Posts Tagged ‘Science’

Cytoplasmic Male Sterility

Tuesday, February 9th, 2016

One of the most striking examples of cytoplasmic heredity can be regarded as cytoplasmic male sterility (CMS) which has been found in many plants – corn, onions, beets, flax. Consider the example of cms maize. Corn – a monoecious plant, the female flowers which are collected in the ear, and male – in a whisk. Sometimes in panicle can be immature anthers with sterile pylosobennostyami cytoplasm. Pollination with pollen from cms, taken from other plants in the progeny gives shape and with sterile pollen.

Consequently, the sign of male sterility is transmitted through the maternal line. Even when all 10 pairs of chromosomes in pollen sterile plants are replaced chromosomes of plants with normal pollen, male sterility is preserved. Cytoplasm, conditional male sterility, can be denoted by vdet and cytoplasm of normal across the beat. Genetic analysis showed that genotype of the plant also affects the sterility of pollen. Cytoplasm tsit5 causes sterility only when the genotype of recessive genes in homozygous state rfrf – tsit5 rfrf. When tsit3 RfRf or tsit5 Rfrf plants have normal pollen fertility. Hence, the Rf gene is able to restore pollen fertility.

Such relations between the cytoplasm and genotype allowed us to develop methodology and to chart the receipt of interlinear hybrids of maize using the cms lines of maize used belong to the so-called "fixer" sterility "reducers" fertility. Fertile lines and varieties, preserving when crossed with a sterile form sterility in the offspring are called "fixer" for sterility, and the lines and varieties, reducing the fertility of offspring plants with cms – "reducing" fertility. I know two types of maize male sterility. Study of Education pollen sterile forms of maize showed that the apparent violation of sporogenesis occur at various stages: some degeneration is completed at the stage of single-core pollen, others – binuclear. Great influence on the manifestation of sterility by external conditions: temperature, humidity, soil and air, as well as the duration of the day. Maize varieties with one or another type of cms have different sensitivities to environmental factors. In plants with Moldovan type cms panicle form anthers, which were not disclosed, the pollen in them unviable, although under certain conditions, can be formed and sustained. In plants with Texas style cms manifestation of sterility, to a lesser extent influenced by external factors, but a sign is expressed much: anthers strongly degenerated and never disclosed. In the selection of both types cms. In addition, there are data about the use of cms and wheat. Received sterile form by crossing two plant species – Aegilops and wheat, are working on the selection of other components for hybridisation, provide the maximum heterosis. Failed to reveal a pair of crosses, which give additional yield by 40-50%.

Maintaining The Vacuum Inside The Tube

Wednesday, January 20th, 2016

During the manufacture of the tube, the air between the two tubes is extracted or removed from the space between tubes to form a vacuum, which eliminates heat loss by conduction and convection. To maintain the vacuum inside the tube, a barium element is exposed to high temperature, which causes the bottom of the tube is covered with a layer of pure barium (silver). This layer of pure barium, is a visual indicator of the internal vacuum tube. If the color turns white silver the vacuum is lost and the tube has to be replaced. Evacuated tube components: 1. Outer tube 2. Inner tube 3.

Empty 4. Selective surface (aluminum nitrate) 5. Gletter barium (element maintains the vacuum absorption) 6. Another layer of pure barium kind of pipe is known as “heat-pipe working fluid in this type of tube is a low-glycol specific heat, which is contained in a copper capillary tube inside the vacuum tube plate absorption tube “heat pipe” is inside a glass tube which has evacuated the air to eliminate heat loss by conduction and convection. The absorber plate is made from a semiconductor coating, this special coating suitable screening to operate in high vacuum ensures high energy absorption and low loss by radiation, the result is a high utilization of available energy What are the benefits of a solar heater? Solar water heaters provide more benefits than a conventional furnace or boiler. The main tangible benefit is the savings that this equipment to stop buying gas. Another equally important benefit is the contribution that a solar heater is on reducing greenhouse gas emissions to the atmosphere (carbon dioxide, CO2), creating a healthier environment. With a solar water heater will prevent the emission into the atmosphere over 3 tons of CO2. How I can save with a solar heater? The savings you can expect from a solar water heater depends on several factors, such as team size, the amount available in your area, and very importantly, the amount of hot water they occupy and how the squatters. The minimum savings in residential equipment is 80% in the current gas consumption for heating water holding. The system pays for itself on average in one year and eight months.

Science Says

Monday, May 7th, 2012

There are many issues discussed on this website.  Topics range from dedicating a week to the conservation of polar bears to the history of ants, and how far they have come.  Thereafter, where they are going now and what we as environmentally-conscious individuals, need to understand about ants and their heritage.

As well, there are more psychological discussions on how one can scientifically become happier in their lives (again though, through a scientific approach), as well as a combination of the two – how to make the environment last longer in a very easy way; just making a few (barely noticeable) changes.

The site also has a section on politics, and a directory of endangered species.