Automated condition monitoring of mill ball size distribution and grate open area

Grinding media in coarse grinding tumbling mills constitute the biggest consumable cost to a comminution processing plant, therefore it is critically important to minimize associated wear. Secondly, efficient grinding is dependent on tight control of the desired ball size distribution, or else optimum impact breakage cannot be assured. Despite the significance of minitoring ball size distribution for mill operation, no practically deployable systems are currently in industry use to measure it. This paper describes a new method for highly accurate, comprehensive, and rapid determination of ball size distribution.Accurate SAG and AG mill product size control is dependent on appropriate Grate Open Area dimensions. Wear of the grate hole edges or in the plate thickness results in an increase of the open area due to the tapered hole cross section, which can result in oversize product exiting the mill. Conversely, some grate castings feature peening of the edges during mill operation, thereby decreasing open area, and therefore preventing the desireed top size product from exiting the mill.SAG mill throughput requires grate holes to remain open or else throughput is restricted. Many grates in operation are pegged by grinding media to varying degrees of severity. This paper introduces a comprehensive, accurate and rapid method to measure and track the size and pegging status of each and all grate holes in situ, and therefore provides tracking information on the Open Area of a SAG mill. This enables operators to control the primary mill product size and therefore the opportunity to stabilize downstream processes

RF-Energized Intracoronary Guidewire to Enhance Bipolar Ablation of the Interventricular Septum: In-silico Feasibility Study

"This is an Accepted Manuscript of an article published by Taylor & Francis in International Journal of Hyperthermiaon [date of publication], available online: https://doi.org/10.1080/02656736.2018.1425487"[EN] Purpose: Although bipolar radiofrequency (RF) ablation (RFA) is broadly used to eliminate ventricular tachycardias in the interventricular septum wall, it can fail to create transmural lesions in thick ventricular walls. To solve this problem, we explored whether an RF-energised guidewire inserted into the ventricular wall would enhance bipolar RFA in the creation of transmural lesions through the ventricular wall.Methods: We built three-dimensional computational models including two irrigated electrodes placed on opposing sides of the interventricular septum and a metal guidewire inserted into the septum. Computer simulations were conducted to compare the temperature distributions obtained with two ablation modes: bipolar mode (RF power delivered between both irrigated electrode) and time-division multiplexing (TDM) technique, which consists of activating the bipolar mode for 90% of the time and applying RF power between the guidewire and both irrigated electrodes during the remaining time.Results: The TDM technique was the most suitable in terms of creating wider lesions through the entire ventricular wall, avoiding the hour-glass shape of thermal lesions associated with the bipolar mode. This was especially apparent in the case of thick walls (15mm). Furthermore, the TDM technique was able to create transmural lesions even when the guidewire was displaced from the midplane of the wall.Conclusions: An RF-energised guidewire could enhance bipolar RFA by allowing transmural lesions to be made through thick ventricular walls. However, the safety of this new approach must be assessed in future pre-clinical studies, especially in terms of the risk of stenosis and its clinical impact.This work was supported by the Spanish Ministerio de Economia, Industria y Competitividad under "Plan Estatal de Investigacion, Desarrollo e Innovacion Orientada a los Retos de la Sociedad" Grant "TEC2014-52383-C3 (TEC2014-52383-C3-1-R)". A. Gonzalez-Suarez has a "Juan de la Cierva-formacion" Postdoctoral Grant (FJCI-2015-27202) supported by the Spanish Ministerio de Economia, Industria y Competitividad, Secretaria de Estado de Investigacion, Desarrollo e Innovacion.Pérez, JJ.; González Suárez, A.; D Avila, A.; Berjano, E. (2018). RF-Energized Intracoronary Guidewire to Enhance Bipolar Ablation of the Interventricular Septum: In-silico Feasibility Study. International Journal of Hyperthermia. 34(8):1202-1212. https://doi.org/10.1080/02656736.2018.1425487S12021212348Baszko, A., Telec, W., Kałmucki, P., Iwachów, P., Kochman, K., Szymański, R., … Siminiak, T. (2016). Bipolar irrigated radiofrequency ablation of resistant ventricular tachycardia with a septal intramural origin: the initial experience and a description of the method. Clinical Case Reports, 4(10), 957-961. doi:10.1002/ccr3.648Gizurarson, S., Spears, D., Sivagangabalan, G., Farid, T., Ha, A. C. T., Masse, S., … Nanthakumar, K. (2014). Bipolar ablation for deep intra-myocardial circuits: human ex vivo development and in vivo experience. Europace, 16(11), 1684-1688. doi:10.1093/europace/euu001Koruth, J. S., Dukkipati, S., Miller, M. A., Neuzil, P., d’ Avila, A., & Reddy, V. Y. (2012). Bipolar irrigated radiofrequency ablation: A therapeutic option for refractory intramural atrial and ventricular tachycardia circuits. Heart Rhythm, 9(12), 1932-1941. doi:10.1016/j.hrthm.2012.08.001Baldinger, S. H., Kumar, S., Barbhaiya, C. R., Mahida, S., Epstein, L. M., Michaud, G. F., … Stevenson, W. G. (2015). Epicardial Radiofrequency Ablation Failure During Ablation Procedures for Ventricular Arrhythmias. Circulation: Arrhythmia and Electrophysiology, 8(6), 1422-1432. doi:10.1161/circep.115.003202Santangeli, P., Shaw, G. C., & Marchlinski, F. E. (2017). Radiofrequency Wire Facilitated Interventricular Septal Access for Catheter Ablation of Ventricular Tachycardia in a Patient With Aortic and Mitral Mechanical Valves. Circulation: Arrhythmia and Electrophysiology, 10(1). doi:10.1161/circep.116.004771Berjano, E. J., Hornero, F., Atienza, F., & Montero, A. (2003). Long electrodes for radio frequency ablation: comparative study of surface versus intramural application. Medical Engineering & Physics, 25(10), 869-877. doi:10.1016/s1350-4533(03)00125-5McLELLAN, A. J. A., ELLIMS, A. H., PRABHU, S., VOSKOBOINIK, A., ILES, L. M., HARE, J. L., … KISTLER, P. M. (2016). Diffuse Ventricular Fibrosis on Cardiac Magnetic Resonance Imaging Associates With Ventricular Tachycardia in Patients With Hypertrophic Cardiomyopathy. Journal of Cardiovascular Electrophysiology, 27(5), 571-580. doi:10.1111/jce.12948Berjano, E. J. (2006). Theoretical modeling for radiofrequency ablation: state-of-the-art and challenges for the future. BioMedical Engineering OnLine, 5(1). doi:10.1186/1475-925x-5-24Pérez, J. J., González-Suárez, A., & Berjano, E. (2017). Numerical analysis of thermal impact of intramyocardial capillary blood flow during radiofrequency cardiac ablation. International Journal of Hyperthermia, 34(3), 243-249. doi:10.1080/02656736.2017.1336258Labonte, S. (1994). Numerical model for radio-frequency ablation of the endocardium and its experimental validation. IEEE Transactions on Biomedical Engineering, 41(2), 108-115. doi:10.1109/10.284921Doss, J. D. (1982). Calculation of electric fields in conductive media. Medical Physics, 9(4), 566-573. doi:10.1118/1.595107PÉREZ, J. J., D’AVILA, A., ARYANA, A., & BERJANO, E. (2015). Electrical and Thermal Effects of Esophageal Temperature Probes on Radiofrequency Catheter Ablation of Atrial Fibrillation: Results from a Computational Modeling Study. Journal of Cardiovascular Electrophysiology, 26(5), 556-564. doi:10.1111/jce.12630Jo, B., & Aksan, A. (2010). Prediction of the extent of thermal damage in the cornea during conductive keratoplasty. Journal of Thermal Biology, 35(4), 167-174. doi:10.1016/j.jtherbio.2010.02.004Gonzalez-Suarez, A., & Berjano, E. (2016). Comparative Analysis of Different Methods of Modeling the Thermal Effect of Circulating Blood Flow During RF Cardiac Ablation. IEEE Transactions on Biomedical Engineering, 63(2), 250-259. doi:10.1109/tbme.2015.2451178WINTERFIELD, J. R., JENSEN, J., GILBERT, T., MARCHLINSKI, F., NATALE, A., PACKER, D., … WILBER, D. J. (2015). Lesion Size and Safety Comparison Between the Novel Flex Tip on the FlexAbility Ablation Catheter and the Solid Tips on the ThermoCool and ThermoCool SF Ablation Catheters. Journal of Cardiovascular Electrophysiology, 27(1), 102-109. doi:10.1111/jce.12835PÉREZ, J. J., D’AVILA, A., ARYANA, A., TRUJILLO, M., & BERJANO, E. (2016). Can Fat Deposition After Myocardial Infarction Alter the Performance of RF Catheter Ablation of Scar-Related Ventricular Tachycardia?: Results from a Computer Modeling Study. Journal of Cardiovascular Electrophysiology, 27(8), 947-952. doi:10.1111/jce.13006Haines, D. E. (2011). Letter by Haines Regarding Article, «Direct Measurement of the Lethal Isotherm for Radiofrequency Ablation of Myocardial Tissue». Circulation: Arrhythmia and Electrophysiology, 4(5). doi:10.1161/circep.111.965459González-Suárez, A., Trujillo, M., Koruth, J., d’ Avila, A., & Berjano, E. (2014). Radiofrequency cardiac ablation with catheters placed on opposing sides of the ventricular wall: Computer modelling comparing bipolar and unipolar modes. International Journal of Hyperthermia, 30(6), 372-384. doi:10.3109/02656736.2014.949878Gianni, C., Mohanty, S., Trivedi, C., Di Biase, L., Al-Ahmad, A., Natale, A., & David Burkhardt, J. (2017). Alternative Approaches for Ablation of Resistant Ventricular Tachycardia. Cardiac Electrophysiology Clinics, 9(1), 93-98. doi:10.1016/j.ccep.2016.10.006Boll, D. T., Lewin, J. S., Duerk, J. L., & Merkle, E. M. (2003). Do Surgical Clips Interfere with Radiofrequency Thermal Ablation? American Journal of Roentgenology, 180(6), 1557-1560. doi:10.2214/ajr.180.6.1801557Eung Je Woo, Tungjitkusolmun, S., Hong Cao, Jang-Zem Tsai, Webster, J. G., Vorperian, V. R., & Will, J. A. (2000). A new catheter design using needle electrode for subendocardial RF ablation of ventricular muscles: finite element analysis and in vitro experiments. IEEE Transactions on Biomedical Engineering, 47(1), 23-31. doi:10.1109/10.817616BLOUIN, L. T., & MARCUS, F. I. (1989). The Effect of Electrode Design on the Efficiency of Delivery of Radiofrequency Energy to Cardiac Tissue In Vitro. Pacing and Clinical Electrophysiology, 12(1), 136-143. doi:10.1111/j.1540-8159.1989.tb02640.xTao, W., Jian-ping, G., Xu, H., Wen-sheng, L., Liang, C., Guo-ping, C., … Jin-hua, S. (2013). The effects of endovenous radiofrequency ablation on coagulation and the vein wall in an experimental canine model. Vascular, 21(4), 215-219. doi:10.1177/1708538113478762Badham, G. E., Strong, S. M., & Whiteley, M. S. (2014). An in vitro study to optimise treatment of varicose veins with radiofrequency-induced thermo therapy. Phlebology: The Journal of Venous Disease, 30(1), 17-23. doi:10.1177/0268355514552005Kreidieh, B., Rodríguez-Mañero, M., A. Schurmann, P., Ibarra-Cortez, S. H., Dave, A. S., & Valderrábano, M. (2016). Retrograde Coronary Venous Ethanol Infusion for Ablation of Refractory Ventricular Tachycardia. Circulation: Arrhythmia and Electrophysiology, 9(7). doi:10.1161/circep.116.00435

A meta-analysis of gene expression signatures of blood pressure and hypertension

Genome-wide association studies (GWAS) have uncovered numerous genetic variants (SNPs) that are associated with blood pressure (BP). Genetic variants may lead to BP changes by acting on intermediate molecular phenotypes such as coded protein sequence or gene expression, which in turn affect BP variability. Therefore, characterizing genes whose expression is associated with BP may reveal cellular processes involved in BP regulation and uncover how transcripts mediate genetic and environmental effects on BP variability. A meta-analysis of results from six studies of global gene expression profiles of BP and hypertension in whole blood was performed in 7017 individuals who were not receiving antihypertensive drug treatment. We identified 34 genes that were differentially expressed in relation to BP (Bonferroni-corrected p<0.05). Among these genes, FOS and PTGS2 have been previously reported to be involved in BP-related processes; the others are novel. The top BP signature genes in aggregate explain 5%-9% of inter-individual variance in BP. Of note, rs3184504 in SH2B3, which was also reported in GWAS to be associated with BP, was found to be a trans regulator of the expression of 6 of the transcripts we found to be associated with BP (FOS, MYADM, PP1R15A, TAGAP, S100A10, and FGBP2). Gene set enrichment analysis suggested that the BP-related global gene expression changes include genes involved in inflammatory response and apoptosis pathways. Our study provides new insights into molecular mechanisms underlying BP regulation, and suggests novel transcriptomic markers for the treatment and prevention of hypertension.Tianxiao Huan, Tõnu Esko, Marjolein J. Peters, Luke C. Pilling, Katharina Schramm, Claudia Schurmann, Brian H. Chen, Chunyu Liu, Roby Joehanes, Andrew D. Johnson, Chen Yao, Sai-xia Ying, Paul Courchesne, Lili Milani, Nalini Raghavachari, Richard Wang, Poching Liu, Eva Reinmaa, Abbas Dehghan, Albert Hofman, André G. Uitterlinden, Dena G. Hernandez, Stefania Bandinelli, Andrew Singleton, David Melzer, Andres Metspalu, Maren Carstensen, Harald Grallert, Christian Herder, Thomas Meitinger, Annette Peters, Michael Roden, Melanie Waldenberger, Marcus Dörr, Stephan B. Felix, Tanja Zeller, International Consortium for Blood Pressure GWAS, ICBP, Ramachandran Vasan, Christopher J. O'Donnell, Peter J. Munson, Xia Yang, Holger Prokisch, Uwe Völker, Joyce B. J. van Meurs, Luigi Ferrucci, Daniel Lev

Different HLA-DRB1 allele distributions in distinct clinical subgroups of sarcoidosis patients

<p>Abstract</p> <p>Background</p> <p>A strong genetic influence by the MHC class II region has been reported in sarcoidosis, however in many studies with different results. This may possibly be caused by actual differences between distinct ethnic groups, too small sample sizes, or because of lack of accurate clinical subgrouping.</p> <p>Subjects and methods</p> <p>In this study we HLA typed a large patient population (n = 754) recruited from one single centre. Patients were sub-grouped into those with Löfgren's syndrome (LS) (n = 302) and those without (non-Löfgren's) (n = 452), and the majority of them were clinically classified into those with recovery within two years (resolving) and those with signs of disease for more than two years (non-resolving). PCR was used for determination of HLA-DRB1 alleles. Swedish healthy blood donors (n = 1366) served as controls.</p> <p>Results</p> <p>There was a dramatic difference in the distribution of HLA alleles in LS compared to non-LS patients (p = 4 × 10^-36). Most notably, DRB1*01, DRB1*03 and DRB1*14, clearly differed in LS and non-LS patients. In relation to disease course, DRB1*07, DRB1*14 and DRB1*15 generally associated with, while DRB1*01 and DRB1*03 protected against, a non-resolving disease. Interestingly, the clinical influence of DRB1*03 (good prognosis) dominated over that of DRB1*15 (bad prognosis).</p> <p>Conclusions</p> <p>We found several significant differences between LS and non-LS patients and we therefore suggest that genetic association studies in sarcoidosis should include a careful clinical characterisation and sub-grouping of patients, in order to reveal true genetic associations. This may be particularly accurate to do in the heterogeneous non-LS group of patients.</p

Thermography imaging during static and controlled thermoregulation in complex regional pain syndrome type 1: diagnostic value and involvement of the central sympathetic system

BACKGROUND: Complex Regional Pain Syndrome type 1 (CRPS1) is a clinical diagnosis based on criteria describing symptoms of the disease. The main aim of the present study was to compare the sensitivity and specificity of calculation methods used to assess thermographic images (infrared imaging) obtained during temperature provocation. The secondary objective was to obtain information about the involvement of the sympathetic system in CRPS1. METHODS: We studied 12 patients in whom CRPS1 was diagnosed according to the criteria of Bruehl. High and low whole body cooling and warming induced and reduced sympathetic vasoconstrictor activity. The degree of vasoconstrictor activity in both hands was monitored using a videothermograph. The sensitivity and specificity of the calculation methods used to assess the thermographic images were calculated. RESULTS: The temperature difference between the hands in the CRPS patients increases significantly when the sympathetic system is provoked. At both the maximum and minimum vasoconstriction no significant differences were found in fingertip temperatures between both hands. CONCLUSION: The majority of CRPS1 patients do not show maximal obtainable temperature differences between the involved and contralateral extremity at room temperature (static measurement). During cold and warm temperature challenges this temperature difference increases significantly. As a result a higher sensitivity and specificity could be achieved in the diagnosis of CRPS1. These findings suggest that the sympathetic efferent system is involved in CRPS1

Genome-wide association study of primary open-angle glaucoma in continental and admixed African populations.

Primary open angle glaucoma (POAG) is a complex disease with a major genetic contribution. Its prevalence varies greatly among ethnic groups, and is up to five times more frequent in black African populations compared to Europeans. So far, worldwide efforts to elucidate the genetic complexity of POAG in African populations has been limited. We conducted a genome-wide association study in 1113 POAG cases and 1826 controls from Tanzanian, South African and African American study samples. Apart from confirming evidence of association at TXNRD2 (rs16984299; OR[T] 1.20; P = 0.003), we found that a genetic risk score combining the effects of the 15 previously reported POAG loci was significantly associated with POAG in our samples (OR 1.56; 95% CI 1.26-1.93; P = 4.79 × 10-5). By genome-wide association testing we identified a novel candidate locus, rs141186647, harboring EXOC4 (OR[A] 0.48; P = 3.75 × 10-8), a gene transcribing a component of the exocyst complex involved in vesicle transport. The low frequency and high degree of genetic heterogeneity at this region hampered validation of this finding in predominantly West-African replication sets. Our results suggest that established genetic risk factors play a role in African POAG, however, they do not explain the higher disease load. The high heterogeneity within Africans remains a challenge to identify the genetic commonalities for POAG in this ethnicity, and demands studies of extremely large size

Mendelian randomization indicates causal effects of estradiol levels on kidney function in males

ContextChronic kidney disease (CKD) is a public health burden worldwide. Epidemiological studies observed an association between sex hormones, including estradiol, and kidney function.ObjectiveWe conducted a Mendelian randomization (MR) study to assess a possible causal effect of estradiol levels on kidney function in males and females.DesignWe performed a bidirectional two-sample MR using published genetic associations of serum levels of estradiol in men (n = 206,927) and women (n = 229,966), and of kidney traits represented by estimated glomerular filtration rate (eGFR, n = 567,460), urine albumin-to-creatinine ratio (UACR, n = 547,361), and CKD (n = 41,395 cases and n = 439,303 controls) using data obtained from the CKDGen Consortium. Additionally, we conducted a genome-wide association study using UK Biobank cohort study data (n = 11,798 men and n = 6,835 women) to identify novel genetic associations with levels of estradiol, and then used these variants as instruments in a one-sample MR.ResultsThe two-sample MR indicated that genetically predicted estradiol levels are significantly associated with eGFR in men (beta = 0.077; p = 5.2E-05). We identified a single locus at chromosome 14 associated with estradiol levels in men being significant in the one-sample MR on eGFR (beta = 0.199; p = 0.017). We revealed significant results with eGFR in postmenopausal women and with UACR in premenopausal women, which did not reach statistical significance in the sensitivity MR analyses. No causal effect of eGFR or UACR on estradiol levels was found.ConclusionsWe conclude that serum estradiol levels may have a causal effect on kidney function. Our MR results provide starting points for studies to develop therapeutic strategies to reduce kidney disease