At the core of most problems caused by the web is the business model used by the most popular networks. Apologies for the string of sentences, it was formatted for twitter.

Notd now makes publishing a newsletter simpler and less expensive than any other way

Postd is a new kind of public network, like Notd, except it's not for subscriptions and you can also post videos. If you want to read this as a series of tweets, go to Postd's twitter page.

Top Democratic presidential contenders talked tough Wednesday on cutting climate-damaging emissions from oil, gas and coal, turning their focus to global warming in a marathon evening of town halls that gave the candidates a chance to distinguish themselves on a topic of growing importance to their party's liberal base. The lengthy climate conversations promised to hand Republicans ammunition for next year's general election fight by emphasizing one common element in the Democrats' climate change plans: their overwhelming — and overwhelmingly costly — scope.

Democratic presidential candidates are releasing their plans to address climate change ahead of a series of town halls on the issue as the party's base increasingly demands aggressive action. New Jersey Sen. Cory Booker, Massachusetts Sen. Elizabeth Warren and former Obama Cabinet member Julián Castro laid out their plans Tuesday. Minnesota Sen. Amy Klobuchar released hers over the weekend.

The government agency that manages Australia's Great Barrier Reef has downgraded its outlook for the corals' condition from "poor" to "very poor" due to warming oceans. The report issued Friday finds the greatest threat to the reef remains climate change. The other threats are associated with coastal development, land-based water runoff and human activity such as illegal fishing.

"President Donald Trump is accumulating primary challengers, which should make both Democrats and never-Trump Republicans happy. Prominent never-Trumpers, however, have balked at the campaign of Joe Walsh and seem at best lukewarm about the prospect of Mark Sanford entering the race. They shouldn’t be," says columnist Karl W. Smith. "History shows that presidents who face strong primary challenges go on to lose the general election."

"Go ahead and forgive yourself if you find some details of Vice President Mike Pence’s visit to Ireland confusing," says columnist Timothy L. O'Brien. "Although Pence has official meetings in Dublin (on Ireland’s east coast) he and his federal entourage have found lodging in Doonbeg (on Ireland’s west coast). Why Doonbeg? Well, Pence has ancestral ties to Doonbeg, about which he waxed poetic on Tuesday as he explained his decision to burden his team and U.S. taxpayers by staying 125 miles away from Dublin. Even better: Donald Trump owns a hotel and golf course in Doonbeg, which Pence also found inviting."

"There is a special kind of stupidity that approaches terrible and repeating problems with an obstinate assurance of what the answer will or won’t be. Or maybe it’s cynicism — just digging in against any sort of movement that might be politically dangerous, even if it promises to break the paralysis of doing nothing repeatedly," says columnist Rudolph Bush. "By now, with more than 200 mass shootings since Columbine and already 33 this year, we have to acknowledge that we are a deeply unwell nation. Or at least we are a nation cultivating terribly unwell people with the nihilistic will to kill all in their paths."

A Christchurch businessman who shared a video of worshippers being slaughtered at a New Zealand mosque was sentenced on Tuesday to 21 months in prison. Philip Arps had earlier pleaded guilty to two counts of distributing the video, which was livestreamed on Facebook by a gunman on March 15 as he began killing 51 people at two mosques. Christchurch District Court Judge Stephen O'Driscoll said that when questioned about the video, Arps had described it as "awesome" and had shown no empathy toward the victims.

The governing body of track argued in court that Olympic champion Caster Semenya is "biologically male" and that is the reason she should reduce her natural testosterone to be allowed to compete in female competitions, according to documents released publicly for the first time on Tuesday and which provide new insight into a bitter legal battle.

Egypt's first democratically elected president, Islamist leader Mohammed Morsi, was buried under heavy security early on Tuesday, a day after his dramatic collapse and death inside a Cairo courtroom, his family and a member of his defense team said. Morsi's family attended funeral prayers in the mosque of Cairo's Tora prison, followed by the burial at a cemetery in the Egyptian capital's eastern district of Nasr City.