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Stepper Motor and 7 Segment Display Control with Parallel Port

Thursday, June 21, 2012 Posted by Glenn Von Posadas 0 comments

Note: since I am a bit busy in my school, I will be posting some logic(advanced) stuffs here on my blogsite by other authors on the web. :) Hopefully, I will be able soon to post my original works here. :)

This project is about controlling a stepper motor and seven segment display via the parallel port. I am going to explain how to control a stepper motor and seven segment display. Here also you can find some more information about the parallel port configuration and such. Also I will describe the seven segment display.
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Figure 1 – Circuit

1. What is a Stepper Motor?

A stepper motor is an electromechanical device which converts electrical pulses into discrete mechanical movements. The shaft or spindle of a stepper motor rotates in discrete step increments when electrical command pulses are applied to it in the proper sequence. The motor's rotation has several direct relationships to these applied input pulses. The sequence of the applied pulses is directly related to the direction of motor shaft's rotation. The speed of the motor shaft's rotation is directly related to the frequency of the input pulses, and the length of rotation is directly related to the number of input pulses applied.

1.1 Stepper Motor Advantages & Disadvantages

Of course stepper motor systems are have some advantages & disadvantages. Here you can realize that it comes with so few disadvantages.

Advantages

  1. The rotation angle of the motor is proportional to the input pulse.
  2. The motor has full torque at standstill (if the windings are energized)
  3. Precise positioning and repeatability of movement since good stepper motors have an accuracy of 3% to 5% of a step, and this error is non-cumulative from one step to the next
  4. Excellent response to starting/stopping/reversing
  5. Very reliable since there are no contact brushes in the motor. Therefore the life of the motor is simply dependent on the life of the bearing
  6. The motor's response to digital input pulses provides open-loop control, making the motor simpler and less costly to control
  7. It is possible to achieve very low speed synchronous rotation with a load that is directly coupled to the shaft
  8. A wide range of rotational speeds can be realized as the speed is proportional to the frequency of the input pulses.

Disadvantages

  1. Resonances can occur if not properly controlled
  2. Not easy to operate at extremely high speeds. For this process you need to use DC motors.

1.2 Stepper motor characteristics

Stepper motors are constant-power devices (power = angular velocity x torque). As motor speed increases, torque decreases. The torque curve may be extended by using current limiting drivers and increasing the driving voltage. Steppers exhibit more vibration than other motor types, as the discrete step tends to snap the rotor from one position to another. This vibration can become very bad at some speeds and can cause the motor to lose torque. The effect can be mitigated by accelerating quickly through the problem speed range, physically damping the system, or using a micro-stepping driver. Motors with greater number of phases also exhibit smoother operation than those with fewer phases. Stepping motors are suitable for translating digital inputs into mechanical motion. In general, there are three types of stepping motor:
  1. VR (Variable Reluctance) stepping motors
  2. Hybrid Stepping motors
  3. PM (Permanent Magnet) Stepping motors
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Table 1. Stepping Motor Characteristics Comparison
Figure 2 and 3 are used to explain the operation of a simplified stepping motor (90°/step). Here the A coil and Bcoil are perpendicular to each other. If either A or B coil is excited (a condition which is known as single-phase excitation), the rotor can be moved to 0°, 90°, 180°, 270° degree position depending on the current’s ON/OFF conditions in the coils.
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Figure 2 - Single-phase excitation
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Figure 3 - Single-phase coil schematic

1.3 Two-phase stepper motors

There are two basic winding arrangements for the electromagnetic coils in a two phase stepper motor: bipolar and unipolar.

Unipolar Motors

A unipolar stepper motor has logically two windings per phase, one for each direction of current. Since in this arrangement a magnetic pole can be reversed without switching the direction of current, the commutation circuit can be made very simple (e.g. a single transistor) for each winding. Typically, given a phase, one end of each winding is made common: giving three leads per phase and six leads for a typical two phase motor. Often, these two phase commons are internally joined, so the motor has only five leads.
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Figure 4 – It is possible to take a stepper motor from an old floppy drive
A microcontroller or stepper motor controller can be used to activate the drive transistors in the right order, and this ease of operation makes unipolar motors popular with hobbyists; they are probably the cheapest way to get precise angular movements. (For the experimenter, one way to distinguish common wire from a coil-end wire is by measuring the resistance. Resistance between common wire and coil-end wire is always half of what it is between coil-end and coil-end wires. This is due to the fact that there is actually twice the length of coil between the ends and only half from center - the common wire - to the end.)
Unipolar stepper motors with six or eight wires may be driven using bipolar drivers by leaving the phase commons disconnected, and driving the two windings of each phase together. It is also possible to use a bipolar driver to drive only one winding of each phase, leaving half of the windings unused.

Bipolar motor

Bipolar motors have logically a single winding per phase. The current in a winding needs to be reversed in order to reverse a magnetic pole, so the driving circuit must be more complicated, typically with an H-bridge arrangement. There are two leads per phase, none are common.
Static stictional effects using an H-bridge have been observed with certain drive topologies. See DuBord phenomenon. Because windings are better utilised, they are more powerful than a unipolar motor of the same weight.

8-lead stepper

An 8 lead stepper is wound like a unipolar stepper, but the leads are not joined to common internally to the motor. This kind of motor can be wired in several configurations:
  • Unipolar.
  • Bipolar with series windings. This gives higher inductance but lower current per winding.
  • Bipolar with parallel windings. This requires higher current but can perform better as the winding inductance is reduced.
  • Bipolar with a single winding per phase. This method will run the motor on only half the available windings, which will reduce the available low speed torque but require less current.
The coil schematic of a bipolar stepper motor is shown below:
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Figure 5 - Bipolar Stepper motor Coil schematic
Sending 1011 to the AABB pins will rotate the motor to a particular location, by energizing Coil A in a particular direction. Then rotating this sequence to 0111, will energize Coil B in the same direction. Motor will turn by another step. Then, another rotated sequence of 1110 will energize the Coil A with a reversed direction as compared to the previous one, so the motor will continue with another step in the same direction. Then 1101 will energize the Coil B in the reverse direction, and one full rotation will be completed, if the rotor has only two teeth. However, commercial motors have more than two teeth, and they turn by steps of typically 1.8° instead of 90°.

2. What is SN74LS47?

The SN74LS47 are Low Power Schottky BCD to Seven-Segment Decoder /Drivers consisting of NAND gates, input buffers and seven AND-OR-INVERT gates. They offer active LOW, high sink current outputs for driving indicators directly. Seven NAND gates and one driver are connected in pairs to make BCD data and its complement available to the seven decoding AND-OR-INVERT gates. The remaining NAND gate and three input buffers provide lamp test, blanking input / ripple-blanking output and ripple-blanking input. The circuits accept 4-bit binary-coded-decimal (BCD) and, depending on the state of the auxiliary inputs, decodes this data to drive a seven-segment display indicator. The relative positive-logic output levels, as well as conditions required at the auxiliary inputs, are shown in the truth tables. Output configurations of the SN74LS47 are designed to withstand the relatively high voltages required for seven-segment indicators.
Here in Figure 6 you can see connection diagram of SN74LS47 and pin information. You will find the circuit diagram later on the document. With truth table (Figure 7) you can find out what values are for which letter. Since the SN74LS47 is a BCD converter the table is going to be needed to make work easier.
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Figure 6 – SN74LS47 Connection Diagram
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Figure 7 – Truth Table for BCD Conversion

2.1 The BCD Number System

You should now be familiar with the Binary, Decimal and Hexadecimal Number System. If we view single digit values for hex, the numbers 0 - F, they represent the values 0 - 15 in decimal, and occupy a nibble. Often, we wish to use a binary equivalent of the decimal system. This system is called Binary Coded Decimal or BCD which also occupies a nibble. In BCD, the binary patterns 1010 through 1111 do not represent valid BCD numbers, and cannot be used.
Conversion from Decimal to BCD is straightforward. You merely assign each digit of the decimal number to a byte and convert 0 through 9 to 0000 0000 through 0000 1001, but you cannot perform the repeated division by 2 as you did to convert decimal to binary. Let us see how this works. Determine the BCD value for the decimal number 5,319. Since there are four digits in our decimal number, there are four bytes in our BCD number. Since computer storage requires the minimum of 1 byte, you can see that the upper nibble of each BCD number is wasted storage. BCD is still a weighted position number system so you may perform mathematics, but we must use special techniques in order to obtain a correct answer.

3. What is SN74LS244N?

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Figure 8 - SN74LS244N Connection Diagram
In Figure 8 you can see the logic inside the SN74LS244N and the function table. There is a tricky point here. Let’s think on this way, the SN74LS244N has 2 different sides. After the right connections such as GND and VCC connections, 2 more steps will be needed.
First, to activate the left side of it first pin is needed to connected to GND. Second, to activate the right side nineteenth pin is needed to connect to GND. Then you can you see outputs and inputs together or outputs are not going to be working.

4. Seven Segment LED Display

Once seven segment LED displays became readily available, a simple IC known as a "BCD to seven segment decoder" was quickly developed to simplify their use. Binary formatted data presented to this IC's inputs results in the IC's outputs being placed into the correct state to display the equivalent numeral (0 to 9) on a seven-segment display.
Although BCD to seven-segment decoder ICs are available without built in latches, this particular IC includes a built in 4-bit latch which we will make use of in later examples. For now the latch is set to simply allow input data to freely pass through to the decoder.
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Figure 9 – Common Cathode & Common Anode
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Figure 10 – BCD Input Data

5. How the Parallel Port Works

Parallel port is a simple and inexpensive tool for building computer controlled devices and projects. The simplicity and ease of programming makes parallel port popular in electronics hobbyist world. The parallel port is often used in Computer controlled robots, Atmel/PIC programmers, home automation, etc.
Everybody knows what a parallel port is, where it can be found, and for what it is being used. The primary use of the parallel port is to connect printers to the computer and it is specifically designed for this purpose. Thus it is often called as printer port or Centronics port (this name came from a popular printer manufacturing company 'Centronics' who devised some standards for parallel port). You can see the parallel port connector in the rear panel of your PC. It is a 25 pin female (DB25) connector (to which printer is connected). On almost all the PCs only one parallel port is present, but you can add more by buying and inserting ISA/PCI parallel port cards.
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Figure 11 – Parallel port connection of this project

5.1 Parallel Port Modes

The IEEE 1284 Standard which has been published in 1994 defines five modes of data transfer for parallel port. They are,
  1. Compatibility Mode
  2. Nibble Mode
  3. Byte Mode
  4. EPP
  5. ECP

5.2 Hardware

The pin outs of DB25 connector is shown in the picture below. And for this project from D0 to D3 is used for stepper motor pulses and from D4 to D7 is used for 7 segment control. (Look at Figure 11)
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Figure 12 – DB25 Connector
The lines in DB25 connector are divided in to three groups, they are
  1. Data lines (data bus)
  2. Control lines
  3. Status lines
As the name implies, data is transferred over data lines, Control lines are used to control the peripheral and of course, the peripheral returns status signals back computer through Status lines. These lines are connected to Data, Control And Status registers internally . The details of parallel port signal lines are given below.
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Figure 13 – DB25 Connector Pins

5.3 Parallel Port Registers

As you know, the Data, Control and status lines are connected to there corresponding registers inside the computer. So by manipulating these registers in program, one can easily read or write to parallel port with programming languages like C and BASIC.
The registers found in standard parallel port are,
  1. Data register
  2. Status register
  3. Control register
As there names specifies, Data register is connected to Data lines, Control register is connected to control lines and Status register is connected to Status lines. (Here the word connection does not mean that there is some physical connection between data/control/status lines. The registers are virtually connected to the corresponding lines.). So what ever you write to these registers, will appear in corresponding lines as voltages, Of course, you can measure it with a multimeter. Whatever you give to Parallel port as voltages can be read from these registers (with some restrictions). For example, if we write '1' to Data register, the line Data0 will be driven to +5V. Just like this ,we can programmatically turn on and off any of the data lines and Control lines.
There is a simple code to use LPT1 port:
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This Macro is sending the value SEND to the LPT1 port with address of 378H. By getting help from this macro you can write an assembly code and making the below circuit you can get a chance to see your parallel port is works.
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Figure 14 – Simple Circuit to test parallel port

Circuit of Project

circuit_design.jpg

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Figure 15 – Full Circuit of Project

Project by:
Samet KILICTAS



Software Developer

Turkey Turkey



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Will we recognize our loved ones when we get to heaven?

Posted by Glenn Von Posadas 0 comments


You will absolutely be able to recognize your loved ones when you get to heaven! Biblical Proofs? Here they are:

1. Luke 9:28-33 "About eight days after Jesus said this, he took Peter, John and James with him and went up onto a mountain to pray. 2As he was praying, the appearance of his face changed, and his clothes became as bright as a flash of lightning. Two men, Moses and Elijah, appeared in glorious splendor, talking with Jesus. They spoke about his departure, which he was about to bring to fulfillment at Jerusalem. Peter and his companions were very sleepy, but when they became fully awake, they saw his glory and the two men standing with him. As the men were leaving Jesus, Peter said to him, "Master, it is good for us to be here. Let us put up three shelters-one for you, one for Moses and one for Elijah." NIV

Although Peter had never met Moses and Elijah, he recognized them and suggested to build 3 tents, one for Jesus, one for Moses and one for Elijah. Not only will we be able to recognize our loved ones, we will recognize our heroes of the faith as well.

P. S. In the OT there is mention of Elijah being taken into heaven (see 2 Kings 2:11-12), however no mention is given at all concerning Moses being in heaven until Jude 9. Peter was not startled by the fact that Moses was in heaven and not in an unconscious sleep. Moses' appearance seemed completely Biblical to him.

2. Matt 28:9-10 "Suddenly Jesus met them. "Greetings," he said. They came to him, clasped his feet and worshiped him. Then Jesus said to them, "Do not be afraid. Go and tell my brothers to go to Galilee; there they will see me." NIV

When Jesus was resurrected His disciples recognized Him, unless He didn't want His identity revealed.

3. Luke 16:19-26 "There was a rich man who was dressed in purple and fine linen and lived in luxury every day. At his gate was laid a beggar named Lazarus, covered with sores and longing to eat what fell from the rich man's table. Even the dogs came and licked his sores. "The time came when the beggar died and the angels carried him to Abraham's side. The rich man also died and was buried. In hell, where he was in torment, he looked up and saw Abraham far away, with Lazarus by his side. So he called to him, 'Father Abraham, have pity on me and send Lazarus to dip the tip of his finger in water and cool my tongue, because I am in agony in this fire.' "But Abraham replied, 'Son, remember that in your lifetime you received your good things, while Lazarus received bad things, but now he is comforted here and you are in agony. And besides all this, between us and you a great chasm has been fixed, so that those who want to go from here to you cannot, nor can anyone cross over from there to us.'" NIV

The rich man recognized Lazarus when he went to heaven.

There is no doubt here. Nowhere in the Bible is there any mention that we will not be able to recognize one another in heaven. What an awesome God we have!

Are you looking forward in seeing your loved ones again when you reach heaven? Are you uncertain that you will reach heaven? If you are, why don't you accept Jesus in your heart now by answering His altar's call athttp://www.answers2prayer.org/saviours_call.html  He will give you the assurance that you are saved, through His Holy Spirit. It is Biblical: Eph 1:13-14 "Having believed, you were marked in him with a seal, the promised Holy Spirit, who is a deposit guaranteeing our inheritance until the redemption of those who are God's possession-to the praise of his glory." NIV Will you accept His invitation now?
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I believe we will. The best example we have is Jesus Himself. After His resurrection, Jesus appeared to many for 40 days before ascending to heaven. It is evident that his memory was restored and that He knew all the people He previously knew. The body Jesus had after resurrection is the same as we will have. Not only did Jesus have full memory but those who were resurrected with Him at that time and who accompanied Him to heaven, went among the people and appeared to many. It is expected that these are the elders helping Jesus in His Priestly duties, later mentioned in Revelation. Revelation makes it clear that the 4 beasts or living creatures and the 24 elders are of the saved of earth. They would need their full faculties in order to assist Jesus with His work. Never forget that Jesus is still a man.

The apostle Paul alludes to this also:

1 Corinthians 13:12 For now we see through a glass, darkly; but then face to face: now I know in part; but then shall I know even as also I am known.

One of the stories Jesus told also mentions this knowing.

Luke 16:20 And there was a certain beggar named Lazarus, which was laid at his gate, full of sores,

Luke 16:21 And desiring to be fed with the crumbs which fell from the rich man's table: moreover the dogs came and licked his sores.

Luke 16:22 And it came to pass, that the beggar died, and was carried by the angels into Abraham's bosom: the rich man also died, and was buried;

Luke 16:23 And in hell he lift up his eyes, being in torments, and seeth Abraham afar off, and Lazarus in his bosom.

Luke 16:24 And he cried and said, Father Abraham, have mercy on me, and send Lazarus, that he may dip the tip of his finger in water, and cool my tongue; for I am tormented in this flame.

Luke 16:25 But Abraham said, Son, remember that thou in thy lifetime receivedst thy good things, and likewise Lazarus evil things: but now he is comforted, and thou art tormented.

Luke 16:26 And beside all this, between us and you there is a great gulf fixed: so that they which would pass from hence to you cannot; neither can they pass to us, that would come from thence.

Luke 16:27 Then he said, I pray thee therefore, father, that thou wouldest send him to my father's house:

Luke 16:28 For I have five brethren; that he may testify unto them, lest they also come into this place of torment.

Luke 16:29 Abraham saith unto him, They have Moses and the prophets; let them hear them.

Luke 16:30 And he said, Nay, father Abraham: but if one went unto them from the dead, they will repent.

Luke 16:31 And he said unto him, If they hear not Moses and the prophets, neither will they be persuaded, though one rose from the dead.

In this story a number of things are evident. Both Lazarus and the rich man died, and both would have been buried. The scene mentioned in the story must take place therefore, after the resurrection. It is significant to the question that the rich man recognized Lazarus and could remember his family.

All this is clear evidence that we will have our memories restored and will recognize each other after the resurrection. But are you assured of being in the first resurrection, dear reader? Are you persuaded because Jesus rose from the dead? If not, answer 'The Savior's Call' in this newsletter. We have only while we live to make our peace with God and no one knows when the grim reaper will come calling.

Lance Wearmouth
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Absolutely! Scripture points to this! Genesis 25:8-9 says........"Then Abraham breathed his last and died in a good old age, an old man and full of years, and was gathered to his people. And his sons Isaac and Ishmael buried him in the cave of Machpelah...". Now notice the sequence: he died, then he was gathered to his people, then his body was buried in the cave. Although the tomb was new, somehow Abraham was now with his people.

Deuteronomy 31:16 shows that the destiny of Moses is described when God said, "Behold, you will rest with your fathers."

Judges 2:10 shows that not only do we read of individuals being "gathered" to their people, but after the death of Joshua we find an entire "generation had been gathered to their fathers."

2 Kings 22:20 says that it was a comfort when the prophetess Huldah told the good King Josiah he would be "gathered to his fathers." Now if he were not going to recognize them, why would it be a comfort at all?!

In Matthew 22:30, Jesus said, "For in the resurrection they neither marry nor are given in marriage, but are like angels of God in heaven." Now, this passage proves this point. The angels of heaven surely know and recognize each other; some are even mentioned by name in the Bible.

It is without doubt that we will recognize our friends and loved ones in heaven. None of us can fathom exactly how, but we know that we will. All our questions will be answered when that time comes. MAY ALL BE BLESSED!

DeeDee
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Romans 6: 5, "For if we have been united with Him in a death like His, we shall certainly be united with Him in a resurrection like His." Jesus was recognized in His resurrected body by His followers; since we share a resurrection like His, we, too, shall be recognized and will recognize others. Many other scriptures also attest to this fact, I believe. Especially Job, when he says, "And in my flesh I will see God." Now if he can see God IN HIS FLESH even after his death, then we shall be able to see the Lord and others in their flesh and in our flesh after our earthly lives are ended.

Besides, think about it: What logic would there be in just having a mass of people that nobody recognized in heaven! Jesus said He would give us eternal life, not eternal estrangement!

Also, at the Transfiguration, the disciples recognized Elijah and Moses talking with Jesus about His departure and how it would be accomplished in Jerusalem (Luke 9:30-31). Peter stayed awake and was impressed enough by who they were to ask Jesus if they should build 3 booths. (Ala the Feast of Tabernacles; Peter was hopelessly enmeshed in the some of that time's religiosity, until he got freed of course and really got his freedom when he had the vision of the sheet with all of the "unclean" animals in it, after the Holy Spirit came.) How did they know? They must have recognized them.

Anyway, that is my take on the question. Thanks for reading and God bless you all!
Sharon Warden
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Yes! It is written: 1 Corinthians 13:12 for now we see through a glass, darkly; but then face to face: now I know in part; but then shall I know even as also I am known.
One example would be JESUS himself. When JESUS returns and we are resurrected, we will have a body just like his.
In the story of Lazarus and the rich man, Lazarus died and his spirit was carried by the angels to the 'bosum of Abrahan.' The rich man died and was buried. Both spirits were preserved until the resurrection. The rich man knew Lazarus and talked to him. He asked Lazarus to warn his family.
There is another example about someone in Hell and asking for cold water. At the moment, I can't remember who it is. LOL!
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Yes we will know each other in heaven. The bible says we will be known as we are known now.  The only thing, we will not be married there. We will know each other, but we will be spirit beings, not human beings. That makes a big difference. We will be able to think we are somewhere
and we will be there. I can't wait, I wish I was there now.
 
Lou
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The disciples didn't have any problem recognizing Moses and Elijah.

Matthew 17:1-4, "And after six days Jesus taketh Peter, James, and John his brother, and bringeth them up into an high mountain apart, And was transfigured before them: and his face did shine as the sun, and his raiment was white as the light. And, behold, there appeared unto them Moses and Elias talking with him. Then answered Peter, and said unto Jesus, Lord, it is good for us to be here: if thou wilt, let us make here three tabernacles; one for thee, and one for Moses, and one for Elias."

Moses and Elias; Moses the giver of the law, and Elias one of the chief of the prophets: one of them had been dead near a thousand and five hundred years, and the other had been caught up to heaven, about nine hundred years before this

There will be a great re-union day with loved ones when Jesus comes for His Church. We shall be caught up TOGETHER

1Th 4:16 For the Lord himself shall descend from heaven with a shout, with the voice of the archangel, and with the trump of God: and the dead in Christ shall rise first: 1Th 4:17 Then we which are alive and remain shall be caught up together with them in the clouds to meet the Lord in the air: and so shall we ever be with the Lord. 1Th 4:18 Wherefore comfort one another with these words.

Pray that this helps you to believe that you will know your loved ones when you see them in heaven. It helps me.

In Jesus Paul Phillips

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Transfomations of Cosplay Girls

Posted by Glenn Von Posadas 0 comments


“Costume play” girls aren’t necessarily skinny or beautiful. Many of them are ordinary and overweight. But Photoshop can do miracles, creating a beauty from the beast and melting a couple of pounds with a mouse click


Cosplay Girls Transformations (28 pics)

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Bermuda Triangle: New anomalous phenomenon discovered

Posted by Glenn Von Posadas 0 comments


Bermuda Triangle: New anomalous phenomenon discovered. 45395.jpeg
Recently, American scientists who studied the sea near the famous Bermuda Triangle have found another "anomaly". They saw that the surface waters in this area are literally teeming with a wide variety of viruses. However, the viruses do not represent any danger for humans as they only interested in oceanic bacteria.

The very phrase "Bermuda Triangle" has appeared only recently - it was coined by a fan of Spiritualism and esoteric Vincent Gaddis in 1964. By this toponym he meant an area located between the island of Puerto Rico, the Florida coast and Bermuda. According to the famous mystic of the last century, this area of the Atlantic became notorious due to the fact that hundreds of ships and aircraft disappeared there. Some ships, however, were found later, but without their crews and passengers.
All this made Gaddis suggests that there was some anomaly in this area. However, he was not the first one to express this idea. In 1950 an American journalist Alexander Jones wrote an article about the mysterious disappearance of ships in this region (which he called simply and tastefully - Sea Devil). Yet, the Bermuda Triangle acquired real popularity in 1974, when Charles Berlitz, a popularizer of science, published a book under the same title where he collected descriptions of various mysterious disappearances in the area. The book immediately became a bestseller, and as a result the mysterious and dangerous Sea Devil became known to the entire world. After that different groups of scientists engaged in searching for reasons to explain these disappearances.

However, over time the skeptics slowly gained the upper hand over amateur mystics. No anomalies in this part of the ocean were found, and the U.S. Coast Guard has issued several reports according to which the disappearance of ships in the Bermuda Triangle did not occur more frequently than in other regions of the ocean, and they occurred mainly due to storms. Historians, digging in the archives, found that the area since the discovery of America was very often visited by various vessels, including pirate ones. Until the second half of the 20th century sailors made no mention of it as a mysterious place where ships were constantly perishing. Persnickety journalists analyzed Berlitz's book and found that most of the facts presented by the writer were not entirely true, and some were just made up.
By the 1990s, the interest in the Bermuda Triangle was largely exhausted. Recently, however, scientists regained interest in this area, because they did discover one anomaly there. However, it has nothing to do with the disappearance of ships and aircraft.

A team of U.S. scientists led by Professor Craig Carlson of the Bermuda Institute of Oceanology (St. George, Bermuda) have been conducting oceanographic research in the northwestern part of the Sargasso Sea for ten years, near the Bermuda Triangle and Bermuda islands. Recently a report on the work of the biologists has been published. Especially interesting in this report was the fact that, according to the observations of scientists, most numerous living organisms in the surface layers of the ocean in this region are viruses.
Interestingly enough, the dynamics of these microscopic organisms is directly linked with the seasons. For example, in the summer viruses multiply actively in the water layers at depths ranging from 60 to 100 meters, and their number is up to ten million particles per drop of water. In the winter, sometimes they did not exist in the surface layers at all as they would go into the depths, following their masters.
Read article: Lake Bailak devours vessels

The researchers analyzed the DNA of the viruses caught and found that 90 percent of them still were not known to science. However, these microorganisms, both known and unknown, did not present any danger to humans. They all belong to a group of bacteriophages, that is, the objects of their attacks are bacteria living in the ocean. Bacteriophages are known to be very old-fashioned and conservative as they do not change their habits, and do not attack other creatures. 
To be able to reproduce, bacteriophages lie in wait for unsuspecting bacteria. They attach themselves to their cell walls and enter into the victim's DNA. Furthermore, they integrate into the genome of the bacteria (which is a single circular DNA molecule, lying freely in the cytoplasm and not protected by any walls). This makes them forget about their own responsibilities and focus on producing all the necessary molecules for the assembly of new viruses. This assembly also takes place inside the bacterial cell. When the number of newborn bacteriophages reaches several million, they come from the host cell, effectively breaking it into pieces, and then go in search of new victims.
The organic molecules of the dead bacteria fill the water surrounding them, and since bacteriophages kill hundreds of thousands of cells, it is not surprising that the sea surface in this place turns into a nutrient broth. Other bacteria hurry there for a feed and quickly become prey of cunning virus. This means that the bacteriophages form a microscopic ecosystem where they live.
 
Other marine creatures, unicellular and multicellular planktonic organisms, also enjoy the fruits of their work. Some are attracted by free nutrient broth, and others - by the bacteria feeding on it. It turns out viruses create a "cafeteria" in the surface layers of the sea. Even whales and dolphins come to eat there (these, in turn, are interested in swarms of krill feeding on microplankton and fish eating krill).
Scientists were amazed by what they saw because they did not know about this role of viruses in the formation of oceanic ecosystems. According to many oceanographers, oceanic viruses are very poorly understood because they are hard to catch. But now it is clear that they are countless in all seas and oceans.

"While we cannot see them with the naked eye, viruses are the dominant form of life in the ocean. They constitute 95 percent of the total biomass of the ocean. That is, the mass of virus is even larger than the mass of krill, fish and larger animals such as whales, combined. Given the pace of virus multiplication and their number, it becomes apparent how important their role in nutrient cycling on the planet is," said one of the authors of the study of biological "anomalies" of the Bermuda Triangle Dr. Rachel Persons.
However, some experts believe that in this case there are no abnormalities specific to the Bermuda triangle as processes involving the viruses are occurring in many areas of the oceans. For example, biologists from the U.S. and Canada investigated the surface waters of the North Atlantic and reported that the most diverse viral community (129,000 genotypes) was found off the coast of British Columbia. The number of these microorganisms is also very high - approximately 50 million particles in a drop of water, which is five times greater than in the Bermuda Triangle. This "virus rage" is explained by the fact that this area has rising sea currents (upwelling), bringing nutrients from the depths of the ocean to the surface. In such areas sentient beings are more abundant and their diversity is higher than in the surrounding areas, and the virus is no exception to this rule.
It appears that the largest "virus carrier" on the planet is exactly in the oceans. It is fortunate that most of microscopic parasites living in it are not dangerous to humans.

Anton Evseev
Pravda.Ru

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