c***x
发帖数: 628 | 1 What "Lockup" Really Means
by Jonathan Thayer on January 09, 2013
I receive a good number of questions regarding what "lockup" really means
and the differences in the different percentages.
I typically don't quote other sources often, but Mr. Jim El Nabli (a BMW
enthusiast) stated it better than I can. (I only edited some of the spelling
mistakes and formatted it a bit different than his original email.)
In a standard differential, if one wheel loses traction, it will get all the
power and will ... 阅读全帖 |
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l********e
发帖数: 3632 | 2 我仔细想了想，还真不知道Differential Geometry到底是研究什么的。
我能想到的就是Differentiable manifold, differentiable maps, tangent bundle,
affine connection, curvature tensor等。再有其他东西就算其他比如Differential
topology or Riemannian geometry之类的研究对象了。
所以上述这些科目的参考书中都会有相应的微分几何的介绍。
比如do Carmo Riemannian geometry中就有不错的介绍。他的特点是书写得很几何化，
不是那么抽象。Burcker 写的Introduction to Differential Topology也可以作为入
门。还有Helgason 的名著Differential Geometry Lie Groups and Symmetric Spaces
中也有介绍。所以单独的微分几何书并不是很有趣，有趣的是当微分几何应用到其他领
域中的时候。
如果偏爱中文，白正国,沈一兵的Riemann几何初步或... 阅读全帖 |
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q**j
发帖数: 10612 | 3 下午换differential oil，拧fill plug螺丝花了2个钟头，干活20分钟，打扫20分钟。
太不爽了。那种特别头疼的螺丝一般都是如何给搞定的？我这个搞下来快给拧坏了。
另外我看文章讨论，differential不是为了让左右轮子跑得不一样快么？这个问题应该
是后轮比较严重？所以我的MDX上面rear differential在后面，前面的differential应
该和transmission在一起。可是这个camry只有一个diff在前面，那后面的轮子怎么办？
请高手给解释一下。 |
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s***z
发帖数: 631 | 4 车是 4WD。
这里dealer报价是rear differential service $199。 有个coupon给$99。
查个manual, 是这么说的
Replace VTM-4 rear differential fluid：
Driving inmountainous areas at very low vehicle speeds or trailer
towing results in higher level of mechanical (shear) stress to fluid
or frequently fully loaded. This requires differential fluid changes
more frequently than recommended by theMaintenanceMinder.
If you regularly drive your vehicle under these conditions, have the
differential fluid changed at 7,500miles (12,000 ... 阅读全帖 |
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e******s
发帖数: 309 | 5 Maint Manual只提到了VTM-4 Differential Fluid，网上查是rear。根本没提front
differential fluid
一些forum有的说MDX没有front differential，有的说front就是transfer case fluid
，有的说front differential自己也有更换周期
有明白的大侠指点一下吗？ |
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c***x
发帖数: 628 | 6 And this.
U.S. Pat. No. 3,831,462
"When one of the wheels loses traction with the surface of the road, the
limited slipdifferential or drive mechanism begins to differentiate and
power is transmitted from the engine to the wheel which has lost traction
and that wheel consequently begins to spin while the other wheel is not
driven. When such a situation occurs, it is essential for the differential
to lock so that the side gears are locked with respect to the carrier.
Consequently, both of the si... 阅读全帖 |
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f*****y
发帖数: 142 | 7 一个Datsun的忠实的fan，从dealer mechanic training material里面摘录的。
感觉非常非常的详尽，希望可以帮助大家分析可能有的问题。因为是个表格形式，
所以copy的时候不一定效果好，大家可以尽量看连接。
http://www.zparts.com/zptech/difdiag_p1.html
俺的小破车的典型问题就是那个howl，尤其是slow down的时候，
非常的明显，有节奏的呜呜的叫。而且当一边轮子着地，另外
一边jack up的时候，如果在档上，按理应该只有非常小的slack，
可是俺的小破车轮子可以来回转动1cm左右（看brake disc的外径）。
低速突然加速或者松开油门的时候，也有clunk的问题。前一段换了
wheel bearing，一个axle还是不能解决问题。:(
1978 DATSUN DIFFERENTIAL SERVICE GUIDE
DIFFERENTIAL ROAD TEST AND DIAGNOSIS
INTRODUCTION:
BEFORE you remove the differential f |
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j*********n
发帖数: 6034 | 8 differential有盖子？
后differential就一个孔，前differential不清楚，好似可以ｄｒａｉｎ。 |
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s***z
发帖数: 631 | 9 在大约2万迈的时候因为有些漏油，做了 rear differential service （保修期内）
现在有6.5 万迈了，需要做一次 rear differential service 吗？
另外，是不是前轮没有differential fluid 的问题？
谢谢 |
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T*********0
发帖数: 4816 | 10 好像是这样的，如果不漏油，不需要differential service的。
几个月前，自己把2002 Volvo 70XC的rear differential oil那地方拧开，想给这个已经
130k miles的老车换一下differential fuid，打开螺丝一看，fluid oil还很满，很
fresh，立马把螺丝给拧上了。再也不用打开它去看了。
没想误导谁，只想分享一下我自己的经历。
10 |
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g*****9
发帖数: 4125 | 11 You maybe ok.
If you are in northern part (very short cooling season and does not get very
hot outside) more than 10F temperature differential is good enough.
You need to measure the temperature differential after the system has been
running for a while (not you just turn on), uninsulated duct could take more
than 30min for the system to stablize. Also did you measure in the room
closest to the AC for furtherest away from the AC.
Also it is harder for AC to main the temperature differential if y |
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e***y
发帖数: 4307 | 12 很严重的甲状腺癌是anaplastic，跟poorly differentiated cancer还是很不一样的。
如果是poorly differentiated的papillary或者follicular cancer，早期的症状跟
well differentiated的不会有很大区别
糟。 |
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w********2
发帖数: 16371 | 13 【 以下文字转载自 Stock 讨论区 】
发信人: wavelets01 (信箱), 信区: Stock
标 题: Apple: Small iPad to Eliminate Android Differentiation, Says Piper
发信站: BBS 未名空间站 (Mon Jul 9 11:45:03 2012, 美东)
Mon, 09 Jul 2012 15:41:55
By Tiernan Ray
Piper Jaffray's Gene Munster this morning reiterates an Overweight rating on
shares of Apple (AAPL) and a $910 price target, writing that recent news
reports the company will produce a smaller iPad by the end of this year are
different from the 2013 introduction he'd been expecting, bu... 阅读全帖 |
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k********e
发帖数: 702 | 14 急！SQL Server 2005
数据崩溃被覆盖，fullbackup被覆盖
唯一完整的是一天前的differential backup
（最近的fullbackup是一个月前，所以differential backup里面很可能有很多数据）
请问能从里面提取出部分有效数据吗？有多少算多少。。。。死马当活马医了！ |
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g***l
发帖数: 18555 | 15 我觉得是可以恢复的，再建一个新的不同名字的DATABASE，RESTORE一个月FULL BACKUP
，APPLY DIFFERENTIAL，应该可以，但要保证有足够的空间，单从DIFFERENTIAL里是提不出数据的。 |
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c*****d
发帖数: 6045 | 16 正常情况下没有full backup是不能用differential backup的
但是如果你是从一个空database开始，differential backup包含了之后的所有change
，这个从理论上讲应该还是可以的
我不知道ms sql server怎么做这种情况的恢复，oracle是可以恢复的 |
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f******5
发帖数: 7 | 17 *Job Description:*
A post-doctoral position is available in Dr. Sing Yian Chew’s laboratory http://www.ntu.edu.sg/home/sychew at the School of Chemical & Biomedical Engineering, Nanyang Technological University, Singapore, to study the effects of nanotopography on cell-substrate interactions and stem cell differentiation.
*Job requirements:*
Applicants should have at least a Ph.D. and skilled in cell biology and
stem cell differentiation and possess relevant experimental skills.
Applicants wit |
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i*********0
发帖数: 915 | 18 What happens if ES cell oct4 gene is silenced by shRNA? Directly go for
differentiation or just lose the ES cell identity? Do I need to apply some
news TFs to achieve a differentiation after OCt4 knockdown? |
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j******i
发帖数: 6 | 19 To anybody who knows black-scholes model and stochastic differential
equation or anybody who knows control theory.
dS=αSdt+βSdB, S denote the price of a stock depends on t,S(t), α is the
drift or rate of return, β is the volatility, B is brownian motion.
How do I incorporate the control parameter γ , and a number “ L “defined
as dN/dS, where N denotes the amount of asset traded and S denote the asset
price so that dS=(αS+γ/L)dt+βSdB
defines a differential equation.
Thank you in advance |
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j******i
发帖数: 6 | 20 To anybody who knows black-scholes model and stochastic differential
equation or anybody who knows control theory.
dS=αSdt+βSdB, S denote the price of a stock depends on t,S(t), α is the
drift or rate of return, β is the volatility, B is brownian motion.
How do I incorporate the control parameter γ , and a number “ L “defined
as dN/dS, where N denotes the amount of asset traded and S denote the asset
price so that dS=(αS+γ/L)dt+βSdB
defines a differential equation.
Thank you in advance |
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j********3
发帖数: 9 | 21 Thanks again for the responses. I understand that if f(t) is differentiable, then the FT of f'(t) is iwF(w).
I am wondering if I can find a f(t) that is not differentiable yet |w||F(w)| is in L1.
It does not seem obvious to me that such f(t) does not exist?
Also, I still interested in knowing how to prove the statement in my previous post.
Thanks again for helping, I really appreciate it. |
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w**a
发帖数: 1024 | 22 在differential forms 里面那个 wedge product '/\'
w = f(x1,x2,x3) dx1 /\ dx2 /\ dx3
dx_i 不是切空间的范函吗？ 并没有无限小的意思啊，
为什么 dx1 /\ dx2 /\ dx3 就是体积而且可以积分？
还有外微分的意义到底是什么？ 不理解。
感觉differential forms 那些运算就是在玩弄符号啊。
请大虾指教。 |
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j******i
发帖数: 6 | 23 To anybody who knows black-scholes model and stochastic differential
equation or anybody who knows control theory.
dS=αSdt+βSdB, S denote the price of a stock depends on S(t), α is the
drift or rate of return, β is the volatility, B is brownian motion.
How do I incorporate the control parameter γ , and a number “ L “defined
as dN/dS, where N denotes the amount of asset traded and S denote the asset
price so that dS=(αS+γ/L)dt+βSdB
defines a differential equation.
Thank you in advance |
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j******i
发帖数: 6 | 24 To anybody who knows black-scholes model and stochastic differential
equation or anybody who knows control theory.
dS=αSdt+βSdB, S denote the price of a stock depends on t,S(t), α is the
drift or rate of return, β is the volatility, B is brownian motion.
How do I incorporate the control parameter γ , and a number “ L “defined
as dN/dS, where N denotes the amount of asset traded and S denote the asset
price so that dS=(αS+γ/L)dt+βSdB
defines a differential equation.
Thank you in advance |
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n***p
发帖数: 7668 | 25 Is that a differential equation? Why does it have dx in both the numerator
and the denominator? Can they be cancelled? If yes, then there will not be
dx and how can it be a differential equation? |
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j******i
发帖数: 6 | 26 To anybody who knows black-scholes model and stochastic differential
equation or anybody who knows control theory.
dS=αSdt+βSdB, S denote the price of a stock depends on t,S(t), α is the
drift or rate of return, β is the volatility, B is brownian motion.
How do I incorporate the control parameter γ , and a number “ L “defined
as dN/dS, where N denotes the amount of asset traded and S denote the asset
price so that dS=(αS+γ/L)dt+βSdB
defines a differential equation.
Thank you in advance |
|
e***y
发帖数: 4307 | 27 我老婆也得了甲状腺癌，已经动过两次手术了，也发现了肺转移。她的诊断是
moderately differentiated的，不过是diffuse sclerosing variant，所以相对来说
比classic variant更aggressive一点。虽然甲状腺癌相对发展比较慢，但是现代医学
的治疗手段也非常有限，像前面回帖说的如果对i-131不敏感的话基本上是没有办法的
。很不幸我老婆就是这种情况。现在只能定期检查希望肺转移没有长大。clinical
trial的药副作用很大，不到必要时是不会考虑的，而且只能延长几个月的寿命。
甲状腺癌在年轻人中其实发病率不低的，我们认识好几个30岁左右的病人，男女都有。
我在inspire.com上甲状腺癌论坛上也看到几个poorly differentiated的20出头的女病
人。以往甲状腺癌的病例比较少，经验丰富的医生并不多，因此去好的医院非常重要。
其实你去的都是非常好的医院了，应该相信你的医生。这个病最有效的治疗方法是手术
，最好把颈部的可疑淋巴结都清理掉，也方便日后用tg跟踪。若发现肺转移，预后要差
点，但是很多人（50％以上）都... 阅读全帖 |
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t****g
发帖数: 362 | 28 谢谢你的回复，希望你太太早点好一起，我们一起加油
现在的医生给我诊断是 poorly differentiated follicular cancer，这段时间一直在
做各种各样的检查，已经做完了WBS， PET Scan，radioactive iodine 150mc? (不知
道单位怎么写)，今天又去做了WBS，医生说根据检查结果来看应该没有暂时，淋巴，肺
等都没有。一个月之后去抽血，6周之后再去nuclear medicine 那边再去做检查，具体
做什么到时候再看。
我在网上查的poorly differentiated这种就是比较aggressive，而且follicular
cancer是经过血液远处扩散，现在的情况只是说暂时安全，不知道什么时候会复发。 |
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n********d
发帖数: 526 | 29 网上乱逛时看到现在的F150 Raptor新加了Torsen front differential。想到一个问题
，这车在2WD状态下，前轴没有动力，这时这个Torsen differential有作用吗，还是和
open的一样？ |
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c***x
发帖数: 628 | 30 open能传动的最大动力等于最小摩擦的轮子x2。所以一侧轮子摩擦越小，能传输的总动
力就越小。
ATB不算LSD因为它控制torque分配而不是限制两轮相对速度 － 它们是torque bias
differential。
LSD之所以叫LSD是因为它限制两轮间相对速度 － 因此叫limited slip differential。
Open |
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m**u
发帖数: 632 | 31 手动, 后轮驱动, DEALER给我的建议上有differential和transmission oil,但是我记
得这些油在正常情况下应该是免维护的吧? |
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s*******t
发帖数: 2896 | 32 differential no，transmission yes. |
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g******s
发帖数: 410 | 33 二手车，RWD，60K maintenance一定要换differential oil和transmission oil吗？自
己不怎么会动手，到dealer那去换比较贵啊。 |
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d***8
发帖数: 2039 | 34 Differential oil, 我30K miles 换一次， drain and refill，挺简单的。
Transmission oil，也是drain 安定refill。 |
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g******s
发帖数: 410 | 35 If previous owner(s) had never changed differential oil, do I still need to
change it? I heard that if it's never been exchanged, I'd better leave it as
it. Any suggeustion/recommendation? Thanks a lot!【 在 ds008 (ds008) 的大作
中提到: 】 |
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t********9
发帖数: 641 | 36 请问要不要紧？
他们还要我换differential oil.
我的车是jeep liberty 才38000miles, 07年的车 |
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r***y
发帖数: 4379 | 37 differential fluid 简单
brake fluid 要卸掉车轮, 而且要有个人帮你在车里踩才能bleed, 新手危险, 麻烦
trans 没折腾过 |
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e******g
发帖数: 5344 | 38 车子快1万5千迈了，因为地方湿冷，经常开山路和downtown，属于手册上的severe情况
（不过美国除了加州哪儿都是severe吧。。）看手册说transmission fluid，brake
fluid和power steering fluid要换了，differential倒是可以等到3万迈再换。对
dealer用的fluid不放心，打算自己买好牌子的带去pay dealer个labor就好了，请问大
家对这些fluid有啥品牌推荐的？sythentic有必要否？我机油倒是一直用的castrol
edge 5w30,对其他fluid没研究，先谢过！ |
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m***j
发帖数: 533 | 39 现在的differential基本上可以认为不需要service的。如果你想做的话可以每5年/10
万mi换一次fluid就够了。之前的service是因为漏油所以属于维修。只要不坏你并不需
要保养它。 |
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m***j
发帖数: 533 | 40 你看清楚点，你那个15k一次是transfer case还是differential？据我所知现在所有车
厂的小型车没几个要求定期更换diff oil的，就算需要周期也非常长至少50k miles以
上。 |
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f*********r
发帖数: 7485 | 41 在要越野的皮卡上面。越野的不多，就是national park 裡面的4x4的路。本人長得醜
，常常一個人在鳥不拉那個的地方混。怕車被陷但是有點窮（擦，是非常的窮）想省錢
。有沒有人說說這個東西該買還是不該買。
準確的說，我指的的toyata tacoma的TRD off road package。多花3000，不過可以有
很多好東西，尤其是這個rear locking differential。 |
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f*****d
发帖数: 1391 | 42 很多美国后驱卡车都有locking rear differential。 |
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f*********r
发帖数: 7485 | 43 是手動的
但是即使是自動，你比較f150跟tacoma的比法也太不靠譜了
你說的f150 4x4 V6 29K的，是regular cab,toyata 4x4 4缸的regular cab, 才24K，
兩者車身長度toyata 6.1feet, ford 6.5feet。
如果到29K這個價位，toyata是access cab.我覺得access cab比regular cab好太多了
，雖然卡車bed短半尺，但是車座後面的半尺太有用了。然後toyata也是V6 4x4
要往上面加東西，比如這個rear locking diferential，都需要格外加錢。豐田有越野
包，加很多跟越野有關的東西，福特就沒有。而且福特的網站奇爛無比，連是不是四驅
的信息都給不出來。那個rear locking differential，到底要多少錢，我也查不出來。
豐田的這個中型皮卡，本來就是考慮有越野用途的。而福特的F150是full size truck
，然後它有縮小版本，那個6.5feet就是一個大皮卡的縮小版本和便宜版本，所以沒這
些考慮一點都不奇怪。F150的越野版本應該是有的，但是... 阅读全帖 |
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B*Z
发帖数: 7062 | 44 front differential fluid一般都和transmission fluid在一起了。（也就是没有。）
transfer case 用gear oil，一代MDX一开始没有，后来加上了。你要按照车的年代找。
fluid |
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d****9
发帖数: 58 | 45 屋内temperature differential （between 进风口与出风口?）只有11F, inspector说
至少要高于14F才满足要求。
请问什么原因会造成这个问题？
多谢指教！！ |
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d****9
发帖数: 58 | 46 Hi gezhi89, thank you so much for your reply!! I have enjoyed reading many
of your 贴子。 也很欣赏你热心帮助家居生活新手！
Below is the words that I copied from the inspection report. The temperature
differential is between the intake and the output. The AC is brandnew and
had been running for a few days before the measurement was taken.
I am going to meet with the HVAC contractor tomorrow. Any suggestions about
what I should ask him? |
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d*******i
发帖数: 472 | 47 【 以下文字转载自 Medicalpractice 讨论区 】
发信人: djshaofei (行体艺术), 信区: Medicalpractice
标 题: 荨麻疹与寄生虫？大牛们帮忙做个Differential diagnosis
发信站: BBS 未名空间站 (Fri Oct 25 06:45:45 2013, 美东)
正文有点长，但自认为写的还算有条理，希望大牛耐心看完，帮忙分析下，bow
荨麻疹两周了，今天深圳一位主任医生看到症状也确认是荨麻疹
症状很规律的和进食有关，一般都在饭后10分钟内出现症状，持续若干小时后消失
一般而言，晚餐后最严重，早上空腹时完全无症状。
奇妙在于，和食物品种似乎关系不大
香蕉、咖啡、冬枣、食堂炒菜盖浇饭、冻柠茶等等
我因而觉得似乎不是事物本身直接引起的，我的身体似乎不会奇特到突然（之前三十年
从未出现）对如此多的食物品种过敏
我感觉他们的共性是糖，而糖快速吸收后给了体内的各种微生物突然的高营养，它们兴
奋之后，代谢副产物（或生物体本身）造成的过敏。
剩下的寄生虫（或细菌、酵母，暂时先不做结论）感染源和感染途径我就不懂了，... 阅读全帖 |
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c***c
发帖数: 113 | 48 准备申请绿卡，单位不支持博后办EB1B，准备办EB1A。想多攒点审稿经历。请好心人帮
忙推荐一些相关的审稿机会。
Research Areas:
currently focus on osteoarthritis and chondrocyte biology, including the
role of NFAT1, RunX2 and BSP joint disorders and chondrocyte function,
epigenetic regulation of gene expression.
Previously studies include genetic dissection of rheumatoid diseases in MRL/
lpr mice and T cell differentiation.
I graduated from medical college in China so I can review clinically related
manuscripts.
I've reviewed some manuscripts for me... 阅读全帖 |
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a****p
发帖数: 39 | 49 真诚求审稿机会！
方向包括gene fusion, mechanism of lung cancer,cell differentiation。
近期已经发了数十封邮件骚扰编辑，部分回信说已加入list，然后就没下文了。
各位大牛各位朋友帮帮忙，重谢！！ |
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g*****y
发帖数: 215 | 50 Graduate Students:
Earlier this week, the Board of Trustees adopted a tuition and fee
increase for Purdue. The engineering differential fees that you pay will
increase in August as a result. The approved increase is $172 per
semester. This would mean that the typical student would see an
increase in this fee of $430 per year ($172 + $172 + $86 (summer) = $430).
While the Purdue salary policy this year was no raises, most of you will
receive an increase in your salary to offset this fee incre |
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