paragraph_text: Delia Arnold (born 26 January 1986 in Kuala Lumpur) is a professional squash player who represented Malaysia. She currently lives in Selangor and was coached by Ahmed Malik and Peter Genever. She reached a career-high world ranking of World No. 12 in September 2015 after beating World Number 2, Raneem El Weleily in the quarter finals of the British Open.

paragraph_text: William Neil Scanlon (born November 13, 1956) is a former tennis player from the United States, who won seven singles and two doubles titles during his 13-year professional career. The right-hander reached his career-high ATP singles ranking of World No. 9 in January 1984. He is also known for upsetting top-seeded John McEnroe in the fourth round at the 1983 US Open.

paragraph_text: Step coenzyme yield ATP yield Source of ATP Glycolysis preparatory phase − 2 Phosphorylation of glucose and fructose 6 - phosphate uses two ATP from the cytoplasm. Glycolysis pay - off phase Substrate - level phosphorylation 2 NADH 3 or 5 Oxidative phosphorylation: Each NADH produces net 1.5 ATP (instead of usual 2.5) due to NADH transport over the mitochondrial membrane Oxidative decarboxylation of pyruvate 2 NADH 5 Oxidative phosphorylation Krebs cycle Substrate - level phosphorylation 6 NADH 15 Oxidative phosphorylation 2 FADH Oxidative phosphorylation Total yield 30 or 32 ATP From the complete oxidation of one glucose molecule to carbon dioxide and oxidation of all the reduced coenzymes.

paragraph_text: Since 1973, 26 men have been ranked No. 1 by the ATP, of which 17 have been year - end No. 1. The current world number one is Roger Federer.

paragraph_text: ATP synthase is an enzyme that creates the energy storage molecule adenosine triphosphate (ATP). ATP is the most commonly used ``energy currency ''of cells for most organisms. It is formed from adenosine diphosphate (ADP) and inorganic phosphate (P). The overall reaction catalyzed by ATP synthase is:

paragraph_text: ATP synthase is the enzyme that makes ATP by chemiosmosis. It allows protons to pass through the membrane and uses the free energy difference to phosphorylate adenosine diphosphate (ADP), making ATP. The generation of ATP by chemiosmosis occurs in mitochondria and chloroplasts, as well as in most bacteria and archaea, an electron transport chain pumps H+ ions in the thylakoid spaces through thylakoid membranes. The energy from the electron movement through electron transport chains cross through ATP synthase which allows the proton to pass through them and use this free energy difference to photophosphorylate ADP making ATP.

paragraph_text: The 1994 Marseille Open was an ATP tennis tournament played on indoor carpet and held in Marseille, France from 31 January through 6 February 1994. It was the second edition of the tournament and it was part of the ATP World Series. Fourth-seeded Marc Rosset won the singles title.

paragraph_text: Since 1973, 26 men have been ranked number 1 by the ATP, of which 17 have been year - end number 1. The current world number one is Rafael Nadal.

paragraph_text: In respiring bacteria under physiological conditions, ATP synthase, in general, runs in the opposite direction, creating ATP while using the proton motive force created by the electron transport chain as a source of energy. The overall process of creating energy in this fashion is termed oxidative phosphorylation. The same process takes place in the mitochondria, where ATP synthase is located in the inner mitochondrial membrane and the F - part projects into mitochondrial matrix. The consumption of ATP by ATP - synthase pumps proton cations into the matrix.

paragraph_text: The 2010 Serbia Open (also known as "Serbia Open powered by Telekom Srbija" for sponsorship reasons) was a tennis tournament played on outdoor clay courts. It was the 2nd edition of the event. It was part of the ATP World Tour 250 series of the 2010 ATP World Tour. It took place at the Milan Gale Muškatirović complex in Belgrade, Serbia, from May 3 through May 9, 2010.

paragraph_text: The 2013 Madrid Open (also known as the Mutua Madrid Open for sponsorship reasons) was a professional tennis tournament played on outdoor clay courts at the Park Manzanares in Madrid, Spain from 6–12 May. It was the 12th edition of the event on the ATP World Tour and 5th on the WTA Tour. It was classified as an ATP World Tour Masters 1000 event on the 2013 ATP World Tour and a Premier Mandatory event on the 2013 WTA Tour.

paragraph_text: The Djokovic -- Federer rivalry is a tennis rivalry between two professional tennis players, Novak Djokovic and Roger Federer. They have faced each other 45 times with Djokovic leading 23 -- 22. This includes a record 15 Grand Slam matches, four of which were finals, plus a record ten semifinals. Both players have beaten the other in each of the four Grand Slam tournaments. Federer dominated during their early slam matches, but Djokovic now has a 9 -- 6 lead in Grand Slam matches, including eight wins in the last ten meetings. A notable aspect of the rivalry is their ability to beat each other on any given day, including Grand Slam play, making it one of the most competitive and evenly matched rivalries in the Open Era. To date Federer is the only man to have beaten Djokovic in all four majors, and likewise Djokovic is the only man to have beaten Federer in all four majors. Both men accomplished this after having beaten each other at Wimbledon. Both players are generally considered to be the two greatest hard court players in the open era.

paragraph_text: The 2005 China Open was an ATP International Series and WTA Tour Tier II tennis tournament held in Beijing, China.

paragraph_text: Jan Hájek (born 7 August 1983) is a retired male professional tennis player from the Czech Republic. He reached the third round of the 2007 French Open and attained a career-high ATP singles ranking of World No. 71 in November 2006.

paragraph_text: The main role of chloroplasts is to conduct photosynthesis, where the photosynthetic pigment chlorophyll captures the energy from sunlight and converts it and stores it in the energy - storage molecules ATP and NADPH while freeing oxygen from water. They then use the ATP and NADPH to make organic molecules from carbon dioxide in a process known as the Calvin cycle. Chloroplasts carry out a number of other functions, including fatty acid synthesis, much amino acid synthesis, and the immune response in plants. The number of chloroplasts per cell varies from one, in unicellular algae, up to 100 in plants like Arabidopsis and wheat.

paragraph_text: ``Royals ''was serviced as Lorde's debut single in mid-2013, becoming an international crossover hit and made her the youngest solo artist to achieve a US number - one single on the Billboard Hot 100 since 1987. Lorde's debut studio album Pure Heroine (2013) garnered positive reviews for her depiction of suburban adolescence; yielding the additional top - ten single`` Team'', it topped the national charts in New Zealand and Australia and reached number three on the US Billboard 200. The following year, Lorde curated the soundtrack for The Hunger Games: Mockingjay -- Part 1 (2014) and provided its lead single, ``Yellow Flicker Beat ''. Lorde released her second studio album Melodrama (2017) after a three - year hiatus, launched with`` Green Light'' as its lead single. The album debuted at number one in New Zealand and Australia, as well as topping the US Billboard 200. She served as an executive producer alongside Jack Antonoff. The record deals with themes of heartbreak and solitude.

paragraph_text: Djokovic is widely regarded as one of the greatest tennis players of all time. He has won 13 Grand Slam singles titles, five ATP Finals titles, 30 Masters 1000 series titles, 12 ATP World Tour 500 tournaments, and has held the No. 1 spot in the ATP rankings for a total of 223 weeks. In majors, he has won six Australian Open titles, four Wimbledon titles, two US Open titles and one French Open title. In 2016, he became the eighth player in history to achieve the Career Grand Slam. Following his victory at the 2016 French Open, he became the third man to hold all four major titles at once, the first since Rod Laver in 1969, and the first ever to do so on three different surfaces.

paragraph_text: Lleyton Hewitt is both the youngest world No. 1 (20 years, 268 days) and youngest year - end No. 1, while Rafael Nadal is the oldest year - end No. 1 (31 years, 211 days). Roger Federer is the oldest No. 1 (36 years, 314 days).

paragraph_text: The New York City Subway is a rapid transit system owned by the City of New York and leased to the New York City Transit Authority, a subsidiary agency of the state - run Metropolitan Transportation Authority (MTA). Opened in 1904, the New York City Subway is one of the world's oldest public transit systems, one of the world's most used metro systems, and the metro system with the most stations. It offers service 24 hours per day on every day of the year, though some routes may operate only part - time.

paragraph_text: Telecommunications in India began with the introduction of the telegraph. The Indian postal and telecom sectors are one of the worlds oldest. In 1850, the first experimental electric telegraph line was started between Calcutta and Diamond Harbour. In 1851, it was opened for the use of the British East India Company. The Posts and Telegraphs department occupied a small corner of the Public Works Department, at that time.

Question: Who beat the oldest ATP world number one in the US Open?
Answer: Novak Djokovic