Inheritance of resistance to white mold disease in Phaseolus coccineus

A white-seeded selection of Phaseolus coccineus (P.I. 175829) from Turkey was found to be highly resistant to Whetzelinia screcotiorum. Intraspecilic crosses and backcrosses made with susceptible Phaseolus vulgaris germplasm indicate that a single completely dominant gene governs this high level of resistance. The symbol Ws is proposed for this gene. The inoculation procedure used to evaluate bean germplasm simulated natural disease occurrence in commercial bean fields. Plants at the susceptible blossom stage were sprayed with a suspension of ascospores obtained from aseptically produced apothecia. Immediately after inoculation, plants were placed in a mist chamber at 21-25°C for one week before final evaluatio

Ray-based description of normal mode amplitudes in a range-dependent waveguide

An analogue of the geometrical optics for description of the modal structure of a wave field in a range-dependent waveguide is considered. In the scope of this approach the mode amplitude is expressed through solutions of the ray equations. This analytical description accounts for mode coupling and remains valid in a nonadiabatic environment. It has been used to investigate the applicability condition of the adiabatic approximation. An applicability criterion is formulated as a restriction on variations of the action variable of the ray.Comment: 11 pages, 5 figure

Transcatheter heart valve selection and permanent pacemaker implantation in patients with pre-existent right bundle branch block

Background-Right bundle branch block is an established predictor for new conduction disturbances and need for a permanent pacemaker (PPM) after transcatheter aortic valve replacement. The aim of the study was to evaluate the absolute rates of transcatheter aortic valve replacement related PPM implantations in patients with pre-existent right bundle branch block and categorize for different transcatheter heart valves. Methods and Results-We pooled data on 306 transcatheter aortic valve replacement patients from 4 high-volume centers in Europe and selected those with right bundle branch block at baseline without a previously implanted PPM. Logistic regression was used to evaluate whether PPM rate differed among transcatheter heart valves after adjustment for confounders. Mean age was 83±7 years and 63% were male. Median Society of Thoracic Surgeons score was 6.3 (interquartile range, 4.1-10.2). The following transcatheter valve designs were used: Medtronic CoreValve (n=130; Medtronic, Minneapolis, MN); Edwards Sapien XT (ES-XT; n=124) and Edwards Sapien 3 (ES-3; n=32; Edwards Lifesciences, Irvine, CA); and Boston Scientific Lotus (n=20; Boston Scientific Corporation, Marlborough, MA). Overall permanent pacemaker implantation rate post-transcatheter aortic valve replacement was 41%, and per valve design: 75% with Lotus, 46% with CoreValve, 32% with ES-XT, and 34% with ES-3. The indication for PPM implantation was total atrioventricular block in 98% of the cases. Lotus was associated with a higher PPM rate than all other valves. PPM rate did not differ between ES-XT and ES-3. Ventricular paced rhythm at 30-day and 1-year follow-up was present in 81% at 89%, respectively. Conclusions-Right bundle branch block at baseline is associated with a high incidence of PPM implantation for all transcatheter heart valves. PPM rate was highest for Lotus and lowest for ES-XT and ES-3. Pacemaker dependency remained high during followup

Estimation of total collagen volume: a T1 mapping versus histological comparison study in healthy Landrace pigs

Right ventricular biopsy represents the gold standard for the assessment of myocardial fibrosis and collagen content. This invasive technique, however, is accompanied by perioperative complications and poor reproducibility. Extracellular volume (ECV) measured through cardiovascular magnetic resonance (CMR) has emerged as a valid surrogate method to assess fibrosis non-invasively. Nonetheless, ECV provides an overestimation of collagen concentration since it also considers interstitial space. Our study aims to investigate the feasibility of estimating total collagen volume (TCV) through CMR by comparing it with the TCV measured at histology. Seven healthy Landrace pigs were acutely instrumented closed-chest and transported to the MRI facility for measurements. For each protocol, CMR imaging at 3T was acquired. MEDIS software was used to analyze T1 mapping and ECV for both the left ventricular myocardium (LVmyo) and left ventricular septum (LVseptum). ECV was then used to estimate TCVCMR at LVmyo and LVseptum following previously published formulas. Tissues were prepared following an established protocol and stained with picrosirius red to analyze the TCVhisto in LVmyo and LVseptum. TCV measured at LVmyo and LVseptum with both histology (8 ± 5 ml and 7 ± 3 ml, respectively) and T1-Mapping (9 ± 5 ml and 8 ± 6 ml, respectively) did not show any regional differences. TCVhisto and TCVCMR showed a good level of data agreement by Bland–Altman analysis. Estimation of TCV through CMR may be a promising way to non-invasively assess myocardial collagen content and may be useful to track disease progression or treatment response

PATOGENICIDADE DE ESPÉCIES DE Macrophomina COLETADAS DE PLANTAS DANINHAS EM FEIJÃO-CAUPI

[PT] A podridão de carvão causada por Macrophomina phaseolina é uma das principais doenças do feijão-caupi, causando perdas substanciais para os produtores. Na região semiárida do Brasil, o feijão-caupi é uma das alternativas utilizadas para rotação de culturas durante a entressafra do melão. Isso favorece a multiplicação de Macrophomina, uma vez que ambas as culturas são hospedeiras desse patógeno. O objetivo deste estudo foi verificar a patogenicidade em caupi de Macrophomina phaseolina e M. pseudophaseolina em caupi. Isolados de Macrophomina spp. obtidos das raízes de Trianthema portulacastrum e Boerhavia diffusa, espécies de plantas daninhas prevalentes em áreas de produção de melão no Nordeste brasileiro foram utilizadas neste estudo. O experimento foi realizado em casa de vegetação. Plantas de feijão-caupi 'Paulistinha' foram inoculados com 30 isolados de M. phaseolina, 30 isolados de M. pseudophaseolina e um isolado de referência de M. phaseolina obtido de raízes de feijão-caupi. Todos os isolados de Macrophomina foram patogênicos ao feijão-caupi, não havendo diferenças estatísticas entre as duas espécies de Macrophomina em relação à incidência e severidade da doença. Além disso, 65,2 e 100,0% dos isolados de M. phaseolina, e 56,2 e 92,8% dos isolados de M. pseudophaseolina, obtidos de T. portulacastrum e B. diffusa, respectivamente, foram tão severos ao feijão-caupi quanto o isolado de referência. Esses resultados enfatizam a necessidade de estabelecer práticas de manejo visando o controle de T. portucalastrum e B. diffusa nas áreas de produção de feijão-caupi, pois podem atuar como fontes de inóculo e sobrevivência para Macrophomina spp.[EN] Charcoal rot caused by Macrophomina phaseolina is a major cowpea disease causing substantial losses to growers. In the semi-arid region of Brazil, cowpea is one of the most widely used alternatives for crop rotation during the off-season of melon. This favors Macrophomina multiplication because both crops are hosts of this pathogen. The objective of this study was to verify the pathogenicity of Macrophomina phaseolina and M. pseudophaseolina on cowpea. The Macrophomina spp. isolates used were obtained from the roots of Trianthema portulacastrum and Boerhavia diffusa, weed species prevalent in melon production areas in North-east Brazilian The experiment was carried out in a greenhouse. Cowpea plants cv. Paulistinha' were inoculated with 30 M. phaseolina isolates, 30 M. pseudophaseolina isolates and a reference isolate of H. phaseolina obtained from cowpea roots. All Macrophomina isolates were able to cause disease on cowpea and there were no statistical differences between both Macrophomina species regarding disease incidence and severity. Moreover, 65.2 and 100.0% of the M. phaseolina isolates, and 56.2 and 92.8% of the M. pseudophaseolina isolates, obtained from T. portulacastrum and B. diffusa, respectively, were as severe to cowpea as the M. phaseolina reference isolate from cowpea. These results emphasize the need to establish management practices aiming to control T. portucalastrum and B. diffusa from cowpea production areas, as they can act as potential sources of inoculum and survival for Macrophomina spp.This study was partially financed by the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior -Brazil (CAPES) -Finance Code 001 and by the Conselho Nacional de desenvolvimento Cientifico e Tecnologico (CNPq).Sales Jr., R.; Nogueira, A.; Mitsa Paiva Negreiros, A.; Rodrigues, T.; De Queiroz, M.; Armengol Fortí, J. (2020). PATHOGENICITY OF Macrophomina SPECIES COLLECTED FROM WEEDS IN COWPEA. Revista Caatinga. 33(2):395-401. https://doi.org/10.1590/1983-21252020v33n212rcS395401332Ambrósio, M. M. Q., Dantas, A. C. A., Martínez-Perez, E., Medeiros, A. C., Nunes, G. H. S., & Picó, M. B. (2015). Screening a variable germplasm collection of Cucumis melo L. for seedling resistance to Macrophomina phaseolina. Euphytica, 206(2), 287-300. doi:10.1007/s10681-015-1452-xFreitas, F. C. L., Medeiros, V. F. L. P., Grangeiro, L. C., Silva, M. G. O., Nascimento, P. G. M. L., & Nunes, G. H. (2009). Interferência de plantas daninhas na cultura do feijão-caupi. Planta Daninha, 27(2), 241-247. doi:10.1590/s0100-83582009000200005Gomes-Silva, F., Almeida, C. M. A., Silva, A. G., Leão, M. P. C., Silva, K. P., Oliveira, L. G., … Lima, V. L. M. (2017). Genetic Diversity of Isolates of Macrophomina phaseolina Associated with Cowpea from Brazil Semi-Arid Region. Journal of Agricultural Science, 9(11), 112. doi:10.5539/jas.v9n11p112Gupta, G. K., Sharma, S. K., & Ramteke, R. (2012). Biology, Epidemiology and Management of the Pathogenic Fungus Macrophomina phaseolina (Tassi) Goid with Special Reference to Charcoal Rot of Soybean (Glycine max (L.) Merrill). Journal of Phytopathology, 160(4), 167-180. doi:10.1111/j.1439-0434.2012.01884.xKaur, S., Dhillon, G. S., Brar, S. K., Vallad, G. E., Chand, R., & Chauhan, V. B. (2012). Emerging phytopathogenMacrophomina phaseolina: biology, economic importance and current diagnostic trends. Critical Reviews in Microbiology, 38(2), 136-151. doi:10.3109/1040841x.2011.640977Machado, A. R., Pinho, D. B., Soares, D. J., Gomes, A. A. M., & Pereira, O. L. (2018). Bayesian analyses of five gene regions reveal a new phylogenetic species of Macrophomina associated with charcoal rot on oilseed crops in Brazil. European Journal of Plant Pathology, 153(1), 89-100. doi:10.1007/s10658-018-1545-1Mbaye, N., Mame, P. S., Ndiaga, C., & Ibrahima, N. (2015). Is the recently described Macrophomina pseudophaseolina pathogenically different from Macrophomina phaseolina? African Journal of Microbiology Research, 9(45), 2232-2238. doi:10.5897/ajmr2015.7742Negreiros, A. M. P., Sales Júnior, R., León, M., Melo, N. J., Michereff, S. J., Ambrósio, M. M., … Armengol, J. (2019). Identification and pathogenicity of Macrophomina species collected from weeds in melon fields in Northeastern Brazil. Journal of Phytopathology, 167(6), 326-337. doi:10.1111/jph.12801Negreiros, A. M. P., Júnior, R. S., Rodrigues, A. P. M. S., León, M., & Armengol, J. (2019). Prevalent weeds collected from cucurbit fields in Northeastern Brazil reveal new species diversity in the genusMonosporascus. Annals of Applied Biology, 174(3), 349-363. doi:10.1111/aab.12493Ramos, H. M. M., Bastos, E. A., Andrade Júnior, A. S. de, & Marouelli, W. A. (2012). Estratégias ótimas de irrigação do feijão‑caupi para produção de grãos verdes. Pesquisa Agropecuária Brasileira, 47(4), 576-583. doi:10.1590/s0100-204x2012000400014Reis, E. M., Boaretto, C., & Danelli, A. L. D. (2014). Macrophomina phaseolina: density and longevity of microsclerotia in soybean root tissues and free on the soil, and competitive saprophytic ability. Summa Phytopathologica, 40(2), 128-133. doi:10.1590/0100-5405/1921Rocha, M. de M., Carvalho, K. J. M. de, Freire Filho, F. R., Lopes, Â. C. de A., Gomes, R. L. F., & Sousa, I. da S. (2009). Controle genético do comprimento do pedúnculo em feijão-caupi. Pesquisa Agropecuária Brasileira, 44(3), 270-275. doi:10.1590/s0100-204x2009000300008Sales Junior, R., Oliveira, O. F. de, Medeiros, É. V. de, Guimarães, I. M., Correia, K. C., & Michereff, S. J. (2012). Ervas daninhas como hospedeiras alternativas de patógenos causadores do colapso do meloeiro. Revista Ciência Agronômica, 43(1), 195-198. doi:10.1590/s1806-66902012000100024Sales Júnior, R., Rodrigues, A. P. M. dos S., Negreiros, A. M. P., Ambrósio, M. M. de Q., Barboza, H. da S., & Beltrán, R. (2019). WEEDS AS POTENTIAL HOSTS FOR FUNGAL ROOT PATHOGENS OF WATERMELON. Revista Caatinga, 32(1), 1-6. doi:10.1590/1983-21252019v32n101rcFrancisco, de A. S. e S., & Carlos, A. V. de A. (2016). The Assistat Software Version 7.7 and its use in the analysis of experimental data. African Journal of Agricultural Research, 11(39), 3733-3740. doi:10.5897/ajar2016.11522Silva, M. G. O. da, Freitas, F. C. L. de, Negreiros, M. Z. de, Mesquita, H. C. de, Santana, F. A. O. de, & Lima, M. F. P. de. (2013). Manejo de plantas daninhas na cultura da melancia nos sistemas de plantio direto e convencional. Horticultura Brasileira, 31(3), 494-499. doi:10.1590/s0102-05362013000300025Zhao, L., Cai, J., He, W., & Zhang, Y. (2019). Macrophomina vaccinii sp. nov. causing blueberry stem blight in China. MycoKeys, 55, 1-14. doi:10.3897/mycokeys.55.3501

Feasibility of a walking virtual reality system for rehabilitation: objective and subjective parameters

[EN] Background: Even though virtual reality (VR) is increasingly used in rehabilitation, the implementation of walking navigation in VR still poses a technological challenge for current motion tracking systems. Different metaphors simulate locomotion without involving real gait kinematics, which can affect presence, orientation, spatial memory and cognition, and even performance. All these factors can dissuade their use in rehabilitation. We hypothesize that a marker-based head tracking solution would allow walking in VR with high sense of presence and without causing sickness. The objectives of this study were to determine the accuracy, the jitter, and the lag of the tracking system and its elicited sickness and presence in comparison of a CAVE system. Methods: The accuracy and the jitter around the working area at three different heights and the lag of the head tracking system were analyzed. In addition, 47 healthy subjects completed a search task that involved navigation in the walking VR system and in the CAVE system. Navigation was enabled by natural locomotion in the walking VR system and through a specific device in the CAVE system. An HMD was used as display in the walking VR system. After interacting with each system, subjects rated their sickness in a seven-point scale and their presence in the Slater-Usoh-Steed Questionnaire and a modified version of the Presence Questionnaire. Results: Better performance was registered at higher heights, where accuracy was less than 0.6 cm and the jitter was about 6 mm. The lag of the system was 120 ms. Participants reported that both systems caused similar low levels of sickness (about 2.4 over 7). However, ratings showed that the walking VR system elicited higher sense of presence than the CAVE system in both the Slater-Usoh-Steed Questionnaire (17.6 +/- 0.3 vs 14.6 +/- 0.6 over 21, respectively) and the modified Presence Questionnaire (107.4 +/- 2.0 vs 93.5 +/- 3.2 over 147, respectively). Conclusions: The marker-based solution provided accurate, robust, and fast head tracking to allow navigation in the VR system by walking without causing relevant sickness and promoting higher sense of presence than CAVE systems, thus enabling natural walking in full-scale environments, which can enhance the ecological validity of VR-based rehabilitation applications.The authors wish to thank the staff of LabHuman for their support in this project, especially José Miguel Martínez and José Roda for their assistance. This study was funded in part by Ministerio de Economia y Competitividad of Spain (Project NeuroVR, TIN2013-44741-R and Project REACT, TIN2014-61975-EXP), by Ministerio de Educacion y Ciencia of Spain (Project Consolider-C, SEJ2006-14301/PSIC), and by Universitat Politecnica de Valencia (Grant PAID-10-14).Borrego, A.; Latorre Grau, J.; Llorens Rodríguez, R.; Alcañiz Raya, ML.; Noé, E. (2016). Feasibility of a walking virtual reality system for rehabilitation: objective and subjective parameters. Journal of NeuroEngineering and Rehabilitation. 13:1-9. https://doi.org/10.1186/s12984-016-0174-1S1913Lee KM. Presence. Explicated Communication Theory. 2004;14(1):27–50.Riva G. Is presence a technology issue? Some insights from cognitive sciences. Virtual Reality. 2009;13(3):159–69.Banos RM, et al. Immersion and emotion: their impact on the sense of presence. Cyberpsychol Behav. 2004;7(6):734–41.Llorens R, et al. Tracking systems for virtual rehabilitation: objective performance vs. subjective experience. A practical scenario. Sensors (Basel). 2015;15(3):6586–606.Navarro MD, et al. Validation of a low-cost virtual reality system for training street-crossing. A comparative study in healthy, neglected and non-neglected stroke individuals. Neuropsychol Rehabil. 2013;23(4):597–618.Parsons TD. Virtual reality for enhanced ecological validity and experimental control in the clinical, affective and social neurosciences. Front Hum Neurosci. 2015;9:660.Cameirao MS, et al. Neurorehabilitation using the virtual reality based Rehabilitation Gaming System: methodology, design, psychometrics, usability and validation. J Neuroeng Rehabil. 2010;7:48.Llorens R, et al. Improvement in balance using a virtual reality-based stepping exercise: a randomized controlled trial involving individuals with chronic stroke. Clin Rehabil. 2015;29(3):261–8.Llorens R, et al. Videogame-based group therapy to improve self-awareness and social skills after traumatic brain injury. J Neuroeng Rehabil. 2015;12:37.Fong KN, et al. Usability of a virtual reality environment simulating an automated teller machine for assessing and training persons with acquired brain injury. J Neuroeng Rehabil. 2010;7:19.Levin MF, Weiss PL, Keshner EA. Emergence of virtual reality as a tool for upper limb rehabilitation: incorporation of motor control and motor learning principles. Phys Ther. 2015;95(3):415–25.Llorens R, et al. Effectiveness, usability, and cost-benefit of a virtual reality-based telerehabilitation program for balance recovery after stroke: a randomized controlled trial. Arch Phys Med Rehabil. 2015;96(3):418–25. e2.Cruz-Neira C, et al. Scientists in wonderland: A report on visualization applications in the CAVE virtual reality environment. In: 1993. Proceedings IEEE 1993 Symposium on Research Frontiers in Virtual Reality. 1993.Juan MC, Perez D. Comparison of the levels of presence and anxiety in an acrophobic environment viewed via HMD or CAVE. Presence. 2009;18(3):232–48.Yang YR, et al. Virtual reality-based training improves community ambulation in individuals with stroke: a randomized controlled trial. Gait Posture. 2008;28(2):201–6.Cho KH, Lee WH. Virtual walking training program using a real-world video recording for patients with chronic stroke: a pilot study. Am J Phys Med Rehabil. 2013;92(5):371–84.Darter BJ, Wilken JM. Gait training with virtual reality-based real-time feedback: improving gait performance following transfemoral amputation. Phys Ther. 2011;91(9):1385–94.Yang S, et al. Improving balance skills in patients who had stroke through virtual reality treadmill training. Am J Phys Med Rehabil. 2011;90(12):969–78.Walker ML, et al. Virtual reality-enhanced partial body weight-supported treadmill training poststroke: feasibility and effectiveness in 6 subjects. Arch Phys Med Rehabil. 2010;91(1):115–22.Riley PO, et al. A kinematic and kinetic comparison of overground and treadmill walking in healthy subjects. Gait Posture. 2007;26(1):17–24.Alton F, et al. A kinematic comparison of overground and treadmill walking. Clin Biomech. 1998;13(6):434–40.Lee SJ, Hidler J. Biomechanics of overground vs. treadmill walking in healthy individuals. J Appl Physiol. 2008;104(3).Slater M. Measuring presence: a response to the witmer and Singer presence questionnaire. Presence. 1999;8(5):560–5.Viau A, et al. Reaching in reality and virtual reality: a comparison of movement kinematics in healthy subjects and in adults with hemiparesis. J Neuroeng Rehabil. 2004;1(1):11.Parsons TD, et al. The potential of function-led virtual environments for ecologically valid measures of executive function in experimental and clinical neuropsychology. Neuropsychol Rehabil. 2015;11:1–31. doi: 10.1080/09602011.2015.1109524 .Aravind G, Lamontagne A. Perceptual and locomotor factors affect obstacle avoidance in persons with visuospatial neglect. J Neuroeng Rehabil. 2014;11:38.Darekar A, Lamontagne A, Fung J. Dynamic clearance measure to evaluate locomotor and perceptuo-motor strategies used for obstacle circumvention in a virtual environment. Hum Mov Sci. 2015;40:359–71.Whittle MW. Chapter 4 - Methods of gait analysis. In: Whittle MW, editor. Gait analysis. Edinburgh: Butterworth-Heinemann; 2007. p. 137–75.Hodgson E, et al. WeaVR: a self-contained and wearable immersive virtual environment simulation system. Behav Res Methods. 2015;47(1):296–307.Akizuki H, et al. Effects of immersion in virtual reality on postural control. Neurosci Lett. 2005;379(1):23–6.Thies SB, et al. Comparison of linear accelerations from three measurement systems during "reach & grasp". Med Eng Phys. 2007;29(9):967–72.Fiala M. Designing highly reliable fiducial markers. IEEE Trans Pattern Anal Mach Intell. 2010;32(7):1317–24.Garrido-Jurado S, et al. 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In: Third IEEE and ACM International symposium on mixed and augmented reality, ISMAR 2004. 2004.Malbezin P, Piekarski W, Thomas BH. Measuring ARTootKit accuracy in long distance tracking experiments. In: The first IEEE International workshop augmented reality toolkit. 2002.Paquette C, Paquet N, Fung J. Aging affects coordination of rapid head motions with trunk and pelvis movements during standing and walking. Gait Posture. 2006;24(1):62–9.Graham JE, et al. Walking speed threshold for classifying walking independence in hospitalized older adults. Phys Ther. 2010;90(11):1591–7.Gorea A. A refresher of the original Bloch’s Law paper (bloch, july 1885). i-Perception. 2015;6:4.Moss JD, Muth ER. Characteristics of head-mounted displays and their effects on Simulator sickness. Hum Factors. 2011;53(3):308–19.Draper MH, et al. Effects of image scale and system time delay on Simulator sickness within head-coupled virtual environments. Hum Factors. 2001;43(1):129–46.Fujisaki W. 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Global overview of the management of acute cholecystitis during the COVID-19 pandemic (CHOLECOVID study)

Background: This study provides a global overview of the management of patients with acute cholecystitis during the initial phase of the COVID-19 pandemic. Methods: CHOLECOVID is an international, multicentre, observational comparative study of patients admitted to hospital with acute cholecystitis during the COVID-19 pandemic. Data on management were collected for a 2-month study interval coincident with the WHO declaration of the SARS-CoV-2 pandemic and compared with an equivalent pre-pandemic time interval. Mediation analysis examined the influence of SARS-COV-2 infection on 30-day mortality. Results: This study collected data on 9783 patients with acute cholecystitis admitted to 247 hospitals across the world. The pandemic was associated with reduced availability of surgical workforce and operating facilities globally, a significant shift to worse severity of disease, and increased use of conservative management. There was a reduction (both absolute and proportionate) in the number of patients undergoing cholecystectomy from 3095 patients (56.2 per cent) pre-pandemic to 1998 patients (46.2 per cent) during the pandemic but there was no difference in 30-day all-cause mortality after cholecystectomy comparing the pre-pandemic interval with the pandemic (13 patients (0.4 per cent) pre-pandemic to 13 patients (0.6 per cent) pandemic; P = 0.355). In mediation analysis, an admission with acute cholecystitis during the pandemic was associated with a non-significant increased risk of death (OR 1.29, 95 per cent c.i. 0.93 to 1.79, P = 0.121). Conclusion: CHOLECOVID provides a unique overview of the treatment of patients with cholecystitis across the globe during the first months of the SARS-CoV-2 pandemic. The study highlights the need for system resilience in retention of elective surgical activity. Cholecystectomy was associated with a low risk of mortality and deferral of treatment results in an increase in avoidable morbidity that represents the non-COVID cost of this pandemic