27 research outputs found
Conical Singular Solutions in (2+1)-Dimensional Gravity Employing the ADM Canonical Formalism
Topological solutions in the (2+1)-dimensional Einstein theory of gravity are
studied within the ADM canonical formalism. It is found that a conical
singularity appears in the closed de Sitter universe solution as a topological
defect in the case of the Einstein theory with a cosmological constant. Quantum
effects on the conical singularity are studied using the de Broglie-Bohm
interpretation. Finite quantum tunneling effects are obtained for the closed de
Sitter universe, while no quantum effects are obtained for an open universe.Comment: 15 pages, 3 figure
Dynamical mass generation of a two-component fermion in Maxwell-Chern-Simons QED_3: The lowest ladder approximation
Dynamical mass generation of a two-component fermion in with a
Chern-Simons term is investigated by solving the Schwinger-Dyson equation
formulated in the lowest ladder approximation. Dependence of the dynamical
fermion mass on a gauge-fixing parameter, a gauge coupling constant, and a
topological mass is examined by approximated analytical and also numerical
methods. The inclusion of the Chern-Simons term makes impossible to choose a
peculiar gauge in which a wave function renormalization is absent. The
numerical evaluation shows that the wave function renormalization is fairly
close to 1 in the Landau gauge. It means that this gauge is still a specific
gauge where the Ward-Takahashi identity is satisfied approximately. We also
find that the dynamical mass is almost constant if the topological mass is
larger than the coupling constant, while it decreases when the topological mass
is comparable to or smaller than the coupling constant and tends to the value
in without the Chern-Simons term.Comment: 22 pages, 9 figures, Version to appear in Phys. Rev.
Prenatally diagnosed giant umbilical cord resulted from patent urachus in a monochorionic diamniotic twin with selective intrauterine growth restriction
A long diffuse giant umbilical cord (GUC), caused by umbilical cord edema associated with a patent urachus, is an extremely rare anomaly. While patients with diffuse GUC appear to experience no significant complications and a good prognosis, little is known about their etiology and prenatal course. Here, we report the first case of prenatally diagnosed diffuse GUC resulted from patent urachus in a monochorionic diamniotic twin with selective intrauterine growth restriction. This case indicates that GUC is epigenetic and unrelated to multiple births
Holmium Laser Enucleation of the Prostate With Percutaneous Nephrostomy Into the Transplanted Kidney in Patient With Severe Benign Prostatic Hyperplasia With Vesicoureteral Reflux – A Case Report
A 66-year-old male, who had received renal transplantation 10Â years before, was admitted to our hospital with urinary retention. The prostate volume was 169.2Â ml. Furthermore, grade 5 vesicoureteral reflux (VUR) was shown in the cystography. Holmium laser enucleation of prostate (HoLEP) was performed, and percutaneous nephrostomy to the transplanted kidney was performed simultaneously to prevent from severe perioperative infection. After that, renal graft function improved and no urinary retention reoccurred, although surgical repair against VUR was necessary 10Â months after HoLEP. We conclude that surgical treatment for BPH after kidney transplantation should be strongly considered with care for infections
Remote Teaching Due to COVID-19: An Exploration of Its Effectiveness and Issues
Universities have quickly shifted to remote learning due to the COVID-19 pandemic. This study compared two versions—emergency remote teaching (ERT) and conventional face-to-face class (FFC)—of a course design based on the instructional design ARCS model for effectiveness and issues. The current study comprised 46 third-year nursing students who attended an FFC course in 2019, and 56 third-year students who took the ERT version in 2020. Students’ self-rated goal attainment and knowledge of genetics scores were compared before and after taking the courses. Scores between the two class types were compared using the Wilcoxon rank sum test. The students’ worksheets were evaluated using keyword frequency and content analyses. Both classes achieved their goals satisfactorily, and this study confirmed that for this course, ERT was as effective as FFC. A comparison of the increase in domain goal attainment scores per student showed that only the psychomotor domain item, “I can fully explain human diversity using genomic information”, was significantly different, as it was significantly higher for ERT (p = 0.003). This higher item in the ERT group suggests that ERT can pose a lack of practice caution in acquiring nursing skills
Prostatic Stromal Tumor of Uncertain Malignant Potential Which Was Difficult to Diagnose
Here, we report a case of stromal tumor of uncertain malignant potential (STUMP) that was difficult to diagnose. A 53-year-old male was found to have a hard nodule on digital rectal examination; magnetic resonance imaging revealed a large nodule on the left side of the prostate, indicating prostate cancer. However, pathological diagnosis of the biopsy specimen was benign prostatic hyperplasia. Although a papillary tumor in the prostatic urethra was also seen on urethrocystoscopy, the tumor specimen obtained from transurethral resection was not malignant. The tumor in the prostatic urethra recurred only 3 months after transurethral resection, and pathological findings revealed benign hyperplasia not only in the stromal tissue but also in the epithelium; therefore, the prostate tumor was suspected to be STUMP. It took many prostate pathologists a long time to reach the final diagnosis of STUMP. STUMP is a rare benign tumor, difficult to diagnose, and sometimes transforms into stromal sarcoma. Thus, we should consider radical resection in such cases