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Herein, we describe a new semisynthetic strategy of a post-translationally modified protein in which the middle region is glycosylated. We designed a single-plasmid coding for a fusion polypeptide, which can provide both an N-terminal α-thioester and a C-terminal cysteine peptide of a target glycoprotein by using chemical-cleavage and activation methods. The use of these resultant peptide derivatives resulted in the successful synthesis of N-glycosylated-interleukin 13. more...

It has been common in the chopper inelastic neutron scattering experiments using a pulsed source to assume a certain experimental layout, such as the flight paths, chopper opening time and sample size etc., and calculate the expected counting rate together with the energy and momentum transfers and their widths (ϵ, Q, Δϵ, ΔQ). We start here, on the contrary, by setting ϵ, Q, Δϵ, and ΔQ to some predefined values, and then find out the instrument parameters that cam yield the optimum counting rate. Two main cases were studied: (1) the case when the sizes of moderator, sample and detector width were taken to be adjustable to make the counting rate optimum; (2) taking the moderator width fixed, the optimum sizes of sample and detector were calculated. In both cases, the expected characteristics of the IPNS pulsed neutron source were assumed. more...

Like many of his American counterparts who worked on nuclear physics before and during World War II, since the war Motoharu Kimura has also worked to halt the nuclear arms race.

The temperature effect on the rate of spurious discharges in G. M. counters (hard glass sealed-off type with out-gassed cathode of 2 cm φ×5 cm) was observed when they were heated and cooled at constant rates. As shown in Fig. 2∼9, on the heating stage, the rate of natural counts increased in various manners which depended on the filling gases and on the cathode material, and decreased rapidly on the cooling stage without exception. It was verified that these discharges were due to the so-called. “Spontanentladung” of Trost and the occurrence of the double or triple discharges (Nachentladung) was very small. The plateau curves were taken with gamma ray source and also without any source before and after each experiment, and we could not find marked changes in them, though those. with natural counts became generally better after cooled. The plateau lengths were generally between 100 to 500v, with the, slopes of 0.6% to 10%/100v. The counts decreased exponentially with the square root of time when the counte... more...

The magnetic spectrometer to analyze the elastically and inelastically scattered electrons in combination with the Tohoku University 300-MeV electron linear accelerator is described with emphasis on its electron ladder and the data acquisition system. We employed Si(Li) semiconductor detectors combined with the conventional logic circuits for the coincidence counter telescopes and also for the other circuitry system. Three detector pieces were used per channel and a total of 33 such channels were employed. Data was collected during the beam pulse intervals of about 3.3 msec, after each pulse. The stability of the counting efficiency of the detector channel and the angular constancy of the effective solid angle of the spectrometer were examined. more...

Differential cross sections for scattering of He 4 by He 3 have been measured at E α =27.7, 28.5, 29.4, 30.0, 32.0, 33.4, 34.7, 36.5, 38.4, 41.0 MeV using a scintillation counter spectrometer, at the center of mass angles from ∼30° to ∼150°. Three distinct minima were found at about 45°, 100°, and 140°. The absolute cross-section and the pattern of the angular distribution showed no appreciable change in the energy range investigated: thus, there was found no sharp resonance in the He 3 +He 4 system corresponding to an excited state of Be 7 between 13.4 and 19.2 MeV. Differential cross-sections of the protons from He 3 (α, p )Li 6 Li 6* were observed. Differential cross-sections of alpha-alpha scattering were also measured at E α =33.5 and 35.5 MeV. more...

Photoproton cross sections for Mg, Al 27 , Si 28 and S 32 were measured using a betatron. A vacuum chamber with six detectors, each of which consists of a ZnS(Ag) scintillator and a photomultiplier, was used for the detection of photoprotons. The protons having larger energies than about 1.5 Mev were measured. The obtained yield curves were converted into the cross sections by Penfold-Leiss' method. The results are as follows: the giant resonance energies are 20, 20, 19.7 and 19.3 Mev for Mg, Al 27 , Si 28 and S 32 respectively: the widths at half maximum are 6, 7, 4 and 6 Mev; the integrated cross sections up to 23 Mev are 0.070, 0.11, 0.14 and 0.26 Mev-barns. more...

Diffusivity of Ag 110 in AgZn and AgCd alloys containing about 30% Zn or Cd was measured by means of surface counting. The results show that the silver atoms diffuse most rapidly in the lattice of AgZn and that the diffusivity of silver in AgCd is still higher than that in silver itself. These facts are interpreted by considering that the cohesive energy of the metallic lattice is affected by the addition of the impurity atoms not only due to the screening effect of the valence electrons but also, due to the change of the repulsive interaction of closed shells. more...

The diffractive scattering by crystals of thermal neutrons, which have the de Broglie wave-length of about 1.6 A, had been investigated by several authors. It gives many intersting facts, which may offer some means of supplementing the X-ray study of the solid state. In the present experiments the total cross section of thermal neutrons have been measured for Fe, Cu and Al as a function of the degree of cold-working. The thermal neutrons from a paraffin “howitzer” with 200_??_300 mC Rn-Be source are detected by a BCl3 ionization chamber and a linear amplifier as shown in Fig. 1. About 2000 counts per minute are obtained without a scatterer, and the residual counts due to higher energy neutrons above Cd cut-off are 5% or less. Completely annealed plates of electrolytic iron, Armco iron, pure Cu and pure Al are subjected to various degrees of cold-working (rolling). The final thickness of the scatterers is so regulated as to give about 50% transmission in each case. The experimental results are illustrated in Fig. 5, which shows the relative variation in the total cross. section as a function of the degree of working. It can be seen that the annealed samples of Fe and Cu show small cross sections which quickly increase to the saturation values by, a cold-working of an order of only a few per cent reduction of thickness. On the other hand, Al shows no marked change beyond the limit of experimental errors. After analysing the experimental results of Beyer and Whitaker on Fe, Halpern, Hamermesh and Johnson suggested, the existence of secondary extinction in the scattering of thermal neutrons by a single crystal. They also reaches the conclusions that the primary extinction must be negligible on account of the small interaction of neutron and nucleus, provided that the size of the mosaic block of Fe be of the order of 10-5cm. It would, however, be premature to conclude that Fe had such a small mosaic block, though-Miller and DuMond had determined the size of a block of Al to be of that order of magnitude from X-ray investigations; because, in general, the lower limit of the size of a mosaic block in metals-is considered to be in the order of 10-4cm after Bragg. The present results seem to point out the existence of the effect of primary extinction in annealed polycrystalline Fe and Cu. If we neglect the incoherent part of elastic scattering, the size of the mosaic block can be calculated by the same method as described in a previous paper by one of us (M. K.). According to Darwin, a measure of the degree of extinction is given by tanh mq/mq, where q is the, amplitude of the wave reflected by a certain net plane, and m is the number of net planes forming a mosaic block. By assuming that the primary extinction is completely removed by sufficient working, the size of a mosaic block is determined to be in the order of 5×10-4cm for annealed Armco iron, 3.6×10-4cm for annealed electrolytic iron and 5.8×10-4cm for annealed Cu. The reason why Al shows no marked decrease of cross section by annealing can be accounted for by the smallness of q and of the size of a mosaic block. Rasetti has found that in the case of Pb or Bi the cross sections are almost the same for the single and polycrystalline states and tried to attribute this fact to the isotope or spin disorder in crystal lattices. It is difficult, however, to explain our results on Al along these lines, because Al has only one isotope. more...

A preliminary study of applying the time-of-flight neutron diffraction method for the determination of the structure factor of liquid metals has been examined. The diffraction pattern of liquid Sn at 260°C has been measured using a time-of-flight neutron diffractometer incorporated with a pulsed neutron source from an electron linear accelerator, and a fairly good agreement between the present results and those of North et al.1) has been obtained. It is concluded that the T-O-F method incorporated with a pulsed neutron source can yield reliable data for the liquid metal structure analysis which are as accurate as those obtained from a steady reactor. more...

The photoneutron cross section of S/sup 32/ was observed up to 22 Mev with good energy resolution, together with the photoneutron spectrum using a stilbene scintillation spectrometer. Fine structures were observed in either of the two measurements. Taking into account the threshold energy and the excitation energies of the residual nucleus, these structures were shown to be consistently related with each other. Experimental results were discussed using the statistical model calculation, assuming that the emitted particles were only p-wave and f-wave particles. The integrated cross section ratio for S/sup 32/ ( gamma ,n) to P/sup 31/ ( gamma ,n) reaction and the same ratio for S/sup 32/ ( gamma ,p) to S/sup 32/ ( gamma ,n) reaction were well explained by the calculations. The difference between the energy spectrum of the photoprotons from P/sup 31/ and that from Si/sup 28/ also seemed to be well explained qualitatively. In the appendix, the contributions of the f-wave protons for the energy spectrum of photoprotons were shown. The photodisintegration of nuclei in these mass number region was concluded to occur mainly through the compound process in the giant resonance energy region. (auth) more...

Photoneutron cross sections and the yield curves were taken by the residual activity method for Ag 107 , Mo 92 and Zr 90 . Threshold energy were obtained as 9.35±0.1 MeV, 9.15±0.1 MeV, 12.38±0.1 MeV and 12.3±0.1 Mev for Ag 107,109 , Mo 92 and Zr 90 respectively. The energy for the maximum cross section was obtained as 14.5 MeV for Ag 107 , 16.5 MeV for Mo 92 and 17 MeV for Zr 90 . The giant resonance widths were measured about 5.3 MeV, 2.7 MeV and 2.9 MeV respectively. Intrinsic quadrupole moment determined from above data was (1.9±0.7)×10 -24 cm 2 for Ag 107 . more...

The elastic scattering of photons near the particle threshold energy was studied for Al, Si, S, K, Ca, Ni, Cu, Cd, Sn, Pb and Bi. The bremsstrahlung x-rays from a 25 Mev betatron were used. The pulse of the primary x-rays was expanded up to about 30 µ sec to decrease the pile-up effect. The scattered photons were detected at the scattering angle of 120 degrees with the scintillation spectrometer using an 8''φ×8''NaI(T1) crystal and a 30 channel pulse height analyser gated the expansion signal of the betatron orbit. The energy at which the cross section has a peak was compared with the particle threshold energy and the value of cross section was compared with that of particle emission. more...

The variation of the cross section for P 31 ( p , γ 0 ), ( p , γ 1 ) S 32 reactions with proton energy from 7.8 to 14.2 Mev, were measured using 4''φ×4'' Nal (T1) crystal spectrometers. The gamma rays corresponding to the transitions to the ground and first excited state of S 32 showed giant resonance with complicated structures. ( p , γ 0 ) falls off at about 13 Mev with full width of about 7 Mev if Harwell's result is combined. ( p , γ 1 ) does not show indications of fall-off at least up to about 14 Mev. Some results on Cu 65 ( p , γ) are also mentioned. more...

The energies and spins of lower excited levels in Nd 144 have been established by studies of the beta decay of Ce 144 –Pr 144 and the electron capture decay of Pm 144 . The experiments include the energy and relative intensity measurements, and directional correlation measurements of gamma rays by several NaI (T1) scintillation counters. The level of Nd 144 is populated at the 695 keV and 2190 keV from decay of Pr 144 , and the 695 keV, 1310 keV, and 1780 keV from the decay of Pm 144 . The levels at the 1220 keV and the 1560 keV which have been found by the neutron capture gamma ray measurements could not be found in both decay in the limit of about one percent. more...

The variation of the cross section for Al27(p, γ0 + γ1)Si28 with proton energy from 7.5 to 14.7 MeV, reveals the full structure of the giant resonance. Gamma ray yields for transitions to the ground and first excited states of the product nucleus were measured using a large NaI(Tl) crystal spectrometer. The width of the giant resonance is of the order of 4 MeV, with many resonance peaks and possibly with a splitting due to deformation. more...

Photoprotons from Si and P produced a 24-MeV betatron have been observed in nuclear emulsions. Fine structures are observed in the energy spectrum of Si, showing a fairly similar shape to the excitation curve of Al ( p , γ) reaction. The appearance of these structures is expected resonating group model and probably the channel coupling theory as well. The distances of the proton peaks in the spectrum are nearly equal to those expected these theories. The type of spectrum of Si is different from that of P, and such difference seems to appear between even and odd Z neighbouring nuclei. The angular distributions for P have large maxima around 90°, but those for Si have not so large maxima and minima. This suggests that the shell structure may have some effects on the photonuclear reactions. more...

The bremsstrahlung spretra of the 8.5-Mev electrons for the forward direction were measured with a scintillation spectrometer with a sodium iodide crystal 4 in. in diameter and 4 in. in length. Be, Ni, and Pt of several thickness were used as the targets. The measured spectra were compared with our semiempirical calculation. The calculation was based upon the response function for NaI crystal which was constructed referring to the method developed by NBS group and also to the actual response curve for the monochromatic gammas of 1.12 and 6.14 Mev, instead of using Monte Carlo method which had generally been used in the former researches. The agreement is rather good if Schiff's formula for the intrinsic bremsstrahlung spectra is assumed. (auth) more...

The Al/sup 27/( gamma ,n) cross section was measured up to 24 Mev with good energy resolution. Using a 25 Mev betatron, the yield of photoneutrons from Al/sup 27/ was determined for bremsstrahlung with peak energies ranging from 12.5 to 24 Mev in steps of 0.25 and 0.1 Mev. Neutrons were detected with eight B/sup 10/ enriched BF/sub 4/ counters in parrafin. (W.D.M.) more...

The 90 deg yields of gamma radiation produced from proton capture by Al/ sup 27/ were measured at proton energies of 7.5 to 14.5 Mev. The relative cross section data combined with these of Canberra revealed a giant resonance of width on the order of 4 Mev and with many peaks. Three resonances at 7.61, 8.75, and 10.13 Mev can be attributed to the excited state of Si/sup 28/. The giant resonance is interpreted from the standpoint of spheroidal deformation of a compound nucleus. (D. L.C.) more...

The energy spectrum of photoprotons from silicon-28 is investigated using 24 Mev bremsstrahlung. The energy loss is about 30% for 3 Mev and about 10% for 6 Mev protons. The number of detected tracks is 4366 for a scanned area of 1.6 cm². The energy spectrum is deduced by the statistical model with the level density omega given by omega = Cexp (E/2.8)Mev⁻¹. The many fine structures may be explained by a resonating group model. The cross section of Si²⁸( gamma ,p)Al²⁷ is compared with that for Al²⁷(p, gamma )Si²⁸ and the shapes coincide fairly well. (N.W.R.) more...

Photoneutron cross sections of P³¹ and S³² were measured up to 24 Mev by using bremsstrahlung from a 25 Mev betatron. Each neutron yield point was the result of four or five measurements involving a count of about 10⁴ for each point. Cross section curves and characteristic constants are shown. (W.D.M.) more...

The energy spectrum of 24-Mev bremsstrahlung photoprotons from S32 was studied using nuclear emulsions. The target thickness was 11.1 mg/cm2, which determined mainly the resolution of the result (about 2.5% for proton energy of 9 Mev). The cross section of S32( gamma ,p)P31 was estimated from experiments on P/sup 31/(p, gamma )S32. Such comparisons were possible for C12, O16, Ne20, Mg24, Si28, and Ca40 for which (p, gamma ) were previously studied. more...

A number of breaks are reported for the N/sup 14/( gamma ,n)N/sup 13/ activation curve in the energy region of 10 to approximately 17 Mev. The breaks are found to correspond to energy levels of N/sup 14/. It is concluded that the resonance of a single particle may not exist. (C.J. G.) more...

Photoproton spectra from P31 and Ca40 irradiated by 19 and 20.5-Mev bremsstrahlung, respectively, were observed using nuclear emulsions and previous methods (K. Shoda, et al., J. Phys. Soc. Japan, 16: 1807(1961)). Results were compared with the statistical model using the Weisskopf level density (V. F. Wofeisskopf and J. M. Blatt, Theoretical Nuclear Physics (John Wiley and Sons), 311(1954)). Data are presented in graphical form. more...

G. P. THOMSON1 has investigated the peculiar form of asymmetry in the scattering of electrons reported by Rupp2. According to Rupp, fast electrons when scattered first by gold through 90° and then passed through a gold foil show asymmetrical diffraction rings, while Thomson could not find any asymmetry up to the voltage of 160 k.v. more...