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156. Whereas in earlier experiments homograft rejection was frequently mistaken for tumor-specific resistance, recent experiments which were performed on inbred mice, under conditions excluding, as far as possible, genetic differences between host and tumor, may point to the existence of a true tumor-specific resistance.

157. Our discussions to this point have been confined to a rather restricted class of functions, namely, those described by linear differential equations. However important such functions may be, a computer system incapable of handling nonlinear func­tions is severely restricted in the range of applications.

158. Fairly intensive alloy studies are under way on all four refractory metals, and a considerably large number of promising alloys have already evolved. While few of these have as yet achieved commercial status, many have advanced to at least the point of pilot production or advanced laboratory scale-up.

159. On the other hand, neither myelography, nor even sur­gery can adequately differentiate normal disks from degenerated disks in patients who complain of back and leg pain. Myclogra­phy adds little or no information to plain lumbosacral x-rays so far as degenerative disk disease is concerned.

160. Nature of Transferable Pyrogen. In order to determine whether the pyrogen transferred ill the above experiments con­sisted primarily of the originally injected endotoxin or of newly formed endogenous pyrogen, its fever-producing effect was com­pared in normal and endotoxin-tolerant recipients.

161. As far as the measurement of range-rate is concerned, the total fluctuation at 400 mc/s will be small compared with the required tolerance of 1 m/sec.

162. To investigate whether inagglutinability of virustreated erythrocytes was due to the modification of receptors with conse­quent lach of adsorption of hemagglutinin or due to failure of red cells with attached virus to form characteristic agglutination pat­terns, experiments were done to determine if test virus hemagglu­tinin adsorbed to the theated cells.

163. The results obtained with the urea clearance test are pre­sented in the last line of Table IV. The poisoned mice retain about three times as much urea as normal mice, thereby indicating a suppressed kidney function. Retention of 76.3 per cent neglects the nitrogen that accumulates above control values in the blood and intenstines.

164. As far as the major planets are concerned. Mercury is the only one with bound rotation. I agree with the reduced figure of

137,000 miles for the orbital radius of a stationary satellite given,y your correspondent. This, however, is still as high as 88 times he radius of the planet, and my conclusion that it would be too far

out to be of practical value for communication purposes still holds.

165. Although the values for total lipid are of limited accura­cy, they nevertheless tend to indicate that esterified cholesterol and phospholipid probably are the only lipids present in signifi­cant concentration among the low density products. A small amount of lipid unaccounted for in the low density products from the human serum may represent released triglyceride.

166. Our age is often called the age of specialization. It might be more aptly called the age of ultra-specialization, for it is no longer sufficient for the scientist to specialize in one science, such as geology, metallurgy, chemistry, and so on. Even within this limited sphere of technical knowledge he must choose a narrow path if he is to reach its limit.

167. Additional studies on the sites of RNA synthesis in NDV-infected cells were carried out with tritiated cytidine. The expe­rimental procedures used were identical with those just described, with one exception: following fixation, cells were digested with DNAase, 30° g per ml of PBS, for 1 hour at 37° C. The cells were then refixed in acetic alcohol, dried, and processed for autoradio-graphs.

168. As in any endocrine disease, the diagnosis should be con­firmed by proof that the gland is secreting aldosterone in excess. For this purpose the best method to date consists of measuring secretory rates by estimating dilution of radioactive aldosterone in body fluids. However, the method is not readily available. In contrast, urinary excretion of aldosterone and its metabolites may be determined by a number of practical techniques.

169. Although humoral hemostatic defects may appear from time to time after acute hemolytic reactions involving canine anti-A, it is apparent that the physiologically most significant and consistent abnormality is that due to thrombocytopenia. Such a reaction, occurring at the time of experimental surgery can lead to a marked increase in blood loss, and at times, loss of animals.

170. Another striking and rather frequent exception from the criteria characterizing cancers is represented by basalcell carci­nomas of the skin, which may develop following an occupational or environmental exposure to sunlight, coal tar, and arsenicals. Basal-cell cancers of the skin do not produce metastases and there­by lack one of the most important properties of malignant growths.

171. Our experience suggests that the presence of a bruit is strong evidence of a partially open but stenosed internal carotid artery; and subsequent arteriograms usually support this opin­ion. The absence of a bruit, despite transient episodes or a persis­tent neurologic defect, suggests most frequently a complete occlu­sion. Again, this has been supported by arteriography.

172. Evidence of the altered responsiveness persisted through­out a period in which spontaneous paroxysmal activity was aboli­shed and self-re-excitation, to judge by the unit record, was ab­sent. By excluding reverberating impulses as the basis for the long lasting change in cellular behavior the isolation experiment made it necessary to search for structural alterations.

173. These findings indicate that glucose is incorporated into glycogen as an intact unit - i.e., with little or no cleavage of the carbon chain. This view on the mechanism of the conversion of glucose to liver glycogen is fully borne out by our demonstration of Identical recoveries of C14 in glycogen when liver slices were incubated with glucose-1-C14, -6-C14, and -E-C14.

174. In the present article we report the results obtained by using ferritinas a tracer to investigate glome-rular permeability in rats with proteinuria induced by PA treatment. The findings confirm the conclusions drawn and support the assumptions for­mulated in our previous paper. In addition, they provide new in­formation about certain morphological and physiological as­pects of the nephrotic syndrome.

175. Proceeding on the premise that the opalescence produced in serum by streptococcal extracts migth be due to low density lipids or lipid-protein complexes liberated from their normal as­sociations with serum lipoproteins, an experiment was underta­ken to determine whether such products could be separated from extract-treated sera by ultracentrifugal flotation at normal serum density.

176. These facets of the vasomotor transfer of heat have been

recognized for many years and thermal conductivity measure­ments have been used mainly as indices of blood flow rather than absolute measurement of blood flow. For example, Hertzman et al making estimates of both local tissue perfusion and thermal conductance found these two correlated well with each other but not in a one-to-one ratio.

177. A large computer can easily keep thirty or forty pro­grammers busy. Most of the senior programmers should be mathe­matical graduates, at any rate when the work is scientific rather then commercial. Some of them should be specialists in the branch of mathematics known as numerical analysis, while others should, if possible, have had previous experience in the particular field of science and technology from which the problems arise.

178. The transistors and diode specified are about the least expensive types on the market. Virtually any generalpurpose tran­sistors and diodes should work as well, if they are more readily available. C10 and C11, as mentioned, extend the upper frequency limit and maintain amplitude at this limit. Their values may have to be altered somewhat for different transistors, even of the type

ecommended.

179. In a supplementary test in which a sample of the same serum was incubated with the extract in a final dilution of 1: 10 instead of 1: 100, the divergence at pH 6.0 was even more pro­nounced. Cholesterol release in this case was essentially com­plete (33.1 mg per cent) after 1 hour of incubation, whereas, the opalescence produced amounted to only 0.30 optical density units, as compared to 0.5 for the corresponding mixture with the more dilute extract.

180. The guidance employed during the early powered flight of a space vehicle is referred to as injection, boost or ascent guid­ance. The techniques are almost the same as those used in the guidance of ballistic missiles and they are not described in this paper. Instead, the correction of space trajectories by small im­pulse-type manoeuvres is discussed, since injection guidance alone

would not usually be sufficiently accurate for advanced space

nissions.

181. Why are human beings born in a state so immature that it takes 8 to 10 months before the human infant can even crawl, and another 4 to 6 months before he can walk and talk? That a good many years will elapse before the human child will cease to de­pend upon others for his very survival constitutes yet another evi­dence of the fact that man is born and remains more immature for a longer period than any other animal.

182. Audio current through the coil varies the magnetic flux in the gap and causes the disk to vibrate and produce sound. The operating principle is much the same as that of the magnetic head­phone, although the physical construction is somewhat different. The variable-reluctance headphone gets its name from the chang­es in reluctance of the magnetic path as the metal disk vibrates. Only one manufacturer currently produces a headset of this type.

183. The objective of the studies which are the subject of this report was to determine whether young mice of inbred strains predisposed to a high incidence of spontaneous leukemia charac­teristically manifested an immunologie defect in their RES which conferred upon them, concomitantly, a unique susceptibility to experimental infection, or whether mice destined to manifest leu­kemia were characterized by an initial hyperactivity of the RES which correlated with the occurrence of leukemia in later life.

184. The operation of much of the TIROS I instrumentation is subject to ground control. Thus, a means is available to deter­mine from the ground the total instrumentation energy require­ments in a given orbit. During orbits in which ground illumina­tion is unsatisfactory for taking television pictures or the satellite is out of communication range of the two ground stations, little or no equipment was programmed and the major power drain was the continuous load.

185. Transducers commonly in use today utilize magneto­striction, or piezoelectricity. The former causes a slight variation in the length of a metal rod due to an alternating magnetic field in the direction of the axis of the rod. The latter is liberally pressure electricity which utilizes the property of a crystal to generate a voltage when mechanical force is applied, and conversely pro­duces a mechanical force by expanding or contracting when a voltage is applied.

186. In any case, the presently unknown materials constitute only a small portion of the urinary metabolites of N-2-fluoreny-lacetamide, although the elucidation of their nature and struc­ture is a problem of fundamental interest. In addition, some of the unknown compounds could be derived from the breakdown of carcinogen-protein complexes so that a knowledge of their com­position may yield some important clue as to the nature of the carcinogen protein interaction.

187. The process of arriving at the correct frequency is not completely random, since the magnitudes of the capacitor dis­charges become progressively smaller as the correct oscillator frequency is approached. The speed of correction depends on the rate at which the switch operates.

Once the system has arrived at the correct frequency, the AFC loop can be opened or the r—f signal can be removed without changing the oscillator frequency.

188. In Table II are recorded, together with the observations on coplement titers and antigen clearance, the incidence of the two major lesions found in hypersensitivity of the serum sickness type. Since in the present experiment observations were made only at 8,12 and 16 hours after injection of immune precipitates, the prompt reduction in hemolytic complement titers following BGG precipitates was not encountered and no difference in the complement titers was observed in the two groups of animals.

189. To build the transmitter, first collect three pieces of card­board tubing each about 12 inches long. The two larger pieces should be about 1 '/2 inches, respectively, in diameter so that the smaller one will telescope snugly into the larger one. The third piece of tubing should be about 5/8 inch in diameter so it can ac­commodate a flashlight bulb. The diameters of the two larger tubes are not too important althougt the largest should be big enough to talk into comfortably.

190. Transferable pyrogen was readily detected in the serum of leucopenic rabbits with endotoxin fever, provided a sufficient volume of serum was used in the passive transfer test. The febrile responses of normal recipients to intravenous injections of 25 ml aliquots are shown in Fig. 1. It will be noted that the resulting fever curves exhibit the relatively short latent period, the peak within 60 minutes, and the rapid defervescence characteristic of the febrile reaction to both leucocytic and serum endogenous py­rogen.

191. The LD₅₀ for mice of a series of endotoxin preparations containing different amounts of bound lipid appear in Table I. These findings, which present a more extensive series of data than we have reported previously, make it evident that lipid content does not bear any relationship to toxicity, as measured by lethality for mice. All preparations were potent and the distribution of LD₅₀ values was about what would be expected in the same number of replicante determinations on the preparation with an average LD₅₀ of 0.25 mg.

192. Reincubation with fresh enzyme resulted in the libera­tion of only small additional amounts of ether-extractable mate-rial. It is possible that the products formed inhibited the sulfa-tase. This point requires further investigation.

193. In any event the experiment of Chow serves to demon­strate that the material basis of the engram or durable memory trace is not likely to be revealed by the techniques of electrophysi-ology. No one will be surprised by this conclusion. The neural history of past events survives such cerebral holocausts as major convulsions, electroshock, trauma and concussion and deep an­esthesia — all things which should interfere with anything depen­dent upon continuous electrical activity. For this reason most workers have tended to think more in terms of morphological or chemical alterations.

194. Homolytic reactions due to canine anti-E incompatibili­ty have, in general, been somewhat milder than those due to anti-A in the limited number of instances observed. Low levels ofhe-moglobinemia have been encountered, and the bulk of the incompatible cells have been destroyed promptly.

195. In vitro applied endotoxin had no effect on glycocorti-coid output. A highly purified lipopolysaccharide derived from E coil was added to the medium in which normal glands were incu­bated mid the quantity of corticoid secreted was the same as that found under control conditions. This finding may be interpreted in two ways. Either the large entodotoxin molecule is unable to reach critical sites within the adrenal gland except, perhaps, in vivo via the blood stream, or else endotoxins alter adrenal func­tion indirectly and, hence, fail to influence directly glandular activity in vitro.

196. Electron microscopical studies have shown that the mas­sive proteinuria of the «pure» or «uncomplicated» nephrotic syn­drome is regularly associated with glomerular changes which affect the visceral epithelium and characteristically consist of a reduction or disappearance of the epithelial foot processes and of the intervening slits. This association, described originally in nephrotic children, has been, repeatedly confirmed in humans as well as in aminonucleoside nephrotic rats.

197. When you switch on an electric light you send a continu­ous flow of electricity through the wire to the bulb which remains lit until you switch it off. Suppose I could see the light and you wished to signal to me a particular number; you could do this by switching the light on and off. You might flash the light on and off as many times as necessary so that when I received the signal I could count the number of flashes. Therefore, to speed up the operations we should try to devise a system of abbreviation, or a code. This is precisely what the computer designers have suc­ceeded in doing.

198. Nevertheless both these processes act through the same neural pathways available to physiological stimulations. In the economy of nature it seems possible that the alterations in physi­ology, structure and chemistry seen in these simplified models differ from those in behavioral learning in degree but not neces­sarily in kind. At least they provide something to look at and to work with. Ultimately they will need to be related to the paramet­ric aspects of behavior disclosed by experimental psychology.

199. The design of a pulser for short pulse durations with substantially rectangular pulse shape requires the use of high-frequency circuit techniques since frequencies as high as 6° to 100 Mc/sec contribute to the pulse shape and the effects of stray ca­pacitances and inductances become serious.

200. For pulses which are definitely not rectangular, the ef­fective or equivalent pulse duration is either the time measured at some fraction of the maximum pulse amplitude that is significant to the particular application, or the time corresponding to a rect­angular equivalent of the pulse in question.

Раздел 2. УПРАЖНЕНИЯ НА ГРАММАТИЧЕСКИЕ ТРУДНОСТИ ПЕРЕВОДА

(Псевдопростые грамматические формы)

1. After the 1242-nd orbit on November 23, 1962, the com­mand channel ceased responding.

2. Superposition of the falling regions of these curves shows the gain to be independent of rs.

3. In the chapter on experimental techniques, we are given a good insight into many of the special problems that have to be solved.

4. The neutron may be considered in fact as being exposed to a time-dependent electric field.

5. On the basis of the product being a single isomer, the inter­mediate radical appears to react with iodine.

6. Britain's greatest single source of wealth is coal; it was this abundance of fuel which made it possible for her to take full ad­vantage of the industrial revolution.

7. It was only in 1781 that Emerson invented the process of direct fusion of the metals to produce a copper — zinc alloy we call brass.

8. The refractive index of amorphous selenium at a wavelength of 2.5 microns has been reported to be 2.46 or 2.44 by different authors.

9. However, the hypothesis of Siekevitz and Potter has been criticized on the grounds that AMP did not stimulate oxygen con­sumption as quickly as did ADP.

10. There is one important factor to be considered when a phase discriminator is used.

11. The equal spacing between components appears to make double flip-flops possible in most configurations.

12. They succeeded in obtaining good results working with quicksilver, it being known to be a very dangerous metal.

13. Project Telstar was planned from the first as being prima­rily a communications experiment.

14. The Boltzmann expressions for the transition probabili­ties are shown to have been applied under conditions for which they are not valid.

упражнения

15. It is desirable that the output signal should be a linear function of the input signal; any deviation from linearity is called distortion and is highly undesirable.

16. There have been rumours that more efficient carburators have been invented which are said to have increased the gazoline milage of automobiles by as much as 100 per cent.

17. The effect is highly dependent on frequency with the lower frequencies showing less noise.

18. Many proposals for changing the traditional methods of storing and searching for information have been made in the last decade, and some of these have already proved to be of consider­able practical value.

19. From what has been said so far, one might think that alter­nating current has little advantage over a direct current.

20. The atomic bomb explosion may blow a hole in the ocean a mile in diameter, the size depending on the amount of plutoni-um used in the bomb.

21. The best compromise is to select a low-coefficient fixed inductance.

22. It should be stated that we are assuming throughout this chapter that the primary condition that the system be stable is already satisfied.

23. The larger the screen of a television receiver, the more light must it emit if the picture on it is to appear satisfactorily bright.

24. Such fluctuations, being sensitive to the exact location of channel boundaries, would not be expected to reproduce in suc­cessive determinations.

25. Working under hard conditions were all the early students of this new field of electronics.

26. Bohr'stheory of atomic structure turned out to be extreme­ly fruitful in the explanation of various properties of atoms and molecules.

27. On close examination of a piece of granite we find it to be composed of several kinds of minerals having different degrees of hardness, different colours, and different properties in general.

28. As radio waves travel away from their point of origin, they become attenuated as a result of spreading out due to energy be­ing lost in travel.

29. This value is subject to systematic errors, the most impor­tant one reflecting our lack of knowledge of the energy spectrum.

30. A gram of water is proved to change exactly to a gram of ice when freezing and to a gram of water vapour when evaporating.

31. The material damping is considered in a manner which seems to be as exact as it can be without the use of nonlinear equations.

32. Hardness and tensile strenght tests are shown to be rather indirect attempts to measure the strenght of the bonds existing between the atoms of the metal.

33. Metals known to exist in more than one crystallographic form are cobalt, cerium, tin, manganese, chromium, thallium.

34. Should extreme gain stability be required, it can be achieved without degrading the noise figure.

35. Since the optical-model potential cannot be expected to take into account all interactions of the neutron with the nucleus an explanation along conservative of low-energy nuclear physics may turn out to be adequate.

36. Direct calculation of the position in a square well or oscil­lator potential is not accurate, absolute level positions being most sensitive to the details of initial assumptions.

37. The present era, which is distinguished by the utilization of metals in enormous quantities, may be said to have begun in 1860.

38. The original signal is reconstituted thereby, with the noise impulses «smeared».

39. Many proposals for changing the traditional methods of storing and searching for information have been made in the last decade, and some of these have already proved to be of consider­able practical value.

40. Perhaps on the basis of this notion most of the recent effort expended in attempting to prove existing tables of these factors has been limited to using better atomic wave functions.

41. The occurance of metals in the earth's crust is unequal, some of them being plentiful, the other existing only in small quan­tities.

42. If machining is necessary, dust created must not be al­lowed to excape into the plant atmosphere even in small amounts.

43. Unless these two particles scatter coherently in «hard» interactions, the small deuteron binding energy should not be expected to keep them together.

44. The curves of Figs. 15 and 16 show a much smaller rate of change of gain with pump voltage than do those of Fig. 8.

45. The moment a flame comes near the gas in the mines, the gas is sure to explode. If it does explode, it will kill every one in that part of the mine.

46. Our preliminary results do not suggest that caloric restric­tion is apt to provide a very profound increase in life span of mice bearing LI210 leukemia.

47. Since the barometer measures the pressure of the at­mosphere, the greater the elevation, the lower the barometer reading.

48. In the lower latitudes, the down and dusk periods will last about two hours.

49. It is true, however, as Wilkinson pointed out, that fast transitions are more likely to have been abserved than slow ones.

50. Although the structures proposed may not have been es­tablished with complete certainty, all the known facts, physical and chemical, fit beautifully this ingenious interpretation.

51. With the slots alternately inclined the phase is reversed by 180° and this enables the slot spacing to be less than a free-space wavelength.

52. It is the gravitation that makes the satellites move round the earth.

53. The electrical manufacturing industry would be helped very considerably if more of the insulation manufacturers gave reliable technical information on their products.

54. A rough estimate of the rate of cooling and growth of the solid crust of our globe indicates that the cooling process must have begun several billion years ago.

55. It was important that the satellite not be dependent upon orientation relative to the sun or the earth.

56. These experiments prove that it is physically possible for the ground ice of Alaska to have been formed by a process of segregation.

57. If a single drop of water were magnified to the size of the earth, each molecule contained in it would be no larger than a football.

58. He believed the results of this test to have been plotted in

the diagram.

59. Associated with the slow creep of metals at elevated tem­peratures is another general phenomenon in metals known as re­laxation.

60. Also, in order that the capacitance divider ratio shall be independant of frequency, C2 must have no appreciable induc­tance.

61. The engineer wants the workers to use soft rubber for elec­trical insulation.

62. It is among the naturally occuring minerals that we find the most beautiful examples of crystals.

63. We know physical chages to be caused by heat.

64. One should know that the electric cell is a device for con­verting chemical energy into electrical one.

65. When solid black is being transmitted, all of the styli will be marking virtually all of the time.

66. It is usual that the slower the rate of cristallization, the more perfect are the resulting crystals.

67. The positive particle in the nucleus of the atom was given the name of «proton».

68. The atomic scattering factor or form factor may be thought of as being a measure of the scattering due to the individual atoms.

69. Had we informed proper agencies interested in building such a machine we should have received their necessary assis­tance.

70. In modern aviation greater and greater speeds are being attained, entailing, however, a substantial increase in air resis­tance.

71. In the following the analysis of symmetrically-loaded stairs with both ends fixed is described.

72. Essentially, in this model the crystal is assumed to be en­tirely ionic with no exchange between charge clouds of adjacent

ions.

73. Infra-red rays being invisible to us, photographic films and plates are made to-day which are sensitive to them.

74. There is a certain amount of interaction between the tuning and loading functions, but it is not excessive at normal values of Q-factor.

75. However plentiful the ore may be the extraction of a metal will not be profitable unless it is sufficiently suitable for some purpose to be sold at a price that will pay for extraction.

76. The input signal was taken to be a fast wave at the cyclo­tron frequency, which meant that all the electrons had orbit radi­us s and the same time phase of rotation, assumed to be zero.

77. Never before has there been any device so versatile and efficient in handling electricity as the electron tube.

78. For other types of signals the carrier level may have to be increased.

79. The neutron may be considered in fact as being exposed to a time-dependent electric field.

80. At higher energies electric dipole radiation can be expec­ted to give rise to D state in the continuum.

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