So suburb-ringed cities with low overall densities are much less efficient than those that are tightly-packed.

所以，总体密度的郊区环线城市的比那些紧密的城市很多。

You've probably heard of some of these. One is low density lipoprotein — also known as LDL cholesterol.

你可能听说过其中的一些。一种是密度脂蛋白——也被称为密度脂蛋白胆固醇。

They discovered that patients with depression had a lower density of synapses than healthy people of the same age.

他们发现，抑郁症患者的突触密度于同龄的健康人群。

But, despite their length, tails are incredibly low density, as low as a few hundred atoms per cubic centimeter.

但是，尽管尾巴很长，它的密度却得令人难以置信，到每立方厘米只有几百个原子。

They live in low densities, they're extremely well camouflaged, and when they move, they stay low to the ground.

它们数量稀少，又极善于伪装，在移动时，身体会尽量贴近地面。

First, there's Looser zones, which are bands of low bone density that form on the surface of the bone.

首先，会有Looser区，即在骨表面形成的密度带。 小编注：Looser区以瑞士外科医师Emil Looser命名。

It was also very low density, just what you'd expect for a loosely bound rock pile.

它的密度也很，正如你所想象的的松散的岩石堆。

Wyoming has the lowest population overall, but Alaska, which is by far, the largest state has the lowest population density.

蒙大拿州总体上人口最少，但阿拉斯加是远远最大的州，人口密度最。

These felines live at very low densities, and between two potential mates may be dozens of kilometers of harsh terrain.

这些猫类生物的密度非常，可能几十公里的恶劣地形才能遇到一个潜在的伴侣。

The comet has a very low density, similar to rubble-pile asteroids, so it was expected that the surface would be soft.

彗星的密度非常，类似于碎石堆积的小行星，所以它的表面应该会是柔软的。

Objects with lower density, like stuff that's made of organic materials, will allow more of the lower-energy X-rays to pass through.

密度的东西，像有机材质的东西，会让能级的X射线穿过。

Meanwhile, lighter substances with lower density, like plasma, move to its center.

同时，密度较的轻质物质，如等离子体，会向其中心移动。

Let's start with a fun city that has a pretty low population density.

让我们从一个人口密度很的有趣城市开始。

Whereas this is much squishier, this is low density polyethylene.

虽然它更柔软， 但它是密度聚乙烯。

However, even people who exercise often can have low bone density.

然而，即使是经常运动的人，骨密度也会偏。

Hargett was surprised when the doctors told him that he had low bone density.

当医生告诉他他的骨密度很时，Hargett 感到很惊讶。

When you have osteoporosis, you have low bone density.

当你患有骨质疏松症时，你的骨密度会降。

Small city, we have low density, make the design more romantic.

小城市，我们人口密度，让设计更加浪漫。

Then, you go to medium density, low density and higher density again.

然后，你去中等密度、密度再到高密度区域。

Category B is also considered low density.

B类也被认为是密度。