33 research outputs found

    Effects of Tillage and Residue Management on Soil Organic Carbon and Total Nitrogen in the North China Plain

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    Chinese Academy of Sciences XDA050500001 KSCX1-YW-09-06;Ministry of Science and Technology of China 2004CB720501A suitable tillage-residue management system is needed in the North China Plain (NCP) that sustains soil fertility and agronomic productivity. The objectives of this study were to determine the effects of different tillage-residue managements for a winter wheat (Triticum aestivum L.) and summer maize (Zea mays L.) double-crop system on soil organic carbon (SOC) and total N pools. No-tillage with residue cover (NTR), no-tillage with residue removed and manure applied (NTRRM), and conventional tillage with residue removed (CTRR) were investigated for 6 yr, based on a uniform N application among treatments. Soil samples were collected at six depths and changes in SOC and total N pools were analyzed. Treatments of NTRRM and NTR sequestered more SOC and total N in the 0- to 5-cm depth than CTRR. In the subsoil (5-60 cm), annual SOC sequestration was 0.01 and -0.40 Mg ha(-1) yr(-1) for NTRRM and NTR, respectively, while CTRR exhibited a significantly positive SOC pool trend. In the whole soil profile (0-60 cm), NTRRM, NTR, and CTRR sequestered SOC at the rates of 0.66, 0.27 and 2.24 Mg ha(-1) yr(-1). When manure was applied to substitute for the N lost from residue removal, the NTRRM tended to accumulate more SOC than NTR, and had similar accumulation as NTR in total N pools, grain yield, and aboveground biomass. Crop residue could be substituted by manure in this double-crop, irrigated system. Conventional tillage, with residue removed, was suitable in soil fertility and agronomic productivity relative to NTRRM and NTR in the NCP

    Microbially mediated mechanisms underlie soil carbon accrual by conservation agriculture under decade-long warming

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    Increasing soil organic carbon (SOC) in croplands by switching from conventional to conservation management may be hampered by stimulated microbial decomposition under warming. Here, we test the interactive effects of agricultural management and warming on SOC persistence and underlying microbial mechanisms in a decade-long controlled experiment on a wheat-maize cropping system. Warming increased SOC content and accelerated fungal community temporal turnover under conservation agriculture (no tillage, chopped crop residue), but not under conventional agriculture (annual tillage, crop residue removed). Microbial carbon use efficiency (CUE) and growth increased linearly over time, with stronger positive warming effects after 5 years under conservation agriculture. According to structural equation models, these increases arose from greater carbon inputs from the crops, which indirectly controlled microbial CUE via changes in fungal communities. As a result, fungal necromass increased from 28 to 53%, emerging as the strongest predictor of SOC content. Collectively, our results demonstrate how management and climatic factors can interact to alter microbial community composition, physiology and functions and, in turn, SOC formation and accrual in croplands.</p

    Microsurgery in 46 cases with total hand degloving injury

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    To summarize the characteristics of total hand degloving injury and investigate the curative effect of microsurgery. A total of 46 patients with total hand degloving injury were enrolled in this study. The injury classification and treatment methods were as follows: Type I (11 cases), treated by replantation of the gloved skin, Type II (6 cases), treated by reconstruction using thumb wrap-around flap and second toe, Type III (4 cases), treated by reconstruction using bilateral second toe with dorsal foot flap, Type IV (9 cases), treated by replantation in situ or reconstruction, Type V (16 cases), treated by replantation or abdominal flap reconstruction. Of the patients who received Type I treatment, five completely survived, whereas eight had finger necrosis. In Type II, both the reconstructed fingers and hand flaps survived. For four patients who received Type III treatment, eight reconstructed fingers survived. In Type IV, two patients with reconstructed fingers survived, whereas the six with replantation in situ had necrosis of the partial palmar or hand dorsum skin. In Type V, nine patients with reconstructed fingers survived, and five cases with abdominal skin flap reconstruction and one case with anterolateral femoral flap survived. The restoration of hand appearance and function was the best in patients who received replantation. For reconstruction cases, however, the hand function was recovered to the basic self-care level. In cases with abdominal flap reconstruction, the hand function showed poor recovery. Total hand degloving injury can be classified into different types according to the injury degree. The appropriate microsurgical treatment based on these types can produce better curative effect

    Microsurgery in 46 cases with total hand degloving injury

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    Objective: To summarize the characteristics of total hand degloving injury and investigate the curative effect of microsurgery. Methods: A total of 46 patients with total hand degloving injury were enrolled in this study. The injury classification and treatment methods were as follows: Type I (11 cases), treated by replantation of the gloved skin; Type II (6 cases), treated by reconstruction using thumb wrap-around flap and second toe; Type III (4 cases), treated by reconstruction using bilateral second toe with dorsal foot flap; Type IV (9 cases), treated by replantation in situ or reconstruction; Type V (16 cases), treated by replantation or abdominal flap reconstruction. Results: Of the patients who received Type I treatment, five completely survived, whereas eight had finger necrosis. In Type II, both the reconstructed fingers and hand flaps survived. For four patients who received Type III treatment, eight reconstructed fingers survived. In Type IV, two patients with reconstructed fingers survived, whereas the six with replantation in situ had necrosis of the partial palmar or hand dorsum skin. In Type V, nine patients with reconstructed fingers survived, and five cases with abdominal skin flap reconstruction and one case with anterolateral femoral flap survived. The restoration of hand appearance and function was the best in patients who received replantation. For reconstruction cases, however, the hand function was recovered to the basic self-care level. In cases with abdominal flap reconstruction, the hand function showed poor recovery. Conclusion: Total hand degloving injury can be classified into different types according to the injury degree. The appropriate microsurgical treatment based on these types can produce better curative effect

    Methods of Immobilization after Achilles Tendon Rupture Repair: A Comparative Study in Rat Model

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    Objective The Achilles tendon (AT) is the most frequently ruptured in the human body. Literature describing different immobilization methods' impact on tendon healing after AT repair is lacking. We compare plaster cast, splint, and K‐wire to determine which is the most stable and has the fewest complications. Methods Sixty rats aged 5–6 months were selected to establish Achilles tendon injury in two hind legs model. After suturing the ends of the AT together with a modified “Kessler” method (Prolene 5–0). The skin incision was interrupted and sutured with 1–0 thread. Rats were divided into three immobilization methods (plaster cast group, splint group, and K‐wire group). In plaster cast group, the hind leg was cast with plaster in the extended position of the hip and knee joints, and the ankle joint was at 150°. Splint and K‐wire group used splints and 0.8‐mm K‐wires, separately. The fixed period was 4 weeks. The incidence of stability and complications (death, necrosis of the legs, necrosis of the skin, and incisional infection) were recorded. Differences were detected using the chi‐square test. Results Within 4 weeks observation, K‐wires showed better stability (90%) compared with the other two ways (40% in plaster cast group, 65% in splint group; p < 0.05). Rats immobilized with K‐wires (10%) suffered significantly lower complications compared with plaster cast and splint group (15%; p < 0.05). Conclusion K‐wire has better stability, lower complication rate than other methods. Immobilization with K‐wire may be a promising tool in future clinical Achilles tendon rupture applications

    Method for reconstructing femoral head blood supply by anastomosing the intraosseous artery

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    Background: The reconstruction of femoral head blood supply is crucial in the management of avascular necrosis and related conditions. This study presents a method for reconstructing the femoral head blood supply by anastomosing the intraosseous artery. Methods: The femoral heads of six male Landrace swine were surgically exposed, and subcranial fractures of the femoral neck were intentionally created. Under microscopic guidance, the trophoblastic foramen of the posterior supporting artery was identified. Subsequently, a triangular bone window was carefully crafted to expose the intraosseous artery. Following the fixation of the femoral head, an anastomosis was performed between the intraosseous artery and the posterior inferior supporting artery located at the distal end of the fracture. The assessment of femoral head blood supply was conducted using Kirschner's pinhole and angiography techniques. Results: The anastomotic intraosseous artery exhibited a vibrant red color, indicating adequate blood perfusion, and demonstrated pulsatile flow. Observation through pinholes in the surface of the femoral head revealed continuous blood flow. Angiography further confirmed the successful circulation, as the contrast agent entered the inferior retinacular artery branch originating from the deep femoral artery. The contrast agent then proceeded to enter the femoral head through the retinacular artery, reaching the anastomosis site of the intraosseous artery. Notably, the angiography also revealed the presence of visible internal branches, highlighting the establishment of a functional vascular network. Discussion: The method of reconstructing the blood supply to the femoral head through anastomosis of the intraosseous artery enables utilization of the existing blood supply system within the femoral head. This study is just a preliminary study of this innovative technique that has the potential to prevent and/or treat femoral head necrosis following a femoral neck fracture. By restoring adequate blood flow to the affected area, this approach holds promise in preserving the viability and functionality of the femoral head, ultimately improving patient outcomes

    Anatomical characterization of the intraosseous arteries of the porcine tibia

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    Introduction: Tibial fractures have a high rate of post-fracture complications. Blood supply is recognized as a positive factor in tibial fracture healing. However, it’s difficult to assess blood supply damage after tibial fracture because of the lack of understanding of the tibial intraosseous arteries. This study aimed to delineate and anatomically characterize porcine tibial intraosseous arteries, as a model for the human system. Methods: Twenty right calf specimens with popliteal vessels were prepared from ordinary Landrace pigs. Epoxy resin was perfused into the vasculature from the popliteal artery. After 24 h, casts of the intraosseous arteries of the tibia were exposed through acid and alkali corrosion. The distribution and anatomy of the exposed intraosseous arteries were observed and measured under a microscope, and the data were statistically analyzed. Results: Sixteen complete specimens were obtained. The medullary artery bifurcated into the main ascending and descending branches, which each split into two upward primary branches that further divided into 1–3 secondary branches. Among all specimens, 56 ascending and 42 descending secondary branches, which were all ≥0.3 mm in diameter. Furthermore, the horizontal plane was divided into three zones—safety, buffer, and danger zones—according to the probability of the presence of intraosseous artery. Discussion: The cast perfusion and corrosion approach was successfully applied for anatomical characterization of the intraosseous arteries of the porcine tibia. These observations provide a theoretical basis for understanding the tibial vasculature in humans and will facilitate the establishment of novel “safe corridor” in the tibia for the protection of the blood supply during surgery

    Experimental analysis of femoral head intraosseous vascular anastomosis in the treatment of porcine subcapital femoral neck fractures

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    Introduction: Femoral neck fractures are challenging injuries associated with a compromised blood supply to the femoral head, leading to a high risk of avascular necrosis and poor clinical outcomes. This study aimed to investigate the efficacy of femoral head intraosseous vascular anastomosis in the treatment of porcine sub-capital femoral neck fractures. Methods: Ten Landrace pigs were used as experimental animal models. The femoral head was completely removed after femoral neck sub-cephalic fracture. It was fixed on the medial side of the knee joint, and the blood supply to the femoral head was reconstructed by anastomosing the femoral head vessels. One week later, blood flow in the femoral head was observed by borehole, digital subtraction angiography examination, and hematoxylin and eosin staining. Further, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling tests were performed to detect pathological changes in the femoral head. Results: After one-week, digital subtraction angiography of the femoral head revealed a blood circulation rate of 70 %, and the blood seepage rate of the borehole was 80 %. Hematoxylin and eosin staining and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling test results showed that necrosis of bone marrow cells in the experimental group was significantly improved compared to that in the control group. Discussion: This study highlights the potential benefits of femoral head intraosseous vascular anastomosis in the treatment of porcine sub-capital femoral neck fractures. Further research and clinical trials are warranted to validate these findings and to explore the translational potential of this technique in human patients
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