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BACKGROUND: Isolated gastrointestinal venous malformations (GIVMs) are extremely rare congenital developmental abnormalities of the venous vasculature. Because of their asymptomatic nature, the diagnosis is often quite challenging. However, as symptomatic GIVMs have nonspecific clinical manifestations, misdiagnosis is very common. Here, we report a case of isolated diffuse GIVMs inducing mechanical intestinal obstruction. A literature review was also conducted to summarize clinical features, diagnostic points, treatment selections and differential diagnosis in order that doctors may have a comprehensive understanding of this disease. CASE SUMMARY: A 50-year-old man presented with recurrent painless gastrointestinal bleeding for two months and failure to pass flatus and defecate with nausea and vomiting for ten days. Digital rectal examination found bright red blood and soft nodular masses 3 cm above the anal verge. Computed tomography showed that part of the descending colon and rectosigmoid colon was thickened with phleboliths in the intestinal wall. Colonoscopy exhibited bluish and reddish multinodular submucosal masses and flat submucosal serpentine vessels. Endoscopic ultrasonography showed anechoic cystic spaces within intestinal wall. The lesions were initially thought to be isolated VMs involving part of the descending colon and rectosigmoid colon. Laparoscopic subtotal proctocolectomy, pull-through transection and coloanal anastomosis and ileostomy were performed. Histopathology revealed intact mucosa and dilated, thin-walled blood vessels in the submucosa, muscularis, and serosa involving the entire colorectum. The patient recovered with complete symptomatic relief during the 52-mo follow-up period. CONCLUSION: The diagnosis of isolated GIVMs is challenging. The information presented here is significant for the diagnosis and management of symptoms.

KTa0.65Nb0.35O3 and Fe-doped KTa0.65Nb0.35O3 crystals were grown by the top-seeded solution growth method (TSSG). Fe ion doping significantly improves the electro-optic properties of cubic KTN crystals. We describe their electro-optic modulation theory and experimental research. The electro-optic modulation waveform deduced by theoretical calculation is basically consistent with the waveform measured in the experiment. We observed the attenuation of light modulation under multiple voltage cycles. The modulation curve of the crystal is inconsistent when the crystal voltage is boosting and bucking. Under the same voltage condition, the higher the incident light power, the faster the modulation depth attenuation. In this experiment, the size of the KTN crystal chip is 6 mm &times, 5 mm &times, 2 mm. We obtain the effective electro-optic coefficient as s11 &minus, s12 = 1.34 &times, 10&minus, 15 m2/V2, the half-wave voltage near the Curie temperature is 39 V.

At present, the safety of agricultural products is increasingly serious [1]. In view of the current situation, based on RFID and related technologies, the traceability system of agricultural products was designed and implemented. After defining the overall framework of the system, the various parts of the system were designed in detail. The selection of the types of information to be collected and the design of the database under the traceability environment were discussed. Based on the designed system model, the system was implemented. The traceability system consists of a collection subsystem, a query subsystem, and a storage subsystem. The system integrates long-distance information transmission and storage and RFID tag data storage. It stores, traces and analyzes information on agricultural products such as picking, transportation, warehousing and retailing. It is reliable, practical, low cost and easy to deploy.

During induction voltage test, the changes of data such as output voltage and output current reflects the changes of the equivalent parameters of the transformer. Through the analysis of testing data, diagnosis of winding deformation of the transformer can be made. Transformer condition evaluation can be provided on the basis of these data. In this paper, induction voltage test data is analyzed after a transformer tripping. Winding deformation of the transformer is judged. Relevance judgment is confirmed by disassembling inspection.

PURPOSE To find the lowest effective dose of verteporfin in the treatment of acute central serous chorioretinopathy with photodynamic therapy (PDT). METHODS Patients with acute central serous chorioretinopathy were chosen and treated with PDT with verteporfin. Decreasing doses of verteporfin were applied to the first 7 patients at 70%, 60%, 50%, 40%, 30%, 20%, and 10% of the full dose (6 mg/m). Other patients were treated with the effective lowest dose (30% of full dose). Fluorescein angiography, indocyanine green angiography, and optical coherence tomography recordings were performed before PDT and at 1 week, 2 weeks, 1 month, 3 months, 6 months, 9 months, and 12 months after PDT. The pretreatment and posttreatment best-corrected visual acuity were compared. RESULTS Fifteen eyes of 15 patients with the diagnosis of acute central serous chorioretinopathy were chosen and treated with PDT. The results at each dose suggested that 30% of the full dose of verteporfin was the lowest effective dose. The mean improvement in visual acuity was 4.1 +/- 0.25 lines at follow-up (mean 11.8 months). No complications were found during observation, except 1 patient at 70% dose who developed retinal angiomatous proliferation at the 1-month follow-up. CONCLUSION On the basis of the results of this study and available information regarding the expected rate of spontaneous resolution, 30% verteporfin dose seems to be safe and effective in the treatment of acute central serous chorioretinopathy.

Harmonic currents elimination are significant for improving efficiency and reliability for wind power system with PMSG. Several factors can induce harmonic current, in which the most significant is back EMF distortion. In order to compensate the voltage distortion, we propose a harmonic elimination method in multiple synchronous rotating reference frames in this paper. Different orders of current harmonics are transformed into their corresponding synchronous rotating frames respectively and PI regulators are used to compensate the voltage distortion, which are implemented in parallel with the fundamental regulator. Experiments are carried out to verify the effective of the proposed method, providing good voltage compensation results.