424 research outputs found

    Refractory Ceramics Synthesis by Solid-State Reaction Between CaCO3 (Mollusk Shell) And Al2O3 Powders

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    Calcium aluminate-based refractory ceramic was developed as an innovative refractory material, using garden snail (Helix aspersa) shells as a natural source of CaCO3. A 1:1 molar ratio mixture of CaC O3 from snail shells and commercial Al2O3 powder was prepared by means of high-energy mechanical milling. The mixed powder was compacted in cylindrical samples (disks) and consolidated by sintering at 1450°C and 1500°C for 1h. The density and porosity were evaluated using the Archimedes principle, while the mechanical properties (hardness, fracture toughness, and shear modulus) were determined by indentation and ultrasonic methods, respectively. The thermal shock resistance was tested by heating samples to temperatures between 900 and 1400°C and subsequent quenching in water at room temperature. X-ray diffraction patterns of sintered samples indicate the formation of different calcium aluminate phases, such as CaAl12O (krotite/monoclinic),CaAl4O7 (grossite/monoclinic) and CaAl2O (hibonite-5H/hexagonal). The fracture toughness and shear modulus values of materials sintered at 1450°C were higher (0.48 MPa•m1/2)) and 59 GPa, respectively than those of materials sintered at 1500°C (0.43 MPa•m1/ 2 and 55 GPa, respectively). Also changes in the bulk density, hardness and thermal shock resistance values were observed in materials sintered at 1450°C and 1500°C

    Return to Play (RTP) y aspectos psicológicos asociados : una revisión sistemática

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    El objetivo es examinar las investigaciones que tratan la asociación entre el Return to Play (RTP) y factores psicológicos en población deportista. Se realizó una búsqueda sistemática siguiendo las indicaciones de la guía PRISMA. Como palabras clave se usaron: return to play and sport and psycho* and injur*. Como base de datos se uso "Web of Science". Como criterios de inclusión: 1) abordar al menos una variable psicológica, 2) ser de carácter empírico y 3) no ser validación de un instrumento. Se obtuvieron 70 artículos, reducidos a 29. Los resultados muestran relación directa entre la influencia de los factores psicológicos y el tiempo y calidad que el deportista emplea en la rehabilitación y retoma el deporte. El tiempo empleado en la rehabilitación y la retirada temprana del deportista de su deporte tras la lesión parecen ser determinantes para el correcto RTP. Se discute la importancia de comprender los aspectos psicosociales que forman parte del proceso de rehabilitación. Igualmente, el miedo a una nueva lesión, el nivel deportivo previo a la lesión, los rasgos de personalidad y la disposición psicológica para volver a jugar desempeñan un rol muy importante para el RTP.This review aim to examine the researches that address the association between Return to Play (RTP) and psychological factors in athletes. To this end, a systematic review of the literature was conducted, taking in consideration PRISMA guidelines. As keywords were used: return to play and sport and psycho* and injur*. Base data used were "Web of Science". Inclusion criteria were: 1) address at least one psychological variable, 2) to be empirical investigation and 3) not to be a validation. 70 articles were obtained, which were reduced to 29. The results show a direct relationship between the influence of psychological factors and the time and quality that the athlete uses in rehabilitation and return to play. The time spent in rehabilitation and the early withdrawal of the athlete from his activity after the injury seems to be decisive for the correct RTP. The importance of understanding the psychosocial aspects that are part of the rehabilitation process is discussed. The fear of a re-injury, the sport level prior to the injury, the personality traits and the psychological disposition to play again were very important for the RTP.O objetivo é examinar a pesquisa que trata da associação entre o Return to Play (RTP) e fatores psicológicos na população esportiva. Uma busca sistemática foi realizada seguindo as indicações do guia PRISMA. Como palavras-chave foram usadas: return to play e sport e psycho * e injur *. Foi pesquisado em "Web of Science". Como critérios de inclusão: 1) abordar pelo menos uma variável psicológica, 2) ser empírico e 3) não validar um instrumento. Foram obtidos 70 artigos, reduzidos a 29. Os resultados mostram uma relação direta entre a inuência dos fatores psicológicos e o tempo e a qualidade que o atleta utiliza na reabilitação e retoma o esporte. O tempo gasto na reabilitação e a retirada precoce do atleta após a lesão parecem ser decisivos para o RTP correto. A importância de compreender os fatores psicossociais que fazem parte do processo de reabilitação é discutida. Da mesma forma, o medo de re-lesão, o nível de esporte antes da lesão, os traços de personalidade e a disposição psicológica de jogar novamente desempenham um papel muito importante para a RTP

    Genesis and evolution of the San Manuel iron skarn deposit (Betic Cordillera, SW Spain)

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    The San Manuel magnesian skarn is an iron deposit hosted in dolomitic marbles from a tectonic slice imbricated within the Ronda peridotites, in the westernmost part of the Betic Cordillera, Spain. According to the dominant mineral assemblage, the skarn is subdivided into three different zones, (1) forsterite +/- calcite skarn, (2) calcite +/- chlorite +/- serpentine skarn, and (3) Ca-amphibole skarn. The main ore in the skarn is a similar to 2.5 m thick, massive ore body situated in the middle of the sequence. In this paper, we firstly report a comprehensive major to trace element composition, texture, microstructure, and mineralogy characterization for zoned magnesioferritemagnetite grains of the San Manuel deposit using a combination of (1) laser ablation inductively coupled plasma mass spectrometer, (2) focused ion beam combined with transmission electron microscopy, and (3) electron back-scattered diffraction. We have defined four different magnesioferrite-magnetite generations. A complete sequence of zoning includes cores of magnesioferrite (Mag-1; MgO up to 10.6 wt%) overprinted by three successive generations of magnetite, namely Mag-2, Mag-3, Mag-4. Mag-2 (MgO < 4 wt%), hosts composite forsterite +/- calcite +/- chlorite inclusions, consistently with high Si, Ca, and Sr (average: 8204 ppm, 8980 ppm, and 49 ppm respectively) contents detected by in situ laser ablation inductively coupled plasma (LA-ICP-MS). Mag-3 replacing former Mag-1 and Mag-2 includes nanometric spinel and gahnite exsolutions detected by focused ion beam combined with a transmission electron microscope (FIB-TEM), which is consistent with its high Al, Ti, V, and Ga (average: 5073 ppm, 368 ppm, and 20 ppm, respectively) trace element concentration. Mag-4 is the Fe-richest magnetite (up to 94.16 wt% FeOtotal) forming the outermost rims in magnetite grains, and exhibiting the lowest total trace element contents. Approaches in temperature estimations employing magnetitespinel exsolutions in Mag-3 suggest that the minimum temperature of the prograde stage reached temperatures below 700 degrees C, whereas Mag-4 should be formed during the retrograde stage. Magnetite microstructure studied by electron backscatter diffraction (EBSD) suggests Mag-4 formation under fluid-assisted dynamic conditions, which is consistent with the tectonic evolution of the emplacement. We propose that the San Manuel deposit formed by pulsed hydrothermal fluids derived from anatexis of crustal rocks during peridotite emplacement, promoting reequilibration processes that led to the magnesioferrite-magnetite zoning

    C1-2 transarticular screw fixation combined with Gallie technique in atloaxial dislocation

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    Introducción: existen múltiples técnicas quirúrgicas para tratar la inestabilidad del complejo atlantoaxial. La fijación con tornillos transarticulares C1-2 (técnica de Magerl) ha mostrado altos índices de fusión, y puede ser combinada con los sistemas de alambrado descritos inicialmente, para garantizar mayor estabilidad al constructo.Presentación de caso: masculino, 62 años, que luego de una caída de dos metros, es traído a la institución con dolor cervical y con imposibilidad para mover las extremidades. Al examen neurológico, presentaba un grado B en la American Spinal Injury Classiffication Scale. Se diagnostica fractura odontoidea conminuta y luxación atloaxoidea. Se le aplica tracción cervical con lo que se logra la alineación vertebral. Se planifica tratamiento quirúrgico mediante técnica de Magerl. Ante trayectoria subóptima del tornillo inicial, se combina con fusión atloaxoidea posterior, mediante técnica de Gallie. Se mantuvo inmovilización externa durante dos semanas. Al egreso hospitalario, el paciente logra la deambulación, aunque con disparesia braquial con predominio distal. En estudios radiológicos evolutivos, no se observa fallo del sistema de instrumentación.Conclusiones: en este caso la utilización de la técnica de Gallie, ante la malposición de uno de los tornillos transarticulares C1-2, permitió conservar la estabilidad del constructo. Introduction: Multiple surgical techniques exist to treat instability of the atlantoaxial complex. Transarticular C1-2 screw fixation (Magerl's technique) has shown high fusion rates, and can be combined with the initially described wiring systems to guarantee greater stability to the construct.Case presentation: male, 62 years old, who after a two-meter fall, was brought to the institution reporting cervical pain and inability to move the limbs. On neurological examination, he had a grade B on the American Spinal Injury Classiffication Scale. A comminuted odontoid fracture and atloaxial dislocation were diagnosed. Cervical traction was applied and vertebral alignment was achieved. Surgical treatment was planned using Magerl's technique. Given the suboptimal trajectory of the initial screw, it was combined with posterior atloaxoid fusion, using Gallie technique. External immobilization was maintained for two weeks. At hospital discharge, the patient achieved ambulation, maintaining brachial dysparesis with distal predominance. In evolutionary radiological studies, no failure of the instrumentation system was observed.Conclusions: In our case, the use of the Gallie technique, in view of the malposition of one of the C1-2 transarticular screws, allowed preserving the stability of the construct

    Which came first: The disease or the pest? Is there a host mediated spread of Beauveria bassiana (Ascomycota: Hypocreales) by invasive palm pests?

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    The red palm weevil (RPW) Rhynchophorus ferrugineus (Olivier) (Coleoptera: Curculionidae) is threatening the palm family worldwide, causing important economic losses. Current tactics to manage the weevil are largely based on chemical control, although the use of pesticides is hampered by several environmental constraints. Since the first introduction of RPW in Spain in 1996 and during its progressive spread around the Mediterranean basin, the number of reports of natural infection of RPW populations by entomopathogenic fungi (EPF) has been rising for 15 years, and this rise could support a pest-mediated EPF spread. To challenge this hypothesis, we assessed the usefulness of the region of elongation factor 1-alpha (EF1-alpha), Bloc nuclear intergenic region (Bloc) and inter simple sequence repeat (ISSR) markers, alone or in combination, to infer the relationships among Mediterranean Beauveria and Metarhizium strains isolated from the RPW. Second, the effect of abiotic factors, such as temperature, humidity and UV-B radiation, on the germination and growth of these EPFs strains as a function of their genealogy and geographic origin were determined. Finally, the pathogenicity of strains from different genetic clades was evaluated against larvae and adults of R. ferrugineus. The phylogenetic analysis based on the EF-1 alpha gene identified eight different sequences among 24 fungal isolates of four fungal species. Similar clades were clustered when Bloc and ISSR analyses were performed. The results showed that strains of different origins were clustered in the same Glade, and this outcome could be explained by an RPW-mediated EPF spread that was also influenced by time, geographical and other RPW related factors. Neither the response to abiotic factors nor virulence to RPW larvae and adults were related to the sequence type, with all B. bassiana strains well adapted to Mediterraneam climatic conditions. Taken together, these findings may help to select the best strain for RPW management

    Genetically Confirmed Familial Hypercholesterolemia in Patients With Acute Coronary Syndrome

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    BACKGROUND: Genetic screening programs in unselected individuals with increased levels of low-density lipoprotein cholesterol (LDL-C) have shown modest results in identifying individuals with familial hypercholesterolemia (FH). OBJECTIVES: This study assessed the prevalence of genetically confirmed FH in patients with acute coronary syndrome (ACS) and compared the diagnostic performance of FH clinical criteria versus FH genetic testing. METHODS: Genetic study of 7 genes (LDLR, APOB, PCSK9, APOE, STAP1, LDLRAP1, and LIPA) associated with FH and 12 common alleles associated with polygenic hypercholesterolemia was performed in 103 patients with ACS, age ≤65 years, and LDL-C levels ≥160 mg/dl. Dutch Lipid Clinic (DLC) and Simon Broome (SB) FH clinical criteria were also applied. RESULTS: The prevalence of genetically confirmed FH was 8.7% (95% confidence interval [CI]: 4.3% to 16.4%; n = 9); 29% (95% CI: 18.5% to 42.1%; n = 18) of patients without FH variants had a score highly suggestive of polygenic hypercholesterolemia. The prevalence of probable to definite FH according to DLC criteria was 27.2% (95% CI: 19.1% to 37.0%; n = 28), whereas SB criteria identified 27.2% of patients (95% CI: 19.1% to 37.0%; n = 28) with possible to definite FH. DLC and SB algorithms failed to diagnose 4 (44%) and 3 (33%) patients with genetically confirmed FH, respectively. Cascade genetic testing in first-degree relatives identified 6 additional individuals with FH. CONCLUSIONS: The prevalence of genetically confirmed FH in patients with ACS age ≤65 years and with LDL-C levels ≥160 mg/dl is high (approximately 9%). FH clinical algorithms do not accurately classify patients with FH. Genetic testing should be advocated in young patients with ACS and high LDL-C levels to allow prompt identification of patients with FH and relatives at risk.This research was supported in part by the Instituto de Salud Carlos III (grants RD012/0042/0066 and CB16/11/00432), Spanish Ministry of Economy and Competitiveness (grant SAF2015-71863-REDT), and Alexion through an Investigator Initiated Research Grant. Grants from the Instituto de Salud Carlos III and the Spanish Ministry of Economy and Competitiveness are supported by the Plan Estatal de I+D+I 2013-2016 European Regional Development Fund (FEDER), "A way of making Europe." The sponsors played no role in the design, collection, analysis, or interpretation of the data or in the decision to submit the manuscript for publication. Drs. Castillo, Lluis-Ganella, and Quintana are employees of Gendiag.exe/Ferrer inCode.S

    Lymphocyte Profile and Immune Checkpoint Expression in Drug-Induced Liver Injury: An Immunophenotyping Study

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    The identification of specific HLA risk alleles in drug-induced liver injury (DILI) points toward an important role of the adaptive immune system in DILI development. In this study, we aimed to corroborate the role of an adaptive immune response in DILI through immunophenotyping of leukocyte populations and immune checkpoint expressions. Blood samples were collected from adjudicated DILI (n = 12), acute viral hepatitis (VH; n = 13), acute autoimmune hepatitis (AIH; n = 9), and acute liver injury of unknown etiology (n = 15) at day 1 (recognition), day 7, and day >30. Blood samples from patients with nonalcoholic fatty liver disease (NAFLD; n = 20) and healthy liver controls (HLCs; n = 54) were extracted at one time point. Leukocyte populations and immune checkpoint expressions were determined based on cell surface receptors, except for CTLA-4 that was determined intracellularly, using flow cytometry. At recognition, DILI demonstrated significantly higher levels of activated helper T-cell (P < 0.0001), activated cytotoxic T-cells (P = 0.0003), Th1 (P = 0.0358), intracellular CTLA-4 level in helper T-cells (P = 0.0192), and PD-L1 presenting monocytes (P = 0.0452) than HLC. These levels approached those of HLC over time. No significant differences were found between DILI and VH. However, DILI presented higher level of activated helper T-cells and CTLA-4 than NAFLD and lower PD-L1 level than AIH. Our findings suggest that an adaptive immune response is involved in DILI in which activated CD4+ and CD8+ play an important role. Increased expression of negative immune checkpoints is likely the effect of peripheral tolerance regulation.The present study has been supported by grants of Instituto de Salud Carlos III cofounded by Fondo Europeo de Desarrollo Regional – FEDER (contract numbers: PI19/00883, PI16/01748, P18-RT-3364-2020, and PT20/000127). CIBERehd and Plataforma ISCiii Ensayos Clínicos are funded by Instituto de Salud Carlos III. Funding for open access charge: Universidad de Málaga/CBUA. The funding sources had no involvement in the study design; in the collection, analysis, and interpretation of data; in the writing of the report, or in the decision to submit the manuscript for publication

    Intake and apparent digestibility of rations based on foliage of tropical leguminous trees, ammoniated rices straw, and corn byproducts for goats in confinement

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    The consumption and apparent digestibility of rations containing foliage of four arboreal legume species, Acacia macrantha (Am), A. tamarindifolia (At), A. glomerosa (Ag) and Leucaena leucocephala (Ll), in mixture with ammoniated rice straw (ARS) and corn byproducts meal (CBM), were evaluated using eight growing female Creole goats of mean body weights 20.5 kg, housed in metabolic stalls. The experimental design was an 8 x 8 latin square with a 4 x 2 factorial arrangement of the factors: 1) legume species and 2) level of foliage inclusion: 18.75 and 37.5% in the ration dry matter (DM). The experiment was divided into eight periods of 14 days each (7 for adaptation and 7 for measurement of consumption and total feces collection). The eight treatments (rations) included 25% (CBM) in all cases, and 56.25% ARS in combination with 18.75% foliage of Am, At, Ag, and Ll in T1, T3, T5 and T7; or 37.5% ARS in combination with 37.5% of the four respective legumes in T2, T4, T6, and T8. Rations containing AM (T1 + T2) and AG (T3 + T6) showed a tendency toward higher DM intake than T3 + T4 and T7 + T8 (1050 and 980 vs. 836 and 882 g/day), respectively, P&lt;0.1011). Digestibility results followed the same pattern for DM (82 and 83 vs. 77 and 80%, P&lt;0.008), fiber insoluble in acid detergent, and hemicellulose (HC). Rations with the lower level of legume combined, tended to give higher DM intake (987 vs. 889 g/day) and surpassed (P&lt;0.05) those with higher legume level in digestibility of all the chemical fractions mentioned except HC (Sp)

    Synergistic Antimicrobial Effects of Silver/Transition-metal Combinatorial Treatments

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    Due to the emergence of multi-drug resistant strains, development of novel antibiotics has become a critical issue. One promising approach is the use of transition metals, since they exhibit rapid and significant toxicity, at low concentrations, in prokaryotic cells. Nevertheless, one main drawback of transition metals is their toxicity in eukaryotic cells. Here, we show that the barriers to use them as therapeutic agents could be mitigated by combining them with silver. We demonstrate that synergism of combinatorial treatments (Silver/transition metals, including Zn, Co, Cd, Ni, and Cu) increases up to 8-fold their antimicrobial effect, when compared to their individual effects, against E. coli and B. subtilis. We find that most combinatorial treatments exhibit synergistic antimicrobial effects at low/ non-toxic concentrations to human keratinocyte cells, blast and melanoma rat cell lines. Moreover, we show that silver/(Cu, Ni, and Zn) increase prokaryotic cell permeability at sub-inhibitory concentrations, demonstrating this to be a possible mechanism of the synergistic behavior. Together, these results suggest that these combinatorial treatments will play an important role in the future development of antimicrobial agents and treatments against infections. In specific, the cytotoxicity experiments show that the combinations have great potential in the treatment of topical infections

    The U.S.-Mexico Border Infectious Disease Surveillance Project: Establishing Binational Border Surveillance

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    In 1997, the Centers for Disease Control and Prevention, the Mexican Secretariat of Health, and border health officials began the development of the Border Infectious Disease Surveillance (BIDS) project, a surveillance system for infectious diseases along the U.S.-Mexico border. During a 3-year period, a binational team implemented an active, sentinel surveillance system for hepatitis and febrile exanthems at 13 clinical sites. The network developed surveillance protocols, trained nine surveillance coordinators, established serologic testing at four Mexican border laboratories, and created agreements for data sharing and notification of selected diseases and outbreaks. BIDS facilitated investigations of dengue fever in Texas-Tamaulipas and measles in California–Baja California. BIDS demonstrates that a binational effort with local, state, and federal participation can create a regional surveillance system that crosses an international border. Reducing administrative, infrastructure, and political barriers to cross-border public health collaboration will enhance the effectiveness of disease prevention projects such as BIDS
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