Heat

The above contraption may look a little funny, but it can be essential in the kitchen. Meet the heat diffuser. When you have a recipe that requires stove-top cooking over an extremely low and gentle flame, or are using a delicate cooking vessel such as a clay pot, a diffuser is perfect for softening and evenly spreading the heat. And it's great for eliminating hot spots. A heat diffuser (like the much-loved one pictured above from the Test Kitchen) is easy to use: Simply set the diffuser over the burner and place your pot or pan on top, then start cooking.

It's only been a week since Kobe Bryant and Dwyane Wade squared up in what turned out to be a pretty physical game. This time, the game actually matters. The Lakers host the Miami Heat Sunday at Staples Center, and there's certainly plenty of storylines involving the game. But the main one involves Bryant and Wade. Bryant has worn a plastic mask for the past week after Wade's hard foul in the 2011 All-Star game gave him a concussion, broken nose and whiplash on his neck.

INDIANA AT MIAMI 3 p.m. PDT Sunday. TV: None. Winners of 17 consecutive games, Miami is wiping away some of its smudges from earlier in the season while it cleans up on the rest of the NBA. Last week, the Heat posted a resounding comeback victory against New York after previously suffering a pair of 20-point defeats against the Knicks. Now the Heat looks to improve on its 0-2 record against Indiana, widely perceived as the only realistic challenger to the defending NBA champions in the Eastern Conference.

An international group of scientists has developed a material that can turn wasted heat into electricity with unprecedented efficiency, a discovery that may one day allow for more efficient cars and buildings. The finding was reported this week in the journal Nature. The material is crucial to creating devices called thermoelectric generators, which are designed to create an electrical charge when a difference in temperature exists across them. When such a difference exists, electrons move from one side to the other and a voltage is created which can be captured and used as electricity.

The Miami Heat has bigger problems than the disappearance of LeBron James. The entire team has gone missing. Just when it looked like it couldn't get any worse, it did, Dwyane Wade limping in and out of the lineup as the Heat moved within a loss of Miami mourning. In the series that won't stop spitting out subplots, the Dallas Mavericks kept taking it to the Heat, this time a 112-103 victory Thursday for a 3-2 lead in the NBA Finals. The Mavericks are a victory away from the first championship of their 31-year existence.

If cities were stocks, you'd want to short Phoenix. Of course, it's an easy city to pick on. The nation's 13th-largest metropolitan area crams 4.3 million people into a low bowl in a hot desert, where horrific heat waves and windstorms visit it regularly. And it depends on an improbable infrastructure to suck water from the distant (and dwindling) Colorado River. If the Gulf Coast's Hurricane Katrina and the Eastern Seaboard's Superstorm Sandy previewed how coastal cities can expect to fare as seas rise and storms strengthen, Phoenix - which also stands squarely in the cross hairs of climate change - pulls back the curtain on the future of inland empires.

Re "Romney crosses the immigration divide," Opinion, Sept. 23 Tamar Jacoby writes that many Republicans feel Mitt Romney "went too far in the heat of the primary and are glad to see him clarifying his position" on immigration. "Clarifying"? Shouldn't that be "changing" his position? During the primaries he touted, among other things, the self-deportation of millions of immigrants, an absurd proposal. And where does the idea come from that the primaries' heat is an excuse to spout any old nonsense, however mean-spirited or offensive, and then "clarify" it into a position less repugnant or inflammatory later?

As you find yourself using the grill this summer, here's a quick tip for holding the heat in the grill as you cook: Keep the lid closed. A grill works a lot like an oven, building up heat as long as it is sealed. And just as you lose heat every time you open the oven door, you can lose heat every time you open the grill. This may not be important when grilling quick-cooking items like fish or when you're simply searing, but it can become an issue when cooking thicker, denser cuts of meat that require longer cooking times.

The 2012 Boston Marathon is off and running, though there may not be quite as many participants as expected doing the actual running due to the potentially dangerous heat expected during Monday's race. The temperature was 69 degrees when the wheelchair racers left Hopkinton for the start of the race at 9:17 a.m. ET, and had risen to 71 when the women started at 9:32 and was up to 73 when the rest of the field took off at 10. By the time the runners get to Boston's Back Bay, they could be facing temperatures in the mid-80s.

Wesley Korir won the Boston Marathon on Monday, while Sharon Cherop was victorious in the women's race. Both runners are from Kenya, and both of them posted the slowest winning times since 1985. Both the slow times and the Kenyan sweep came as no surprise. Temperatures rose into the 80s during the race, leading to the slower paces for Korir, the 19th Kenyan men's winner in 22 years, and Cherop, the third Kenyan women's winner in the last five years. Last year, Geoffrey Mutai, also from Kenya, ran the fastest marathon in history (2 hours, three minutes, 2 seconds)