Ott túl a rácson. Fotó: Németh József. In: Németh József: Leica felvételek. Athenaeum, Budapest, 1944.
Over the lattice. Photo: Jozsef Nemeth. 1944.
Milky way over Stakes by Álvaro Pérez Alonso y Jose Manuel Pérez Alonso
Source: Flickr / zeissmicro
In research published in Nature Cell Biology, scientists from the EMBL Australia research team based at Monash University’s Australian Regenerative Medicine Institute (ARMI) have revealed new insights into how cells organise and form an early mammalian embryo.
In an early mammalian embryo, just 8-cells large, the roundish cells do something they had never done before – something that would determine whether the embryo survived or failed. They change their shape. The cells become elongated and compacted against each other, before returning to their rounded shape and dividing again and again.
When compaction does not occur, embryos tend not to survive. And the timing of compaction has been linked to success in IVF (in vitro fertilisation) treatments. But how did these young, seemingly featureless cells undertake this vital shaping process?
Researchers Dr Nicolas Plachta, Dr Juan Carlos Fierro-González and Dr Melanie White have found a new mechanism controlling the process. The team used live imaging technology and microinjected fluorescent markers to capture the action in vivid images and video.
"Our images reveal arm-like structures called filopodia appearing on the outer membrane of some cells during the 8-cell stage, and it is these filopodia that are responsible for contorting cell shape, and forming the embryo’s first tissue-like layers,” Dr Fierro-González said.
"For the first time, we have been able to watch as filopodia reach out and grab neighbouring cells, pulling them closer and elongating the cell membranes. We think that this enables the cells to effectively compact, as their new non-rounded shape makes the most of the available space." But the role of filopodia was made clearer upon seeing what happened next.
"We then saw the filopodia retract as they released their grip on neighbouring cells, allowing them to return to a somewhat rounded shape before they continued on their journey of cell division," Dr Fierro-González said.
Dr Plachta and his team observed that cell division never occurred while filopodia were extended over the cells, but only once the filopodia had retracted. These observations have lead the researchers to believe that the filopodia provide the necessary surface tension to allow the cells to undergo expansion and compaction.
Photographer Robert Frank in the home of Wayne Miller while shooting for his book “The Americans.”
Next Stop, Saturn
"Taken on a road leading to the town of Hankie which is the source of light pollution in the distance behind the treeline. Saturn is most prominent in the sky." -Andrew Kennard
Lawn courts, Temple, London, 1962.
Thanks to undr
Unknowingly Making History — The First Ever “Selfie” (1839)On November 19, 2013, the Oxford Dictionaries announced their word of the year for 2013 to be “selfie”, which they define as “a photograph that one has taken of oneself, typically one taken with a smartphone or webcam and uploaded to a social media website.”Although it’s current rampant incarnation is quite recent, the “selfie” is far from being a strictly modern phenomenon. Indeed, the photographic self-portrait is surprisingly common in the very early days of photography exploration and invention, when it was often more convenient for the experimenting photographer to act as model as well.In fact, the picture shown above is considered by many to be the first photographic portrait ever taken was a “selfie”. The image in question was taken in 1839 by an amateur chemist and photography enthusiast from Philadelphia named Robert Cornelius. Cornelius had set his camera up at the back of the family store in Philadelphia. He took the image by removing the lens cap and then running into frame where he sat for a minute before covering up the lens again. On the back he wrote “The first light Picture ever taken. 1839.”
I really like his hair.
James Jowers (America, 1938-2009) Coney Island, 1966, gelatin silver print, gift of the photographer, © George Eastman House
James Jowers interest in photography began while serving in the United States Army where he was trained in darkroom procedures. In 1965 he became a student at the New School and studied under Lisette Model, who later became a close friend and mentor. At this time he was living on the Lower East Side and worked as a night porter at St. Luke’s Hospital; leaving him free to explore the City during the day and photograph life as he encountered it on the streets. Model later introduced Jowers to the Nancy Palmer Photo Agency where he was represented for several years.
The photography collection at George Eastman House holds approx. 400 James Jowers prints. The majority of the images were shot in New York City in the 1960s and early 1970s, an important and interesting time in US history. The photographs are of the New York City street photography genre. There are some remarkable images in this collection, including portraits of New Yorkers in various settings and anti-war protests in Central Park and elsewhere. There are also approximately 25 photographs of New Orleans in the 1970s.
Page 1 of 75