Ultrafast-Contactless Flash Sintering using Plasma Electrodes

This paper presents a novel derivative of flash sintering, in which contactless flash sintering (CFS) is achieved using plasma electrodes. In this setup, electrical contact with the sample to be sintered is made by two arc plasma electrodes, one on either side, allowing current to pass through the sample. This opens up the possibility of continuous throughput flash sintering. Preheating, a usual precondition for flash sintering, is provided by the arc electrodes which heat the sample to 1400 °C. The best results were produced with pre-compacted samples (bars 1.8 mm thick) of pure B(4)C (discharge time 2s, current 4A) and SiC:B(4)C 50 wt% (3s at 6A), which were fully consolidated under a heating rate approaching 20000 °C/min. For the composite a cylindrical volume of 14 mm(3) was sintered to full density with limited grain growth

Improving tuberculosis diagnosis: Better tests or better healthcare?

In a Perspective accompanying Sylvia and colleagues, Carlton Evans and colleagues discuss the challenge of squaring policies around tuberculosis diagnosis with the realities of clinical practice in small villages and low-resource settings

Variations in the APOE allele or BDNF Val66Met polymorphism are not associated with changes in cognitive function following a tertiary education intervention in older adults: the Tasmanian Healthy Brain Project.

The apolipoprotein (APOE) ε4 allele and the Met variant of the brain-derived neurotrophic factor (BDNF) Val66Met polymorphism are associated with reduced cognitive function in older adults. The aim of this study was to examine the independent and interactional effect of the APOE ε4 allele and BDNF Val66Met polymorphism on cognitive function in a cohort of healthy older adults who had undertaken further university level education. Multiple group latent growth curve modeling revealed no change in cognitive function over time in APOE ε4-carriers or in BDNF Met-carriers, nor in carriers of both APOE-ε4 and BDNF-Met alleles. Further, the results indicate that allelic variation in either APOE or BDNF does not modify the beneficial effects of a university-based education intervention on cognitive function over a 4-year period following the intervention

Pulmonary dendritic cells and alveolar macrophages are regulated by γδ T cells during the resolution of S. pneumoniae-induced inflammation

γδ T cells commonly associate with mucosal and epithelial sites, fulfilling a variety of immunoregulatory functions. While lung γδ T cells have well-characterized pro-inflammatory activity, their potential role in the resolution of lung inflammation has yet to be explored in any detail. Indeed, given the importance of minimizing inflammation, the cellular mechanisms driving the resolution of lung inflammation are poorly understood. Using a murine model of acute Streptococcus pneumoniae-mediated lung inflammation, we now show that resolution of inflammation following bacterial clearance is associated with a > 30-fold increase in γδ T-cell number. Although inflammation eventually resolves in TCRδ−/− mice, elevated numbers of alveolar macrophages and pulmonary dendritic cells, and the appearance of well-formed granulomas in lungs of TCRδ−/− mice, together indicated a role for γδ T cells in regulating mononuclear phagocyte number. Ex vivo, both alveolar macrophages and pulmonary dendritic cells were susceptible to lung γδ T cell-mediated cytotoxicity, the first demonstration of such activity against a dendritic cell population. These findings support a model whereby expansion of γδ T cells helps restore mononuclear phagocyte numbers to homeostatic levels, protecting the lung from the consequences of inappropriate inflammation. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd

Why wait? The social determinants underlying tuberculosis diagnostic delay.

BACKGROUND: Early detection and diagnosis of tuberculosis remain major global priorities for tuberculosis control. Few studies have used a qualitative approach to investigate the social determinants contributing to diagnostic delay and none have compared data collected from individual, community, and health-system levels. We aimed to characterize the social determinants that contribute to diagnostic delay among persons diagnosed with tuberculosis living in resource-constrained settings. METHODS/PRINCIPLE FINDINGS: Data were collected in public health facilities with high tuberculosis incidence in 19 districts of Lima, Peru. Semi-structured interviews with persons diagnosed with tuberculosis (n = 105) and their family members (n = 63) explored health-seeking behaviours, community perceptions of tuberculosis and socio-demographic circumstances. Focus groups (n = 6) were conducted with health personnel (n = 35) working in the National Tuberculosis Program. All interview data were transcribed and analysed using a grounded theory approach. The median delay between symptom onset and the public health facility visit that led to the first positive diagnostic sample was 57 days (interquartile range 28-126). The great majority of persons diagnosed with tuberculosis distrusted the public health system and sought care at public health facilities only after exhausting other options. It was universally agreed that persons diagnosed with tuberculosis faced discrimination by public and health personnel. Self-medication with medicines bought at local pharmacies was reported as the most common initial health-seeking behaviour due to the speed and low-cost of treatment in pharmacies. Most persons diagnosed with tuberculosis initially perceived their illness as a simple virus. CONCLUSIONS: Diagnostic delay was common and prolonged. When individuals reached a threshold of symptom severity, they addressed their health with the least time-consuming, most economically feasible, and well-known healthcare option available to them. In high-burden settings, more human and material resources are required to promote tuberculosis case-finding initiatives, reduce tuberculosis associated stigma and address the social determinants underlying diagnostic delay

Sending Your Grandparents to University Increases Cognitive Reserve: The Tasmanian Healthy Brain Project.

Increasing an individual’s level of cognitive reserve (CR) has been suggested as a nonpharmacological approach to reducing the risk for Alzheimer’s disease. We examined changes in CR in older adults participating over 4 years in the Tasmanian Healthy Brain Project. Method: A sample of 459 healthy older adults between 50 and 79 years of age underwent a comprehensive annual assessment of current CR, neuropsychological function, and psychosocial factors over a 4-year period. The intervention group of 359 older adults (M � 59.61 years, SD � 6.67) having completed a minimum of 12 months part-time university study were compared against a control reference group of 100 adults (M � 62.49 years, SD � 6.24) who did not engage in further education. Results: Growth mixture modeling demonstrated that 44.3% of the control sample showed no change in CR, whereas 92.5% of the further education participants displayed a significant linear increase in CR over the 4 years of the study. These results indicate that older adults engaging in high-level mental stimulation display an increase in CR over a 4-year period. Conclusion: Increasing mental activity in older adulthood may be a viable strategy to improve cognitive function and offset cognitive decline associated with normal aging

Psychological interventions for acute psychiatric inpatients with schizophrenia-spectrum disorders: A systematic review and meta-analysis

BACKGROUND: Acute inpatient psychiatric wards are important yet challenging environments in which to implement psychological interventions for people with schizophrenia-spectrum disorders. No meta-analysis to date has evaluated whether psychological interventions are effective in this context. METHODS: We systematically searched Embase, Medline and PsycInfo databases for randomised controlled trials (RCTs) of psychological interventions implemented in acute inpatient psychiatric settings with individuals with schizophrenia-spectrum disorders. We conducted random effects meta-analyses of between-groups outcomes at post-intervention and relapse/re-hospitalisation rates by follow-up. RESULTS: Twenty-nine trials were suitable for meta-analysis. Psychological interventions improved post-intervention positive symptoms, social functioning and treatment compliance and reduced the risk of relapse/ re-hospitalisation, relative to control conditions. Analyses of specific intervention effects found positive effects of psychoeducation on several key outcomes (power > 80%) and preliminary evidence for positive effects of acceptance and commitment therapy (ACT), cognitive behaviour therapy (CBT) and metacognitive training (MCT) on some outcomes (power < 80%). CONCLUSION: Psychological interventions can be helpful for acute inpatients with schizophrenia-spectrum disorders. However, risk of bias was often high or unclear, and some analyses were underpowered. Further research should use more rigorous RCT designs and publish meta-analysable data on positive symptoms, general psychopathology, relapse/ re-hospitalisation, social functioning and treatment compliance

Flash Spark Plasma Sintering (FSPS) of Pure ZrB2

Export Date: 19 August 2014 CODEN: JACTA Correspondence Address: Reece, M.J.; School of Engineering and Material Science, Queen Mary University of London, London E1 4NS, United Kingdom; email: [email protected] Funding Details: EP/K008749/1, EPSRC, European Commission Funding Details: FP7 2007-2013, EC, European Commission References: Cologna, M., Rashkova, B., Raj, R., Flash Sintering of Nanograin Zirconia in <5 s at 850°C (2010) J. Am. Ceram. Soc., 93 (11), pp. 3556-3559; Downs, J.A., Sglavo, V.M., Electric Field Assisted Sintering of Cubic Zirconia at 390°C (2013) J. Am. Ceram. Soc., 96 (5), pp. 1342-1344; Muccillo, R., Muccillo, E.N.S., An Experimental Setup for Shrinkage Evaluation during Electric Field-Assisted Flash Sintering: Application to Yttria-Stabilized Zirconia (2013) J. Eur. Ceram. Soc., 33 (3), pp. 515-520; Muccillo, R., Muccillo, E.N.S., Electric Field-Assisted Flash Sintering of Tin Dioxide (2014) J. Eur. Ceram. Soc., 34 (4), pp. 915-923; Jha, S.K., Raj, R., The Effect of Electric Field on Sintering and Electrical Conductivity of Titania (2014) J. Am. Ceram. Soc., 97 (2), pp. 527-534; Zapata-Solvas, E., Bonilla, S., Wilshaw, P.R., Todd, R.I., Preliminary Investigation of Flash Sintering of SiC (2013) J. Eur. Ceram. Soc., 33 (1314), pp. 2811-2816; Grasso, S., Sakka, Y., Rendtorff, N., Hu, C., Maizza, G., Borodianska, H., Vasylkiv, O., Modeling of the Temperature Distribution of flash sintered Zirconia (2011) Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/J. Ceram. Soc. Jpn., 119 (1386), pp. 144-146; Park, J., Chen, I.W., In Situ Thermometry Measuring Temperature Flashes Exceeding 1,700°C in 8 mol% Y2O3-Stablized Zirconia under Constant-Voltage Heating (2013) J. Am. Ceram. Soc., 96 (3), pp. 697-700; Zapata-Solvas, E., Jayaseelan, D.D., Lin, H.T., Brown, P., Lee, W.E., Mechanical Properties of ZrB2- and HfB2-Based Ultra-High Temperature Ceramics Fabricated by Spark Plasma Sintering (2013) J. Eur. Ceram. Soc., 33 (7), pp. 1373-1386; Grasso, S., Sakka, Y., Maizza, G., Electric Current Activated/Assisted Sintering (ECAS): A Review of Patents 1906-2008 (2009) Sci. Technol. Adv. Mater., 10 (5), p. 053001; Mallik, M., Kailath, A.J., Ray, K.K., Mitra, R., Electrical and Thermophysical Properties of ZrB2 and HfB 2 Based Composites (2012) J. Eur. Ceram. Soc., 32 (10), pp. 2545-2555; Steil, M.C., Marinha, D., Aman, Y., Gomes, J.R.C., Kleitz, M., From Conventional Ac Flash-Sintering of YSZ to Hyper-Flash and Double Flash (2013) J. Eur. Ceram. Soc., 33 (11), pp. 2093-2101; Ortiz, A.L., Zamora, V., Rodríguez-Rojas, F., A Study of the Oxidation of ZrB2 Powders during High-Energy Ball-Milling in Air (2012) Ceram. Int., 38 (4), pp. 2857-2863; Porwal, H., Tatarko, P., Grasso, S., Hu, C., Boccaccini, A.R., Dlouhý, I., Reece, M., Toughened and Machinable Glass Matrix Composites Reinforced with Graphene and Graphene-Oxide Nano Platelets (2013) Sci. Technol. Adv. Mater., 14, p. 055007 Pure ZrB2 powder was Flash sintered in an SPS furnace (FSPS). The samples were densified up to 95.0% in 35 s under an applied pressure of 16 MPa. Compared to Conventional SPS (CSPS), the newly developed FSPS technique resulted in an unprecedented energy and time savings of about 95% and 98% respectively. ZrB2 monoliths obtained by CSPS and FSPS were compared with respect to microstructures, densification behavior, and grain growth. The developed methodology might find application to a wide range of highly conductive ceramics as such refractory borides and carbides. © 2014 The American Ceramic Society.Export Date: 19 August 2014 CODEN: JACTA Correspondence Address: Reece, M.J.; School of Engineering and Material Science, Queen Mary University of London, London E1 4NS, United Kingdom; email: [email protected] Funding Details: EP/K008749/1, EPSRC, European Commission Funding Details: FP7 2007-2013, EC, European Commission References: Cologna, M., Rashkova, B., Raj, R., Flash Sintering of Nanograin Zirconia in <5 s at 850°C (2010) J. Am. Ceram. Soc., 93 (11), pp. 3556-3559; Downs, J.A., Sglavo, V.M., Electric Field Assisted Sintering of Cubic Zirconia at 390°C (2013) J. Am. Ceram. Soc., 96 (5), pp. 1342-1344; Muccillo, R., Muccillo, E.N.S., An Experimental Setup for Shrinkage Evaluation during Electric Field-Assisted Flash Sintering: Application to Yttria-Stabilized Zirconia (2013) J. Eur. Ceram. Soc., 33 (3), pp. 515-520; Muccillo, R., Muccillo, E.N.S., Electric Field-Assisted Flash Sintering of Tin Dioxide (2014) J. Eur. Ceram. Soc., 34 (4), pp. 915-923; Jha, S.K., Raj, R., The Effect of Electric Field on Sintering and Electrical Conductivity of Titania (2014) J. Am. Ceram. Soc., 97 (2), pp. 527-534; Zapata-Solvas, E., Bonilla, S., Wilshaw, P.R., Todd, R.I., Preliminary Investigation of Flash Sintering of SiC (2013) J. Eur. Ceram. Soc., 33 (1314), pp. 2811-2816; Grasso, S., Sakka, Y., Rendtorff, N., Hu, C., Maizza, G., Borodianska, H., Vasylkiv, O., Modeling of the Temperature Distribution of flash sintered Zirconia (2011) Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/J. Ceram. Soc. Jpn., 119 (1386), pp. 144-146; Park, J., Chen, I.W., In Situ Thermometry Measuring Temperature Flashes Exceeding 1,700°C in 8 mol% Y2O3-Stablized Zirconia under Constant-Voltage Heating (2013) J. Am. Ceram. Soc., 96 (3), pp. 697-700; Zapata-Solvas, E., Jayaseelan, D.D., Lin, H.T., Brown, P., Lee, W.E., Mechanical Properties of ZrB2- and HfB2-Based Ultra-High Temperature Ceramics Fabricated by Spark Plasma Sintering (2013) J. Eur. Ceram. Soc., 33 (7), pp. 1373-1386; Grasso, S., Sakka, Y., Maizza, G., Electric Current Activated/Assisted Sintering (ECAS): A Review of Patents 1906-2008 (2009) Sci. Technol. Adv. Mater., 10 (5), p. 053001; Mallik, M., Kailath, A.J., Ray, K.K., Mitra, R., Electrical and Thermophysical Properties of ZrB2 and HfB 2 Based Composites (2012) J. Eur. Ceram. Soc., 32 (10), pp. 2545-2555; Steil, M.C., Marinha, D., Aman, Y., Gomes, J.R.C., Kleitz, M., From Conventional Ac Flash-Sintering of YSZ to Hyper-Flash and Double Flash (2013) J. Eur. Ceram. Soc., 33 (11), pp. 2093-2101; Ortiz, A.L., Zamora, V., Rodríguez-Rojas, F., A Study of the Oxidation of ZrB2 Powders during High-Energy Ball-Milling in Air (2012) Ceram. Int., 38 (4), pp. 2857-2863; Porwal, H., Tatarko, P., Grasso, S., Hu, C., Boccaccini, A.R., Dlouhý, I., Reece, M., Toughened and Machinable Glass Matrix Composites Reinforced with Graphene and Graphene-Oxide Nano Platelets (2013) Sci. Technol. Adv. Mater., 14, p. 055007 Pure ZrB2 powder was Flash sintered in an SPS furnace (FSPS). The samples were densified up to 95.0% in 35 s under an applied pressure of 16 MPa. Compared to Conventional SPS (CSPS), the newly developed FSPS technique resulted in an unprecedented energy and time savings of about 95% and 98% respectively. ZrB2 monoliths obtained by CSPS and FSPS were compared with respect to microstructures, densification behavior, and grain growth. The developed methodology might find application to a wide range of highly conductive ceramics as such refractory borides and carbides. © 2014 The American Ceramic Society.S.G. was supported by EPSRC (EP/K008749/1, XMat). T.S. was supported by EC FP7 2007-2013 (ADMACOM). O.C. was supported by CONACYT (Consejo Nacional de Ciencia y Tecnología, México)