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231.
Knowledge about historical photographic collections of Papua New Guinea (PNG) is limited both in source communities and amongst scholars. This article aims to shed light on significant collections of PNG photographs, describing some of the collections, and pointing to their importance at both ends of the ‘exchange’. I discuss some limitations in present uses of these visual records and point to the need for repatriation initiatives. The poor knowledge of extant photographic collections among today’s Papua New Guineans is described, and I raise some thoughts about what this signals to archives and researchers. As examples, special mention is given to the collections of photographers Albert English, William Saville, Rudolf Pöch and Captain F.R. Barton. Finally, I comment on current challenges and future opportunities for the keepers of these historical collections. A list of the collections mentioned in the article can be found at the end.  相似文献   
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Johann Jakob Wepfer (1620–1695), city physician in Schaffhausen, Switzerland, published two books on “apoplexy.” He proposed new ideas about the events in the brain during such attacks, based on Harvey’s theory of the circulation of the blood. Wepfer postulated extravasation of whole blood or serum in the brain, in opposition to the Galenic notion of blocked ventricles. His case histories are remarkably precise and untainted by interpretation. This allows the recognition of a patient with word blindness, who was also unable to read words written by himself. Unlike patients with pure “alexia without agraphia,” he could not write complete sentences because of additional language defects, especially speech comprehension. Jules Dejerine (1849–1917) would, in 1892, not only describe a patient with the pure form of this syndrome (cécité verbale avec intégrité de l’écriture spontanée et sous dictée) but also provide an explanation of its anatomical basis.  相似文献   
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Although the leadership of the Revisionist Union originated in a similar socio-economic milieu, it was far from being homogenous. Different perceptions of the relationship with the existing Zionist Organization became the most prominent ideological impetus to disintegration. The years 1931–33 were the final stage of this process, marked by constant disputes and ambiguous interpretations of the various compromise formulas that were drafted. The article seeks to demonstrate that Jabotinsky's alliance with the extremist trends of the Revisionist movement was a by-product of his inability to dominate the moderate party apparatus, rather than a result of ideological proximity with the extremists.  相似文献   
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The Seismic Hazard Assessment (SHA) based on probabilistic approach has been carried out for the entire seismically active NW Himalayan Fold and Thrust Belt in Pakistan. Additional information in the form of earthquake catalog, delineation of 41 active faults in a structural map, their relationship to the seismicity, and establishment of seismotectonic zones has also been undertaken.

From the distribution of the 813 events within the study area, it appears that seismicity (≥4.0 Mw) is associated with both surface and blind faults. The clustering of events in specific parts along the surface faults shows that some fault segments, especially in the hinterland zone, are more active. In parts of the active deformational front, like the Salt Range, southern Potwar and Bannu, lesser seismic activity (≥4.0 Mw) could be due to damping effect of the thick Precambrian salt.

A majority of the earthquakes (86%) range in magnitude from 4.0 to 4.9 Mw, followed by 107 events (13%) ranging from 5.0 to 5.9 Mw. The remaining 1% range from 6.0 to 6.7 Mw. There is a predominance of shallow seismicity (<50 km focal depth). Larger magnitudes events are more in the hinterland zone. In contrast, based on distribution of 683 (≥4.0 Mw) events, a deeper level of seismicity (50 to 200 km) prevails especially in the adjoining Hindukush Range of Afghanistan.

Four seismotectonic zones have been established in the area. The b value is highest for the Peshawar-Hazara Seismic Zone (PHSZ) at 1.27, followed by 1.12 for the Surghar-Kurram Seismic Zone (SKSZ). The Swat-Astor Seismic Zone (SASZ) and Kohat-Potwar-Salt Range Seismic Zone (KPSZ) have b values of 0.99 and 1.03, respectively, thereby indicating the occurrence of more events of relatively higher magnitude as compared to the other two zones. The mean activity rate of the earthquakes (λ) ranges from 4.26 to 1.73. In decreasing order, the values are 4.26, 2.62, 2.07, and 1.73 for PHSZ, SASZ, KPSZ, and SKSZ, respectively. Using four regression relationships, the maximum potential magnitude (m1) has been determined for the 4 Quaternary faults. The highest value within each seismic zone represents its m1. Our calculations show that m1 is 7.8 in the hinterland (SASZ and PHSZ) and 7.4 in the foreland part (KPSZ and SKSZ).

SHA, incorporating probabilistic approach, has been undertaken at 10 sites, along with disaggregation at the assigned amplitude of 0.2g. Pakistan does not have an attenuation equation of its own. The two equations of Ambraseys et al. (1996) Ambraseys, N. N., Simpson, K. A. and Bommer, J. J. 1996. Prediction of horizontal response spectra in Europe. Earthquake Engineering and Structural Dynamics, 25: 371400. [Crossref], [Web of Science ®] [Google Scholar] and Boore et al. (1997) Boore, D. M., Joyner, W. B. and Fumal, T. E. 1997. Equations from estimating horizontal response spectra and peak acceleration from western North American earthquakes: a summary of recent work. Seismological Research Letters, 68: 128153. [Crossref] [Google Scholar] have been used and the results obtained using the equation of Boore et al. (1997) Boore, D. M., Joyner, W. B. and Fumal, T. E. 1997. Equations from estimating horizontal response spectra and peak acceleration from western North American earthquakes: a summary of recent work. Seismological Research Letters, 68: 128153. [Crossref] [Google Scholar] have been preferred. In the Probabilistic seismic hazard assessment (PSHA), the PGA values with 10% probability of exceedance in the 50 years, i.e., the return period of 475, have been determined using the EZ-FRISK (6.2 beta version) software. Best-estimated seismic hazard parameters (λ, m1, m0, and the β value) of the four seismic zones were used as the input. Results were generated in the form of total hazard curves. Values obtained range from 0.08g (for Bannu) to 0.21g (for Malakand and Kohat). For the other seven sites they are: Astore (0.082g), Kaghan (0.12g), Muzaffarabad (0.13g), Islamabad and Peshawar (0.15g), Talagang (0.16g), and Mangla (0.18g). High population density and more poorly constructed structures in Rawalpindi (twin city of Islamabad) and Peshawar make them more hazardous.  相似文献   
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