SNR-enhanced signal delivery scheme with delta-sigma modulation in a four-mode fiber system.

This Letter proposes a scheme for optimizing the signal-to-noise ratio (SNR) of signal to improve the system performance by a 1 bit delta-sigma modulation (DSM) in a four-mode MDM system for mobile fronthaul. A 1 bit digitalized signal with an SNR of 60 dB from transmitter digital signal processing (Tx DSP) can be achieved. Based on this system, an experimental demonstration of the ultrahigh-order 1048576-QAM signal transmission over a 50 km strong-coupling few-mode fiber (FMF) is successfully realized. With DSP, the bit error rate (BER) of the received 1048576-QAM signals over four modes transmission is below the 20% soft-decision forward error correction (20% SD-FEC) threshold of 2.4 × 10-2. To the best of our knowledge, this is the first time that the combination of DSM technology and strong-coupling MDM system is achieved and that the highest-modulation order with DSM reported in MDM system is reached. This experimental demonstration of the proposed novel scheme in MDM system can provide an effective solution for ultra-large-capacity mobile fronthaul in the future.

Reconstruction of complex chest wall defects: A case report.

BACKGROUND: Chronic radiative chest wall ulcers are common in patients undergoing radiation therapy. If not treated early, then symptoms such as erosion, bleeding and infection will appear on the skin. In severe cases, ulcers invade the ribs and pleura, presenting a mortality risk. Small ulcers can be repaired with pedicle flaps. Because radioactive ulcers often invade the thorax, surgeons need to remove large areas of skin and muscle, and sometimes ribs. Repairing large chest wall defects are a challenge for surgeons. CASE SUMMARY: A 74-year-old female patient was admitted to our department with chest wall skin ulceration after radiation therapy for left breast cancer. The patient was diagnosed with chronic radioactive ulceration. After multidisciplinary discussion, the authors performed expansive resection of the chest wall ulcers and repaired large chest wall defects using a deep inferior epigastric perforator (DIEP) flap combined with a high-density polyethylene (HDPE) patch. The patient was followed-up 6 mo after the operation. No pigmentation or edema was found in the flap. CONCLUSION: DIEP flap plus HDPE patch is one of the better treatments for radiation-induced chest wall ulcers.

Strategies for the selection of oncoplastic techniques in the treatment of early-stage breast cancer patients.

BACKGROUND: In recent years, breast cancer is the most common malignancy in women. The traditional method of surgery is to remove a woman's breast completely, which has a negative impact on her work and life. Today, women have a fiery pursuit to maintain their perfect figure, which has forced breast surgeon to find a new surgical approach to maintain the shape of the breast after surgery. METHODS: This study systematically analyzed and summarized the incision design and repair of glandular defects in early-stage breast cancer patients by oncoplastic breast techniques. By summarizing the methods of oncoplastic breast surgery (OBS) in different quadrants, it could help beginners to master this technology more quickly, so as to provide better help for breast cancer patients. RESULTS: A total of 216 breast cancer patients who underwent OBS from January 2016 to June 2020 at the Affiliated Hospital of Guangdong Medical University were included in this study. In patients treated with the volume-displacement method and the volume-replacement method, 92.6% and 86.2% of patients achieved excellent breast shape, respectively. CONCLUSIONS: OBS is a safe and effective way to treat early-stage breast cancer while obtaining better breast shape, reducing postoperative psychological trauma, and improving quality of life.

Modified radical mastectomy for anterior thoracic nerve and intercostobrachial nerve protection (case report).

Modified breast cancer radical mastectomy is a more common operating method in breast surgery. Traditional modified radical mastectomy focuses on protecting the long thoracic nerve and thoracodorsal nerve while ignoring the protection of the anterior thoracic nerve and intercostobrachial nerve protection, which leads often to patients with upper medial arm numbness, acid swelling, pain, chest atrophy, and other problems. In the modified radical mastectomy of breast cancer, in this case, the author used an elaborative operation to protect the anterior thoracic nerve and intercostobrachial nerve and thoroughly dissected the third-level lymph nodes through the axillary approach.

Reconstruction of the chest wall in locally advanced breast cancer with multi-disciplinary cooperation: a case report of mesh repair plus TRAM combined with DIEP chest wall reconstruction.

Locally advanced breast cancer, which is defined as a malignant breast tumor that invades or adheres to the surrounding tissue, is characterized by the invasion of the chest wall and the skin surface by the tumor. Multiple lymph nodes are invaded and fuse into a mass, causing extensive axillary lymph node metastasis. However, locally advanced breast cancer does not exhibit distant metastasis. At present, in most hospitals in China and the rest of the world, this type of breast cancer is primarily managed through systematic and local treatments. However, a consensus concerning the optimal surgical method for chest wall reconstruction, which for many surgeons is a difficult and confusing procedure, has not been reached. In the past, many breast centers had used skin flap combined with hard mesh titanium alloy plate to repair the large chest wall defects. Although titanium alloy plate can maintain the stability of the chest wall, it may have a negative effect on the follow-up radiotherapy of breast cancer patients, which is a controversial method. In addition, titanium alloy mesh also has the risk of deformation and fracture. These factors will cause some hidden dangers to patient safety. According to the research, the soft mesh not only has the characteristics of satisfactory compatibility and robustness for maintaining the stability of chest wall, but also does not affect the postoperative radiotherapy of patients. Combined with the advantages of soft mesh, Our department treated a case of locally advanced breast cancer with chest wall invasion. Through cooperation between the breast surgery and thoracic surgery departments, a mesh repair plus transverse rectus abdominis myocutaneous (TRAM) combined with deep inferior epigastric perforator (DIEP) procedure was performed to remove the breast tumor and repair the large area of skin defect after surgery, and a relatively satisfactory therapeutic effect was achieved. In this case, we took two novel approaches: first, a 4-layer high-density polyethylene mesh was used to repair the defect; secondly, the inferior epigastric artery perforation was anastomosed with the thoracoacromial artery (end-to-end anastomosis) and the inferior epigastric vein perforation was anastomosed with the axillary vein (end-to-side anastomosis).