Empty Squares in Arbitrary Orientation Among Points

This paper studies empty squares in arbitrary orientation among a set $P$ of $n$ points in the plane. We prove that the number of empty squares with four contact pairs is between $\Omega(n)$ and $O(n^2)$, and that these bounds are tight, provided $P$ is in a certain general position. A contact pair of a square is a pair of a point $p\in P$ and a side $\ell$ of the square with $p\in \ell$. The upper bound $O(n^2)$ also applies to the number of empty squares with four contact points, while we construct a point set among which there is no square of four contact points. These combinatorial results are based on new observations on the $L_\infty$ Voronoi diagram with the axes rotated and its close connection to empty squares in arbitrary orientation. We then present an algorithm that maintains a combinatorial structure of the $L_\infty$ Voronoi diagram of $P$, while the axes of the plane continuously rotates by $90$ degrees, and simultaneously reports all empty squares with four contact pairs among $P$ in an output-sensitive way within $O(s\log n)$ time and $O(n)$ space, where $s$ denotes the number of reported squares. Several new algorithmic results are also obtained: a largest empty square among $P$ and a square annulus of minimum width or minimum area that encloses $P$ over all orientations can be computed in worst-case $O(n^2 \log n)$ time.Comment: 39 pages, 11 figure

Inscribing or Circumscribing a Histogon to a Convex Polygon

We consider two optimization problems of approximating a convex polygon, one by a largest inscribed histogon and the other by a smallest circumscribed histogon. An axis-aligned histogon is an axis-aligned rectilinear polygon such that every horizontal edge has an integer length. A histogon of orientation ? is a copy of an axis-aligned histogon rotated by ? in counterclockwise direction. The goal is to find a largest inscribed histogon and a smallest circumscribed histogon over all orientations in [0,?). Depending on whether the horizontal width of a histogon is predetermined or not, we consider several different versions of the problem and present exact algorithms. These optimization problems belong to shape analysis, classification, and simplification, and they have applications in various cost-optimization problems

Tap: A Novel Cellular Protein That Interacts with Tip of Herpesvirus Saimiri and Induces Lymphocyte Aggregation

AbstractTip of herpesvirus saimiri associates with Lck and down-regulates Lck-mediated activation. We identified a novel cellular Tip-associated protein (Tap) by a yeast two-hybrid screen. Tap associated with Tip following transient expression in COS-1 cells and stable expression in human Jurkat-T cells. Expression of Tip and Tap in Jurkat-T cells induced dramatic cell aggregation. Aggregation was likely caused by the up-regulated surface expression of adhesion molecules including integrin α, L-selectin, ICAM-3, and H-CAM. Furthermore, NF-κB transcriptional factor of aggregated cells had approximately 40-fold higher activity than that of parental cells. Thus, Tap is likely to be an important cellular mediator of Tip function in T cell transformation by herpesvirus saimiri

Long-term recurrence-free survival in a patient with stage IVB uterine carcinosarcoma

Uterine carcinosarcomas are rare and highly aggressive tumors with a poor prognosis. Due to early metastasis and disease progression, it is known to be far more aggressive than matched grade 3 endometroid endometrial carcinomas. Five-year survival for stage IV is reported to be 10% and overall survival for stage IVB is expected to be very poor. The authors report one case after experiencing long-term survival (over 5 years) for stage IVB carcinosarcoma of uterus. Total abdominal hysterectomy and bilateral salpingo-oophorectomy was performed to 56 year old patient for uterine myoma. On pathology report, uterine carcinosarcoma was diagnosed and image studies were performed. With the impression of stage IVB uterine carcinosarcoma, 6 cycles of chemotherapy (ifosfamide and cisplatin) was conducted as adjuvant. Up to recently (over 5 years), she maintains good performance scale without evidence of tumor recurrence or disease progression

Changes of empathy in medical college and medical school students: 1-year follow up study

BACKGROUND: This study aims to determine the correlation between medical education systems, medical college (MC) and medical school (MS), and empathy by investigating the changes in empathy among students with each additional year of medical education. METHODS: The subjects were MC and MS students who had participated in the same study the previous year. All participants completed the same self-report instruments: a questionnaire on sociodemographic characteristics, and the Korean edition of the Student Version of the Jefferson Scale of Empathy (JSE-S-K), Among 334 students, the final analysis was conducted on the data provided by 113 MC and 120 MS students, excluding 101 with incomplete data. RESULTS: The age and sex did not affect the changes in empathy. Though the JSE-S-K score of MS was significantly higher than that of MC in initial investigation, this study found no difference of empathy between MC and MS. CONCLUSION: Empathy increased significantly after one year of medical education. The difference between two education systems, MC and MS, did not affect the changes in empathy

Anticancer Effect of Nemopilema nomurai

Various kinds of animal venoms and their components have been widely studied for potential therapeutic applications. This study evaluated whether Nemopilema nomurai jellyfish venom (NnV) has anticancer activity. NnV strongly induced cytotoxicity of HepG2 cells through apoptotic cell death, as demonstrated by alterations of chromatic morphology, activation of procaspase-3, and an increase in the Bax/Bcl-2 ratio. Furthermore, NnV inhibited the phosphorylation of PI3K, PDK1, Akt, mTOR, p70S6K, and 4EBP1, whereas it enhanced the expression of p-PTEN. Interestingly, NnV also inactivated the negative feedback loops associated with Akt activation, as demonstrated by downregulation of Akt at Ser473 and mTOR at Ser2481. The anticancer effect of NnV was significant in a HepG2 xenograft mouse model, with no obvious toxicity. HepG2 cell death by NnV was inhibited by tetracycline, metalloprotease inhibitor, suggesting that metalloprotease component in NnV is closely related to the anticancer effects. This study demonstrates, for the first time, that NnV exerts highly selective cytotoxicity in HepG2 cells via dual inhibition of the Akt and mTOR signaling pathways, but not in normal cells

Benign Metastasizing Leiomyoma with Multiple Lymph Node Metastasis: A Case Report

This is a case report about benign metastasizing leiomyoma with multiple lymph node metastasis. A 34-year-old woman received an abdominal myomectomy for a suspicious leiomyoma. On the pathology report, atypical leiomyoma was suspected. Due to the suspicion of multiple lymph node metastasis on pelvis computed tomography (CT) 1 year after the operation, she was transferred to the Samsung Medical Center on October, 2009 for further work up. According to original slide review, it was determined to be a benign leiomyoma with a mitotic count <5/10 high-power fields, little cytological atypia and no tumor cell necrosis. Additional immunostaining was done. Multiple lymph node metastasis and a small lung nodule were identified on positron emission tomogarphy-CT and chest CT. Extensive debulking surgery and diagnostic video-assisted thoracoscopic surgery (VATS) wedge resection were subsequently done. Metastatic lesions were reported to have a histology similar to that of the original mass. VATS right upper lobectomy with mediastinal lymph node dissection was performed because of the pathology result of VATS (adenocarcinoma). She started taking an aromatase inhibitor (Letrozole®) and there was no evidence of recurrence of disease on an imaging study and no post-operative complications until recently

Psychometric Properties of the Hypomania Checklist-32 in Korean Patients with Mood Disorders

OBJECTIVE The aim of this study was to examine the validity of the Korean version of the Hypomania Checklist-32, second revision (HCL-32-R2) in mood disorder patients. METHODS A total of 454 patients who diagnosed as mood disorder according to Structured Clinical Interview for DSM-IV Axis I Disorders, clinician version (SCID-CV) (bipolar disorder [BD] I, n=190; BD-II, n=72; and major depressive disorder [MDD], n=192) completed the Korean module of the HCL-32-R2 (KHCL-32-R2). RESULTS The KHCL-32-R2 showed a three-factorial structure (eigenvalue ＞2) that accounted for 43.26% of the total variance. Factor 1 was labeled "active/elated" and included 16 items; factor 2, "irritable/distractible" and included 9 items; and factor 3 was labeled "risk-taking/indulging" and included 9 items. A score of 16 or more on the KHCL-32-R2 total scale score distinguished between BD and MDD, which yielded a sensitivity of 70% and a specificity of 70%. MDD and BD-II also could be differentiated at a cut-off of 15 with maximized sensitivity (0.67) and specificity (0.66). Cronbach's alpha of KHCL-32-R2 and its subsets (factors 1, 2, and 3) were 0.91, 0.89, 0.81 and 0.79, respectively. Correlations between KHCL-32-R2 and Montgomery- Asberg Depression Rating Scale, Young Mania Rating Scale and Korean version of Mood Disorder Questionnaire were -0.66 (p=0.41), -0.14 (p=0.9), and 0.61 (p＜0.001), respectively. CONCLUSION The KHCL-32-R2 may be a useful tool in distinguishing between bipolar and depressive patients in clinical settings

Current Situation and Issue of Industrial Accident Compensation Insurance

Industrial Accident Compensation Insurance (IACI) has a history of about 50 yr, and is the oldest social insurance system in Korea. After more than 20 times of revision improvements in benefits, its contents and claim systems have been upgraded. It became the protector of injured workers and their families, and at the same time became the system which could cope with both financial burden of employers and their responsibilities. However, there are some issues to be reformed to upgrade the IACI: 1) the problems in the approval system of occupational diseases, 2) quality improvement of workers' compensation medical care, 3) vocational rehabilitation and return to work, 4) workers' compensation premiums and out-of-pocket money of injured workers, 5) issues in application of IACI. Growth of IACI cannot be achieved by an effort of an individual. Efforts by workers, owners, and government, in addition to physicians and welfare professionals toward the same goal are required for the next level improvement of IACI