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Dolomite exhibits a wide distribution in geological strata. The metabolic activities of microorganisms in marine sediments play a crucial role in the formation of dolomite. Semiconducting minerals, such as hematite, goethite, and rutile, generate photoelectrons when exposed to sunlight, which can impact the community structure and metabolic activities of microorganisms. In this study, a simulated photoelectron system was conducted to investigate the response of the microbial community, as well as the regulation of sulfate reduction, to photoelectrons using high-throughput sequencing of the 16S rRNA gene. The regulatory effect of semiconducting mineral photoelectrons on the induction of carbonate precipitation by sulfate-reducing bacteria was explored. X-ray diffraction and Raman spectroscopy were used to characterize carbonate precipitation. During cultivation, the pH values of the system increased from 8.0 to approximately 8.5 and the rate of sulfate reduction was significantly enhanced under the influence of simulated photoelectrons. The alpha diversity of the microbial community decreased, and the semiconducting mineral photoelectronic system had a promoting effect on the enrichment of sulfate-reducing bacteria, mainly Desulfovibrio. Under the regulation of photoelectrons, sulfate-reducing bacteria can effectively oxidize organic matter and reduce sulfate in the environment, and proto-dolomite can be formed at a low Mg/Ca ratio. This process has important implications for carbon and sulfur element cycling in estuarine and oceanic photic zones, and provides a new explanation for the formation of large amounts of dolomite in geological history.

Background The treatment of chronic calcaneal osteomyelitis remains a challenge for orthopedic and plastic surgeons. The basis of surgical therapy includes thorough debridement of infected tissue and reconstruction with well-vascularized flaps. Methods A “hybrid” sural flap composed of an adiponeurofascial flap proximally and a neurofasciocutaneous flap distally is described here. The adiponeurofascial flap was used to obliterate the bone cavity, and the distal part was used to resurface soft tissue defects. Five patients with chronic calcaneal osteomyelitis were treated with this modified sural flap. Results The size of the adiponeurofascial flap ranged from 5.0 × 4.0 cm to 13.0 × 5.0 cm, and that of the neurofasciocutaneous flap ranged from 6.5 × 3.0 cm to 6.0 × 8.0 cm. The donor defects were covered with skin grafts in three patients and closed primarily in two patients. All the flaps survived completely without any complications, the skin graft and the skin over the adiponeurofascial flap healed uneventfully. There was no evidence of recurrent infection during the follow-up period. Conclusion The modified “hybrid” sural flap is simple and reliable and is a good candidate for treatment of chronic calcaneal osteomyelitis.

With the Drucker-Prager yield criterion, the ANSYS software is used to analyze the long-short-pile composite foundation by using three-dimensional nonlinear finite element method. The influences of load on axial stress and maximal axial stress of head of pile with cushion or not have been investigated by simulating composite foundation through nine long piles and sixteen short piles. The result indicates the cushion can reduce the stress concentration in head of pile effectively with increase of load. This conclusion has a certain value for engineering.

Reconstruction of flexor function of forearm remains a challenge in the reconstructive surgery. With development of microsurgical techniques, reconstructive surgeons have been able to envision muscle transplantation for restoration of function and not simply for provision of soft tissue coverage. In this report, we present our experience in three patients of successful treatment of traumatic flexor loss in the forearm with the microsurgical medial gastrocnemius myocutaneous flap. At 18- to 24-months follow-up, the detected action potential (Latency and Amplity) in the transferred muscle was significantly improved in the EMG examination. The strength of the digital flexion reached to III degree in one case, IV degree in two cases. No complications were noted in the donor legs. We conclude that the microsurgical medial gastrocnemius myocutaneous flap transfer can be an ideal alternative for functional reconstruction of the forearm flexor muscle in three posttrauma patients.