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GINGER BEER RECIPE

Homemade Ginger Beer
(Makes 4 x 1.25 litre bottles)

Yeast Mixture
 1 teaspoon dried yeast (not Surebake type)
 1 tablespoon sugar
 1 cup warm water

Ginger Beer
 2 cups sugar
 2 tablespoons ground ginger
 1 teaspoon tartaric acid
 2 litres hot water juice and grated rind of 2 lemons
 2 litres cold water

Stir the yeast mixture ingredients together in a small bowl or cup and leave to stand for 10 minutes.
1. Place the sugar, ginger, and tartaric acid in a clean bucket.
2. Pour in the hot water and lemon juice, and stir to dissolve the sugar.
3. Add the cold water, cool to lukewarm, and add the yeast.
4. Leave in the bucket (covered with a towel) for 24 to 36 hours.
5. Strain into 4 thoroughly clean 1.25 litre softdrink bottles.
6. Fill the bottle to within 5cm of the top with extra cold water.
7. Put 1 teaspoon of sugar in each bottle and screw on washed tops.
8. Shake to dissolve the sugar.
9. Leave the bottles to stand in a warm place until they feel absolutely rigid when squeezed (this takes between 2 to 5 days to happen) then refrigerate. If the bottles are fizzy, loosen then tighten the lids several times. Consume within 2 to 3 weeks.

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구제역: Foot and Mouth disease

구제역의 의학명은 Aphtae epizooticae이다.  구제역의 common name은 입발굽병 (Foot and Mouth Disease)이다. 소나 돼지등 가축에 대한 전염성이 높은 급성(acute) 바이러스성 전염병의 하나다. 사람에게 영향을 끼치지 않는걸로 알려져 있고, 별 다른 치료를 하지 않는다.  구제역은 세계 대부분의 지역에서 발생한다. 사슴, 염소, 양, 소, 코끼리, 쥐, 고슴도치 등도 감염될 수 있고 이런 동물들이 돌아다니면서 전염시킬 수 있기 때문에 구제역이 발생하지 않던 곳에서도 갑자기 발생할 수 있다.

1897년에 프리드리히 뢰플러가 구제역의 원인은 바이러스라는 것을 발견하였다. 감염된 동물혈액을 필터에 통과시켜도 여전히 다른동물을 감염시킬 수 있을정도로 작은 바이러스 임을 확인했다.

감염된 가축은 3일도안 고열에 시달린다. 입과 발굽주변에 물집이 생기는데 입으로 거품이 많고 끈적끈적한 침을 심하게 흘린다. 발굽에서도 열과 상처가 생겨 걸음을 절뚝거린다. 체중감소를 보이기도 하며 젖소의 경우 우유생산량이 감소한다. 어린 가축의 경우 심장에 문제가 생기겨 죽기도한다.

대한민국 전역에서 구제역에 걸린 동물들을 매장하여 처분하는 가운데 동물의 배를 가르는 일등 작업에 동원된 공무원들이 스트레스 장애에 시달리고 있다. 소와 돼지의 배를 가르지 않고 묻을 경우 땅속에서 동물배에 있는 가스가 땅속에 차서 폭발이 일어날 수 도 있다. 이 작업에 동원된 사람중 대부분이 소와 돼지가 죽기전 모습이 잊혀지지 않는다며 괴로워하며 고통을 호소하고 있다.

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기침을 달고 산다..

요즘 누구에게 옮았는지 갑자기 기침을 달고산다. 수업에도 방해가 되고 사람들과 모여있으면 여러모로 모양새도 빠지는데.. 언제나려나 모르겠다.

기침은 보통 가래를 제거하거나 기도에 들어간 이물질을제거하기 위한 우리몸의 방어 장치이다. 코, 기관지, 식도 등에서 자극을 느끼면 기침 중추에 신호를 보낸다. 그러면 성대, 횡경막, 호흡근육에 명령을 내리고 기침을 하게된다.

어떤 기침은 병이 시작되는 것을 알리는 신호가 되기도 하는데.. 기침의 횟수가 늘어나고 정도가 심해지는 것은 바이러스성 호흡기 감기를 의심할수 있다.  대부분, 감기로 인한 기침은 정도가 심하지 않고 증상을 완화시켜 주는 치료만으로 1주일 이내에 호전이 되는게 정상이다. 치료후에도 호흡이 빨라지거나, 고열이 보이면 자주 진찰을 받아 폐렴같은 합병증의 여부를 꼭 확인해야 한다.

기침은 지속되는 기간에 따라 2주 이내의 급성, 2~4주 이내의 아급성, 4주 이상의 만성기침으로 분류할 수 있다. 이렇게 결정한 이유는 대개의 호흡기 바이러스 감염에 의한 기침은 길어야 2~3주 이내에 멎기 때문이다..

4주이상 지속되는 만성기침을 하는 소아는 숨어있는 호흡기 질환 혹은 전신적 질환이 있는지 진찰 및 검사를 통해 확인이 필요하다.

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질문을 남기는 방법?

‘질문을 남기는 방법’을 클릭하도록 한다.

페이지를 이동하게 되는데.. 하단에 보면 Leave a reply에 질문을 남기면 끝:).

쌤이 질문에 답을 하면 이메일로 답변이 보내질 것이니 꼭 확인을 잊지말기!

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More nitrogen than oxygen?

There are more nitrogen gases than oxygen gases in the air. Every living things on the earth need nitrogen to grow and repair. Despite, it is impossible to use these nitrogen by breathing. We gain nitrogen by eating and plants absorb nitrogen as nitrates. This is because nitrogens are slightly lighter than water or air so they tend to stay in the form of stable gases. If any one of these living things die, nitrogens are returned back to the soil and air by decomposers like bacteria and fungi. These decomposers are very important. They break down all the dead materials and releases essential elements and compounds (like nitrogen and carbon) back to it’s cycle.

Nitrogen cycle

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Nebulae

Combined X-Ray and Optical Images of the Crab Nebula

http://www.hubblesite.org/gallery/album/nebula/pr2002024a/

The word “nebula” is derived from the Latin word for “clouds”. Indeed, a nebula is a cosmic cloud of gas and dust floating in space. A nebula is a huge, diffuse cloud of gas and dust in intergalactic space. The gas in nebulae (the plural of nebula) is mostly hydrogen gas (H2).

More than one nebula are called nebulae. Nebulae are the basic building blocks of the universe. They contain the elements from which stars and solar systems are built.

They glow with rich colours of reds, blues and greens with swirls of light. Stars inside these clouds of gas cause them to glow in colours.

Most nebulae are composed of about 90% hydrogen, 10% helium, and 0.1% heavy elements such as carbon, nitrogen, magnesium, potassium, calcium, iron. These clouds of matter are also quite large. In fact, they are among the largest objects in the galaxy.

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How do we see and learn? (Part 3: Memory)


Everyone wants to learn faster and effectively.

One way is to understand how the learner’s brain processes in the learning environment. Learning is the process of taking new information in your working memory and integrating it with existing knowledge in your long-term memory.  Once it’s in long-term memory you can recall it and transfer the knowledge to the real world.


  • Working memory:  Your working memory is good at processing information, but it can only hold so much at one time.  All of your active thinking happens in the working memory.
  • Long-term memory:  Your long-term memory is your storage center and holds your existing knowledge.  In the learning process, you are connecting the new information to prior knowledge.  As you actively process information, you are swapping it between working and long-term memory.

The working memory is like a white board where you can do a lot of calculations and diagramming on the fly.  On the white board, you need space to both write down information (temporary storage) and do your problem-solving (active processing).

Often the problem is that you only have so much space.  As the white board gets cluttered with information, you run out of room to work.  That means you need to record the important information and free up space to do more work on the white board.

One way to capture the information is to create post-it notes (long-term memory) to record the information on the white board.  Once you you have the notes, you are free to erase the white board and do more work.  And, if you needed to recall what you did earlier, all you have to do is look at one of your notes.


As you go through an learning process, what you see and hear enters your working memory where it is temporarily stored.  Your brain actively processes the new information and integrates it with what you have stored in your long-term memory.

So, your brain is doing these things:

  1. Receiving new information
  2. Actively processing the information
  3. Integrating the information with long-term memory

(ref: http://www.articulate.com/rapid-elearning/2007/10/)

There are numerous ways been suggested by the researchers about effective ways to transfer information to the learners. These are used to promote clear processing and life long memory of the information and teachers in classroom happen to use coloured movie clips and pens. Most of the schools have recognized the importance in providing resources and been proved to be effective.

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How do we see? (Part2: Brain and vision)

Colour blindness and night blindness

Most forms of colour blindness, an inherited inability to distinguish between certain colours, result from the absence or a deficiency of one of the three cone photopigments. The most common type is red-green colour blindness, in which a photopigment sensitive to orange-red light or green light is missing. As a result, the person cannot distinguish between red and green. Prolonged vitamin A deficiency and the consequent below normal amount of rhodopsin may cause night blindness – an inability to see well at low light levels.

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The visual pathway

After considerable processing of visual signals in the retina at synapses among the various types of neurons, the axons of retinal ganglion cell provide output from the retina to the brain.

They exit the eyeball as the optic nerve (cranial nerve II).

(http://www.msstrength.com/ms-optic-nerve-attacks-and-symptoms/)

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Process of Visual Input in the Retina

Within the retina, certain features of visual input are enhanced while other features may be discarded. This is because there are only 1million ganglion cells but 126 million photoreceptors.

Once receptors in rods and cones receives message, the message is spread through the synaptic terminals of vision neurons. Everything that can be seen by one eye is that eye’s visual field. Because our eyes are located anteriorly in the head, the visual field of the two eyes overlap considerably. We have binocular vision due to the large region where the visual fields of the two eyes overlap. The visual field of each eye is divided into two regions. Moreover, visual information from the right half of each visual field is conveyed to the left side of the brain, where as visual information from the left half of each visual field is conveyed to the right side of the brain.

(ref: http://www.arn.org/docs/glicksman/120104%20fig3.jpg)

  1. Axons of all retinal ganglion cells in one eye exit the eyeball at the optic disc and form the optic nerve on that side.
  2. At the optic chiasm, axons from the temporal half of each retinal do not cross but continue directly to the thalamus on the same side.
  3. In contrast, axons from the nasal half of each retina cross and continue to the opposite thalamus.
  4. Axon branches of the retinal ganglion cells project to the mid brain, where they participate in circuits that govern constrictions of pupils in response to light and co-ordination of head and eye movements. Hypothalamus also establishes the patterns of sleep and other activities that occur on a daily schedule in response to intervals of light and darkness.
  5. The axons of thalamic neurons form the optic radiation as they project from the thalamus to the primary visual area of the cortex on the same side.

(ref: http://www.thebrainwiki.com/uploads/Forebrain/thalamus.jpg)


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Being a part of the cerebrum, They are located at the edges of the brain. Each temporal lobe deals with auditory processing and semantics of speech and vision. The temporal lobe hosts the hippocampus and is therefore involved in the formation of memories. Their function include Emotional Responses, Hearing, Memory and Speech.


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How do we see? (Part1: The Eye)

In some ways the eye is like a camera: Its optical elements focus an image of some object on a light-sensitive “film – the retina – while ensuring the correct amount of light to make the proper “exposure”.

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When your eyelids are open, light enters your eye through a circular hole called the pupil and is focussed by a lens onto the light sensitive retina attached to the back of the eye.

The size of the pupil can be adjusted to allow more light to enter when the environment is dim, and less light when it’s bright.   There are about 126 million sensory cells in the retina, both cone-shaped cells which are color-sensitive and rod-shaped cells which aren’t color-sensitive but can detect low levels of light, useful for night vision.

Most cameras work in the same way as the eye – when the shutter is open, light enters a roughly circular hole called theaperture and is focussed by a lens onto a light sensitive medium at the back of the camera, either film or an electronic sensor.   Some types of camera, like a pinhole camera, don’t have a lens, and some digital cameras don’t have a shutter; nevertheless, understanding how these things work will help make your photographs better. (ref: Flying Kiwi)


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To understand how the eye forms clear images of objects on the retina, we must examine three processes:

  1. The refraction (bending) of light by the lens and cornea
  2. The change in shape of the lens
  3. Narrowing of the pupil

More information about vision – http://www.accessexcellence.org/AE/AEC/CC/vision_background.php

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Brains learns to see

When light rays traveling through a transparent substance pass into a second transparent substance with a different density, they bend at the junction between the two. This bending is called refraction. As light rays enter the eye, they are refracted at the anterior and posterior surface of the cornea. Both surfaces of the lens of the eye further refract the light rays so they come into exact focus on the retina. Images focused on the retina are inverted; they are upside down. The reason the world does not look inverted and reversed is that the brain “learns” early in life to co-ordinate visual images with the orientations of objects. The brain stores the inverted and reversed images we acquired when we first reached for and touched objects and interprets those visual images as being correctly oriented in space.

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Physiology of Vision: Photoreceptors and photopigments

The first step in visual transduction is absorption of light by a photopigment, a colored protein that undergoes structural changes when it absorbs light. The single type of photopigment in rods is rhodopsin. Three different cone photopigments are present in the retina, one in each of three types of cones. Colour vision results from different colors of light selectively activating the different cone photopigments.  All photopigments associated with vision contain two parts: retinal and opsin. Different opsins permit the rods and cones to absorb different colours (wavelength) of incoming light. Rhodopsins absorbe blue to green light(colour) most effectively, where as the three different cone photopigments most effectively absorb blue, green, or yellow-orange light(and colour).


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Sound

Sound is a form of energy. Being able to hear sound is one of our most important senses. Some of the sounds you hear are loud and some are soft. This is the intensity of the sound. Sounds can also be high or low. This is the pitch of the sound.

Sounds are made by something moving backwards and forwards. This is called vibrating. When you speak, vocal cords in your throat vibrate. When you play a guitar the strings vibrate to produce the sound.

Sound waves travel through the air. The air particles squash up and move apart! Sound can even travel through liquids and gases because the particles pass on the vibrations. Sounds travel fastest through solids, and slowest through gases.

  • Sound travels in all directions.
  • Sound travels in waves.

how the amplitude and frequency affects sound waves

  • Sound is made from vibrations.
  • Sound can be reflected, we call this an echo.
  • Sounds get louder as they closer and then fainter as they get further away.
  • Sounds travel to our ears.

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To learn about sounds in underwater visit http://www.divediscover.whoi.edu/expedition12/hottopics/sound.html