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Carl Schorlemmer (1834-1892), the first professor of organic chemistry in the Owens College, Manchester (and in England), was the prominent Anglo-German chemist and historian of chemistry of the second half of the 19th century. He studied the constitution of paraffinic hydrocarbons. The purpose of this paper is to familiarize readers with the important events in the life of Schorlemmer and his research activities and writing, in particular some of his experimental results, as well as his selected publications. [ABSTRACT FROM AUTHOR]

Frederick Soddy (1877-1956) was the most prominent chemists of the first half of the 20th century. He is known for his numerous papers in the field of radiochemistry. He was the laureate of the Nobel Prize in Chemistry for 1921. The purpose of this paper is to familiarize readers with the important events in the life of Soddy and his research activities, in particular with selected results of his experimental studies as well as with his selected publications. In addition, his writing activity was described, in particular his books, well known in various countries, were presented. [ABSTRACT FROM AUTHOR]

Jean Antoine Chaptal (1756-1832) was one of the important chemists of the second half of the 18th century and the first half of 19th century. He wrote a number of works dealing with various branches of applied chemistry. The purpose of this paper is to familiarize readers with the important events in the life of Chaptal and his writing activities, in particular with his chemistry textbooks and books on applied chemistry, well-known in different countries. In addition, his research activities is briefly described. [ABSTRACT FROM AUTHOR]

Sophus Mads Jørgensen (1837-1914) was one of the important chemists of the second half of the XIX century and the first decade of the XX century. He was one of the founders of the chemistry of complex compounds. He also made major contributions to the chemistry of platinum, cobalt, chromium and rhodium compounds. The purpose of this paper is to familiarize readers with the important events in the life of Jørgensen and his writing activities, in particular with his chemistry books. In addition, his research activities are briefly described. [ABSTRACT FROM AUTHOR]

Richard Anschütz (1852-1937) was an important German chemist in the second half of the XIX century and the first quarter of the XX century. He carried out experimental studies in the field of organic chemistry. He proposed a new method for the synthesis of anthracene. He developed vacuum distillation. He prepared pure chloroform. He rescued the names of Archibald Scott Couper (1831-1892) and Joseph Loschmidt (1821-1895) from oblivion. The purpose of this paper is to familiarize readers with the important events in the life of Anschütz. In addition, literature on his selected articles and books is presented. [ABSTRACT FROM AUTHOR]

Edgar Fahs Smith (1854-1928) was one of the great American chemists. He has done a lot of experimental studies. He carried out researches in the fields of organic, inorganic, and analytical chemistry, elektrochemistry and mineralogy. He developed the rotating anode. He wrote many works in the field of history of American chemistry. The purpose of this paper is to familiarize readers with the important events in the life of Smith. In addition, his participation in the preparation of the first visit of Marie Curie (1867-1934) to the USA in 1921 is described and literature on his selected articles and books is presented. [ABSTRACT FROM AUTHOR]

Ira Remsen (1846-1927) was one of the great American chemists. He carried out his experimental studies in the field of organic chemistry. In 1879, he became a co-discoverer of saccharin. He was the first professor of chemistry (1876-1901) and the second president (1901-1913) of the Johns Hopkins University in Baltimore. The purpose of this paper is to familiarize readers with the important events in the life of Remsen and his writing activities, in particular with his chemistry textbooks, well-known in various countries. In addition, literature on his selected articles is presented. [ABSTRACT FROM AUTHOR]

Paul-Émile (François) Lecoq de Boisbaudran (1838-1912) was an important French chemist in the second half of the XIX century and the first decade of the XX century. He was one of the founders of spectroscopy. He discovered gallium (1875), samarium (1879), and dysprosium (1886) and improved methods for the separation of rare earths elements. The purpose of this paper is to familiarize readers with the important events in the life of Lecoq de Boisbaudran and his great discoveries. In addition, literature on his selected papers and books, as well as literature on his chapters in books is presented. [ABSTRACT FROM AUTHOR]

Clemens Alexander Winkler (1838-1904) was one of the prominent chemists of the second half of the XIX century. He was the founder of technical gas-analysis. He made major contributions both to pure and applied chemistry. He also developed a contact method for the production of sulfuric anhydride (sulfur trioxide) and discovered Germanium. The purpose of this paper is to familiarize readers with the important events in the life of Winkler and his research activities, in particular with his selected publications as well as with his writing activities, in particular with his books. In addition, literature on his correspondence with some great chemists is given. [ABSTRACT FROM AUTHOR]

Ernst Julius Cohen (1869-1944) was an outstanding Dutch chemist and historian of chemistry of the second half of the XIX century and the first half of the XX century. He contributed to the fields of polymorphism, thermochemistry, electrochemistry and piezochemistry. He also studied physical isomerism. His experimental studies on allotropy has been published in a large number of publication. The purpose of this paper is to familiarize readers with the important events in the life of Cohen and his research activities, in particular with his selected publications as well as with his writing activities, in particular with his books. [ABSTRACT FROM AUTHOR]

Sir Thomas Edward Thorpe (1845-1925) was one of the most prominent chemists of the second half of the 19th century. He studied phosphorus oxides and fluorine compounds. He is known for his works on the determination of the atomic weights of chemical elements and for his books on chemistry and the history of chemistry. The purpose of this paper is to familiarize readers with the important events in the life of Thorpe and his writing and research activities, in particular some of his experimental results, as well as his selected publications. [ABSTRACT FROM AUTHOR]

Adolf von Baeyer (1835-1917) was the most prominent chemists of the second half of the 19th century and the early part of the twentieth century. He is known for his many works in the field of organic chemistry. He was the first to synthesize indigo. He was awarded the Nobel Prize in Chemistry in 1905. The purpose of this paper is to familiarize readers with the important events in the life of Baeyer and his research activities, in particular with selected results of his experimental studies as well as with his selected publications. In addition, literature on his correspondence is given. [ABSTRACT FROM AUTHOR]

Victor Meyer (1848-1897) was one of the most outstanding chemist of the second half of the 19th century. He is known for his numerous papers in the field of organic chemistry. The purpose of this paper is to familiarize readers with the important events in the life of Meyer. In addition, his research activities is briefly described, and especially the chemical reaction named after him. [ABSTRACT FROM AUTHOR]

Hans Landolt (1831-1910) was one of the important chemists of the second half of the XIX century and the first decade of the XX century. The purpose of this paper is to familiarize readers with the important events in the life of Landolt and his writing activities, in particular with his chemistry books. In addition, his research activities is briefly described, and especially the chemical reaction named after him. [ABSTRACT FROM AUTHOR]

Thomas Edward Thorpe (1845-1925) was one of the most prominent chemists of the second half of the 19th century. He studied phosphorus oxides and fluorine compounds. He is known for his works on the determination of the atomic weights of chemical elements and for his books on chemistry and the history of chemistry. The purpose of this paper is to familiarize readers with the important events in the life of Thorpe and his writing and research activities, in particular some of his experimental results, as well as his selected publications. [ABSTRACT FROM AUTHOR]

Johan Gadolin (1760-1852), considered the father of Finnish chemistry, was one of the leading chemists of the second half of the 18th century and the first half of the 19th century. His life and scientific achievements were described in the literature published between the 19th and 21st centuries. The purpose of this paper is to familiarize readers with the important events in the life of Gadolin and his research activities, in particular some of his research results, as well as his selected publications. In addition, the names of authors of biographical notes or biographies about Gadolin, published in 1839-2017 are presented. [ABSTRACT FROM AUTHOR]

Victor von Richter (1841-1891) was one of the important chemists of the second half of the 19th century. The purpose of this paper is to familiarize readers with the important events in the life of Richter and his writing activities, in particular with his chemistry textbooks for higher education, well-known in different countries. In addition, his research activities is briefly described, and especially the chemical reactions named after him. [ABSTRACT FROM AUTHOR]

The purpose of this article was to familiarize readers with burning lenses, which were used by 18th century by some English and French chemists as a means of reaching high temperatures. However, not all experiments have given satisfactory results. The failures in the melting platinum using various burning lenses led Lavoisier to develop a new method of melting platinum using oxygen. In addition, in this article a literature was reviewed, including books on chemistry and the history of chemistry published in various countries to discuss the problem of oxygen discovery by Joseph Priestley (1733-1804), Carl Wilhelm Scheele (1742-1786) and Antoine Laurent Lavoisier (1743-1794). [ABSTRACT FROM AUTHOR]

It is a survey of literature concerning both life and scientific activity of Nikolai Nikolaevich Zinin. Special attention is paid to his epoch-making discovery made by him in 1842 and his chemical works published in 1839-1880. This survey is supplemented with: 1) names of the authors of Zinin's biographies, biographical notes, and references to him, 2) information about Zinin's works bibliography, 3) description of the selected facts of his life. [ABSTRACT FROM AUTHOR]

In this article, the author reviews literature concerning the great Mendeleev's achievements in the seventies of the XIX century, i.e. discovery of the periodic law and fulfillment of his early predictions of unknown elements. Special attention was paid to the references concerning these achievements by chemists - authors of the English, German, and French chemical books in 1871 - 1917. This review was enriched with: 1) selected facts from Mendeleev's life and scientific activity; 2) Mendeleev's stay abroad and participation in some celebrities, and 3) a list of the authors of his biography in Russia and other countries in the world. [ABSTRACT FROM AUTHOR]

In this article, a literature concerning A.P. Borodin's life and his activity as the chemist and composer has been reviewed. Special attention has been paid to the references to his life and achievements in chemistry in 1881 - 2012 as well as his chemical work published between 1858 and 1886. Literature review was supplemented with: 1) description of the selected facts from Borodin's life; 2) acquaintance of the readers with the selected authors of his biography, and 3) description of the Borodin's premature death causes. [ABSTRACT FROM AUTHOR]

In this article the literature on Carl Wilhelm Scheele (1742-1786) is reviewed, including books on chemistry and the history of chemistry, published between the 18th and the 21st century in different countries in order to: 1) familiarize readers with the names of authors of biographies and biographical notes about Carl Wilhelm Scheele, published in books in 1833-2017, 2) discusse the priority problem for the discovery of oxygen by Joseph Priestley (1733-1804) and Scheele, 3) familiarize readers with literature sources regarding Scheele's letter to Antoine Laurent Lavoisier (1743-1794), written on September 30, 1774, 4) show the causes of Scheele's premature death, 5) familiarize readers with opinions about Scheele expressed by chemists in 1819-1942. To convey the atmosphere in which the authors of books in various countries created them, as well as to express their feelings about Scheele, and in order to avoid unintentional transformations of their thoughts, in this article, authors words are quoted in literal wording. Their reading may be helpful in the education of the students of chemistry, because looking at certain issues through the prism of the history of science will certainly facilitate the acquisition and understanding the knowledge by them. This article will be a source of reflection regarding the history of chemistry, in which Scheele, Priestley and Lavoisier were active. [ABSTRACT FROM AUTHOR]

Although radioactive iodine imaging and therapy are one of the earliest applications of theranostics, there still remain a number of unresolved clinical questions as to the optimization of diagnostic techniques and dosimetry protocols. I-124 as a positron emission tomography (PET) radiotracer has the potential to improve the current clinical practice in the diagnosis and treatment of differentiated thyroid cancer. The higher sensitivity and spatial resolution of PET/computed tomography (CT) compared to standard gamma scintigraphy can aid in the detection of recurrent or metastatic disease and provide more accurate measurements of metabolic tumor volumes. However the complex decay schema of I-124 poses challenges to quantitative PET imaging. More prospective studies are needed to define optimal dosimetry protocols and to improve patientspecific treatment planning strategies, taking into account not only the absorbed dose to tumors but also methods to avoid toxicity to normal organs. A historical perspective of I-124 imaging and dosimetry as well as future concepts are discussed. [ABSTRACT FROM AUTHOR]

Neutron generators based on inertial electrostatic confinement fusion were considered for the design of a neutron irradiation facility for explanted organ Boron Neutron Capture Therapy (BNCT) that could be installed in a health care center as well as in research areas. The chosen facility configuration is “irradiation chamber”, a ~20×20×40 cm 3 cavity near or in the center of the facility geometry where samples to be irradiated can be placed. Neutron flux calculations were performed to study different manners for improving scattering processes and, consequently, optimize neutron flux in the irradiation position. Flux distributions were assessed through numerical simulations of several models implemented in MCNP5 particle transport code. Simulation results provided a wide spectrum of combinations of net fluxes and energy spectrum distributions. Among them one can find a group that can provide thermal neutron fluxes per unit of production rate in a range from 4.1·10 −4 cm −2 to 1.6·10 −3 cm −2 with epithermal-to-thermal ratios between 0.3% and 13% and fast-to-thermal ratios between 0.01% to 8%. Neutron generators could be built to provide more than 10 10 n s −1 and, consequently, with an arrangement of several generators appropriate enough neutron fluxes could be obtained that would be useful for several BNCT-related irradiations and, eventually, for clinical practice. [ABSTRACT FROM AUTHOR]

Neutron transport calculation is a key factor in BNCT numerical dosimetry assessments where thermal neutron flux is intimately related to the neutron dose, specially, the therapeutic boron dose. In this work, numerical calculations in phantoms were performed to determine the importance of utilizing the appropriate thermal scattering treatment for different organic tissues. Two thermal treatments for the neutron scattering were included in the simulations: hydrogen bounded in bulk water and hydrogen bounded in a lipid like carbon chain (polyethylene). The results showed difference between both thermal treatments that can reach several percent points depending on the type of source and irradiated geometry. [ABSTRACT FROM AUTHOR]

Neutron transport calculation is a key factor in BNCT numerical dosimetry assessments where thermal neutron flux is intimately related to the neutron dose, specially, the therapeutic boron dose. In this work, numerical calculations in phantoms were performed to determine the importance of utilizing the appropriate thermal scattering treatment for different organic tissues. Two thermal treatments for the neutron scattering were included in the simulations: hydrogen bounded in bulk water and hydrogen bounded in a lipid like carbon chain (polyethylene). The results showed difference between both thermal treatments that can reach several percent points depending on the type of source and irradiated geometry. [ABSTRACT FROM AUTHOR]

Abstract: A PGNAA facility is being developed for 10B concentration measurements at RA-3 reactor. Its design targets detection limits better than tenths of a microgram and irradiation times on the order of minutes. Computational models were developed, which estimated thermal neutron fluxes in irradiation position to be larger than 109 ncm−2 s−1. Calculated amounts of photons and fast neutrons make necessary for filter/moderator arrangements. An irradiation device was designed and numerically tested, which is being built and is to be used for performing characterizing measurements. [Copyright &y& Elsevier]

Purpose: A rhodium self-powered neutron detector (Rh SPND) has been specifically developed by the Comisión Nacional de Energía Atómica (CNEA) of Argentina to measure locally and in real time thermal neutron fluxes in patients treated with boron neutron capture therapy (BNCT). In this work, the thermal and epithermal neutron response of the Rh SPND was evaluated by studying the detector response to two different reactor spectra. In addition, during clinical trials of the BNCT Project of the CNEA, on-line neutron flux measurements using the specially designed detector were assessed. Methods: The first calibration of the detector was done with the well-thermalized neutron spectrum of the CNEA RA-3 reactor thermal column. For this purpose, the reactor spectrum was approximated by a Maxwell-Boltzmann distribution in the thermal energy range. The second calibration was done at different positions along the central axis of a water-filled cylindrical phantom, placed in the mixed thermal-epithermal neutron beam of CNEA RA-6 reactor. In this latter case, the RA-6 neutron spectrum had been well characterized by both calculation and measurement, and it presented some marked differences with the ideal spectrum considered for SPND calibrations at RA-3. In addition, the RA-6 neutron spectrum varied with depth in the water phantom and thus the percentage of the epithermal contribution to the total neutron flux changed at each measurement location. Local (one point-position) and global (several points-positions) and thermal and mixed-field thermal neutron sensitivities were determined from these measurements. Thermal neutron flux was also measured during BNCT clinical trials within the irradiation fields incident on the patients. In order to achieve this, the detector was placed on patient's skin at dosimetric reference points for each one of the fields. System stability was adequate for this kind of measurement. Results: Local mixed-field thermal neutron sensitivities and global thermal and mixed-field thermal neutron sensitivities derived from measurements performed at the RA-6 were compared and no significant differences were found. Global RA-6-based thermal neutron sensitivity showed agreement with pure thermal neutron sensitivity measurements performed in the RA-3 spectrum. Additionally, the detector response proved nearly unchanged by differences in neutron spectra from real (RA-6 BNCT beam) and ideal (considered for calibration calculations at RA-3) neutron source descriptions. The results confirm that the special design of the Rh SPND can be considered as having a pure thermal response for neutron spectra with epithermal-to-thermal flux ratios up to 12%. In addition, the linear response of the detector to thermal flux allows the use of a mixed-field thermal neutron sensitivity of 1.95 ± 0.05 × 10-21 A n-1·cm2·s. This sensitivity can be used in spectra with up to 21% epithermal-to-thermal flux ratio without significant error due to epithermal neutron and gamma induced effects. The values of the measured fluxes in clinical applications had discrepancies with calculated results that were in the range of -25% to +30%, which shows the importance of a local on-line independent measurement as part of a treatment planning quality control system. Conclusions: The usefulness of the CNEA Rh SPND for the on-line local measurement of thermal neutron flux on BNCT patients has been demonstrated based on an appropriate neutron spectra calibration and clinical applications. [ABSTRACT FROM AUTHOR]

Abstract: The potential of the biological control fungus Penicillium oxalicum to suppress wilt caused by Fusarium oxysporum f. sp. melonis and F. oxysporum f. sp. niveum on melon and watermelon, respectively, was tested under different growth conditions. The area under disease progress curve of F. oxysporum f. sp. melonis infected melon plants was significantly reduced in growth chamber and field experiments. In glasshouse experiments, it was necessary to apply P. oxalicum and dazomet in order to reduce Fusarium wilt severity in melons caused by F. oxysporum f. sp. melonis. For watermelons, we found that P. oxalicum alone reduced the area under the disease progress curve by 58% in the growth chamber experiments and 54% in the glasshouse experiments. From these results, we suggested that P. oxalicum may be effective for the management of Fusarium wilt in melon and watermelon plants. [Copyright &y& Elsevier]

Conditions affecting germination and growth of Fusarium mangiferae, causal agent of mango malformation disease, were studied in vitro. Both conidial germination and colony growth required temperatures >5°C and reached a peak at 28 and 25°C, respectively. A minimum 2-h wetness period was required for conidial germination, reaching a peak after 8 h of wetness. High incidence of fungal colonization in buds, predominantly the apical buds, was detected compared with inoculated leaves. The pathogen was detected in the roots of inoculated soil 19 weeks postinoculation but not in aboveground parts of the plants, and symptoms of the disease were not observed, either. Dry, malformed inflorescence debris serving as a source of inoculum caused significantly higher colonization (52 and 20%) of inoculated buds, compared with that (0%) of the untreated controls. Incidence of sampled leaf disks bearing propagules of E mangiferae from an infected orchard peaked in June and July and decreased during the following months, whereas airborne infections on 1-month-old branches was the highest in May and June, corresponding with inoculum availability released from infected inflorescences. Colonization pattern, determined in naturally infected vegetative and woody branches, was significantly higher in node sections than in the internode sections. This study sheds light on infection dynamics, colonization patters, and the disease cycle of F. mangiferae in mango. [ABSTRACT FROM AUTHOR]

Abstract: We studied (a) the extent adhesion of Penicillium oxalicum conidia to tomato roots after application of P. oxalicum conidial formulations with or without stickers, (b) the relationship between the extent of conidial adhesion to roots and biocontrol of the conidial formulations against tomato wilt, and (c) colonisation of roots by P. oxalicum. Adhesion of P. oxalicum conidia to tomato roots occurred within the first minute of contact between the root and the conidial formulation and the bonding strength was sufficiently strong to prevent conidial removal from the roots. In addition, some formulations with stickers that increased conidial adhesion to roots improved the biocontrol of tomato wilt, when compared to that of formulations without stickers. A “dried conidia without stickers” with 0.025% Nu-Film 17 had no effect on the biocontrol of tomato wilt, despite good adherence of the conidia to the roots. The numbers of P. oxalicum conidia that adhered to the roots was constant for 60 days after application of a “dried conidia without stickers” conidial formulation. The significance of these results (speed of adhesion, number of adhered conidia, and variability of conidial external surface) are discussed in relation to the biocontrol success of tomato wilt using different types of conidial formulations with and without stickers. [Copyright &y& Elsevier]

Inoculum availability and conidial dispersal patterns of Fusarium mangiferae, causal agent of mango malformation disease, were studied during 2006 and 2007 in an experimental orchard. The spatial pattern of primary infections in a heavily infected commercial mango orchard corresponded with a typical dispersal pattern caused by airborne propagules. Malformed inflorescences were first observed in mid-March, gradually increased, reaching a peak in May, and declined to negligible levels in August. The sporulation capacity of the malformed inflorescences was evaluated during three consecutive months. Significantly higher numbers of conidia per gram of malformed inflorescence were detected in May and June than in April. Annual conidial dissemination patterns were evaluated by active and passive trapping of conidia. A peak in trapped airborne conidia was detected in May and June for both years. The daily pattern of conidial dispersal was not associated with a specifically discernable time of day, and an exponential correlation was determined between mean relative humidity (RH) and mean number of trapped conidia. Higher numbers of conidia were trapped when RH values were low (<55%). This is the first detailed report on airborne dispersal of F. mangiferae, serving as the primary means of inoculum spread. [ABSTRACT FROM AUTHOR]

An isolate of Ampelomyces quisqualis obtained from a Oidium sp. infecting Catha edulis in Israel, proved to be infective to several powdery mildew fungi belonging to the genera Oidium, Erysiphe, Sphaerotheca, Podosphaera, Uncinula, and Leveillula. In field trials, A. quisqualis parasitized the powdery mildews of cucumber, carrot and mango and reduced the disease. Hyperparasitism on Oidium mangiferae is reported for the first time. A. quisqualis was tolerant to many fungicides currently used to control powdery mildews and/or other plant diseases. In one experiment, treating powdery mildew of cucumber (cv. Hazera 205) with spores of A. quisqualis alone, significantly decreased disease severity and increased cucumber yields by approximately 50%. However, a greater increase in yield was obtained by using the fungicide pyrazophos alone or in combination with the hyperparasite. In a second experiment, using cv. Dalila, all treatments increased the yield over the untreated control which did not produce fruits. [ABSTRACT FROM AUTHOR]

The purpose of this study was to re-validate a former study about the importance and validity of FEASP-emotions and related measurements. Data were collected from 654 Polish high school students and 147 teachers of 14 secondary schools. Results showed that emotions and especially FEASP-emotions (fear, envy, anger, sympathy, and pleasure) were important in daily instruction and that they were measured with high reliability. Gender differences also illustrated some predictive validity. [ABSTRACT FROM AUTHOR]

The purpose of this study was to re-validate a former study about the importance and validity of FEASP-emotions and related measurements. Data were collected from 654 Polish high school students and 147 teachers of 14 secondary schools. Results showed that emotions and especially FEASP-emotions (fear, envy, anger, sympathy, and pleasure) were important in daily instruction and that they were measured with high reliability. Gender differences also illustrated some predictive validity. [ABSTRACT FROM AUTHOR]

A prompt gamma neutron activation analysis (PGNAA) facility is being designed and developed at the channel 4 of the RA-3 nuclear reactor, placed at the Ezeiza Atomic Center of the National Atomic Energy Commission of Argentina. The main purpose of such facility is to perform fast measurements of 10 B concentration in biological samples, in the context of Boron Neutron Capture Therapy (BNCT). At this stage, a simulation guided design process has been performed for this facility. The MCNP6 code was used to perform computational simulations which have received the feedback from measurements of the implemented designs through an iterative process. The specifications of the required beam have been defined based on the sizes and types of biological samples and the lowest values of boron concentrations that would need to be measured for BNCT activities. The conformation of the neutron beam in terms of geometry and energy, has been achieved by the implementation of a system of collimators and filters. The goal of this development is to be able to measure micrograms of 10 B in a few minutes of irradiation. This measurement technique needs no preparation of the samples, is reliable, robust and safe. In order to satisfy these requirements, it is necessary to provide a high thermal neutron flux E < 0. 4 eV , ϕ th with low epithermal 0. 4 eV < E < 10 keV , ϕ epi and fast E > 10 keV , ϕ f components of the neutron flux, and also low gamma flux in the sample position and its surroundings. Based on the results of the simulations of the designs, the one that was considered the best design at this stage resulted in a ϕ th = (5. 6 ± 1. 4) × 1 0 7 n cm − 2 s − 1 with around four orders of magnitude less for higher energy components at sample position. The diameter of the beam with uniform ϕ th at the sample position was 3. 50 ± 0. 25 cm. The next design stage will include coupled transport of neutron and gamma particles. It will be focused in optimizing the gamma background at the detector position, which would allow to have a functional configuration of the complete measuring device. • A development of a prompt gamma facility for boron determination is on course. • Boron Neutron Capture Therapy applications are the main purpose of this facility. • The facility is located at channel 4 of the RA-3 nuclear reactor in Argentina. • Simulations with Monte Carlo particle transport guided the design process. • High neutron flux with low high energy components resulted at sample position. [ABSTRACT FROM AUTHOR]

Radiation dose calculation engine as a base for X-ray radiation treatment planning has been developed using Geant4 Monte Carlo toolkit and applying highly efficient voxel geometry with flexible material definition. With this engine we can easily customize flexible patient and beam modules, thus obtaining a common backend applicable to various radiation therapy planning systems. The engine was tested using the available experimental data for a water phantom and using the real CT data in X-ray therapies; the calculated doses were compared also against the MCNP5/X values. The results show that this Geant4 based radiation dose calculation engine has much higher computational speed than the models generated by an MCNP5/X-based treatment planning tool without any loss of accuracy. In addition, Geant4 is an open source code and applies no restrictions to the users. [ABSTRACT FROM AUTHOR]

The role of the mango bud mite, Acerica mangiferae, in carrying conidia of Fusarium mangiferae, vectoring them into potential infection sites, and assisting fungal infection and dissemination was studied. Following the mite's exposure to a green fluorescent protein-marked isolate, conidia were observed clinging to the mite's body. Agar plugs bearing either bud mites or the pathogen were placed on leaves near the apical buds of potted mango plants. Conidia were found in bud bracts only when both mites and conidia were co-inoculated on the plant, demonstrating that the mite vectored the conidia into the apical bud. Potted mango plants were inoculated with conidia in the presence or absence of mites. Frequency and severity of infected buds were significantly higher in the presence of mites, revealing their signilicant role in the fungal infection process. Conidia and mite presence were monitored with traps in a diseased orchard over a 2-year period. No windborne bud mites bearing conidia were found; however, high numbers of borne conidia were detected in the traps. These results suggest that A. mangiferae can carry and vector conidia between buds and assist in fungal penetration but does not play a role in the aerial dissemination of conidia between trees. [ABSTRACT FROM AUTHOR]

Abstract: Biological control of powdery mildew on strawberry leaves by Penicillium oxalicum applications was achieved on different cultivars and lines in growth chambers and in open-field nurseries. Growth chamber conditions were more conducive to the development of natural infection of powdery mildew on the various cultivars and lines than plants cultivated in open-field nurseries. Penicillium oxalicum-treated strawberry cultivars and lines showed a significant reduction in the amount of powdery mildew in growth chamber (except for Ventana) and open-field nursery experiments. These results indicate that P. oxalicum may be an effective treatment for biological control of strawberry powdery mildew in open-field nurseries of strawberries. [Copyright &y& Elsevier]

A novel system to determine thermal neutron flux in real time during NCT treatments was developed in the National Atomic Energy Commission of Argentina. The system is based on a special self-powered detector that can be implanted in patients owing to its small size and biocompatibility. High voltage is not required to operate this kind of detectors, which is a considerable advantage in terms of medical uses.By choosing the appropriate materials, it was possible to obtain a prototype with thermal neutron sensitivity providing for an adequate signal level in typical NCT thermal fluxes. It was also possible to minimize gamma response in order to neglect its contribution. [Copyright &y& Elsevier]

Apricot gummosis pathogens - the fungi Hendersonula toruloidea, a Cytosporina sp. and a Cytospora sp., produce cellulase (endo-l,4-β-glucanase, carboxymethylcellulase, CMCase) in culture. Cytospora sp. produced significantly lower amounts of cellulase than H. toruloidea and Cytosporina sp. The tendency of cellulase accumulation inside apricot stems infected with either H. toruloidea or Cytosporina sp. is similar: most of the cellulase was found in the necrotic area, whereas comparatively small amounts accumulated at the advancing edge of the disease symptom. H. toruloidea produces cellulase with a molecular mass of 76 kDa. [ABSTRACT FROM AUTHOR]

In the frame of the Argentine BNCT Project a new research line has been started to study the application of BNCT to the treatment of locoregional recurrences of HER2+ breast cancer subtype. Based on former studies, the strategy considers the use of immunoliposomes as boron carriers nanovehicles to target HER2 overexpressing cells. The essential concerns of the current stage of this proposal are the development of carriers that can improve the efficiency of delivery of boron compounds and the dosimetric assessment of treatment feasibility. For this purpose, an specific pool of clinical cases that can benefit from this application was determined. In this work, we present the proposal and the advances related to the different stages of current research. [ABSTRACT FROM AUTHOR]

In the frame of the Argentine BNCT Project a new research line has been started to study the application of BNCT to the treatment of locoregional recurrences of HER2+ breast cancer subtype. Based on former studies, the strategy considers the use of immunoliposomes as boron carriers nanovehicles to target HER2 overexpressing cells. The essential concerns of the current stage of this proposal are the development of carriers that can improve the efficiency of delivery of boron compounds and the dosimetric assessment of treatment feasibility. For this purpose, an specific pool of clinical cases that can benefit from this application was determined. In this work, we present the proposal and the advances related to the different stages of current research. [ABSTRACT FROM AUTHOR]

Abstract: A facility for the irradiation of a section of patients'' explanted liver and lung was constructed at RA-3 reactor, Comisión Nacional de Energía Atómica, Argentina. The facility, located in the thermal column, is characterized by the possibility to insert and extract samples without the need to shutdown the reactor. In order to reach the best levels of security and efficacy of the treatment, it is necessary to perform an accurate dosimetry. The possibility to simulate neutron flux and absorbed dose in the explanted organs, together with the experimental dosimetry, allows setting more precise and effective treatment plans. To this end, a computational model of the entire reactor was set-up, and the simulations were validated with the experimental measurements performed in the facility. [Copyright &y& Elsevier]

A metabolite of the fungus Meira argovae Boekhout, Scorzetti, Gerson & Sztejnberg (Exobasidiomycetidae) was assayed as an antagonist of mites. Separation of extracted fungal metabolites by reversed phase liquid chromatography (RPLC), with subsequent testing of the obtained fractions, allowed us to isolate a single mite-antagonistic fraction (also active against a bacterium) that primarily includes one major component. This active compound (herein termed 'argovin') was identified by analyzing its spectral characteristics as 4,5-dihydroxyindan-1-one, which has previously only been described as a product of chemical reactions. The growth rate of the fungus was higher at a neutral pH than at an acidic one. Meira argovae adjusts the pH of its media to values optimal for its colony growth and toxic secretions. RPLC-cleaned argovin at 0.2 mg ml−1 killed 100% of a population of the citrus rust mite, Phyllocoptruta oleivora (Ashmead) (Acari: Eriophyidae). This trait may be used to control citrus rust mites in the field, as well as for toxin production for industrial and pharmaceutical uses. [ABSTRACT FROM AUTHOR]

Aims: The fungus Meira geulakonigii has been shown to reduce populations of citrus rust mite (CRM; Phyllocoptruta oleivora) on citrus leaves and fruits, in both the field and laboratory. However, attempts to isolate the fungus from leaves and fruits have been unsuccessful. The aims of this study were therefore to determine whether M. geulakonigii is a citrus endophyte, and to assess possible mechanisms involved in its mite-antagonist activity. Methods and Results: A quantitative real-time PCR and regular PCR approaches were developed to detect M. geulakonigii in both the field and laboratory. The fungus was detected throughout. Different methods revealed that M. geulakonigii is an endophyte, which colonizes both the peel of grapefruits. Applications of conidia protected the grapefruits against CRM, and fungal secretions extracted from growth media caused 100% CRM mortality. Conclusions: Meira geulakonigii is a beneficial endophyte of grapefruits that colonizes the fruit’s peel, and protects it from CRM. Significance and Impact of the Study: Findings from this study demonstrate the endophytic nature of M. geulakonigii in its interaction with grapefruits. In addition, a molecular approach was developed to specifically detect the fungus inside the grapefruit peel. This approach can be used to assess the natural occurrence of M. geulakonigii in grapefruit. [ABSTRACT FROM AUTHOR]

Mango malformation, caused by the fungus Fusarium mangiferae, is one of the major diseases of this crop occurring worldwide. This study was conducted to investigate aspects of the epidemiology, survival and spread of the pathogen in general and specifically in seedlings, the majority of which are cultivated in infected orchards in Egypt. Survival of conidia of a representative isolate (506/2) declined very rapidly in soil under summer conditions (1·6 weeks for 50% population decline), but significantly less in controlled and winter conditions (17·9 and 15·0 weeks, respectively, for 50% population decline). Likewise, inoculum survival in naturally infected panicles on the soil surface declined faster than in those buried at 30-cm depths. Natural infections were evaluated on fruits and seeds in a heavily infected and a healthy orchard. In infected trees, the skins of all sampled fruits within a 2-m radius of infected panicles were infected, but the pathogen was not detected in the seeds, seed coats or flesh. The pathogen was not detected in any parts of fruits from a healthy orchard. Vegetatively malformed mango seedlings, growing under infected trees bearing infected panicles, were sampled in two locations in Egypt to determine whether infection in seedlings was systemic (evenly distributed within plant tissue) or whether the pathogen originated from malformed panicles. According to PCR-specific primer amplification, the pathogen was detected in 97% of seedling apical meristems, declining gradually to 5% colonization in roots. It was concluded that inoculum of the pathogen originates from infected panicles and affects seedlings from the meristem, with infections descending to lower stem sections and roots. Minor infections of roots may occur from inoculum originating from infected panicles, but the pathogen is not seedborne. [ABSTRACT FROM AUTHOR]