First record of the bee genus Bathanthidium (Bathanthidium s. str.) Mavromoustakis (Hymenoptera: Megachilidae) from Vietnam: Description of a new species and a key to species

The little-known bee genus Bathanthidium Mavromoustakis, 1953 of the family Megachilidae is reported for the first time from Vietnam. A new species, Bathanthidium (Bathanthidium s. str.) paco Tran & Nguyen, sp. nov. from Hoa Binh province is described and illustrated. A nest of the new species is reported from a wooden house. An updated identification key to all known species of the subgenus Bathanthidium s. str. is also provided.

Validation of the Low-Frequency Procedure for Field Measurement of Façade Sound Insulation

In the ISO 16283 series for field measurement of sound insulation, a low-frequency procedure is specified for determining indoor average sound pressure level, which is the so-called corner method. In the procedure, additional measurements are required in the corners in addition to the default measurements in the central zone, and the indoor average level is corrected with the highest level in the corners. However, this procedure was empirically proposed, and its validity is not fully examined for façade sound insulation. In this paper, detailed experiments were performed in a mock lightweight wooden house for validating the low-frequency procedure for façade sound insulation measurement. The results suggest that a correction with energy-averaging level of all corners is more reliable than with the maximum level, and the uncertainty in the default procedure is sufficiently improved with additional measurements in four non-adjacent corners. Moreover, the effect of the detailed position of the microphone around the corner was clarified for a more specific instruction.

OVERVIEW OF MODERN WOODEN HOUSING CONSTRUCTION IN RUSSIA

Wooden house building has centuries-old traditions, to which Russia has made a significant contribution. Historically, our country is rich in forests, hence the quite natural choice of wood as the main material for housing construction. Everyone knows the methods of building wooden houses by Russian architects of the early Middle Ages “with one ax and without a single nail.” Well, of course, we must understand here that there was more than one ax, there were auxiliary manual wood-cutting tools. Well, without nails – it does not mean at all that the connecting elements were not used, they just were also wooden. Some of these monuments of wooden architecture have survived to this day and we can observe them, for example, in Kizhi, Vologda, Arkhangelsk and many other cities.

The urban wooden house and its fate

Wooden architecture is regarded as a basis for Russian cultural identity. A short journey into the history of its preservation is made. The design and practical experiences of Irkutsk, Tomsk, Nyandoma and Tallinn are viewed as contemporary examples of preservation of wooden urban houses. The author considers starting demolition of the unique workers’ settlement Chagoda built from wood in the constructivist style to be one of the recent losses. The article points out the necessity of cardinal public reevaluation of national values and a traditional Russian wooden house.

Distribution of Holocene Marine Mud and Its Relation to Damage from the 1923 Earthquake Disaster in the Tokyo Metropolitan Area, Japan

Tokyo, which is located near the boundary between the North American and Philippine Sea plates, has been frequently struck by large earthquakes throughout the Holocene. The 1923 Taisho Kanto Earthquake is a rare historical earthquake that can be reconstructed in detail because abundant datasets were collected by investigations performed just after the earthquake. We examined 13,000 borehole logs from the Tokyo and Nakagawa lowlands to clarify the distribution and thickness of incised-valley fills and soft marine mud that had accumulated since the Last Glacial Maximum (LGM) on a grid with a resolution of 150 m × 150 m. We compared these datasets with the distribution of wooden house damage ratios caused by the Taisho Kanto Earthquake. Our results showed that the thickness of the soft mud, but not that of the incised-valley fills, was strongly correlated with the wooden house damage ratio. The mud content was >60%, water content was >30%, and S-wave velocity was ca. 100 m/s in the soft Holocene marine mud. The wooden house damage ratio was highest where the soft mud thickness was 20 m, because in those areas, both the soft mud and the wooden houses resonated with a natural period of ca. 1 s.