Vortex loops entry into type--II superconductors

The magnetic field distribution, the magnetic flux, and the free energy of an Abrikosov vortex loop near a flat surface of type--II superconductors are calculated in the London approximation. The shape of such a vortex line is a semicircle of arbitrary radius. The interaction of the vortex half--ring and an external homogeneous magnetic field applied along the surface is studied. The magnitude of the energy barrier against the vortex expansion into superconductor is found. The possibilities of formation of an equilibrium vortex line determined by the structure of the applied magnetic field by creating the expanding vortex loops near the surface of type--II superconductor are discussed.Comment: LaTeX file ( 22 pages & 7 figures ); the required TeX style file "bezier.sty" is attached; accepted for publication in Physica

COMPETITIVE ABILITY OF MAIZE IN MIXTURE WITH CLIMBING BEAN IN ORGANIC FARMING

Intercropped crops represent an important production system in organic farming, especially maize/climbing bean mixture due to its high content of protein in bean seeds for human diet, and producing silage for ruminants. To test this hypothesis, the effects of maize (Zea mays L.) sown as a sole crop and maize/climbing bean (Phaseolus vulgaris L. cv. Cipro) mixtures on maize plant height, maize leaf area index, bean leaf area index and grain yield were investigated in field experiments on an organic farm following accepted rules of certification. The maize/climbing bean mixture increased maize plant height as well as maize and bean leaf area and reduced maize grain yield in comparison with maize sown as sole crop, but 477.5 kg ha-1seed yield of bean sown in mixture was obtained. Maize was a stronger competitor than bean. The overall conclusion is that maize/bean mixture has promise for producing valuable yield of maize and bean, but mixtures needs further investigation

The response of two legume crops (hyacinth bean and Kidney bean) to the parasitism of field dodder (_Cuscuta campestris_)

Abstract: Microscopic examinations and chemical studies were performed to study the response of two legume crops, hyacinth bean (_Lablab purpureus L._) Sweet and kidney bean (_phaseolus vulgaris L._) to the filed dodder (FD) (_Cuscuta campestris Yuncker_) parasitism. Hyacinth bean, showing no effective resistance mechanisms,was found to be a highly susceptible host to FD. However, kidney bean, displaying resistant reactions towards the parasitism of FD,was found to be an incompatible host.The possible reasons for the resistance of kidney bean to FD were anatomical (hypersensitivity) and chemical (high contents of phenolic acids and lignin) stimulated defence mechanisms, which developed during the actual intrusion of FD haustorial cells inside its tissues

Relationship Between Physiological Characteristic and Bean Quality on Some Cocoa Clones (Theobroma Cacao L.)

Photosynthesis is one of the physiological process that influence the bean weight and this process related with the efectiveness of the stomata character and chlorophyll content in the leaves. The research was conducted at Kaliwining Research Station, Indonesian Coffee and Cocoa Research Institute. Design of experiment was randomized complete block design (RCBD) consisted of six clones as treatment were Sulawesi 1, Sulawesi 2, Sca 6, ICS 60, TSH 858, ICCRI 03, PA 300. Each treatment was replicated three times. Stomata resistance diffusion, tranpiration,the content of chlorophyll a, chlorophyll b, chlorophyll total (a+b), bean number and bean weight were observed. The resuts of experiment showed that difference in chlorophyll a, chlorophyll b, chlorophyll total (a+b), stomata resistance diffusion, bean number and bean weight existed within six clones tested. Transpiration rate did not show the significantly different between six clones tested. Sulawesi 1 showed the highest content of chlorophyll a and ICS 60 and ICCRI 03 showed higher content of chlorophyll b than the other clones. Chlorophyll a, b and total (a+b) showed positively influence on bean number and bean weight. Transpiration rate had negatively influence to bean number per pod, on the otherhand it showed positively influence to bean weight. Chlorophyll total (a+b) showed high genetic variance (σg2), high phenotypic variance (σf2) and high estimated value of heritability (H). The chlorophyll a,b had moderate genetic variance, moderate phenotypic variance and high of estimated value of heritability. Chlorophyll total (a+b) could be used a selection criteria based on the value of correlation, genetic variance, phenotypic variance and estimated value of heritability would give high opportunity in selection process

Microclimate modification and insect pest exclusion using agronet improve pod yield and quality of french bean

French bean [Phaseolus vulgaris (L.)] is among the leading export vegetable in Africa, mostly produced by small-scale farmers. Unfavorable environmental conditions and heavy infestations by insect pests are among the major constraints limiting production of the crop. Most French bean producers grow their crop in open fields outdoors subject to harsh environmental conditions and repeatedly spray insecticides in a bid to realize high yield. This has led to rejection of some of the produce at the export market as a result of stringent limits on maximum residue levels. Two trials were conducted at the Horticulture Research and Teaching Field, Egerton University, Kenya, to evaluate the potential of using agricultural nets (herein referred to as agronets) to improve the microclimate, reduce pest infestation, and increase the yield and quality of French bean. A randomized complete block design with five replications was used. French bean seeds were direct-seeded, sprayed with an alpha-cypermethrin-based insecticide (control), covered with a treated agronet (0.9 mm 3 0.7 mm average pore size made of 100 denier yarn knitted into a mesh impregnated with alpha-cypermethrin), or covered with an untreated-agronet (0.9 mm 3 0.7 mm average pore size made of 100 denier yarn knitted into a mesh not impregnated with insecticide). Alpha-cypermethrin and agronets were manufactured by Tagros Chemicals (India) and A to Z Textile Mills (Tanzania), respectively. Covering French bean with the agronets modified the microclimate of the growing crop with air temperature increased by '10%, relative humidity by 4%, and soil moisture by 20%, whereas photosynthetic active radiation (PAR) and daily light integral (DLI) were decreased by '1% and 11.5%, respectively. Populations of silverleaf whitefly [Bemisia tabaci (Gennadius)] and black bean aphids [Aphis fabae (Scopoli)] were reduced under agronet covers as contrasted with control plots. Furthermore, populations of both pests were reduced on French bean grown under impregnated agronets compared with untreated agronets, but only on three of the five sampling dates [30, 44, and 72 days after planting (DAP)] for silver leaf whitefly or at only one of the five sampling dates (30 DAP) for black bean aphid. Covering French bean with agronets advanced seedling emergence by 2 days and increased seedling emergence over 90% compared with control plots. French bean plants covered with both agronet treatments had faster development, better pod yield, and quality compared with the uncovered plants. These findings demonstrate the potential of agronets in improving French bean performance while minimizing the number of insecticide sprays within the crop cycle, which could lead to less rejection of produce in the export market and improved environmental quality. (Résumé d'auteur

THE IMPACT OF BEAN RESEARCH IN HONDURAS

Since the mid-1980s, bean research in Honduras has focused on the development of improved varieties resistant to key diseases, principally Bean Golden Yellow Mosaic Virus (BGYMV), one of the main constraints to bean production in the country. This paper presents evidence of recent adoption rates of improved bean varieties, the farm-level economic impact of adoption, and the ex post rate of return to bean research in Honduras from 1982-2010. Results from a 2001 farm-level survey in the two principal bean-producing regions in Honduras show that 46 to 51% of bean farmers (depending upon the season) have adopted an improved variety, and that adoption is scale-neutral with respect to farm-size and market orientation. Due to the potential problem of sample selection bias in the adoption of disease-resistant varieties, the farm-level impact of the new varieties was estimated using experimental data to approximate the yield differential between resistant and non-resistant varieties under disease pressure, and survey data was used to approximate the frequency of disease incidence in farmers' fields. An expected utility framework assuming risk neutrality demonstrates that adopters gain an average of 20% in bean income from increased yield stability under disease pressure, although these gains are reduced by 7 to 16% due to market price discounts for the resistant varieties. Under base-level assumptions, the economic rate of return bean research in Honduras during the period 1982-2010 is 40 %.Crop Production/Industries, Research and Development/Tech Change/Emerging Technologies,

Faba bean as a novel brewing adjunct:consumer evaluation

The starch in the grains of legumes, such as faba bean (Vicia faba L.), offers an environmentally sustainable raw material for the brewing industry as their entire nitrogen fertiliser requirement can be provided by the natural process of biological nitrogen fixation. Faba bean is, therefore, distinguished from species such as spring barley (Hordeum vulgare L.), which require large amounts of synthetic nitrogen fertiliser. Consumer analysis of beer produced with faba bean as an adjunct compared with barley malt beers has not previously been assessed. This study evaluated the potential of beers brewed using 30% (w/w) dehulled bean (kernel) flour as an adjunct to malted barley, using a series of quantitative sensory tests. The first, a blind acceptance test with inferred preference, found no statistically significant difference in the taste score of the bean kernel flour adjunct beer when compared with conventional beer. In the second acceptance test, the knowledge that the beer was produced using beans did not affect the overall consumer impression of the beer, regardless of how this information was presented. These results suggest that the use of faba beans in brewing does not impact negatively on the taste or acceptability of the resultant bee