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Archive for Μαΐου 2015

Noting (✎) and Plotting (✍)

31/05/2015 Σχολιάστε

https://enrichingmysoul.files.wordpress.com/2015/05/b35e75a4b26613f2415ee2a19182fd7e.jpg

Writing, like reading, has the power to travels us!

 

https://enrichingmysoul.wordpress.com/

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Κατηγορίες:λογοτεχνία Ετικέτες:

Λήθη

31/05/2015 Σχολιάστε

Mαβίλης Λορέντζος

Καλότυχοι οἱ νεκροὶ ποὺ λησμονᾶνε

Τὴν πίκρια τῆς ζωῆς. Ὄντας βυθήση

Ὁ ἥλιος καὶ τὸ σούρουπο ἀκλουθήση,

Μὴν τοὺς κλαῖς, ὁ καϋμός σου ὅσος καὶ νάναι.

Τέτοιαν ὥρα οἱ ψυχὲς διψοῦν καὶ πᾶνε

Στῆς λησμονιᾶς τὴν κρουσταλλένια βρύση·

Μὰ βοῦρκος τὸ νεράκι θὰ μαυρίση,

Ἄ στάξη γι’ αὐτὲς δάκρυ ὅθε ἀγαπᾶνε.

Κι’ ἂν πιοῦν θολὸ νερὸ ξαναθυμοῦνται,

Διαβαίνοντας λιβάδια ἀπὸ ἀσφοδῆλι,

Πόνους παλιούς, ποὺ μέσα τους κοιμοῦνται.–

Ἄ δὲ μπορῆς παρὰ νὰ κλαῖς τὸ δείλι,

Τοὺς ζωντανοὺς τὰ μάτια σου ἂς θρηνήσουν:

Θέλουν – μὰ δὲ βολεῖ νὰ λησμονήσουν.

Μάης 1896

 

http://www.ekebi.gr/dam/poems.aspx?tmp=1&item=279

Κατηγορίες:ποιήματα Ετικέτες: ,

Έχουν σχέση τα λουλούδια με τον έρωτα;

30/05/2015 Σχολιάστε

Leonid Afremov

 

"Flowers are the sweetest things God ever made, and forgot to put a soul into." ~ H. Beecher

 

 

Του Νίκου Τσούλια

      Τα λουλούδια έχουν σχέση με τον έρωτα. Έχουν σχέση συμβολική αλλά και ουσιαστική. Έχουν σχέση βιολογική / φυσική αλλά και πολιτισμική. Έχουν σχέση διαχρονική και συστατική / ιδρυτική. Έχουν σχέση μέσω του ανθρώπου. Και στον άνθρωπο αποκτούν τα λουλούδια και ο έρωτας το μεγαλείο τους˙ εδώ κατακτά και η σχέση τους την απόλυτη ομορφιά, γιατί εδώ ιεροποιούνται και αποθεώνονται στον κόσμο του πνεύματος και της ελευθερίας.

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Κατηγορίες:πολιτισμός Ετικέτες: , , ,

Μίλτος Σαχτούρης: Τα τραύματα της Ιστορίας

30/05/2015 Σχολιάστε

 

Μίλτος Σαχτούρης: Τα τραύματα της Ιστορίας

Ο Σαχτούρης σε σκίτσο του Αλέκου Φασιανού, από την ηρωική εποχή του Καφέ Μπραζίλιαν

Η έκδοση των απάντων του ποιητή φέρνει στο προσκήνιο τα υπαρξιακά και κοινωνικά χάσματα της μεταπολεμικής εποχής. Αφιέρωμα

ΤΟ ΒΗΜΑ, 26/10/2014

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ΘΕΜΑΤΑ ΚΑΙ ΑΠΑΝΤΗΣΕΙΣ ΠΑΝΕΛΛΑΔΙΚΩΝ ΕΞΕΤΑΣΕΩΝ: Φυσική, Ιστορία (κατευθύνσεις)

29/05/2015 Σχολιάστε

Άσκηση γραφής, τρόπος ζωής

29/05/2015 Σχολιάστε

An ostraka (pottery sherd) which served as a ballot in voting to ostracize (banish) the statesman Aristides.
Copyright: Thomas Sakoulas, Ancient-Greece.org

“Whenever Hellenes take anything from non-Hellenes, they eventually carry it to a higher perfection.”
Plato, Epinomis

Του Νίκου Τσούλια

 

      Αν η δυνατότητα της ομιλίας είναι το πρώτο βήμα του μικρού παιδιού για να αυτοδιαμορφώσει το «είδωλο του ανθρώπου», το διάβασμα και το γράψιμο είναι το επόμενο άλμα της πνευματικότητάς του με το οποίο προσδιορίζεται οριστικά και αμετάκλητα από τη δυνατότητά του για να κατακτήσει την ανεξαρτησία του πνεύματός του.

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Πόσο ίσοι είμαστε

29/05/2015 Σχολιάστε

Viviano Codazzi, Arch of Constantine, Rome

 

Ο Πιερ Ροζανβαλόν αφηγείται την ιστορία της ισότητας από τα τέλη του 18ου αιώνα

Βιστωνίτης Α., ΤΟ ΒΗΜΑ, 2/11/2014

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Συνδικαλισμός και αριστερισμός

28/05/2015 Σχολιάστε

Abstract Art Painting by Mirza Zuplijanin

Mirza Zupljanin

 

Η περίπτωση της δευτεροβάθμιας εκπαίδευσης

Του Νίκου Τσούλια

      Με δεδομένο ότι πάντα υπήρχε ένας έντονος πολιτικός ριζοσπαστισμός στη δευτεροβάθμια εκπαίδευση διαμορφώθηκε εύκολα ένα ευνοϊκό υπόστρωμα για την ανάπτυξη αριστερών ρευμάτων και κατ’ επέκταση αντίστοιχων αριστερίστικων παραταξιακών σχημάτων. Σε περιόδους δε περιοριστικών οικονομικών πολιτικών – όπως στη σημερινή συγκυρία των μνημονιακών κυβερνητικών πολιτικών – τα σχήματα αυτά ευνοούνται έστω και παροδικά, όχι γιατί δίνουν κάποια προοπτική αλλά γιατί εκφράζουν πιο εύκολα τους αγανακτισμένους!

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Ebola and the Vast Viral Universe

28/05/2015 Σχολιάστε

 

Advances in microscopy have allowed scientists like Sriram Subramaniam and colleagues at the National Cancer Institute to look at the workings of tiny viruses. In this case, microscopy was used to illustrate the complex process in which human cells infected with HIV-1, green and blue, are linked to uninfected cells.CreditIllustration by Donald Bliss/N.I.H, from The Journal of Virology/American Society for Microbiology

By NATALIE ANGIER, The New York Times, 27.10.2014

Behind the hellish Ebola epidemic ravaging West Africa lies an agent that fittingly embodies the mad contradictions of a nightmare. It is alive yet dead, simple yet complex, mindless yet prophetic, seemingly able to anticipate our every move.

For scientists who study the evolution and behavior of viruses, the Ebola pathogen is performing true to its vast, ancient and staggeringly diverse kind. By all evidence, researchers say, viruses have been parasitizing living cells since the first cells arose on earth nearly four billion years ago.

Some researchers go so far as to suggest that viruses predate their hosts. That they essentially invented cells as a reliable and renewable resource they could then exploit for the sake of making new viral particles.

It was the primordial viral “collective,” said Luis P. Villarreal, former director of the Center for Virus Research at the University of California, Irvine, “that originated the capacity for life to be self-sustaining.”

“Viruses are not just these threatening or annoying parasitic agents,” he added. “They’re the creative front of biology, where things get figured out, and they always have been.”

Researchers are deeply impressed by the depth and breadth of the viral universe, or virome. Viruses have managed to infiltrate the cells of every life form known to science. They infect animals, plants, bacteria, slime mold, even larger viruses. They replicate in their host cells so prodigiously and stream out into their surroundings so continuously that if you collected all the viral flotsam afloat in the world’s oceans, the combined tonnage would outweigh that of all the blue whales.

Not that viruses want to float freely. As so-called obligate parasites entirely dependent on host cells to replicate their tiny genomes and fabricate their protein packages newborn viruses, or virions, must find their way to fresh hosts or they will quickly fall apart, especially when exposed to sun, air or salt.

“Drying out is a death knell for viral particles,” said Lynn W. Enquist, a virologist at Princeton.

How long shed virions can persist if kept moist and unbuffeted — for example, in soil or in body excretions like blood or vomit — is not always clear but may be up to a week or two. That is why the sheets and clothing of Ebola patients must be treated as hazardous waste and surfaces hosed down with bleach.

Viruses are masters at making their way from host to host and cell to cell, using every possible channel. Whenever biologists discover a new way that body cells communicate with one another, sure enough, there’s a virus already tapping into exactly that circuit in its search for new meat.

GRAPHIC

Treating Ebola: The Hunt for a Drug

Although there are currently no drugs or vaccines approved in the United States to treat or prevent Ebola, health officials have used several experimental drugs in the recent epidemic.

OPEN GRAPHIC

Reporting recently in Proceedings of the National Academy of Sciences, Karla Kirkegaard, a professor of microbiology and genetics at Stanford University School of Medicine, and her colleagues described a kind of “unconventional secretion” pathway based on so-called autophagy, or self-eating, in which cells digest small parts of themselves and release the pieces into their surroundings as signaling molecules targeted at other cells — telling them, for example, that it’s time for a new round of tissue growth.

The researchers determined that the poliovirus can exploit the autophagy conduit to cunning effect. Whereas it was long believed that new polioparticles could exit their natal cell only by bursting it open and then seeking new cells to infect, the researchers found that the virions could piggyback to freedom along the autophagy pathway.

In that way, the virus could expand its infectious empire without destroying perfectly good viral factories en route. The researchers suspect that other so-called naked or nonenveloped viruses (like the cold virus and theenteroviruses that have lately plagued children in this country and Asia) could likewise spread through unconventional secretion pathways.

For their part, viruses like Ebola have figured out how to slip in and out of cells without kicking up a fuss by cloaking themselves in a layer of greasylipids stolen from the host cell membrane, rather as you might foist a pill down a pet’s throat by smearing it in butter.

According to Eric O. Freed, the head of the virus-cell interaction section at the National Cancer Institute, several recent technological breakthroughs have revolutionized the study of viruses.

Advances in electron microscopy and super-resolved fluorescence microscopy — the subject of this year’s Nobel Prize in Chemistry — allow scientists to track the movement of viral particles in and between cells, and to explore the fine atomic structure of a virus embraced by an antibody, or a virus clasped onto the protein lock of a cell.

Through ultrafast gene sequencing and targeted gene silencing techniques, researchers have identified genes critical to viral infection and drug resistance. “We’ve discovered viruses we didn’t even know existed,” Dr. Freed said. And that could prove important to detecting the emergence of a new lethal strain.

Gene sequencing has also allowed researchers to trace the deep background of viruses, which, at an average of a few billionths of an inch across, are far too minuscule to fossilize. In fact, viruses were first identified in the 19th century by size, as infectious agents able to pass through filters that trapped all bacteria.

Through genomic analysis, researchers have identified ancient viral codes embedded in the DNA of virtually every phyletic lineage. The unmistakable mark of a viral code? Instructions for making the capsid, the virus’s protective protein shell, which surrounds its genetic core and lends the viral particle its infectious power.

MORE EBOLA COVERAGE

“It turns out there are not many ways to make the pieces that will snap together into an effective package,” said Dr. Enquist, of Princeton. “It’s an event that may have occurred only once or twice” in evolutionary history.

Viruses are also notable for what they lack. They have no ribosomes, the cellular components that fabricate the proteins that do all the work of keeping cells alive.

Instead, viruses carry instructions for co-opting the ribosomes of their host, and repurposing them to the job of churning out capsid and other viral proteins. Other host components are enlisted to help copy the instructions for building new viruses, in the form of DNA or RNA, and to install those concise nucleic texts in the newly constructed capsids.

“Viruses are almost miraculously devious,” Dr. Freed said. “They’re just bundles of protein and nucleic acid, and they’re able to get into cells and run the show.”

“On the one hand, they’re quite simple,” Dr. Enquist said. “On the other hand, they may be the most highly evolved form of genetic information on the planet.”

Viruses also work tirelessly to evade the immune system that seeks to destroy them. One of the deadliest features of the Ebola virus is its capacity to cripple the body’s first line of defense against a new pathogen, by blocking the release of interferon.

“That gives the virus a big advantage to grow and spread,” said Christopher F. Basler, a professor of microbiology at Mount Sinai School of Medicine.

At the same time, said Aftab Ansari of Emory University School of Medicine, the virus disables the body’s coagulation system, leading to uncontrolled bleeding. By the time the body can rally its second line of defense, the adaptive immune system, it is often too late.

Yet the real lethality of Ebola, Dr. Ansari said, stems from a case of mistaken location, a zoonotic jump from wild animal to human being. The normal host for Ebola virus is the fruit bat, in which the virus replicates at a moderate pace without killing or noticeably sickening the bat.

“A perfect parasite is able to replicate and not kill its host,” Dr. Ansari said. “The Ebola virus is the perfect parasite for a bat.”

Correction: October 28, 2014

An earlier version of this article referred incorrectly to the position Luis P. Villarreal holds at the Center for Virus Research at the University of California, Irvine. He is a professor at the center and its founding director, but he is not the current director. A picture credit with an earlier version of this article mistated part of the name of an organization. It is the American Society for — not of — Microbiology

 

 

 

 

 

 

 

 

Κατηγορίες:βιολογία Ετικέτες: , , , ,

ΘΕΜΑΤΑ ΚΑΙ ΑΠΑΝΤΗΣΕΙΣ ΠΑΝΕΛΛΑΔΙΚΩΝ ΕΞΕΤΑΣΕΩΝ: Λατινικά, Χημεία, Ηλεκτρολογία και Ανάπτυξη Εφαρμογών σε Προγραμματιστικό Περιβάλλον

27/05/2015 Σχολιάστε

This revolutionary moment

27/05/2015 Σχολιάστε

 

Paris Boulevard- Robert Henri

 

Index looks into the future of journalism; Transit keeps alive the memory of the Maidan; in Syn og Segn, climate optimist Kristin Halvorsen calls for a global price tag on pollution; Kulturos barai talks to urban ecologist Warren Karlenzig; Rigas Laiks congratulates Reykjavik’s first anarchist mayor;Merkur discusses photography and the definition of artistic value; La Revue nouvelle braces itself for more European political deadlock; Kritiikki profiles Russian émigré author Sergei Dovlatov; and Nova Istra remembers the Croatian émigré poet Viktor Vida.

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Κατηγορίες:κοινωνία

«Ζούμε σ’ ένα matrix…η ανατροπή είναι ζήτημα χρόνου»

27/05/2015 Σχολιάστε
manosdanezis2
Μάνος Δανέζης
Συνέντευξη: Μαριάνθη Πελεβάνη -  04/05/2014

 

Επίκουρος καθηγητής Αστροφυσικής, στο Πανεπιστήμιο Αθηνών. Έχει δημοσιεύσει δεκάδες άρθρα στον Τύπο, εκατοντάδες επιστημονικές εργασίες, διαθέτει ένα πλούσιο συγγραφικό έργο βιβλίων Φυσικής, Αστροφυσικής Ιστορίας και Φιλοσοφίας των Θετικών Επιστημών αλλά και κοινωνικού ενδιαφέροντος. Τα τελευταία χρόνια οι ρηξικέλευθες απόψεις του γίνανε γνωστότερες από τις τηλεοπτικές σειρές «Το Σύμπαν που αγάπησα» και «Έτσι βλέπω τον κόσμο» στην ΕΤ3, όπου υπήρξε (μαζί με τον Δρ Ε. Θεοδοσίου) παρουσιαστής και επιστημονικός υπεύθυνος. Παρακολουθώντας τον, δεν ξέρω να σας πω αν είναι «ταπεινο-εκκεντρικός», «φευγάτος», ή και υπερ-ευφυής ως επιστήμονας αλλά σίγουρα βαδίζει στον δικό του ρυθμό, προσπαθώντας να μας αλλάξει τον τρόπο που βλέπουμε τον κόσμο. Ο λόγος για τον Μάνο Δανέζη.

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