p***o
发帖数: 1252 | 1 There is a book called Circuit Simulation by Farid N. Najm.
It contains almost everything you need to know to build a practical
simulator for non-linear PDEs, not to mention the relationship
between thermal elements and their electronic counterparts
(e.g. conductance/capacitance, temperature vs. voltage).
Once you know how to build a simulator, you'll have better idea
on building optimization tools - at least you can use some
probabilistic metaheuristics like simulated annealing and
evolutionary... 阅读全帖 |
|
d******c
发帖数: 2407 | 2 The Landscape of Parallel Computing Research - UC Berkeley EECS
1. Old CW: Power is free, but transistors are expensive.
· New CW is the “Power wall”: Power is expensive, but transistors are “
free”. That
is, we can put more transistors on a chip than we have the power to turn on.
2. Old CW: If you worry about power, the only concern is dynamic power.
· New CW: For desktops and servers, static power due to leakage can be 40%
of
total power. (See Section 4.1.)
3. Old CW: Monolithic uniprocessors ... 阅读全帖 |
|
a*****t
发帖数: 81 | 3
200 mv ? is it possible ?
Normally, rest membrane potential of neurons is about minus 50 to 80 mv,
as the outside membrane be the reference potential. For some astrocytes,
the value is about minus 20 to 30 mv. I can not recall the value for muscle
cells, but it is also minus.
You are right that you can assume the potential is distributed on the
membrane(double layer). Because compared with the resistance and capacitance
of the membrane, intra- and extracellular contributions c |
|
|
r***e
发帖数: 2539 | 5 上次和大家讨论cancer stem cell 或者cancer initiating cell的问题，受益匪浅。当
时我认为primary tumor中可能存在一小部分的CSC，但是通常用的limited dilution在
免疫缺陷老鼠中长瘤的的方法说服力不强。当时我举例说established cancer cell li
ne比如说HELA，做transplantation的话，也能看到类似的结果，而HELA细胞里难道也有
cancer stem cell吗？今天看到几篇文章，竟然就是从细胞株中分离CSC，他们的说法是
"An alternative approach for isolating stem cell populations is through enri
chment of side population (SP) cells, SP cells are identified by the capacit
y to efflux Hoechst dye"，就是说这些细胞能通过这个机制获得drung resistance。
http://cancerres.aac... 阅读全帖 |
|
p******d
发帖数: 3737 | 6 CSC这个概念看你怎么看。我觉得本身它是个毫无意义的概念，除非和临床结合。
临床上CSC的提出一部分原因是因为有一小部分的细胞对chemo有强烈的抵抗能力，在
chemo后导致
肿瘤的复发。这就和你说的sp细胞的概念扯上关系了，因为后来发现这些细胞表达的基
因例如
multiple drug resistant protein导致chemo drug被泵出了细胞外，导致了细胞对这
些药
物耐受，这也是sp细胞用来寻找各个组织干细胞的一个起源。
另外一个临床的原因是转移。很显然，转移的细胞导致新的肿瘤灶形成。这也是为啥
Weinberg实验
室会把CSC和EMT联系在一起了。
不论人类原发肿瘤本身或者建立的细胞系，在细胞表型上肿瘤常常是heterogeneous的
，病理上往
往要划定一定的百分比标准来判断是否某一标志物阳性，例如淋巴瘤的CD20或者乳腺癌
的ER受
体。还有关于你说的hela细胞，hela也是从人肿瘤里面分离出来的永生化细胞株。永生
化或者单克
隆筛选不等于获得的细胞株中每个细胞就在表型上完全一致。根据表面标志物来分，这
些细胞仍然
heterogeneous，尽管遗传... 阅读全帖 |
|
s*******3
发帖数: 3 | 7
。当
li
也有
法是
enri
capacit
resistan |
|
