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Symmetric-key algorithm

Symmetric-key algorithms are algorithms for cryptography that use the same cryptographic keys for both encryption of plaintext and decryption of ciphertext. The keys may be identical or there may be a simple transformation to go between the two keys; the keys, in practice, represent a shared secret between two or more parties that can be used to maintain a private information link. This requirement that both parties have access to the secret key is one of the main drawbacks of symmetric key encryption, in comparison to public-key encryption. Symmetric-key encryption can use either stream ciphers or block ciphers. Stream ciphers encrypt letters of a message one at a time. An example is the Vigenère Cipher. Block ciphers take a number of bits and encrypt them as a single unit, padding the plaintext so that it is a multiple of the block size. Blocks of 64 bits were used; the Advanced Encryption Standard algorithm approved by NIST in December 2001, the GCM block cipher mode of operation use 128-bit blocks.

Examples of popular symmetric-key algorithms include Twofish, Serpent, AES, Blowfish, CAST5, Kuznyechik, RC4, DES, 3DES, Safer+/++, IDEA. Symmetric ciphers are used to achieve other cryptographic primitives than just encryption. Encrypting a message does not guarantee that this message is not changed while encrypted. Hence a message authentication code is added to a ciphertext to ensure that changes to the ciphertext will be noted by the receiver. Message authentication codes can be constructed from symmetric ciphers. However, symmetric ciphers cannot be used for non-repudiation purposes except by involving additional parties. See the ISO/IEC 13888-2 standard. Another application is to build hash functions from block ciphers. See one-way compression function for descriptions of several such methods. Many modern block ciphers are based on a construction proposed by Horst Feistel. Feistel's construction makes it possible to build invertible functions from other functions that are themselves not invertible.

Symmetric ciphers have been susceptible to known-plaintext attacks, chosen-plaintext attacks, differential cryptanalysis and linear cryptanalysis. Careful construction of the functions for each round can reduce the chances of a successful attack. Symmetric-key algorithms require both the sender and the recipient of a message to have the same secret key. All early cryptographic systems required one of those people to somehow receive a copy of that secret key over a physically secure channel. Nearly all modern cryptographic systems still use symmetric-key algorithms internally to encrypt the bulk of the messages, but they eliminate the need for a physically secure channel by using Diffie–Hellman key exchange or some other public-key protocol to securely come to agreement on a fresh new secret key for each message; when used with asymmetric ciphers for key transfer, pseudorandom key generators are nearly always used to generate the symmetric cipher session keys. However, lack of randomness in those generators or in their initialization vectors is disastrous and has led to cryptanalytic breaks in the past.

Therefore, it is essential that an implementation use a source of high entropy for its initialization. A reciprocal cipher is a cipher where, just as one enters the plaintext into the cryptography system to get the ciphertext, one could enter the ciphertext into the same place in the system to get the plaintext. A reciprocal cipher is sometimes referred as self-reciprocal cipher. Examples of reciprocal ciphers include: Atbash Beaufort cipher Enigma machine Purple cipher ROT13 XOR cipher Vatsyayana cipher

On Again... Off Again

"On Again... Off Again" was the Maltese entry in the Eurovision Song Contest 2004, performed in English by Julie & Ludwig. Composed by Philip Vella and with lyrics by Gerard James Borg, the song is a combination of dance music and opera. Julie begins by describing herself as "a girl of serious intention" and telling Ludwig that "I need some attention" over a dance beat. Ludwig's response, in which he describes her as "everything and nothing in one" is delivered in an operatic tenor style, he goes on to wonder. The second verse takes much the same form, with Julie pledging her love for Ludwig, who describes her as "the air, you're the love that I breathe" and "the magic that flows from within"; the duo sings the chorus in unison, describing their love as being "Like the rhythm of rain" and needing to "find an end to this game" of their mutual attraction. They describe the "wonderful times/Many natural highs". At the climax of the song, Ludwig sings a bridge begging Julie to "come across" the "river between us" in the name of love.

The chorus is sung again, this time slower and in an operatic style by Ludwig with Julie performing vocal embellishments to the lyric. The duo join in unison for the final chorus, which returns to the dance beat and varies the opening line to "Off again, on again", implying that they have resolved their differences; the song was autobiographical, as Julie and Ludwig were a couple in real life, whose relationship had been on and off. For their Eurovision appearance, Ludwig appeared dressed in a white shirt and black trousers, whilst Julie wore a striking pale pink gown; as Malta had not ended the 2003 contest in the top 11, the song was performed in the semi-final. Here, it was performed eighth, following Portugal's Sofia Vitória with "Foi magia" and preceding Monaco's Märyon with "Notre planète". At the close of voting, it had received 74 points, placing 8th in a field of 22 and qualifying Malta for the final. In the final, it was performed sixth, following Serbia and Montenegro's Željko Joksimović & Ad Hoc Orchestra with "Lane moje" and preceding the Netherlands' Re-Union with "Without You".

At the close of voting, it had received 50 points, placing 12th in a field of 24. Ordinarily, this would not have been enough to qualify for the next final, however both Spain and Germany placed in the top 10, thus allowing the 11th and 12th-place finishers to qualify automatically, it was succeeded as Maltese representative at the 2005 Contest by Chiara with "Angel". Diggiloo Thrush. "2004 Malta". Retrieved 2006-11-16

Forever Lulu (2000 film)

Forever Lulu is a 2000 American romantic comedy film directed by John Kaye starring Melanie Griffith, Penelope Ann Miller and Patrick Swayze. Ben and Lulu were one time college sweethearts who shared an intense passionate affair that circled around Lulu's untreated mental health condition, a condition which leads to her hospitalisation and their separation. Now Ben is a successful professional writer in a distant relationship with his wife Claire. Lulu leaves her treatment facility and seeks out a reluctant Ben to reveal that fifteen years ago they had a child whom she placed in adoption. Determined to meet him on his fifteenth birthday, Lulu asks Ben to join her on a cross country road trip to find their son. Bound at first by his need to protect Lulu from herself, Ben's uncertainty about the free-spirited Lulu is replaced with tender memories of their love affair and her vulnerable health; as they journey, Ben's current life is shared through Claire, who has flown out to intercept the pair.

Tensions between the three culminate with Claire telling Lulu about Ben and Claire's son who died the year before. A shaken Lulu calls to Ben, with Claire present, to open up about his son who died and the son they are about to meet. All three characters connect, in the process, Ben rediscovers his heart. Melanie Griffith - Lulu McAfee Penelope Ann Miller - Claire Clifton Patrick Swayze - Ben Clifton Joseph Gordon-Levitt - Martin Ellsworth Richard Schiff - Jerome Ellsworth Annie Corley - Millie Ellsworth Lee Garlington - Linda Davis Michael J. Pollard - Hippie Ryan Bollman - Freddie Forever Lulu on IMDb Forever Lulu at Rotten Tomatoes

Oleksandr Lukyanchenko

Oleksandr Oleksiyovych Lukyanchenko is the mayor of Donetsk city, in Ukraine. He was born to a Russian-speaking Ukrainian family in Donetsk Oblast, he attended primary school in the village of his birth, secondary school in Avdiivka. In 1962, he entered the Makiivka Civil Engineering Institute, served in a tank corps in the Soviet Army. After his service in the army, he worked as a chief engineer at multiple factories in Donetsk. After the collapse of the Soviet Union, he became vice-president of the city administration in Donetsk city on 27 November 1992. From 1994 to 1996, he worked in the Donetsk regional state administration, where he achieved the post of vice-president, he spent two years as the director-general of the highway administration of Donetsk Oblast. He was nominated vice-mayor of Donetsk city, under Volodymyr Rybak, who he replaced as mayor in 2002 after 31 March municipal elections, he was re-elected on 26 March 2006, again on 31 October 2010. His role came to prominence during the 2014 pro-Russian unrest in Ukraine.

Lukyanchenko has criticised separatists affiliated with the Donetsk People's Republic and the post-Euromaidan Ukrainian government. He said "Indeed, the seizure of administrative buildings is bad. Separatist slogans that were voiced in city squares are unacceptable, yet all these problems are a consequence of the new authorities' incorrect policy, their unwillingness to look into the problems to understand them". Lukyanchenko left the city of Donetsk for Kiev in early July, after he had received threats against his life from members of the Donetsk People's Republic, he said he would continue to run the city administration from Kiev until he was able to return to Donetsk. Autobiography on the Donetsk city website

Union for International Cancer Control

The Union for International Cancer Control or UICC is a membership based, non-governmental organization that exists to help the global health community accelerate the fight against cancer. Founded in 1933 and based in Geneva, Switzerland, UICC has a membership of over 800 organisations across 155 countries, features the world’s major cancer societies, ministries of health, research institutes and patient groups. UICC partners with its members, key partners, the World Health Organization, World Economic Forum and others, to tackle cancer on a global scale, their mission statement is: "To unite the cancer community to reduce the global cancer burden, to promote greater equity, to integrate cancer control into the world health and development agenda." Under the leadership of their Chief Executive Officer, Cary Adams, the Secretariat focuses on these three areas of priority: 1. Convening the global cancer control communityWorld Cancer Congress – held every two years; the Congress serves as a platform for discourse and advocacy as well as a learning and sharing opportunity for our members and partners around the world.

Global Roundtable Series, with key meetings scheduled for Latin America and Asia. World Cancer Leaders’ Summit is an annual high-level policy meeting dedicated to furthering global cancer control, it convenes key players from among UICC’s membership and network, health ministers and leaders of international businesses. World Cancer Day – UICC is working to promote 4 February as a World Cancer Day.2. Advocacy and putting cancer on the global health agendaTheir advocacy goals are: Press for cancer control to be included in the revised Millennium Development Goals in 2015. Encourage governments to fulfil their commitments from the UN High-level Meeting on NCDs, with a special focus on the importance of national cancer control plans and surveillance. Support WHO to develop robust systems for measuring progress against targets, ensuring governments can be held accountable.3. Coordinating high-impact global programmesUICC’s global programmes focus on five priority areas and target advocacy and training, as well as in-country activities in collaboration with partners and local UICC members.

GAPRI seeks to make essential pain medicines universally available. Providing direct support to more government ministries around the world, GAPRI aims to simplify the complicated international regulations around the distribution and use of morphine. CCI aims to advocate for cervical cancer to become a priority at the highest level, increase access to prevention and treatment services and develop crucial information on the cost of scaling up cervical cancer control activities. ChiCa – This programme seeks to ensure decision-makers around the world understand the importance of early treatment of cancer in children; the programme is developing resources to help governments in low- and middle- income countries, improve the way they respond to this issue. GETI facilitates the professional development of oncology healthcare workers and global leaders in cancer control. Through targeted fellowships and training the programme helps develop future leaders in cancer control and influence healthcare policy and practice across each of our priority programmes.

GICR aims to increase the number and quality of population-based cancer registries in low- and middle-income countries. Working in collaboration with the International Agency for Research on Cancer, UICC will roll- out hubs of excellence. In 1933, cancer researchers recognized a need to share knowledge and expertise globally, so founded UICC. Since UICC has grown into a respected forum for all professionals engaged in cancer prevention and control, its objective is to advance scientific and medical knowledge in research diagnosis and prevention of cancer and to promote all aspects of campaigns to prevent cancer throughout the world. Over the years, UICC has fostered the development of cancer institutions, the sharing and exchange of knowledge, the transfer of skills and technologies, the education of professionals engaged in cancer control; the UICC sponsors the biannual World Cancer Congress that brings together the world's leaders in the fight to control cancer. Leading clinicians, government agencies and NGO's, patient-care providers and advocates and behavioural scientists and public health experts focus on transforming the latest knowledge into strategies that countries, communities and individuals can employ to reduce the cancer burden.

The last World Cancer Congress, entitled "Strengthen. Inspire. Deliver.", took place in Kuala Lumpur, Malaysia in 2018. The congress was divided into five tracks: Motivating prevention and healthy behaviours Advances in screening and early detection Improved and sustainable healthcare systems for better outcomes Maximizing quality of life and death: empowering patients and care givers Raising funds and attracting resourcesThe next congress will take place in Muscat, Oman from 19–22 October 2020. UICC brings together a wide range of organisations, including voluntary cancer leagues and societies and treatment centres, public health authorities, patient support networks, advocacy groups, in some countries, ministries of health. UICC has cons

Nadia Yanowsky

Nadia Yanowsky is a Spanish ballet dancer. Yanowsky was raised in Las Palmas, Gran Canaria in the Canary Islands, she is the daughter of Russian ballet dancer Anatol Yanowsky and Spanish ballet dancer Carmen Robles, who both danced with the Lyon Opera Ballet. She is the sister of Lady Keenlyside, she began her ballet training at a school run by her parents and won a silver medal and audience prize at the Luxemburg International Ballet Competition. Yanowsky began her professional career in 2002 at the English National Ballet. In 2003 she was promoted to demi-soloist. In 2008 she moved to Amsterdam and joined the Dutch National Ballet as grand sujet, was promoted to the rank of soloist two years later. In 2018 she joined the Royal New Zealand Ballet and made her debut as the Sugar Plum Fairy in Val Caniparoli's The Nutcracker. Throughout her career Yanowsky has danced lead roles in many classical ballets including Romeo and Juliet, Carmen, Swan Lake, Paquita, La Bayadère, Les Sylphides, The Sleeping Beauty, The Nutcracker, Coppélia, The Rite of Spring and Le Corsaire, lead roles in Balanchine works including Serenade, Symphony in C, Concerto Barocco, Symphony in Three Movements and Violin Concerto.

Yanowsky has performed in works by William Forsythe, Hans Van Manen, Wayne McGregor, Christopher Wheeldon, John Neumeier, Maurice Bejart, Uwe Scholz, Angelin Preljocaj, Rudi van Dantzig, David Dawson