AMMAN (Reuters) - President Bashar al-Assad's forces pounded Sunni Muslim rebels in the city of Homs with artillery and from the air on Sunday, the second day of an offensive to expand loyalist control over Syria's strategic centre, activists said.
They said rebels defending the old centre of Homs and five adjacent Sunni districts had largely repelled a ground attack on Saturday by Assad's forces but reported fresh clashes and deaths within the city on Sunday.
The offensive follows steady military gains by Assad's forces, backed by Lebanese Hezbollah militants, in villages in Homs province and towns close to the Lebanese border.
British Foreign Secretary William Hague said Assad must halt his "brutal assault" on Homs. Gulf countries, which back the rebels, urged Lebanon to stop "parties" interfering in the Syria conflict, a reference to Iranian-backed Hezbollah.
Opposition sources and diplomats said the loyalist advance had tightened the siege of Homs and secured a main road link to Hezbollah strongholds in Lebanon and to army bases in Alawite-held territory near the Syrian coast, the main entry point for Russian arms that have given Assad a key advantage in firepower.
At least 100,000 people have been killed since the Syrian revolt against four decades of rule by Assad and his late father erupted in March 2011, making the uprising the bloodiest of the Arab Spring popular revolutions against entrenched autocrats.
The Syrian conflict is increasingly pitting Assad's Alawite minority, backed by Shi'ite Iran and its Hezbollah ally, against mainly Sunni rebel brigades supported by the Gulf states, Egypt, Turkey and others.
Sunni Jihadists, including al Qaeda fighters from Iraq, have also entered the fray.
ALARM
The loyalist advances have alarmed international supporters of the rebels, leading the United States to announce it will step up military support. Saudi Arabia has accelerated deliveries of sophisticated weaponry, Gulf sources say.
The Sham News Network opposition monitoring group said fighters belonging to the al Qaeda-linked Nusra Front had killed five loyalist troops in fighting in the Bab Hud district of Old Homs on Sunday.
Activists said one woman and a child had been killed in an airstrike on the old city, home to hundreds of civilians.
Video footage taken by the activists, which could not be immediately verified, showed the two bodies being carried in blankets as well as a man holding a wounded child with a huge gash in his head.
Rebel fighters also fought loyalist forces backed by tanks in the old covered market, which links the old city with Khalidiya, a district inhabited by members of tribes who have been at the forefront of the armed insurgency.
"After failing to make any significant advances yesterday, the regime is trying to sever the link between Khalidiya and the old city," Abu Bilal, one of the activists, said from Homs.
"We are seeing a sectarian attack on Homs par excellence, The army has taken a back role. Most of the attacking forces are comprised of Alawite militia being directed by Hezbollah."
The Alawites are an offshoot of Shi'ite Islam that have controlled Syria since the 1960s, when members of the sect took over the army and the security apparatus which underpin the power structure in the mainly Sunni country.
URBAN WARFARE
Located at a major highway intersection 140 kms (88 miles) north of Damascus, Homs is a majority Sunni city. But a large number of Alawites have moved into mostly new and segregated districts in recent decades, drawn by army and security jobs.
Lebanese security forces said Hezbollah appeared to be present in the rural areas surrounding Homs but there was no indication that it was fighting in the labyrinth streets of Homs, where it could take heavy casualties.
Anwar Abu al-Waleed, an activist, said rebel brigades were prepared to fight a long battle, unlike in Qusair and Tel Kalakh, two towns in rural Homs near the border with Lebanon that fell to loyalist forces in recent weeks.
"We are talking about serious urban warfare in Homs. We are not talking about scattered buildings in an isolated town but a large urban area that provides a lot of cover," he said.
Britain's Hague expressed concern over the escalation of fighting in Homs, saying in a statement: "I call upon the Assad regime to cease its brutal assault on Homs and to allow full humanitarian access to the country."
The Syrian conflict has aggravated neighboring Lebanon's own complex sectarian rivalry, triggering fighting between Alawite pro-Assad and Sunni anti-Assad militia in the northern city of Tripoli that has killed dozens.
Gulf foreign ministers meeting in Bahrain urged the Lebanese government to "commit to distancing itself from the Syrian crisis and to prevent any Lebanese parties from interfering in (Syria) in order to enable it to confront the brutal attacks and crimes conducted by the regime and its allies."
(Additional reporting by Angus McDowall and William Maclean in Dubai; Editing by Gareth Jones)
Auckland will put on VIP treatment for one of the first gay marriages in New Zealand - officials are even donating use of The Cloud for the reception.
A public vote will decide which of five couples will celebrate their wedding and reception in spectacular style.
The ZM radio station is billing it as "the most fabulous gay wedding ever", and will name one couple each day this week.
The winners of the public vote will be announced on July 26, and they will marry at 8am on the day the Marriage Amendment Act comes into effect, August 19.
And what a wedding it will be. The ceremony is at St Matthew in the City Anglican church. Traffic engineers will then give the couple VIP treatment, ensuring every traffic light is green for them as their horse and carriage makes its way to the waterfront for a reception at The Cloud on Queens Wharf.
Auckland Tourism, Events and Economic Development is giving the winning couple a surprise "Auckland Destination" package. Chief executive Brett O'Riley said the city was supporting same-sex marriage.
If Auckland wanted to be the most liveable city in the world, he said, it was important to embrace every aspect of a modern society.
However, Anglican Church hierarchy have not yet agreed to ministers celebrating same-sex marriages, so the couple will not be allowed to sign the wedding register in the church ceremony.
WASHINGTON (AP) ? The Obama administration on Friday warned Americans against all but essential travel to Egypt and moved to reduce the official U.S. presence in the country amid fears of widespread unrest.
Just hours after Egyptian officials said an American had been killed in clashes between government supporters and opponents in the city of Alexandria, the State Department said Americans should defer nonessential travel to Egypt, citing the uncertain security situation. It also said it would allow some nonessential staff and the families of personnel at the U.S. Embassy in Cairo to leave Egypt until conditions improve.
"Political unrest, which intensified prior to the constitutional referendum in December 2012 and the anniversary in 2013 of Egypt's 25th January Revolution, is likely to continue in the near future due to unrest focused on the first anniversary of the president's assumption of office," it said. "Demonstrations have, on occasion, degenerated into violent clashes between police and protesters, resulting in deaths, injuries and extensive property damage."
"Participants have thrown rocks and Molotov cocktails and security forces have used tear gas and other crowd control measures against demonstrators. There are numerous reports of the use of firearms as well," it said.
The department added that it had authorized the departure of "a limited number of nonemergency personnel" in addition to family members.
That move doesn't require anyone to depart but encourages them to go by allowing them to do so at government expense. Officials said dependents and nonessential staff could be ordered to leave if the situation deteriorates.
The U.S. is deeply concerned by developments in Egypt, where clashes have broken out ahead of planned mass protests against the government headed by Islamist President Mohammed Morsi. At least six Egyptians have been killed in days of clashes ahead of nationwide protests Sunday demanding Morsi's removal.
On Friday, an American was killed Alexandria while photographing battles between supporters and opponents of Morsi, according to security and medical officials.
The State Department's previous travel alert for Egypt, released on May 15, alerted Americans to the continuing possibility of political and social unrest. It urged them to keep abreast of local security conditions and exercise vigilance but did not warn them against any travel to the country.
June 28, 2013 ? NASA's Interface Region Imaging Spectrograph (IRIS) spacecraft launched Thursday at 7:27 p.m. PDT (10:27 p.m. EDT) from Vandenberg Air Force Base, Calif. The mission to study the solar atmosphere was placed in orbit by an Orbital Sciences Corporation Pegasus XL rocket.
"We are thrilled to add IRIS to the suite of NASA missions studying the sun," said John Grunsfeld, NASA's associate administrator for science in Washington. "IRIS will help scientists understand the mysterious and energetic interface between the surface and corona of the sun."
IRIS is a NASA Explorer Mission to observe how solar material moves, gathers energy and heats up as it travels through a little-understood region in the sun's lower atmosphere. This interface region between the sun's photosphere and corona powers its dynamic million-degree atmosphere and drives the solar wind. The interface region also is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate.
The Pegasus XL carrying IRIS was deployed from an Orbital L-1011 carrier aircraft over the Pacific Ocean at an altitude of 39,000 feet, off the central coast of California about 100 miles northwest of Vandenberg. The rocket placed IRIS into a sun-synchronous polar orbit that will allow it to make almost continuous solar observations during its two-year mission.
The L-1011 took off from Vandenberg at 6:30 p.m. PDT and flew to the drop point over the Pacific Ocean, where the aircraft released the Pegasus XL from beneath its belly. The first stage ignited five seconds later to carry IRIS into space. IRIS successfully separated from the third stage of the Pegasus rocket at 7:40 p.m. At 8:05 p.m., the IRIS team confirmed the spacecraft had successfully deployed its solar arrays, has power and has acquired the sun, indications that all systems are operating as expected.
"Congratulations to the entire team on the successful development and deployment of the IRIS mission," said IRIS project manager Gary Kushner of the Lockheed Martin Solar and Atmospheric Laboratory in Palo Alto, Calif. "Now that IRIS is in orbit, we can begin our 30-day engineering checkout followed by a 30-day science checkout and calibration period."
IRIS is expected to start science observations upon completion of its 60-day commissioning phase. During this phase the team will check image quality and perform calibrations and other tests to ensure a successful mission.
NASA's Explorer Program at Goddard Space Flight Center in Greenbelt, Md., provides overall management of the IRIS mission. The principal investigator institution is Lockheed Martin Space Systems Advanced Technology Center. NASA's Ames Research Center will perform ground commanding and flight operations and receive science data and spacecraft telemetry.
The Smithsonian Astrophysical Observatory designed the IRIS telescope. The Norwegian Space Centre and NASA's Near Earth Network provide the ground stations using antennas at Svalbard, Norway; Fairbanks, Alaska; McMurdo, Antarctica; and Wallops Island, Va. NASA's Launch Services Program at the agency's Kennedy Space Center in Florida is responsible for the launch service procurement, including managing the launch and countdown. Orbital Sciences Corporation provided the L-1011 aircraft and Pegasus XL launch system.
For more information about the IRIS mission, visit: http://www.nasa.gov/iris
Just in time for Wimbledon, Rolocule Games is releasing a new tennis game today. It’s not Rolocule’s first foray into virtual racquet sports, but it is the first that turns your iPhone into the controller and Apple TV into a gaming console. The Motion Tennis app, which costs $7.99, uses the iPhone’s gyroscope, magnetometer, and accelerometer to track the phone’s motion, so players can slice and slam shots across the court. All you need is an Apple TV and an iPhone: hook the two up, open the app, and you’re playing tennis. Rolocule is selling rolomotion ? its name for the technology that powers Motion Tennis ? on a few points, one being that it eliminates the necessity for a console system and lets people play on any Apple TV, anywhere. Rolocule will eventually be releasing Motion Badminton and Squash as well, and they’re working on a shooting game unofficially called “Die Zombies Die!” While Rolocule has only stepped into immediate competition with games like Wii Tennis today, it’s easy to see the implications of developing good console-free gaming. It’s a huge market to cut into, and rolomotion games are light, portable, and relatively cheap, excluding the $99 Apple TV. Rolocule raised an angel round in India last year with Mumbai Angels and Blume Ventures, though Gupta would not disclose how much they raised. He said that they might be looking to raise again, especially if they want to become leaders in this technology. I wouldn’t put it past them. It’s also a look into iPhone games that don’t involve tilting or swiping across the screen, which founder Rohit Gupta said has limited the creative breadth of games. That may be true, but it would seem that the first move for rolomotion would be to replicate every console game possible. Creativity can come after total game domination. Oh, and you might want to invest in one of those iPhone cases with an elastic strap on the back. You know, so you don’t end up ruining your TV and your phone. [Image from Rolocule]
WASHINGTON (AP) ? A Republican-led House committee is ready to try pressuring a central figure in the Internal Revenue Service investigation to shed light on the episode, five weeks after she sat before that same panel and refused to answer lawmakers' questions.
The planned vote Friday by the House Oversight and Government Reform Committee was aimed at Lois Lerner. She is a long-time IRS official whom agency executives put on administrative leave after she revealed that the IRS had singled out tea party groups seeking tax-exempt status for tough scrutiny.
Lerner was subpoenaed to testify to the Oversight Committee on May 22. When she appeared she said she had done nothing wrong, cited her constitutional right to not answer questions and left after a dramatic nine-minute standoff.
Lerner was a high-ranking IRS official in Washington who oversaw the agency's Cincinnati workers who screened applications for tax-exempt status. The IRS has apologized for imposing tough scrutiny on conservative groups who applied for that designation. It has since emerged that progressive groups also appeared on agency screening lists and that some suffered similar treatment.
Three congressional committees are investigating the IRS treatment of conservative groups, as is the Justice Department and the new leaders of the IRS itself. House Democrats are trying to expand the investigation to include how progressive groups were treated.
On Friday, the Oversight Committee was expected to approve a resolution along party lines stating that Lerner forfeited her right to remain silent by making opening remarks at last month's hearing.
Lerner's attorney, William W. Taylor, contested that theory in an email this week.
"Protesting your innocence and invoking right not to answer questions, which is what she did, is not a waiver. Legions of authority on our side," he wrote.
Taylor said in an email on Thursday that neither he nor Lerner would attend Friday's committee session.
House Oversight Chairman Darrell Issa, R-Calif., expressed hope that the vote would motivate Lerner to return to the committee. The vote could lead to a deal under which Lerner testifies with limited immunity, or to contempt charges if she continues to insist on her Fifth Amendment rights, said a GOP committee aide who spoke on condition of anonymity to discuss internal Republican thinking.
The resolution states that "a witness may not testify voluntarily about a subject and then invoke the privilege against self-incrimination when questioned about the details."
Several Republicans on the committee raised objections last month after Lerner invoked the Fifth Amendment.
Democrats said Issa rejected their request to allow legal experts with differing views on whether Lerner had waived her right not to respond to questions by giving testimony proclaiming her innocence.
On Thursday, the controversy moved in another direction as a clash escalated between the Treasury Department inspector general who investigated the IRS and congressional Democrats who called his probe of the agency misleading.
In a letter to lawmakers released Thursday, J. Russell George said his investigation found "progressives" was not among the inappropriate terms IRS screeners used to decide if groups merited close scrutiny for political work. Too much political activity can disqualify an applicant for a tax-exempt designation.
But George also wrote that "additional research" by his investigators found that of 298 applicants for tax-exempt status that the IRS flagged for possible political involvement between 2010 and 2012, six had "progress" or "progressive" in their names. Fourteen other cases with "progress" or "progressive" in the group's name were not sidetracked for additional examination, he wrote.
While 30 percent of such groups got special attention because of possible political work, every applicant for tax-exempt status with "tea party," ''patriots" or "9/12" in their names was set aside for screening, George said.
The term "progressives" did appear on some lists released earlier this week by House Democrats that also included "tea party" and that IRS workers used to watch for groups that might merit tough exams. But George's letter noted that "progressives" appeared on a different part of those lists and said that such groups were sent to different screeners from the ones who processed tea party applications.
Rep. Sander Levin of Michigan, top Democrat on the House Ways and Means Committee, said George should have revealed the appearance of progressive groups on the lists and the second set of screeners before now.
"The failure of the IG's audit to acknowledge these facts is a fundamental flaw in the foundation of the investigation and the public's perception of this issue," said Levin, using the abbreviation for inspector general.
We've seen loads of pop-up urbanism over the past few years, from parks to libraries, all designed to turn dead urban space into lively ones. But how do you stop people from immersing themselves in their phone screens in public? By building a larger screen, where they can be immersed together!
A group of designers in Auckland?who go by the name Oh No Sumo?installed this tiny theater on a street corner that they describe as a "hardscape," where "members of the public retreat individually into the media offered on their mobile phones." The timber-and-fabric tent is designed to counteract that innocuous behavior: YouTube videos and short films, playing on the screen from a projector above the entrence of the building, give people a reason to stop by and hang out.
Who chose the videos? The public, via the internet, of course. People could suggest videos and films online, and the Oh No Sumo team would add them to the playlist. "Short movies previously shared online, are projected for the public to enjoy, offering similar media to that sought out on their phones," explain the designers. "A community must be linked not only virtually but also physically." This particular pop-up theater is now a thing of the past, but keep your eyes peeled?this seemsto be atrend. [CollabCubed]
NEW YORK (TheWrap.com) - Lionsgate will bring exclusive video of "The Hunger Games: Catching Fire" and "I, Frankenstein" to Comic-Con, the studio announced on Wednesday. Lionsgate is the first film studio to reveal its plans for the fan confab in July; its panel will take place Saturday July 20.
Lionsgate's decision to bring "The Hunger Games" is a no-brainer. The first film was one of the most successful films in recent years, catering to the often underserved but equally rabid female fans who swarm the San Diego Convention Center every summer.
Fans crave new footage and stars at each panel, and they'll get the new footage. Lionsgate said it would provide an exclusive trailer and never-before-seen footage from "I, Frankenstein," which stars Aaron Eckhart in an adaptation of Kevin Gevioux's graphic novel.
Yet it remains unclear whether "Hunger Games" star Jennifer Lawrence will be in attendance, as Wednesday's announcement merely said "talent from both films will be in attendance."
A spokesperson for Lionsgate had no comment when TheWrap inquired, and Lawrence's publicist said it had yet to be determined as she is currently filming the latest X-Men movie, "Days of Future Past."
There are two big reasons to believe the Dolphins will have a more effective passing offense in 2013.
The first is that the team went out and added three targets to their receiving corps in an effort to give quarterback Ryan Tannehill more to work with than he had in his rookie season. Wide receiver Mike Wallace was the headline name in that group, but Wallace thinks that it is going to be the quality of a group including wide receiver Brandon Gibson and tight end Dustin Keller that winds up making life difficult for defenses.
?We all present a different type of challenge for the defense,? Wallace said, via the team?s website. ?We?re all different types of players. When you get us all together, it?s going to be fun.?
It?s not all newcomers, of course. Brian Hartline is back after a breakout 2012 season and he outlined the other reason why optimism is everywhere you look in Miami. That would be Tannehill with a year of experience under his belt.
?I mean everyone said, all the quote unquote experts say that there?s a big jump for a lot of guys from year one to year two and with Ryan I fully expect it,? Hartline said. ?I think at this point he?s focusing on taking it one day at a time, understanding that he has to go through all of camp and get into the season and play through the whole season, so there?s a lot of football to go to get evaluated on. But I couldn?t ask for more, he?s making every throw, his deep ball looks awesome, intermediate ball is great, he has great touch, you don?t feel like it?s a rocket coming into your hands. His improvement has been amazing.?
The revamped Dolphins offense is one of many things we?re excited to see in action when players put on pads upon their return to work in a month or so. If Wallace and Hartline are on point, opposing defenses may not feel the same way.
Seeing Game of Thrones play out on Facebook was the comic relief necessary for the oft depressing show. Seeing Game of Thrones characters pretend to have online dating profiles? Just as good, well, if only for Hodor's.
ANKARA, Turkey (AP) ? Turkish police on Tuesday detained at least 20 people allegedly involved in violent protests, as the country's prime minister continued to lash out at protesters ? and a BBC journalist ? he claimed were part of a conspiracy to harm Turkey.
Meanwhile, hundreds of protesters marched to Istanbul's central Taksim square, this time to denounce a court decision that ? pending trial ? freed police officer accused of killing a demonstrator during the anti-government protests that have swept the country since May 31. Police surrounded the square, blocking their access.
At least three demonstrators and a police officer were killed in the protests that began in Istanbul following a heavy-handed police clampdown on peaceful activists. They quickly turned into widespread expression of discontent with what critics have said is Prime Minister Recep Tayyip Erdogan's increasingly authoritarian way of governing.
Erdogan, who came to power a decade ago denies the accusation, and frequently points at elections in 2011 that returned his party to power for a third successive term with 50 percent of the vote.
One of the protesters was killed by a bullet fired by police during a demonstration in Ankara on June 1. A court on Monday released the officer from custody pending trial, on the grounds that the shooting may have been accidental. But some see the release as proof that Turkish authorities are too lenient toward police.
The state-run Anadolu Agency said police searched some 30 addresses in the capital, Ankara, and rounded up 20 people with alleged links to "terror" groups and suspected of "attacking police and the environment" during the protests.
Erdogan holds unspecified foreign forces, bankers and media outlets responsible for the protests that had largely subsided until the court freed the police officer.
In an address to members of his Islamic-rooted party in Parliament, Erdogan reiterated that the protests were orchestrated by forces wanting to prevent Turkey's rise.
He repeated his claim that the same conspiracy was at work in Brazil, saying both countries had paid off debts to the International Monetary Fund.
Mass rallies in Brazil were set off this month by a 10-cent hike in bus and subway fares in Sao Paulo, Rio de Janeiro and elsewhere. The protests soon moved beyond that issue to tap into widespread frustration in the South American nation over a range of issues, including high taxes and woeful public services.
"From the start, some people, internally and externally, have tried to portray the protests as totally innocent and just, and the police of having systematically used force," Erdogan said. "Certain media in Turkey were lead provocateurs. The foreign media took part in these operations."
He targeted a Turkish BBC reporter who tweeted about a forum held by protesters, where participants reportedly suggested a six-month boycott of goods that they said would help slow down the economy. Without mentioning her by name, Erdogan accused Selin Girit of being "part of a conspiracy against her own country."
"Their aim is to prevent democracy, to harm Turkey's economy, to hit tourism," Erdogan said.
Two days earlier, Ankara's mayor had accused Girit of being a British government agent and started a campaign on Twitter to apparently try to discredit her, prompting the BBC to issue a statement on Monday that said "it is unacceptable for our journalists to be directly targeted this way."
The BBC's global news director Peter Horrocks said "a large number of threatening messages" were sent to the reporter and he was concerned by the Turkish authorities' campaign to "discredit the BBC and intimidate its journalists."
On Monday, U.S. President Barack Obama spoke with Erdogan for the first time since the protests began. According to the White House, the two leaders discussed "the importance of nonviolence and of the rights to free expression" as well as the right of assembly and a free press.
Thorbjorn Jagland, the secretary-general of the 47-member Council of Europe, the continent's human rights watchdog which is based in Strasbourg, France, met with Erdogan in Ankara on Tuesday.
Jagland told The Associated Press that he had brought up a number of human rights issues concerning the protests, including the firing of tear gas by police inside an Istanbul hotel where some protesters had taken refuge.
"The Court of Human Rights in Strasbourg has a number of judgments related with this," Jagland said. "For instance, the court has said that the use of tear gas inside a room is not acceptable and this happened at one hotel at least."
"It is important to convey that the authorities have responsibility to react in a way that doesn't trigger further and more violence," he said.
In his speech Tuesday, Erdogan accused the hotel, Divan, and the Koc family that owns it ? Turkey's richest family ? of aiding criminals.
"Those who clashed with police went there. Its owners provided them with hospitality," Erdogan said. "You know it is against the law to harbor criminals."
______
AP writer Ezgi Akin in Ankara, and Umut Colak in Istanbul contributed.
Everyone knows they should pull to the side of the road when an ambulance with its blaring siren approaches. But what if you've got the windows rolled up, the radio blaring, and can't hear it coming? That's not a problem in Guayaquil, Ecuador, where to increase emergency response times, the ambulances actually hijack nearby AM and FM signals to let drivers know they're nearby.
The clever approach isn't illegal, either. A creative agency called Maruri Grey actually worked with the Radio Association of Ecuador to outfit ambulances with low-power broadcast antennas that override all AM and FM stations within a one kilometer radius of the vehicle. So anyone within the vicinity of the ambulance would be alerted it was coming well in advance, reducing the time it had to slow down for traffic ahead to clear.
And even though radio has been replaced by CDs and MP3 players as in-vehicle entertainment, response times for the ambulances was actually reduced by up to 40 percent with the new system. So now we just sit back and wait for pizza delivery drivers to install their own pirate radio transmitters to guarantee a piping hot pie delivered on time. [YouTube via Behance]
NAIROBI, Kenya (AP) ? Kenyan police say a terror suspect was killed in a gun battle and present weapons to the media. Hours later another suspect accused of terror links is dead in what police described as a shootout.
Witnesses and the family of the slain suspects tell a different story: That the suspects were arrested without a fight. One was handcuffed, and both were executed.
Human rights group, Muslim for Human Rights, says that police last week targeted the two terror suspects for execution. The group said Wednesday Kenya maintains a police death squad tasked with eliminating suspects with links to terror groups.
The head of Kenya's Anti-Terrorism Police Unit, Boniface Mwaniki, denied that a death squad exists, calling the allegations "outrageous."
LOS ANGELES (Reuters) - R&B singer Chris Brown, on probation for beating his former girlfriend, was charged on Tuesday with a hit-and-run and driving without a valid license in connection with a May 21 traffic accident in Los Angeles. Brown, 24, allegedly rear-ended another car and faces up to six months in jail on each misdemeanor charge, L.A. City Attorney spokesman Frank Mateljan said. He will be arraigned in Los Angeles Superior Court on July 15, Mateljan said. ...
The Board of Trustees of The City University of New York today appointed a nationally prominent educator, Dr. Rudolph F. Crew, Oregon?s chief education officer, former New York City schools chancellor and Miami-Dade school superintendent, as president of Medgar Evers College. Chancellor Matthew Goldstein recommended Dr. Crew after a national search.
Video of Dr. Crew?s remarks.
Dr. Crew has made it his life work to strengthen America?s public education system during a 30-year career that has spanned classroom teaching and leadership of the nation?s largest school districts. Since 2009 he has been a professor in the Rossier School of Education at the University of Southern California. He is also president of the K-12 division of Revolution Prep, which seeks to use technology to improve math instruction and graduation rates in urban school districts. As Oregon?s first chief education officer he was charged by Gov. John Kitzhaber with revamping public education, improving Oregon?s high school graduation rate and refashioning public education from kindergarten through college into an integrated system.
From left to right: CUNY Board of Trustees Vice Chairperson Philip Alfonso Berry, Dr. Rudolph Crew and Medgar Evers College Presidential Search Committee Chairperson and Trustee Valerie Lancaster Beal
In a joint statement, Board of Trustees Chairperson Benno Schmidt and Chancellor Goldstein said: ?Dr. Rudy Crew brings to Medgar Evers College an exemplary record of academic, administrative and governmental accomplishment, combined with classroom experience and a strong commitment to students. We are confident that, with his leadership, Medgar Evers College will achieve new levels of excellence for its dedicated students and faculty and strengthen its role with the community. The college was established in 1970 to honor the memory and ideals of the slain civil rights martyr and it is highly appropriate that it will be uplifted by a leader who is deeply committed to academic quality, equal access, and student success.?
Dr. Crew has stated that his mission is to ?improve student achievement, especially for poor and minority students.? To that end he worked closely with all stakeholders, first as New York City schools chancellor and later as superintendent of the Miami-Dade County Public Schools, to place those cities? lowest-performing schools in virtual districts whose boundaries were defined by student need, not geography, and used research-based practices to accelerate the pace of student learning.
Dr. Crew headed the New York City public schools from 1995-2000 ? the nation?s largest district, with a million students ? where he initiated many reforms, including adoption of curriculum standards for all schools, elimination of tenure for principals, and the introduction of school-based budgeting. As superintendent of the Miami-Dade County Public Schools from 2004-2008, with 356,000 students, he strengthened math instruction, created paths for more English-language learners and students of color and poverty to gain college entry with improved ACT and SAT scores, and started The Parent Academy serving more than 100,000 parents with courses and workshops to help them support their students? education.
He is the recipient of numerous awards, including the NAACP Educational Leadership Award, the Arthur Ashe Leadership Award, and the National Superintendent of the Year from the American Association of School Administrators in 2008.
Medgar Evers College, located in Crown Heights, Brooklyn, is a growing school of approximately 7,000 students who overwhelmingly are the first in their family to go to college. It offers both associate and baccalaureate degrees. At its founding it was named for the civil rights leader who was assassinated in 1963, with the hope that ?his ideals will inspire students and faculty ? in their pursuit of truth as the surest path to human freedom and social justice.?
The presidency of Medgar Evers College attracted an outstanding pool of more than 50 candidates, approximately the same number who applied for The City College presidency two years ago. The high quality of the three finalists ? all with exemplary qualifications, strong social justice records and a wealth of administrative experience ? testifies to the extensive outreach conducted by the University search committee, which was chaired by Trustee Valerie Lancaster Beal. The search committee selected 14 candidates for extensive interviews and approved three finalists to visit the campus. The committee included Trustees, the presidents of the Medgar Evers? Community Council and the alumni association, elected student government leaders, faculty representatives and a president of a CUNY senior college,
Soon after being named Oregon?s chief education officer in 2012, Dr. Crew ordered a third of the state?s 197 school districts to rewrite their academic goals because they had failed to seek improvement of at least one percentage point in high school graduation rates and third-grade reading and math scores. He also called for boosting educational achievement for the bottom 40 percent of students through greater use of technology and learning outside of class time, after school and during the summer, along with teacher-developed skill-building classes pegged to individual student needs and delivered online.
He has served in leadership positions for other diverse school districts, including Boston, Sacramento, several smaller California districts, and Tacoma, Wash. Dr. Crew has led school reform initiatives for a private foundation, headed the University of Washington?s Institute for K-12 Leadership and has been a university professor. Early in his career, he was a teacher and principal in middle and high schools in Massachusetts and California.
Dr. Crew was deputy superintendent for curriculum and instruction in the Boston Public Schools from 1985 to 1987. He was superintendent of the Sacramento City Unified School District from 1989 to 1993, and then served as superintendent of the Tacoma, Wash., School District from 1993 to 1995, when he was appointed chancellor of New York City?s public schools.
From 2000 to 2001, Dr. Crew was the executive director of the Institute for K-12 Leadership at the University of Washington, Seattle. He served as director of district reform initiatives at the Stupski Foundation from 2001 to 2004, when he was named superintendent of the Miami-Dade County Public Schools. Dr. Crew was president of Global Partnership Schools from 2008 to 2011. His book, Only Connect: The Way to Save Our Schools, was published in 2007. He has served on many boards, including the Lincoln Center for the Performing Arts and the Public Education Network.
Dr. Crew received a bachelor?s degree from Babson College in Wellesley, Mass., and a master?s and doctorate in education from the University of Massachusetts, Amherst. He taught at a career opportunity program in Massachusetts and at an alternative school in Pasadena, Calif., before moving into school and district administration.
CUNY has invested more than $300 million in new and newly renovated campus facilities at Medgar Evers College in recent years, including a new $235 million, state-of-the-art academic building and a $22 million School of Business and student support services building. Meanwhile, the college has expanded its faculty, particularly in the STEM fields (science, technology, engineering and mathematics), nursing, business, social work and library science.
The newest faculty hires bring impressive academic and professional credentials to Medgar Evers College, along with research backgrounds in venues as varied as NASA, South Africa and Vietnam, and in disciplines as cutting-edge as stem cells, remote sensing of greenhouse gases and renewable and sustainable energy.
About The City University of New York: The City University of New York is the nation?s leading urban public university. Founded in New York City in 1847, the University comprises 24 institutions: 11 senior colleges, seven community colleges, the William E. Macaulay Honors College at CUNY, the CUNY Graduate School and University Center, the CUNY Graduate School of Journalism, the CUNY School of Law, the CUNY School of Professional Studies and the CUNY School of Public Health. The University serves more than 269,000 degree-credit students and 218,083 adult, continuing and professional education students. College Now, the University?s academic enrichment program, is offered at CUNY campuses and more than 300 high schools throughout the five boroughs of New York City. The University offers online baccalaureate degrees through the School of Professional Studies and an individualized baccalaureate through the CUNY Baccalaureate Degree. Nearly 3 million unique visitors and 10 million page views are served each month via www.cuny.edu, the University?s website. # # # # #
By James Pomfret HONG KONG, June 23 (Reuters) - A former contractor for the U.S. National Security Agency, charged by the United States with espionage, was allowed to leave Hong Kong on Sunday, his final destination as yet unknown, because a U.S. request to have him arrested did not comply with the law, the Hong Kong government said. Edward Snowden left for Moscow on Sunday and his final destination may be Cuba, Ecuador, Iceland or Venezuela, according to various reports. The move is bound to infuriate Washington, wherever he ends up. "It's a shocker," said Simon Young, a law professor with Hong Kong University. "I thought he was going to stay and fight it out. The U.S. government will be irate." Russia's Interfax news agency quoted a source at the Aeroflot airline as saying there was a ticket in Snowden's name for a Moscow-Cuba flight. Itar-Tass news agency cited a source as saying Snowden would fly from Havana to Caracas, the Venezuelan capital. The South China Morning Post said his final destination might be Ecuador or Iceland. A spokesman for Russian President Vladimir Putin said he was unaware of Snowden's whereabouts or travel plans. The WikiLeaks anti-secrecy website said it helped Snowden find "political asylum in a democratic country". It did not elaborate, other than to say Snowden was "currently over Russian airspace" with WikiLeaks legal advisers. The White House had no comment on the WikiLeaks posting. WikiLeaks founder Julian Assange said last week he would not leave the sanctuary of the Ecuadorean Embassy in London even if Sweden stopped pursuing sexual assault claims against him because he feared arrest on the orders of the United States. U.S. authorities have charged Snowden with theft of U.S. government property, unauthorized communication of national defence information and wilful communication of classified communications intelligence to an unauthorized person, with the latter two charges falling under the U.S. Espionage Act. The United States had asked Hong Kong, a special administrative region (SAR) of China, to send Snowden home. "The U.S. government earlier on made a request to the HKSAR government for the issue of a provisional warrant of arrest against Mr Snowden," the Hong Kong government said in a statement. "Since the documents provided by the U.S. government did not fully comply with the legal requirements under Hong Kong law, the HKSAR government has requested the U.S. government to provide additional information ... As the HKSAR government has yet to have sufficient information to process the request for provisional warrant of arrest, there is no legal basis to restrict Mr Snowden from leaving Hong Kong." It did not say what further information it needed, but said Snowden left Hong Kong "on his own accord for a third country through a lawful and normal channel".
CHINA SAYS U.S. "BIGGEST VILLAIN" Hong Kong, a former British colony, reverted to Chinese rule in 1997 and although it retains an independent legal system, and its own extradition laws, Beijing has control over Hong Kong's foreign affairs. Some observers see Beijing's hand in Snowden's sudden departure. Putin's spokesman, Dmitry Peskov, said earlier this month that Russia would consider granting Snowden asylum if he were to ask for it and pro-Kremlin lawmakers supported the idea, but there has been no indication he has done so. Iceland refused on Friday to say whether it would grant asylum to Snowden, a former employee of contractor Booz Allen Hamilton who worked at an NSA facility in Hawaii. The South China Morning Post earlier quoted Snowden offering new details about the United States' spy activities, including accusations of U.S. hacking of Chinese mobile telephone companies and targeting China's Tsinghua University. Documents previously leaked by Snowden revealed that the NSA has access to vast amounts of internet data such as emails, chat rooms and video from large companies, including Facebook and Google, under a government programme known as Prism. In its statement, the Hong Kong government said it had written to the United States "requesting clarification" of earlier reports about the hacking of computer systems in Hong Kong by U.S. government agencies. "The HKSAR Government will continue to follow up on the matter, so as to protect the legal rights of the people of Hong Kong," it said. China's Xinhua news agency, referring to Snowden's accusations about the hacking of Chinese targets, said they were "clearly troubling signs". It added: "They demonstrate that the United States, which has long been trying to play innocent as a victim of cyber attacks, has turned out to be the biggest villain in our age." (Additional reporting by Fayen Wong in Shanghai; Nishant Kumar in Hong Kong; Alexei Anishchuk and Steve Gutterman in Moscow, and Tabassum Zakaria in Washington; Writing by Nick Macfie; Editing by Clarence Fernandez)
Hollywood's El Capitan Theater went from a relatively quiet historic landmark to raucous monster hangout to celebrate the return of Mike, Sully, and the gang in Monsters University. Amid the drums, gymnasts, confetti, and treats, the stars were all out, giving scary-good interviews.
June 21, 2013 ? Researchers in Berlin and Munich, Germany and Oxford, United Kingdom, have revealed that a protein well known for its role in Alzheimer's disease controls spindle development in muscle and leads to impaired movement in mice when the protein is absent or treated with inhibitors. The results, which are published in The EMBO Journal, suggest that drugs under development to target the beta-secretase-1 protein, which may be potential treatments for Alzheimer's disease, might produce unwanted side effects related to defective movement.
Alzheimer's disease is the most common form of dementia found in older adults. The World Health Organization estimates that approximately 18 million people worldwide have Alzheimer's disease. The number of people affected by the disease may increase to 34 million by 2025. Scientists know that the protein beta-secretase-1 or Bace1, a protease enzyme that breaks down proteins into smaller molecules, is involved in Alzheimer's disease. Bace1 cleaves the amyloid precursor protein and generates the damaging Abeta peptides that accumulate as plaques in the brain leading to disease. Now scientists have revealed in more detail how Bace1 works.
"Our results show that mice that lack Bace1 proteins or are treated with inhibitors of the enzyme have difficulties in coordination and walking and also show reduced muscle strength," remarked Carmen Birchmeier, one of the authors of the paper, Professor at the Max-Delbr?ck-Center for Molecular Medicine in Berlin, Germany, and an EMBO Member. "In addition, we were able to show that the combined activities of Bace1 and another protein, neuregulin-1 or Nrg1, are needed to sustain the muscle spindles in mice and to maintain motor coordination."
Muscle spindles are sensory organs that are found throughout the muscles of vertebrates. They are able to detect how muscles stretch and convey the perception of body position to the brain. The researchers used genetic analyses, biochemical studies and interference with pharmacological inhibitors to investigate how Bace1 works in mice. "If the signal strength of a specific form of neuregulin-1 known as IgNrg1 is gradually reduced, increasingly severe defects in the formation and maturation of muscle spindles are observed in mice. Furthermore, it appears that Bace1 is required for full IgNrg1 activity. The graded loss of IgNrg1 activity results in the animals having increasing difficulties with movement and coordination," says Cyril Cheret, the first author of the work.
Drug developers are interested in stopping the Bace1 protein in its tracks because it represents a promising route to treat Alzheimer's disease. If the protein were inhibited, it would interfere with the generation of the smaller damaging proteins that accumulate in the brain as amyloid plaques and would therefore provide some level of protection from the effects of the disease. "Our data indicate that one unwanted side effect of the long-term inhibition of Bace1 might be the disruption of muscle spindle formation and impairment of movement. This finding is relevant to scientists looking for ways to develop drugs that target the Bace1 protein and should be considered," says Birchmeier. Several Bace1 inhibitors are currently being tested in phase II and phase III clinical trials for the treatment of Alzheimer's disease.
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The above story is reprinted from materials provided by European Molecular Biology Organization, via EurekAlert!, a service of AAAS.
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Journal Reference:
Cyril Cheret, Michael Willem, Florence R Fricker, Hagen Wende, Annika Wulf-Goldenberg, Sabina Tahirovic, Klaus-Armin Nave, Paul Saftig, Christian Haass, Alistair N Garratt, David L Bennett, Carmen Birchmeier. Bace1 and Neuregulin-1 cooperate to control formation and maintenance of muscle spindles. The EMBO Journal, 2013; DOI: 10.1038/emboj.2013.146
Note: If no author is given, the source is cited instead.
It may not be the NBA Finals or Stanley Cup Playoffs, but the world's oldest tennis tournament has a solid following as well, particularly abroad. A new Wimbledon partnership with YouTube could help boost the competition's appeal stateside; for the first time, you'll be able to access video feeds from the two-week London event, live on Google's prized streaming site. Beginning this Monday, you can catch all the action on Wimbledon's YouTube channel, with Rolex footing the bill. You'll also find interviews, behind-the-scenes segments and press conference streams on the video site, along with past match highlights and other featured content. There's a teaser clip waiting for you just past the break.
Traders sold off bonds and stocks after the Fed expressed optimism about the future of the US economy, but Karlsson says he doubts the Fed will decrease its bond purchases anytime soon.
By Stefan Karlsson,?Guest blogger / June 21, 2013
Federal Reserve Chairman Ben Bernanke speaks during a news conference in Washington earlier this month. Some investors have expressed concern that the Fed will decrease its support of the economy, but Karlsson argues that the Fed is unlikely to do so anytime soon.
Susan Walsh/AP/File
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Both bonds and stocks, not just in the U.S. but interestingly in most other countries as well, have sold off heavily after the Fed expressed optimism about how the U.S. economy would develop, something that was interpreted as a signal that it might reduce its bond purchases.
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I however doubt that they will actually do that anytime soon. The U.S. economy is expanding, but very slowly, so slowly that the employment to population ratio was no higher in May 2013 than in May 2012.
And though Bernanke may have hinted that the criteria for drawing down QE is a 7% unemployment rate, the official statement keeps mentioning the 6.5% rate, along with expected inflation of 2.5%
Furthermore, the negative market reaction to the possibility of reduced QE may prove to be a case of "self-preventing prophecy". The large sell-off to the hint of such policy change could deter the Fed from actually going through with it.
The Christian Science Monitor has assembled a diverse group of the best economy-related bloggers out there. Our guest bloggers are not employed or directed by the Monitor and the views expressed are the bloggers' own, as is responsibility for the content of their blogs. To contact us about a blogger, click here. This post originally ran on stefanmikarlsson.blogspot.com.
NEW YORK (AP) ? Kroger says its customers are doing more of their shopping at its supermarkets, helped in part by the popularity of its store brands.
The country's largest traditional supermarket operator on Thursday raised its profit outlook for the year after reporting a higher quarterly net income that beat Wall Street expectations, although overall sales were shy of forecasts.
The Cincinnati-based company, which also owns Ralphs, Fry's and Food 4 Less, said sales at stores open at least a year rose 3.3 percent during the period, excluding fuel. The figure is a key metric because it strips out the impact of newly opened and closed locations.
The growth comes as Kroger and other traditional supermarket companies are working to adapt to a shifting industry. Shoppers are increasingly getting their groceries at big-box retailers like Target, drugstores and even dollar stores that have expanded their food sections.
The competition has taken its toll on some supermarket operators; SuperValu earlier this year sold off five of its major chains after struggling for years to fix its business.
But Kroger has been trying to keep pace in a variety of ways.
To improve the shopping experience, the company worked on shortening wait times at its checkouts, expanded its store-brand lineup and invested in making its loyalty program more sophisticated. It's also experimenting with different store formats that are more akin to big-box retailers and dollar stores.
In a conference call with analysts, Chief Operating Officer Rodney McMullen said shoppers made more trips to stores and bought more per visit during the quarter.
He also noted that Kroger's store brands now account for 26 percent of total units sold and 24 percent of total sales, excluding pharmacy and fuel.
Kroger and other retailers have been pushing their store brands more aggressively as a way to control their costs and fatten profit margins. McMullen noted that once customers try store brands, they don't really go back to name-brand products.
"Very seldom does the share go back to where it was," he said, noting that the loss brand names suffer is generally permanent.
Going forward, the company noted that it has "many contracts" with workers in local markets that have expired or will expire soon. It noted that it continues to be pressured by rising health care and pension costs, which many of its competitors do not have to deal with. That's because workers at big-box retailers aren't unionized.
For the quarter, The Kroger Co. earned $481 million, or 92 cents per share. That's compared with $439 million, or 78 cents per share, a year earlier.
Total revenue rose 3 percent to $30.04 billion.
Analysts on average expected a profit of 88 cents per share on revenue of $30.1 billion, according to FactSet.
Citing its stronger first-quarter results, Kroger increased its net earnings guidance for the year to a range of $2.73 to $2.80 per share, up from $2.71 to $2.79. It has said it expects a growth rate of 8 percent to 11 percent, helped in part by its plans to move into new markets.
Sales at established stores are still expected to grow between 2.5 percent and 3.5 percent for the year.
Shares fell $2.15, or 6.1 percent, to close at $32.98 Thursday amid a broader market decline.
Contact: David Orenstein david_orenstein@brown.edu 401-863-1862 Brown University
PROVIDENCE, R.I. [Brown University] Millions of times on a spring day there is a dramatic biomolecular tango where the flower, rather than adorning a dancer's teeth, is the performer. In this dance, the female pistil leads, the male pollen tubes follow, and at the finish, the tubes explode and die. A new paper in Current Biology describes the genetically prescribed dance steps of the pollen tube and how their expression destines the tube for self-sacrifice, allowing flowering plants to reproduce.
High school biology leaves off with this: In normal pollination, sperm-carrying pollen grains land on the pistil's tip, or stigma, and grow tubes down its style to reach the ovaries in the ovules at the pistil's base. Once the tubes reach their destination, they burst open and release their sperm to fertilize each of the two ovaries in every ovule.
In his lab at Brown University, Mark Johnson, associate professor of biology, studies the true complexity of intercellular communications that conduct this process with exquisite precision.
Among the fundamental biology questions at play in the sex lives of flowers, for example, are how cells recognize each other, know what to do, and know when to do it. Last year, for instance, Johnson and his research group showed how, for all the hundreds of pollen tubes that grow through the pistil, each ovule receives exactly two fertile sperm.
"As we drill into the details, it's a really great system for understanding how cellular identity is established and read by another cell," Johnson said. "The moves in the dance between the pollen and the pistil are a back-and-forth [of signals] as the pollen tube is growing. It's quite a dynamic system that happens over the course of a few hours."
Making the male listen
In the new paper, Johnson's group, led by third-year graduate student Alexander Leydon, sought to discover what convinces the male pollen tubes to stop growing and burst when they reach the ovule. Scientists have begun to understand the female's commands, but not the male's ability to listen.
What they knew from a prior study is that the gene expression in pollen tubes that had grown through a pistil was much different than that of pollen tubes grown in the lab. Leydon's first step, therefore, was to see which regulators of gene expression, or transcription factors, were at work in pistil-grown pollen tubes but not in the lab-grown ones. First they found one called MYB120 and through genomic analysis found two close associates: MYB101 and MYB97.
He tagged these with fluorescing proteins and found under the microscope that these transcription factors accumulated in the nuclei of the pollen tubes as they grew in the pistil.
Having placed them at the scene, Leydon then decided to see what happens when they aren't. He grew some normal arabadopsis plants, some in which a mutation disabled only one of the transcription factors, and other ones in which the genes for all three transcription factors were disabled. Then he took the pollen from each to pollinate normal flowers. The pollen tubes from all three plants reliably made it to ovules, but in 70 percent of the ovules encountered by the triple mutants, the pollen tubes didn't stop growing and then burst. Instead they kept growing, coiling, and remaining intact.
"The pollen tube gets to the right place, which you'd think is the hardest part," Johnson said. "But once it gets there it's unable to hear the message from the female to stop growing and burst."
From there the team looked for which pollen tube-expressed genes were being regulated by the MYB transcription factors. In pollen tubes that had grown through pistils, they found 11 that were grossly underexpressed in the mutated pollen tubes, compared to normal ones.
Finally, they looked at what those genes do. They encode a variety of tasks, but one in particular got Leydon's attention because it is responsible for the secretion of a protein called a thionin.
"For the thionin, I was especially excited because they have been described as being able to essentially burst open other cells," Leydon said. "That would be something that would be able to bind to a membrane and cause a pore to form."
In other words, expressing that gene could be pushing the pollen tube's self-destruct mechanism.
"This is not just a dialogue but a dialogue that ends in death," Leydon said. "It's a really well-controlled cell death situation."
Agricultural applications?
Future work, Johnson said, will include tracking down the relevant genes more fully and determining whether thionin is indeed the pollen tube buster that the genes and their MYB-related expression seem to indicate.
The work may also have implications beyond basic science, Johnson said.
Agronomists sometimes try to cross-breed species, such as barley and wheat, in hopes of creating new crops. That can be done if the different species are closely related and share the same number of chromosomes, but fertilization often fails at the pollen tube burst-and-release step.
Among crop plants, pollination means food.
"Understanding this molecular back-and-forth at all the different levels and stages will be useful to either engineer the process or introduce genetic diversity that will allow the reproductive process to be efficient even in difficult environmental conditions," Johnson said.
###
In addition to Leydon and Johnson, other Brown authors are Kristin Beale, Karolina Woroniecka, Elizabeth Castner, Jefferson Chen, and Casie Horgan. Ravishankar Palanivelu of the University of Arizona is a co-author. Chen, Castner, and Woroniecka were Brown undergraduatess who joined the project as BrownHoward Hughes Medical Institute Summer Scholars.
The National Science Foundation funded the study with grant IOS-1021917. The researchers used the Brown University Genomics Core Facility in their work.
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Contact: David Orenstein david_orenstein@brown.edu 401-863-1862 Brown University
PROVIDENCE, R.I. [Brown University] Millions of times on a spring day there is a dramatic biomolecular tango where the flower, rather than adorning a dancer's teeth, is the performer. In this dance, the female pistil leads, the male pollen tubes follow, and at the finish, the tubes explode and die. A new paper in Current Biology describes the genetically prescribed dance steps of the pollen tube and how their expression destines the tube for self-sacrifice, allowing flowering plants to reproduce.
High school biology leaves off with this: In normal pollination, sperm-carrying pollen grains land on the pistil's tip, or stigma, and grow tubes down its style to reach the ovaries in the ovules at the pistil's base. Once the tubes reach their destination, they burst open and release their sperm to fertilize each of the two ovaries in every ovule.
In his lab at Brown University, Mark Johnson, associate professor of biology, studies the true complexity of intercellular communications that conduct this process with exquisite precision.
Among the fundamental biology questions at play in the sex lives of flowers, for example, are how cells recognize each other, know what to do, and know when to do it. Last year, for instance, Johnson and his research group showed how, for all the hundreds of pollen tubes that grow through the pistil, each ovule receives exactly two fertile sperm.
"As we drill into the details, it's a really great system for understanding how cellular identity is established and read by another cell," Johnson said. "The moves in the dance between the pollen and the pistil are a back-and-forth [of signals] as the pollen tube is growing. It's quite a dynamic system that happens over the course of a few hours."
Making the male listen
In the new paper, Johnson's group, led by third-year graduate student Alexander Leydon, sought to discover what convinces the male pollen tubes to stop growing and burst when they reach the ovule. Scientists have begun to understand the female's commands, but not the male's ability to listen.
What they knew from a prior study is that the gene expression in pollen tubes that had grown through a pistil was much different than that of pollen tubes grown in the lab. Leydon's first step, therefore, was to see which regulators of gene expression, or transcription factors, were at work in pistil-grown pollen tubes but not in the lab-grown ones. First they found one called MYB120 and through genomic analysis found two close associates: MYB101 and MYB97.
He tagged these with fluorescing proteins and found under the microscope that these transcription factors accumulated in the nuclei of the pollen tubes as they grew in the pistil.
Having placed them at the scene, Leydon then decided to see what happens when they aren't. He grew some normal arabadopsis plants, some in which a mutation disabled only one of the transcription factors, and other ones in which the genes for all three transcription factors were disabled. Then he took the pollen from each to pollinate normal flowers. The pollen tubes from all three plants reliably made it to ovules, but in 70 percent of the ovules encountered by the triple mutants, the pollen tubes didn't stop growing and then burst. Instead they kept growing, coiling, and remaining intact.
"The pollen tube gets to the right place, which you'd think is the hardest part," Johnson said. "But once it gets there it's unable to hear the message from the female to stop growing and burst."
From there the team looked for which pollen tube-expressed genes were being regulated by the MYB transcription factors. In pollen tubes that had grown through pistils, they found 11 that were grossly underexpressed in the mutated pollen tubes, compared to normal ones.
Finally, they looked at what those genes do. They encode a variety of tasks, but one in particular got Leydon's attention because it is responsible for the secretion of a protein called a thionin.
"For the thionin, I was especially excited because they have been described as being able to essentially burst open other cells," Leydon said. "That would be something that would be able to bind to a membrane and cause a pore to form."
In other words, expressing that gene could be pushing the pollen tube's self-destruct mechanism.
"This is not just a dialogue but a dialogue that ends in death," Leydon said. "It's a really well-controlled cell death situation."
Agricultural applications?
Future work, Johnson said, will include tracking down the relevant genes more fully and determining whether thionin is indeed the pollen tube buster that the genes and their MYB-related expression seem to indicate.
The work may also have implications beyond basic science, Johnson said.
Agronomists sometimes try to cross-breed species, such as barley and wheat, in hopes of creating new crops. That can be done if the different species are closely related and share the same number of chromosomes, but fertilization often fails at the pollen tube burst-and-release step.
Among crop plants, pollination means food.
"Understanding this molecular back-and-forth at all the different levels and stages will be useful to either engineer the process or introduce genetic diversity that will allow the reproductive process to be efficient even in difficult environmental conditions," Johnson said.
###
In addition to Leydon and Johnson, other Brown authors are Kristin Beale, Karolina Woroniecka, Elizabeth Castner, Jefferson Chen, and Casie Horgan. Ravishankar Palanivelu of the University of Arizona is a co-author. Chen, Castner, and Woroniecka were Brown undergraduatess who joined the project as BrownHoward Hughes Medical Institute Summer Scholars.
The National Science Foundation funded the study with grant IOS-1021917. The researchers used the Brown University Genomics Core Facility in their work.
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?
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.