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Background The Quaternary had worldwide consequences in forming the contemporary diversity of many populations, species and communities, which is characterized by marked climatic oscillations between glacial and interglacial periods. The origin and evolution of biodiversity in mountainous areas are highly dependent on historical orogenesis and associated climatic changes. The Chinese grouse Tetrastes sewerzowi is a forest-dwelling species endemic to the mountains to the east of the Qinghai–Tibet Plateau, which has been listed as Near Threatened with a decreasing trend by the IUCN because of ongoing deforestation and fragmentation of coniferous forests. It is important to place current population status into a broader ecological and evolutionary context to understand their demographic history. Results Analyses of the Chinese Grouse genome revealed fluctuations throughout the Pleistocene in effective population size. Populations decreased during early to middle Pleistocene but showed an expansion during late Pleistocene which was then followed by a sharp decline during the last glacial maximum (LGM). Ecological niche modeling indicated that a suitable habitat shift between high altitude regions to low altitude regions was due to a changing climate. This result parallels patterns of population size change in Chinese Grouse estimated from PSMC modelling, which suggested an expansion in population size from the last interglacial period (LIG) and then a peak and a bottleneck occurring at the last glacial maximum (LGM). Furthermore, the present-day distribution of Chinese Grouse is greatly reduced and fragmented. It will likely become even more fragmented in the future since coniferous forest cover is threatened in the region of their distribution and the availability of such habitat restricts their ecological niche. Conclusions The Chinese Grouse have experienced substantial population size changes from the beginning to the LIG and reached a peak before the LGM. A sharp decrease and bottleneck occurred during the LGM, when the coniferous forests were subjected to extensive loss. The results inferred from the whole genome sequencing and species distribution models both support historical population fluctuations. The distribution of the Chinese Grouse is strongly dependent on the coniferous forest cover. To protect the fragmented coniferous forests is an essential action to protect the Chinese Grouse.

Background Incubating birds must balance the conflict between thermal needs of the developing embryos and their self-maintenance needs for energy. The Chinese Grouse (Tetrastes sewerzowi) lives in high mountain conifer forests and faces energy stress, cold environment, and predation pressure. Females might adjust incubation rhythm to adapt to these constraints. Methods Two methods were used to investigate egg laying and incubation pattern of the Chinese Grouse; 25 nests were monitored by data loggers and 12 nests by infrared video cameras. Results Female Chinese Grouses usually laid an egg every 2 days. The incubation period was 28–31 days. Overall incubation constancy for Chinese Grouse was 93%. The females took 5.0 recesses per day and 34% of all 1696 recesses were taken in the crepuscular period. The average recess duration was 20.3 min. Females took more and shorter recesses in the latter part of incubation. The females who allocated more time to foraging had a higher reproductive success. Conclusions Probably due to its high egg/body mass ratio, the Chinese Grouse has a long laying interval of 49 h. We suggest that, due to energy stress, females have relatively more recesses and they increase the number of recesses as incubation progresses. To compensate for the embryos’ thermal needs, they extend the incubation period and shorten the recess duration in this cold environment.

In order to obtain the transmission properties of one-dimensional phononic crystal under total evanescent waves, we design structure model. Basing on the basic acoustic wave equations and boundary condition as well as the Bloch theory, we study the band structure of one-dimensional phononic crystal. We summarize the properties of the mode based on the coupling of total evanescent waves and explain its physical mechanism. There are three transmission modes in phononic crystal. Based on the coupling of total evanescent waves, the number of perfect transmission peaks is just equal to the number of structure period, and the thickness of period can be much less than the wave length.

We studied the breeding ecology of the fulvous parrotbill (Paradoxornis fulvifrons) and provide the first description of nests, eggs, fledglings, nesting behaviour and nest sites from China. Nests were bowl-shaped built by both sexes mainly of bamboo leaves, fibrous roots and mosses. They were located within dense bamboo clusters, about 0.70–1.90 m above the ground. The clutch size averaged (mean ± SD) 3.38 ± 0.72 (n = 16) and eggs were oval, pale blue in colour, weighing 1.24 ± 0.10 g (n = 13). Both pair-bond members incubated eggs and shared nestling care. Compared with control sites, the nest sites (n = 33) had smaller canopy closure (73 ± 12% vs 84 ± 16%). Overall nesting success was 18.18% (6/33). We concluded that human disturbance (i.e. tourist hiking on paths close to nest sites) might prompt nest desertion causing the low reproductive success of fulvous parrotbill in the reserve.

This paper uses TMS320F28335 DSP and MAX3032S CPLD as the controller of the 6/4 pole switched reluctance motor (SRM), and controls the motor by the method of current chopping control (CCC) in low speed and the method of angle position control (APC) in high speed. About the optimization of turn-on angle and turn-off angle when SRM is controlled by the method of APC, this paper discusses the optimal design of the two parameters by ways of theory research, simulation and experimental testing. The results show optimal switching angle can make speeded-up of the motor better and improve the performance of SRM.

We employ the Bloch theorem of periodic structures and transfer matrix method to study the surface modes of a semi-infinite one-dimensional photonic crystal coated with a metal film. There are two mechanisms guiding the surface modes: the surface plasmon resonances and the surface modes of periodic structure. The surface modes can occur in all lower gaps and result from different mechanisms in different gaps. Extremely slow group velocities and even negative group velocities have been found to these surface modes.

We found nine nests of the Grey-hooded Parrotbill (Paradoxornis zappeyi) during April through July 2003 at Wawushan Natural Reserve, Sichuan, southwestern China. This report is the first description of the nest sites, nests, eggs, and breeding behavior of this parrotbill, and the first documentation of nestling growth from hatching until fledging. The nests were constructed mainly of bamboo (Bashania faberi) leaves, fibrous roots, and moss by both male and female. Nests were bowl shaped and in bamboo thickets 81–122 cm above ground, and 17–68 cm below the top of bamboo leaves. Clutch size was 3.1 eggs (n = 8 nests) and eggs were oval, pale blue in color with a mean mass of 1.3 g. Incubation and provisioning of nestlings were by both parents. The nestling period was 13–14 days with a hatching rate of 0.52 and mean reproductive success rate of 0.48 fledglings per nest.

The Sichuan Treecreeper, Certhia tianquanensis Li 1995, was recently recognized as an independent species. Apparently, it is an endemic relict occupying an extremely small range in western Sichuan and Shaanxi provinces, China. During April–July 2003, its breeding biology was studied using field observation and data logger records of five nests found on Wawu Shan in Sichuan province, southwest China. Nest materials were mainly mosses; eggs are white with dense red spots concentrated at the large pole. During the incubation period, the male fed the female outside the nest with 6–13 min intervals between the single feeding events; afterwards, the female regularly returned to the nest within 47.8 ± 25.2 s. The female took 22.14 ± 3.24 recesses per day, with the mean recess length of 8.18 min throughout the incubation period. After the nestlings hatched, the female went out more often than during the incubation period: 55 and 56 times during the first 2 days of nestling period (off-nest time of 6.55 ± 3.15 min). Both parents fed the nestlings.

We describe for the first time the characteristics of the nest sites, nests, eggs, and nestling behavior of the endemic Snowy-cheeked Laughingthrush (Garrulax sukatschewi). During May and June 2002, at the Lianhuashan Natural Reserve in central China, we found five nests in coniferous forest at an elevation of 2,850 m. All nests, built by both members of a pair, were cup shaped and built 1.2–2.8 m above the ground in the branches of spruce (Picea spp.) trees or willow (Salix spp.) shrubs. The eggs were unspotted and greenish blue. We observed one brood of three nestlings. The parents fed the nestlings at a frequency of about 7.9 times/h ± 2.8 SD, with the female performing 51.6% of the feedings. Both male and female adults removed the feces from the nest at a mean rate of 6.9 times/h.