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C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 这与用日本鹌鹑得到的实验结果[2]并不一致,日本鹌鹑蛋中的残留物水平似乎并没有受到孵化过程的影响,除了有一部分p,p′–DDT转化成p,p′–DDE以外。 英文
黑兹尔坦的结论似乎是根据对4枚孵化蛋蛋黄和5枚鲜蛋蛋黄中DDE水平的对比结果得到的。正如他在发表的文章中所述:表1中标有“蛋黄重量”的那一列实际上指的是蛋黄加上胚胎的重量。“蛋黄”中DDE平均浓度显著降低至原来的1/3.2,这只能说明蛋黄+胚胎的重量增加至2.6倍,因为胚胎会从蛋白中吸收物质。在黑兹尔坦的样品中,孵化蛋的全蛋DDE残留物(平均值为2.53 mg)比鲜蛋的全蛋DDE残留物(3.62 mg)略微少一些,但是这种差别在统计学上不是特别显著,而且无论如何也不能由此证... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 英文
(吕静 翻译;周江 审稿)
Two Types of Mountain Building
J. T. Wilson and K. Burke
Editor’s Note
This beautifully concise paper by geophysicists John Tuzo Wilson and Kevin Burke at the University of Toronto explains how different types of mountain features can be produced at subduction zones, where the convergence of oceanic a... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | plate is actively advancing, the subduction zone takes the form of coastal mountains as in Chile with a marginal trench which is pushed ahead of the continent5 (Fig. 1a, b), and for the case in which the oceanic plate is actively advancing, island arcs and trenches form off-shore as in East Asia with little disturbance... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | According to these arguments the active advance of North America over both the mantle and the Pacific Basin during the Mesozoic Era would explain why the Nevadan orogeny and the Cordillera have no counterparts on other North American coasts and took the form of a marginal trench and coastal mountains. 中文
On the other h... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | Where orogeny has produced island arcs the products of volcanism accumulate and become metamorphosed separately from, and without affecting, the sedimentary shelf deposits6. It has thus been logical to interpret the extensive and little altered fold belts of the Acadian, Appalachian, Antler, Sonoma and similar orogenie... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | The Mesozoic shoreline departs significantly from the present coast only in the vicinity of Oregon where an embayment is underlain by thin, possibly oceanic, crust26 and seems to be closed by the Cascade Mountains, marking a subduction zone resembling an island arc27,28. 中文
One possible corollary of the proposed Palaeo... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | Whittington, H. B., and Hughes, C. P., Phil. Trans. Roy. Soc., B, 263, 235 (1971).
Kistler, R. W., Evernden, J. F., and Shaw, M. R., Geol. Soc. Amer. Bull., 82, 853 (1971).
Smith, J. G., McKee, E. H., Tatlock, D. B., and Marvin, R. F., Geol. Soc. Amer. Bull., 82, 2933 (1971).
Zietz, I., Hearn, jun., B. C., Higgins, M. ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 英文
在第二种情况下,倘若有两个或两个以上的大洋板块从不同方向向静止的大陆俯冲,那么岛弧与海沟就可能同时在静止大陆的多侧边缘形成(图2b)。这样就可以解释为什么缅甸–印度尼西亚、菲律宾以及台湾–吕宋岛一线的岛弧能够从三面包围被认为是近乎静止不动的东南亚大陆板块了[1]。 英文
根据以上论述,用覆于地幔与太平洋海盆之上的北美大陆在中生代时期的主动向前推移即可解释为什么在北美的其他沿海地区没有出现内华达造山运动和科迪勒拉山系那样的情况,以及为什么会形成边缘海沟和海岸山脉。 英文
另一方面,有证据表明,古生代期间曾有几个造山运动同时发生于北美大陆上的不同海岸地区[7],这说明至少在从泥盆纪到三叠纪这段时期内,北美大陆是近于静止的。这一观点... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 英文
(齐红艳 翻译;孟庆任 审稿)
The Macroscopic Level of Quantum Mechanics
C. George et al.
Editor’s Note
Albert Einstein and other critics of quantum theory had long noted the difficulty of reconciling its description of the microscopic world—where it suggests particles often exist in a superposition of two or more states—with th... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | The formal side of the problem, however, which consists in establishing the consistency of the rules connecting the formalism of quantum mechanics with the concepts used in the account of macroscopic observation, still leaves scope for a presentation more in accordance with the conceptual simplicity of the actual situa... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | analysis to the case of a measuring apparatus, initially triggered off by an interaction of atomic duration with an atomic object, shows in a surprisingly simple way that its evolution in conforms to the “reduction” rule of quantum mechanics; this important conclusion follows directly from the mathematical structure of... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | Then the projections ρ0=P0ρ and ρc=Pcρ of the density supervector correspond, respectively, to the average distribution densities and the correlation amplitudes. Putting L00=P0LP0, L0c=P0LPc and so on, we obtain for ρ0 and ρc the coupled Liouville equations
The next step is to extract from these equations the asymptot... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | It has the form of an integral equation, showing how the asymptotic correlations build up by sequences of processes starting from the average situations through which the system passes in the course of time. 中文
We now introduce an asymptotic time evolution operator by writing in the form
The advantage of the represent... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | The expression for the superoperator of correlation creation C, which enters in the definition of Pa, is clearly unsymmetrical in time, and gives the projector Pa the expected bias towards a preferred direction of the time evolution. In fact, time inversion transforms Pa into a different projector , where the superoper... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | are contained in the complementary subspace orthogonal to the asymptotic one. That such a clean separation between the two aspects of the atomic system could be effected is an entirely unexpected property specific to the density supervector representation: it could never have been found by a study of the evolution of t... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | One further point should be mentioned. The theory gives us a simple criterion to decide whether the system shows the normal macroscopic behaviour described by thermodynamics. The superoperator of asymptotic time-evolution θ is closely related to a “collision superoperator” defined as the Laplace transform of the supero... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | Received January 28; revised March 20, 1972.
References:
George, C., Prigogine, I., and Rosenfeld, L., Det kgl. Danske Videnskabernes Selskab, mat.-fys. Meddelelser, 38, 12 (1972).
Prigogine, I., George, C., and Henin, F., Physica, 45, 418 (1969).
Balescu, R., and Brenig, L., Physica, 54, 504 (1971).
Prigogine, I., N... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 我们的目的是要找出关联性造成的长时效应,首先我们必须将我们的由哈密顿量H描述的系统与由H0描述的“模型”系统进行比较。在“模型”系统中,与关联性有关的相互作用能V被去掉,它们的关系可以由H=H0+V表示。H0的本征态在希尔伯特空间中形成了表象的一组完备正交基,据此,我们在超空间中构造一组类似的基矢:后者可以被分为两类超矢量——由成对的全等(或物理上等效的)本征态构成的超矢量和由成对的不同本征态构成的超矢量;它们分别属于超空间中的两个正交子空间,可用投影超算符P0和Pc来表征。因此,密度超矢量的投影算符ρ0=P0ρ和ρc=Pcρ分别对应于平均分布密度和关联的振幅。取L00=P0LP0,L0c=P0LPc等等,我们可以得到关于ρ0和ρc... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 英文
式(7)中超算符的显著特征是:根据上文中的定义,它也是一个意义扩展了(不包含自伴性质)的投影算符;此外,它在时间反演后保持不变:它定义了超空间中的一个时间对称的子空间,从任意给定的状态开始,该子空间中时间演化的渐近部分保持有限,表现出了在宏观尺度上所观测到的性质;而在原子时间尺度上出现的不规则涨落则被纳入与渐近子空间正交的互补子空间中。对于密度超矢量表象而言,能够实现原子系统两个方面之间的明确分离完全是一个出乎意料的特性:在希尔伯特空间中对系统演化进行研究是不可能得到这一结果的,因为只有通过超空间的形式才能阐释它。 英文
超算符是不可分解的:除密度超矢量外,不能将其他任何态矢量归于我们所定义的渐近状态。事实上,由式(4)可以看... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | MY earlier publications1 have reported the concept, theory, and development of an antenna to detect gravitational radiation. These antennae are well isolated from the local environment by acoustic and electromagnetic shielding but they do respond to sufficiently large local disturbances. Effects of the local environmen... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | The amplitudes of the noise pulses have a Rayleigh distribution, and their shapes vary widely. Analysis is simplified if all pulses have roughly the same shape, because then one parameter, the pulse height, will suffice for their classification. To shape the pulses properly a second stage of filtering is carried out af... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | classified by equation (1). 中文
A two dimensional space with NA and NB as coordinates is useful to calculate the number of chance coincidences for which the product NANB is equal to or smaller than some constant and for which neither NA nor NB exceeds some maximum value NS. is expression (1) plus the integral under the ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | decision is needed. 中文
Using a magnetic tape and a computer provides an independent procedure for data processing. The human element is only involved in the program preparation. A variety of thresholds and time delays can be applied to any stretch of data. The synchronous detector output with 0.5 s filter time constant... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | Because of the 5 s averaging it is expected that the pulse peak will be reached between 2 and 15 s after the threshold is crossed and only those coincidences are recorded which reach peaks within such an interval. This range of values is required because of noise and the initial conditions of charge on the capacitors o... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | The detectors are coupled to each other by the Earth and respond to sufficiently large seismic events. A number of seismometers were developed including a vertical axis accelerometer tuned to the detector frequency of 1,661 Hz, a three axis accelerometer covering frequencies near 100 Hz, and a two axis tilt meter. No s... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | responds. No significant correlations were observed with the gravitational radiation detector coincidences. 中文
There is additional evidence that the coincidences are not due to electromagnetic or seismic interactions. The gravitational radiation detector system input temperature has been measured by a noise generator. ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | A search was made for coincidences between a 1,661 Hz gravitational radiation detector and a 5,000 Hz mode of a second gravitational radiation detector, both at the Maryland site. No excess of coincidences above the chance rate was observed. Subsequent investigation showed that the 5,000 Hz mode was a bending mode and ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | I thank F. J. Dyson, V. Trimble, and G. R. Ringo for valuable discussions and D. J. Gretz and J. Peregrin for maintaining and operating the gravitational radiation detectors. This work was supported in part by NSF and in part by the Computer Science Center of the University of Maryland. 中文
(240, 28-30; 1972)
J. Weber: ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 英文
选择平均太阳日作为时间单位。考虑功率幅值分别为PA和PB的两个通道的给定符合计数。令NA和NB代表每天功率值达到或者超过PA和PB的平均次数,Δt代表:为了记录到一次符合计数,两个通道越过功率阈值的最大时间间隔。在有效实验时间M天的观测中,功率幅值达到或者超过规定值的偶然符合的预期次数ηAB为:
ηAB = 2NANBΔtM
(1)
为了利用公式(1),我们任意选择了一些数值,这些数值对通道A和B来说可能相同,也可能不相同。一个给定的等级包含所有满足下述条件的符合计数,即NA和NB都等于或者小于那些针对它们任意选择的数值。 英文
为了确定观测到的符合计数和偶然符合计数的差值是否对统计方法的细节敏感,我们采用了另一种分级方案。我... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 英文
图1是NANB≤10,000且NS≤1,000的所有符合计数结果。当阈值被超越且由于噪声的存在而被再次超越时,低强度的符合经常被多次计数。因此,直方图给出的符合计数是磁带记录的120天内真实符合计数的两倍左右。图1中所有数据都来源于计算机,而不是对打印列表人工检验的结果。 英文
值得注意的是:任一通道的时间延迟,尽管小到只有符合计数时间间隔Δt的两倍,也使得符合计数率下降到原来的2/5。对20秒的延迟,符合计数率下降到原来的1/10左右。这些未经人工处理的数据毫无疑问地表明,相隔1,000千米的引力辐射探测器受到了同一个源的激发。 英文
在我们根据图1确定这个源就是引力辐射之前,必须排除其他目前已知的干扰。这些干扰包括地震、电... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 我们认为已经可以毫无疑义地接受,在1,000千米基线两端的引力辐射探测器是由一个共同的源激发的。这是相互作用的结果,这个作用既不是地震或电磁,也不是来自宇宙线带电粒子。 英文
感谢戴森、特林布尔和林戈与我进行了有价值的讨论,还要感谢格雷茨和佩雷格林对引力辐射探测器的维护和操作。美国国家科学基金会和马里兰大学计算机科学中心都为这项工作提供了部分支持。 英文
(何钧 翻译;张元仲 审稿)
Problems Still with Scrapie Agent
Editor’s Note
In this leading article, Nature drew attention to other diseases with similar... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | not been possible to purify and concentrate the agent. This is generally regarded as one reason why many workers have failed to detect a specific immune response, for the “antigen” has been a more or less crude preparation of tissues from affected hosts. Such tissues presumably contain many antigens associated with the... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | The most exciting possibilities come from the work of Carp and associates, because they may not only provide a rapid assay but may also bridge the gap between scrapie-like diseases and multiple sclerosis. The confidence of their report, with its modest claims for the assay, rests on the finding of a consistent differen... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | this approach will not incur problems of dealing with effects merely due to tissue damage. 中文
In the case of the lymphocyte sensitization test it is to be hoped that the claim of Field and Shenton, that it “enables the presence of scrapie to be established within 8 days” rather than several months, will prove correct. ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | But even in these cases the difficulty remains because of the high sensitivity of their technique, which may be detecting antigens from unseen damage. Its value will only be established when it can be shown that there is a close correlation between the titre estimates of the conventional assay and this new one in a lar... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 这篇发表于《自然》杂志上的社论将人们的注意力吸引到了类似于瘙痒症的其他疾病,尤其是克罗伊茨费尔特-雅各布病上。继之而来的是人们在1986年认识到英国牛得的一种被称为牛海绵状脑病(译者注:俗称疯牛病)的疾病就相当于牛瘙痒症,这对当前的农业造成了广泛的影响。人们仅用5年时间就证实人类食用带有病毒的牛肉会有被感染的危险,因而欧洲的牛贸易在此后数年内遭到了重创。瘙痒症及其他疾病的病因被认为与一种存在于所有动物体内的蛋白质的遗传有关,该蛋白质被称为朊蛋白,据推测它能够以多种形式存在,其中至少有一种会凝结在神经细胞中,从而导致严重的脑炎甚至死亡。 英文
在研究引起瘙痒症、传染性水貂脑病、库鲁病和克罗伊茨费尔特–雅各布病这一类疾病的病原体时,总会... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 我们不能认为这些动物的脾脏从未长期暴露在任一产生于脑内的已改变的抗原中。如果最终发现这种方法只能检测作为病原体浓度指标的组织损伤,它仍是有用的,因为它能“对抗原决定结构的微小改变作出灵敏的反应”,而且与目前能够快速估计出损伤度的常用组织学方法相比,这种方法可以明确地检测到更精细的损伤度。采用这种方法对注射后4周内的脾进行时间序列研究也许能排除一些可能出现的继发反应,在4周之内病原体浓度会快速增加,而脑内损伤的明显症状还远未出现,或者说,与黑格和克拉克[3]发明的利用组织培养系的常规检测法相比,这种新方法更具优势。 英文
然而即便如此,困难仍然存在,因为这项技术的灵敏度很高,有可能检测到不可见损伤产生的抗原。只有在能证明这种新方法的测... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | CONTINENTS can be positioned in their earlier places on the Cainozoic globe by means of their rock magnetism; continents for which such data are lacking can be placed in their relative positions by removing the subsequently generated seafloor. On such a reconstructed globe for a particular time in the Cainozoic the dis... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | based solely on seafloor spreading data2. For palaeoclimates the advantage gained in the use of rock magnetism data first, but with reliance on seafloor data as well, lies in the greater assurance that continents are primarily positioned with respect to the pole. Moreover, no assumptions are made as to the fixity of an... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | Fig. 2. Mid-Oligocene weather patterns.
中文
Having made reconstructions for these Cainozoic intervals, we can deduce rough circulation patterns of surface currents in the world ocean, and, with less assurance, suggest resulting trends in global climates. In the late Eocene South Pacific, much of the equatorial segment... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | Circulation patterns during the early Oligocene differ in that the Indopacific is segmented, for the first time, by the northward motion of Australia–New Guinea. The Pacific consequently approximates its present equatorial width. Further, the circumpolar current encircles the globe in the Southern Ocean, and exchange b... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | upwind from cold currents are considered to be “dry”, as compared with the average conditions for that latitude. In these deductions we follow Lamb18, who suggests that on an ice-free globe the trade wind belts would be expanded poleward at the expense of the high-latitude westerlies. Monsoonal conditions must have exi... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | further suggested by widespread coals of Eocene age. 中文
An important climatic effect of the cooling of Oligocene surface waters was to restrict the high-latitude wet belts to latitudes below 60°, although atmospheric temperatures also dropped. Monsoonal regions of continents were probably restricted as well, primarily ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | today, and the consequences are seen in the still lower temperatures and precipitation rates. 中文
Feedback mechanisms arising from the existence of warm oceans may have contributed to more efffcient atmospheric transfer of heat energy away from the equatorial heat source as well, but the relative significance of these p... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | Sverdrup, H. U., Johnson, M. W., and Fleming, H. R., The Oceans (Prentice Hall, New York, 1942).
Wolfe, J. A., and Hopkins, D. M., in Tertiary Correlations and Climatic Changes in the Pacific, 67 (Eleventh Pacific Sci. Congr., Tokyo, 1967).
Schwarzbach, M., Z. Deutsch. Geol. Ges., 118, 33 (1968).
Tanai, T., J. Fac. Sci... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 在对新生代中某个特殊时期的全球大陆分布进行重建的基础上,从重要的岩石类型和动植物化石进行推断,就可以用大陆间真实的地理关系绘制出古气候分布图。大陆、次大陆在旋转坐标系中的位置以及它们相互之间的位置会影响海洋和大气的环流模式,从而在很大程度上决定了盛行气候的趋势。在本文中,我们将试着用半定量的方法建立一个模型,以模拟始新世后半期(距今4,000万年~4,800万年)和渐新世前半期(距今3,000万年~3,700万年)时地球上的气候,后一时期是气候发生明显变化的时期。 英文
为了解释全球的古气候,必须重建各大陆相对于地球旋转极的位置,因为纬度对气候有很大影响。在整个新生代,平均古地磁极很可能位于接近地球旋转极的位置,而古地磁极相对于地理... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 英文
我们对早第三纪(译者注:现称古近纪)时海面温度分布情况的推断显示了大陆上蒸发和降水的相关分布。当海洋中比较温暖的部分与相对较冷的空气接触时,最容易出现蒸发;而当湿润气团因为地面气团辐合或被地形阻挡而被迫上升时,则最易发生降水。现在,降水在赤道~北纬10度之间以及30度~50度之间锋面辐合带的附近最为丰富。降水还集中在沿大陆西海岸的40度~60度之间和东海岸的15度~30度之间。在始新世,降水丰沛是整个印度–太平洋西部边缘的主要特征,而且湿润带可能会延伸到比现在高很多的纬度,因为那时的表层水温较高。因而与较高的表层水温相邻近的大陆区域以及其下风方的大陆区域,在图1中被标记为“湿”。以此类推,与同一纬度的平均条件相比,在低表层水温... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 英文
(蔡则怡 翻译;李三忠 审稿)
Rapid Diagnosis of Scrapie in the Mouse
E. J. Field and B. K. Shenton
Editor’s Note
Scrapie is an ancient agricultural disease of sheep whose cause was unknown until the 1990s.Here two British scientists describe a means for the rapid diagnosis of the presence of scrapie by the use of infected mice.... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | migration of normal guinea-pig macrophages in an electric field (macrophage slowing factor (MSF)—which may be identical with macrophage inhibitory factor (MIF)). Our measurements have been carried out in a Zeiss cytopherometer and full experimental details have been given4. 中文
Guinea-pig blood lymphocytes were prepared... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | The scrapie brain and spleen with which the guinea-pigs were inoculated were titred out by inoculation into groups of 6 mice at dilutions of 10–1 through 10–7. The animals were observed for eight months and all clinical scrapie diagnoses were checked histologically. 中文
Guinea-pigs were immunized with either scrapie or ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | In the case of inoculation with scrapie brain, however, the difference may perhaps be attributed to morphological changes (especially astrocyte increase) in the inoculated material. Having established the quantitative difference in response to scrapie as opposed to normal tissue we used this method to titre out scrapie... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | Guinea-pigs were sensitized by injecting scrapie spleen at 10–1 to 10–6 and their lymphocytes tested for sensitization to scrapie brain and spleen (Table 3). A significant difference between sensitization to scrapie and normal spleen still exists at 10–5 (P<0.01) with spleen as antigen but barely with brain (2.1% diffe... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | neuronal and glial compartment by the method of Giorgi (unpublished) then, contrary to expectations based on the precocious glial hypertrophy, higher scrapie titre is associated with the neuronal rather than the glial fraction and it is in the former that particles with the size and structural characters postulated for... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 同样也给对照组动物注射了正常小鼠脑或脾的悬液,而这些正常小鼠又在数周前被注射过正常动物的脑悬液。5天后,我们通过心脏穿刺得到2 ml~3 ml血,并用灵敏和高度特异的巨噬细胞电泳迁移(MEM)法估测淋巴细胞对瘙痒症悬液和正常悬液的致敏程度[3]。这种方法的基本原理是已致敏的淋巴细胞会释放出一种能减慢正常豚鼠巨噬细胞在电场中迁移速度的蛋白(巨噬细胞致缓因子(MSF)——可能与巨噬细胞抑制因子(MIF)为同一分子)。我们在测量中使用了蔡司细胞电泳测量装置,全部实验细节都已公布[4]。 英文
豚鼠血淋巴细胞采用由库尔森和查默斯发明[5]并经过休斯和卡斯帕里改进[6]的方法获取。而正常豚鼠的巨噬细胞则是用肝素化的汉克氏平衡盐溶液从注射无菌液... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 英文
对于注射正常脑组织的动物,其淋巴细胞对瘙痒症脑或脾的致敏程度与其对正常脑或脾的致敏程度相比并无显著差异(尽管从总体情况来看前者的数值要大一些)。 英文
给豚鼠注射稀释10倍~106倍的瘙痒症脾组织使之致敏,然后检测它们的淋巴细胞对瘙痒症脑和脾的致敏程度(表3)。在用脾作为抗原时,淋巴细胞对瘙痒症脾和正常脾的致敏程度在稀释105倍时仍存在明显的差异(P<0.01),但在用脑作抗原时则只有很小的差异(差异为2.1%,P=0.05),这说明在稀释105倍时会出现明显的瘙痒症抗原性。 英文
对接种到实验豚鼠上的瘙痒症脑组织的滴度进行计算所得的结果是LD50=10–5.6。我们注意到在稀释106倍时有1/6的小鼠染上了瘙痒症,在稀释10... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | THE nature of the scrapie agent1,2 is of considerable interest especially as to whether it is a virus in the strict sense, or some replicating agent devoid of nucleic acid3,4, or indeed whether scrapie disease represents a transmissible progressive biochemical transformation of cellular membranes5,6. Thorough electron ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | A thorough and realistic search of comparable normal rat brain has not revealed similar particles though the vagaries of electron microscope sampling must constantly be borne in mind. The size of the particles is about that deduced from modern infectivity filtration experiments9. Moreover the size of central rod accord... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | process) affects, or at least reaches greater development within, neurones and that glial changes, even though they are more conspicuous, have the consequential character they are usually assigned in neuropathology. The present work illustrates the synergism of different disciplines in approaching the problem of slow i... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | Hadlow, W. J., discussion in Slow, Latent and Temperate Virus Infections, NINDB Monograph No. 2, 303 (1965).
Field, E. J., Int. Rev. Exp. Pathol., 8 (Acad. Press, New York and Canada, 1969).
Savage, R. D., and Field, E. J., Anim. Behav., 13, 443 (1965).
Sellinger, O. Z., Azcurra, J. M., Johnson, D. E., Ohlsson, W. G., ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 本文可以说明不同学科在解决慢性感染问题中的协同作用。 英文
表1.瘙痒症病原体活性的免疫滴定分析
* 读数的离散度为:2.5%的差异,对应于P<0.01。
在豚鼠的右足皮内接种浓度为10–1~10–4的患瘙痒症小鼠脑内神经元和胶质细胞的提取物(每次0.1 ml,相当于300 μg~0.3 μg蛋白质)。采用巨噬细胞电泳减慢法测量豚鼠淋巴细胞相对于10–1浓度的瘙痒症脑和脾以及正常脑和脾的致敏程度,并用减慢的巨噬细胞百分比来表示[17]。 英文
(毛晨晖 翻译;李素霞 审稿)
Problems of Predicting Earthquakes
T. Rikitake
Editor’s Note
The questions pos... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | This was the motivation for founding the Earthquake Research Institute (ERI), attached to the Tokyo Imperial University (now the University of Tokyo), in 1925. A number of outstanding physicists, engineers, geographers and geologists of the time were appointed to chairs at the institute, but they were almost all part-t... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | There was much to learn about earthquake phenomena in the early days of the ERI. Seismology in Japan was started off by professors who had been invited there from western countries in the years that followed 1868. After the violent Nobi earthquake of 1891, the Imperial Earthquake Investigation Committee was set up; it ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | The ERI’s impact during its first ten years was so remarkable that many new facts about earthquake phenomena were discovered. Probably the most flourishing period in the history of ERI was, however, the following five years in which intensive seismometric studies, electric and magnetic experiments and field studies and... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | associate professors, forty-nine research associates, eighty-eight technicians working in laboratories and workshops, and thirty-eight supporting members in the administrative sections. Of these, thirty-nine work at provincial observatories. 中文
Fig.1. Interior of the Nokogiriyama Observatory for crustal deformation, a... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | A long-term programme for research into the prediction of earthquakes, which followed the line of the blueprint, was actually launched in 1965 after much debate in the Science Council of Japan and the Geodetic Council, which is responsible for the coordination of geophysical observations in Japan. The Niigata earthquak... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | The observation of seismicity, certainly one of the most important items of the earthquake prediction programme, has also been stressed. Although relatively large earthquakes with a magnitude greater than 4 or so on the Gutenberg-Richter scale are to be monitored by a network organized by the Japan Meteorological Agenc... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | and government institutions; it actually functions as the headquarters for earthquake prediction. Whenever CCEP foresees the possibility of a destructive earthquake in a certain area, that area is earmarked as an area of intensified observations of a certain rank depending on the assessment of the danger. It has not as... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | To process the large amount of data observed over the Matsushiro area, the ERI hired many temporary staff, chiefly to analyse seismograms. About sixty non-regular members were working in the ERI at the peak of the Matsushiro activity. As it is a government agency it was not possible for the ERI to increase the number o... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | and night. It has been difficult for most professors in the ERI to work in their offices since then. A neighouring institute, the Microbiology Research Institute, has recently come in for similar treatments. 中文
It is really ridiculous that such a strike should have lasted more than two years. Research associates, techn... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | Kanto earthqwuake. The ERI would have played a most important part in conducting various observations there if it had been functioning normally. Although the ERI is doing some work in the area, taxpayers may well say that the ERI is not working properly. 中文
An intensification of earthquake prediction programmes is now ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 由于当时没有人知道如何去建造一座足以抵御目前可知的最严重地震的建筑,因此只能把办公楼建造得尽可能坚固。两台性能相同的地震仪分别被放置在地下室和楼顶上,实际上由它们测得的地震图是完全相同的。 英文
第二次世界大战以前,该研究所仅有30~40人,其中包括技术人员、杂务工和行政人员。在那个美好的年代没有本位主义,人们可以自由地进入任意一间实验室,使用任意一台仪器,只要当时没人在用。然而,近些年情况发生了变化,因为在大学校园的最北端又建成了一幢大约是原办公楼10倍大小的新建筑,目前在那里工作的人员已经达到了200人左右。在这样一个人与人之间了解不够多的大团体中,那种家庭气氛不可避免地消失了。 英文
白手起家
在地震研究所成立之初,人们对很多... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 英文
负责全国地球物理观测协调工作的日本学术会议和大地测量会议经过多次讨论后,根据该蓝图制定了一项关于地震预报研究的长期计划,并于1965年开始正式实施。1964年的新地震确实在一定程度上加速了该计划的启动。1968年,日本北部发生了十胜冲地震,并造成了严重的破坏。于是地震预报的重要性上升到了内阁级别,该项目的目标也因此而被设定为对地震进行尽可能有效的预报,而不是仅仅停留于收集地震预报所需的资料。 英文
地震预报项目涉及多个学科。首先,工作重点主要放在反复进行水准测量和三角测量以探查异常的地面形变。人们相信,地震的震级以及发生的时间在某种程度上可以通过异常的地壳运动进行预报,即覆盖面积越大,震级就越高。近年来,利用激光源进行远距离光... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 在警察的干涉下,这种疯狂的事件曾一度中止,但东京大学的校长并不愿意警察长期呆在学校里。警察刚一离开,研究所中的某些地方就又被闹事者霸占,并且昼夜都不离开。从那以后,地震研究所的大多数教授想要在自己的办公室里工作都很难。最近,附近的微生物研究所也遭遇了类似的事情。 英文
极其荒唐的是,这样的冲击居然已经持续了两年多。助理研究员和技术人员之类的普通员工可以绝对放心地在所内工作,外宾和其他大学的教授也可以非常自由地进入所内,并且地震研究所的所有地方观测站都在完全正常的状态下运行。需要强调的是,大多数地震研究所的员工并没有参与这场骚乱。尽管有些人宣称他们不会在一个由“不体面的教授”所管理的研究所工作,但地震研究所的每位工作人员都拿到了满额的... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | ONE of the characteristics of muscle research in Japan is the close personal contact and willing cooperation that exists among research workers. This pleasant atmosphere was the result of the paternal leadership of Professor H. Kumagai, who in 1955 invited young muscle scientists to join a research group in which enthu... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | elementary process of muscle contraction, namely the interaction of myosin, actin and ATP, does not require the presence of the Ca ion. 中文
Establishment of the Ca Theory
The wide recognition of the part played by the Ca ion is chiefly based on several findings1,2,7 reported between 1959 and 1961. First, it turned out t... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | At first sight it seems strange that the Ca ion was ignored for so long after the injection experiments mentioned above. An explanation may, however, be found in the report published in 1963 that the regulatory function of the Ca ion requires a corresponding protein system different from myosin and actin1,2,9. (It was ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | support for this idea has come from the work of Ishiwata and Fujime14 in Oosawa’s laboratory, which is based on the measurement of the flexibility of the actin-tropomyosin-troponin complex using quasielastic light scattering technique. 中文
Troponin is not a single protein but a complex of three components15,16. One comp... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | the experiments on injection of Ca ions into muscle fibres and those involving extracts of the protein system. The proposal that a “Ca-induced Ca-release mechanism” is at work in the sarcoplasmic reticulum2,21,22 is also based on experiments with skinned fibres. 中文
(240, 217-218; 1972)
Setsuro Ebashi: Department of Pha... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | Natori, R., J. Physiol. Soc. Japan (in Japanese), 11, 14 (1949); Natori, R., Jikeikai Med. J., 1, 119 (1954).
Podolsky, R. J., and Costantin, L. L., Fed. Proc., 23, 933 (1964).
Ford, L. E., and Podolsky, R. J., Science, 167, 58 (1970).
Endo, M., Tanaka, M., and Ogawa, Y., Nature, 228, 34 (1970).
钙离子与肌肉收缩
江桥节郎
编者按
在本文中... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | (后来,肯德里克–琼斯等人发现[10]:在软体动物的肌肉中,接受钙离子的位点位于肌球蛋白分子的内部;因此上述调控机制就会涉及一个有趣的系统发生问题。) 英文
这种蛋白质调节系统由原肌球蛋白和一种新发现的蛋白——肌钙蛋白组成,分布在肌动蛋白丝中,间距为38 nm~39 nm(图2和参考文献1、2)。原肌球蛋白是一种长约40 nm的纤维状蛋白,虽然贝利[12]早在1946年就分离出了这种蛋白,但直到约17年以后人们才把它的功能搞清楚:它负责介导钙离子对结合在肌动蛋白丝上的肌钙蛋白的影响。(这一新蛋白质系统的发现引导人们分离出了一些新的肌原纤维蛋白,如α–辅肌动蛋白、β–辅肌动蛋白和M蛋白,这些蛋白都与细肌丝和粗肌丝的结构排布有关,它们与... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | million years) mixing due to convection. This would, for a period of about ten million years, lead to a lower temperature at the surface of the Sun, and fewer neutrinos coming from it. The neutrino problem has since been solved in another way: some of the neutrinos change their type on the way from the solar core to th... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | (or, to be more precise, free function) of the theory. Varying l causes the relatively diffuse outer layers of the model to readjust so that the heat can still be transported. This has little effect on the structure of the central regions so L is hardly affected. Broadly speaking, therefore, l determines Te, but in pra... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | of the solar core and find a process which may lead to intermittent mixing; indeed Fowler17 has pointed out that such mixing may be even more efficient at reducing Fv. 中文
Instability of the Solar Core
In the core of a main sequence star the thermonuclear generation of energy has negligible effect on the Schwarzschild c... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | where u is the fluid velocity and w its vertical component; p, ρ, T are pressure, density and temperature, K is the radiative conductivity 4acT3/3κρ, Cp is the specific heat at constant pressure, β is the superadiabatic temperature gradient and g is the gravitational acceleration. In these equations unprimed variables ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | the leading term of either q1 or q2 is real and positive, and provided this exceeds the small second term the fluid layer is unstable to direct convective motions. This criterion was obtained by Ledoux21. But we pointed out above that solar models are stable to even the Schwarzschild criterion: , and the g modes are os... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | The existence of the composition gradients is also responsible for the secular mode whose growth rate is given by equation (10). Imagine, for example, a fluid element to experience a positive temperature fluctuation. It will rise to find a new hydrostatic equilibrium position which, because condition (11) is not satisf... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | An approximate stability criterion for the Sun was derived by evaluating the work integral25 for nonradial modes using the adiabatic eigenfunction for the fundamental g mode associated with the surface harmonic with l=2 published by Cowling26 for the polytrope of index 3, and making the Boussinesq approximation in calc... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | increased by a factor of about 5 in a polytrope model and if the temperature were to stay constant the rate of the 3He–3He reaction would increase by a factor of 25. The consequent increased heat flux can no longer be stably transported by radiation alone, the Schwarzschild criterion for stability is violated and a mec... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | expands almost adiabatically and cools. This causes a reduction in the effective temperature and surface luminosity. Meanwhile, as the 3He abundance relaxes to equilibrium the temperature sensitivity of the energy generation is reduced and the convective core disappears. The bulk of the envelope has not yet had time to... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | mixing phases is decreasing. In the next section we argue that it is now about 2.5×108 yr. 中文
To simulate the gross effects of earlier mixing a solar model was evolved for 4.45×109 yr with a core of mass mc artificially mixed. Normal evolution was allowed for a further 2.5×108 yr, then the entropy and chemical composit... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | Fig. 1. Time variations of the surface luminosity of the Sun, in units of its present value, and of the neutrino fluxes Fvp, Fv7 and Fv8 measured in s.n.u. (The neutrino capture cross-sections were taken from Bahcall36.) The first minimum in Fv8 occurs soon after the convective core begins to recede, the second when th... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | the model) is negligible, but it is unlikely that the sum of Fvp and Fv7 can be reduced appreciably below about 0.7 s.n.u. 中文
Solar Chronology and the Terrestrial Climate
The most recent of the Earth’s major ice ages were separated by approximately 2.5×108 yr (ref. 37) which is of the same order as our rough estimate o... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | It is also necessary to ask whether the 5% drop in L is enough to produce an ice age. Theoretical discussions7,40,45 suggest it is, but because these are deficient at least so far as they do not predict the long term stability of the climate, they cannot be relied on. The supporting empirical evidence is that the relat... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | influences, such as the changes in the geomagnetic field, dominate52. Alternatively one might expect to unravel a direct record of the cosmic ray flux by analysing nuclear tracks in rocks, but this has not yet been possible53. 中文
We thank Professor N. H. Baker, Dr. A. Delany, Mr. D. C. Heggie, Professor K. H. Prenderga... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | Shaviv, G., and Salpeter, E. E., Astrophys. J., 165, 171 (1971).
Gough, D. O., and Spiegel, E. A., Comm. Astrophys. Space Phys., 4 (1972).
Fowler, W. A., Nature, 238, 24 (1972).
Eddington, A. S., The Internal Constitution of the Stars (Cambridge University Press, 1926).
Spiegel, E. A., and Veronis, G., Astrophys. J., 1... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | Milankovitch, M., Théorie Mathématique des Phénomènes Thermiques Produits par la Radiation Solaire (Gauthier-Villars, Paris, 1920).
Emiliani, C., J. Geol., 63, 538 (1955).
van Woerkom, A. J. J., Climatic Change (edit. by Shapley), 147 (Harvard, Mass., 1953).
van den Heuvel, E. P. J., Geophys. J. Roy. Astron. Soc., 11, ... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 在本文中我们考虑了太阳核心的稳定性并且发现了一个会导致间歇性混合的过程;实际上福勒[17]已经指出过这种混合可能对降低Fv值更为有效。 英文
太阳核心的不稳定性
在一颗主序星的核心,热核反应产能对史瓦西判据的影响可以忽略不计。这是因为产能的时标要远大于对流模式增长的时间,所以当考虑对流模式的时候通常忽略产能。但是能量产生可能会使重力模式不稳定,就像爱丁顿[18]认为在造父变星内部脉动有可能会被驱动一样。我们考虑一个极其简化的模型:一层简单的平行分层液体,厚度为d,它内部每单位质量的产能率为ε。我们暂且假设主要的核反应只有ppI链中的p(p, β+ν)D(p, γ)3He和3He(3He, 2p)4He反应,其产能率分别为ε11和ε3... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 在核心外,唯一存在的非绝热效应就是辐射阻尼,奥雷[23]曾估计早型星包层的阻尼作用远远超过了下层(在半对流区内)的激发,这主要是因为扰动的幅度随半径增加得很快。但是,在太阳中相对较深的外对流区却存在一个重要的不同。当时,正如在p模式的情况一样[24],辐射热传递倾向于使振动失去稳定性,并且在任何情况下振幅都会随着半径而降低。此外,我们可以预期在此区域中与非稳定直接对流运动之间的相互作用将破坏该运动与核心内运动之间可能存在的任意相关。值得注意的是:假如辐射阻尼足以使等式(9)和(10)中的α有效值为正的话,那么长期模式必然是稳定的。 英文
太阳的一个近似稳定性判据可以通过以下方式导出:用基本g模式下的绝热本征函数,结合考林[26]针对... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 我们现在正在研究的是一个更实际太阳模型中的非径向模式的稳定性。因为太阳目前的光度大约比它刚进入主序阶段时高了40%,所以它会更快地演化。因此,只要结构的变化不足以大到使稳定性判据发生显著的改变,那么两个相继的混合期之间的时间间隔就会缩短。在下一节中我们将论证这个时间段的长度大致为2.5×108年。 英文
为了模拟出更早期混合的总效应,我们让一个具有人为混合过的质量为mc的核心的太阳模型演化4.45×109年。再继续进行正常的演化2.5×108年,然后核心区的熵和化学组成被迅速混合,随后再按正常演化继续进行。我们发现超绝热的核心在经过突然混合之后确实扩展了,虽然它还没有扩展到mc。结果产生的运动速度足以把7Be在比电子俘获的半减期更短... | 400套付费套装书 |
C:\Users\yuan\Documents\400套付费套装书\04-100套\epub\0307. 《自然》百年科学经典(英汉对照版)(第五卷)(1966-1972).epub | .epub | 16,876,645 | 2025-09-26T19:07:54.356078 | 因为全年总日照能量的波动幅度通常只有大约1%,所以我们至少可以认为5%的浮动足以诱发一次大的冰期的观点有一定道理。 英文
接受这一理论框架将导致我们预期:更新世的开始时间接近于距今大约3×106年前的光度极小值时期,那时中纬度地区已开始进入冰期[50](图1)。L在距今大约4×106年前开始下降,伴随着的是预期的南极冰期的开始[51]。由于更新世的开始时间没有达到太阳的开尔文-亥姆霍兹时间,因此太阳到现在还没有达到热平衡。这至少可以部分地解释在中微子流量理论估计值和戴维斯及其合作者测量出的上限值之间存在的差异。 英文
在核心被混合之后,太阳的演化在赫罗图上暂时变为反向,包层对流区变得更加活跃,太阳活动性和太阳风的强度可能也会增加。因... | 400套付费套装书 |
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