjusted by protein concentration and corrected by the salivary flow rate. No significant differences in anti- Leishmania IgG2 antibody levels in serum and saliva samples with or without correction were found. Significant differences were found when anti- Leishmania IgA levels were corrected by the salivary flow rate. In addition, a greater intra-individual variation of antibody levels was observed in saliva than in serum. However, this variation did not modify the serological status of the dogs. Therefore, it could be concluded that there is no circadian rhythm in serum and saliva samples and sampling can be performed at any time of the day. [ABSTRACT FROM AUTHOR]