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When black out occurs, the whole power grid is divided into several subsystems to increase the efficiency and shorten the duration of power system restoration by using parallel restoration strategy. Therefore, reasonable network partitioning in black start phase after large-scale power failures is important in both theory and practice. In this paper, a flexible black start network partitioning strategy considering the subsystem recovery time balance is proposed. Based on the rules of zone division and analyzing initial black start partitioning model of subsystem shortest recovery path, subsystem recovery time balance index is defined to represent disparity of every subsystem's restoration process. Meanwhile, a flexible factor of total recovery time is introduced as part of objective function with the time balance index, aiming at reducing waiting time of the synchronization operation and strengthens efficiency of black start at the cost of the least total time increment. The classic Dijkstra algorithm and improved genetic algorithm are employed to obtain the optimal restoration plan in the paper. Case study on IEEE 118-bus test system shows the validity of the methodology proposed. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The treatment of intramedullary infections after nailing usually includes removal of the nail, debridement, and, in some cases, insertion of antibiotic-impregnated cement beads. We use this self-made antibiotic cement rod to treat intramedullary infections. Compared with the beads, it provides some limited mechanical support and can be preserved in the canal for a long time. We reviewed 19 infected patients who underwent removal of the nails, excision of sinus tracks, debridement of the canal and insertion of the rods. No recurrent infection occurred in 18 cases and 11 cases achieved bone healing, 6 cases achieved partial union. One patient had nonunion and one patient underwent amputation because of severe primary trauma and long-term infection. The rod was removed between 35 and 123 days after implantation. We conclude that the antibiotic cement rods could be a relatively effective, simple and inexpensive method of treating intramedullary infections after nailing. [ABSTRACT FROM AUTHOR]

Past studies have shown that the cell surface lipopolysaccharides (LPSs) of the ubiquitous human gastric pathogen Helicobacter pylori (a type 1 carcinogen) isolated from people residing in Europe and North America express predominantly type 2 Lewis x (Lex) and Ley epitopes and, infrequently, type 1 Lea, Leb, and Led antigens. This production of Lewis blood-group structures by H. pylori LPSs, similar to those found in the surfaces of human gastric cells, allows the bacterium to mimic its human niche. In this study, LPSs of H.pylori strains extracted from patients living in China, Japan, and Singapore were chemically and serologically analyzed. When compared with Western H.pylori LPSs, these Asian strains showed a stronger tendency to produce type 1 blood groups. Of particular interest, and novel observations in H.pylori, the O-chain regions of strains F-58C and R-58A carried type 1 Lea without the presence of type 2 Lex, strains R-7A and H607 were shown to have the capability of producing the type 1 blood group A antigen, and strains CA2, H507, and H428 expressed simultaneously the difucosyl isomeric antigens, type 1 Leb and type 2 Ley. The apparent proclivity for the production of type 1 histo-blood group antigens in Asian H.pylori LPSs, as compared with Western strains, may be an adaptive evolutionary effect in that differences in the gastric cell surfaces of the respective hosts might be significantly dissimilar to select for the formation of different LPS structures on the resident H.pylori strain. [ABSTRACT FROM PUBLISHER]

Abstract: A new upconversion luminescence agent, 40CdF2·60BaF2·1.0Er2O3, was synthesized and its fluorescent spectrum was determined. This upconversion luminescence agent can emit five upconversion fluorescent peaks shown in the fluorescent spectrum whose wavelengths are all below 387nm under the excitation of 488nm visible light. This upconversion luminescence agent was mixed into nano rutile TiO2 powder by ultrasonic and boiling dispersion and then a novel doped nano TiO2 photocatalyst utilizing visible light was firstly prepared. The doped nano TiO2 powder was charactered by XRD and TEM and its photocatalytic activity was checked through the photocatalytic degradation reaction of azo fuchsine as a model compound under the visible light irradiation emitted by 6 three basic color lamps. Otherwise, in order to compare the photocatalytic activities the same experiment was carried out for undoped TiO2 powder. The degradation ratio of azo fuchsine in the presence of doped nano TiO2 powder reached 95% under visible light irradiation within 24h, which was obviously higher than the corresponding degradation ratio of 21% in the presence of undoped nano rutile TiO2 powder. It indicates that the upconversion luminescence agent prepared as dopant can effectively turn visible lights to ultraviolet lights that are absorbed by nano TiO2 particles to produce the electron–cavity pairs. All the results show that the nano rutile TiO2 powder doped with upconversion luminescence agent is a promising photocatalyst using sunlight for treating the industry dye wastewater in great force. [Copyright &y& Elsevier]

Objective: To explore the clinical outcomes of internal fixation or replacement for the treatment of radial head fractures through the extensor digitorum communis splitting approach., Methods: From July 2012 to May 2015, 25 patients with radial head fractures were reviewed. There were 17 males and 8 females, ranging in age from 20 to 67 years old, with a mean age of 39 years old. Twenty-one patients were treated with reconstruction of plate internal fixation, and 4 patients were treated with radial head replacement. According to Mason classification, 19 cases were type II and 6 cases were type III. All the patients underwent internal fixation or replacement through the extensor digitorum communis splitting approach. The patients were followed up clinically and radiographically until the beginning of fracture union and the entrance of function recovery of elbow motion into a plateau. The functional status of the elbow was evaluated using the Mayo Elbow Performance Index(MEPI). Radiographic signs of post-traumatic arthritis were rated according to the Broberg and Morrey system., Results: All the patients were followed up, and the average duration was 29 months (ranged, 12 to 56 months). The average range of flexion and extension was 120°, the extension was limited by 10°, and the flexion was 135°. The average forearm rotation range was 142°, pronation was 75°, supination was 67°. The mean MEPI was 93±7(ranged, 80 to 100 scores); according to the MEPI scoring criceria, 19 patients got an excellent functional result, 6 good. According to the Broberg and Morrey systems of traumatic arthritis, 19 patients were in grade 0, 6 in grade 1, and no patients in grade 2 or 3. No patients with nonunion of the radial head and failure of internal fixation were found. There were no complications of nerve or vascular injuries, and obvious limitation of elbow rotation. Heterotopic ossification around the elbow occurred in 4 cases, but the motion was not significantly limited. There were no complications such as prosthesis loosening and infection in 4 cases after radial head prosthesis replacement., Conclusions: The extensor digitorum communis splitting approach is an effective exposure method for internal fixation or replacement in the treatment of radial head fractures., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose.

To investigate role of delayed operation to stimulate growth of strong external callus in high-energy fractures, and explore a new way for bone healing. Twenty adult dogs were employed, and randomly divided into four groups, including group A-D. The dogs underwent osteotomy by wire saw in middle of femur, electric coagulation damaged surrounding periosteum, forming a 1 cm defect. Group A were internal fixed 14 days after osteotomy (higher-energy fractures delayed operation), Group B and C were internal fixed immediately (no delayed operation), Group D were internal fixed 14 days after osteotomy (delayed operation, but resected granulations around extremities). The results showed that groups of early fixed have no external callus growth and almost no growth in internal callus, these conditions leads to atrophy nonunion. On contrary, the porosis was strong and callus union was steady in group A and D, which have a delayed operation. In conclusion, early surgical fixation of high-energy fracture restrains external callus growth, easily lead to poor callus healing phenomenon of low-quality. Delayed surgical fixation can begin to repair soft tissues injury, stimulate external callus growth and improve fracture healing, so a small incision open reduction produce more robust growth effect than closed reduction.

Objective: To compare clinical results of treating Neer two- and three-part of proximal humeral fractures between anterolateral acromial approach and deltopectoral approach., Methods: From January 2009 to December 2012, 49 patients with Neer two- and three-part of proximal humeral fractures were treated with locked plate fixation. In anterolateral acromial approach group, there were 22 patients including 9 males and 13 females with an average of (63.2±7.6) years old, while 27 patients in deltopectoral approach including 12 males and 15 females with an average of (62.9±7.0) years old. Operative time, blood loss during operation, fracture healing time and complications were observed and compared, postoperative Constant-Murley scoring and VAS scoring were applied for evaluate function of shoulder joint and pain at 3 months, 1 and 2 years respectively., Results: All patients were followed up from 24 to 41 months with an average of 34.5 months. Operative time, blood loss, fracture healing time in anterolateral acromial approach group was (68.20±7.04) min, (151.30±20.57) ml, (10.88±4.90) weeks respectively, and better than that of in deltopectoral approach group which was (75.81±13.70) min, (242.10±37.25) ml and (13.60±2.45) weeks. Three months after operation, Constant-Murley scoring and VAS score in anterolateral acromial approach group was 88.32±5.45, 0.41±0.63 and better that of in deltopectoral approach group which was 63.53±8.31, 1.65±1.02. There was no significant differences between two groups in Constant-Murley scoring and VAS score at 1 and 2 years after operation. Each group has one case occurred loss of length humerus head height, and there was 1 case with subacromial impingement, 1 case with bolt loose and 2 cases with delayed union in deltopectoral approach. No axillary nerve injury, humeral head necrosis and breakage of internal fixation occurred both of two groups., Conclusion: Both of anterolateral acromial approach and deltopectoral approach are effective in treating Neer two- and three-part of proximal humeral fractures, and can obtain excellent outcomes. Moreover, anterolateral acromial approach has advantage of less trauma, less blood loss, shorter operative time, rapid recovery of shoulder joint function and fracture.

Objective: To research many clinical data of nonunion cases and discover the reasons for low capacity of bone growth., Methods: From October 1999 to April 2009,the source material of 280 nonunion cases were conducted and followed up. The data of the study included 230 males and 50 females,with an average age of 39.4 years old ranging from 19 to 62 years. The fracture position was femur in 129 cases,tibia in 83 cases,humerus in 47 cases, feet radius bone in 21 cases, the ratio was 46:29.6:16.8:7.5. The survey included primary injury process,damage degree and the effect of first treatment,hospital level of first treatment,timing of surgery for the first time, the early callus growth conditions and whether there were obvious technical errors., Results: There were 129 femoral nonunion cases with complete data,121 cases derived from closed fractures, 8 cases from open fractures; 111 cases was aseptic nonunion. 90% of femoral aseptic nonunion had no obvious callus growth, 80% of first treatment performed intraday surgical internal fixation, 10% were undergone operation within three days and 90% was early surgery totally., Conclusion: Low quality of bone callus growth is the main reason for current nonunion and the early surgical fixation has much to do with low quality of bone callus growth.