Development and validation of a prediction model for knee joint line orientation after high tibial osteotomy

Background Maintenance of optimal knee joint line orientation (KJLO) is important after high tibial osteotomy (HTO). No tools, however, are currently available that could predict the value of postoperative KJLO before surgery. First, this study sought to determine the effects of various preoperative anatomical alignment parameters to postoperative KJLO. Based upon these analyses, we aimed to devise an equation that predicts the value of postoperative KJLO. Methods A total of 14 radiographic parameters were measured in preoperative and postoperative full-limb standing anteroposterior radiographs on 50 patients who underwent open-wedge HTO. The parameters were analysed using multivariable linear regression to predict KJLO after HTO. External validation of the equation was done with 20 patients who underwent HTO at another institution. Results After HTO, KJLO increased from − 0.8° to 2.9° (P < 0.001). Based on the multivariable linear regression analysis, an equation was derived that can estimate postoperative KJLO after HTO; postoperative KJLO(°) = 1.029 + 0.560 × preoperative KJLO(°) + 0.310 × preoperative tibia plateau inclination(°) + 0.463 × aimed correction angle(°). The adjusted coefficients of determination value for this equation was 0.721. The equation also showed good calibration and predictability in external validation with predicted squared correlation coefficient of 0.867. Conclusions This study analysed the effects of preoperative anatomical alignment parameters on the postoperative KJLO. An equation which predicts postoperative KJLO with preoperative anatomical alignment factors was devised and validated. This equation would help in selecting optimal patients for HTO and in selecting the optimal target correction angle in HTO

A case of emphysematous hepatitis with spontaneous pneumoperitoneum in a patient with hilar cholangiocarcinoma

An 80-year-old woman with hilar cholangiocarcinoma was hospitalized due to sudden-onset abdominal pain. Computed tomography revealed hepatic necrosis accompanied with emphysematous change in the superior segment of the right liver (S7/S8), implying spontaneous rupture, based on the presence of perihepatic free air. Although urgent percutaneous drainage was performed, neither pus nor fluids were drained. These findings suggest emphysematous hepatitis with a hepatic mass. Despite the application of intensive care, the patient's condition deteriorated rapidly, and she died 3 days after admission to hospital. Liver gas has been reported in some clinical diseases (e.g., liver abscess) to be caused by gas-forming organisms; however, emphysematous hepatitis simulating emphysematous pyelonephritis is very rare. The case reported here was of fatal emphysematous hepatitis in a patient with hilar cholangiocarcinoma

A novel repeat sequence-based PCR (rep-PCR) using specific repeat sequences of Mycobacterium intracellulare as a DNA fingerprinting

Repetitive sequence-based PCR (rep-PCR) is a potential epidemiological technique that can provide high-throughput genotype fingerprints of heterogeneous Mycobacterium strains rapidly. Previously published rep-PCR primers, which are based on nucleotide sequences of Gram-negative bacteria may have low specificity for mycobacteria. Moreover, it was difficult to ensure the continuity of the study after the commercial rep-PCR kit was discontinued. Here, we designed a novel rep-PCR for Mycobacterium intracellulare, a major cause of nontuberculous mycobacterial pulmonary disease with frequent recurrence. We screened the 7,645 repeat sequences for 200 fragments from the genome of M. intracellulare ATCC 13950 in silico, finally generating five primers with more than 90% identity for a total of 226 loci in the genome. The five primers could make different band patterns depending on the genome of three different M. intracellulare strains using an in silico test. The novel rep-PCR with the five primers was conducted using 34 bacterial samples of 7 species containing 25 M. intracellulare clinical isolates, compared with previous published rep-PCRs. This shows distinguished patterns depending on species and blotting assay for 6 species implied the sequence specificity of the five primers. The Designed rep-PCR had a 95–98% of similarity value in the reproducibility test and showed 7 groups of fingerprints in M. intracellulare strains. Designed rep-PCR had a correlation value of 0.814 with VNTR, reference epidemiological method. This study provides a promising genotype fingerprinting method for tracing the recurrence of heterogeneous M. intracellulare

Managing power imbalance with cloud energy storage in imbalance band market environment

Imbalance band market is an alternative to traditional market structures which is proposed to ensure that system frequency remains within acceptable bounds. In an imbalance band market environment, the load-serving entities (LSEs) can purchase bands or reduce the load deviation by operating a battery energy storage system (BESS) to avoid the penalty for causing imbalance. The market concept would be effective in sharing balancing responsibility between a system operator (SO) and load-serving entities. In this study, the authors proposed a planning framework for a load serving entity (LSE) considering cloud energy storage (CES) business as a useful resource in the imbalance band market environment. The term of cloud energy storage is used as a platform that the operator owns and operates the storage, while subscribed clients pay a service fee for requesting charging and discharging operations. The simulation results show that operating cloud energy storage business is economically rational strategy for the LSE. The authors verified that a LSE operating the cloud energy storage business under an imbalance band market environment to pursue its own benefit better performs a part of the balance-maintaining obligation of the SO compared with a LSE not operating the cloud energy storage business.N

Business Feasibility Study for Storage-Based Customer Flexibility Platform of Load-Serving Entity

A storage-based customer flexibility (SCF) platform enables on-demand remote access to a shared pool of utility-scale energy storage resources at substantially low costs. It can provide users the ability to charge and discharge electrical energy to and from remote batteries. This study demonstrates the economic feasibility of an SCF platform business under realistic conditions. Accordingly, the load-serving entity is set as the SCF operator, and the subscriptions from various types of customers and multi-use battery energy storage systems are considered to increase profitability. An economic feasibility verification is provided based on the generating pattern of individual customers, and a robust optimization is performed for the SCF platform operations considering the market price uncertainty, aggregated requests, and customers&#x2019; willingness to pay for the SCF service. The proposed study is simulated in a California environment