Monday, August 26, 2013

CT Scan vs MRI

CT Scan (or CAT Scan) and an MRI operate differently and are better suited for different types of diagnoses. An MRI suited for examining soft tissue, (e.g. ligament and tendon injury, spinal cord injury, brain tumors etc.) while a CT scan is better suited for bone injuries, lung and chest imaging, and detecting cancers. CT scans are widely used in emergency rooms because the procedure takes less than 5 minutes. An MRI, on the other hand, can take up to 30 minutes.
An MRI typically costs more than a CT scan. One advantage of an MRI is that it does not use radiation while CAT scans do. This radiation is harmful if there is repeated exposure.

Comparison chart</> EMBED THIS CHART

Improve this chartCT ScanCT ScanMRIMRI
Cost:CT Scan costs range from $1,200 to $3,200; they usually cost less than MRIs (about half the price of MRI).MRI costs range from $1200 to $4000 (with contrast); which is usually more than CT scans and X-rays, and most examining methods.
Time taken for complete scan:Usually completed within 5 minutes. Actual scan time usually less than 30 seconds. Therefore, CT is less sensitive to patient movement than MRI.Scanning typically run for about 30 minutes.
Radiation exposure:The effective radiation dose from CT ranges from 2 to 10 mSv, which is about the same as the average person receives from backgroundradiation in 3 to 5 years. Usually, CT is not recommended for pregnant women or children unless absolutely necessary.None. MRI machine control/limit energy deposition in patient
Ability to change the imaging plane without movingthe patient:With capability of MDCT, isotropic imaging is possible. After helical scan with Multiplanar Reformation function, an operator can construct any plane.MRI machines can produce images in any plane. Plus, 3D isotropic imaging also can also produce Multiplanar Reformation.
Effects on the body:Despite being small, CT can pose the risk of irradiation. Painless, noninvasive.No biological hazards have been reported with the use of the MRI.
Scope of application:CT can outline bone inside the body very accurately.MRI is more versatile than the X-Ray and is used to examine a large variety of medical conditions.
Application:Suited for bone injuries, Lung and Chest imaging, cancer detection. Widely used in Emergency Room patient.Suited for Soft tissue evaluation, e.g. ligament and tendon injury, spinal cord injury, brain tumors etc.
Details of bony structures:Provides good details about bony structuresLess detailed compared to X-ray
Acronym for:Computed (Axial) TomographyMagnetic Resonance Imaging
Details of soft tissues:A major advantage of CT is that it is able to image bone, soft tissue and blood vessels all at the same time.Much higher soft tissue detail as compare to CT scan.
Principle used for imaging:Uses X-rays for imagingUses large external field, RF pulse and 3 different gradient fields
History:The first commercially viable CT scanner was invented by Sir Godfrey Hounsfield in Hayes, United Kingdom; the first patient brain-scan was done on 1 October 1971.First commercial MRI in 1981, with significant increase in MRI resolution and choice of imaging sequences over time.
Principle:X-ray attenuation was detected by detector & DAS system, follow by math. model (back projection model) to calculate the value of pixelism then become a image.Body tissue that contains hydrogen atoms (e.g. in water) is made to emit a radio signal which is detected by the scanner. Search for "magnetic resonance" for physics details.
Image specifics:Good soft tissue differentiation especially with intravenous contrast. Higher imaging resolution and less motion artifact due to fast imaging speed.Demonstrates subtle differences between the different kinds of soft tissues.
Limitation for Scanning patients:Patients with any Metal implants can get CT scan. A person who is very large (e.g. over 450 lb) may not fit into the opening of a conventional CT scanner or may be over the weight limit for the moving table.Patients with Cardiac Pacemakers,tattoos and metal implants are contraindicated due to possible injury to patient or image distortion (artifact). Patient over 350 lb maybe over table weight limit. Any ferromagnetic object may cause trauma/burns.
Intravenous Contrast Agent:Non-ionic iodinated agent is covalently bind the iodine and have fewer side effects. Allergic reaction is rare but more common than MRI contrast. Risk of contrast induced nephropathy (especially in renal insufficiency(GFR<60 class="IL_AD" id="IL_AD8" nbsp="" span="" style="background-attachment: scroll !important; background-color: transparent !important; background-image: none !important; background-position: 0% 50%; background-repeat: repeat repeat !important; border-bottom-color: rgb(0, 153, 0) !important; border-bottom-style: dotted !important; border-bottom-width: 1px !important; color: rgb(0, 153, 0) !important; cursor: pointer !important; display: inline !important; float: none !important; padding: 0px 0px 1px !important; position: static;">diabetes
 & dehydratio
Very rare allergic reaction. Risk of nephrogenic systemic fibrosis with free Gadolinium in the blood and severe renal failure. It is contraindicated in patients with GFR under 60 and especially under 30 ml/min.


Image:MRI-Knee-Example.jpg

How the scans work


EDITHow MRIs work

Using a very powerful magnet and pulsing radio waves the detection coils in the MRI scanner read the energyproduced by water molecules as they re-align themselves after each RF alignment pulse. The collected data is reconstructed into a two-dimensional illustration through any axis of the body. Bones are virtually void of water and therefore do not generate any image data. This leaves a black area in the images. MRI scanners are best suited for imaging soft tissue.
The CT scan of a person's torso.
The CT scan of a person's torso.

EDITHow a CT Scan works

CT, Computerized Axial Tomography, uses xrays to generate images of the body, including bone. In the CT scanner the x-ray tube, (source) rotates around the patient laying on the table. On the opposite side of the patient from the tube is the x-ray detector. This detector recieves the beam that makes it through the patient. The beam is sampled via some 764 channels, (approximate number of channels). The signal received by each channel is digitized to a 16 bit value and sent to the reconstruction processor. Measurements are taken about 1000 times per second. Scan rotations are usually 1 to 2 seconds long. Each view/channel chunk of scan data is compared to calibration scan data of air, water and polyethelyne, (soft plastic) previously acquired in the exact same relative location. The comparisons allow the image pixels to have a known value for a particular substance in the body regardless of differences in patient size and exposure factors. The more samples, or views, the better the picture.
The following video explains how the different types of scans work — Ultrasound, CT scan, MRI and PET scan.

EDITPros and Cons

In the following ABC News video, Paul Christo, M.D. at Johns Hopkins explains the use of MRI or CT scans for diagnosing problems related to the spine.

EDITAdvantages of MRI over CAT Scan

  • A CAT scan uses X rays to build up a picture. MRI uses a magnetic field to do the same and has no known side effects related to radiation exposure.
  • MRI has much higher detail in the soft tissues.
  • One of the greatest advantages of MRI is the ability to change the contrast of the images. Small changes in the radio waves and the magnetic fields can completely change the contrast of the image. Different contrast settings will highlight different types of tissue
  • Another advantage of MRI is the ability to change the imaging plane without moving the patient. Most MRI machines can produce images in any plane.
  • Contrast agents are also used in MRI but they are not made of iodine. There are fewer documented cases of reactions to MRI contrast and it is considered to be safer than X-ray dye.
  • For purposes of tumor detection and identification, MRI is generally superior. However, CT usually is more widely available, faster, much less expensive, and may be less likely to require the person to be sedated or anesthetized.
  • CT may be enhanced by use of contrast agents containing elements of a higher atomic number than the surrounding flesh (iodine, barium). Contrast agents for MRI are those which have paramagnetic properties. One example is gadolinium. Iodine use may be associated with allergic reactions.

EDITAdvantages of CT Scan over MRI

  • CT is very good for imaging bone structures.
  • Some patients who have received certain types of surgical clips, metallic fragments, cardiac monitors or pacemakers cannot receive an MRI.
  • The time taken for total testing is shorter than taken by MRI
  • MRI cannot be done in patients who are claustrophobic as the patient has to remain inside the noisy machine for about 20-45 minutes
  • It is cheaper than an MRI. A CT scan costs $1,200 to $3,200 while an MRI can cost up to $4,000.

EDITCost of Machines

Not surprisingly, there are various CT scanners available and there is a large variation in price depending upon the features and brand. This is a good pricing guide for CT scan machines. A vanilla 4-slice CT scanner costs $85,000 to $150,000. A 16-slice scanner costs $145,000 to $225,000 and the top-of-the-line 64-slice CTs can cost up to $450,000. The machines also typically need annual maintenance, which can also cost tens of thousands of dollars.
MRI machines are available in 1.5 T and 3 T (T stands for Tesla) models. 3T models are more expensive but offer higher image quality and shorter scanning times. 1.5 T MRI scanners start at around $1 million and 3T models are 50% more expensive. Manufacturers may include accessories in their quote, which include a workstation to view images, contrast injectors, This is a good guide for MRI scanners.

Cat5e vs Cat6

Cat6 cables, also called Category 6 or Cat6 cables, provide lower crosstalk, a higher signal-to-noise ratio, and are suitable for 10GBASE-T (10-Gigabit Ethernet), while Cat5e cables support only up to 1000BASE-T (Gigabit Ethernet). As a means of future-proofing your network, Cat6 is generally a better choice and worth the small premium in price. Cat5e and Cat6 cables are both backwards compatible, which means newer Cat6 cables can be used with older Cat5e, Cat5 and even Cat3 equipment.



Wiring

Both Cat5e and Cat6 are twisted pair cables that use copper wires, typically 4 twisted pairs in each cable. The specification for Cat6 features more stringent specifications for crosstalk and system noise, and provides performance of up to 250 MHz. Cat5e, in contrast, performs up to 100 MHz. This was often achieved using a spline (a longitudinal separator) in the wiring, which isolates each of the four pairs of twisted wire. However, this made Cat6cables more rigid; newer cables use other methods to reduce noise and are more flexible. Regardless of whether a spline is used, a cable that meets Cat6 specifications provides significantly lower interference or near end crosstalk (NEXT) in the transmission. It also improves equal level far end crosstalk (ELFEXT), return loss and insertion loss compared with Cat5e. The result is less noise, fewer errors and higher data rates in the transmission of the signal.

Your computer uses these to talk to other computers - network Cat5e and Cat6 cables




How to identify

The category is almost always printed on ethernet cables. It is not possible to identify cable categories by color, butCat6 cables are often thicker than Cat5e because it uses thicker copper wires.


EDITMaximum Length

Both Cat5e and Cat6 cable specifications allow lengths up to 100 meters, but Cat6e has a lower max length (55 meters) when used for 10GBASE-T (10 Gigabit Ethernet). In order to run 10GBASE-T for 100 meters, Category 6acable, or Augmented Category 6, cables need to be used. Cat6a cables allow performance up to 500 MHz.
If network infrastructure requires covering distances larger than 100 meters, repeaters or switches are required to amplify the signal.

EDITSpeed

As mentioned previously, Cat6 cables can be used to power 10GBASE-T, or 10 Gigabit Ethernet, while the maximum that Cat5e cables can support is 1GBASE-T, or 1 Gigabit Ethernet. This is because Cat6 cables performup to 250 MHz, more than twice that of Cat5e cables (100 MHz).

EDITCost

The price of ethernet cables vary by length, manufacturer and seller. In general, Cat6 cables are 10-20% more expensive compared with Cat5e cables. However, cables are generally cheap and the speed boost offered by Cat6 cables usually makes the price premium well worth it, even for home use.

EDITWhat and where to buy


Cat5e cables seem to be more popular on Amazon.com. Only 2 of the top 20 best selling ethernet cables on Amazon are Cat6.



reference
http://www.diffen.com/difference/Cat5e_vs_Cat6

Sunday, August 25, 2013

The Alien Files





On April 8, 2011 the FBI unveiled the Vault, declassifying decades of top secret government documents for the first time.
These documents cover topics that have plagued conspiracy theorists for the past decades. The files also contain thousands of reports of UFO sightings and alien activity. The Alien Files and The Conspiracy Files will uncover the truth of these secrect documents and offer a first hand look on the mysteries of the universe.
Unsealed Files will launch in the Fall. Check your local listings.

About the Show: Alien Files

Unsealed: Alien Files investigates recently released documents regarding alien and UFO encounters, made accessible to the public in 2011 by the Freedom of Information Act. Each week, Unsealed: Alien Files tackles one compelling alien case by opening these previously off-limits secret files. Based on the newly discovered information the show re-examines key evidence and follows developing leads.
Unsealed: Alien Files investigates mass UFO sightings, personal abductions, government cover-ups and breaking alien news from around the world. We delve into the "photoshopping" of space, the value of Wikileaks, and the role social media plays in alien stories. Finally, we examine these newly released documents to see how alien visitations may have affected our past, and what influence they may have on our future. This show will have believers wanting more and skeptics questioning their long held beliefs. Unsealed: Alien Files ... exposing the biggest secret on planet Earth.

How a Sea Squirt Could Help You Grow New Limbs



By COLUMN by LEE DYE | ABC News
The closest relative we humans have in the huge population of invertebrates that blanket the earth is a tiny, inconspicuous flower-like marine critter that is amazing in its abilities to regenerate its damaged tissue from its blood vessels alone.
Scientists believe this odd character, just one of many spineless animals known as "sea squirts," or "tunicates," may hold the genetic secrets that might eventually allow humans to regrow a lost arm, or accept a heart from someone else without danger of rejection.
But, alas, if this unpretentious little animal is going to be our medical salvation, we may have to accept its dark side. It can also foul our beaches and our boats, and smother crabs and oysters while killing off much native wildlife. And it feels right at home in a heavily polluted harbor.
Botryllus schlosseri, commonly known as the golden star, perhaps because it is frequently golden in color and looks kind of like a star, or a flower, or a blob, may be a bit player in the world of animals without a backbone, which make up 95 percent of the species in the animal world. But it could have a huge future in the world of medicine.
It is believed to have been the first invertebrate to have a vasculature heart system, similar to that in humans, with blood cells traveling through blood vessels. But astonishingly, it can regrow everything just with its blood vessels.
"The whole body can regenerate from the vasculature alone, the heart, digestive system, sophisticated tissues," Ayelet Voskoboynik of Stanford University's Stem Cell Institute said in releasing a study. "And it can do this relatively fast, probably using stem cells."
Voskoboynik and an international team of scientists have just sequenced the genome of Botryllus schlosseri, which we shall henceforth just call the "star." The hope is that once scientists understand how the genes operate in the star, they will be able to come up with new treatments for a wide range of human diseases.
The star has only 580 million base pairs of DNA, compared to 3 billion base pairs in humans, but there is a surprising amount of common ground. The researchers found that 77 percent of human genes were also present in the star.
"We found genes that are critical to the development and function of the vertebrate heart, and eye, and the ability to hear," they report in their study, published in the journal eLIFE. "Mutations in these genes are implicated in a variety of human diseases and disorders, including heart diseases, cataracts, and deafness."
There is reason to believe the star may hold the genetic secrets that have plagued cardiac patients who have received a new heart only to have it rejected by their own body.
The star forms colonies comprised of individuals that form clusters in various patterns, star-like, flowers, or opals. But amazingly, when one colony meets another, it can either merge with the other, gradually becoming one, or both can remain separate, suggesting the animal knows how to accept or reject another set of organs. It would be good to know exactly what that is.
Although usually orange to yellow in color, it can also be red, black, green, or an assortment of colors, and it can form many different shapes, depending on which solid substance the colony latches onto, frequently the bottom of a boat, or a piece of valuable marine gear in near-shore areas. And that's where the conflict comes in.
Colonies can join together to form large mats that cover everything from rocks to boat hulls to other marine organisms, frequently killing native plants and animals. It is very invasive, as demonstrated by its rapid growth along both North American coasts.
The star is believed to be a native of Europe that somehow made its way to the East Coast a few decades ago, probably by clinging to the hull of a ship. In the mid 1940s it was discovered in San Francisco Bay and has since been found from Baja California to British Columbia.
But while it may be a nuisance to some, it seems destined to be a hero to others. That role was foreseen by Charles Darwin in the mid 1800s.
Darwin thought these odd but fascinating creatures might help us understand how life evolved to include vertebrates, like us.
That doesn't seem all that far out, now that we know we share so many genes with a distant relative most of us never knew we had.

Par colonne par LEE DYE | ABC Nouvelles
Les nous, les humains ont plus proche parent dans l'immense population d'invertébrés qui recouvrent la terre est une petite créature marine , discret comme une fleur qui est étonnant dans sa capacité à régénérer son tissu endommagé de ses vaisseaux sanguins seul.
Les scientifiques croient que ce personnage étrange , juste l'un des nombreux animaux invertébrés connus sous le nom " ascidies " ou " tuniciers , " peut détenir les secrets génétiques qui pourraient éventuellement permettre aux humains de repousser un bras perdu , ou accepter d'un cœur de quelqu'un d'autre sans danger de rejet .
Mais, hélas, si ce petit animal sans prétention va être notre salut médical, nous pourrions avoir à accepter son côté sombre . Il peut également encrasser nos plages et nos bateaux , et étouffer les crabes et les huîtres tout en tuant beaucoup de faune indigène . Et il se sent à l'aise dans un port fortement pollué .
Botryllus schlosseri , communément connu comme l'étoile d'or , peut-être parce qu'il est souvent de couleur dorée et ressemble un peu à une étoile ou une fleur, ou un blob , peut-être un petit joueur dans le monde des animaux sans colonne vertébrale , ce qui rend jusqu'à 95 pour cent des espèces dans le monde animal. Mais il pourrait avoir un grand avenir dans le monde de la médecine.
Il est soupçonné d'avoir été le premier invertébré d'avoir un système cardiaque vasculaire , semblable à celle des humains , avec des globules voyageant à travers les vaisseaux sanguins. Mais étonnamment , il peut repousser tout simplement avec ses vaisseaux sanguins.
" Le corps tout entier peut se régénérer à partir de la vascularisation seul, le cœur , le système digestif , les tissus sophistiqués », Ayelet Voskoboynik de Institut des cellules souches de l'Université de Stanford a déclaré en libérant une étude. " Et il peut le faire assez rapidement , probablement en utilisant des cellules souches. "
Voskoboynik et une équipe internationale de scientifiques viennent séquencé le génome de Botryllus schlosseri , que nous allons désormais il suffit d'appeler la «star». L'espoir est qu'une fois que les scientifiques à comprendre comment les gènes fonctionnent dans l'étoile, ils seront en mesure de trouver de nouveaux traitements pour un large éventail de maladies humaines.
La star a seulement 580 millions de paires de bases d'ADN , contre 3 milliards de paires de bases chez l'homme, mais il ya une quantité surprenante de terrain d'entente. Les chercheurs ont constaté que 77 pour cent des gènes humains étaient également présents dans l'étoile .
" Nous avons trouvé des gènes qui sont essentiels pour le développement et la fonction du cœur des vertébrés , et des yeux, et la capacité à entendre », ils signalent dans leur étude , publiée dans la revue ELIFE . " Les mutations dans ces gènes sont impliqués dans une variété de maladies et de troubles humains, y compris les maladies cardiaques , les cataractes et la surdité . "
Il ya des raisons de croire que l'étoile peut détenir les secrets génétiques qui ont frappé les patients cardiaques qui ont reçu un nouveau cœur seul à avoir rejeté leur propre corps.
La star forme des colonies composées d' individus qui forment des grappes dans divers modèles , ressemblant à des étoiles , des fleurs ou opales . Mais étonnamment , quand on rencontre une autre colonie , il peut soit fusionner avec l'autre , devenant peu à peu un, ou les deux peut rester séparés , ce qui suggère que l'animal sait comment accepter ou de rejeter un autre ensemble d'organes . Il serait bon de savoir exactement ce que c'est.
Bien que généralement de couleur orange à jaune , il peut également être rouge, noir, vert, ou un assortiment de couleurs , et il peut former de nombreuses formes différentes , selon la substance solide de la colonie s'accroche , souvent au fond d'un bateau, ou une pièce d'équipement marin précieux dans les zones littorales . Et c'est là que le conflit entre en jeu.
Les colonies peuvent se regrouper pour former de grands tapis qui couvrent tout, depuis les rochers de coques de bateaux à d'autres organismes marins , tuant fréquemment les plantes et les animaux indigènes . Il est très envahissante , comme en témoigne sa croissance rapide sur les deux côtes nord-américaines.
La star est considéré comme originaire de l'Europe qui en quelque sorte fait son chemin vers la côte Est il ya quelques décennies , probablement en s'accrochant à la coque d'un navire. Au milieu des années 1940, il a été découvert dans la baie de San Francisco et a depuis été trouvé de Basse-Californie à la Colombie- Britannique.
Mais tout cela peut être une nuisance pour certains, il semble destiné à devenir un héros pour les autres. Ce rôle est dévolu par Charles Darwin dans le milieu des années 1800.
Darwin pensait ces créatures étranges mais fascinantes pourraient nous aider à comprendre comment la vie a évolué pour inclure les vertébrés, comme nous.

Cela ne semble pas si loin , maintenant que nous savons que nous partageons tant de gènes avec un parent éloigné plupart d'entre nous ne savions que nous avions .

Por COLUMNA DYE por LEE | ABC News
Los seres humanos tienen parientes más cercanos en la enorme población de invertebrados que cubren la tierra es una pequeña criatura marina poco visible , como una flor que es increíble en su capacidad para regenerar el tejido dañado de los vasos sanguíneos en paz.
Los científicos creen que este personaje raro, sólo uno de muchos animales invertebrados conocidos como " ascidias ," o " tunicados , " puede contener los secretos genéticos que eventualmente podría permitir a los humanos a regenerar un brazo perdido , o aceptar un corazón de otra persona sin el peligro de rechazo .
Pero , por desgracia , si este animalito sin pretensiones va a ser nuestra salvación médica , es posible que tengamos que aceptar su lado oscuro. También puede ensuciar nuestras playas y nuestros barcos , y sofocar los cangrejos y ostras , mientras que matar a mucha fauna nativa. Y se siente como en casa en un puerto muy contaminado .
Botryllus schlosseri , comúnmente conocida como la estrella de oro, tal vez porque a menudo es de color dorado y se ve un poco como una estrella o una flor, o una mancha , puede ser un actor en el mundo de los animales sin columna vertebral , lo que hace el 95 por ciento de las especies del mundo animal. Sin embargo, podría tener un gran futuro en el mundo de la medicina.
Se cree que ha sido la primera invertebrado tener un sistema vasculatura del corazón , similar a la de los seres humanos , con células de la sangre que viajan a través de vasos sanguíneos . Pero, sorprendentemente , se puede regenerar todo sólo con sus vasos sanguíneos.
"Todo el cuerpo puede regenerarse a partir de la vasculatura solo, el corazón, el aparato digestivo, los tejidos sofisticados" Ayelet Voskoboynik del Instituto de Células Madre de la Universidad de Stanford , dijo en la liberación de un estudio. " Y puede hacerlo con relativa rapidez , probablemente con células madre . "
Voskoboynik y un equipo internacional de científicos ha secuenciado el genoma acaba de Botryllus schlosseri , que vamos a partir de ahora sólo llamar la "estrella ". La esperanza es que una vez que los científicos a comprender cómo los genes funcionan de la estrella, que será capaz de llegar a nuevos tratamientos para una amplia gama de enfermedades humanas.
La estrella tiene sólo 580 millones de pares de bases de ADN , en comparación con 3 mil millones de pares de bases en los seres humanos , pero hay una sorprendente cantidad de terreno común . Los investigadores encontraron que el 77 por ciento de los genes humanos , también estuvieron presentes en la estrella.
"Hemos encontrado genes que son críticos para el desarrollo y la función del corazón de vertebrados , y los ojos, y la capacidad de escuchar ", según informan en su estudio, publicado en la revista eLIFE . " Las mutaciones en estos genes están implicados en una variedad de enfermedades y trastornos humanos , incluyendo enfermedades del corazón , cataratas, y la sordera . "
Hay razones para creer que la estrella puede contener los secretos genéticos que han afectado a los pacientes cardíacos que han recibido un nuevo corazón, sólo para que se rechazado por su propio cuerpo.
La estrella forma colonias compuestas de individuos que forman agrupaciones en diversos patrones , como estrellas , flores, o ópalos . Pero, sorprendentemente , cuando una colonia se encuentra con otra , se puede ya sea fundirse con el otro , convirtiéndose gradualmente en uno , o ambos pueden permanecer separados , lo que sugiere que el animal sabe cómo aceptar o rechazar otro conjunto de órganos . Sería bueno saber exactamente lo que es.
Aunque generalmente de color naranja a amarillo en color, sino que también puede ser de color rojo , negro, verde , o un surtido de colores , y puede formar muchas formas diferentes , dependiendo de qué sustancia sólida se enganche en la colonia , con frecuencia la parte inferior de un barco , o una pieza de equipo marino valiosa en las áreas cercanas a la costa . Y ahí es donde entra en juego el conflicto
Las colonias pueden unirse para formar grandes alfombras que cubren todo, desde las rocas para cascos de barcos a otros organismos marinos , matando con frecuencia las plantas y animales nativos. Es muy invasiva , como se demuestra por su rápido crecimiento a lo largo de ambas costas de América del Norte .
La estrella se cree que es originario de Europa que de alguna manera se abrió camino a la costa este hace algunas décadas , probablemente por el apego al casco de un barco. A mediados de 1940 se descubrió en la Bahía de San Francisco y desde entonces ha sido encontrado desde Baja California hasta la Columbia Británica .
Pero si bien puede ser una molestia para algunos, parece destinado a ser un héroe para otros. Ese papel fue previsto por Charles Darwin a mediados de 1800 .
Darwin pensaba que estas criaturas extrañas pero fascinante podrían ayudarnos a entender cómo la vida evolucionó para incluir a los vertebrados , como nosotros.

Eso no parece tan lejos , ahora que sabemos que compartimos muchos genes con un pariente lejano la mayoría de nosotros no sabíamos que teníamos 

Nach Spalte von LEE DYE | ABC News
Die nächsten Verwandten wir Menschen haben in der riesigen Bevölkerung von Wirbellosen, die Erde ist eine winzige , unscheinbare Blume-wie marine Lebewesen, das erstaunlich ist, in seine Fähigkeiten , seine geschädigte Gewebe aus seiner Blutgefäße allein regenerieren Decke.
Wissenschaftler glauben, dass diese seltsame Zeichen , nur eine von vielen Tieren als Rückgrat " Seescheiden " oder bekannten " Seescheiden , " halten kann , die genetischen Geheimnisse , die schließlich Menschen erlauben , einen verlorenen Arm nachwachsen kann oder akzeptieren ein Herz von jemand anderem ohne Gefahr Ablehnung.
Aber, ach , wenn diese unprätentiöse Tierchen wird unsere medizinische Rettung sein kann , müssen wir seine dunkle Seite zu akzeptieren. Es kann auch zu einer Verschmutzung unsere Strände und unsere Boote und ersticken Krabben und Austern während Abtötung viel einheimische Tierwelt . Und es fühlt sich wie zu Hause in einem stark verschmutzten Hafen.
Botryllus schlosseri , die gemeinhin als dem goldenen Stern bekannt , vielleicht weil sie häufig in goldene Farbe und sieht irgendwie aus wie ein Stern oder eine Blume oder ein Blob , vielleicht ein wenig Spieler in die Welt der Tiere ohne Rückgrat , was machen bis 95 Prozent der Arten in der Tierwelt. Aber es könnte eine große Zukunft in der Welt der Medizin .
Es wird angenommen, dass die ersten wirbellosen ein Herz Gefäßsystem System, ähnlich wie beim Menschen , mit Blutzellen Reisen durch die Blutgefäße zu haben. Aber erstaunlich , kann das alles nur mit seinen Blutgefäßen nachwachsen .
" Der ganze Körper kann aus dem Gefäßsystem alleine regenerieren , das Herz, Verdauungssystem , ausgefeilte Gewebe ", Ayelet Voskoboynik von der Stanford University Stem Cell Institute sagte bei der Freigabe eine Studie . "Und es können dies tun, relativ schnell, wahrscheinlich mit Stammzellen . "
Voskoboynik und ein internationales Team von Wissenschaftlern hat das Genom nur Botryllus schlosseri , die wir fortan nur nennen die sequenziert "Stern". Die Hoffnung ist, dass, sobald die Wissenschaftler zu verstehen, wie die Gene in den Stern zu betreiben , werden sie in der Lage sein , sich mit neuen Behandlungen für ein breites Spektrum von Krankheiten beim Menschen .
Der Stern hat nur 580 Millionen Basenpaare der DNA , im Vergleich zu 3 Milliarden Basenpaare in den Menschen , aber es gibt eine überraschende Menge von Gemeinsamkeiten . Die Forscher fanden heraus , dass 77 Prozent der menschlichen Gene waren auch in der Stern.
"Wir fanden Gene, die entscheidend für die Entwicklung und Funktion des Wirbeltier- Herz und Auge und die Fähigkeit zu hören sind", berichten sie in ihrer Studie , veröffentlicht in der Zeitschrift eLife . " Mutationen in diesen Genen sind in einer Vielzahl von menschlichen Krankheiten und Störungen , einschließlich Herzerkrankungen , Katarakte, und Taubheit beteiligt sind. "
Es gibt Grund zu glauben, dass die Sterne können die genetischen Geheimnisse, die Herzpatienten , die ein neues Herz erhalten haben , nur um sie , von ihren eigenen Körper geplagt haben zu halten.
Der Stern bildet Kolonien von Individuen, die Cluster in verschiedenen Mustern , star -like , Blumen oder Opale bilden zusammen. Aber erstaunlich , wenn man eine andere Kolonie trifft , kann es entweder mit dem anderen zu verschmelzen , allmählich eine oder beide können getrennt bleiben , was das Tier weiß, wie man annehmen oder ablehnen eine weitere Reihe von Organen. Es wäre gut, genau zu wissen, was das ist.
Obwohl in der Regel orange bis gelb in der Farbe , kann es auch rot, schwarz , grün, oder ein Sortiment von Farben, und es kann in vielen verschiedenen Formen zu bilden, je nachdem, welche feste Substanz die Kolonie klinkt , häufig der Boden eines Bootes oder ein Stück wertvolle marine Gang in Nearshore- Regionen . Und das ist, wo der Konflikt kommt in.
Kolonien können sich zusammenschließen, um große Matten , die alles von Felsen Bootskörper auf andere marine Organismen decken zu bilden, häufig töten einheimische Pflanzen und Tiere . Es ist sehr invasiv, wie durch sein schnelles Wachstum auf beiden nordamerikanischen Küsten demonstriert.
Der Stern wird angenommen, dass eine native of Europe , der irgendwie seinen Weg an die Ostküste vor ein paar Jahrzehnten , wahrscheinlich durch Festhalten an der Rumpf eines Schiffes sein . In der Mitte der 1940er Jahre wurde es in San Francisco Bay entdeckt und ist seitdem von Baja California bis British Columbia gefunden.
Aber während es ein Ärgernis für einige sein mag, so scheint es, dazu bestimmt, ein Held für andere zu sein . Diese Rolle wurde von Charles Darwin in der Mitte der 1800er vorgesehen.
Darwin dachte, diese seltsame, aber faszinierende Geschöpfe könnten uns helfen zu verstehen , wie das Leben an Wirbeltieren beinhalten , wie uns entwickelt.

Dass nicht alle so weit scheinen out , jetzt, da wir wissen, dass wir gemeinsam so viele Gene mit einem entfernten Verwandten die meisten von uns nie wusste, wir hatten.