Ethylene Synthesis and Sensitivity in Crop Plants

The gaseous plant hormone ethylene is a small molecule that regulates developmental change. Research was conducted in three areas: sensitivity, synthesis, and alterations to synthesis. Vegetative pea plants were more sensitive than radish plants to atmospheric ethylene. Light intensity did not affect ethylene sensitivity. Ethylene synthesis rates were measured for unstressed cotton, corn, soybean, and tomato plants. The per-plant ethylene synthesis rate ranged from 0.1-80 pmol plant-1 s-1. However, when normalized to net photosynthetic rate, this range was 1-4 µmol of ethylene synthesis per mol of CO2 uptake. Diurnal cycles in ethylene synthesis were present in all crops studied. These cycles were disrupted by drought stress and were attenuated when synthesis rates underwent large changes. Drought stress decreased synthesis in cotton. Flooded corn and soybean had increased synthesis. Blocked perception had no effect on ethylene synthesis or net photosynthetic rate in healthy unstressed plants

Cell synchronization and dynamic G-banding of equine chromosomes by bromodeoxyurldine

Both dynamic G-banding and cell synchronization produced by bromodeoxyuridine (BrdU), were applied to equine chromosomes. BrdU incorporated during the first half of the S-phase is taken up into the R-bands that are early replicating. These bands, which have incorporated BrdU, cannot contract as usual and remain elongated; only the other regions of the chromosome, i.e., the G-bands, contract normally and are sharply defined. BrdU also can be used for cell synchronization. The addition of BrdU in a high concentration, 15 hours before harvest, and its removal 11 hours later, has two effects: initially the BrdU is incorporated during the first part of the S-phase and then it blocks the cells at mid-S-phase. Within the cell cycle, mid-S-phase appears to be the most vuinerable time to various blocking agents. To differentiate the regions of BrdU incorporation from those that have not been substituted, the fluorescence-photolysis-Glemsa (FPG) technique was applied as modified for horse chromosomes. This dynamic technique, which produces many prometaphase and prophase chromosomes showing very sharp G-bands, is certain to enhance the accuracy of cytogenetic analysis and aid in the standardization of equine chromosome

High resolution R-bands produced in equine chromosomes after incorporation of bromodeoxyuridine

Cell synchronization was used to obtain an adequate percentage of very long chromosomes in equine mitotic spreads. Reported here is our variation, adapted to horse chromosomes, of a method using excess thymidine followed by bromodeoxyuridine incorporation. This technique routinely yields excellent quality cells, predominantly in prometaphase and prophase. Among other differences with the standard technique, this addltion does not use Colcemid, which, in addltion to Inhibiting spindle fiber formation, also increases chromosome contraction resulting in thicker and thus fewer bands. Consequently, horse prometaphase chromosomes, which have incorporated BrdU in the late-S-phase, are very long and display a large number of R-bands after the fluorescence-photolysis Glemsa method. This technique should definitely be useful for the analysis of structural anomalies and the standardization of equine R-band

Light level does not alter ethylene sensitivity in radish or pea

Ethylene accumulation occurs in many plant growth environments. In some instances, low photosynthetic photon flux (PPF) is also a stress factor. Ethylene helps regulate the shade-avoidance mechanism and synthesis rates can be altered by light. We thus hypothesized that ethylene sensitivity in whole plants may be altered in low light. Radish (Raphanus sativus) and pea (Pisum sativum) plants were selected as models due to their rapid growth, use in previous studies and difference in growth habit. We first characterized radish and pea sensitivity to ethylene. Radish vegetation was less sensitive to ethylene than pea vegetation. Pea reproductive yield was highly sensitive. Plants grown under low light levels are typically etiolated and less robust than plants grown under higher light. In a second series of studies we examined the interaction of ethylene No whole plant PPF-ethylene interaction in radish and pea. 2 (50 ppb pea, 200 ppb radish) with PPFs from 50 to 400 µmol m . There was no statistically significant interaction between ethylene sensitivity and PPF, indicating that high PPF does not mitigate the detrimental effects of chronic low-level ethylene exposure. This also suggests there is no crosstalk between the shade avoidance pathway and the primary ethylene signaling pathway

Dwarf Crop Response to a 16 or 24 hr Photoperiod Under Low-Light Conditions

Plants were grown in ambient lab conditions under cool white fluorescent lights at a PPF of 90 µmol m-2 s-1 and a photoperiod of either 16 or 24 hours. Plants were watered with tap water once each day. Nutrients were supplied by Osmocote Plus slow-release fertilizer mixed into the media at approximately 7 g per 2 L pot.Rice, and soybeans become excessively elongated and could not practically be grown at this low light level. Tomatoes, peppers and peas were successfully grown. The life cycle for peas and peppers was two to three times longer than in higher light. Triton pepper plants grown under a continuous photoperiod were slightly taller than those grown using a 16 hr photoperiod. Micro-Tina tomatoes grown under continuous light had no chlorosis but were twice as tall as those grown using the 16 hr photoperiod. Peas were the most adapted crop. Neither the height nor the life cycle was extended by low light nor affected by photoperiod length. The yield of peas, however, is proportional to the light level and, although less than peas grown under high light, was the same between the two photoperiods

FiPaWeb: method to reduce the complexity of web search

In this work the FiPaWeb method is proposed to group the pages; and at the same time keep the overlap between them; without losing information. The method has five stages. In the first stage the web search is performed. In the second stage the relevant pages are selected. In the third stage the value of each service is determined for each page. In the fourth stage the pages are grouped based on established criteria. Finally, in the fifth stage, the system accesses the groups that contain only the information requested by the user in a query. (Párrafo extraído del texto a modo de resumen)Sociedad Argentina de Informática e Investigación Operativa (SADIO

Interpersonal Trust in Virtual Software Development Teams: A Systematic Mapping Study

Context: The progress of Information and Communication Technologies has greatly promoted the relationships among people of different geographical regions. Under this novel context, new settings of software development arise, known as virtual teams, a team of geographically dispersed developers. Objective: to assess the impact of virtual team’s interper-sonal trust on software development process. Method: We conducted a systematic mapping study of peer-reviewed literature up to August 2016. Results: We reviewed 41 primary studies. Some highlights are that virtual team effectiveness is the most affected aspect by the lacking of interpersonal trust, while face-to-face meeting is the most mentioned work strategy to mitigate this problem. Conclusions: This study corroborates the impact of interpersonal trust on virtual software development teams. We identified some work strategies but few advanced tools to mitigate the problems derived from the lack of interpersonal trust.Sociedad Argentina de Informática e Investigación Operativ

Interpersonal Trust in Virtual Software Development Teams: A Systematic Mapping Study

Context: The progress of Information and Communication Technologies has greatly promoted the relationships among people of different geographical regions. Under this novel context, new settings of software development arise, known as virtual teams, a team of geographically dispersed developers. Objective: to assess the impact of virtual team’s interper-sonal trust on software development process. Method: We conducted a systematic mapping study of peer-reviewed literature up to August 2016. Results: We reviewed 41 primary studies. Some highlights are that virtual team effectiveness is the most affected aspect by the lacking of interpersonal trust, while face-to-face meeting is the most mentioned work strategy to mitigate this problem. Conclusions: This study corroborates the impact of interpersonal trust on virtual software development teams. We identified some work strategies but few advanced tools to mitigate the problems derived from the lack of interpersonal trust.Sociedad Argentina de Informática e Investigación Operativ

Sistema de gestión administrativa utilizando blockchain

En la actualidad, en la mayoría de las actividades diarias y rutinarias que desarrolla un ser humano interviene la tecnología. Sin embargo, aún quedan actividades donde la misma no está presente y en los tiempos que corren ésta es crucial para el seguro y correcto funcionamiento de dichas tareas. Así por ejemplo, la Facultad de Ciencias Exactas, Físicas y Naturales de la Universidad Nacional de San Juan, que si bien posee un ágil y moderno sistema online para realizar las gestiones académicas, carece de uno que permita realizar trámites administrativos en los que se requiera presentar y certificar antecedentes. En la última década se han ido popularizando los términos blockchain y bitcoin. Así por ejemplo numerosas empresas, organizaciones, instituciones gubernamentales e incluso las educativas, están haciendo uso de esta emergente tecnología para llevar a cabo sus transacciones a diario. Las aplicaciones basadas en blockchain están aportando especificaciones, las cuales hasta hace poco tiempo eran impensables para los sistemas de gestión administrativa y académica, tales como la permanencia, transparencia e inmutabilidad. Estas características permiten que estos sistemas sean ideales para el tipo de necesidades planteadas en la facultad. Este trabajo presenta un sistema que gestiona el procesamiento automático de antecedentes personales.Eje: Innovación en Sistemas de Software.Red de Universidades con Carreras en Informátic

Sistema de gestión administrativa utilizando blockchain

En la actualidad, en la mayoría de las actividades diarias y rutinarias que desarrolla un ser humano interviene la tecnología. Sin embargo, aún quedan actividades donde la misma no está presente y en los tiempos que corren ésta es crucial para el seguro y correcto funcionamiento de dichas tareas. Así por ejemplo, la Facultad de Ciencias Exactas, Físicas y Naturales de la Universidad Nacional de San Juan, que si bien posee un ágil y moderno sistema online para realizar las gestiones académicas, carece de uno que permita realizar trámites administrativos en los que se requiera presentar y certificar antecedentes. En la última década se han ido popularizando los términos blockchain y bitcoin. Así por ejemplo numerosas empresas, organizaciones, instituciones gubernamentales e incluso las educativas, están haciendo uso de esta emergente tecnología para llevar a cabo sus transacciones a diario. Las aplicaciones basadas en blockchain están aportando especificaciones, las cuales hasta hace poco tiempo eran impensables para los sistemas de gestión administrativa y académica, tales como la permanencia, transparencia e inmutabilidad. Estas características permiten que estos sistemas sean ideales para el tipo de necesidades planteadas en la facultad. Este trabajo presenta un sistema que gestiona el procesamiento automático de antecedentes personales.Eje: Innovación en Sistemas de Software.Red de Universidades con Carreras en Informátic